{"draft":"draft-ietf-teas-pcecc-use-cases-18","doc_id":"RFC9689","title":"Use Cases for a PCE as a Central Controller (PCECC)","authors":["Z. Li","D. Dhody","Q. Zhao","Z. Ke","B. Khasanov"],"format":["HTML","TEXT","PDF","XML"],"page_count":"37","pub_status":"INFORMATIONAL","status":"INFORMATIONAL","source":"Traffic Engineering Architecture and Signaling","abstract":"The PCE is a core component of a Software-Defined Networking (SDN)\r\nsystem. It can be used to compute optimal paths for network traffic\r\nand update existing paths to reflect changes in the network or\r\ntraffic demands. The PCE was developed to derive Traffic Engineering\r\n(TE) paths in MPLS networks, which are supplied to the headend of the\r\npaths using the Path Computation Element Communication Protocol\r\n(PCEP).\r\n\r\nSDN has much broader applicability than signalled MPLS TE networks,\r\nand the PCE may be used to determine paths in a range of use cases\r\nincluding static Label-Switched Paths (LSPs), Segment Routing (SR),\r\nService Function Chaining (SFC), and most forms of a routed or\r\nswitched network. Therefore, it is reasonable to consider PCEP as a\r\ncontrol protocol for use in these environments to allow the PCE to be\r\nfully enabled as a central controller.\r\n\r\nA PCE as a Central Controller (PCECC) can simplify the processing of\r\na distributed control plane by blending it with elements of SDN\r\nwithout necessarily completely replacing it. This document describes\r\ngeneral considerations for PCECC deployment and examines its\r\napplicability and benefits, as well as its challenges and\r\nlimitations, through a number of use cases.  PCEP extensions, which\r\nare required for the PCECC use cases, are covered in separate\r\ndocuments.","pub_date":"December 2024","keywords":["SDN"],"obsoletes":[],"obsoleted_by":[],"updates":[],"updated_by":[],"see_also":[],"doi":"10.17487\/RFC9689","errata_url":null}