This 976-page second edition of the text suggests a detailed introspection on the transmission control protocol/Internet protocol (TCP/IP) architecture, and, indeed, the content fulfills this promise.

A reference on the TCP/IP protocols and services, the text is aimed at networking students and professionals. The complete TCP/IP, although being the indispensable core of the Internet, has been covered thoroughly in surprisingly few books. There are several books by some of the original developers of the Internet that go into deep details, and these are used as textbooks in networking courses. However, few of them are continuously updated at the pace of Internet development.

The number of requests for comments (RFCs) endorsed by the Internet Engineering Task Force (IETF) increases every year. RFCs are publicly available documents that contain all the important information on the TCP/IP and Internet, including the de facto Internet standards. The author mentions that there were 2,500 RFCs at time of writing, but currently there are 3,500 RFCs in existence. Maybe this note was not updated in the second edition, but one can notice some of the newer issues missing in the recently published book.

Thirty-one chapters, nine appendices, a glossary, a list of references, and a detailed index make up the book. The first part, chapters 1 to 3, covers layering principles, comparing the TCP/IP hierarchy to the open systems interconnection (OSI) reference model, and underlying technologies (network infrastructures) that, despite not being an inherent part of the TCP/IP specification, are indispensable for better understanding of current networking.

The core of TCP/IP, which consists of the IP at the network layer, and the TCP or user datagram protocol (UDP) at the transport layer, has not changed over the years, and the importance of learning it has been growing. These core protocols are thoroughly described in chapters 4 through 12, including IP addressing. Their operation and message formats, including all types, codes, and parameters are explained in detail. Unicast and multicast routing protocols (chapters 13 through 14) are also discussed in detail, with respect to protocol characteristics. Readers will not find any details on the routing protocol implementation in the network under different circumstances.

The new version of the IP protocol (IPv6) has not yet been fully endorsed, although its wide deployment is probably very close. The book devotes the last chapter to IPv6 and the related Internet control message protocol (ICMPv6), and briefly touches on required changes in application protocols related to the change to IPv6. However, the security and mobility benefits of IPv6 are not emphasized enough. The address space extension achieved in IPv6 is primarily mentioned. Mobile IP is covered separately in one of the chapters added in the second edition (chapter 27).

A discussion of application protocols is included in the second half of the book. First, socket programming is briefly mentioned, then th e major application protocols are described: bootstrap protocol (BOOTP), dynamic host configuration protocol (DHCP), domain name system (DNS), Telnet, file transfer protocol (FTP), trivial file transfer protocol (TFTP), simple mail transfer protocol (SMTP), simple network management protocol (SNMP), and hypertext transfer protocol (HTTP) (chapters 15 through 25). Real-time traffic, multimedia applications, including voice over IP (VoIP), and the background RTP and RTCP protocols are introduced in chapter 28, which is newly added in this edition. Finally, the reader’s attention is directed to Internet security issues and solutions, including network address translation (NAT) and virtual private networks (VPNs).

Message formats and operations of the covered protocols are thoroughly described in the book. However, the second edition is slightly inconsistent, simply placing new chapters at the end of the book, without considering their relationship to the existing material. Additionally, I found that Internet security, primarily IP VPNs, is not sufficiently covered. There are other pieces of information that the reader might also miss, such as multiprotocol label switching (MPLS), layer two tunneling protocol (L2TP), and next hop routing protocol (NHRP). These protocols are not brand new, and one might expect them to be described in more detail. There is another important protocol, session initiation protocol (SIP), that is not even mentioned, but this could be due to its newness.

The writing and visual style of the book is very didactic, helping the reader to focus, and making the book suitable as a course textbook. There are hundreds of simple figures and highlighted points throughout the text, including numerous examples and analogies. Additionally, each chapter is equipped with a key terms list, summary, and test questions and exercises. I missed references to the RFCs throughout the text; there is only a brief list of RFCs related to main protocols (Appendix H). Also, I found incomplete discussions of protocols that have more versions, such as SNMP. It was not clear from the text which version is currently used, and what features belong to which protocol version. Apart from these subjective points, I can recommend the book as a reference on TCP/IP, and as a textbook.