BGP/MPLS VPNs

摘要

This document describes a method by which a Service Provider with anIP backbone may provide VPNs (Virtual Private Networks) for itscustomers. MPLS (Multiprotocol Label Switching) is used forforwarding packets over the backbone, and BGP (Border GatewayProtocol) is used for distributing routes over the backbone. Theprimary goal of this method is to support the outsourcing of IPbackbone services for enterprise networks. It does so in a mannerwhich is simple for the enterprise, while still scalable and flexiblefor the Service Provider, and while allowing the Service Provider toadd value. These techniques can also be used to provide a VPN whichitself provides IP service to customers.