Trillian Secure IM

[Bill Stewart]

> > | Which is by the way exactly the case with SecureIM. How
> > | hard is it to brute-force 128-bit DH ? My "guesstimate"
> > | is it's an order of minutes or even seconds, depending
> > | on CPU resources.

Sun's "Secure NFS" product from the 1980s had 192-bit Diffie-Hellman,
and a comment in one of the O'Reilly NFS books says that
         "However, by 1990, advances in RISC processors produced
         workstation machines that could, by brute force,
         derive the private key from any public key in under a day."
but that in 1987 there were still a lot of Motorola 68010 machines
that took several minutes to generate keys so they didn't want it longer.
I'm guessing that a 1990 RISC machine was around 50 MIPS,
so it's maybe 1/100 the speed of a modern single-core CPU.

128-bit DH sounds like as good a decision as using 40-bit RC4 keys would be 
today.

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