I thought this book to be useful, and I learned a good deal about public key cryptography and ssh in general. Sure there are some things I felt out of place (the server discussion in chapter 3 I felt could have come later). I thought the book to be useful overall. The discussion on configure/make/make install; while mundane to an experienced admin, would be invaluable for a novice. I felt that this book has value as a reference in SSH. The only suggestion I have is that a more thorough explanation of authenticating with public keys would have been helpful. In site of that, I believe this will be an excellent book with a few minor tweaks in a second edition. I am sure Ms. Carasik is reading these comments and taking them into consideration. The previous reviews of one star are a bit harsh. The comments about HOWTOs and man pages by previous reviewers are not necessary. If you look hard enough you can find all you need to do anything in man pages and HOWTOs. Books are for those of use who would rather have something more convenient.

I have to disagree with the previous reviewers; this is a very useful book. In style it reads like a software manual--but don't take me wrong! I mean that the author provides lots of details, exactly the sort of information I was looking for before installing the program. I felt that the author's walkthrough of the "configure" process, which another reviewer criticized as unnecessary, was nicely annotated and gave an excellent feel for the process of installing SSH. I'll admit that a lot of people have seen "configure" do its stuff a thousand times before and can skip this section. For relatively inexperienced sysadmins, however, this kind of detail is reassuring and valuable.
The author writes as a person who understands the operation of the programs in detail; sometimes you get little tidbits that seem oddly out of place in a user's guide (such as the discussion of child process forking in Chapter 3, which seemed to have offended one reviewer so badly), but which I thought were clearly explained. I didn't notice any technical errors in the author's explanation of clients, servers, and daemons, and I write code like this for a living. It's a good explanation, probably lots more detail than most people ever wanted to know, and it might be better relegated to an appendix, but there's nothing wrong with it, and I enjoyed it. Lighten up, people; if you don't care about the details, then skip it. (Note to the author: if you ever decide to write a book on client/server programming, call me!)
It's true that you can find a lot of the same information in scattered FAQs and mailing list archives on the net. But I've seen a growing number of HOW-TO's and web pages out there, set up by pioneers who struggled with earlier versions of SSH; after finally getting it to work, they wanted to spare others the pain they encountered while at the same time saying, "Look! I got it to work!" This book brings a lot of useful information together in one place. For the next edition, more details on Windows NT clients would be appreciated, but for Unix, this is THE book for ssh right now.
"I want my fourty (sic) dollars back," is a terribly devastating (and very funny!) review, but I don't think it's deserved. I almost didn't buy this book for a long time, after reading the early, poor reviews. I'm mad at myself now for not buying it sooner--it's a good book and doesn't deserve the poor press.
This is the only book available on SSH right now; it's right up to date, and it's well-written. I highly recommend it.

I disagree with the three people previous to me who reviewed this book. I found it to be a great beginner's reference for compiling, installing and configuring Secure Shell (SSH), as well as learning some of the additional tricks it can do.
I have been using SSH for about two years, on AIX and Solaris. I learned a lot from Chapters 8 & 9 about using SSH through firewalls as a sort of "poor man's" VPN. The book also spells out the difference between the 1.5 and 2.0 protocols.
UNIX System Administrators with little or no knowledge of SSH will find this to be an excellent, step-by-step guide. Experienced users may learn something they didn't know. There are some minor errors, but overall they have no impact on the usefulness of the book.
Developers who are looking for tips on modifying, enhancing or otherwise hacking SSH code will not find much here to help them.
A book like this is long overdue and I'm glad somebody finally wrote it.

I bought the book after meeting Ms. Carasik at the RSA conference last March. It is useful as a high level overview, but one cannot trust the details. In some places, the author appears to simply make stuff up. For example, on p118, the SSH_AUTH_SOCK variable is correctly defined but is also claimed to be related to the SOCKS network proxy. On p243, it is suggested that the reader use "something like Perl or a shell script" to generate the random number needed for setting up X authentication. I had to search the Web to find a one-line perl expression to do this, and then I had to refer to volume 8 of my O'Reilly X set to figure out how X authentication really works. Very disappointing!
If I were in the market for a Secure Shell book today, I'd wait for the new one coming from O'Reilly. Use this one only as a last resort and only if you mostly know what you're doing.

I am still learning the duties of system adminstration for my Linux box and I have had a need for secure shell for some time. Despite a concern that arose from earlier reviews, I did purchase the book, "Unix Secure Shell".
While on one hand the book is not nearly as bad as described in an earlier review, I must agree that it is a poor example of technical writing. I found the book confusing and irritating. The author has a tendency to make awkward statements that leave me guessing. Topics and figures are presented out of context.
I am hoping to use secure shell to help backup my system. Unfortunately the book covers this topic in only about two pages. While somewhat informative, do not rely on this book as a primary reference.