2.5.3 Federated Digital Identity Model with Subscriber-Controlled Wallet (was: SP 800-63-3)
All changes in this version
Title changed
Before · SP 800-63-3
SP 800-63-3
After · SP 800-63-4
SPFederated 800-63-3Digital Identity Model with Subscriber-Controlled Wallet
Control changed
Before · SP 800-63-3
NIST SP 800-63-3 is a substantial update and restructuring of SP 800-63-2. SP 800-63-3 introduces individual components of digital authentication assurance — AAL, IAL, and FAL — to support the growing need for independent treatment of authentication strength and confidence in an individual’s claimed identity (e.g., in strong pseudonymous authentication). A risk assessment methodology and its application to IAL, AAL, and FAL has been included in this guideline. It also moves the whole of digital identity guidance covered under SP 800-63 from a single document describing authentication to a suite of four documents (to separately address the individual components mentioned above) of which SP 800-63-3 is the top-level document.
Other areas updated in 800-63-3 include:
• Renamed to “Digital Identity Guidelines” to properly represent the scope includes identity proofing and federation, and to support expanding the scope to include device identity, or machine-to-machine authentication in future revisions.
• Terminology changes, including the use of authenticator in place of token to avoid conflicting use of the word token in assertion technologies.
• Updates to authentication and assertion requirements to reflect advances in both security technology and threats.
• Requirements on the storage of long-term secrets by verifiers.
• Restructured identity proofing model.
• Updated requirements regarding remote identity proofing.
• Clarification on the use of independent channels and devices as “something you have”.
• Removal of pre-registered knowledge tokens (authenticators), with the recognition that they are special cases of (often very weak) passwords.
• Requirements regarding account recovery in the event of loss or theft of an authenticator.
• Removal of email as a valid channel for out-of-band authenticators.
• Expanded discussion of re-authentication and session management.
• Expanded discussion of identity federation; restructuring of assertions in the context of federation.
After · SP 800-63-4
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• (Step 1: An applicant applies to separatelya addressCSP theidentity individualproofing componentsand mentionedenrollment above)process.
• ofStep which2: SPUpon 800-63-3successful identity proofing, the applicant goes through an onboarding process and is enrolled in the top-levelidentity documentservice as a subscriber.Other• areasStep updated3: The subscriber-controlled wallet is onboarded by the CSP, allowing the wallet to act in 800-63-3the include:role of IdP in later steps.•– RenamedThe subscriber authenticates to “the CSP’s issuance functionality by authenticating to the subscriber account or completes an abbreviated proofing process to demonstrate that they are the same user represented by the subscriber account. Fig. 5. Federated Digital Identity Guidelines”Model towith properlySubscriber-Controlled representWallet Example
– Subject RP Subject Roles Applicant
Claimant Subscriber 1
2 5 4 7
Identity Proofing and Enrollment
Onboarding Process Federation Request
Activation / Authentication Authenticated Session
Federation Protocol 6
Subscriber- Controlled Wallet Attribute Bundle Issuance 3
CSP
The subscriber activates the scopesubscriber-controlled includeswallet identityusing proofingan activation factor.
– The wallet generates or chooses a signing key and federationcorresponding verification key, andincluding toproof supportof expandinga key held by the scopewallet.
– toThe CSP creates one or more attribute bundles that include devicesubscriber identity,attributes and the wallet’s verification key (or machine-to-machinea authenticationreference into futurethat revisionskey).
•
– TerminologyThe changes,CSP includingissues the useattribute ofbundle authenticatorwith incorresponding placeverification ofkey tokeninto the subscriber-controlled wallet.
Other protocols and specifications often refer to avoidattribute conflictingbundles as credentials . These guidelines use ofthe term credentials to refer to a different concept. To avoid a conflict, the wordterm tokenattribute bundle is used within these guidelines. Normative requirements for attribute bundles can be found in assertionSec. technologies3.
•Updatesof to[SP800-63C]. authenticationThe andusual assertionsequence requirementsof interactions involved in providing an assertion to reflectthe advancesRP infrom botha securitysubscriber-controlled technologywallet andis threats.as follows:
• RequirementsStep on4: The RP requests that the storageclaimant ofauthenticate. long-termThis secretstriggers bya verifiersrequest for federated authentication to the wallet.
• RestructuredStep identity5: proofingThe modelclaimant proves possession and control of the subscriber-controlled wallet.
•
– UpdatedThe requirementsclaimant regardingactivates remotethe identitywallet proofingusing an activation factor or authenticates to a hosted service if the subscriber-controlled wallet is hosted by a service provider.
•
– ClarificationThe onwallet prepares an assertion that includes the useattribute ofbundle independentprovided channelsby andthe devicesCSP asfor “somethingthe yousubscriber have”account.
• RemovalStep of6: pre-registeredThe knowledgeRP tokensand (authenticators),the withwallet communicate through a federation protocol. The wallet provides an assertion, the recognitionCSP-signed thatattribute theybundles areand specialoptional casesadditional ofattributes (oftento verythe weak)RP passwordsthrough a federation protocol.
•RequirementsThe regardingRP accountverifies recoverythe assertion to establish confidence in the eventidentity and attributes of lossa orsubscriber theftfor ofaccess to an authenticator.online
•Removalservice ofat emailthe asRP. RPs use a validsubscriber’s channelfederated foridentity out-of-band(pseudonymous authenticators.or
•Expandednon-pseudonymous), discussionIAL, ofAAL, re-authenticationFAL, and sessionother managementfactors to make authorization decisions.
• Expanded discussionStep of7: identityAn federation;authenticated restructuringsession ofis assertionsestablished inbetween the contextsubscriber ofand federationthe RP.