BGP Connector Attribute IETF 64 Nov 2005

Tunneling applications in BGP Various Tunneling applications exist or are being proposed in BGP Some examples are : The MDT SAFI used for Auto-discovery of MDTs for PIM LAN procedures in Multicast VPNs The Tunnel SAFI for Tunnel discovery

MDT discovery in PIM-LAN procedures for MVPNs The MDT SAFI carries the Tunnel endpoint address in the NLRI of the form RD:Tunnel-address, MDT-group address Needs an RPF check on the Tunnel-endpoint-address The VPNv4 update carries the VPNv4 NLRI of the form RD: IP-address a BGP Connector attribute of the form Tunnel-address The BGP Connector attribute for the VPNv4 NLRI links the NLRI carried by the MDT SAFI

Tunnel Endpoint discovery The Tunnel SAFI carries the Tunnel endpoint address in the NLRI of the form Tunnel-ID:Tunnel-address a BGP Tunnel Encapsulation attribute which contains encapsulations and preferences. The VPNv4 update carries the VPNv4 NLRI of the form RD: IP-address a BGP Connector attribute of the form Tunnel-ID:Tunnel-address The BGP Connector attribute for the VPNv4 NLRI links the Tunnel SAFI NLRI

Tunnel Discovery PE-2 CE-2 CE-2 PE-1 CE-1 PE-3 CE-3 VPNv4 update RD2:1.1.1 NHOP = PE1 Connector = TunID2:PE1 PE-2 VPNv4 update RD1:1.1.1.1 NHOP = PE1 Connector = TunID1:PE1 CE-2 Host = 2.2.2.2 CE-2 PE-1 CE-1 Host = 1.1.1.1 PE-3 VPNv4 update RD1:1.1.1 NHOP = PE1 Connector = TunID2:PE1 VPNv4 update RD1:1.1.1.1 NHOP = PE1 Connector = TunID1:PE1 CE-3

Tunnel Discovery (contd.) VPNv4 update RD1:1.1.1.1 NHOP = PE1 Connector = TunID1:PE1 VPNv4 update RD1:1.1.1.1 NHOP = ASBR-1 Connector = TunID1:PE1 PE-1 PE-2 ASBR-1 ASBR-2 VPNv4 update RD1:1.1.1.1 NHOP = ASBR-1 Connector = TunID1:PE1 CE-1 Host = 1.1.1.1 CE-3

Summary The Connector attribute is used for carrying the address of a Tunnel endpoint or an originator in a given network. Already has 3 applications. Could have more.