http://www.rfc-editor.org/rfc/rfc3686.txt
RFC 3686: Using Advanced Encryption Standard (AES) Counter Mode With IPsec Encapsulating Security Payload (ESP), R. Housley2004-01-01T23:00:00-00:00This document describes the use of Advanced Encryption Standard (AES) Counter Mode, with an explicit initialization vector, as an IPsec Encapsulating Security Payload (ESP) confidentiality mechanism.