Re: SOI QUESTIONS: 2.2 Perfect forward secrecy (PFS)

[Bill Sommerfeld <sommerfeld@east.sun.com>]

Let's be careful to distinguish between:

 1) the forward-secrecy properties of IPsec key management

 2) the optional second DH exchange done in IKEv1 phase 2, which is
    what many people think of when they hear "PFS".

I don't believe that there's a need for every SA to have a separate DH
exchange; what is important is for the spec to allow a user of the
protocol to know what the forward-secrecy properties are, and that
requires protocol-visible lifetimes for keying material.

					- Bill