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AES-CBC draft: Tunnel mode, TTL field of inner header

Dear all,
I just came across one point in the Internet Draft "The AES Cipher Algorithm
and Its Use With IPsec", <draft-ietf-ipsec-ciph-aes-cbc-04.txt>, June 2002
that made me wonder. In the last two test vectors (7&8) provided with the
draft ESP packets in tunnel mode are encryted with AES-CBC. Although RFC 2401
specifies in (5.1.2) to decrement the TTL field of the inner header this is not
done in the two mentioned test cases:

----------------
Case #7:

Original packet:
IP header (20 bytes): 45000054 09040000 4001f988 c0a87b03 c0a87bc8
                                        ^^
.
.
.

Pre-encryption Data with original IP header, padding, pad length and
next header (96 bytes):
45000054 09040000 4001f988 c0a87b03 ...
                  ^^

------------------

And also the ciphertext is based on the plaintext with TTL = 40.


Mistake? Changes in the specification?


Thanks,
Peter Mathes


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