Multi Protocol Label Switching (MPLS) On Cisco IOS | An Introduction

If traffic wants to get from one host to another host and that traffic has to be routed, every router along the path must know about the destination. If the a router does not know about the final destination, the router will drop the traffic.

Multi-Protocol Label Switching (MPLS) is a technology used most commonly in Internet Service Provider (ISP) environments to get around this problem. Instead of every router knowing about the final destination, they only need to know how to get traffic to a router who knows the final destination. So a router in the transit path between two BGP routers isn't required to also run BGP and learn the full BGP table.

This tutorial will explain how MPLS can be used to tunnel traffic over a network so every router along the path doesn't need to know about the final destination.