Subject: [Megaco] Clarification for interim AH implementation (authentication header)

From: Narendra Babu <[email-masked]>
Date: Tue, 22 Jan 2002 19:17:29 +0530

Hi all

I have a doubt in security issue for Megaco.The RFC states
that we have to follow interim AH i,e through authentication header present within the megaco message.

            If  we  follow that track we will come across with
authentication data field present in the message.To fill this
we have to find ICV on whole transaction and synthesized
IP header (refer page no 69 of RFC).There are two algorithms to calculate ICV   1) HMAC-MD5-96
                                                                                                                   2) HMAC-SHA-1-96         

My doubt is how the receiving side will come to know whether HMAC-MD5-96  or HMAC-SHA-1-96  is used in the received message?

Can we get reference design for Interim AH anywhere ?

                                        Expecting your replies soon !

Thanks in Advance

Narendra