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VOOT2 protocol from SURFnet
Maarten Kremers confirmed that VOOT2 is only about GETs.
VOOT2 protocol expressed as valid swagger2. See VOOT2 swagger yaml used for input into editor.swagger.io (to obtain resulting swagger API documentation).
SCIM: See both the Protocol Specification RFC7644 and Core Schema Specification RFC7643. Marlena Erdos comment: Quite rich group operations for read (and search) and write, quite fully documented -- and quite low level. Applies to a client contacting a server (natch, but this in contrast to Grouper)
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