I owned the original first edition of Volume 1 and purchased the second edition for coverage of the new material. I think that Fall did an admirable job of adding the new coverage of things that have arisen since the first edition was written, but I was very disappointed in the writing style.
I disagree with the other reviewers who state that Fall retains the excellent writing style of the original. Whereas Stevens is known for succinct, clear prose that covers topics in a straightforward, readable way, Fall seems to have felt that adding verbosity was a necessary step in adding additional topic coverage.
For an example, just read the first page of the introduction for both editions. I had read the first edition a few years ago and was amazed at how Stevens made even the complex subjects easily understandable, but I paused while reading Fall's edition half-way through the introduction, asking myself "Why is this prose so difficult to understand? I don't remember the original being like this." After showing both editions to a friend of mine who is an English professor, she said that she is going to use excerpts from each book as a way to contrast good technical writing with bad technical writing (first edition, good; second edition, bad). In fact, after reading the first paragraph of the introduction of the second edition, she laughed at the quoted dictionary definition of "protocol," noting that English professors joke among themselves about how they all have to re-train high school graduates not to do this, since it is such a bad practice and so common among incoming college freshmen.
While speculating about why the editions are so different, I hypothesized that when Stevens was learning network programming, there was very little written material, and he had to figure out a lot on his own or ask many of the original authors of the software for explanations; Fall, however, had at his disposal much more written material, and his edition reads as if he is creating a compendium to summarize everything he could find.
I don't mean to make Fall feel bad about the amount of work he's done in updating Steven's excellent book; it was welcome. However, I wanted to caution potential buyers of this edition that they might be better served by purchasing a copy of the first edition for learning about TCP/IP and buying a copy of the second edition to use as a reference. Wading through Fall's edition to find the most important points of TCP/IP networking would be much harder and require much more work.
