Hi all: I have performed an Operations Directorate review of draft-ietf-isis-te-metric-extensions-09 "In certain networks, such as, but not limited to, financial information networks (e.g. stock market data providers), network performance criteria (e.g. latency) are becoming as critical to data path selection as other metrics. This document describes extensions to IS-IS Traffic Engineering Extensions (RFC5305) such that network performance information can be distributed and collected in a scalable fashion. The information distributed using IS-IS TE Metric Extensions can then be used to make path selection decisions based on network performance. Note that this document only covers the mechanisms with which network performance information is distributed. The mechanisms for measuring network performance or acting on that information, once distributed, are outside the scope of this document." Overall, this draft does what its abstract says, i.e. defines sub-TLVs that can be used in a specified set of IS-IS TLVs. These sub-TLVs will be the initial entries in a new IANA Registry, 'IS-IS TE Metric Extensions'. I have one issue to raise: the last paragraph of section 2 (introducing the metrics to for each of the new sub-TLVs) says that the values "MUST be calculated as rolling averages where the averaging period MUST be a configurable period of time." This draft does not say how that interval will be configured. For proper operation, surely all participating IS-IS routers will need to use the same measurement interval? I suggest that some text explaining this, and saying how a router's measurement interval can be checked by other routers, would be useful. Apart from that issue, the draft is ready to publish. Cheers, Nevil -- --------------------------------------------------------------------- Nevil Brownlee Computer Science Department Phone: +64 9 373 7599 x88941 The University of Auckland FAX: +64 9 373 7453 Private Bag 92019, Auckland 1142, New Zealand