GNAP (Grant Negotiation and Authorization Protocol) is an in-progress effort to develop a next-generation protocol based on years of knowledge and experience with OAuth 2. This work is taking place in the GNAP working group at the IETF. Questions, suggestions and protocol changes should be discussed on the mailing list or GitHub.
The latest version of the in-progress specification can be found at tools.ietf.org/html/draft-ietf-gnap-core-protocol.
Read the design details and examples that motivated the original design at oauth.xyz. Early drafts of the spec were called "XYZ", "TxAuth", and "Transactional Authorization".
This specification is very much in progress, and interested readers are encouraged to participate in its development by joining the IETF Working Group or attending OAuth events.
See Also: OAuth 2.1, an officially adopted effort to consolidate and simplify the best practices of OAuth 2.0.