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Maciej Machulak is the UMA group's implementation coordinator. Key implementations are noted below, in alphabetical order of the project or organization.
SMART project
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Cloud Identity UK
This company (also at @CloudIdentityUK) offers a commercial UMA authorization server suite based on SMART AM (see below).
Fraunhofer AISEC project
This Java implementation has been contributed to Apache Amber. Developer documentation is available. Update from the team as of 9 Jul 2012: "UMA client, AM, and Host are running now within AISEC domain and will be accessible from the outside after receiving the security clearance from our network team".
OXAuth project
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The company Gluu (also at @GluuFederation) hosts the OXAuth open-source project, to which it has contributed an UMA component.
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The main use case for this implementation is enterprise usage
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SMART project
This Java implementation includes an UMA/j framework and sample applications. See the SMART blog. The OAuth portion, originally named leeloo, has been contributed to Apache Amber. Part the SMART project involves development of set of open-source Python libraries, called Puma, for UMA-enabling web apps to become UMA hosts and requesters.
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