The specifications that make up Shibboleth are still undergoing development, to document existing practice, correct deficiencies in the original design, and track emerging SAML industry practice. The specification set is roughly divided into architecture and implementation, corresponding to the last two bullets above.

Architecture

The architecture specification consists of two documents:

Protocol Specification (profiles of SAML that dictate how implementations behave)
Conformance Specification (requirements that implementations claiming compatibility with Shibboleth must meet)

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