If you've ever been responsible for a network, you know that sinkingfeeling: your pager has gone off at 2 a.m., the network is broken, and you can't figure out why by using a dial-in connection from home. You drive into the office, dig out your protocol analyzer, and spend the next four hours trying to put things back together before the staff shows up for work. When this happens, you often find yourself looking at the low-level guts of the Internet protocols: you're deciphering individual packets, trying to figure out what is (or isn't) happening. Until now, the only real guide to the protocols has been the Internet RFCs--and they're hardly what you want to be reading late at night when your network is down. There hasn't been a good book on the fundamentals of IP networking aimed at network administrators--until now. Internet Core Protocols: The Definitive Guide contains all the information you need for low-level network debugging. It provides thorough coverage of the fundamental protocols in the TCP/IP suite: IP, TCP, UDP, ICMP, ARP (in its many variations), and IGMP. (The companion volume, Internet Application Protocols: The Definitive Guide, provides detailed information about the commonly used application protocols, including HTTP, FTP, DNS, POP3, and many others). It includes many packet captures, showing you what to look for and how to interpret all the fields. It has been brought up to date with the latest developments in real-world IP networking. The CD-ROM included with the book contains Shomiti's "Surveyor Lite," a packet analyzer that runs on Win32 systems, plus the original RFCs, should you need them for reference. Together, this package includes everything you need to troubleshoot your network--except coffee.

For network administrators, support professionals, and system designers, intimate knowledge of the network protocols that are the foundation of the Internet is crucial. Internet Core Protocols: The Definitive Guide is a superb summary of the nitty-gritty details of the most important Net standards.

This book assumes you have a working knowledge of networks and a basic familiarity with TCP/IP. Unlike the cursory coverage of TCP/IP found in many Internet titles, this presentation includes low-level details that aid in troubleshooting. It also includes a copy of Shomiti Surveyor Lite--a utility for analyzing network traffic. Extensive screen shots of Surveyor Lite also illustrate data fields.

Each protocol is examined closely, using network diagrams and detailed breakdowns of the fields and flags. In addition to TCP, IP and UDP, there is far-reaching discussion of multicasting and error communication protocols, including practical application issues such as caching and timeouts to provide a real-world perspective.

In addition to an education into the particulars of the Net's underpinnings, this book is an excellent reference tool. --Stephen W. Plain

Topics covered: TCP/IP overview, Internet Protocol (IP), Address Resolution Protocol (ARP), Multicasting, Internet Group Management Protocol (IGMP), Internet Control Message Protocol (ICMP), User Datagram Protocol (UDP), and Transmission Control Protocol (TCP).