The Open Source Zone

I was painfully underwhelmed when I sat down at the bookstore for about an hour with a coffee and this book. Basically, it's a semi-unrelated series of whitepapers very pointedly aimed at management types. If you're looking for persuasive essays about how directories can increase your ROI, by jingo, this is your book. You may also be introduced to some new buzzwords while you're at it. Unfortunately, if you want either the big picture of how an LDAP directory works or the nuts-and-bolts of LDAP administration, this isn't your book.

I was looking for a book that would tie together the bits and pieces of LDAP knowledge that I had gathered from the internet for a thorough overview of LDAP. But after reading this book, I still don't have a clear understanding of basic concepts such as namespaces. One section led me to believe that a DNS-based namespace was the same as an LDAP hierarchical namespace, but then I had my doubts after reading another section. Are cn, ou, dc, and uid all object classes? I have heard that LDAP does not respond to a client with a pass/fail response, but there is a discussion of result codes in response to such operations. What are theses codes? When and how are they issued? Walk the reader through from beginning to end with an example of connecting to an LDAP server with a query or an authentication request and show the messages that are passed back to the client (if any). In a discussion of public key encryption, the author states: "the public key is published for anyone to know, whereas the private key is kept secret from everyone but the user....it doesn't matter who knows your public key, because the public key can't be used to impersonate you." Please explain this apparent paradox; if I need the public key to decrypt your message, and anyone can have the public key, then how is the data secure? Couldn't anyone tapping into our communication decrypt it if they have the public key too? Including some actual PERL, or JSP, or VB.NET with ASP.NET scripts for connecting to and querying an LDAP server would have been a plus.

It is difficult to write a technical book that doesn't merely present a collection of technical facts (which I will take on faith as being accurate). It is important to be able to state the facts plainly and connect them to form a coherent idea. For example: "A workgroup is just a group of workstations that share a browse list." I had read volumes about workgroups, workstations and browse lists in other books before finding this concise line (and many more like it) in a book by Mark Minasi. There is nothing for the reader to ponder or second-guess with such a line - it is short and to the point. As is, I didn't find a similar style in this book, nor did I find much information that isn't already freely available on the internet.

Suppose you were an administrator who is asked to run an LDAP-Server, but the only thing you know about LDAP is, that it is a fashionable IT-buzzword. Then this book is for you! If your task is to create a directory infrastructure for a whole company or organization, "LDAP Directories Explained" could be a perfect first read, but after it you will want to turn to a more comprehensive book. This book also does not claim to contain installation guides for any specific LDAP server implementation (though it has some links on this topic in one of its appendixes).

"LDAP Directories Explained" is well organized, specialized terms are being defined before they are used, there are no obvious typos and no useless digressions. Brian Arkills does a perfect job to make you understand the basic concepts of LDAP. He also makes you feel, that the LDIF-syntax which looks so deterring and obscure at the first look is in fact quite simple and he teaches you how to query an LDAP server. This is exactly the knowledge that is sufficent for 90% of the IT staff concerned with LDAP. Brain Arkill conveys it on only 200 pages. In the second half of the book he assesses three major LDAP-implementations: OpenLDAP, Microsoft Active Directory and Netscape Directory Server. We use neither of these, but the book was invaluable to me though.

I remember from my last job that the basic concepts of LDAP never were adequately explained in the Microsoft curricula, so I can also heartily recommend this book to Windows sysadmins.

Perhaps I just bought the wrong book for what I wanted to do, or maybe I just don't get it, but in either case, this book left me very underwhelmed.

I work at an ISP where we use LDAP for a number of purposes, from authenticating customers connecting to our network, to e-mail filtering, to htaccess authentication on our internal-use web servers. While I am comfortable using an LDAP browser to manage our users in LDAP, I really wanted more of an idea about how to set up and run an LDAP directory, so I bought this book to help me understand LDAP schemas.

While this book does describe a lot of the background to LDAP directories, it really didn't do much to fill in what I am missing. How do you design an LDAP schema? How do you know when to use ou=, o=, etc.?

On the plus side, I really *DID* appreciate the overview of various LDAP products currently available, and was pleased to see that all of the LDAP products I have used at work (OpenLDAP, iPlanet Directory Server and, or course, Active Directory) were described, along with their relative strengths and weaknesses. However, I really expected a little more meat--and maybe not quite as much background--about implementing an LDAP directory than I found in this book.

In short, if you want a general overview of LDAP directories, this might be what you want, but if you are looking for a "how to" guide, you probably should keep looking.

This is the book for people like me who
had heard about directories, but couldn't
get past the (&(cn=foo*)(ou=*Bar*)) notation
to figure out what was going on. The
book does an excellent job explaining how
LDAP directories can and should work
within an enterprise. Brian Arkills has
written a wonderful book.<p>Anyone who wants to learn some of the 'Why?'
about MS Active Directory would do well to
start here. The first half of the book lays
out the basics of directories, with numerous
references to standards documents (RFC's).
The rest iterates through popular LDAP
directory implementations, what they have to
offer, how they are 'special' and why you
might want to use them.