Re: Extended seq number

Ramana Yarlagadda <ramana.yarlagadda@analog.com> Tue, 23 April 2002 21:09 UTC

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Date: Tue, 23 Apr 2002 13:39:13 -0700
To: Stephen Kent <kent@bbn.com>
From: Ramana Yarlagadda <ramana.yarlagadda@analog.com>
Subject: Re: Extended seq number
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>>I am going thruough the Draft-ietf-ipsec-esp-v3-02.txt.
>>
>>1)  Extended Sequence number is of 64bits (optioanally) and  the ICV is 
>>calucluated over the entire 64bits.but the sequence number 
>>transmitted  is of 32 bits , to keep the overhead low.
>>
>>Because of  this requirement  implementaion becomes quite complex, at 
>>least not straight forward.  what  we frame (IPSec header) is different 
>>from what we send.
>>
>>
>>-cheers
>>-ramana
>
>The high order 32 bits of the ESN are appended to the packet specifically 
>to make it easier to strip them prior to transmission. I don't know how to 
>make it easier, and still not send the extra bits.

Sorry, I have missed it and this is what exactly i am looking for.

-thanks
-ramana

>Steve