1 OSPF Based L1VPN Auto-Discovery ( draft-bryskin-l1vpn-ospf-auto-discovery-00.txt ) Igor Bryskin (Movaz Networks) : Lou Berger (LabN Consulting, LLC) :

2 Purpose of the document qTo provide OSPF based L1VPN PE Auto-Discovery mechanism vAs described in Layer 1 VPN Basic Mode qParallels BGP based L1VPN auto-discovery

3 Why IGP? qBGP approach also being defined vRequires all L1VPN edge nodes to support BGP qIGP alternative vParticularly applicable in networks where L1VPN edge nodes do not run BGP vFacilitates efficient and reliable distribution of routing and application information among IGP speakers vMaintains this information network-wide synchronized in conditions when some IGP speakers go in and out of service vAllows controlling the flooding scope vBut, floods information to all IGP nodes, not just PEs qOSPF vThis draft covers OSPF only vParallel ISIS could be easily defined if there’s interest

4 Integration with Traffic Engineering qL1VPN autodiscovery mechanism based on IGP allows for integration with the Traffic Engineering vOne example: L1VPN LSAs allow for the inclusion of TE attributes (of CE-PE links) vSuch integration is NOT required by the draft

5 L1VPN LSA and its TLVs qOpaque OSPF LSA (RFC2370) of a new opaque type is introduced for carrying L1VPN specific information qL1VPN INFO TLV is introduced for encoding one entry of Port Information Table (PIT)  L1VPN PE Address TLV is introduced to facilitate validation of L1VPN INFO advertisements originated outside of the area where they are used vThis mechanism is patterned after the way ASBR information (OSPF LSAs type 4) is used to validate AS external information (OSPF LSAs type 5)

6 L1VPN LSA format | LS age | Options | LS Type | | Opaque Type | Opaque ID | | Advertising Router | | LS Sequence Number | | LS checksum | Length | | L1VPN TLV(s) | |... | | TE TLV | |... |

7 L1VPN INFO TLV format | L1VPN TLV length | L1VPN TLV Type | | L1VPN Globally unique identifier | | | | PE TE Address | |... | | L1VPN Auto-Discovery Information | |... |

8 L1VPN PE Address TLV format | L1VPN TLV length | L1VPN TLV Type | | PE TE Address |

9 Advertising rules qA PE originates AS-scope L1VPN LSAs carrying a single L1VPN INFO TLV for every locally configured PE-CE link. The LSA may also carry TE Link TLV with the link attributes qA PE originates area-scope L1VPN LSA carrying L1VPN PE Address TLV for every PE address that was advertised by the PE in L1VPN INFO TLVs qABRs summorise received area-scope L1VPN LSAs (with L1VPN PE Address TLVs) and re-originate them into adjacent areas. ABRs withdraw their advertisements if/when the originator of a received LSA becomes unreachable

10 Processing rules qA PE that receives AS-scope L1VPN LSA with L1VPN INFO TLV uses such LSA for updating its local PIT if and only if the PE can find in its LSDB L1VPN LSA with L1VPN PE Address TLV matching the address specified in the received L1VPN INFO TLV

11 Notes qThe mechanism proposed in the draft could be used not just for L1VPN autodiscovery. One example: [GVPNs] proposes using E-BGP for publishing of membership information by PEs to CEs. Such service could be realized using PE-CE IGP qIn general, whatever could be done with BGP extensions could be also done with IGP extensions qThis document cover OSPF only, vsame approach can be applied to ISIS qDo we need a generic mechanism for validation of AS-scope opaque advertisements (mesh membership, node capabilities, L1VPN, etc.)? qWe propose to make this draft a WG document

12 Thank You