MPLS multi-VRF design and implementation using GNS simulator

MPLS(Multi Protocol Label Switching) is an emerging technology [1] which has started attracting all the service provider networks with its exceptional and admirable features. VPN(Virtual Private Network) is one of its most popular feature which carries traffic securely and privately from customer's one end to another through the service provider's network. However, in this case the CE(Customer Edge) router is not involved in providing private network through the customary LAN. The Multi-VRF(Virtual Routing and Forwarding) CE feature-also known as VRF-Lite-is a feature whereby the VPN functionality is extended to the CE router in an economical way. A Multi-VRF router can run multiple instances of routing protocols with a neighboring router with overlapping address spaces configured on different VRF instances. Hence, only one CE router is needed for multiple VPNs, thus simplifying provisioning and network management rather than a multiple CE router solution. This paper describes the designing of such a Multi-VRF MPLS network on the service provider's end which can separate a customer's large network into smaller sites and keep them isolated in a cost-effective way. GNS(Graphical Network Simulator) software stack with VMware virtualization were chosen for this purpose, as these applications are well suited for emulation of real network environment. The resultant network obtained after this design is a real time solution to many problems and demands in today's service provider's network.