Yeah, I know, 1998. Old news, but anyway...
Down at the end, we see
Update:  I've now installed the Perl module for it. Go me.
RFC 2410If you're in a hurry, you can skip down to '2.4 Performance' or 'Intellectual Property Rights'.
Down at the end, we see
Credit also needs to be given to the participants of the Cisco/ICSA IPsec & IKE March 1998 Interoperability Workshop since it was there that the need for this document became apparent.at one of the late-night sessions after too many beers, clearly...
Update:  I've now installed the Perl module for it. Go me.