http://www.rfc-editor.org/rfc/rfc2451.txt
RFC 2451: The ESP CBC-Mode Cipher Algorithms, R. Pereira, R. Adams1998-11-01T23:00:00-00:00This document describes how to use CBC-mode cipher algorithms with the IPSec ESP (Encapsulating Security Payload) Protocol. It not only clearly states how to use certain cipher algorithms, but also how to use all CBC-mode cipher algorithms. [STANDARDS-TRACK]