R1 spec defines that clientID should be extracted from JWT in request header.

Investigate how to reuse this for 'serviceID' when creating an A1 Policy

Need to investigate where ServiceID may also be present as an optional request parameter.

Also need to be able support where a Token is not provided.

Note, this ticket is not enforce authentication/access control - just get a value for service ID.

Authentication/Access control is handled in Service Mesh or using the Authorization call-out interface.