An illustrated guide to IPsec

"An Illustrated Guide to IPsec" is an excellent introduction to IPsec, written by software/network consultant Steve Friedl. I've read a number of overviews of IPsec recently, and this is by far the clearest explanation I've found of the basic AH/ESP, Tunnel/Transport Mode stuff. A little while back Steve wrote "An Illustrated Guide to Cryptographic Hashes", which was similarly lucid and helpful. Hopefully, he'll be writing some more crypto tech-tips soon.

While the article is a good explanation of the basics of what IPsec does, sadly, the article doesn't really cover why IPsec is the way it is. I'd like to read an "apology" for IPsec, explaining the somewhat complex, convoluted and perplexing architecture, and what the expected uses are for the various modes.

Tags: Cryptography , IPsec