Internet Core Protocols: The Definitive Guide

Foreword

The Internet began as a research effort to link different kinds of packet-switched networks in such a way that the computers that were attached to each of the packet networks did not need to know anything about the nature of or the existence of any networks other than the ones to which the host was directly connected. What emerged was a layered design that used encapsulation to carry end-to-end “Internet” packets from the source host, through intermediate networks and gateways to the destination host. The first Internet incorporated three wide/medium area networks including the ARPAnet, the Atlantic Packet Satellite net (SATNET), and a ground mobile Packet Radio network (PRNET). Eventually it also included the first 3 MB/s Ethernet developed at Xerox PARC in 1973.

Now, some twenty-five years after the first designs, there are hundreds of thousands of networks comprising the Internet, serving an estimated 45 million computers and 150 million users. Moreover, the original speeds of the trunking circuits in the constituent networks have increased from thousands of bits per second to billions of bits per second, with trillions of bits per second lurking in laboratory demonstrations. As the Internet has grown, its complexity and the number of people dependent on it have both increased substantially. But the number of people with detailed understanding of the protocols and systems that allow the Internet to work represent a declining fraction of the total population of users or ...