Protocol definition acronym - SAVEP

One colleague from my past gave me this definition of what any Protocol needs to have at very least. The following it is:

"SAVEP" - Service, Assumptions, Vocabulary, Encoding, Procedural rules.

Service - What does it do.
Assumptions - Obvious.
Vocabulary - What can be said in the protocol.
Encoding - How are the messages encoded.
Procedural - How does it operate timeouts, fallback, error handling all the drama.

Thank you John!