Why did we decide to update this book on ATM once again? Mainly, because the publisher asked us to! Seriously, though, in the fast moving telecommunications industry, a lot has happened since the publication of the last edition in 1998. In case you have been asleep, Internet-based communication is clearly the killer application for networking. Much effort is being expended for it to support an ever-broader range of communications applications in a more cost-effective manner. During the early part of the Internet growth spurt in the mid-1990s, ATM was an essential technology employed by Internet service providers to provide higher-speed switching than the routers of that time could support. However, since ATM was not designed specifically to support IP, and was actually somewhat inefficient in doing so, there arose a strong motivation to take the best parts of ATM and put them into a protocol specifically designed to provide a high performance, cost effective infrastructure for IP. The result of that effort has become known as Multiprotocol Label Switching (MPLS). This is the reason that this acronym now shares the title of this edition with ATM.
ATM (Asynchronous Transfer Mode) and MPLS (Multiprotocol Label Switching) are both standards for transferring information over networks. This is a complete guide to understanding and implementing these networking technologies.
