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Federation peering à la European The eduGAIN way. Diego R. Lopez - RedIRIS. As Federations Grow. The risk of dying of success Do we really need to go on selling the federated idea? Different communities, different needs Not even talking about international collaboration
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Federation peering à la EuropeanThe eduGAIN way Diego R. Lopez - RedIRIS
As Federations Grow • The risk of dying of success • Do we really need to go on selling the federated idea? • Different communities, different needs • Not even talking about international collaboration • Different (but mostly alike) solutions • Grids and libraries as current examples • And many to come: Governments, professional associations, commercial operators,… • Don’t hold your breath waiting for the Real And Only Global Federation
Confederations Federate Federations • Same federating principles applied to federations themselves • Own policies and technologies are locally applied • Independent management • Identity and authentication-authorization must be properly handled by the participating federations • Commonly agreed policy • Linking individual federation policies • Coarser than them • Trust fabric entangling participants • Whitout affecting each federation’s fabric • E2E trust must be dynamically built
First Steps • Simplifying user collaboration across whatever border is an excellent selling argument • Making the whole promise of the VO idea • eduroam fast worldwide success is a clear example • Lingua franca • Syntax: SAML profiles • Converging to 2.0 • Semantics: eduPerson, SCHAC • Trust fabric • Public key technologies (if not infrastructures) • Component identifiers and registries • Metadata repositories
Policy and Legal Matters • The PMA model has proven extremely useful • Consensual set of guidelines • Peer-reviewed accreditation • Legal matters: Hic sunt leones • For techies like us • Privacy • Liability • More or less manageable in the case of (national) federations
The AAI Goal in GÉANT2 • To build an interoperable authentication and authorisation infrastructure that will be used all over Europe enabling seamless sharing of e-science resources • We started from • Scattered AAI implementations in the EU and abroad • And growing • The basic idea of federating them, preserving hard-won achievements
Applying Confederation Concepts • An eduGAIN confederation is a loosely-coupled set of cooperating identity federations • That handle identity management, authentication and authorization using their own policies • Trust between any two participants in different federations is dynamically established • Members of a participant federation do not know in advance about members in the other federations • Syntax and semantics are adapted to a common language • Through an abstract service definition
The eduGAIN Components • Bridging Elements (BE) • Interconnection points • Federation-wide (LFA) or distributed (LA) • Federation Peering Point (FPP) • Able to announce BE metadata • The Metadata Service (MDS) • Publishing interface (to FPPs) • Querying interface (to BEs)
Connect. Communicate. Collaborate The eduGAIN Model Metadata Query MDS Metadata Publish Metadata Publish R-FPP H-FPP R-BE H-BE AA Interaction AA Interaction AA Interaction Resource(s) Id Repository(ies)
Connect. Communicate. Collaborate IdP IdP IdP IdP IdP IdP IdP SP SP SP SP SP SP SP SP SP An Adaptable ModelFrom centralized structures... MDS FPP FPP BE BE
Connect. Communicate. Collaborate BE BE BE BE BE BE BE BE IdP IdP IdP BE BE BE BE IdP IdP IdP IdP SP SP SP SP SP SP SP SP SP BE BE BE BE An Adaptable Model...to fully E2E ones... MDS
Connect. Communicate. Collaborate BE BE BE IdP IdP IdP BE IdP IdP IdP IdP SP SP SP SP SP SP SP SP SP BE BE BE BE An Adaptable Model...including any mix of them MDS FPP FPP BE
The (X.509) Trust Fabric • Validation procedures include • Normal certificate validation • Trust path evaluation, signatures, revocation,… • Peer identification • Certificates hold the component identifier • It must match the appropriate metadata • Applicable to • TLS connections between components • Two-way validation is mandatory • Verification of signed XML assertions
Component Identifiers • eduGAIN operations strongly depend on having unique, structured and well-defined component identifiers • Based on URNs delegated by the eduGAIN registry to the participating federation • Identifiers establish the kind of component they apply to by means of normalized prefixes • Identifiers follow the hierarchy of the trust establishing process
Connect. Communicate. Collaborate urn:geant2:...:requester urn:geant2:...:responder A General Model for eduGAIN Interactions https://mds.geant.net/ ?cid=someURN <samlp:Request . . . RequestID=”e70c3e9e6…” IssueInstant=“2006-06…”> . . . </samlp:Request> <samlp:Response . . . ResponseID=”092e50a08…” InResponseTo=“e70c3e9e…”> . . . </samlp:Response> MDS TLS Channel <EntityDescriptor . . . entityID= ”urn:geant2:..:responder"> . . . <SingleSignOnService . . . Location= “https://responder.dom/” /> . . . TLS Channel(s) Requester Responder Resource Id Repository
Operation Mapping • Maps the abstract service definition into actual protocols • Current version is based on SAML 1.1 • Profiling the standard to fit abstract parameters • A SAML 2.0 implementation will be available along the lifetime of the project • The abstract service specification protects components and applications from these changes • Authentication assertions and attribute exchange mechanisms are designed to be Shibboleth 1.3 compatible • And Shibboleth 2 in the future
Metadata Service • Based on REST interfaces transporting SAML 2.0 metadata • Usable by non-eduGAIN components • Metadata are published through POST operations • Metadata are retrieved through GET operations • URLs are built as MDSBaseURL/FederationID/entityID?queryString • Using component names • The query string transports data intended to locate the appropriate home BE (Home Locators) • Hints provided by the user • Contents of certificate extensions (SubjectInformationAccess)
Connect. Communicate. Collaborate A Layered Model for Implementation Component logic eduGAINBase Profile Access eduGAINBase + eduGAINVal + eduGAINMeta SAML toolkit (OpenSAML) SOAP/TLS/XMLSig libraries
eduGAIN Profiles • Oriented to • Enable direct federation interaction • Enable services in a confederated environment • Four profiles discussed so far • WebSSO (Shibboleth browser/POST) • AC (automated cilent: no human interaction) • UbC (user behind non-Web client: use of SASL-CA) • WE (WebSSO enhanced client: delegation) • Others envisaged • Extended Web SSO (allowing the send of POST data) • eduGAIN usage from roaming clients (DAMe) • Based on SAML 1.1 • Mapping to SAML 2.0 profiles along the transition period
Connect. Communicate. Collaborate The AC Profile
Connect. Communicate. Collaborate The UbC Profile
Connect. Communicate. Collaborate The WE Profile
Connect. Communicate. Collaborate The WebSSO Profile
The European Way • (Too) many governments, languages, national priorities/laws/prides/… • A little of weakness, a little of strength • The will for convergence • Without imposing dramatic inner changes • Adopt whatever is worth from overseas • With a scent of style and history • (Humble) model for the rest of the world • We are a little world in itself