Baseline Encoding and Transport of Pre-Congestion Information, November 2009
- Canonical URL:
- File formats:
- PROPOSED STANDARD
- Obsoleted by:
- RFC 6660
- T. Moncaster
- pcn (tsv)
The objective of the Pre-Congestion Notification (PCN) architecture is to protect the quality of service (QoS) of inelastic flows within a Diffserv domain. It achieves this by marking packets belonging to PCN-flows when the rate of traffic exceeds certain configured thresholds on links in the domain. These marks can then be evaluated to determine how close the domain is to being congested. This document specifies how such marks are encoded into the IP header by redefining the Explicit Congestion Notification (ECN) codepoints within such domains. The baseline encoding described here provides only two PCN encoding states: Not-marked and PCN-marked. Future extensions to this encoding may be needed in order to provide more than one level of marking severity. [STANDARDS-TRACK]
For the definition of Status, see RFC 2026.
For the definition of Stream, see RFC 4844.