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1Support for SAML 1.0 is minimal and mostly accidental with current releases.
2 Implemented as part of SSO profile support, exposed through additional features in SP 2.6.
3 Implemented only in the form of application notification hooks for IdP-initiated protocol. SP-initiated not supported.
4 HTTP-Artifact binding only supported outbound to SP, not inbound.
5 Implemented to rely on SPSSODescriptor role in metadata, no support for query extension role as yet.
6 The basic variant is in the core since IdP 2.3. The delegated variant requires an extension. See ECP for details.
7A first implementation of real Single Logout was added in IdP 3.2 and is still under active development.
8A supported third-party extension is available for V3 and will be migrating migrated to an official a Shibboleth git repository for V4. Substantial configuration instability should be expected between now and an eventual "stable" version delivered with V5 (no sooner than 2021).
9Introduced in IdP V3, see documentation for specifics on features
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