Layer 2 Wholesale Network Topology Overview
This configuration explains how to configure a simple Layer 2 wholesale subscriber access network. This solution illustrates two Internet Service Provider (ISP) retailers sharing access to a wholesaler network. The wholesaler network contains a Layer 2 Network access router and two Virtual Private LAN Service (VPLS) network-to-network interface (NNI) routers.
You can have more than one ISP router connecting to a single VPLS NNI router with VPLS interfaces configured with routing instances specific to each different ISP-facing interfaces.
The example also shows two different connection options from one subscriber access router to one of the individual ISP access routers. One connection option uses an interface on the subscriber access router to connect directly to the ISP access router. Another connection option uses two routers: a subscriber access router and another NNI router that connects to the ISP access router.
When using the NNI router connection option, use a standard BGP or MPLS configuration between the subscriber access routers and the edge router that connects to the ISP access routers. See the BGP User Guide for information about BGP configuration. See the MPLS Applications User Guide for information about MPLS configuration.
Figure 1 provides the reference topology for this configuration example.
