Path Computation Element

The information below is for an older approved charter
Document Charter Path Computation Element WG (pce) Snapshot
Title Path Computation Element
Last updated 2013-05-17
State Approved
WG State Active
IESG Responsible AD Deborah Brungard
Charter Edit AD Adrian Farrel
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The PCE Working Group is chartered to specify the required protocols so
  as to enable a Path Computation Element (PCE)-based architecture for the
  computation of paths for MPLS and GMPLS Point to Point and Point to
  Multi-point Traffic Engineered LSPs.

  In this architecture path computation does not necessarily occur on the
  head-end (ingress) LSR, but on some other path computation entity that
  may physically not be located on each head-end LSR.
  The PCE WG works on application of this model within a single domain
  or within a 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 specifies the PCE communication Protocol (PCEP) and needed
  extensions for communication between LSRs (termed Path Computation
  Clients - PCCs) and PCEs, and between cooperating PCEs. Security
  mechanisms such as authentication and confidentiality are included.
  The WG determines requirements for extensions to existing routing and
  signaling protocols in support of the PCE architecture and the signaling
  of inter-domain paths (e.g. RSVP-TE and its GMPLS variations). Any
  necessary extensions will be produced in collaboration with the Working
  Groups responsible for the protocols.
  The WG also works on the mechanisms to for multi-layer path computation
  and PCEP extensions for communication between several network layers.
  The WG defines the required PCEP extensions for Wavelength Switched
  Optical Networks (WSON) while keeping consistency with the GMPLS
  architecture specified in the CCAMP WG.

Work Items:
  - PCEP extensions for MPLS and GMPLS Traffic Engineered LSP path
    computation models involving PCE(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. Both intra- and inter-domain
    applications are covered.
  - In cooperation with protocol specific Working Group (e.g., MPLS,
    CCAMP), development of LSP signaling (RSVP-TE) extensions required
    to support PCE-based path computation models.
  - Specification of PCEP extensions for communication in the various
    GMPLS-controlled networks, including WSON.
  - Definition of PCEP extensions for path computation in multi-layer
  - Definition of the PCEP extensions used by a stateful PCE for 
    recommending a new path for an existing or new LSP to the PCC/PCE.
    Further protocol extensions must cover the case where the 
    recommendation is not followed by the PCC/PCE.