E-authentication | Tokens

Therefore, a token used for E-authentication must be protected. The token, for example, may be a piece of hardware (the token) which contains a cryptographic key (the token secret);

the key is protected by encrypting it with a password. When used, the cryptographic key produces an output (the authenticator) which is used in the authentication process to authenticate the Claimant. An impostor must steal the encrypted key (by stealing the hardware) and learn the password to use the token.

Authentication systems are often categorized by the number of factors that they incorporate. The three factors often considered as the cornerstone of authentication are:

-Something you know (for example, a password)

-Something you have (for example, an ID badge or a cryptographic key)

-Something you are (for example, a thumb print or other biometric data)

Authentication systems that incorporate all three factors are stronger than systems that only incorporate one or two of the factors.

The system may be implemented so that multiple factors are presented to the Verifier, or some factors may be used to protect a secret that will be presented to the Verifier.

For example, consider a hardware device that holds a cryptographic key. The key might be activated by a password or the hardware device might include a biometric capture device and uses a biometric to activate the key.

Such a device is considered to effectively provide two factor authentication, although the actual authentication protocol between the Verifier and the Claimant simply proves possession of the key.

The secrets are often based on either public key pairs (asymmetric keys) or shared secrets. A public key and a related private key comprise a public key pair. The private key is used by the Claimant as a token.

A Verifier, knowing the Claimant's public key through some credential (typically a public key certificate), can use an authentication protocol to verify the Claimant's identity, by proving that the Claimant has control of the associated private key token (Proof of Possession).

Shared secrets are either symmetric keys or passwords. In a protocol sense, all shared secrets are similar, and can be used in similar authentication protocols; however, passwords, since they are often committed to memory, are something the Claimant knows, rather than something he or she has.

Passwords, because they are committed to memory, usually do not have as many possible values as cryptographic keys, and, in many protocols, are vulnerable to network attacks that are impractical for keys. Moreover the entry of passwords into systems (usually through a keyboard) presents the opportunity for very simple keyboard logging or "shoulder surfing" attacks.

Therefore keys and passwords demonstrate somewhat separate authentication properties (something you know rather than something you have). Passwords often have lesser resistance to network attacks. However, when using either public key pairs or shared secrets, the Subscriber has a duty to maintain exclusive control of his or her token, since possession and control of the token is used to authenticate the Claimant's identity.

Biometrics are unique personal attributes that can be used to verify the identity of a person who is physically present at the point of verification. They include facial features, fingerprints, DNA, iris and retina scans, voiceprints and many other characteristics.

This publication recommends that biometrics be used in the registration process to later prevent a Subscriber who is in fact registered from repudiating the registration, to help identify those who commit registration fraud, and to unlock tokens.

Biometric characteristics are not recommended for use directly as tokens in this document.

Development of a Cryptographic Module
Cryptographic Module | Vendor Testing | Delivery and Operation
Cryptographic Module Guidance
Cryptographic Module Finite State Model
Cryptographic Modules - Design
Cryptography - Configuration Management
Cryptography - Conditional Self-Tests
Cryptography - Pre-Operational Self-Test
Cryptography - SSP Zeroization
Cryptography - SSP Entry and Output
Cryptography - Environmental Failure Testing Procedures
Multiple-Chip Standalone Cryptographic Modules
Multiple-Chip Embedded Cryptographic Modules
Single-Chip Cryptographic Modules
Cryptography - General Physical Security Requirements
Cryptographic Module - Physical Security
Cryptography - Operating System Requirements for Modifiable Operational Environments
Cryptographic Module - Operational Environment
Cryptographic Module - Software
Cryptographic Module - Services
Cryptographic Module - Operator Authentication
Cryptographic Module - LOGICAL INTERFACES
Cryptographic Module Specification
Cryptography - Acronyms