Refine the design for attribute communication between a central attribute authority and identity proxies

In order to implement the architecture detailed in the SRCNet AAI design principles, the key concept of a central attribute authority needs to be tested and understood. A proof-of-concept using an INDIGO IAM instance has been deployed, and the methods through which this can be utilized must be understood.

A clear attribute API should be available, which can be utilised to obtain authorisation information

The current status of how the INDIGO IAM may perform in this role should be understood, and what is needed for a scalable future service is identfied

The Schema implications and requirements for integrating with existing communities and infrastructure - such as the existing IVOA infrastructure - must be understood and documented.