[[http://openid.bitbucket.org/openid-connect-standard-1_0.html#protocol_flows| Dec 22, 2011 version of Draft 07]] says about Grant flows like this:
2.2. Protocol Flows
Authorization Requests follow two main paths to obtain Access Tokens and ID Tokens, the Implicit Flow and the Authorization Code Flow. .... "
Other flows like Client Credentials flow with "[[http://self-issued.info/docs/draft-jones-oauth-jwt-bearer-02.txt | JSON Web Token (JWT) Bearer Token Profiles for OAuth 2.0]]" can be allowed or not ?