This document specifies two packet metering and marking
behaviours of PCN nodes. These metering and marking
behaviours are implemented in PCN interior nodes to signal
the onset of pre-congestion to PCN boundary nodes.
Threshold-metering and -marking marks all PCN-packets if
the PCN traffic rate is greater than a configured rate
("PCN-threshold-rate"). Excess-metering and -marking marks
a proportion of PCN-packets, such that the amount marked
equals the traffic rate in excess of a configured rate
("PCN-excess-rate"). The level of PCN marking allows PCN
boundary nodes to determine the extent of pre-congestion on
ingress-egress paths, which is used to make PCN traffic
admission or termination decisions.
Working Group Summary
The document was subject to thorough review by the PCN working
group, and strong consensus for publication was reached.
The document shepherd was Steven Blake (email@example.com).
Lars Eggert (firstname.lastname@example.org) reviewed the document for