Sam, In skimming through Nico's draft, it looks like EAP's crypto bindings look something like GSS channel bindings. EAP's channel bindings, on the other hand, don't really look like GSS channel bindings. In order for EAP's channel binding to look like GSS channel binding, EAP channel binding would have to cryptographically bind an L2 security association to EAP keys -- but that's not what it's doing. It's binding L2 identities to EAP keys. In fact, there's no reason it has to be an L2 identity. It can be any identity that's meaningful to the parties involved, and can serve as the basis for making authorization decisions. Perhaps you could abstract the definition of channel bindings even further such that all three are subsets of some common terminology... but that sounds painful. -- t. charles clancy, ph.d. <> tcc@xxxxxxx <> www.cs.umd.edu/~clancy On Fri, April 6, 2007 1:43 pm, Sam Hartman wrote: > > > > Hi. > > For the last couple of years, we've been believing that EAP and GSS > used the term channel bindings inconsistently. For those of us > dealing with both, it's been a bit annoying. > > I've been thinking about EAP a lot lately. and have come to the > conclusion that actually the terms are used consistently. > > I'd like to see if people agree with the following change to Nico's > channel binding draft: > > old: > > Also unfortunately there is a conflict with the Extensible > Authentication Protocol (EAP) [RFC3748] which uses "channel binding" > to refer to a facility that is subtly different from the one > described here. (It does not seem feasible to adopt new terminology > to avoid these problems now. The GSS-API, NFSv4 and other > communities have been using the terms "channel binding" and "channel > bindings" in these ways for a long time, sometimes with variations > such as "channel binding facility" and so on.) > > new: > > The Extensible Authentication Protocol (EAP) [RFC3748] includes two > facilities related to channel binding. The first, called channel > binding, is used to bind the lower-layer channel created between the > peer and the authenticator to the authentication performed using EAP. > Specific detials of this facility have not been specified, but it is > likely that this channel would use endpoint channel bindings carried > in the EAP method exchange. The endpoint channel bindings would be > defined for the specific lower layer. EAP also has a facility called > cryptographic binding, which is another instance of channel binding. > Cryptographic binding refers to binding the channel created by a > tunneling EAP method to an inner authentication performed within that > method. Cryptographic binding will likely use unique channel > bindings. > > Do these changes make sense to people? Am I telling any lies or > conflating two architectures in a bad way? > > > _______________________________________________ > Emu mailing list > Emu@xxxxxxxx > https://www1.ietf.org/mailman/listinfo/emu > _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf