Re: IPsec and Fragmentation

Stephen Kent <kent@bbn.com> Wed, 08 July 1998 22:46 UTC

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Date: Wed, 08 Jul 1998 18:57:53 -0400
To: Karen Heron <heron@us.ibm.com>
From: Stephen Kent <kent@bbn.com>
Subject: Re: IPsec and Fragmentation
Cc: ipsec@tis.com
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Karen,


>Thanks for the clarification. (However, I'm having trouble finding section
>3.2.5 in my copy of the architecture doc (draft-ietf-ipsec-arch-sec-05)).  But
>I believe that the statement in Appendix B, section B.2, "Fragmentation MUST
>be done after outbound IPsec processing." is incorrect.  In fact, for a tunnel
>mode SA on a host, fragmentation must be done before IPsec processing to make
>PMTU discovery work, correct?

The section I cited is from the most recent version of the spec,
arch-sec-06, distributed to the list last week (7/2).  However, B.2 still
makes the same  statement in this version!  I could point out that the
appendices are not normative, but I guess it would be better to just fix it
:-).

Steve