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Re: draft-ietf-ipsec-ah-md5-00.txt
> Ron Rivest has stated that a shared secret at the front of a message is not
> sufficient for authentication. I thought that I remembered this being
> discussed ath the San Jose IETF. Further, I thought that we agreed that we
> would solve this weakness by puting the shared secret before and after the
> data payload.
>
The appending attack is solved by including the IP Total Length field
in the calculation. Ran explained this.
> Does anyone else remember this? I seem to remember the discussion causing
> a tanget about "prepend" not being a word.
>
That was me. I remember. The WG minutes do not suggest a decision was
made. I have email from the Area Director recommending we only use
the front, as that is compatible with what other WGs are doing.
Bill.Simpson@um.cc.umich.edu