If I recall correctly what an implementor once told me, the work involved in taking the fields that are immutable, then hashing packet, then sticking those immutable fields back in is actually more work than encrypting. Surprised me at the time but seems to be the case. - merike On Nov 13, 2009, at 7:09 PM, sfouant@shortestpathfirst.net wrote:

I've seen some vendor implementations in which ESP actually outperformed AH during performance testing... go figure...

Stefan Fouant ------Original Message------ From: Jack Kohn To: nanog@nanog.org Subject: AH is pretty useless and perhaps should be deprecated Sent: Nov 13, 2009 7:22 PM

Hi,

Interesting discussion on the utility of Authentication Header (AH) in IPSecME WG.

http://www.ietf.org/mail-archive/web/ipsec/current/msg05026.html

Post explaining that AH even though protecting the source and destination IP addresses is really not good enough.

http://www.ietf.org/mail-archive/web/ipsec/current/msg05056.html

What do folks feel? Do they see themselves using AH in the future? IMO, ESP and WESP are good enough and we dont need to support AH any more ..

Jack

Sent from my Verizon Wireless BlackBerry