SDP subtypes of the MPLS type are available to allow service binding to an SR tunnel programmed in TTM by OSPF or IS-IS:
*A:7950 XRS-20# configure service sdp 100 mpls create
*A:7950 XRS-20>config>service>sdp$ sr-ospf
*A:7950 XRS-20>config>service>sdp$ sr-isis
The SDP of type sr-isis or sr-ospf can be used with the far-end option. When the sr-isis or sr-ospf value is enabled, a tunnel to the far-end address is selected in the TTM from the lowest preference IS-IS or OSPF instance. If many instances have the same lowest preference from the lowest numbered IS-IS or OSPF instance. The SR-ISIS or SR-OSPF tunnel is selected at the time of the binding, following the tunnel selection rules. If a more preferred tunnel is subsequently added to the TTM, the SDP does not automatically switch to the new tunnel until the next time the SDP is being re-resolved.
The tunnel-far-end option is not supported. In addition, the mixed-lsp-mode option does not support the sr-isis and sr-ospf tunnel types.
The signaling protocol for the service labels for an SDP using an SR tunnel can be configured to static (off), T-LDP (tldp), or BGP (bgp).
SR tunnels can be used in VPRN and BGP EVPN with the auto-bind-tunnel command. See Next-Hop Resolution for more information.
Both VPN-IPv4 and VPN-IPv6 (6VPE) are supported in a VPRN or BGP EVPN service using segment routing transport tunnels with the auto-bind-tunnel command.
See BGP and the 7450 ESS, 7750 SR, 7950 XRS, and VSR Layer 3 Services Guide: IES and VPRN for more information about the VPRN auto-bind-tunnel CLI command.