LDAPWiki: Authenticator Assurance Levels

Overview#

Authenticator Assurance Levels (AAL also seen as Authentication Assurance Levels) is intended to provide some confidence in the Authentication provided by Identity Provider (IDP) to a Relying Party at some desired Level Of AssuranceAuthenticator Assurance Levels is a factor within Risk Assessment

Authenticator Assurance Levels is discussed in NIST.SP.800-63B and

LEVEL	Description
AAL1	Provides some assurance that the claimant controls the Claim requires at least single-factor authentication.
AAL2	Provides high confidence that the claimant controls Claim two different Authentication Factors (Multi-Factor Authentication) are required approved cryptographic techniques are required.
AAL3	Provides very high confidence that the claimant controls the Claim authentication based on Proof-of-Possession of a key through a cryptographic protocol requires a “hard” cryptographic authenticator.

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