In an MPLS PE router, CE advertised routes are segmented from other CE routers by assigning CE-facing interfaces to different Virtual Routing and Forwarding (VRF) instances12. A VRF is a technology that allows multiple instances of a routing table to co-exist within the same router at the same time. By associating a network interface with a VRF, the network layer (Layer 3) has a different view of the network topology. This allows the segmentation of routing paths for traffic from different customers or different types of traffic. In the context of MPLS, VRFs are used to create separate routing instances for each customer on a PE router3.