1 / 10

Multi-hop Pseudowire Setup and Maintenance using LDP draft-balus-mh-pw-control-protocol-00.txt

Multi-hop Pseudowire Setup and Maintenance using LDP draft-balus-mh-pw-control-protocol-00.txt. David McDysan, MCI Florin Balus, Nortel. Challenges LDP Session Scaling PSN Tunnel Scaling PSN Interoperability Control Interoperability Authentication Discovery TE & QoS Support.

morna
Télécharger la présentation

Multi-hop Pseudowire Setup and Maintenance using LDP draft-balus-mh-pw-control-protocol-00.txt

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Multi-hop Pseudowire Setup and Maintenance using LDPdraft-balus-mh-pw-control-protocol-00.txt David McDysan, MCI Florin Balus, Nortel

  2. Challenges • LDP Session Scaling • PSN Tunnel Scaling • PSN Interoperability • Control Interoperability • Authentication • Discovery • TE & QoS Support • Solutions • Switching PE (S-PE) • Limit Meshes to Hierarchical Level • Convert/Authenticate at Hierarchical Boundaries • BGP+ Distribution • RADIUS+ Discovery & Authentication • RSVP-TE+ & PW-LDP+ U-PE U-PE U-PE U-PE S-PE S-PE S-PE S-PE U-PE U-PE U-PE U-PE U-PE U-PE U-PE U-PE MH PW Challenges & Solutions Inter-provider Use Case Service Provider 1 Service Provider 2 Metro Access Interconnection Use Case Backbone Metro Access 2 Metro Access 1

  3. MH PW Requirements Addressed • Dynamic creation of MH PW using IP addressing • Encoding supports other address types (e.g., NSAP) • Automatic determination of intermediate S-PEs based upon IP routing • S-PE_hop-by-S-PE_hop routing • Minimal OSS “touches” at only U-PE(s) • Supports single (or double) sided provisioning • Supports OAM capability negotiation • Operational consistency with SH PW

  4. Solution Space • draft-martini-pwe3-pw-switching • LDP based solution • Provides generic solutions for different PSN types • Provides solutions when signaling separation is required • draft-balus-mh-pw-control • LDP based , complementary solution with draft-martini-pwe3-pw-switching • Extends solution when signaling separation is not required to provide: • Dynamic MH-PW setup and maintenance • Single or Double sided end to end provisioning

  5. MH PW Requirements Not (Yet) Addressed • Quantity and Quality of Service signaling, admission control • MH PW Resiliency • Do we need specific procedures for handling explicit routing of intermediate S-PE in LDP? • Need to agree/complete requirements • E.g., is there a need for option to traverse same set of S-PEs in each direction?

  6. Operational Consistency – Service ManagementPWID Example Pseudo-Wires Setup and Maintenance • Defined in draft-ietf-pwe3-control-protocol Multi-Hop Pseudo-Wires Setup and Maintenance • Defined in draft-balus-mh-pw-control-00.txt • End to end service entity • Same Service Identification with regular PWs • Supports both PWID and Generalized ID FECs PW U-PE1, PWID=40, U-PE2 (U-)PE1 (U-)PE2 P (LSR) LDP Session Virtual Forwarder S-PE2 S-PE3 MH PW U-PE1, PWID=40, U-PE2

  7. MH-PW Setup & Maintenance - Provisioning Models • 1b. U-PE2 is provisioned with • PWID = 40 • Remote PE IP = U-PE1 • 1. U-PE1 is provisioned with • PWID = 40 • Remote PE IP = U-PE2 Same Provisioning procedures, options: e.g. double, single sided provisioning PW 40 40 U-PE1 S-PE1 S-PE2 U-PE2 P AC11 AC21 40 40 MH PW • 1. U-PE1 is provisioned with • PWID = 40 • Remote PE IP = U-PE2 • 1b. U-PE2 is provisioned with • PWID = 40 • Remote PE IP =U-PE1

  8. MH PW TLV • Addresses the requirement for dynamic signaling of the MH PW • Identifies the LDP message as a multi-hop PW • Enables consistent usage of PWID FEC • Source U-PE Field - Identifies the originating U-PE. • U-PE Peer Discovery or Verification • Destination U-PE field - Identifies the remote U-PE • Controls propagation of the signaling messages • Provisioned or Auto-discovered New PW Signaling Element – MH PW TLV LDP Label Mapping Message PWid & GID FEC TLV Label TLV Other Optional TLVs • MH PW TLV • Source U-PE • Destination U-PE New TLV • TLV inserted by the originating U-PE • Prefix Format (L3FEC) proposed for all internal fields

  9. 4. On receipt of the LM: use destination U-PE to find the next signaling hop. 22. 30. 3. U-PE1 builds LM & forwards to S-PE1 5. S-PE1 builds new LM & forwards to U-PE2 6. On receipt of the LM: check Destination U-PE = itself. Verify Source Address against provisioned Destination U-PE. PW FEC TLV 40 PW FEC TLV 40 Label TLV Label TLV 30 22 Source U-PE Source U-PE U-PE1 U-PE1 MH PW TLV Destination U-PE Destination U-PE U-PE2 U-PE2 MH PWs using End to End LDP Signaling – Operational WalkthroughHighlighting only the Steps Specific to MH PW • 1. Provisioning on U-PE1 • PWID = 40 • Remote PE = U-PE2 • 1b. Provisioning on U-PE2 • PWID = 40 • Remote PE = U-PE1 2. Use destination U-PE to find the next signaling hop. LDP LDP U-PE2 U-PE1 S-PE1 P P

  10. Next Steps • Agree where the MH PW Signaling Formats and Procedures should be performed: PWE3/L2VPN? • i.e. “how do I connect the endpoints/virtual forwarders?” • What about the Discovery of the “MH PW Topology”? • i.e. “what needs to be connected”?… • Complete items not yet addressed

More Related