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UMA is a protocol that describes a technical "contract" for HTTP-based interactions (such as standardized request and response messages involving standardized data formats) among compliant software entities. The entities fill various roles in order to achieve "user-managed access" to Web resources. The following diagram illustrates the high-level goal of UMA.
The following diagram illustrates the high-level architecture UMA uses to achieve its goal.
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Software Endpoints vs. Legally Responsible Parties
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