Technical Summary
This document describes an abstract mechanism by which senders inform
the network about the congestion encountered by packets earlier in
the same flow. Today, network elements at any layer may signal
congestion to the receiver by dropping packets or by ECN markings,
and the receiver passes this information back to the sender in
transport-layer feedback. The mechanism described here enables the
sender to also relay this congestion information back into the
network in-band at the IP layer, such that the total amount of
congestion from all elements on the path is revealed to all IP
elements along the path, where it could, for example, be used to
provide input to traffic management. This mechanism is called
congestion exposure or ConEx. The companion document "ConEx Concepts
and Use Cases" provides the entry-point to the set of ConEx
documentation.
Working Group Summary
There were no special issues worth noting during the WG process.
Document Quality
The document received several thorough reviews. It is worth noting the
reviews from Mirja Kuehlewind and David Wagner.
Personnel
Marcelo Bagnulo (marcelo@it.uc3m.es) is the document shepherd.
Martin Stiemerling (mls.ietf@gmail.com) is the responsible Area Director.