ABSTRACT
This chapter describes the many methods developed to integrate IP routing with ATM switching, culminating in the development of MPLS, or Multiprotocol Label Switching. MPLS is a set of standards being developed by the Internet Engineering Task Force (IETF) to allow Layer 3 IP forwarding (traditionally performed by routers) to be combined with Layer 2 switching (such as ATM and Frame Relay) in
a single combined system, to increase the scalability, speed, and traffic engineering capabilities of the Internet. It also adds additional functionality in routers such as traffic engineering (also known as service provisioning and bandwidth management) and virtual private networks that has traditionally been found only in switches.
