Path Computation Element (pce)

WG Name Path Computation Element
Acronym pce
Area Routing Area (rtg)
State Active
Charter charter-ietf-pce-07 Approved
Status update Show Changed 2021-07-22
Document dependencies
Additional resources GitHub
Wiki, Zulip stream
Personnel Chairs Dhruv Dhody, Julien Meuric
Area Director John Scudder
Secretary Andrew Stone
Delegates Andrew Stone, John Scudder
Liaison Contacts Andrew Stone, Dhruv Dhody, Julien Meuric
Liaison CC Contact John Scudder
Mailing list Address pce@ietf.org
To subscribe https://www.ietf.org/mailman/listinfo/pce
Archive https://mailarchive.ietf.org/arch/browse/pce/
Chat Room address https://zulip.ietf.org/#narrow/stream/pce

Charter for Working Group

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 not be physically located on each head-end LSR. The TEAS
Working Group is responsible for defining and extending architectures
for Traffic Engineering (TE) and it is expected that the PCE and TEAS
WGs will work closely together on elements of TE architectures that
utilize PCE.

The PCE WG works on the 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 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
protocols specified in the CCAMP and TEAS WGs.

Work Items:

  • PCEP extensions to support MPLS and GMPLS Traffic Engineered LSP
    path computation models involving PCEs. 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 the TEAS Working Group, development of PCE-
    based architectures for Traffic Engineering.

  • 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 expressing path computation
    requests and responses in the various GMPLS-controlled networks,
    including WSON.

  • Definition of PCEP extensions for path computation in multi-layer
    networks.

  • 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 receiving
    PCC/PCE chooses to not follow the recommendation.

Milestones

Date Milestone Associated documents
Feb 2015 Evaluate WG progress, recharter or close

Done milestones

Date Milestone Associated documents
Done Submit the stateful PCE document(s) to the IESG
Done Submit the PCEP MIB to the IESG to be considered as a Proposed Standard
Done Submit extensions for hierarchical model to the IESG to be considered as a Proposed Standard
Done Submit inter-layer extensions to the IESG to be considered as a Proposed Standard
Done Submit PCEP extensions for GMPLS to the IESG to be considered as a Proposed Standard
Done Submit inter-area/AS applicability statement to the IESG as an informational RFC
Done Submit the GMPLS requirements to the IESG to be considered as an Informational RFC
Done Submit applicability and metrics documents to the IESG
Done Submit PCE P2MP PCEP protocol extensions to the IESG to be considered as an Proposed Standard RFC
Done Submit PCE P2MP communication requirements to the IESG to be considered as an Informational RFC
Done Submit first draft of the PCE P2MP PCEP protocol extensions
Done Submit first draft of the PCE P2MP communication requirements
Done Submit PCE communication protocol specification to the IESG to be considered as a Proposed Standard
Done Submit PCE communication protocol requirements to the IESG to be considered as an Informational RFC
Done Submit PCE discovery protocol extensions specifications to the IESG to be considered as a Proposed Standard
Done Submit first draft of the MIB module for the PCE protocol
Done Submit PCE architecture specification to the IESG to be considered as Informational RFC
Done Submit first draft of the PCE communication protocol specification
Done Submit first draft of the definition of objective metrics
Done Submit first draft of the PCE communication protocol requirements
Done Submit first draft of PCE architecture document
Done Submit first draft of PCE discovery requirements and protocol extensions documents