Today in HBase, we rely on SASL to implement Kerberos and delegation token authentication. The RPC client and server logic is very tightly coupled to our three authentication mechanism (the previously two mentioned plus simple auth'n) for no good reason (other than "that's how it was built", best as I can tell).

SASL's function is to decouple the "application" from how a request is being authenticated, which means that, to support a variety of other authentication approaches, we just need to be a little more flexible in letting developers create their own authentication mechanism for HBase.

This is less for the "average joe" user to write their own authentication plugin (eek), but more to allow us HBase developers to start iterating, see what is possible.

I'll attach a full write-up on what I have today as to how I think we can add these abstractions, as well as an initial implementation of this idea, with a unit test that shows an end-to-end authentication solution against HBase.

cc/ wchevreuil聽as he's been working with me behind the scenes, giving lots of great feedback and support.