Technical Summary
The draft defines a simple extension to the QUIC transport (RFC 9000), using the
well-defined extension mechanisms. It registers a new DATAGRAM frame type for
unreliable application data and clearly describes how the frame transmission and
reception operates within the loss recovery and detection framework of QUIC.
Working Group Summary
There are two notable points but clear WG consensus was established through the
development and last call.
The first point is about datagram demultiplexing identifiers. Prior to WG
adoption of this document, earlier drafts included a demultiplexing field in the
DATAGRAM frame. Discussion of the document before adoption led to the field
being removed and the definition of such a field delegated to applications using
datagrams. The topic came up again during the WG activity and we were able to
reach clear consensus to continue delegating the field to applications. In
future, with deployment experience, we may discover patterns of identifiers that
could be incorporated into the transport layer. There was consensus to not block
progress on this draft in order to wait for such experience.
The second point is about DATAGRAM ack-elicitation. Near the time the document
was ready for WGLC, a use case was identified for delaying acknowledgement of
DATAGRAMs. There was some rigourous discussion on this topic, with several
proposals for design change to the datagram specification. In opposition of such
design changes were concerns over unintended consequences to congestion control.
WG discussion identified other ways in which the use case might be addressed,
which harnessed the extensibility mechanisms of the QUIC protocol. Given the
broad range of possible technical solutions, the chairs sought clarity about
whether the group believed the use case needed to be solved in the scope of this
document. A consensus call was issued and the responses established clear
consensus to not work it.
Document Quality
There are several implementations of the datagram extension and several
interoperable deployments of the datagram extension deployed on the Internet.
This extension provides an unreliable data transport feature that application
protocols can build upon. Within the IETF, the MASQUE and WebTrans WGs have
adopted documents to define such application uses. Other members of the
community are also interested in using this extension.
Personnel
Lucas Pardue is the document shepherd. Zaheduzzaman Sarker is the responsible area director.