IDENTIFICATION

Identification and Authentication(I&A) is the process of verifying that an identity is bound to the entity that makes an assertion or claim of identity. The I&A process assumes that there was an initial validation of the identity, commonly called identity proofing. Various methods of identity proofing are available, ranging from in-person validation using government issued identification, to anonymous methods that allow the claimant to remain anonymous, but known to the system if they return. The method used for identity proofing and validation should provide an assurance level commensurate with the intended use of the identity within the system. Subsequently, the entity asserts an identity together with an authenticator as a means for validation. The only requirements for the identifier is that it must be unique within its security domain.
Authenticators are commonly based on at least one of the following four factors:

Something you know,such as a password or a personal identification number (PIN). This assumes that only the owner of the account knows the password or PIN needed to access the account.
Something you have, such as a smart card or security token. This assumes that only the owner of the account has the necessary smart card or token needed to unlock the account.
Something you are,such as fingerprint, voice, retina, or iris characteristics.
Where you are, for example inside or outside a company firewall, or proximity of login location to a personal GPS device

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