[OTR-dev] DH moduli size

[Fedor Brunner]

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Hi,
in year 2005 there was discussion about increasing the moduli in OTR
from 1536-bit discrete logs to longer key sizes. We have now year 2014
and performance improvement in computers allow much longer key sizes
even in embedded devices.

https://lists.cypherpunks.ca/pipermail/otr-users/2005-March/000186.html

Are the limitations of ICQ still relevant for OTR ?

https://lists.cypherpunks.ca/pipermail/otr-users/2005-March/000190.html

I recommend also reading the
"Yearly Report on Algorithms and Keysizes (2012), D.SPA.20 Rev. 1.0,
ICT-2007-216676 ECRYPT II, 09/2012."
http://www.ecrypt.eu.org/documents/D.SPA.20.pdf
http://www.keylength.com


Recently there was theoretical progress for the discrete logarithm problem:
http://hal.inria.fr/hal-00835446

If performance is the primary problem with longer DH moduli, have you
considered to switch elliptic curves? They support faster calculation
and shorter key sizes. For example Curve25519, Curve3617, or E-521 ?

http://safecurves.cr.yp.to/index.html

Regards,
Fedor



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