HTTP field: Protocol-Info
Protocol-Info is a deprecated field in the IANA HTTP Field Name Registry.
HTTP fields are message metadata; their meaning depends on direction, combination rules, and the HTTP version carrying them. The registry marks this value deprecated; review compatibility before deploying it. Use Protocol-Info only according to its defining specification. Defining reference: White Paper: Joint Electronic Payment Initiative.
Registry-backed field entry. The field is currently marked deprecated by IANA. Defining reference: White Paper: Joint Electronic Payment Initiative.
Check whether the field is end-to-end or hop-by-hop, whether it varies a cache response, and whether it carries security-sensitive data before forwarding or logging it. The registry marks this value deprecated; review compatibility before deploying it.
Check the linked specification for its direction, combination rules, caching behavior, and security considerations before generating or trusting it.
IANA registry: http-fields/field-names
Registry reference: White Paper: Joint Electronic Payment Initiative
Sources