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• Header
  • typ: The type of the token, which is JWT
  • alg: The hashing algorithm being used, which is HS256
• Payload: contains the claims which are statements about an the user and additional metadata.
  • jti: The ID of the user session as generated by CRM.COM
  • usr: The username of the logged in user
  • org: The organisation name of the organisation that the user logged in
  • oun: The unit name of the unit that the user logged in
  • exp: The expiration time on or after which the JWT becomes invalid and should not be accepted for processing. 
  • iat: The time at which the JWT was issued
• Signature: is used to verify that the sender of the JWT is who it says it is and to ensure that the message wasn't changed along the way. The signature is created by encoding the header and payload and signing them using a secret and the HS256 algorithm

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• encoded header + '.' + encoded payload + '.' + encoded signature
  
  

Note that the JWT values are case sensitive. Also the exp and iat claims are defined in as numeric dates. A numeric date is a JSON numeric value representing the number of seconds from 1970-01-01T00:00:00Z UTC until the specified UTC date/time, ignoring leap seconds. There are online tools that you can use to check and validate the JWT, such as the JWT Debugger and also to calculate and validate numeric dates, such as the Epoch Converter

How to Authenticate with Web API Key Method

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