Service Packet Forwarding using SR-TE LSP

An SDP sub-type of the MPLS encapsulation type allows service binding to a SR-TE LSP programmed in TTM by MPLS:

*A:7950 XRS-20# configure service sdp 100 mpls create
    — *A:7950 XRS-20>config>service>sdp$ sr-te-lsp lsp-name

The user can specify up to 16 SR-TE LSP names. The destination address of all LSPs must match that of the SDP far-end option. Service data packets are sprayed over the set of LSPs in the SDP using the same procedures as for tunnel selection in ECMP. Each SR-TE LSP can, however, have up to 32 next-hops at the ingress LER when the first segment is a node SID-based SR tunnel. Consequently, service data packet will be forwarded over one of a maximum of 16x32 next-hops. The tunnel-far-end option is not supported. In addition, the mixed-lsp-mode option does not support the sr-te tunnel type.

The signaling protocol for the service labels for an SDP using a SR-TE LSP can be configured to static (off), T-LDP (tldp), or BGP (bgp).

An SR-TE LSP can be used in VPRN auto-bind with the following commands:

config>service>vprn>
        — auto-bind-tunnel
            — resolution {any | disabled | filter}
            — resolution-filter
                — [no] sr-te
            — exit
        — exit

Both VPN-IPv4 and VPN-IPv6 (6VPE) are supported in a VPRN service using segment routing transport tunnels with the auto-bind-tunnel command.

This auto-bind-tunnel command is also supported with BGP EVPN service, as shown below:

config>service>vpls>bgp-evpn>mpls>
        — auto-bind-tunnel
            — resolution {any | disabled | filter}
            — resolution-filter
                — [no] sr-te
            — exit
        — exit

The following service contexts are supported with SR-TE LSP: