Last Call Review of draft-ietf-ippm-multipoint-alt-mark-06
review-ietf-ippm-multipoint-alt-mark-06-genart-lc-dunbar-2020-03-05-00

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Document: draft-ietf-ippm-multipoint-alt-mark-06
Reviewer: Linda Dunbar
Review Date: 2020-03-05
IETF LC End Date: 2020-03-06
IESG Telechat date: 2020-03-12

Summary:
This document is to expand P2P flows marking methodology to measure unicast
flows in  multipoint-to-multipoint network. The mechanism is quite interesting.
However, I do have some questions:

Page 9 (Section 5: Multipoint Packet Loss): Second paragraph stating that "the
sum of the number of packets on all ingress interfaces equals the number on the
egress interfaces for the monitored flow".

how to measure? with all nodes having different timer, it would be difficult to
quantify the time period. At any given time T, egress node may count packets
entered at T-x. Where to draw the line? packets may traverse different routes
through the network, and can take different time.

Section 6.1 Algorithm for Cluster Partition:
How do you partition the cluster if the Application ingress the network via
different nodes?

Major issues: None
Minor issues: None

Nits/editorial comments:

Page 5: first sentence on the policies to classify flows: should allow
additional conditions that are not in the packet header as part of matching
criteria

Thank you very much.

Linda Dunbar