There are not many IT books i read front to back, usually i just use them as Reference Manuals, or read the interesting chapters.
I bought “Doraswamy/Harkins – IPSec”, which gives a very good Overview over the topic. The only aspect that missed out was the use of PKI with IPSec.
Unfortunately most books about IPSec are from around 2001, when VPN where the hot topic.
So I am now looking over a good overview over recent developments regarding PKI, X509v3, CMP etc.