VPN Service Profile-Based Provisioning

Chapter 1 About Cisco IP Solution Center

Overview of ISC

•Route Distinguisher (RD) pool: The IP subnets advertised by the CE routers to the PE routers are augmented with a 64-bit prefix called a route distinguisher (RD) to make them unique. The resulting 96-bit addresses are then exchanged between the PEs, using a special address family of Multiprotocol BGP (referred to as MP-BGP). The RD pool is a pool of 64-bit RD values that ISC uses to make sure the IP addresses in the network are unique.

•Site of origin pool: The pool of values for the site-of-origin attribute. The site-of-origin attribute prevents routing loops when a site is multihomed to the MPLS VPN backbone. This is achieved by identifying the site from which the route was learned, based on its SOO value, so that it is not readvertised back to that site from a PE in the MPLS VPN network.

All these resources, that are made available to the service provider, enable the automation of service deployment.

Features and Functions Provided in Provisioning with ISC

ISC assumes that the iBGPv4 core over MPLS, IGP, and VPNv4 neighbors are preprovisioned.

The features and functions provided in provisioning MPLS VPNs are as follows:

•ISC configures the IP addresses on the CE and PE interfaces.

IP addresses are assumed to be specified by the service provider and unique in the network.

•Configures CE and PE routing.

This allocates the PE VRF, route target, and route distinguisher values

•Advertises CE site routes to other sites in the same VPN.

•Supports unmanaged CEs

•Allows service request removal and modification

•Support for MP-BGPv4 commands

–BGP transparent: PE to CE routing protocol metric preserved between VPN sites.

–Neighbor AS override: You can reuse the same autonomous system number between VPN sites.

–AS-allow: Allows an autonomous system number multiple times in the AS path.

•Supports VRF commands:

–import map

–export map

–maximum routes in a VRF

•Management VPN support

•Provisioning of CE Loopback interfaces

For all MPLS VPN provisioning, several network elements that participate in the VPN must be defined. These parameters are:

•Choice of protocols between PE-CE and their intrinsic characteristics.

•IP addressing for each site joining the IP VPN

Cisco IP Solution Center, 3.0: MPLS VPN Management User Guide, 3.0

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