Use of pseudowire template for BGP VPWS

The pseudowire template concept used for BGP AD is reused for BGP VPWS to dynamically instantiate pseudowires (SDP-bindings) and the related SDPs (provisioned or automatically instantiated).

The settings for the L2-Info extended community in the BGP update sent by the system are derived from the pw-template attributes. The following rules apply:

On reception, the values of the parameters in the L2-Info extended community of the BGP update are compared with the settings from the corresponding pw-template. The following steps are used to determine the local pw-template:

The following pseudowire template parameters are supported when applied within a BGP VPWS service; the remainder are ignored:

configure service pw-template policy-id [use-provisioned-sdp | 
       [prefer-provisioned-sdp] [auto-sdp]] [create] [name name]
   accounting-policy acct-policy-id 
   no accounting-policy
   [no] collect-stats
   [no] controlword
   egress 
      filter ipv6 ipv6-filter-id 
      filter ip ip-filter-id
      filter mac mac-filter-id
      no filter [ip ip-filter-id] [mac mac-filter-id] [ipv6 ipv6-filter-id]
      qos network-policy-id port-redirect-group queue-group-name instance instance
id
      no qos [network-policy-id] 
   [no] force-vlan-vc-forwarding
   hash-label [signal-capability] 
   no hash-label
   ingress 
      filter ipv6 ipv6-filter-id 
      filter ip ip-filter-id
      filter mac mac-filter-id
      no filter [ip ip-filter-id] [mac mac-filter-id] [ipv6 ipv6-filter-id]
      qos network-policy-id fp-redirect-group queue-group-name instance instance-id 
      no qos [network-policy-id]
   [no] sdp-exclude
   [no] sdp-include
   vc-type {ether | vlan}
   vlan-vc-tag vlan-id
   no vlan-vc-tag 

For more information about this command, see the 7450 ESS, 7750 SR, 7950 XRS, and VSR Services Overview Guide.

The use-provisioned-sdp option is permitted when creating the pseudowire template if a preprovisioned SDP is to be used. Preprovisioned SDPs must be configured whenever RSVP-signaled transport tunnels are used.

When the prefer-provisioned-sdp option is specified, if the system finds an existing matching SDP that conforms to any restrictions defined in the pseudowire template (for example, sdp-include or sdp-exclude group), it uses this matching SDP (even if the existing SDP is operationally down); otherwise, it automatically creates an SDP.

When the auto-gre-sdp option is specified, a GRE SDP is automatically created.

The tools perform command can be used in the same way as for BGP-AD to apply changes to the pseudowire template using the following format:

tools perform service [id service-id] eval-pw-template policy-id [allow-service-impact]

If a user configures a service using a pseudowire template with the prefer-provisioned-sdp option, but without provisioning an applicable SDP and the system binds to an automatic SDP, and the user subsequently provisions an appropriate SDP, the system does not automatically switch to the new provisioned SDP. This only occurs if the pseudowire template is reevaluated using the tools perform service id service-id eval-pw-template command.