JOSE Header (
Javascript Object Signing and Encryption Header) the members of the
JSON object(s) representing the
JOSE Header describe the
Digital Signature or
MAC applied to the
JSON Web Signature (
JWS) Protected
Header and the
JWS Payload and optionally additional properties of the
JWS.
The Header Parameter names within the JOSE Header MUST be unique; JWS parsers MUST either reject JWSs with duplicate JOSE Header Parameter names or use a JSON parser that returns only the lexically last duplicate member name, as specified in Section 15.12 (The JSON Object) of ECMAScript 5.1 ECMAScript.
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