AH:
RFC2402: IP Authentication Header.
RFC2404: The Use of HMAC-SHA-1-96 within ESP and
RFC2857: The Use of HMAC-RIPEMD-160-96 within ESP and
RFC4302: IP Authentication Header.
RFC4359: The Use of RSA/SHA-1 Signatures within Encapsulating Security Payload (ESP) and Authentication Header (AH).