diff --git a/Makefile b/Makefile
index 25a7933b2fc..c85b1bca733 100644
--- a/Makefile
+++ b/Makefile
@@ -114,7 +114,7 @@ CC_msan = clang
 CXX_msan = clang++
 LD_msan = clang++
 LDXX_msan = clang++
-CPPFLAGS_msan = -O0 -fsanitize-coverage=edge -fsanitize=memory -fsanitize-memory-track-origins -fno-omit-frame-pointer -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1 -Wno-unused-command-line-argument -fPIE -pie -DGPR_NO_DIRECT_SYSCALLS
+CPPFLAGS_msan = -O0 -fsanitize-coverage=edge -fsanitize=memory -fsanitize-memory-track-origins -fsanitize-memory-use-after-dtor -fno-omit-frame-pointer -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1 -Wno-unused-command-line-argument -fPIE -pie -DGPR_NO_DIRECT_SYSCALLS
 LDFLAGS_msan = -fsanitize=memory -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1 -fPIE -pie $(if $(JENKINS_BUILD),-Wl$(comma)-Ttext-segment=0x7e0000000000,)
 DEFINES_msan = NDEBUG
 
diff --git a/README.md b/README.md
index 61479f34aa2..048614a2057 100644
--- a/README.md
+++ b/README.md
@@ -30,7 +30,6 @@ Libraries in different languages may be in different states of development. We a
 | Shared C [core library] | [src/core](src/core)                | 1.6     |
 | C++                     | [src/cpp](src/cpp)                  | 1.6     |
 | Ruby                    | [src/ruby](src/ruby)                | 1.6     |
-| NodeJS                  | [src/node](src/node)                | 1.6     |
 | Python                  | [src/python](src/python)            | 1.6     |
 | PHP                     | [src/php](src/php)                  | 1.6     |
 | C#                      | [src/csharp](src/csharp)            | 1.6     |
@@ -38,7 +37,8 @@ Libraries in different languages may be in different states of development. We a
 
 Java source code is in the [grpc-java](http://github.com/grpc/grpc-java)
 repository. Go source code is in the
-[grpc-go](http://github.com/grpc/grpc-go) repository.
+[grpc-go](http://github.com/grpc/grpc-go) repository. NodeJS source code is in the
+[grpc-node](https://github.com/grpc/grpc-node) repository.
 
 See [MANIFEST.md](MANIFEST.md) for a listing of top-level items in the
 repository.
diff --git a/WORKSPACE b/WORKSPACE
index 6df24e9c2ff..cead0bc877b 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -73,8 +73,8 @@ new_http_archive(
 
 http_archive(
     name = "com_google_protobuf",
-    strip_prefix = "protobuf-80a37e0782d2d702d52234b62dd4b9ec74fd2c95",
-    url = "https://github.com/google/protobuf/archive/80a37e0782d2d702d52234b62dd4b9ec74fd2c95.tar.gz",
+    strip_prefix = "protobuf-2761122b810fe8861004ae785cc3ab39f384d342",
+    url = "https://github.com/google/protobuf/archive/2761122b810fe8861004ae785cc3ab39f384d342.tar.gz",
 )
 
 new_http_archive(
diff --git a/build.yaml b/build.yaml
index 16e31eb588f..4f6194ecc41 100644
--- a/build.yaml
+++ b/build.yaml
@@ -4915,8 +4915,8 @@ configs:
   msan:
     CC: clang
     CPPFLAGS: -O0 -fsanitize-coverage=edge -fsanitize=memory -fsanitize-memory-track-origins
-      -fno-omit-frame-pointer -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1
-      -Wno-unused-command-line-argument -fPIE -pie -DGPR_NO_DIRECT_SYSCALLS
+      -fsanitize-memory-use-after-dtor -fno-omit-frame-pointer -DGTEST_HAS_TR1_TUPLE=0
+      -DGTEST_USE_OWN_TR1_TUPLE=1 -Wno-unused-command-line-argument -fPIE -pie -DGPR_NO_DIRECT_SYSCALLS
     CXX: clang++
     DEFINES: NDEBUG
     LD: clang++
@@ -4924,6 +4924,8 @@ configs:
       -fPIE -pie $(if $(JENKINS_BUILD),-Wl$(comma)-Ttext-segment=0x7e0000000000,)
     LDXX: clang++
     compile_the_world: true
+    test_environ:
+      MSAN_OPTIONS: poison_in_dtor=1
   mutrace:
     CPPFLAGS: -O3 -fno-omit-frame-pointer
     DEFINES: NDEBUG
diff --git a/examples/python/route_guide/route_guide_client.py b/examples/python/route_guide/route_guide_client.py
index 653f0d02c62..a0e32fb6f53 100644
--- a/examples/python/route_guide/route_guide_client.py
+++ b/examples/python/route_guide/route_guide_client.py
@@ -17,7 +17,6 @@
 from __future__ import print_function
 
 import random
-import time
 
 import grpc
 
@@ -66,7 +65,6 @@ def generate_route(feature_list):
     random_feature = feature_list[random.randint(0, len(feature_list) - 1)]
     print("Visiting point %s" % random_feature.location)
     yield random_feature.location
-    time.sleep(random.uniform(0.5, 1.5))
 
 
 def guide_record_route(stub):
@@ -91,7 +89,6 @@ def generate_messages():
   for msg in messages:
     print("Sending %s at %s" % (msg.message, msg.location))
     yield msg
-    time.sleep(random.uniform(0.5, 1.0))
 
 
 def guide_route_chat(stub):
diff --git a/requirements.txt b/requirements.txt
index 12969958aee..c976cef4cb8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,6 +3,6 @@ coverage>=4.0
 cython>=0.23
 enum34>=1.0.4
 futures>=2.2.0
-protobuf>=3.2.0
+protobuf>=3.5.0.post1
 six>=1.10
 wheel>=0.29
diff --git a/setup.py b/setup.py
index bf8aea6b6f2..bd07ccd73af 100644
--- a/setup.py
+++ b/setup.py
@@ -237,7 +237,7 @@ INSTALL_REQUIRES = (
     'six>=1.5.2',
     # TODO(atash): eventually split the grpcio package into a metapackage
     # depending on protobuf and the runtime component (independent of protobuf)
-    'protobuf>=3.3.0',
+    'protobuf>=3.5.0.post1',
 )
 
 if not PY3:
diff --git a/src/compiler/cpp_generator.cc b/src/compiler/cpp_generator.cc
index 3adf0fa451f..dec8cd0f25f 100644
--- a/src/compiler/cpp_generator.cc
+++ b/src/compiler/cpp_generator.cc
@@ -104,7 +104,7 @@ grpc::string GetHeaderPrologue(grpc_generator::File* file,
     grpc::string leading_comments = file->GetLeadingComments("//");
     if (!leading_comments.empty()) {
       printer->Print(vars, "// Original file comments:\n");
-      printer->Print(leading_comments.c_str());
+      printer->PrintRaw(leading_comments.c_str());
     }
     printer->Print(vars, "#ifndef GRPC_$filename_identifier$__INCLUDED\n");
     printer->Print(vars, "#define GRPC_$filename_identifier$__INCLUDED\n");
diff --git a/src/compiler/csharp_generator.cc b/src/compiler/csharp_generator.cc
index e0957bf9bb2..40fe0b054a5 100644
--- a/src/compiler/csharp_generator.cc
+++ b/src/compiler/csharp_generator.cc
@@ -666,7 +666,7 @@ grpc::string GetServices(const FileDescriptor* file, bool generate_client,
     grpc::string leading_comments = GetCsharpComments(file, true);
     if (!leading_comments.empty()) {
       out.Print("// Original file comments:\n");
-      out.Print(leading_comments.c_str());
+      out.PrintRaw(leading_comments.c_str());
     }
 
     out.Print("#pragma warning disable 1591\n");
diff --git a/src/compiler/node_generator.cc b/src/compiler/node_generator.cc
index ed835b44451..661587cbd63 100644
--- a/src/compiler/node_generator.cc
+++ b/src/compiler/node_generator.cc
@@ -250,7 +250,7 @@ grpc::string GenerateFile(const FileDescriptor* file) {
     grpc::string leading_comments = GetNodeComments(file, true);
     if (!leading_comments.empty()) {
       out.Print("// Original file comments:\n");
-      out.Print(leading_comments.c_str());
+      out.PrintRaw(leading_comments.c_str());
     }
 
     out.Print("'use strict';\n");
diff --git a/src/compiler/objective_c_generator.cc b/src/compiler/objective_c_generator.cc
index 349f1dc2818..8fe30e97e94 100644
--- a/src/compiler/objective_c_generator.cc
+++ b/src/compiler/objective_c_generator.cc
@@ -65,7 +65,7 @@ static void PrintAllComments(const DescriptorType* desc, Printer* printer) {
     printer->Print(" * ");
     size_t start_pos = it->find_first_not_of(' ');
     if (start_pos != grpc::string::npos) {
-      printer->Print(it->c_str() + start_pos);
+      printer->PrintRaw(it->c_str() + start_pos);
     }
     printer->Print("\n");
   }
diff --git a/src/compiler/objective_c_plugin.cc b/src/compiler/objective_c_plugin.cc
index 53ff81f94a4..d5d488e84d4 100644
--- a/src/compiler/objective_c_plugin.cc
+++ b/src/compiler/objective_c_plugin.cc
@@ -51,12 +51,15 @@ class ObjectiveCGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
     {
       // Generate .pbrpc.h
 
-      ::grpc::string imports = ::grpc::string("#import \"") + file_name +
-                               ".pbobjc.h\"\n\n"
-                               "#import <ProtoRPC/ProtoService.h>\n"
-                               "#import <ProtoRPC/ProtoRPC.h>\n"
-                               "#import <RxLibrary/GRXWriteable.h>\n"
-                               "#import <RxLibrary/GRXWriter.h>\n";
+      ::grpc::string imports =
+          ::grpc::string("#if !GPB_GRPC_FORWARD_DECLARE_MESSAGE_PROTO\n") +
+          "#import \"" + file_name +
+          ".pbobjc.h\"\n"
+          "#endif\n\n"
+          "#import <ProtoRPC/ProtoService.h>\n"
+          "#import <ProtoRPC/ProtoRPC.h>\n"
+          "#import <RxLibrary/GRXWriteable.h>\n"
+          "#import <RxLibrary/GRXWriter.h>\n";
 
       ::grpc::string proto_imports;
       proto_imports += "#if GPB_GRPC_FORWARD_DECLARE_MESSAGE_PROTO\n" +
@@ -105,7 +108,10 @@ class ObjectiveCGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
       // Generate .pbrpc.m
 
       ::grpc::string imports = ::grpc::string("#import \"") + file_name +
-                               ".pbrpc.h\"\n\n"
+                               ".pbrpc.h\"\n"
+                               "#import \"" +
+                               file_name +
+                               ".pbobjc.h\"\n\n"
                                "#import <ProtoRPC/ProtoRPC.h>\n"
                                "#import <RxLibrary/GRXWriter+Immediate.h>\n";
       for (int i = 0; i < file->dependency_count(); i++) {
diff --git a/src/compiler/php_generator.cc b/src/compiler/php_generator.cc
index 1ff9520d7f5..d9705e80778 100644
--- a/src/compiler/php_generator.cc
+++ b/src/compiler/php_generator.cc
@@ -164,7 +164,7 @@ grpc::string GenerateFile(const FileDescriptor* file,
     grpc::string leading_comments = GetPHPComments(file, "//");
     if (!leading_comments.empty()) {
       out.Print("// Original file comments:\n");
-      out.Print(leading_comments.c_str());
+      out.PrintRaw(leading_comments.c_str());
     }
 
     map<grpc::string, grpc::string> vars;
diff --git a/src/compiler/protobuf_plugin.h b/src/compiler/protobuf_plugin.h
index 1551908156a..b971af13109 100644
--- a/src/compiler/protobuf_plugin.h
+++ b/src/compiler/protobuf_plugin.h
@@ -141,6 +141,7 @@ class ProtoBufPrinter : public grpc_generator::Printer {
   }
 
   void Print(const char* string) { printer_.Print(string); }
+  void PrintRaw(const char* string) { printer_.PrintRaw(string); }
   void Indent() { printer_.Indent(); }
   void Outdent() { printer_.Outdent(); }
 
diff --git a/src/compiler/python_generator.cc b/src/compiler/python_generator.cc
index c1ae7d31adf..8a0b8894549 100644
--- a/src/compiler/python_generator.cc
+++ b/src/compiler/python_generator.cc
@@ -101,7 +101,7 @@ void PrivateGenerator::PrintAllComments(StringVector comments,
        ++it) {
     size_t start_pos = it->find_first_not_of(' ');
     if (start_pos != grpc::string::npos) {
-      out->Print(it->c_str() + start_pos);
+      out->PrintRaw(it->c_str() + start_pos);
     }
     out->Print("\n");
   }
diff --git a/src/compiler/ruby_generator.cc b/src/compiler/ruby_generator.cc
index ed7e074b470..e81dea603ba 100644
--- a/src/compiler/ruby_generator.cc
+++ b/src/compiler/ruby_generator.cc
@@ -174,7 +174,7 @@ grpc::string GetServices(const FileDescriptor* file) {
     grpc::string leading_comments = GetRubyComments(file, true);
     if (!leading_comments.empty()) {
       out.Print("# Original file comments:\n");
-      out.Print(leading_comments.c_str());
+      out.PrintRaw(leading_comments.c_str());
     }
 
     out.Print("\n");
diff --git a/src/compiler/schema_interface.h b/src/compiler/schema_interface.h
index b2021f29267..c000478e681 100644
--- a/src/compiler/schema_interface.h
+++ b/src/compiler/schema_interface.h
@@ -86,6 +86,7 @@ struct Printer {
   virtual void Print(const std::map<grpc::string, grpc::string>& vars,
                      const char* template_string) = 0;
   virtual void Print(const char* string) = 0;
+  virtual void PrintRaw(const char* string) = 0;
   virtual void Indent() = 0;
   virtual void Outdent() = 0;
 };
diff --git a/src/core/lib/iomgr/sockaddr_utils.cc b/src/core/lib/iomgr/sockaddr_utils.cc
index 3477fb52cd9..0c0a2fe5b2e 100644
--- a/src/core/lib/iomgr/sockaddr_utils.cc
+++ b/src/core/lib/iomgr/sockaddr_utils.cc
@@ -148,7 +148,7 @@ int grpc_sockaddr_to_string(char** out,
   grpc_resolved_address addr_normalized;
   char ntop_buf[INET6_ADDRSTRLEN];
   const void* ip = nullptr;
-  int port;
+  int port = 0;
   uint32_t sin6_scope_id = 0;
   int ret;
 
diff --git a/src/objective-c/tests/CoreCronetEnd2EndTests/CoreCronetEnd2EndTests.m b/src/objective-c/tests/CoreCronetEnd2EndTests/CoreCronetEnd2EndTests.mm
similarity index 75%
rename from src/objective-c/tests/CoreCronetEnd2EndTests/CoreCronetEnd2EndTests.m
rename to src/objective-c/tests/CoreCronetEnd2EndTests/CoreCronetEnd2EndTests.mm
index 453b0752c31..d5e668a858a 100644
--- a/src/objective-c/tests/CoreCronetEnd2EndTests/CoreCronetEnd2EndTests.m
+++ b/src/objective-c/tests/CoreCronetEnd2EndTests/CoreCronetEnd2EndTests.mm
@@ -58,7 +58,7 @@ static grpc_end2end_test_fixture chttp2_create_fixture_secure_fullstack(
   grpc_end2end_test_fixture f;
   int port = grpc_pick_unused_port_or_die();
   fullstack_secure_fixture_data *ffd =
-      gpr_malloc(sizeof(fullstack_secure_fixture_data));
+      (fullstack_secure_fixture_data*)gpr_malloc(sizeof(fullstack_secure_fixture_data));
   memset(&f, 0, sizeof(f));
 
   gpr_join_host_port(&ffd->localaddr, "127.0.0.1", port);
@@ -81,7 +81,7 @@ static void process_auth_failure(void *state, grpc_auth_context *ctx,
 static void cronet_init_client_secure_fullstack(grpc_end2end_test_fixture *f,
                                                 grpc_channel_args *client_args,
                                                 stream_engine *cronetEngine) {
-  fullstack_secure_fixture_data *ffd = f->fixture_data;
+  fullstack_secure_fixture_data *ffd = (fullstack_secure_fixture_data *)f->fixture_data;
   f->client = grpc_cronet_secure_channel_create(cronetEngine, ffd->localaddr,
                                                 client_args, NULL);
   GPR_ASSERT(f->client != NULL);
@@ -90,7 +90,7 @@ static void cronet_init_client_secure_fullstack(grpc_end2end_test_fixture *f,
 static void chttp2_init_server_secure_fullstack(
     grpc_end2end_test_fixture *f, grpc_channel_args *server_args,
     grpc_server_credentials *server_creds) {
-  fullstack_secure_fixture_data *ffd = f->fixture_data;
+  fullstack_secure_fixture_data *ffd = (fullstack_secure_fixture_data *)f->fixture_data;
   if (f->server) {
     grpc_server_destroy(f->server);
   }
@@ -103,7 +103,7 @@ static void chttp2_init_server_secure_fullstack(
 }
 
 static void chttp2_tear_down_secure_fullstack(grpc_end2end_test_fixture *f) {
-  fullstack_secure_fixture_data *ffd = f->fixture_data;
+  fullstack_secure_fixture_data *ffd = (fullstack_secure_fixture_data *)f->fixture_data;
   gpr_free(ffd->localaddr);
   gpr_free(ffd);
 }
@@ -171,7 +171,7 @@ static char *roots_filename;
   FILE *roots_file;
   size_t roots_size = strlen(test_root_cert);
 
-  char *argv[] = {"CoreCronetEnd2EndTests"};
+  char *argv[] = {(char *)"CoreCronetEnd2EndTests"};
   grpc_test_init(1, argv);
   grpc_end2end_tests_pre_init();
 
@@ -207,7 +207,7 @@ static char *roots_filename;
 }
 
 - (void)testIndividualCase:(char *)test_case {
-  char *argv[] = {"h2_ssl", test_case};
+  char *argv[] = {(char *)"h2_ssl", test_case};
 
   for (int i = 0; i < sizeof(configs) / sizeof(*configs); i++) {
     grpc_end2end_tests(sizeof(argv) / sizeof(argv[0]), argv, configs[i]);
@@ -217,182 +217,182 @@ static char *roots_filename;
 // TODO(mxyan): Use NSStringFromSelector(_cmd) to acquire test name from the
 // test case method name, so that bodies of test cases can stay identical
 - (void)testAuthorityNotSupported {
-  [self testIndividualCase:"authority_not_supported"];
+  [self testIndividualCase:(char *)"authority_not_supported"];
 }
 
 - (void)testBadHostname {
-  [self testIndividualCase:"bad_hostname"];
+  [self testIndividualCase:(char *)"bad_hostname"];
 }
 
 - (void)testBinaryMetadata {
   // NOT SUPPORTED
-  //[self testIndividualCase:"binary_metadata"];
+  //[self testIndividualCase:(char *)"binary_metadata"];
 }
 
 - (void)testCallCreds {
   // NOT SUPPORTED
-  // [self testIndividualCase:"call_creds"];
+  // [self testIndividualCase:(char *)"call_creds"];
 }
 
 - (void)testCancelAfterAccept {
-  [self testIndividualCase:"cancel_after_accept"];
+  [self testIndividualCase:(char *)"cancel_after_accept"];
 }
 
 - (void)testCancelAfterClientDone {
-  [self testIndividualCase:"cancel_after_client_done"];
+  [self testIndividualCase:(char *)"cancel_after_client_done"];
 }
 
 - (void)testCancelAfterInvoke {
-  [self testIndividualCase:"cancel_after_invoke"];
+  [self testIndividualCase:(char *)"cancel_after_invoke"];
 }
 
 - (void)testCancelAfterRoundTrip {
-  [self testIndividualCase:"cancel_after_round_trip"];
+  [self testIndividualCase:(char *)"cancel_after_round_trip"];
 }
 
 - (void)testCancelBeforeInvoke {
-  [self testIndividualCase:"cancel_before_invoke"];
+  [self testIndividualCase:(char *)"cancel_before_invoke"];
 }
 
 - (void)testCancelInAVacuum {
-  [self testIndividualCase:"cancel_in_a_vacuum"];
+  [self testIndividualCase:(char *)"cancel_in_a_vacuum"];
 }
 
 - (void)testCancelWithStatus {
-  [self testIndividualCase:"cancel_with_status"];
+  [self testIndividualCase:(char *)"cancel_with_status"];
 }
 
 - (void)testCompressedPayload {
-  [self testIndividualCase:"compressed_payload"];
+  [self testIndividualCase:(char *)"compressed_payload"];
 }
 
 - (void)testConnectivity {
   // NOT SUPPORTED
-  // [self testIndividualCase:"connectivity"];
+  // [self testIndividualCase:(char *)"connectivity"];
 }
 
 - (void)testDefaultHost {
-  [self testIndividualCase:"default_host"];
+  [self testIndividualCase:(char *)"default_host"];
 }
 
 - (void)testDisappearingServer {
-  [self testIndividualCase:"disappearing_server"];
+  [self testIndividualCase:(char *)"disappearing_server"];
 }
 
 - (void)testEmptyBatch {
-  [self testIndividualCase:"empty_batch"];
+  [self testIndividualCase:(char *)"empty_batch"];
 }
 
 - (void)testFilterCausesClose {
   // NOT SUPPORTED
-  // [self testIndividualCase:"filter_causes_close"];
+  // [self testIndividualCase:(char *)"filter_causes_close"];
 }
 
 - (void)testGracefulServerShutdown {
-  [self testIndividualCase:"graceful_server_shutdown"];
+  [self testIndividualCase:(char *)"graceful_server_shutdown"];
 }
 
 - (void)testHighInitialSeqno {
-  [self testIndividualCase:"high_initial_seqno"];
+  [self testIndividualCase:(char *)"high_initial_seqno"];
 }
 
 - (void)testHpackSize {
   // NOT SUPPORTED
-  // [self testIndividualCase:"hpack_size"];
+  // [self testIndividualCase:(char *)"hpack_size"];
 }
 
 - (void)testIdempotentRequest {
   // NOT SUPPORTED
-  // [self testIndividualCase:"idempotent_request"];
+  // [self testIndividualCase:(char *)"idempotent_request"];
 }
 
 - (void)testInvokeLargeRequest {
   // NOT SUPPORTED (frame size)
-  // [self testIndividualCase:"invoke_large_request"];
+  // [self testIndividualCase:(char *)"invoke_large_request"];
 }
 
 - (void)testLargeMetadata {
   // NOT SUPPORTED
-  // [self testIndividualCase:"large_metadata"];
+  // [self testIndividualCase:(char *)"large_metadata"];
 }
 
 - (void)testMaxConcurrentStreams {
-  [self testIndividualCase:"max_concurrent_streams"];
+  [self testIndividualCase:(char *)"max_concurrent_streams"];
 }
 
 - (void)testMaxMessageLength {
   // NOT SUPPORTED (close_error)
-  // [self testIndividualCase:"max_message_length"];
+  // [self testIndividualCase:(char *)"max_message_length"];
 }
 
 - (void)testNegativeDeadline {
-  [self testIndividualCase:"negative_deadline"];
+  [self testIndividualCase:(char *)"negative_deadline"];
 }
 
 - (void)testNetworkStatusChange {
-  [self testIndividualCase:"network_status_change"];
+  [self testIndividualCase:(char *)"network_status_change"];
 }
 
 - (void)testNoOp {
-  [self testIndividualCase:"no_op"];
+  [self testIndividualCase:(char *)"no_op"];
 }
 
 - (void)testPayload {
-  [self testIndividualCase:"payload"];
+  [self testIndividualCase:(char *)"payload"];
 }
 
 - (void)testPing {
   // NOT SUPPORTED
-  // [self testIndividualCase:"ping"];
+  // [self testIndividualCase:(char *)"ping"];
 }
 
 - (void)testPingPongStreaming {
-  [self testIndividualCase:"ping_pong_streaming"];
+  [self testIndividualCase:(char *)"ping_pong_streaming"];
 }
 
 - (void)testRegisteredCall {
-  [self testIndividualCase:"registered_call"];
+  [self testIndividualCase:(char *)"registered_call"];
 }
 
 - (void)testRequestWithFlags {
   // NOT SUPPORTED
-  // [self testIndividualCase:"request_with_flags"];
+  // [self testIndividualCase:(char *)"request_with_flags"];
 }
 
 - (void)testRequestWithPayload {
-  [self testIndividualCase:"request_with_payload"];
+  [self testIndividualCase:(char *)"request_with_payload"];
 }
 
 - (void)testServerFinishesRequest {
-  [self testIndividualCase:"server_finishes_request"];
+  [self testIndividualCase:(char *)"server_finishes_request"];
 }
 
 - (void)testShutdownFinishesCalls {
-  [self testIndividualCase:"shutdown_finishes_calls"];
+  [self testIndividualCase:(char *)"shutdown_finishes_calls"];
 }
 
 - (void)testShutdownFinishesTags {
-  [self testIndividualCase:"shutdown_finishes_tags"];
+  [self testIndividualCase:(char *)"shutdown_finishes_tags"];
 }
 
 - (void)testSimpleDelayedRequest {
-  [self testIndividualCase:"simple_delayed_request"];
+  [self testIndividualCase:(char *)"simple_delayed_request"];
 }
 
 - (void)testSimpleMetadata {
-  [self testIndividualCase:"simple_metadata"];
+  [self testIndividualCase:(char *)"simple_metadata"];
 }
 
 - (void)testSimpleRequest {
-  [self testIndividualCase:"simple_request"];
+  [self testIndividualCase:(char *)"simple_request"];
 }
 
 - (void)testStreamingErrorResponse {
-  [self testIndividualCase:"streaming_error_response"];
+  [self testIndividualCase:(char *)"streaming_error_response"];
 }
 
 - (void)testTrailingMetadata {
-  [self testIndividualCase:"trailing_metadata"];
+  [self testIndividualCase:(char *)"trailing_metadata"];
 }
 
 @end
diff --git a/src/objective-c/tests/Tests.xcodeproj/project.pbxproj b/src/objective-c/tests/Tests.xcodeproj/project.pbxproj
index 2f0c8cfe18e..52631b4dce9 100644
--- a/src/objective-c/tests/Tests.xcodeproj/project.pbxproj
+++ b/src/objective-c/tests/Tests.xcodeproj/project.pbxproj
@@ -14,7 +14,7 @@
 		20DFDF829DD993A4A00D5662 /* libPods-RxLibraryUnitTests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = A58BE6DF1C62D1739EBB2C78 /* libPods-RxLibraryUnitTests.a */; };
 		333E8FC01C8285B7C547D799 /* libPods-InteropTestsLocalCleartext.a in Frameworks */ = {isa = PBXBuildFile; fileRef = FD346DB2C23F676C4842F3FF /* libPods-InteropTestsLocalCleartext.a */; };
 		3D7C85F6AA68C4A205E3BA16 /* libPods-Tests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 20DFF2F3C97EF098FE5A3171 /* libPods-Tests.a */; };
-		5E8A5DA71D3840B4000F8BC4 /* CoreCronetEnd2EndTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 5E8A5DA61D3840B4000F8BC4 /* CoreCronetEnd2EndTests.m */; };
+		5E8A5DA71D3840B4000F8BC4 /* CoreCronetEnd2EndTests.mm in Sources */ = {isa = PBXBuildFile; fileRef = 5E8A5DA61D3840B4000F8BC4 /* CoreCronetEnd2EndTests.mm */; };
 		5E8A5DA91D3840B4000F8BC4 /* libTests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 635697C71B14FC11007A7283 /* libTests.a */; };
 		5EAD6D271E27047400002378 /* CronetUnitTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 5EAD6D261E27047400002378 /* CronetUnitTests.m */; };
 		5EAD6D291E27047400002378 /* libTests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 635697C71B14FC11007A7283 /* libTests.a */; };
@@ -140,7 +140,7 @@
 		573450F334B331D0BED8B961 /* Pods-CoreCronetEnd2EndTests.cronet.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-CoreCronetEnd2EndTests.cronet.xcconfig"; path = "Pods/Target Support Files/Pods-CoreCronetEnd2EndTests/Pods-CoreCronetEnd2EndTests.cronet.xcconfig"; sourceTree = "<group>"; };
 		5761E98978DDDF136A58CB7E /* Pods-AllTests.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-AllTests.release.xcconfig"; path = "Pods/Target Support Files/Pods-AllTests/Pods-AllTests.release.xcconfig"; sourceTree = "<group>"; };
 		5E8A5DA41D3840B4000F8BC4 /* CoreCronetEnd2EndTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = CoreCronetEnd2EndTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
-		5E8A5DA61D3840B4000F8BC4 /* CoreCronetEnd2EndTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = CoreCronetEnd2EndTests.m; sourceTree = "<group>"; };
+		5E8A5DA61D3840B4000F8BC4 /* CoreCronetEnd2EndTests.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = CoreCronetEnd2EndTests.mm; sourceTree = "<group>"; };
 		5EAD6D241E27047400002378 /* CronetUnitTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = CronetUnitTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		5EAD6D261E27047400002378 /* CronetUnitTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = CronetUnitTests.m; sourceTree = "<group>"; };
 		5EAD6D281E27047400002378 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
@@ -343,7 +343,7 @@
 		5E8A5DA51D3840B4000F8BC4 /* CoreCronetEnd2EndTests */ = {
 			isa = PBXGroup;
 			children = (
-				5E8A5DA61D3840B4000F8BC4 /* CoreCronetEnd2EndTests.m */,
+				5E8A5DA61D3840B4000F8BC4 /* CoreCronetEnd2EndTests.mm */,
 			);
 			path = CoreCronetEnd2EndTests;
 			sourceTree = "<group>";
@@ -1196,7 +1196,7 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				5E8A5DA71D3840B4000F8BC4 /* CoreCronetEnd2EndTests.m in Sources */,
+				5E8A5DA71D3840B4000F8BC4 /* CoreCronetEnd2EndTests.mm in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
diff --git a/src/python/grpcio/grpc/__init__.py b/src/python/grpcio/grpc/__init__.py
index 70558a699a2..558ce42129b 100644
--- a/src/python/grpcio/grpc/__init__.py
+++ b/src/python/grpcio/grpc/__init__.py
@@ -424,17 +424,19 @@ class ServerCredentials(object):
         self._credentials = credentials
 
 
-class ServerCertificateConfig(object):
-    """A certificate config for use with an SSL-enabled Server, e.g., can
-    be returned in the certificate config fetching callback.
+class ServerCertificateConfiguration(object):
+    """A certificate configuration for use with an SSL-enabled Server.
+
+    Instances of this class can be returned in the certificate configuration
+    fetching callback.
 
     This class has no supported interface -- it exists to define the
     type of its instances and its instances exist to be passed to
     other functions.
     """
 
-    def __init__(self, cert_config):
-        self._cert_config = cert_config
+    def __init__(self, certificate_configuration):
+        self._certificate_configuration = certificate_configuration
 
 
 ########################  Multi-Callable Interfaces  ###########################
@@ -1265,9 +1267,9 @@ def ssl_server_credentials(private_key_certificate_chain_pairs,
             ], require_client_auth))
 
 
-def ssl_server_certificate_config(private_key_certificate_chain_pairs,
-                                  root_certificates=None):
-    """Creates a ServerCertificateConfig for use with an SSL-enabled Server.
+def ssl_server_certificate_configuration(private_key_certificate_chain_pairs,
+                                         root_certificates=None):
+    """Creates a ServerCertificateConfiguration for use with a Server.
 
     Args:
       private_key_certificate_chain_pairs: A collection of pairs of
@@ -1277,38 +1279,38 @@ def ssl_server_certificate_config(private_key_certificate_chain_pairs,
         certificates that the server will use to verify client authentication.
 
     Returns:
-      A ServerCertificateConfig that can be returned in the certificate config
-      fetching callback.
+      A ServerCertificateConfiguration that can be returned in the certificate
+        configuration fetching callback.
     """
     if len(private_key_certificate_chain_pairs) == 0:
         raise ValueError(
             'At least one private key-certificate chain pair is required!')
     else:
-        return ServerCertificateConfig(
+        return ServerCertificateConfiguration(
             _cygrpc.server_certificate_config_ssl(root_certificates, [
                 _cygrpc.SslPemKeyCertPair(key, pem)
                 for key, pem in private_key_certificate_chain_pairs
             ]))
 
 
-def ssl_server_credentials_dynamic_cert_config(initial_cert_config,
-                                               cert_config_fetcher,
-                                               require_client_auth=False):
+def dynamic_ssl_server_credentials(initial_certificate_configuration,
+                                   certificate_configuration_fetcher,
+                                   require_client_authentication=False):
     """Creates a ServerCredentials for use with an SSL-enabled Server.
 
     Args:
-      initial_cert_config (ServerCertificateConfig): the certificate
-        config with which the server will be initialized.
-      cert_config_fetcher (callable): a callable that takes no
-        arguments and should return a ServerCertificateConfig to
-        replace the server's current cert, or None for no change
+      initial_certificate_configuration (ServerCertificateConfiguration): The
+        certificate configuration with which the server will be initialized.
+      certificate_configuration_fetcher (callable): A callable that takes no
+        arguments and should return a ServerCertificateConfiguration to
+        replace the server's current certificate, or None for no change
         (i.e., the server will continue its current certificate
         config). The library will call this callback on *every* new
         client connection before starting the TLS handshake with the
         client, thus allowing the user application to optionally
-        return a new ServerCertificateConfig that the server will then
+        return a new ServerCertificateConfiguration that the server will then
         use for the handshake.
-      require_client_auth: A boolean indicating whether or not to
+      require_client_authentication: A boolean indicating whether or not to
         require clients to be authenticated.
 
     Returns:
@@ -1316,7 +1318,8 @@ def ssl_server_credentials_dynamic_cert_config(initial_cert_config,
     """
     return ServerCredentials(
         _cygrpc.server_credentials_ssl_dynamic_cert_config(
-            initial_cert_config, cert_config_fetcher, require_client_auth))
+            initial_certificate_configuration,
+            certificate_configuration_fetcher, require_client_authentication))
 
 
 def channel_ready_future(channel):
@@ -1401,19 +1404,19 @@ __all__ = ('FutureTimeoutError', 'FutureCancelledError', 'Future',
            'ChannelConnectivity', 'StatusCode', 'RpcError', 'RpcContext',
            'Call', 'ChannelCredentials', 'CallCredentials',
            'AuthMetadataContext', 'AuthMetadataPluginCallback',
-           'AuthMetadataPlugin', 'ServerCertificateConfig', 'ServerCredentials',
-           'UnaryUnaryMultiCallable', 'UnaryStreamMultiCallable',
-           'StreamUnaryMultiCallable', 'StreamStreamMultiCallable', 'Channel',
-           'ServicerContext', 'RpcMethodHandler', 'HandlerCallDetails',
-           'GenericRpcHandler', 'ServiceRpcHandler', 'Server',
-           'unary_unary_rpc_method_handler', 'unary_stream_rpc_method_handler',
-           'stream_unary_rpc_method_handler',
+           'AuthMetadataPlugin', 'ServerCertificateConfiguration',
+           'ServerCredentials', 'UnaryUnaryMultiCallable',
+           'UnaryStreamMultiCallable', 'StreamUnaryMultiCallable',
+           'StreamStreamMultiCallable', 'Channel', 'ServicerContext',
+           'RpcMethodHandler', 'HandlerCallDetails', 'GenericRpcHandler',
+           'ServiceRpcHandler', 'Server', 'unary_unary_rpc_method_handler',
+           'unary_stream_rpc_method_handler', 'stream_unary_rpc_method_handler',
            'stream_stream_rpc_method_handler',
            'method_handlers_generic_handler', 'ssl_channel_credentials',
            'metadata_call_credentials', 'access_token_call_credentials',
            'composite_call_credentials', 'composite_channel_credentials',
-           'ssl_server_credentials', 'ssl_server_certificate_config',
-           'ssl_server_credentials_dynamic_cert_config', 'channel_ready_future',
+           'ssl_server_credentials', 'ssl_server_certificate_configuration',
+           'dynamic_ssl_server_credentials', 'channel_ready_future',
            'insecure_channel', 'secure_channel', 'server',)
 
 ############################### Extension Shims ################################
diff --git a/src/python/grpcio/grpc/_cython/_cygrpc/credentials.pyx.pxi b/src/python/grpcio/grpc/_cython/_cygrpc/credentials.pyx.pxi
index db813b7243f..ee1328d2e9f 100644
--- a/src/python/grpcio/grpc/_cython/_cygrpc/credentials.pyx.pxi
+++ b/src/python/grpcio/grpc/_cython/_cygrpc/credentials.pyx.pxi
@@ -274,10 +274,10 @@ def call_credentials_metadata_plugin(CredentialsMetadataPlugin plugin):
   return credentials
 
 cdef const char* _get_c_pem_root_certs(pem_root_certs):
-  cdef char *c_pem_root_certs = NULL
-  if pem_root_certs is not None:
-    c_pem_root_certs = pem_root_certs
-  return c_pem_root_certs
+  if pem_root_certs is None:
+    return NULL
+  else:
+    return pem_root_certs
 
 cdef grpc_ssl_pem_key_cert_pair* _create_c_ssl_pem_key_cert_pairs(pem_key_cert_pairs):
   # return a malloc'ed grpc_ssl_pem_key_cert_pair from a _list_ of SslPemKeyCertPair
@@ -303,7 +303,7 @@ def server_credentials_ssl(pem_root_certs, pem_key_cert_pairs,
   cdef ServerCredentials credentials = ServerCredentials()
   credentials.references.append(pem_root_certs)
   credentials.references.append(pem_key_cert_pairs)
-  cdef char * c_pem_root_certs = _get_c_pem_root_certs(pem_root_certs)
+  cdef const char * c_pem_root_certs = _get_c_pem_root_certs(pem_root_certs)
   credentials.c_ssl_pem_key_cert_pairs_count = len(pem_key_cert_pairs)
   credentials.c_ssl_pem_key_cert_pairs = _create_c_ssl_pem_key_cert_pairs(pem_key_cert_pairs)
   cdef grpc_ssl_server_certificate_config *c_cert_config = NULL
@@ -338,8 +338,9 @@ def server_certificate_config_ssl(pem_root_certs, pem_key_cert_pairs):
 def server_credentials_ssl_dynamic_cert_config(initial_cert_config,
                                                cert_config_fetcher,
                                                bint force_client_auth):
-  if not isinstance(initial_cert_config, grpc.ServerCertificateConfig):
-    raise TypeError('initial_cert_config must be a grpc.ServerCertificateConfig')
+  if not isinstance(initial_cert_config, grpc.ServerCertificateConfiguration):
+    raise TypeError(
+        'initial_cert_config must be a grpc.ServerCertificateConfiguration')
   if not callable(cert_config_fetcher):
     raise TypeError('cert_config_fetcher must be callable')
   cdef ServerCredentials credentials = ServerCredentials()
diff --git a/src/python/grpcio/grpc/_cython/_cygrpc/server.pyx.pxi b/src/python/grpcio/grpc/_cython/_cygrpc/server.pyx.pxi
index 66565d084b1..5f3405936c6 100644
--- a/src/python/grpcio/grpc/_cython/_cygrpc/server.pyx.pxi
+++ b/src/python/grpcio/grpc/_cython/_cygrpc/server.pyx.pxi
@@ -28,7 +28,7 @@ cdef grpc_ssl_certificate_config_reload_status _server_cert_config_fetcher_wrapp
   if not credentials.initial_cert_config_fetched:
     # C-core is asking for the initial cert config
     credentials.initial_cert_config_fetched = True
-    cert_config = credentials.initial_cert_config._cert_config
+    cert_config = credentials.initial_cert_config._certificate_configuration
   else:
     user_cb = credentials.cert_config_fetcher
     try:
@@ -38,13 +38,15 @@ cdef grpc_ssl_certificate_config_reload_status _server_cert_config_fetcher_wrapp
       return GRPC_SSL_CERTIFICATE_CONFIG_RELOAD_FAIL
     if cert_config_wrapper is None:
       return GRPC_SSL_CERTIFICATE_CONFIG_RELOAD_UNCHANGED
-    elif not isinstance(cert_config_wrapper, grpc.ServerCertificateConfig):
-      logging.error('Error fetching certificate config: certificate '
-                    'config must be of type grpc.ServerCertificateConfig, '
-                    'not %s' % type(cert_config_wrapper).__name__)
+    elif not isinstance(
+        cert_config_wrapper, grpc.ServerCertificateConfiguration):
+      logging.error(
+          'Error fetching certificate configuration: certificate '
+          'configuration must be of type grpc.ServerCertificateConfiguration, '
+          'not %s' % type(cert_config_wrapper).__name__)
       return GRPC_SSL_CERTIFICATE_CONFIG_RELOAD_FAIL
     else:
-      cert_config = cert_config_wrapper._cert_config
+      cert_config = cert_config_wrapper._certificate_configuration
   config[0] = <grpc_ssl_server_certificate_config*>cert_config.c_cert_config
   # our caller will assume ownership of memory, so we have to recreate
   # a copy of c_cert_config here
diff --git a/src/python/grpcio_health_checking/setup.py b/src/python/grpcio_health_checking/setup.py
index 7a2e6f50276..c105f57509f 100644
--- a/src/python/grpcio_health_checking/setup.py
+++ b/src/python/grpcio_health_checking/setup.py
@@ -56,7 +56,7 @@ PACKAGE_DIRECTORIES = {
     '': '.',
 }
 
-INSTALL_REQUIRES = ('protobuf>=3.3.0',
+INSTALL_REQUIRES = ('protobuf>=3.5.0.post1',
                     'grpcio>={version}'.format(version=grpc_version.VERSION),)
 
 try:
diff --git a/src/python/grpcio_reflection/setup.py b/src/python/grpcio_reflection/setup.py
index 25312c7c0a2..760b89373af 100644
--- a/src/python/grpcio_reflection/setup.py
+++ b/src/python/grpcio_reflection/setup.py
@@ -57,7 +57,7 @@ PACKAGE_DIRECTORIES = {
     '': '.',
 }
 
-INSTALL_REQUIRES = ('protobuf>=3.3.0',
+INSTALL_REQUIRES = ('protobuf>=3.5.0.post1',
                     'grpcio>={version}'.format(version=grpc_version.VERSION),)
 
 try:
diff --git a/src/python/grpcio_testing/setup.py b/src/python/grpcio_testing/setup.py
index 0cc336abd1f..fa40424f6a2 100644
--- a/src/python/grpcio_testing/setup.py
+++ b/src/python/grpcio_testing/setup.py
@@ -28,7 +28,7 @@ PACKAGE_DIRECTORIES = {
     '': '.',
 }
 
-INSTALL_REQUIRES = ('protobuf>=3.3.0',
+INSTALL_REQUIRES = ('protobuf>=3.5.0.post1',
                     'grpcio>={version}'.format(version=grpc_version.VERSION),)
 
 setuptools.setup(
diff --git a/src/python/grpcio_tests/setup.py b/src/python/grpcio_tests/setup.py
index debe14c40e5..aeb4ea9c53d 100644
--- a/src/python/grpcio_tests/setup.py
+++ b/src/python/grpcio_tests/setup.py
@@ -41,8 +41,8 @@ INSTALL_REQUIRES = (
     'grpcio>={version}'.format(version=grpc_version.VERSION),
     'grpcio-tools>={version}'.format(version=grpc_version.VERSION),
     'grpcio-health-checking>={version}'.format(version=grpc_version.VERSION),
-    'oauth2client>=1.4.7', 'protobuf>=3.3.0', 'six>=1.10', 'google-auth>=1.0.0',
-    'requests>=2.14.2')
+    'oauth2client>=1.4.7', 'protobuf>=3.5.0.post1', 'six>=1.10',
+    'google-auth>=1.0.0', 'requests>=2.14.2')
 
 COMMAND_CLASS = {
     # Run `preprocess` *before* doing any packaging!
diff --git a/src/python/grpcio_tests/tests/unit/_api_test.py b/src/python/grpcio_tests/tests/unit/_api_test.py
index d877e0f993f..b14e8d5c753 100644
--- a/src/python/grpcio_tests/tests/unit/_api_test.py
+++ b/src/python/grpcio_tests/tests/unit/_api_test.py
@@ -30,7 +30,7 @@ class AllTest(unittest.TestCase):
             'ChannelConnectivity', 'StatusCode', 'RpcError', 'RpcContext',
             'Call', 'ChannelCredentials', 'CallCredentials',
             'AuthMetadataContext', 'AuthMetadataPluginCallback',
-            'AuthMetadataPlugin', 'ServerCertificateConfig',
+            'AuthMetadataPlugin', 'ServerCertificateConfiguration',
             'ServerCredentials', 'UnaryUnaryMultiCallable',
             'UnaryStreamMultiCallable', 'StreamUnaryMultiCallable',
             'StreamStreamMultiCallable', 'Channel', 'ServicerContext',
@@ -42,10 +42,9 @@ class AllTest(unittest.TestCase):
             'method_handlers_generic_handler', 'ssl_channel_credentials',
             'metadata_call_credentials', 'access_token_call_credentials',
             'composite_call_credentials', 'composite_channel_credentials',
-            'ssl_server_credentials', 'ssl_server_certificate_config',
-            'ssl_server_credentials_dynamic_cert_config',
-            'channel_ready_future', 'insecure_channel', 'secure_channel',
-            'server',)
+            'ssl_server_credentials', 'ssl_server_certificate_configuration',
+            'dynamic_ssl_server_credentials', 'channel_ready_future',
+            'insecure_channel', 'secure_channel', 'server',)
 
         six.assertCountEqual(self, expected_grpc_code_elements,
                              _from_grpc_import_star.GRPC_ELEMENTS)
diff --git a/src/python/grpcio_tests/tests/unit/_server_ssl_cert_config_test.py b/src/python/grpcio_tests/tests/unit/_server_ssl_cert_config_test.py
index d2f9f114a54..005d16ea757 100644
--- a/src/python/grpcio_tests/tests/unit/_server_ssl_cert_config_test.py
+++ b/src/python/grpcio_tests/tests/unit/_server_ssl_cert_config_test.py
@@ -11,11 +11,10 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-"""
-This tests server certificate rotation support.
+"""Tests server certificate rotation.
 
-Here we test various aspects of gRPC Python, and in some cases C-core
-by extension, support for server certificate rotation.
+Here we test various aspects of gRPC Python, and in some cases gRPC
+Core by extension, support for server certificate rotation.
 
 * ServerSSLCertReloadTestWithClientAuth: test ability to rotate
   server's SSL cert for use in future channels with clients while not
@@ -27,7 +26,7 @@ by extension, support for server certificate rotation.
   not authenticate the client.
 
 * ServerSSLCertReloadTestCertConfigReuse: tests gRPC Python's ability
-  to deal with user's reuse of ServerCertificateConfig instances.
+  to deal with user's reuse of ServerCertificateConfiguration instances.
 """
 
 import abc
@@ -140,14 +139,14 @@ class _ServerSSLCertReloadTest(
         services_pb2_grpc.add_FirstServiceServicer_to_server(
             _server_application.FirstServiceServicer(), self.server)
         switch_cert_on_client_num = 10
-        initial_cert_config = grpc.ssl_server_certificate_config(
+        initial_cert_config = grpc.ssl_server_certificate_configuration(
             [(SERVER_KEY_1_PEM, SERVER_CERT_CHAIN_1_PEM)],
             root_certificates=CA_2_PEM)
         self.cert_config_fetcher = CertConfigFetcher()
-        server_credentials = grpc.ssl_server_credentials_dynamic_cert_config(
+        server_credentials = grpc.dynamic_ssl_server_credentials(
             initial_cert_config,
             self.cert_config_fetcher,
-            require_client_auth=self.require_client_auth())
+            require_client_authentication=self.require_client_auth())
         self.port = self.server.add_secure_port('[::]:0', server_credentials)
         self.server.start()
 
@@ -285,7 +284,7 @@ class _ServerSSLCertReloadTest(
 
         # moment of truth!! client should reject server because the
         # server switch cert...
-        cert_config = grpc.ssl_server_certificate_config(
+        cert_config = grpc.ssl_server_certificate_configuration(
             [(SERVER_KEY_2_PEM, SERVER_CERT_CHAIN_2_PEM)],
             root_certificates=CA_1_PEM)
         self.cert_config_fetcher.reset()
@@ -362,18 +361,18 @@ class ServerSSLCertConfigFetcherParamsChecks(unittest.TestCase):
 
     def test_check_on_initial_config(self):
         with self.assertRaises(TypeError):
-            grpc.ssl_server_credentials_dynamic_cert_config(None, str)
+            grpc.dynamic_ssl_server_credentials(None, str)
         with self.assertRaises(TypeError):
-            grpc.ssl_server_credentials_dynamic_cert_config(1, str)
+            grpc.dynamic_ssl_server_credentials(1, str)
 
     def test_check_on_config_fetcher(self):
-        cert_config = grpc.ssl_server_certificate_config(
+        cert_config = grpc.ssl_server_certificate_configuration(
             [(SERVER_KEY_2_PEM, SERVER_CERT_CHAIN_2_PEM)],
             root_certificates=CA_1_PEM)
         with self.assertRaises(TypeError):
-            grpc.ssl_server_credentials_dynamic_cert_config(cert_config, None)
+            grpc.dynamic_ssl_server_credentials(cert_config, None)
         with self.assertRaises(TypeError):
-            grpc.ssl_server_credentials_dynamic_cert_config(cert_config, 1)
+            grpc.dynamic_ssl_server_credentials(cert_config, 1)
 
 
 class ServerSSLCertReloadTestWithClientAuth(_ServerSSLCertReloadTest):
@@ -393,14 +392,14 @@ class ServerSSLCertReloadTestWithoutClientAuth(_ServerSSLCertReloadTest):
 
 
 class ServerSSLCertReloadTestCertConfigReuse(_ServerSSLCertReloadTest):
-    """Ensures that `ServerCertificateConfig` instances can be reused.
+    """Ensures that `ServerCertificateConfiguration` instances can be reused.
 
-    Because C-core takes ownership of the
+    Because gRPC Core takes ownership of the
     `grpc_ssl_server_certificate_config` encapsulated by
-    `ServerCertificateConfig`, this test reuses the same
-    `ServerCertificateConfig` instances multiple times to make sure
+    `ServerCertificateConfiguration`, this test reuses the same
+    `ServerCertificateConfiguration` instances multiple times to make sure
     gRPC Python takes care of maintaining the validity of
-    `ServerCertificateConfig` instances, so that such instances can be
+    `ServerCertificateConfiguration` instances, so that such instances can be
     re-used by user application.
     """
 
@@ -411,17 +410,17 @@ class ServerSSLCertReloadTestCertConfigReuse(_ServerSSLCertReloadTest):
         self.server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
         services_pb2_grpc.add_FirstServiceServicer_to_server(
             _server_application.FirstServiceServicer(), self.server)
-        self.cert_config_A = grpc.ssl_server_certificate_config(
+        self.cert_config_A = grpc.ssl_server_certificate_configuration(
             [(SERVER_KEY_1_PEM, SERVER_CERT_CHAIN_1_PEM)],
             root_certificates=CA_2_PEM)
-        self.cert_config_B = grpc.ssl_server_certificate_config(
+        self.cert_config_B = grpc.ssl_server_certificate_configuration(
             [(SERVER_KEY_2_PEM, SERVER_CERT_CHAIN_2_PEM)],
             root_certificates=CA_1_PEM)
         self.cert_config_fetcher = CertConfigFetcher()
-        server_credentials = grpc.ssl_server_credentials_dynamic_cert_config(
+        server_credentials = grpc.dynamic_ssl_server_credentials(
             self.cert_config_A,
             self.cert_config_fetcher,
-            require_client_auth=True)
+            require_client_authentication=True)
         self.port = self.server.add_secure_port('[::]:0', server_credentials)
         self.server.start()
 
diff --git a/templates/test/core/surface/public_headers_must_be_c89.c.template b/templates/test/core/surface/public_headers_must_be_c89.c.template
index e2d3b1810a9..6e4a83666e6 100644
--- a/templates/test/core/surface/public_headers_must_be_c89.c.template
+++ b/templates/test/core/surface/public_headers_must_be_c89.c.template
@@ -48,10 +48,8 @@
   #include <stdio.h>
 
   int main(int argc, char **argv) {
-    if(argc == 12345678) {
-      % for fn in fns:
-      printf("%lx", (unsigned long) ${fn});
-      % endfor
-    }
+    % for fn in fns:
+    printf("%lx", (unsigned long) ${fn});
+    % endfor
     return 0;
   }
diff --git a/templates/tools/dockerfile/python_deps.include b/templates/tools/dockerfile/python_deps.include
index bf1f57f267a..cd1af22b43e 100644
--- a/templates/tools/dockerfile/python_deps.include
+++ b/templates/tools/dockerfile/python_deps.include
@@ -11,4 +11,4 @@ RUN apt-get update && apt-get install -y ${'\\'}
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
diff --git a/test/core/surface/public_headers_must_be_c89.c b/test/core/surface/public_headers_must_be_c89.c
index db9f902dbfd..b5a83c8eed9 100644
--- a/test/core/surface/public_headers_must_be_c89.c
+++ b/test/core/surface/public_headers_must_be_c89.c
@@ -66,288 +66,286 @@
 #include <stdio.h>
 
 int main(int argc, char **argv) {
-  if(argc == 12345678) {
-    printf("%lx", (unsigned long) grpc_compression_algorithm_parse);
-    printf("%lx", (unsigned long) grpc_compression_algorithm_name);
-    printf("%lx", (unsigned long) grpc_stream_compression_algorithm_name);
-    printf("%lx", (unsigned long) grpc_compression_algorithm_for_level);
-    printf("%lx", (unsigned long) grpc_stream_compression_algorithm_for_level);
-    printf("%lx", (unsigned long) grpc_compression_options_init);
-    printf("%lx", (unsigned long) grpc_compression_options_enable_algorithm);
-    printf("%lx", (unsigned long) grpc_compression_options_disable_algorithm);
-    printf("%lx", (unsigned long) grpc_compression_options_is_algorithm_enabled);
-    printf("%lx", (unsigned long) grpc_compression_options_is_stream_compression_algorithm_enabled);
-    printf("%lx", (unsigned long) grpc_metadata_array_init);
-    printf("%lx", (unsigned long) grpc_metadata_array_destroy);
-    printf("%lx", (unsigned long) grpc_call_details_init);
-    printf("%lx", (unsigned long) grpc_call_details_destroy);
-    printf("%lx", (unsigned long) grpc_register_plugin);
-    printf("%lx", (unsigned long) grpc_init);
-    printf("%lx", (unsigned long) grpc_shutdown);
-    printf("%lx", (unsigned long) grpc_version_string);
-    printf("%lx", (unsigned long) grpc_g_stands_for);
-    printf("%lx", (unsigned long) grpc_completion_queue_factory_lookup);
-    printf("%lx", (unsigned long) grpc_completion_queue_create_for_next);
-    printf("%lx", (unsigned long) grpc_completion_queue_create_for_pluck);
-    printf("%lx", (unsigned long) grpc_completion_queue_create);
-    printf("%lx", (unsigned long) grpc_completion_queue_next);
-    printf("%lx", (unsigned long) grpc_completion_queue_pluck);
-    printf("%lx", (unsigned long) grpc_completion_queue_shutdown);
-    printf("%lx", (unsigned long) grpc_completion_queue_destroy);
-    printf("%lx", (unsigned long) grpc_completion_queue_thread_local_cache_init);
-    printf("%lx", (unsigned long) grpc_completion_queue_thread_local_cache_flush);
-    printf("%lx", (unsigned long) grpc_alarm_create);
-    printf("%lx", (unsigned long) grpc_alarm_set);
-    printf("%lx", (unsigned long) grpc_alarm_cancel);
-    printf("%lx", (unsigned long) grpc_alarm_destroy);
-    printf("%lx", (unsigned long) grpc_channel_check_connectivity_state);
-    printf("%lx", (unsigned long) grpc_channel_num_external_connectivity_watchers);
-    printf("%lx", (unsigned long) grpc_channel_watch_connectivity_state);
-    printf("%lx", (unsigned long) grpc_channel_support_connectivity_watcher);
-    printf("%lx", (unsigned long) grpc_channel_create_call);
-    printf("%lx", (unsigned long) grpc_channel_ping);
-    printf("%lx", (unsigned long) grpc_channel_register_call);
-    printf("%lx", (unsigned long) grpc_channel_create_registered_call);
-    printf("%lx", (unsigned long) grpc_call_arena_alloc);
-    printf("%lx", (unsigned long) grpc_call_start_batch);
-    printf("%lx", (unsigned long) grpc_call_get_peer);
-    printf("%lx", (unsigned long) grpc_census_call_set_context);
-    printf("%lx", (unsigned long) grpc_census_call_get_context);
-    printf("%lx", (unsigned long) grpc_channel_get_target);
-    printf("%lx", (unsigned long) grpc_channel_get_info);
-    printf("%lx", (unsigned long) grpc_insecure_channel_create);
-    printf("%lx", (unsigned long) grpc_lame_client_channel_create);
-    printf("%lx", (unsigned long) grpc_channel_destroy);
-    printf("%lx", (unsigned long) grpc_call_cancel);
-    printf("%lx", (unsigned long) grpc_call_cancel_with_status);
-    printf("%lx", (unsigned long) grpc_call_ref);
-    printf("%lx", (unsigned long) grpc_call_unref);
-    printf("%lx", (unsigned long) grpc_server_request_call);
-    printf("%lx", (unsigned long) grpc_server_register_method);
-    printf("%lx", (unsigned long) grpc_server_request_registered_call);
-    printf("%lx", (unsigned long) grpc_server_create);
-    printf("%lx", (unsigned long) grpc_server_register_completion_queue);
-    printf("%lx", (unsigned long) grpc_server_add_insecure_http2_port);
-    printf("%lx", (unsigned long) grpc_server_start);
-    printf("%lx", (unsigned long) grpc_server_shutdown_and_notify);
-    printf("%lx", (unsigned long) grpc_server_cancel_all_calls);
-    printf("%lx", (unsigned long) grpc_server_destroy);
-    printf("%lx", (unsigned long) grpc_tracer_set_enabled);
-    printf("%lx", (unsigned long) grpc_header_key_is_legal);
-    printf("%lx", (unsigned long) grpc_header_nonbin_value_is_legal);
-    printf("%lx", (unsigned long) grpc_is_binary_header);
-    printf("%lx", (unsigned long) grpc_call_error_to_string);
-    printf("%lx", (unsigned long) grpc_resource_quota_create);
-    printf("%lx", (unsigned long) grpc_resource_quota_ref);
-    printf("%lx", (unsigned long) grpc_resource_quota_unref);
-    printf("%lx", (unsigned long) grpc_resource_quota_resize);
-    printf("%lx", (unsigned long) grpc_resource_quota_arg_vtable);
-    printf("%lx", (unsigned long) grpc_auth_property_iterator_next);
-    printf("%lx", (unsigned long) grpc_auth_context_property_iterator);
-    printf("%lx", (unsigned long) grpc_auth_context_peer_identity);
-    printf("%lx", (unsigned long) grpc_auth_context_find_properties_by_name);
-    printf("%lx", (unsigned long) grpc_auth_context_peer_identity_property_name);
-    printf("%lx", (unsigned long) grpc_auth_context_peer_is_authenticated);
-    printf("%lx", (unsigned long) grpc_call_auth_context);
-    printf("%lx", (unsigned long) grpc_auth_context_release);
-    printf("%lx", (unsigned long) grpc_auth_context_add_property);
-    printf("%lx", (unsigned long) grpc_auth_context_add_cstring_property);
-    printf("%lx", (unsigned long) grpc_auth_context_set_peer_identity_property_name);
-    printf("%lx", (unsigned long) grpc_channel_credentials_release);
-    printf("%lx", (unsigned long) grpc_google_default_credentials_create);
-    printf("%lx", (unsigned long) grpc_set_ssl_roots_override_callback);
-    printf("%lx", (unsigned long) grpc_ssl_credentials_create);
-    printf("%lx", (unsigned long) grpc_call_credentials_release);
-    printf("%lx", (unsigned long) grpc_composite_channel_credentials_create);
-    printf("%lx", (unsigned long) grpc_composite_call_credentials_create);
-    printf("%lx", (unsigned long) grpc_google_compute_engine_credentials_create);
-    printf("%lx", (unsigned long) grpc_max_auth_token_lifetime);
-    printf("%lx", (unsigned long) grpc_service_account_jwt_access_credentials_create);
-    printf("%lx", (unsigned long) grpc_google_refresh_token_credentials_create);
-    printf("%lx", (unsigned long) grpc_access_token_credentials_create);
-    printf("%lx", (unsigned long) grpc_google_iam_credentials_create);
-    printf("%lx", (unsigned long) grpc_metadata_credentials_create_from_plugin);
-    printf("%lx", (unsigned long) grpc_secure_channel_create);
-    printf("%lx", (unsigned long) grpc_server_credentials_release);
-    printf("%lx", (unsigned long) grpc_ssl_server_certificate_config_create);
-    printf("%lx", (unsigned long) grpc_ssl_server_certificate_config_destroy);
-    printf("%lx", (unsigned long) grpc_ssl_server_credentials_create);
-    printf("%lx", (unsigned long) grpc_ssl_server_credentials_create_ex);
-    printf("%lx", (unsigned long) grpc_ssl_server_credentials_create_options_using_config);
-    printf("%lx", (unsigned long) grpc_ssl_server_credentials_create_options_using_config_fetcher);
-    printf("%lx", (unsigned long) grpc_ssl_server_credentials_options_destroy);
-    printf("%lx", (unsigned long) grpc_ssl_server_credentials_create_with_options);
-    printf("%lx", (unsigned long) grpc_server_add_secure_http2_port);
-    printf("%lx", (unsigned long) grpc_call_set_credentials);
-    printf("%lx", (unsigned long) grpc_server_credentials_set_auth_metadata_processor);
-    printf("%lx", (unsigned long) grpc_raw_byte_buffer_create);
-    printf("%lx", (unsigned long) grpc_raw_compressed_byte_buffer_create);
-    printf("%lx", (unsigned long) grpc_byte_buffer_copy);
-    printf("%lx", (unsigned long) grpc_byte_buffer_length);
-    printf("%lx", (unsigned long) grpc_byte_buffer_destroy);
-    printf("%lx", (unsigned long) grpc_byte_buffer_reader_init);
-    printf("%lx", (unsigned long) grpc_byte_buffer_reader_destroy);
-    printf("%lx", (unsigned long) grpc_byte_buffer_reader_next);
-    printf("%lx", (unsigned long) grpc_byte_buffer_reader_readall);
-    printf("%lx", (unsigned long) grpc_raw_byte_buffer_from_reader);
-    printf("%lx", (unsigned long) grpc_slice_ref);
-    printf("%lx", (unsigned long) grpc_slice_unref);
-    printf("%lx", (unsigned long) grpc_slice_copy);
-    printf("%lx", (unsigned long) grpc_slice_new);
-    printf("%lx", (unsigned long) grpc_slice_new_with_user_data);
-    printf("%lx", (unsigned long) grpc_slice_new_with_len);
-    printf("%lx", (unsigned long) grpc_slice_malloc);
-    printf("%lx", (unsigned long) grpc_slice_malloc_large);
-    printf("%lx", (unsigned long) grpc_slice_intern);
-    printf("%lx", (unsigned long) grpc_slice_from_copied_string);
-    printf("%lx", (unsigned long) grpc_slice_from_copied_buffer);
-    printf("%lx", (unsigned long) grpc_slice_from_static_string);
-    printf("%lx", (unsigned long) grpc_slice_from_static_buffer);
-    printf("%lx", (unsigned long) grpc_slice_sub);
-    printf("%lx", (unsigned long) grpc_slice_sub_no_ref);
-    printf("%lx", (unsigned long) grpc_slice_split_tail);
-    printf("%lx", (unsigned long) grpc_slice_split_tail_maybe_ref);
-    printf("%lx", (unsigned long) grpc_slice_split_head);
-    printf("%lx", (unsigned long) grpc_empty_slice);
-    printf("%lx", (unsigned long) grpc_slice_default_hash_impl);
-    printf("%lx", (unsigned long) grpc_slice_default_eq_impl);
-    printf("%lx", (unsigned long) grpc_slice_eq);
-    printf("%lx", (unsigned long) grpc_slice_cmp);
-    printf("%lx", (unsigned long) grpc_slice_str_cmp);
-    printf("%lx", (unsigned long) grpc_slice_buf_start_eq);
-    printf("%lx", (unsigned long) grpc_slice_rchr);
-    printf("%lx", (unsigned long) grpc_slice_chr);
-    printf("%lx", (unsigned long) grpc_slice_slice);
-    printf("%lx", (unsigned long) grpc_slice_hash);
-    printf("%lx", (unsigned long) grpc_slice_is_equivalent);
-    printf("%lx", (unsigned long) grpc_slice_dup);
-    printf("%lx", (unsigned long) grpc_slice_to_c_string);
-    printf("%lx", (unsigned long) grpc_slice_buffer_init);
-    printf("%lx", (unsigned long) grpc_slice_buffer_destroy);
-    printf("%lx", (unsigned long) grpc_slice_buffer_add);
-    printf("%lx", (unsigned long) grpc_slice_buffer_add_indexed);
-    printf("%lx", (unsigned long) grpc_slice_buffer_addn);
-    printf("%lx", (unsigned long) grpc_slice_buffer_tiny_add);
-    printf("%lx", (unsigned long) grpc_slice_buffer_pop);
-    printf("%lx", (unsigned long) grpc_slice_buffer_reset_and_unref);
-    printf("%lx", (unsigned long) grpc_slice_buffer_swap);
-    printf("%lx", (unsigned long) grpc_slice_buffer_move_into);
-    printf("%lx", (unsigned long) grpc_slice_buffer_trim_end);
-    printf("%lx", (unsigned long) grpc_slice_buffer_move_first);
-    printf("%lx", (unsigned long) grpc_slice_buffer_move_first_no_ref);
-    printf("%lx", (unsigned long) grpc_slice_buffer_move_first_into_buffer);
-    printf("%lx", (unsigned long) grpc_slice_buffer_take_first);
-    printf("%lx", (unsigned long) grpc_slice_buffer_undo_take_first);
-    printf("%lx", (unsigned long) gpr_malloc);
-    printf("%lx", (unsigned long) gpr_zalloc);
-    printf("%lx", (unsigned long) gpr_free);
-    printf("%lx", (unsigned long) gpr_realloc);
-    printf("%lx", (unsigned long) gpr_malloc_aligned);
-    printf("%lx", (unsigned long) gpr_free_aligned);
-    printf("%lx", (unsigned long) gpr_set_allocation_functions);
-    printf("%lx", (unsigned long) gpr_get_allocation_functions);
-    printf("%lx", (unsigned long) gpr_avl_create);
-    printf("%lx", (unsigned long) gpr_avl_ref);
-    printf("%lx", (unsigned long) gpr_avl_unref);
-    printf("%lx", (unsigned long) gpr_avl_add);
-    printf("%lx", (unsigned long) gpr_avl_remove);
-    printf("%lx", (unsigned long) gpr_avl_get);
-    printf("%lx", (unsigned long) gpr_avl_maybe_get);
-    printf("%lx", (unsigned long) gpr_avl_is_empty);
-    printf("%lx", (unsigned long) gpr_cmdline_create);
-    printf("%lx", (unsigned long) gpr_cmdline_add_int);
-    printf("%lx", (unsigned long) gpr_cmdline_add_flag);
-    printf("%lx", (unsigned long) gpr_cmdline_add_string);
-    printf("%lx", (unsigned long) gpr_cmdline_on_extra_arg);
-    printf("%lx", (unsigned long) gpr_cmdline_set_survive_failure);
-    printf("%lx", (unsigned long) gpr_cmdline_parse);
-    printf("%lx", (unsigned long) gpr_cmdline_destroy);
-    printf("%lx", (unsigned long) gpr_cmdline_usage_string);
-    printf("%lx", (unsigned long) gpr_cpu_num_cores);
-    printf("%lx", (unsigned long) gpr_cpu_current_cpu);
-    printf("%lx", (unsigned long) gpr_histogram_create);
-    printf("%lx", (unsigned long) gpr_histogram_destroy);
-    printf("%lx", (unsigned long) gpr_histogram_add);
-    printf("%lx", (unsigned long) gpr_histogram_merge);
-    printf("%lx", (unsigned long) gpr_histogram_percentile);
-    printf("%lx", (unsigned long) gpr_histogram_mean);
-    printf("%lx", (unsigned long) gpr_histogram_stddev);
-    printf("%lx", (unsigned long) gpr_histogram_variance);
-    printf("%lx", (unsigned long) gpr_histogram_maximum);
-    printf("%lx", (unsigned long) gpr_histogram_minimum);
-    printf("%lx", (unsigned long) gpr_histogram_count);
-    printf("%lx", (unsigned long) gpr_histogram_sum);
-    printf("%lx", (unsigned long) gpr_histogram_sum_of_squares);
-    printf("%lx", (unsigned long) gpr_histogram_get_contents);
-    printf("%lx", (unsigned long) gpr_histogram_merge_contents);
-    printf("%lx", (unsigned long) gpr_join_host_port);
-    printf("%lx", (unsigned long) gpr_split_host_port);
-    printf("%lx", (unsigned long) gpr_log_severity_string);
-    printf("%lx", (unsigned long) gpr_log);
-    printf("%lx", (unsigned long) gpr_log_message);
-    printf("%lx", (unsigned long) gpr_set_log_verbosity);
-    printf("%lx", (unsigned long) gpr_log_verbosity_init);
-    printf("%lx", (unsigned long) gpr_set_log_function);
-    printf("%lx", (unsigned long) gpr_strdup);
-    printf("%lx", (unsigned long) gpr_asprintf);
-    printf("%lx", (unsigned long) gpr_subprocess_binary_extension);
-    printf("%lx", (unsigned long) gpr_subprocess_create);
-    printf("%lx", (unsigned long) gpr_subprocess_destroy);
-    printf("%lx", (unsigned long) gpr_subprocess_join);
-    printf("%lx", (unsigned long) gpr_subprocess_interrupt);
-    printf("%lx", (unsigned long) gpr_mu_init);
-    printf("%lx", (unsigned long) gpr_mu_destroy);
-    printf("%lx", (unsigned long) gpr_mu_lock);
-    printf("%lx", (unsigned long) gpr_mu_unlock);
-    printf("%lx", (unsigned long) gpr_mu_trylock);
-    printf("%lx", (unsigned long) gpr_cv_init);
-    printf("%lx", (unsigned long) gpr_cv_destroy);
-    printf("%lx", (unsigned long) gpr_cv_wait);
-    printf("%lx", (unsigned long) gpr_cv_signal);
-    printf("%lx", (unsigned long) gpr_cv_broadcast);
-    printf("%lx", (unsigned long) gpr_once_init);
-    printf("%lx", (unsigned long) gpr_event_init);
-    printf("%lx", (unsigned long) gpr_event_set);
-    printf("%lx", (unsigned long) gpr_event_get);
-    printf("%lx", (unsigned long) gpr_event_wait);
-    printf("%lx", (unsigned long) gpr_ref_init);
-    printf("%lx", (unsigned long) gpr_ref);
-    printf("%lx", (unsigned long) gpr_ref_non_zero);
-    printf("%lx", (unsigned long) gpr_refn);
-    printf("%lx", (unsigned long) gpr_unref);
-    printf("%lx", (unsigned long) gpr_ref_is_unique);
-    printf("%lx", (unsigned long) gpr_stats_init);
-    printf("%lx", (unsigned long) gpr_stats_inc);
-    printf("%lx", (unsigned long) gpr_stats_read);
-    printf("%lx", (unsigned long) gpr_thd_new);
-    printf("%lx", (unsigned long) gpr_thd_options_default);
-    printf("%lx", (unsigned long) gpr_thd_options_set_detached);
-    printf("%lx", (unsigned long) gpr_thd_options_set_joinable);
-    printf("%lx", (unsigned long) gpr_thd_options_is_detached);
-    printf("%lx", (unsigned long) gpr_thd_options_is_joinable);
-    printf("%lx", (unsigned long) gpr_thd_currentid);
-    printf("%lx", (unsigned long) gpr_thd_join);
-    printf("%lx", (unsigned long) gpr_time_0);
-    printf("%lx", (unsigned long) gpr_inf_future);
-    printf("%lx", (unsigned long) gpr_inf_past);
-    printf("%lx", (unsigned long) gpr_time_init);
-    printf("%lx", (unsigned long) gpr_now);
-    printf("%lx", (unsigned long) gpr_convert_clock_type);
-    printf("%lx", (unsigned long) gpr_time_cmp);
-    printf("%lx", (unsigned long) gpr_time_max);
-    printf("%lx", (unsigned long) gpr_time_min);
-    printf("%lx", (unsigned long) gpr_time_add);
-    printf("%lx", (unsigned long) gpr_time_sub);
-    printf("%lx", (unsigned long) gpr_time_from_micros);
-    printf("%lx", (unsigned long) gpr_time_from_nanos);
-    printf("%lx", (unsigned long) gpr_time_from_millis);
-    printf("%lx", (unsigned long) gpr_time_from_seconds);
-    printf("%lx", (unsigned long) gpr_time_from_minutes);
-    printf("%lx", (unsigned long) gpr_time_from_hours);
-    printf("%lx", (unsigned long) gpr_time_to_millis);
-    printf("%lx", (unsigned long) gpr_time_similar);
-    printf("%lx", (unsigned long) gpr_sleep_until);
-    printf("%lx", (unsigned long) gpr_timespec_to_micros);
-  }
+  printf("%lx", (unsigned long) grpc_compression_algorithm_parse);
+  printf("%lx", (unsigned long) grpc_compression_algorithm_name);
+  printf("%lx", (unsigned long) grpc_stream_compression_algorithm_name);
+  printf("%lx", (unsigned long) grpc_compression_algorithm_for_level);
+  printf("%lx", (unsigned long) grpc_stream_compression_algorithm_for_level);
+  printf("%lx", (unsigned long) grpc_compression_options_init);
+  printf("%lx", (unsigned long) grpc_compression_options_enable_algorithm);
+  printf("%lx", (unsigned long) grpc_compression_options_disable_algorithm);
+  printf("%lx", (unsigned long) grpc_compression_options_is_algorithm_enabled);
+  printf("%lx", (unsigned long) grpc_compression_options_is_stream_compression_algorithm_enabled);
+  printf("%lx", (unsigned long) grpc_metadata_array_init);
+  printf("%lx", (unsigned long) grpc_metadata_array_destroy);
+  printf("%lx", (unsigned long) grpc_call_details_init);
+  printf("%lx", (unsigned long) grpc_call_details_destroy);
+  printf("%lx", (unsigned long) grpc_register_plugin);
+  printf("%lx", (unsigned long) grpc_init);
+  printf("%lx", (unsigned long) grpc_shutdown);
+  printf("%lx", (unsigned long) grpc_version_string);
+  printf("%lx", (unsigned long) grpc_g_stands_for);
+  printf("%lx", (unsigned long) grpc_completion_queue_factory_lookup);
+  printf("%lx", (unsigned long) grpc_completion_queue_create_for_next);
+  printf("%lx", (unsigned long) grpc_completion_queue_create_for_pluck);
+  printf("%lx", (unsigned long) grpc_completion_queue_create);
+  printf("%lx", (unsigned long) grpc_completion_queue_next);
+  printf("%lx", (unsigned long) grpc_completion_queue_pluck);
+  printf("%lx", (unsigned long) grpc_completion_queue_shutdown);
+  printf("%lx", (unsigned long) grpc_completion_queue_destroy);
+  printf("%lx", (unsigned long) grpc_completion_queue_thread_local_cache_init);
+  printf("%lx", (unsigned long) grpc_completion_queue_thread_local_cache_flush);
+  printf("%lx", (unsigned long) grpc_alarm_create);
+  printf("%lx", (unsigned long) grpc_alarm_set);
+  printf("%lx", (unsigned long) grpc_alarm_cancel);
+  printf("%lx", (unsigned long) grpc_alarm_destroy);
+  printf("%lx", (unsigned long) grpc_channel_check_connectivity_state);
+  printf("%lx", (unsigned long) grpc_channel_num_external_connectivity_watchers);
+  printf("%lx", (unsigned long) grpc_channel_watch_connectivity_state);
+  printf("%lx", (unsigned long) grpc_channel_support_connectivity_watcher);
+  printf("%lx", (unsigned long) grpc_channel_create_call);
+  printf("%lx", (unsigned long) grpc_channel_ping);
+  printf("%lx", (unsigned long) grpc_channel_register_call);
+  printf("%lx", (unsigned long) grpc_channel_create_registered_call);
+  printf("%lx", (unsigned long) grpc_call_arena_alloc);
+  printf("%lx", (unsigned long) grpc_call_start_batch);
+  printf("%lx", (unsigned long) grpc_call_get_peer);
+  printf("%lx", (unsigned long) grpc_census_call_set_context);
+  printf("%lx", (unsigned long) grpc_census_call_get_context);
+  printf("%lx", (unsigned long) grpc_channel_get_target);
+  printf("%lx", (unsigned long) grpc_channel_get_info);
+  printf("%lx", (unsigned long) grpc_insecure_channel_create);
+  printf("%lx", (unsigned long) grpc_lame_client_channel_create);
+  printf("%lx", (unsigned long) grpc_channel_destroy);
+  printf("%lx", (unsigned long) grpc_call_cancel);
+  printf("%lx", (unsigned long) grpc_call_cancel_with_status);
+  printf("%lx", (unsigned long) grpc_call_ref);
+  printf("%lx", (unsigned long) grpc_call_unref);
+  printf("%lx", (unsigned long) grpc_server_request_call);
+  printf("%lx", (unsigned long) grpc_server_register_method);
+  printf("%lx", (unsigned long) grpc_server_request_registered_call);
+  printf("%lx", (unsigned long) grpc_server_create);
+  printf("%lx", (unsigned long) grpc_server_register_completion_queue);
+  printf("%lx", (unsigned long) grpc_server_add_insecure_http2_port);
+  printf("%lx", (unsigned long) grpc_server_start);
+  printf("%lx", (unsigned long) grpc_server_shutdown_and_notify);
+  printf("%lx", (unsigned long) grpc_server_cancel_all_calls);
+  printf("%lx", (unsigned long) grpc_server_destroy);
+  printf("%lx", (unsigned long) grpc_tracer_set_enabled);
+  printf("%lx", (unsigned long) grpc_header_key_is_legal);
+  printf("%lx", (unsigned long) grpc_header_nonbin_value_is_legal);
+  printf("%lx", (unsigned long) grpc_is_binary_header);
+  printf("%lx", (unsigned long) grpc_call_error_to_string);
+  printf("%lx", (unsigned long) grpc_resource_quota_create);
+  printf("%lx", (unsigned long) grpc_resource_quota_ref);
+  printf("%lx", (unsigned long) grpc_resource_quota_unref);
+  printf("%lx", (unsigned long) grpc_resource_quota_resize);
+  printf("%lx", (unsigned long) grpc_resource_quota_arg_vtable);
+  printf("%lx", (unsigned long) grpc_auth_property_iterator_next);
+  printf("%lx", (unsigned long) grpc_auth_context_property_iterator);
+  printf("%lx", (unsigned long) grpc_auth_context_peer_identity);
+  printf("%lx", (unsigned long) grpc_auth_context_find_properties_by_name);
+  printf("%lx", (unsigned long) grpc_auth_context_peer_identity_property_name);
+  printf("%lx", (unsigned long) grpc_auth_context_peer_is_authenticated);
+  printf("%lx", (unsigned long) grpc_call_auth_context);
+  printf("%lx", (unsigned long) grpc_auth_context_release);
+  printf("%lx", (unsigned long) grpc_auth_context_add_property);
+  printf("%lx", (unsigned long) grpc_auth_context_add_cstring_property);
+  printf("%lx", (unsigned long) grpc_auth_context_set_peer_identity_property_name);
+  printf("%lx", (unsigned long) grpc_channel_credentials_release);
+  printf("%lx", (unsigned long) grpc_google_default_credentials_create);
+  printf("%lx", (unsigned long) grpc_set_ssl_roots_override_callback);
+  printf("%lx", (unsigned long) grpc_ssl_credentials_create);
+  printf("%lx", (unsigned long) grpc_call_credentials_release);
+  printf("%lx", (unsigned long) grpc_composite_channel_credentials_create);
+  printf("%lx", (unsigned long) grpc_composite_call_credentials_create);
+  printf("%lx", (unsigned long) grpc_google_compute_engine_credentials_create);
+  printf("%lx", (unsigned long) grpc_max_auth_token_lifetime);
+  printf("%lx", (unsigned long) grpc_service_account_jwt_access_credentials_create);
+  printf("%lx", (unsigned long) grpc_google_refresh_token_credentials_create);
+  printf("%lx", (unsigned long) grpc_access_token_credentials_create);
+  printf("%lx", (unsigned long) grpc_google_iam_credentials_create);
+  printf("%lx", (unsigned long) grpc_metadata_credentials_create_from_plugin);
+  printf("%lx", (unsigned long) grpc_secure_channel_create);
+  printf("%lx", (unsigned long) grpc_server_credentials_release);
+  printf("%lx", (unsigned long) grpc_ssl_server_certificate_config_create);
+  printf("%lx", (unsigned long) grpc_ssl_server_certificate_config_destroy);
+  printf("%lx", (unsigned long) grpc_ssl_server_credentials_create);
+  printf("%lx", (unsigned long) grpc_ssl_server_credentials_create_ex);
+  printf("%lx", (unsigned long) grpc_ssl_server_credentials_create_options_using_config);
+  printf("%lx", (unsigned long) grpc_ssl_server_credentials_create_options_using_config_fetcher);
+  printf("%lx", (unsigned long) grpc_ssl_server_credentials_options_destroy);
+  printf("%lx", (unsigned long) grpc_ssl_server_credentials_create_with_options);
+  printf("%lx", (unsigned long) grpc_server_add_secure_http2_port);
+  printf("%lx", (unsigned long) grpc_call_set_credentials);
+  printf("%lx", (unsigned long) grpc_server_credentials_set_auth_metadata_processor);
+  printf("%lx", (unsigned long) grpc_raw_byte_buffer_create);
+  printf("%lx", (unsigned long) grpc_raw_compressed_byte_buffer_create);
+  printf("%lx", (unsigned long) grpc_byte_buffer_copy);
+  printf("%lx", (unsigned long) grpc_byte_buffer_length);
+  printf("%lx", (unsigned long) grpc_byte_buffer_destroy);
+  printf("%lx", (unsigned long) grpc_byte_buffer_reader_init);
+  printf("%lx", (unsigned long) grpc_byte_buffer_reader_destroy);
+  printf("%lx", (unsigned long) grpc_byte_buffer_reader_next);
+  printf("%lx", (unsigned long) grpc_byte_buffer_reader_readall);
+  printf("%lx", (unsigned long) grpc_raw_byte_buffer_from_reader);
+  printf("%lx", (unsigned long) grpc_slice_ref);
+  printf("%lx", (unsigned long) grpc_slice_unref);
+  printf("%lx", (unsigned long) grpc_slice_copy);
+  printf("%lx", (unsigned long) grpc_slice_new);
+  printf("%lx", (unsigned long) grpc_slice_new_with_user_data);
+  printf("%lx", (unsigned long) grpc_slice_new_with_len);
+  printf("%lx", (unsigned long) grpc_slice_malloc);
+  printf("%lx", (unsigned long) grpc_slice_malloc_large);
+  printf("%lx", (unsigned long) grpc_slice_intern);
+  printf("%lx", (unsigned long) grpc_slice_from_copied_string);
+  printf("%lx", (unsigned long) grpc_slice_from_copied_buffer);
+  printf("%lx", (unsigned long) grpc_slice_from_static_string);
+  printf("%lx", (unsigned long) grpc_slice_from_static_buffer);
+  printf("%lx", (unsigned long) grpc_slice_sub);
+  printf("%lx", (unsigned long) grpc_slice_sub_no_ref);
+  printf("%lx", (unsigned long) grpc_slice_split_tail);
+  printf("%lx", (unsigned long) grpc_slice_split_tail_maybe_ref);
+  printf("%lx", (unsigned long) grpc_slice_split_head);
+  printf("%lx", (unsigned long) grpc_empty_slice);
+  printf("%lx", (unsigned long) grpc_slice_default_hash_impl);
+  printf("%lx", (unsigned long) grpc_slice_default_eq_impl);
+  printf("%lx", (unsigned long) grpc_slice_eq);
+  printf("%lx", (unsigned long) grpc_slice_cmp);
+  printf("%lx", (unsigned long) grpc_slice_str_cmp);
+  printf("%lx", (unsigned long) grpc_slice_buf_start_eq);
+  printf("%lx", (unsigned long) grpc_slice_rchr);
+  printf("%lx", (unsigned long) grpc_slice_chr);
+  printf("%lx", (unsigned long) grpc_slice_slice);
+  printf("%lx", (unsigned long) grpc_slice_hash);
+  printf("%lx", (unsigned long) grpc_slice_is_equivalent);
+  printf("%lx", (unsigned long) grpc_slice_dup);
+  printf("%lx", (unsigned long) grpc_slice_to_c_string);
+  printf("%lx", (unsigned long) grpc_slice_buffer_init);
+  printf("%lx", (unsigned long) grpc_slice_buffer_destroy);
+  printf("%lx", (unsigned long) grpc_slice_buffer_add);
+  printf("%lx", (unsigned long) grpc_slice_buffer_add_indexed);
+  printf("%lx", (unsigned long) grpc_slice_buffer_addn);
+  printf("%lx", (unsigned long) grpc_slice_buffer_tiny_add);
+  printf("%lx", (unsigned long) grpc_slice_buffer_pop);
+  printf("%lx", (unsigned long) grpc_slice_buffer_reset_and_unref);
+  printf("%lx", (unsigned long) grpc_slice_buffer_swap);
+  printf("%lx", (unsigned long) grpc_slice_buffer_move_into);
+  printf("%lx", (unsigned long) grpc_slice_buffer_trim_end);
+  printf("%lx", (unsigned long) grpc_slice_buffer_move_first);
+  printf("%lx", (unsigned long) grpc_slice_buffer_move_first_no_ref);
+  printf("%lx", (unsigned long) grpc_slice_buffer_move_first_into_buffer);
+  printf("%lx", (unsigned long) grpc_slice_buffer_take_first);
+  printf("%lx", (unsigned long) grpc_slice_buffer_undo_take_first);
+  printf("%lx", (unsigned long) gpr_malloc);
+  printf("%lx", (unsigned long) gpr_zalloc);
+  printf("%lx", (unsigned long) gpr_free);
+  printf("%lx", (unsigned long) gpr_realloc);
+  printf("%lx", (unsigned long) gpr_malloc_aligned);
+  printf("%lx", (unsigned long) gpr_free_aligned);
+  printf("%lx", (unsigned long) gpr_set_allocation_functions);
+  printf("%lx", (unsigned long) gpr_get_allocation_functions);
+  printf("%lx", (unsigned long) gpr_avl_create);
+  printf("%lx", (unsigned long) gpr_avl_ref);
+  printf("%lx", (unsigned long) gpr_avl_unref);
+  printf("%lx", (unsigned long) gpr_avl_add);
+  printf("%lx", (unsigned long) gpr_avl_remove);
+  printf("%lx", (unsigned long) gpr_avl_get);
+  printf("%lx", (unsigned long) gpr_avl_maybe_get);
+  printf("%lx", (unsigned long) gpr_avl_is_empty);
+  printf("%lx", (unsigned long) gpr_cmdline_create);
+  printf("%lx", (unsigned long) gpr_cmdline_add_int);
+  printf("%lx", (unsigned long) gpr_cmdline_add_flag);
+  printf("%lx", (unsigned long) gpr_cmdline_add_string);
+  printf("%lx", (unsigned long) gpr_cmdline_on_extra_arg);
+  printf("%lx", (unsigned long) gpr_cmdline_set_survive_failure);
+  printf("%lx", (unsigned long) gpr_cmdline_parse);
+  printf("%lx", (unsigned long) gpr_cmdline_destroy);
+  printf("%lx", (unsigned long) gpr_cmdline_usage_string);
+  printf("%lx", (unsigned long) gpr_cpu_num_cores);
+  printf("%lx", (unsigned long) gpr_cpu_current_cpu);
+  printf("%lx", (unsigned long) gpr_histogram_create);
+  printf("%lx", (unsigned long) gpr_histogram_destroy);
+  printf("%lx", (unsigned long) gpr_histogram_add);
+  printf("%lx", (unsigned long) gpr_histogram_merge);
+  printf("%lx", (unsigned long) gpr_histogram_percentile);
+  printf("%lx", (unsigned long) gpr_histogram_mean);
+  printf("%lx", (unsigned long) gpr_histogram_stddev);
+  printf("%lx", (unsigned long) gpr_histogram_variance);
+  printf("%lx", (unsigned long) gpr_histogram_maximum);
+  printf("%lx", (unsigned long) gpr_histogram_minimum);
+  printf("%lx", (unsigned long) gpr_histogram_count);
+  printf("%lx", (unsigned long) gpr_histogram_sum);
+  printf("%lx", (unsigned long) gpr_histogram_sum_of_squares);
+  printf("%lx", (unsigned long) gpr_histogram_get_contents);
+  printf("%lx", (unsigned long) gpr_histogram_merge_contents);
+  printf("%lx", (unsigned long) gpr_join_host_port);
+  printf("%lx", (unsigned long) gpr_split_host_port);
+  printf("%lx", (unsigned long) gpr_log_severity_string);
+  printf("%lx", (unsigned long) gpr_log);
+  printf("%lx", (unsigned long) gpr_log_message);
+  printf("%lx", (unsigned long) gpr_set_log_verbosity);
+  printf("%lx", (unsigned long) gpr_log_verbosity_init);
+  printf("%lx", (unsigned long) gpr_set_log_function);
+  printf("%lx", (unsigned long) gpr_strdup);
+  printf("%lx", (unsigned long) gpr_asprintf);
+  printf("%lx", (unsigned long) gpr_subprocess_binary_extension);
+  printf("%lx", (unsigned long) gpr_subprocess_create);
+  printf("%lx", (unsigned long) gpr_subprocess_destroy);
+  printf("%lx", (unsigned long) gpr_subprocess_join);
+  printf("%lx", (unsigned long) gpr_subprocess_interrupt);
+  printf("%lx", (unsigned long) gpr_mu_init);
+  printf("%lx", (unsigned long) gpr_mu_destroy);
+  printf("%lx", (unsigned long) gpr_mu_lock);
+  printf("%lx", (unsigned long) gpr_mu_unlock);
+  printf("%lx", (unsigned long) gpr_mu_trylock);
+  printf("%lx", (unsigned long) gpr_cv_init);
+  printf("%lx", (unsigned long) gpr_cv_destroy);
+  printf("%lx", (unsigned long) gpr_cv_wait);
+  printf("%lx", (unsigned long) gpr_cv_signal);
+  printf("%lx", (unsigned long) gpr_cv_broadcast);
+  printf("%lx", (unsigned long) gpr_once_init);
+  printf("%lx", (unsigned long) gpr_event_init);
+  printf("%lx", (unsigned long) gpr_event_set);
+  printf("%lx", (unsigned long) gpr_event_get);
+  printf("%lx", (unsigned long) gpr_event_wait);
+  printf("%lx", (unsigned long) gpr_ref_init);
+  printf("%lx", (unsigned long) gpr_ref);
+  printf("%lx", (unsigned long) gpr_ref_non_zero);
+  printf("%lx", (unsigned long) gpr_refn);
+  printf("%lx", (unsigned long) gpr_unref);
+  printf("%lx", (unsigned long) gpr_ref_is_unique);
+  printf("%lx", (unsigned long) gpr_stats_init);
+  printf("%lx", (unsigned long) gpr_stats_inc);
+  printf("%lx", (unsigned long) gpr_stats_read);
+  printf("%lx", (unsigned long) gpr_thd_new);
+  printf("%lx", (unsigned long) gpr_thd_options_default);
+  printf("%lx", (unsigned long) gpr_thd_options_set_detached);
+  printf("%lx", (unsigned long) gpr_thd_options_set_joinable);
+  printf("%lx", (unsigned long) gpr_thd_options_is_detached);
+  printf("%lx", (unsigned long) gpr_thd_options_is_joinable);
+  printf("%lx", (unsigned long) gpr_thd_currentid);
+  printf("%lx", (unsigned long) gpr_thd_join);
+  printf("%lx", (unsigned long) gpr_time_0);
+  printf("%lx", (unsigned long) gpr_inf_future);
+  printf("%lx", (unsigned long) gpr_inf_past);
+  printf("%lx", (unsigned long) gpr_time_init);
+  printf("%lx", (unsigned long) gpr_now);
+  printf("%lx", (unsigned long) gpr_convert_clock_type);
+  printf("%lx", (unsigned long) gpr_time_cmp);
+  printf("%lx", (unsigned long) gpr_time_max);
+  printf("%lx", (unsigned long) gpr_time_min);
+  printf("%lx", (unsigned long) gpr_time_add);
+  printf("%lx", (unsigned long) gpr_time_sub);
+  printf("%lx", (unsigned long) gpr_time_from_micros);
+  printf("%lx", (unsigned long) gpr_time_from_nanos);
+  printf("%lx", (unsigned long) gpr_time_from_millis);
+  printf("%lx", (unsigned long) gpr_time_from_seconds);
+  printf("%lx", (unsigned long) gpr_time_from_minutes);
+  printf("%lx", (unsigned long) gpr_time_from_hours);
+  printf("%lx", (unsigned long) gpr_time_to_millis);
+  printf("%lx", (unsigned long) gpr_time_similar);
+  printf("%lx", (unsigned long) gpr_sleep_until);
+  printf("%lx", (unsigned long) gpr_timespec_to_micros);
   return 0;
 }
diff --git a/test/core/util/grpc_fuzzer.bzl b/test/core/util/grpc_fuzzer.bzl
index 55b6f1c1a5e..b8b270ecd0c 100644
--- a/test/core/util/grpc_fuzzer.bzl
+++ b/test/core/util/grpc_fuzzer.bzl
@@ -19,8 +19,7 @@ def grpc_fuzzer(name, corpus, srcs = [], deps = [], **kwargs):
     name = name,
     srcs = srcs,
     deps = deps + ["//test/core/util:fuzzer_corpus_test"],
-    data = [corpus],
-    args = ['--directory', '$(location %s)' % corpus],
+    data = native.glob([corpus + "/**"]),
     external_deps = [
       'gtest',
     ],
diff --git a/third_party/protobuf b/third_party/protobuf
index 80a37e0782d..2761122b810 160000
--- a/third_party/protobuf
+++ b/third_party/protobuf
@@ -1 +1 @@
-Subproject commit 80a37e0782d2d702d52234b62dd4b9ec74fd2c95
+Subproject commit 2761122b810fe8861004ae785cc3ab39f384d342
diff --git a/tools/codegen/core/gen_nano_proto.sh b/tools/codegen/core/gen_nano_proto.sh
index db00bd937f7..42468401732 100755
--- a/tools/codegen/core/gen_nano_proto.sh
+++ b/tools/codegen/core/gen_nano_proto.sh
@@ -68,7 +68,7 @@ popd
 
 # this should be the same version as the submodule we compile against
 # ideally we'd update this as a template to ensure that
-pip install protobuf==3.2.0
+pip install protobuf==3.5.0.post1
 
 pushd "$(dirname $INPUT_PROTO)" > /dev/null
 
diff --git a/tools/distrib/python/grpcio_tools/protoc_lib_deps.py b/tools/distrib/python/grpcio_tools/protoc_lib_deps.py
index 2a42a518fcd..2c65fca628e 100644
--- a/tools/distrib/python/grpcio_tools/protoc_lib_deps.py
+++ b/tools/distrib/python/grpcio_tools/protoc_lib_deps.py
@@ -14,10 +14,10 @@
 # limitations under the License.
 
 # AUTO-GENERATED BY make_grpcio_tools.py!
-CC_FILES=['google/protobuf/compiler/zip_writer.cc', 'google/protobuf/compiler/subprocess.cc', 'google/protobuf/compiler/ruby/ruby_generator.cc', 'google/protobuf/compiler/python/python_generator.cc', 'google/protobuf/compiler/plugin.pb.cc', 'google/protobuf/compiler/plugin.cc', 'google/protobuf/compiler/php/php_generator.cc', 'google/protobuf/compiler/objectivec/objectivec_primitive_field.cc', 'google/protobuf/compiler/objectivec/objectivec_oneof.cc', 'google/protobuf/compiler/objectivec/objectivec_message_field.cc', 'google/protobuf/compiler/objectivec/objectivec_message.cc', 'google/protobuf/compiler/objectivec/objectivec_map_field.cc', 'google/protobuf/compiler/objectivec/objectivec_helpers.cc', 'google/protobuf/compiler/objectivec/objectivec_generator.cc', 'google/protobuf/compiler/objectivec/objectivec_file.cc', 'google/protobuf/compiler/objectivec/objectivec_field.cc', 'google/protobuf/compiler/objectivec/objectivec_extension.cc', 'google/protobuf/compiler/objectivec/objectivec_enum_field.cc', 'google/protobuf/compiler/objectivec/objectivec_enum.cc', 'google/protobuf/compiler/js/well_known_types_embed.cc', 'google/protobuf/compiler/js/js_generator.cc', 'google/protobuf/compiler/javanano/javanano_primitive_field.cc', 'google/protobuf/compiler/javanano/javanano_message_field.cc', 'google/protobuf/compiler/javanano/javanano_message.cc', 'google/protobuf/compiler/javanano/javanano_map_field.cc', 'google/protobuf/compiler/javanano/javanano_helpers.cc', 'google/protobuf/compiler/javanano/javanano_generator.cc', 'google/protobuf/compiler/javanano/javanano_file.cc', 'google/protobuf/compiler/javanano/javanano_field.cc', 'google/protobuf/compiler/javanano/javanano_extension.cc', 'google/protobuf/compiler/javanano/javanano_enum_field.cc', 'google/protobuf/compiler/javanano/javanano_enum.cc', 'google/protobuf/compiler/java/java_string_field_lite.cc', 'google/protobuf/compiler/java/java_string_field.cc', 'google/protobuf/compiler/java/java_shared_code_generator.cc', 'google/protobuf/compiler/java/java_service.cc', 'google/protobuf/compiler/java/java_primitive_field_lite.cc', 'google/protobuf/compiler/java/java_primitive_field.cc', 'google/protobuf/compiler/java/java_name_resolver.cc', 'google/protobuf/compiler/java/java_message_lite.cc', 'google/protobuf/compiler/java/java_message_field_lite.cc', 'google/protobuf/compiler/java/java_message_field.cc', 'google/protobuf/compiler/java/java_message_builder_lite.cc', 'google/protobuf/compiler/java/java_message_builder.cc', 'google/protobuf/compiler/java/java_message.cc', 'google/protobuf/compiler/java/java_map_field_lite.cc', 'google/protobuf/compiler/java/java_map_field.cc', 'google/protobuf/compiler/java/java_lazy_message_field_lite.cc', 'google/protobuf/compiler/java/java_lazy_message_field.cc', 'google/protobuf/compiler/java/java_helpers.cc', 'google/protobuf/compiler/java/java_generator_factory.cc', 'google/protobuf/compiler/java/java_generator.cc', 'google/protobuf/compiler/java/java_file.cc', 'google/protobuf/compiler/java/java_field.cc', 'google/protobuf/compiler/java/java_extension_lite.cc', 'google/protobuf/compiler/java/java_extension.cc', 'google/protobuf/compiler/java/java_enum_lite.cc', 'google/protobuf/compiler/java/java_enum_field_lite.cc', 'google/protobuf/compiler/java/java_enum_field.cc', 'google/protobuf/compiler/java/java_enum.cc', 'google/protobuf/compiler/java/java_doc_comment.cc', 'google/protobuf/compiler/java/java_context.cc', 'google/protobuf/compiler/csharp/csharp_wrapper_field.cc', 'google/protobuf/compiler/csharp/csharp_source_generator_base.cc', 'google/protobuf/compiler/csharp/csharp_repeated_primitive_field.cc', 'google/protobuf/compiler/csharp/csharp_repeated_message_field.cc', 'google/protobuf/compiler/csharp/csharp_repeated_enum_field.cc', 'google/protobuf/compiler/csharp/csharp_reflection_class.cc', 'google/protobuf/compiler/csharp/csharp_primitive_field.cc', 'google/protobuf/compiler/csharp/csharp_message_field.cc', 'google/protobuf/compiler/csharp/csharp_message.cc', 'google/protobuf/compiler/csharp/csharp_map_field.cc', 'google/protobuf/compiler/csharp/csharp_helpers.cc', 'google/protobuf/compiler/csharp/csharp_generator.cc', 'google/protobuf/compiler/csharp/csharp_field_base.cc', 'google/protobuf/compiler/csharp/csharp_enum_field.cc', 'google/protobuf/compiler/csharp/csharp_enum.cc', 'google/protobuf/compiler/csharp/csharp_doc_comment.cc', 'google/protobuf/compiler/cpp/cpp_string_field.cc', 'google/protobuf/compiler/cpp/cpp_service.cc', 'google/protobuf/compiler/cpp/cpp_primitive_field.cc', 'google/protobuf/compiler/cpp/cpp_message_field.cc', 'google/protobuf/compiler/cpp/cpp_message.cc', 'google/protobuf/compiler/cpp/cpp_map_field.cc', 'google/protobuf/compiler/cpp/cpp_helpers.cc', 'google/protobuf/compiler/cpp/cpp_generator.cc', 'google/protobuf/compiler/cpp/cpp_file.cc', 'google/protobuf/compiler/cpp/cpp_field.cc', 'google/protobuf/compiler/cpp/cpp_extension.cc', 'google/protobuf/compiler/cpp/cpp_enum_field.cc', 'google/protobuf/compiler/cpp/cpp_enum.cc', 'google/protobuf/compiler/command_line_interface.cc', 'google/protobuf/compiler/code_generator.cc', 'google/protobuf/wrappers.pb.cc', 'google/protobuf/wire_format.cc', 'google/protobuf/util/type_resolver_util.cc', 'google/protobuf/util/time_util.cc', 'google/protobuf/util/message_differencer.cc', 'google/protobuf/util/json_util.cc', 'google/protobuf/util/internal/utility.cc', 'google/protobuf/util/internal/type_info_test_helper.cc', 'google/protobuf/util/internal/type_info.cc', 'google/protobuf/util/internal/protostream_objectwriter.cc', 'google/protobuf/util/internal/protostream_objectsource.cc', 'google/protobuf/util/internal/proto_writer.cc', 'google/protobuf/util/internal/object_writer.cc', 'google/protobuf/util/internal/json_stream_parser.cc', 'google/protobuf/util/internal/json_objectwriter.cc', 'google/protobuf/util/internal/json_escaping.cc', 'google/protobuf/util/internal/field_mask_utility.cc', 'google/protobuf/util/internal/error_listener.cc', 'google/protobuf/util/internal/default_value_objectwriter.cc', 'google/protobuf/util/internal/datapiece.cc', 'google/protobuf/util/field_mask_util.cc', 'google/protobuf/util/field_comparator.cc', 'google/protobuf/util/delimited_message_util.cc', 'google/protobuf/unknown_field_set.cc', 'google/protobuf/type.pb.cc', 'google/protobuf/timestamp.pb.cc', 'google/protobuf/text_format.cc', 'google/protobuf/stubs/substitute.cc', 'google/protobuf/stubs/mathlimits.cc', 'google/protobuf/struct.pb.cc', 'google/protobuf/source_context.pb.cc', 'google/protobuf/service.cc', 'google/protobuf/reflection_ops.cc', 'google/protobuf/message.cc', 'google/protobuf/map_field.cc', 'google/protobuf/io/zero_copy_stream_impl.cc', 'google/protobuf/io/tokenizer.cc', 'google/protobuf/io/strtod.cc', 'google/protobuf/io/printer.cc', 'google/protobuf/io/gzip_stream.cc', 'google/protobuf/generated_message_table_driven.cc', 'google/protobuf/generated_message_reflection.cc', 'google/protobuf/field_mask.pb.cc', 'google/protobuf/extension_set_heavy.cc', 'google/protobuf/empty.pb.cc', 'google/protobuf/dynamic_message.cc', 'google/protobuf/duration.pb.cc', 'google/protobuf/descriptor_database.cc', 'google/protobuf/descriptor.pb.cc', 'google/protobuf/descriptor.cc', 'google/protobuf/compiler/parser.cc', 'google/protobuf/compiler/importer.cc', 'google/protobuf/api.pb.cc', 'google/protobuf/any.pb.cc', 'google/protobuf/any.cc', 'google/protobuf/wire_format_lite.cc', 'google/protobuf/stubs/time.cc', 'google/protobuf/stubs/strutil.cc', 'google/protobuf/stubs/structurally_valid.cc', 'google/protobuf/stubs/stringprintf.cc', 'google/protobuf/stubs/stringpiece.cc', 'google/protobuf/stubs/statusor.cc', 'google/protobuf/stubs/status.cc', 'google/protobuf/stubs/once.cc', 'google/protobuf/stubs/io_win32.cc', 'google/protobuf/stubs/int128.cc', 'google/protobuf/stubs/common.cc', 'google/protobuf/stubs/bytestream.cc', 'google/protobuf/stubs/atomicops_internals_x86_msvc.cc', 'google/protobuf/stubs/atomicops_internals_x86_gcc.cc', 'google/protobuf/repeated_field.cc', 'google/protobuf/message_lite.cc', 'google/protobuf/io/zero_copy_stream_impl_lite.cc', 'google/protobuf/io/zero_copy_stream.cc', 'google/protobuf/io/coded_stream.cc', 'google/protobuf/generated_message_util.cc', 'google/protobuf/generated_message_table_driven_lite.cc', 'google/protobuf/extension_set.cc', 'google/protobuf/arenastring.cc', 'google/protobuf/arena.cc', 'google/protobuf/compiler/js/embed.cc']
+CC_FILES=['google/protobuf/compiler/zip_writer.cc', 'google/protobuf/compiler/subprocess.cc', 'google/protobuf/compiler/ruby/ruby_generator.cc', 'google/protobuf/compiler/python/python_generator.cc', 'google/protobuf/compiler/plugin.pb.cc', 'google/protobuf/compiler/plugin.cc', 'google/protobuf/compiler/php/php_generator.cc', 'google/protobuf/compiler/objectivec/objectivec_primitive_field.cc', 'google/protobuf/compiler/objectivec/objectivec_oneof.cc', 'google/protobuf/compiler/objectivec/objectivec_message_field.cc', 'google/protobuf/compiler/objectivec/objectivec_message.cc', 'google/protobuf/compiler/objectivec/objectivec_map_field.cc', 'google/protobuf/compiler/objectivec/objectivec_helpers.cc', 'google/protobuf/compiler/objectivec/objectivec_generator.cc', 'google/protobuf/compiler/objectivec/objectivec_file.cc', 'google/protobuf/compiler/objectivec/objectivec_field.cc', 'google/protobuf/compiler/objectivec/objectivec_extension.cc', 'google/protobuf/compiler/objectivec/objectivec_enum_field.cc', 'google/protobuf/compiler/objectivec/objectivec_enum.cc', 'google/protobuf/compiler/js/well_known_types_embed.cc', 'google/protobuf/compiler/js/js_generator.cc', 'google/protobuf/compiler/javanano/javanano_primitive_field.cc', 'google/protobuf/compiler/javanano/javanano_message_field.cc', 'google/protobuf/compiler/javanano/javanano_message.cc', 'google/protobuf/compiler/javanano/javanano_map_field.cc', 'google/protobuf/compiler/javanano/javanano_helpers.cc', 'google/protobuf/compiler/javanano/javanano_generator.cc', 'google/protobuf/compiler/javanano/javanano_file.cc', 'google/protobuf/compiler/javanano/javanano_field.cc', 'google/protobuf/compiler/javanano/javanano_extension.cc', 'google/protobuf/compiler/javanano/javanano_enum_field.cc', 'google/protobuf/compiler/javanano/javanano_enum.cc', 'google/protobuf/compiler/java/java_string_field_lite.cc', 'google/protobuf/compiler/java/java_string_field.cc', 'google/protobuf/compiler/java/java_shared_code_generator.cc', 'google/protobuf/compiler/java/java_service.cc', 'google/protobuf/compiler/java/java_primitive_field_lite.cc', 'google/protobuf/compiler/java/java_primitive_field.cc', 'google/protobuf/compiler/java/java_name_resolver.cc', 'google/protobuf/compiler/java/java_message_lite.cc', 'google/protobuf/compiler/java/java_message_field_lite.cc', 'google/protobuf/compiler/java/java_message_field.cc', 'google/protobuf/compiler/java/java_message_builder_lite.cc', 'google/protobuf/compiler/java/java_message_builder.cc', 'google/protobuf/compiler/java/java_message.cc', 'google/protobuf/compiler/java/java_map_field_lite.cc', 'google/protobuf/compiler/java/java_map_field.cc', 'google/protobuf/compiler/java/java_lazy_message_field_lite.cc', 'google/protobuf/compiler/java/java_lazy_message_field.cc', 'google/protobuf/compiler/java/java_helpers.cc', 'google/protobuf/compiler/java/java_generator_factory.cc', 'google/protobuf/compiler/java/java_generator.cc', 'google/protobuf/compiler/java/java_file.cc', 'google/protobuf/compiler/java/java_field.cc', 'google/protobuf/compiler/java/java_extension_lite.cc', 'google/protobuf/compiler/java/java_extension.cc', 'google/protobuf/compiler/java/java_enum_lite.cc', 'google/protobuf/compiler/java/java_enum_field_lite.cc', 'google/protobuf/compiler/java/java_enum_field.cc', 'google/protobuf/compiler/java/java_enum.cc', 'google/protobuf/compiler/java/java_doc_comment.cc', 'google/protobuf/compiler/java/java_context.cc', 'google/protobuf/compiler/csharp/csharp_wrapper_field.cc', 'google/protobuf/compiler/csharp/csharp_source_generator_base.cc', 'google/protobuf/compiler/csharp/csharp_repeated_primitive_field.cc', 'google/protobuf/compiler/csharp/csharp_repeated_message_field.cc', 'google/protobuf/compiler/csharp/csharp_repeated_enum_field.cc', 'google/protobuf/compiler/csharp/csharp_reflection_class.cc', 'google/protobuf/compiler/csharp/csharp_primitive_field.cc', 'google/protobuf/compiler/csharp/csharp_message_field.cc', 'google/protobuf/compiler/csharp/csharp_message.cc', 'google/protobuf/compiler/csharp/csharp_map_field.cc', 'google/protobuf/compiler/csharp/csharp_helpers.cc', 'google/protobuf/compiler/csharp/csharp_generator.cc', 'google/protobuf/compiler/csharp/csharp_field_base.cc', 'google/protobuf/compiler/csharp/csharp_enum_field.cc', 'google/protobuf/compiler/csharp/csharp_enum.cc', 'google/protobuf/compiler/csharp/csharp_doc_comment.cc', 'google/protobuf/compiler/cpp/cpp_string_field.cc', 'google/protobuf/compiler/cpp/cpp_service.cc', 'google/protobuf/compiler/cpp/cpp_primitive_field.cc', 'google/protobuf/compiler/cpp/cpp_padding_optimizer.cc', 'google/protobuf/compiler/cpp/cpp_message_field.cc', 'google/protobuf/compiler/cpp/cpp_message.cc', 'google/protobuf/compiler/cpp/cpp_map_field.cc', 'google/protobuf/compiler/cpp/cpp_helpers.cc', 'google/protobuf/compiler/cpp/cpp_generator.cc', 'google/protobuf/compiler/cpp/cpp_file.cc', 'google/protobuf/compiler/cpp/cpp_field.cc', 'google/protobuf/compiler/cpp/cpp_extension.cc', 'google/protobuf/compiler/cpp/cpp_enum_field.cc', 'google/protobuf/compiler/cpp/cpp_enum.cc', 'google/protobuf/compiler/command_line_interface.cc', 'google/protobuf/compiler/code_generator.cc', 'google/protobuf/wrappers.pb.cc', 'google/protobuf/wire_format.cc', 'google/protobuf/util/type_resolver_util.cc', 'google/protobuf/util/time_util.cc', 'google/protobuf/util/message_differencer.cc', 'google/protobuf/util/json_util.cc', 'google/protobuf/util/internal/utility.cc', 'google/protobuf/util/internal/type_info_test_helper.cc', 'google/protobuf/util/internal/type_info.cc', 'google/protobuf/util/internal/protostream_objectwriter.cc', 'google/protobuf/util/internal/protostream_objectsource.cc', 'google/protobuf/util/internal/proto_writer.cc', 'google/protobuf/util/internal/object_writer.cc', 'google/protobuf/util/internal/json_stream_parser.cc', 'google/protobuf/util/internal/json_objectwriter.cc', 'google/protobuf/util/internal/json_escaping.cc', 'google/protobuf/util/internal/field_mask_utility.cc', 'google/protobuf/util/internal/error_listener.cc', 'google/protobuf/util/internal/default_value_objectwriter.cc', 'google/protobuf/util/internal/datapiece.cc', 'google/protobuf/util/field_mask_util.cc', 'google/protobuf/util/field_comparator.cc', 'google/protobuf/util/delimited_message_util.cc', 'google/protobuf/unknown_field_set.cc', 'google/protobuf/type.pb.cc', 'google/protobuf/timestamp.pb.cc', 'google/protobuf/text_format.cc', 'google/protobuf/stubs/substitute.cc', 'google/protobuf/stubs/mathlimits.cc', 'google/protobuf/struct.pb.cc', 'google/protobuf/source_context.pb.cc', 'google/protobuf/service.cc', 'google/protobuf/reflection_ops.cc', 'google/protobuf/message.cc', 'google/protobuf/map_field.cc', 'google/protobuf/io/zero_copy_stream_impl.cc', 'google/protobuf/io/tokenizer.cc', 'google/protobuf/io/strtod.cc', 'google/protobuf/io/printer.cc', 'google/protobuf/io/gzip_stream.cc', 'google/protobuf/generated_message_table_driven.cc', 'google/protobuf/generated_message_reflection.cc', 'google/protobuf/field_mask.pb.cc', 'google/protobuf/extension_set_heavy.cc', 'google/protobuf/empty.pb.cc', 'google/protobuf/dynamic_message.cc', 'google/protobuf/duration.pb.cc', 'google/protobuf/descriptor_database.cc', 'google/protobuf/descriptor.pb.cc', 'google/protobuf/descriptor.cc', 'google/protobuf/compiler/parser.cc', 'google/protobuf/compiler/importer.cc', 'google/protobuf/api.pb.cc', 'google/protobuf/any.pb.cc', 'google/protobuf/any.cc', 'google/protobuf/wire_format_lite.cc', 'google/protobuf/stubs/time.cc', 'google/protobuf/stubs/strutil.cc', 'google/protobuf/stubs/structurally_valid.cc', 'google/protobuf/stubs/stringprintf.cc', 'google/protobuf/stubs/stringpiece.cc', 'google/protobuf/stubs/statusor.cc', 'google/protobuf/stubs/status.cc', 'google/protobuf/stubs/once.cc', 'google/protobuf/stubs/io_win32.cc', 'google/protobuf/stubs/int128.cc', 'google/protobuf/stubs/common.cc', 'google/protobuf/stubs/bytestream.cc', 'google/protobuf/stubs/atomicops_internals_x86_msvc.cc', 'google/protobuf/stubs/atomicops_internals_x86_gcc.cc', 'google/protobuf/repeated_field.cc', 'google/protobuf/message_lite.cc', 'google/protobuf/io/zero_copy_stream_impl_lite.cc', 'google/protobuf/io/zero_copy_stream.cc', 'google/protobuf/io/coded_stream.cc', 'google/protobuf/generated_message_util.cc', 'google/protobuf/generated_message_table_driven_lite.cc', 'google/protobuf/extension_set.cc', 'google/protobuf/arenastring.cc', 'google/protobuf/arena.cc', 'google/protobuf/compiler/js/embed.cc']
 PROTO_FILES=['google/protobuf/wrappers.proto', 'google/protobuf/type.proto', 'google/protobuf/timestamp.proto', 'google/protobuf/struct.proto', 'google/protobuf/source_context.proto', 'google/protobuf/field_mask.proto', 'google/protobuf/empty.proto', 'google/protobuf/duration.proto', 'google/protobuf/descriptor.proto', 'google/protobuf/compiler/plugin.proto', 'google/protobuf/api.proto', 'google/protobuf/any.proto']
 
 CC_INCLUDE='third_party/protobuf/src'
 PROTO_INCLUDE='third_party/protobuf/src'
 
-PROTOBUF_SUBMODULE_VERSION="80a37e0782d2d702d52234b62dd4b9ec74fd2c95"
+PROTOBUF_SUBMODULE_VERSION="2761122b810fe8861004ae785cc3ab39f384d342"
diff --git a/tools/distrib/python/grpcio_tools/setup.py b/tools/distrib/python/grpcio_tools/setup.py
index e0e9226211d..8d95cb5a287 100644
--- a/tools/distrib/python/grpcio_tools/setup.py
+++ b/tools/distrib/python/grpcio_tools/setup.py
@@ -209,7 +209,7 @@ setuptools.setup(
   ext_modules=extension_modules(),
   packages=setuptools.find_packages('.'),
   install_requires=[
-    'protobuf>=3.3.0',
+    'protobuf>=3.5.0.post1',
     'grpcio>={version}'.format(version=grpc_version.VERSION),
   ],
   package_data=package_data(),
diff --git a/tools/dockerfile/interoptest/grpc_interop_csharp/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_csharp/Dockerfile
index ea82476b65f..af2ab90b76e 100644
--- a/tools/dockerfile/interoptest/grpc_interop_csharp/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_csharp/Dockerfile
@@ -62,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #================
 # C# dependencies
diff --git a/tools/dockerfile/interoptest/grpc_interop_csharpcoreclr/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_csharpcoreclr/Dockerfile
index ea82476b65f..af2ab90b76e 100644
--- a/tools/dockerfile/interoptest/grpc_interop_csharpcoreclr/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_csharpcoreclr/Dockerfile
@@ -62,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #================
 # C# dependencies
diff --git a/tools/dockerfile/interoptest/grpc_interop_cxx/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_cxx/Dockerfile
index 38d377ce2fd..ec5338b4fc3 100644
--- a/tools/dockerfile/interoptest/grpc_interop_cxx/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_cxx/Dockerfile
@@ -62,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/interoptest/grpc_interop_go/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_go/Dockerfile
index 73c41a48386..a775961ff75 100644
--- a/tools/dockerfile/interoptest/grpc_interop_go/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_go/Dockerfile
@@ -30,7 +30,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 # Define the default command.
 CMD ["bash"]
diff --git a/tools/dockerfile/interoptest/grpc_interop_go1.7/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_go1.7/Dockerfile
index 7c083de3653..c296c8c674b 100644
--- a/tools/dockerfile/interoptest/grpc_interop_go1.7/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_go1.7/Dockerfile
@@ -30,7 +30,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 # Define the default command.
 CMD ["bash"]
diff --git a/tools/dockerfile/interoptest/grpc_interop_go1.8/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_go1.8/Dockerfile
index 61efc18df92..9ac0b973415 100644
--- a/tools/dockerfile/interoptest/grpc_interop_go1.8/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_go1.8/Dockerfile
@@ -30,7 +30,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 # Define the default command.
 CMD ["bash"]
diff --git a/tools/dockerfile/interoptest/grpc_interop_http2/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_http2/Dockerfile
index 278b09a6663..92a2faa605c 100644
--- a/tools/dockerfile/interoptest/grpc_interop_http2/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_http2/Dockerfile
@@ -30,7 +30,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 RUN pip install twisted h2==2.6.1 hyper
 
diff --git a/tools/dockerfile/interoptest/grpc_interop_java/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_java/Dockerfile
index d56632440fe..34b4e39df44 100644
--- a/tools/dockerfile/interoptest/grpc_interop_java/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_java/Dockerfile
@@ -45,7 +45,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 
 # Trigger download of as many Gradle artifacts as possible.
diff --git a/tools/dockerfile/interoptest/grpc_interop_java_oracle8/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_java_oracle8/Dockerfile
index d56632440fe..34b4e39df44 100644
--- a/tools/dockerfile/interoptest/grpc_interop_java_oracle8/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_java_oracle8/Dockerfile
@@ -45,7 +45,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 
 # Trigger download of as many Gradle artifacts as possible.
diff --git a/tools/dockerfile/interoptest/grpc_interop_node/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_node/Dockerfile
index f4c3e4103e3..17671a384ed 100644
--- a/tools/dockerfile/interoptest/grpc_interop_node/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_node/Dockerfile
@@ -62,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #==================
 # Node dependencies
diff --git a/tools/dockerfile/interoptest/grpc_interop_python/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_python/Dockerfile
index d165307031d..07f419f8801 100644
--- a/tools/dockerfile/interoptest/grpc_interop_python/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_python/Dockerfile
@@ -62,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 # Prepare ccache
 RUN ln -s /usr/bin/ccache /usr/local/bin/gcc
diff --git a/tools/dockerfile/interoptest/grpc_interop_ruby/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_ruby/Dockerfile
index 2217b10b8b1..543e207c64e 100644
--- a/tools/dockerfile/interoptest/grpc_interop_ruby/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_ruby/Dockerfile
@@ -62,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #==================
 # Ruby dependencies
diff --git a/tools/dockerfile/test/csharp_jessie_x64/Dockerfile b/tools/dockerfile/test/csharp_jessie_x64/Dockerfile
index 3e31e67f5f3..0fae21de638 100644
--- a/tools/dockerfile/test/csharp_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/csharp_jessie_x64/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #================
 # C# dependencies
diff --git a/tools/dockerfile/test/cxx_alpine_x64/Dockerfile b/tools/dockerfile/test/cxx_alpine_x64/Dockerfile
index af5e7d6f14f..13a0ea10025 100644
--- a/tools/dockerfile/test/cxx_alpine_x64/Dockerfile
+++ b/tools/dockerfile/test/cxx_alpine_x64/Dockerfile
@@ -38,7 +38,7 @@ RUN apk update && apk add \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0
 
 # Google Cloud platform API libraries
 RUN pip install --upgrade google-api-python-client
diff --git a/tools/dockerfile/test/cxx_jessie_x64/Dockerfile b/tools/dockerfile/test/cxx_jessie_x64/Dockerfile
index 3492dd72c54..dff4c96e9a5 100644
--- a/tools/dockerfile/test/cxx_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/cxx_jessie_x64/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/cxx_jessie_x86/Dockerfile b/tools/dockerfile/test/cxx_jessie_x86/Dockerfile
index f8cbf35d393..ea1d6456284 100644
--- a/tools/dockerfile/test/cxx_jessie_x86/Dockerfile
+++ b/tools/dockerfile/test/cxx_jessie_x86/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/cxx_ubuntu1404_x64/Dockerfile b/tools/dockerfile/test/cxx_ubuntu1404_x64/Dockerfile
index 6966d6b8d37..990dac9128f 100644
--- a/tools/dockerfile/test/cxx_ubuntu1404_x64/Dockerfile
+++ b/tools/dockerfile/test/cxx_ubuntu1404_x64/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile b/tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile
index 016034aa50e..c8943cada98 100644
--- a/tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile
+++ b/tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/fuzzer/Dockerfile b/tools/dockerfile/test/fuzzer/Dockerfile
index 50104ad7ae7..52666eab992 100644
--- a/tools/dockerfile/test/fuzzer/Dockerfile
+++ b/tools/dockerfile/test/fuzzer/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/multilang_jessie_x64/Dockerfile b/tools/dockerfile/test/multilang_jessie_x64/Dockerfile
index 8e29fcb88c8..362c061f6df 100644
--- a/tools/dockerfile/test/multilang_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/multilang_jessie_x64/Dockerfile
@@ -141,7 +141,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 # Install coverage for Python test coverage reporting
 RUN pip install coverage
diff --git a/tools/dockerfile/test/node_jessie_x64/Dockerfile b/tools/dockerfile/test/node_jessie_x64/Dockerfile
index d0e5af64cc1..9f19e76bf51 100644
--- a/tools/dockerfile/test/node_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/node_jessie_x64/Dockerfile
@@ -77,7 +77,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #==================
 # Node dependencies
diff --git a/tools/dockerfile/test/php7_jessie_x64/Dockerfile b/tools/dockerfile/test/php7_jessie_x64/Dockerfile
index 1399502840f..865bf695fe7 100644
--- a/tools/dockerfile/test/php7_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/php7_jessie_x64/Dockerfile
@@ -77,7 +77,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 # Prepare ccache
 RUN ln -s /usr/bin/ccache /usr/local/bin/gcc
diff --git a/tools/dockerfile/test/php_jessie_x64/Dockerfile b/tools/dockerfile/test/php_jessie_x64/Dockerfile
index 56dc6045e15..fb653d365a8 100644
--- a/tools/dockerfile/test/php_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/php_jessie_x64/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #=================
 # PHP dependencies
diff --git a/tools/dockerfile/test/python_alpine_x64/Dockerfile b/tools/dockerfile/test/python_alpine_x64/Dockerfile
index 7584ab8767a..87acef9cb62 100644
--- a/tools/dockerfile/test/python_alpine_x64/Dockerfile
+++ b/tools/dockerfile/test/python_alpine_x64/Dockerfile
@@ -38,7 +38,7 @@ RUN apk update && apk add \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0
 
 # Google Cloud platform API libraries
 RUN pip install --upgrade google-api-python-client
diff --git a/tools/dockerfile/test/python_jessie_x64/Dockerfile b/tools/dockerfile/test/python_jessie_x64/Dockerfile
index 8d89f5022f2..914e3433735 100644
--- a/tools/dockerfile/test/python_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/python_jessie_x64/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 # Prepare ccache
 RUN ln -s /usr/bin/ccache /usr/local/bin/gcc
diff --git a/tools/dockerfile/test/python_pyenv_x64/Dockerfile b/tools/dockerfile/test/python_pyenv_x64/Dockerfile
index f8cbdc5726e..379f26ad911 100644
--- a/tools/dockerfile/test/python_pyenv_x64/Dockerfile
+++ b/tools/dockerfile/test/python_pyenv_x64/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 # Install dependencies for pyenv
 RUN apt-get update && apt-get install -y \
diff --git a/tools/dockerfile/test/ruby_jessie_x64/Dockerfile b/tools/dockerfile/test/ruby_jessie_x64/Dockerfile
index 5d7f80bf889..63e42fd2da4 100644
--- a/tools/dockerfile/test/ruby_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/ruby_jessie_x64/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #==================
 # Ruby dependencies
diff --git a/tools/dockerfile/test/sanity/Dockerfile b/tools/dockerfile/test/sanity/Dockerfile
index 967e813b85f..e4a2972c0e2 100644
--- a/tools/dockerfile/test/sanity/Dockerfile
+++ b/tools/dockerfile/test/sanity/Dockerfile
@@ -66,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install --upgrade pip==9.0.1
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.5.0.post1 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/interop_matrix/README.md b/tools/interop_matrix/README.md
index 588afe4fd46..40c02a1bc7a 100644
--- a/tools/interop_matrix/README.md
+++ b/tools/interop_matrix/README.md
@@ -8,8 +8,8 @@ from specific releases/tag, are used to test version compatiblity between gRPC r
 ## Step-by-step instructions for adding a GCR image for a new release for compatibility test
 We have continuous nightly test setup to test gRPC backward compatibility between old clients and latest server.  When a gRPC developer creates a new gRPC release, s/he is also responsible to add the just-released gRPC client to the nightly test.  The steps are:
 - Add (or update) an entry in `./client_matrix.py` file to reference the github tag for the release.
-- Build new client docker image(s).  For example, for java release `v1.9.9`, do
-  - `tools/interop_matrix/create_matrix_images.py --git_checkout --release=v1.9.9 --language=java`
+- Build new client docker image(s).  For example, for C and wrapper languages release `v1.9.9`, do
+  - `tools/interop_matrix/create_matrix_images.py --git_checkout --release=v1.9.9 --language cxx csharp python ruby php`
 - Verify that the new docker image was built successfully and uploaded to GCR.  For example,
   - `gcloud beta container images list --repository gcr.io/grpc-testing` shows image repos.
   - `gcloud beta container images list-tags gcr.io/grpc-testing/grpc_interop_java_oracle8` should show an image entry with tag `v1.9.9`.
diff --git a/tools/interop_matrix/client_matrix.py b/tools/interop_matrix/client_matrix.py
index c8dbb3ae666..ee24ae7b28b 100644
--- a/tools/interop_matrix/client_matrix.py
+++ b/tools/interop_matrix/client_matrix.py
@@ -19,6 +19,7 @@ def get_github_repo(lang):
   return {
       'go': 'git@github.com:grpc/grpc-go.git',
       'java': 'git@github.com:grpc/grpc-java.git',
+      'node': 'git@github.com:grpc/grpc-node.git',
       # all other languages use the grpc.git repo.
   }.get(lang, 'git@github.com:grpc/grpc.git')
 
@@ -44,6 +45,7 @@ LANG_RELEASE_MATRIX = {
         'v1.3.9',
         'v1.4.2',
         'v1.6.6',
+        'v1.7.2',
     ],
     'go': [
         'v1.0.5',
@@ -53,6 +55,10 @@ LANG_RELEASE_MATRIX = {
         'v1.5.2',
         'v1.6.0',
         'v1.7.0',
+        'v1.7.1',
+        'v1.7.2',
+        'v1.7.3',
+        'v1.8.0',
     ],
     'java': [
         'v1.0.3',
@@ -63,6 +69,7 @@ LANG_RELEASE_MATRIX = {
         'v1.5.0',
         'v1.6.1',
         'v1.7.0',
+        'v1.8.0',
     ],
     'python': [
         'v1.0.x',
@@ -72,6 +79,24 @@ LANG_RELEASE_MATRIX = {
         'v1.4.2',
         'v1.6.6',
     ],
+    'python': [
+        'v1.0.x', 
+        'v1.1.4',
+        'v1.2.5',
+        'v1.3.9',
+        'v1.4.2',
+        'v1.6.6',
+        'v1.7.2',    
+    ],
+    'python': [
+        'v1.0.x',
+        'v1.1.4',
+        'v1.2.5',
+        'v1.3.9',
+        'v1.4.2',
+        'v1.6.6',
+        'v1.7.2',    
+    ],
     'node': [
         'v1.0.1',
         'v1.1.4',
@@ -79,6 +104,7 @@ LANG_RELEASE_MATRIX = {
         'v1.3.9',
         'v1.4.2',
         'v1.6.6',
+        #'v1.7.1',  Failing tests.
     ],
     'ruby': [
         # Ruby v1.0.x doesn't have the fix #8914, therefore not supported.
@@ -87,6 +113,7 @@ LANG_RELEASE_MATRIX = {
         'v1.3.9',
         'v1.4.2',
         'v1.6.6',
+        'v1.7.2',
     ],
     'php': [
         'v1.0.1',
@@ -95,6 +122,7 @@ LANG_RELEASE_MATRIX = {
         'v1.3.9',
         'v1.4.2',
         'v1.6.6',
+        'v1.7.2',
     ],
    'csharp': [
         #'v1.0.1',
@@ -103,5 +131,6 @@ LANG_RELEASE_MATRIX = {
         'v1.3.9',
         'v1.4.2',
         'v1.6.6',
+        'v1.7.2',
     ],
 }
diff --git a/tools/interop_matrix/create_matrix_images.py b/tools/interop_matrix/create_matrix_images.py
index 21040eadf25..493a7d53647 100755
--- a/tools/interop_matrix/create_matrix_images.py
+++ b/tools/interop_matrix/create_matrix_images.py
@@ -77,6 +77,15 @@ argp.add_argument('--keep',
                   action='store_true',
                   help='keep the created local images after uploading to GCR')
 
+argp.add_argument('--reuse_git_root',
+                  default=False,
+                  action='store_const',
+                  const=True,                  
+                  help='reuse the repo dir. If False, the existing git root '
+                  'directory will removed before a clean checkout, because '
+                  'reusing the repo can cause git checkout error if you switch '
+                  'between releases.')
+
 
 args = argp.parse_args()
 
@@ -133,7 +142,7 @@ def build_image_jobspec(runtime, env, gcr_tag, stack_base):
   }
   build_env.update(env)
   build_job = jobset.JobSpec(
-          cmdline=[os.path.join(stack_base, _IMAGE_BUILDER)],
+          cmdline=[_IMAGE_BUILDER],
           environ=build_env,
           shortname='build_docker_%s' % runtime,
           timeout_seconds=30*60)
@@ -227,6 +236,11 @@ def checkout_grpc_stack(lang, release):
   repo_dir = os.path.splitext(os.path.basename(repo))[0]
   stack_base = os.path.join(args.git_checkout_root, repo_dir)
 
+  # Clean up leftover repo dir if necessary.
+  if not args.reuse_git_root and os.path.exists(stack_base):
+    jobset.message('START', 'Removing git checkout root.', do_newline=True)
+    shutil.rmtree(stack_base)
+
   if not os.path.exists(stack_base):
     subprocess.check_call(['git', 'clone', '--recursive', repo],
                           cwd=os.path.dirname(stack_base))
diff --git a/tools/interop_matrix/testcases/node__v1.0.1 b/tools/interop_matrix/testcases/node__v1.0.1
index fca98215442..6faf3213917 100644
--- a/tools/interop_matrix/testcases/node__v1.0.1
+++ b/tools/interop_matrix/testcases/node__v1.0.1
@@ -1,21 +1,21 @@
 #!/bin/bash
 echo "Testing ${docker_image:=grpc_interop_node:a53aa5e3-b548-4566-b5a8-6d15c1315b32}"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_00c688f2-57da-4023-89f3-46b1f7b5869f $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test.sandbox.googleapis.com --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=large_unary"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_d86705d8-14ea-4024-90b6-de74d6e8d19c $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test.sandbox.googleapis.com --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=empty_unary"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_ebaafacd-1d82-4a75-bea1-a5c64e01fcaf $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test.sandbox.googleapis.com --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=ping_pong"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_5125241a-fbf6-4c1c-895b-026a5a41f02f $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test.sandbox.googleapis.com --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=empty_stream"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_3d5e5b82-7205-4eba-b775-8122f05a4760 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test.sandbox.googleapis.com --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=client_streaming"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_16fa0b49-2083-4932-8f26-79cfdffec940 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test.sandbox.googleapis.com --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=server_streaming"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_23cee670-2d8d-4f5c-8893-c3c43da8b03a $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test.sandbox.googleapis.com --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=cancel_after_begin"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_7b6a9454-e3b6-4993-b542-468e268930aa $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test.sandbox.googleapis.com --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=cancel_after_first_response"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_5a7109ed-c065-4b62-98f4-b3ed8f385762 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test.sandbox.googleapis.com --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=timeout_on_sleeping_server"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_1e0ba8dd-4dc1-431b-b202-529e7ace5d1d $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test4.sandbox.googleapis.com --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=large_unary"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_649de56a-e722-4a59-b265-e9c0e871f068 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test4.sandbox.googleapis.com --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=empty_unary"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_8be512a2-5e1c-4858-8cfc-82f99b678b76 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test4.sandbox.googleapis.com --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=ping_pong"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_d19b6333-e528-48b5-8421-2ae3f7ce9dab $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test4.sandbox.googleapis.com --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=empty_stream"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_4749c80a-21c5-4d81-9df5-3c46ba6480cd $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test4.sandbox.googleapis.com --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=client_streaming"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_b7bee545-4857-4269-a1f2-9553dfc7e4b8 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test4.sandbox.googleapis.com --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=server_streaming"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_4e96db87-6f48-426d-a7f0-97f3a5b6b3f4 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test4.sandbox.googleapis.com --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=cancel_after_begin"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_31a1d58c-f8bf-460a-af60-28969ecaaf80 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test4.sandbox.googleapis.com --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=cancel_after_first_response"
-docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_ce64b147-bcfa-44b2-a2f7-4a485380ce30 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=grpc-test4.sandbox.googleapis.com --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=timeout_on_sleeping_server"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_00c688f2-57da-4023-89f3-46b1f7b5869f $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=large_unary"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_d86705d8-14ea-4024-90b6-de74d6e8d19c $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=empty_unary"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_ebaafacd-1d82-4a75-bea1-a5c64e01fcaf $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=ping_pong"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_5125241a-fbf6-4c1c-895b-026a5a41f02f $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=empty_stream"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_3d5e5b82-7205-4eba-b775-8122f05a4760 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=client_streaming"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_16fa0b49-2083-4932-8f26-79cfdffec940 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=server_streaming"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_23cee670-2d8d-4f5c-8893-c3c43da8b03a $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=cancel_after_begin"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_7b6a9454-e3b6-4993-b542-468e268930aa $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=cancel_after_first_response"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_5a7109ed-c065-4b62-98f4-b3ed8f385762 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=timeout_on_sleeping_server"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_1e0ba8dd-4dc1-431b-b202-529e7ace5d1d $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=large_unary"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_649de56a-e722-4a59-b265-e9c0e871f068 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=empty_unary"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_8be512a2-5e1c-4858-8cfc-82f99b678b76 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=ping_pong"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_d19b6333-e528-48b5-8421-2ae3f7ce9dab $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=empty_stream"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_4749c80a-21c5-4d81-9df5-3c46ba6480cd $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=client_streaming"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_b7bee545-4857-4269-a1f2-9553dfc7e4b8 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=server_streaming"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_4e96db87-6f48-426d-a7f0-97f3a5b6b3f4 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=cancel_after_begin"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_31a1d58c-f8bf-460a-af60-28969ecaaf80 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=cancel_after_first_response"
+docker run -i --rm=true -w /var/local/git/grpc --net=host --name interop_client_node_ce64b147-bcfa-44b2-a2f7-4a485380ce30 $docker_image bash -l -c "node src/node/interop/interop_client.js --server_host=216.239.32.254 --server_host_override=grpc-test4.sandbox.googleapis.com --server_port=443 --use_tls=true --test_case=timeout_on_sleeping_server"
 
diff --git a/tools/run_tests/generated/configs.json b/tools/run_tests/generated/configs.json
index abbe76d60c2..fee8290efe0 100644
--- a/tools/run_tests/generated/configs.json
+++ b/tools/run_tests/generated/configs.json
@@ -20,7 +20,10 @@
     }
   }, 
   {
-    "config": "msan"
+    "config": "msan", 
+    "environ": {
+      "MSAN_OPTIONS": "poison_in_dtor=1"
+    }
   }, 
   {
     "config": "basicprof"
diff --git a/tools/run_tests/sanity/check_submodules.sh b/tools/run_tests/sanity/check_submodules.sh
index 1f7b078ff7a..b573d21f4fd 100755
--- a/tools/run_tests/sanity/check_submodules.sh
+++ b/tools/run_tests/sanity/check_submodules.sh
@@ -31,7 +31,7 @@ cat << EOF | awk '{ print $1 }' | sort > $want_submodules
  886e7d75368e3f4fab3f4d0d3584e4abfc557755 third_party/boringssl-with-bazel (version_for_cocoapods_7.0-857-g886e7d7)
  30dbc81fb5ffdc98ea9b14b1918bfe4e8779b26e third_party/gflags (v2.2.0)
  ec44c6c1675c25b9827aacd08c02433cccde7780 third_party/googletest (release-1.8.0)
- 80a37e0782d2d702d52234b62dd4b9ec74fd2c95 third_party/protobuf (v3.4.0)
+ 2761122b810fe8861004ae785cc3ab39f384d342 third_party/protobuf (v3.5.0)
  cacf7f1d4e3d44d871b605da3b647f07d718623f third_party/zlib (v1.2.11)
  3be1924221e1326df520f8498d704a5c4c8d0cce third_party/cares/cares (cares-1_13_0)
  73594cde8c9a52a102c4341c244c833aa61b9c06 third_party/bloaty