topic Registered
Verified 2026-09-19 · registry updated
2026-07-20HTTP registry: tag
An application-specific tag for a signature
HTTP parameter values extend negotiation, framing, preferences, range handling, or other protocol components. tag is registered in HTTP Signature Metadata Parameters. Defining reference: RFC 9421, Section 2.3.
httpregistryhttp-message-signaturesignature-metadata-parameters
Identifier (http)
tag
An application-specific tag for a signature
Interpret parameters only in the context that defines them; unknown parameters must not silently change security or framing behavior.
This registry value is currently marked active by IANA. Follow the defining specification before sending, accepting, or proxying it.
IANA registry: http-message-signature/signature-metadata-parameters
Registry reference: RFC 9421, Section 2.3