In A Quarter Century of Unix Peter Salus explored the history of Unix; in Casting the Net he turns to the history of the Internet. After a brief look at the “prehistory” of networking, he covers the development of the ARPANET in some detail. He then discusses a variety of material, organised thematically and roughly chronologically: early networks in Europe and Japan (but nothing about Australia); the development of new protocols (particularly for mail); the switch to TCP/IP; the OSI protocol wars; UUCP and Usenet; BITNET and Fidonet (and a bit on IBM's VNET); the NSFnet; the NREN and the NII; the most recent commercialisation and explosion of the Internet; and so forth. Information is current up to December 1994, so Casting the Net is not too badly out of date.

In a couple of places Salus pretends he's writing a book for the masses---at one point he devotes a couple of pages to explaining the difference between datagram- and circuit-based networks, for example---but this pretence is not maintained---while Casting the Net doesn't assume a great deal of technical knowledge, it is still very much a technical history, written for those who work with networks and networking protocols. For example, the book includes all the April Fools' Day RFCs, material that can hardly be appreciated by anyone who's never read an RFC or tried to understand a networking protocol.

Whereas A Quarter Century of Unix was built out of quotes, more of Casting the Net is taken up by diagrams, time lines, and digressions. Most of these are reprinted from easily accessible sources (like the digressions, many of the quotes are from RFCs), so there is a lot less original material than in the earlier book, and I don't think it is as impressive an achievement. It includes a lot of good material, however, and it's a good read; once again, I finished it within a day of receiving my copy. As a compact technical history of the Net, it doesn't have much competition.