DMTF has a new version of the Security Protocol and Data Model (SPDM) spec.
“The SPDM Specification provides message exchange, sequence diagrams, message formats, and other relevant semantics for authentication, firmware measurement, and certificate retrieval.”
https://www.dmtf.org/content/dmtf-shares-plans-session-keys-spdm-11
https://www.dmtf.org/sites/default/files/standards/documents/DSP0275_0.95a.zip