- What Is MPLS?
- Why Is MPLS Needed?
- How Is MPLS Done?
- When and Where Is MPLS Used?
- Who Is Doing MPLS?
- The Label Switching Paradigm
- A Quick Introduction to MPLS
- Evolution of Internet Network Models
- Basics of the Internet
- Internetworking Technology Basics
- More Basics: Graph Theory and Modeling Language
- The Promise of MPLS
- The Promise of the Promise of MPLS
This chapter introduced MPLS by presenting the "five W's and H" of MPLS.
What is MPLS? MPLS is a set of open, standards-based Internet technologies that combines Layer 3 routing with Layer 2 switching to forward packets by utilizing short, fixed-length labels. A more narrow definition of MPLS is that it is an IETF working group and its associated efforts.
Why is MPLS needed? MPLS is not so much a performance gain to conventional routing, but rather it provides an innovative approach by offering a virtual connection-type label switching technology that will enable a new set of Internet applications for providing TE, QoS, path restoral, and VPNs.
How is MPLS done? MPLS complements IP technology by using a label swapping, data forwarding paradigm and introducing a new set of MPLS control procedures that are partially based on existing IP routing protocols with extensions.
When is MPLS used? MPLS is used when Internet applications such as TE, QoS, path restoral, and VPNs need to be deployed. Service providers have begun deploying MPLS to more fully utilize their networks.
Where is MPLS used? Initial MPLS deployments have moved from test labs and university test sites into the core of several large service providers. MPLS is also beginning to be deployed in metropolitan areas for a variety of application scenarios. The opportunity to derive revenue from providing provider-based VPNs is a current driver for deploying MPLS.
Who is doing MPLS? In addition to service providers, initial MPLS developers, users, and investigators include many large network equipment vendors, test equipment makers, larger service providers, and communication stack providers.
Since MPLS is an Internet technology, this chapter also introduced the Internet and several of its main models. Background topics such as graph theory and the UML modeling language were also exposed. Finally, the promise of MPLS was introduced for consideration throughout the book on how the flexibility and simplification offered by MPLS will be realized.