Generic Interface List; Lfa Over Pseudowire Headend; Pw-He Multicast; Pw-He Over Mpls-Te Tunnels - Cisco ASR 9000 Series Configuration Manuallines

Generic Interface List

Generic Interface List
A generic interface list contains is a list of physical or bundle interfaces that is used in a PW-HE connection.
The generic interface list supports only main interfaces, and not sub-interfaces. The generic interface list is
bi-directional and restricts both receive and transmit interfaces on access-facing line cards. The generic
interface list has no impact on the core-facing side.
A generic interface list is used to limit the resources allocated for a PWHE interface to the set of interfaces
specified in the list.
Only the S-PE is aware of the generic interface list and expects that the PWHE packets arrive on only line
cards with generic interface list members on it. If packets arrive at the line card without generic interface list
members on it, they are dropped.

LFA over Pseudowire Headend

From Release 5.1.1, PW-HE is supported on loop free alternate (LFA) routes.
For LFA to be effective on a PW-HE interface, all the routing paths (protected and backup) must be included
in the generic interface list of that PW-HE interface. If all the routing paths are not included in the generic
interface list, then there may be loss of traffic even if LFA is enabled. This is because the LFA route could
be the one that was not included in the generic interface list.
To configure LFA on PW-HE interface, do the following:
1. Configuring Generic Interface List
2. Configuring IP/LDP Fast Reroute
For more information about configuring the IP Fast Reroute Loop-free alternate, see Implementing IS-IS on
Cisco IOS XR Software module of the Cisco ASR 9000 Series Aggregation Services Router Routing
Configuration Guide.

PW-HE Multicast

Multicast support for Pseudowire Head-end (PW-HE) interfaces is available only on the enhanced ethernet
cards.
For more information about PW-HE multicast feature, see the Implementing Layer 3 Multicast Routing chapter
in the Cisco ASR 9000 Series Aggregation Services Router Multicast Configuration Guide, Release 5.1.x.

PW-HE over MPLS-TE Tunnels

The PW-HE over MPLS-TE Tunnels feature supports forwarding of pseudowire traffic (with pseudowire
headend) over TE tunnels.
For more information about PW-HE over MPLS TE Tunnels, see the Implementing MPLS Traffic Engineering
chapter in the Cisco ASR 9000 Series Aggregation Services Router MPLS Configuration Guide, Release 5.1.x.

L2VPN over GRE

To transport an IP packet over a generic routing encapsulation (GRE) tunnel, the system first encapsulates
the original IP packet with a GRE header. The encapsulated GRE packet is encapsulated once again by an
outer transport header that is used to forward the packet to it's destination. The following figure captures how
GRE encapsulation over an IP transport network takes place.
L2VPN and Ethernet Services Configuration Guide for Cisco ASR 9000 Series Routers, IOS XR Release 6.3.x
224
Implementing Multipoint Layer 2 Services