Summary

This chapter is by no means an exhaustive discussion of MPLS. There are entire library shelves dedicated to the topic. However, it does give an overview of what goes on in an MPLS network, especially the use and distribution of labels and how to use them to build TE tunnels and VPNs.

Note that a big advantage of MPLS is the interoperability with IP services, as shown here with quality of service. The EXP bits allow the same QoS policies to be applied to MPLS packets as are applied to IP packets. Chapter 5 looks at how VPN services are offered on broadband interfaces.