A new IETF working group has been proposed in the Routing Area. The IESG has not made any determination as yet. The following description was submitted, and is provided for informational purposes only. Please send your comments to the IESG mailing list (iesg@ietf.org) by December 30th. +++ Path Computation Element (pce) ================================ Current Status: Proposed Working Group Description of Working Group: The PCE Working Group is chartered to specify a Path Computation Element (PCE) based architecture for the computation of paths for MPLS and GMPLS Traffic Engineering LSPs. In this architecture path computation does not occur on the head-end (ingress) LSR, but on some other path computation entity that may physically not be located on the head-end LSR. The PCE WG will work on application of this model within a single domain or within a small group of domains (where a domain is a layer, IGP area or Autonomous System with limited visibility from the head-end LSR). At this time, applying this model to large groups of domains such as the Internet is not thought to be possible, and the PCE WG will not spend energy on that topic. The WG will specify a protocol for communication between LSRs (termed Path Computation Clients - PCCs) and PCEs, and between cooperating PCEs. This protocol will be capable of representing requests for path computation including a full set of constraints, will be able to return multiple paths, and will include security mechanisms such as authentication and confidentiality. The WG will determine requirements for extensions to existing routing and signaling protocols in support of PCE discovery and signaling of inter-domain paths. Candidate protocols for extensions are RSVP-TE, OSPF-TE, ISIS-TE and BGP. Any necessary extensions will be produced in collaboration with the Working Groups responsible for the protocols. The Working Group will also work on the definition of metrics to evaluate path quality, scalability, responsiveness and robustness of path computation models. Work Items: - Functional specification of MPLS and GMPLS Traffic Engineered LSP path computation models involving Path Computation Element(s). This includes the case of computing the paths of intra and inter-domain TE LSPs. Such path computation includes the generation of primary, protection and recovery paths, as well as computations for (local/global) reoptimization and load balancing. The WG will address the inter-area (single IGP domain) scenario first. WG progress will be evaluated before inter-AS related work is started. - Specification of the PCE-based architecture. - Specification of requirements and protocol extensions related to the policy, and security aspects of PCE-based path computation involving PCEs of multiple administrative entities. - In cooperation with protocol specific Working Group (OSPF, ISIS, IDR, MPLS, CCAMP), development of routing (OSPF, ISIS, BGP) and LSP signaling (RSVP-TE) extensions required to support PCE-based path computation models. - Specification of techniques in support of PCE discovery within and across domains. Where such techniques result in the extensions of existing protocols (OSPF, ISIS and BGP), this work will be done in conjunction with the appropriate WGs. - Specification of a new communication protocol for use between a PCC and a PCE, and between PCEs. A single protocol will be selected from among candidates that include the existing protocols defined in other WGs. - Definition of objective metrics to evaluate various criteria such as the measurement of path quality, response time, robustness and scalability of path computation models. Review of the document "Requirements for path computation element in GMPLS inter-domain networks" produced by the CCAMP WG. _______________________________________________ IETF-Announce@ietf.org https://www1.ietf.org/mailman/listinfo/ietf-announce
