802.1X Port-Based Authentication

I work for a network test equipment developer and have to test devices with multiple security types by multiple security device vendors.
Most all enterprise security uses 802.1x whether wired or wireless. To many, 802.1x can be confusing at best, and mind-blowing at its worst.
Edwin Brown's book is the best I read on the subject. It's a book that explains the concepts that are the building blocks of 802.1x in a conversation tone that neither talks over the heads of interested parties or simplify the subject to the point of being meaningless babble.
Brown's style of writing comes across as sitting and listening to a very knowledge colleague help you to understand a subject. Brown's presents the information to you on an equal to equal basis so that you just "get it".
The technical information is clear and thorough and serves as an excellent reference when you need to dig into a specific issue of 802.1x
I'm pleased to have it on my bookshelf at work.