API Authentication/Authorization not clear and should leave scope for other auth mechanisms

The spec talks about basic auth requirement:

"Each request will be authenticated using HTTP Basic Authentication [RFC2617] unless otherwise noted."

(Above, what does "will" mean, is it intended to be a MUST?)

Unless I missed it somewhere reading the spec, looks like it does not talk about other authentication/authorization mechanism such as OAuth2. OAuth2 is still a draft but in practice its implemented/used by many. For example, if a "application developer", might be able to use OAuth2 access token[1] as HTTP Authentication header[2] or in some cases as URI query parameter while calling a vendor's CAMP APIs.

It sounds like the spec intends to mandate basic auth as the only authentication mechanism. Perhaps it should allow OAuth2 or other authorization/authentication mechanism as extensibility or keep it open and adopt OAuth2 as it evolves during spec development.

[1]http://tools.ietf.org/html/draft-ietf-oauth-v2-27#section-7

[2]http://tools.ietf.org/html/draft-ietf-oauth-v2-bearer-19

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