Are there any alternatives to SASL? Is there another standard authentication framework that abstracts the authentication mechanism from the protocol in the way that SASL does?
To be more specific about my interest in this: I am looking for a standard that will enable me to implement an easily extensible authentication layer to an application. I like that a SASL-enabled application says "these are my supported mechanisms; pick one." Is there some alternative out there that defines a set of authentication mechanisms and a protocol for presenting their availability to users?