The IESG has approved the following document: - 'OSPF Protocol Extensions for Path Computation Element (PCE) Discovery ' <draft-ietf-pce-disco-proto-ospf-08.txt> as a Proposed Standard This document is the product of the Path Computation Element Working Group. The IESG contact persons are Ross Callon and David Ward. A URL of this Internet-Draft is: http://www.ietf.org/internet-drafts/draft-ietf-pce-disco-proto-ospf-08.txt Technical Summary There are various circumstances where it is highly desirable for a Path Computation Client (PCC) to be able to dynamically and automatically discover a set of Path Computation Elements (PCE), along with some information that can be used for PCE selection. When the PCE is a Label Switching Router (LSR) participating in the Interior Gateway Protocol (IGP), or even a server participating passively in the IGP, a simple and efficient way to discover PCEs consists of using IGP flooding. For that purpose, this document defines extensions to the Open Shortest Path First (OSPF) routing protocol for the advertisement of PCE Discovery information within an OSPF area or within the entire OSPF routing domain. Working Group Summary No dissent reported. The choice is relatively obvious for networks running OSPF. Of course an IS-IS version is also needed for those networks that are running IS-IS (and will be submitted to the IESG soon). Protocol Quality Ross Callon has reviewed this spec for the IESG. I will check on whether there are implementations. Note to RFC Editor Section 1: Insert two new terms in alphabetic order in the list as follows: PCED: PCE Discovery. TLV: Type-Length-Variable data encoding. Section 4.1 OLD The PCE-ADDRESS sub-TLV is mandatory; it MUST be present within the PCED TLV. It MAY appear twice, when the PCE has both an IPv4 and IPv6 address. It MUST NOT appear more than once for the same address type. If it appears more than once, only the first occurrence is processed and any others MUST be ignored. NEW The PCE-ADDRESS sub-TLV is mandatory; it MUST be present within the PCED TLV. It MAY appear twice, when the PCE has both an IPv4 and IPv6 address. It MUST NOT appear more than once for the same address type. If it appears more than once for the same address type, only the first occurrence is processed and any others MUST be ignored. Section 5, in the fourth paragraph, remove the last two sentences. Thus: OLD The PCE address (i.e., the address indicated within the PCE ADDRESS sub-TLV) SHOULD be reachable via some prefixes advertised by OSPF. This allows the detection of a PCE failure to be sped up. When the PCE address is no longer reachable, the PCE node has failed, has been torn down, or there is no longer IP connectivity to the PCE node. NEW The PCE address (i.e., the address indicated within the PCE ADDRESS sub-TLV) SHOULD be reachable via some prefixes advertised by OSPF. Insert immediately after this paragraph: The PCED TLV information regarding a specific PCE is only considered current and useable when the router advertising this information is itself reachable via OSPF calculated paths in the same area of the LSA in which the PCED TLV appears. A change in the state of a PCE (activate, deactivate, parameter change) MUST result in a corresponding change in the PCED TLV information advertised by an OSPF router (inserted, removed, updated) in its LSA. The way PCEs determine the information they advertise and how that information is made available to OSPF is out of the scope of this document. Some information may be configured (e.g., address, preferences, scope) and other information may be automatically determined by the PCE (e.g. areas of visibility). Delete the last paragraph of section 5 (this paragraph begins "The way PCEs determine...", and has been moved up in the text). Replace all of section 9.3 with the following text: 9.3. Liveness Detection and Monitoring This document specifies the use of OSPF as a PCE Discovery Protocol. The requirements specified in RFC 4674 include the ability to determine liveness of the PCE Discovery protocol. Normal operation of the OSPF protocol meets these requirements. Section 10 OLD We would also like to thank Dave Ward, Lars Eggert, Sam Hartman, and Tim Polk for their comments during the final stages of publication. NEW We would also like to thank Dave Ward, Lars Eggert, Sam Hartman, Tim Polk, and Lisa Dusseault for their comments during the final stages of publication. _______________________________________________ IETF-Announce@ietf.org https://www1.ietf.org/mailman/listinfo/ietf-announce
