Overview

General information

Service providers require a solution for interconnecting customer sites that span different domains, such as MAN-WAN or Inter-AS (in the same Service Provider or Inter-Provider). The NFM-P supports two methods for interconnecting customers sites:

• PW routing

• MS-PW routing

PW routing

The NFM-P supports inter-domain services for VLL through the use of VLL spoke switching, which allows creation of a VLL service by cross-connecting two spoke SDPs. However, this requires statically configuring the PW switching points at the gateway S-PEs between domains. See VLL spoke switching in Chapter 76, VLL service management for more information.

Static PW routing is supported on the 7210 SAS, 7450 ESS, 7750 SR, and 7950 XRS. Support for 7210 SAS NEs varies depending on the chassis type and release; see the NE documentation for information.

MS-PW routing

Multi-segment pseudowire routing provides solutions for inter-domain services by using dynamic MS-PW routing and signaling, in which the switching points are automatically instantiated in the Switching-Provider Edge (S-PE) NEs. The path of the MS-PW is dynamically signaled end-to-end by T-LDP, using PW routing information stored in the S-PEs by MP-BGP. Per-PW configuration is only required at the endpoints of the MS-PW in the Termination-Provider Edge (T-PE) NEs.

Dynamic MS-PWs are characterized by the following:

• They are supported for VLL Epipe services

• Dynamic and static routes, as well as explicit paths for MS-PWs are supported

• Dynamic MS-PWs may be established across LDP or RFC 3107 labeled BGP SDPs

• Dynamic MS-PWs may be used as a part of a set of PWs for PW redundancy, including MC-LAG. Diverse routes for the active and standby MS-PWs can be configured by using explicit paths, or dynamically by using a BGP route distinguisher.

• Diverse routes for the active and standby MS-PWs can be achieved by using explicit paths or dynamically using a BGP route distinguisher.

Dynamic MS-PWs are supported on the following NEs:

• 7210 SAS

• 7450 ESS and 7750 SR chassis types that support Epipe service creation

• 7950 XRS

Support for 7210 SAS NEs varies depending on the chassis type and release; see the NE documentation for information.

Dynamic MS-PW services

Spoke SDP FEC configuration will bind a service to an existing Service Distribution Point (SDP), using a dynamic MS-PW. When using dynamic MS-PWs, the particular SDP to bind to is automatically selected based on the Target Attachment Individual Identifier (TAII) and the path to use, specified under the Spoke SDP FEC. The selected SDP will terminate on the first hop S-PE of the MS-PW. Therefore, an SDP should be defined that can reach the first hop of the MS-PW. The NE creates a spoke SDP binding to associate an SDP with a service. If the required SDP does not exist, the NE creates one based on the parameters specified in the spoke SDP FEC, for example, the SAII/TAII, Path, or PW template. The Creation Mode attribute for such an SDP indicates Multi-Segment PW.

This differs from the regular spoke SDP binding creation in that it creates a spoke SDP binding using a PW with the FEC128. However, the Spoke SDP FEC enables PWs with other FEC types to be used.

Spoke SDP FEC configuration is currently only applicable to an Epipe site. It can be configured under the Epipe service or at a service endpoint of an Epipe site, with or without ICB. The creation under an Epipe service is demonstrated in To configure a dynamic MS-PW service using PW routing .