USER_CHAIN is a HTTP Header, as you have listed,
“USER_CHAIN” is our the standard for AAF at AT&T.name for the Property Tag
The format is a comma delimited set of entries:
...
Field 3: Protocol (BAth, OAth and x509 are best practice). These should be no more than 4 chars long for logging consistency.
Field 4 (Optional): Request (If Field 3 exists, and is “AS”, then the calling services is requesting that the Identity be treated as the official Identity
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