[WG-UMA] New design principle/requirement around digital signatures?

Eve Maler eve at xmlgrrl.com
Thu Jan 27 14:34:20 EST 2011


Since we've got a lot of folks who have joined the group since we last looked at the Requirements doc together, here's a little context/preamble about this doc:

http://kantarainitiative.org/confluence/display/uma/UMA+Requirements

We have allowed our requirements and design principles to be "emergent".  We started out with bootstrap sets of them that came from our charter, but we have subsequently captured them only when it seems we have a shared assumption (hallucination?) that's strong and focused enough to record.

In today's call, it was clear that we find a lot of value in leveraging digital signatures as the methods for using them become more unambiguous, interoperable, and applicable to our use cases.  With JWT getting more developed, we can make use of our DP5 around "modularity", by citing an external spec and only profiling it as necessary.

Since we have DPs and Rs around simplicity, adoption, sequestering complexity in the AM, avoiding new crypto burdens, etc., we may have gone a bit overboard, appearing to be wholly in the "anti-cryptarian" sect.  In fact, we know we are interested in solving use cases that involve strong needs for security and privacy (hData being only one) and -- in the fullness of time -- trusted claims in general.  Lots of use cases involving higher levels of assurance (in the lowercase, informal sense) do rely on stronger authentication, and JWT may ride to the rescue for these.

Proposal:

Since a DP is a general statement of goals and a requirement is something for which we can measure judge "conformance", I think this wants to be a DP.  I propose the following as a strawman:

Title: Digital signatures

Principle: Don't preclude strong authentication through digital signatures, and leverage and adopt signatures as options if a reasonable measure of interoperability can be achieved.

Explanation/commentary: We see opportunities to leverage JWT that didn't exist when the group was first launched, and we have more overall experience with judging what is "reasonable" vs. "undue" crypto burdens now (see DP8, "Cryptography").  This principle mitigates the potentially heavy-handed effects of DP1 ("Simple") and DP10 ("Complexity") in forcing bearer tokens as a universal solution.  Finally, this principle is consistent with DP11 ("Authentication") if we leverage an external spec for digital signatures and avoid defining a whole new one.  This was discussed on 2011-01-27 [and other dates, TBS].


Comments?  If we get consensus on this wording or a revision by next week, let's go ahead and do a vote on it.

	Eve

Eve Maler                                  http://www.xmlgrrl.com/blog
+1 425 345 6756                         http://www.twitter.com/xmlgrrl



More information about the WG-UMA mailing list