<!--
If you know who should review your pull request, please assign it to that
person, otherwise the pull request would get assigned randomly.
If your pull request is for a specific language, please add the appropriate
lang label.
-->
Closes#36333
COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/36333 from yijiem:bump_dev_version_202404101721 0a7cc5b4b7
PiperOrigin-RevId: 623878150
Change was created by the release automation script. See go/grpc-release.
Closes#35899
COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35899 from eugeneo:bump_dev_version_202402131133 73950425c9
PiperOrigin-RevId: 606777850
Change was created by the release automation script. See go/grpc-release.
Closes#35580
COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35580 from stanley-cheung:bump_dev_version_202401171835 b363888ca5
PiperOrigin-RevId: 599267642
<!--
If you know who should review your pull request, please assign it to
that
person, otherwise the pull request would get assigned randomly.
If your pull request is for a specific language, please add the
appropriate
lang label.
-->
This adds a new channel argument `GRPC_ARG_DSCP` which allows users to
create classified gRPC streams with a
Differentiated Services Code Point (DSCP) marking on the IP frames.
The channel argument is handled on both clients and servers, but
currently only on posix based systems.
Fixes#17225
**Background**:
In addition to what is already described is #17225, when gRPC is used in
telco systems there is often a need to classify streams of importance.
There can be multiple hops between two endpoints (e.g. between 2 telecom
operators) and some streams that are more important than others (e.g.
emergency call related or similar). By marking the IP packets using DSCP
the aware routers can make a sound decision of the prioritization.
This PR propose to use DSCP as the configuration value since its common
for both IPv4/IPv6, an alternative would be to use a config name that
includes TOS and Traffic Class.
There might be more needed regarding documentation and end2end testing,
but there I need some advice.
**References**
https://datatracker.ietf.org/doc/html/rfc2474https://www.iana.org/assignments/dscp-registry/dscp-registry.xhtml
<!--
Your pull request will be routed to the following person by default for
triaging.
If you know who should review your pull request, please remove the
mentioning below.
-->
@yashykt