July 23, 2007 Eiji Oki (NTT) Adrian Farrel (Old Dog Consulting)

1. Extensions to the Path Computation Element Communication Protocol (PCEP) for Route Exclusionsdraft-oki-pce-pcep-xro-01.txt July 23, 2007 Eiji Oki (NTT) Adrian Farrel (Old Dog Consulting)

2. Summary of this draft • This draft was adopted as WG doc after Prague meeting. • This draft defines protocol extensions. • Allow PCC to specify route exclusions to PCE on path computation request. • PCECP generic requirements [RFC4657] includes route exclusions. • Reminder... • Not part of base PCEP specification • Trying to let that stabilise on core function

3. Summary of this draft (Cont’d) • Modeled on RFC4874 • Exclude Route List • New PCEP object defined as the Exclude Route Object (XRO). • Explicit Route Exclusions • Existing Include Route Object (IRO) in PCEP modified by introducing • New IRO subobject, • Explicit Exclusion Route Subobject (EXRS)

4. Changes from 00 • Section 2.1.1 • F bit is defined in XRO. • Moved from main PCEP specification • Used to request a replacement path of a failed LSP • Section 2.1.2 • Cases of XRO present in a PCRep message are described. • Section 3 • Exclude Route with Confidentiality is added, which is used for inter-domain diverse path computation to preserve confidentiality. • Leverages Path Key work (next slide)

5. Inter-domain diverse path computation • Secondary path computation • PCReq message MAY carry XRO with Path Key ID to avoid the primary path route to preserve confidentiality. Newly defined XRO with Path Key ID PCReq PCE ERO with Path Key ID PCE PCRep A C Ingress Egress ERO with Path Key ID D B

6. Next step… • An experimental implementation already exists. • We appreciate your feedback.