[IPsec] Diet-ESP

[Daniel Migault <[e-mail]>]

Hi,

Here are the drafts we wrote on Diet-ESP which designs ESP for constrain
environment.

[1] draft-mglt-ipsecme-diet-esp-requirements-00.txt
<http://datatracker.ietf.org/doc/draft-mglt-ipsecme-diet-esp-requirements/>
provides the requirements we considered for the design of Diet-ESP
[2] draft-mglt-ipsecme-diet-esp-01.txt
<http://datatracker.ietf.org/doc/draft-mglt-ipsecme-diet-esp/>
describes Diet-ESP. According to feed backs we received during the
last presentation. Diet-ESP does not modify ESP. Instead, we consider
compression / decompression of the payload sent on the wire.
[3] draft-mglt-ipsecme-diet-esp-iv-generation-00.txt
<http://datatracker.ietf.org/doc/draft-mglt-ipsecme-diet-esp-iv-generation/>
describes a way to compress th IV field in ESP encrypted payloads.
[4] draft-mglt-ipsecme-diet-esp-payload-compression-00.txt
<http://datatracker.ietf.org/doc/draft-mglt-ipsecme-diet-esp-payload-compression/>
describes how IPsec parameters negotiated with IKEv2 can be used to
compress the clear text payload. More specifically, it is expected to
compress up to the transport layer of the encrypted packet.

Feel free to make comments!

We have specific question regardin the IV compression. The general idea is
that a speudo random function is used on bth side to generate the IV. This
makes possible to send only some LSB.
    - 1) The pseudo random function uses as input the encryption key an
dthe authentication key. I do not see major security flaws, but it may be
better if a dedicated K could be used. Any ideas?
    - 2) By default we use PRF_AES128_XCBC. Another way would consist in
chosing the PRF based on the ICV function. When NULL authentication is used
the IV would not be compressed. Any opinion on that too?


[1]
http://datatracker.ietf.org/doc/draft-mglt-ipsecme-diet-esp-requirements/
[2] http://datatracker.ietf.org/doc/draft-mglt-ipsecme-diet-esp/
[3]
http://datatracker.ietf.org/doc/draft-mglt-ipsecme-diet-esp-iv-generation/
[4]
http://datatracker.ietf.org/doc/draft-mglt-ipsecme-diet-esp-payload-compression/
-- 
Daniel Migault
Orange Labs -- Security
[phone]