HTTP field: Protocol-Request
Protocol-Request is a obsoleted 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 obsoleted; review compatibility before deploying it. Use Protocol-Request only according to its defining specification. Defining reference: PICS Label Distribution Label Syntax and Communication Protocols.
Registry-backed field entry. The field is currently marked obsoleted by IANA. Defining reference: PICS Label Distribution Label Syntax and Communication Protocols.
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 obsoleted; 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: PICS Label Distribution Label Syntax and Communication Protocols
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