Hard Authentication Tokens


A hard authentication token is an authentication token generated by a cryptoprocessor on a dedicated hardware device.

  • authentication design means that there is no transmission of the token itself
  • Several device-based authenticators can be used to implement hard tokens:
    • smart cards
      • implement certificate-based authentication
      • stores:
        • user’s digital certificate
        • private key associated with the certificate
        • and a personal identification number (PIN) used to activate the card
      • must be presented to a reader
      • card types
        • physical contact
        • contactless near-field communication (NFC)
    • One-time password (OTP)
      • refers to a cryptoprocessor that can generate a token
      • does not need an interface to connect with a computer
        • user just reads the code displayed
    • Security key
      • refers to a portable hardware security module (HSM) with a computer interface
      • most closely associated with U2F,
        • some might also support certificate-based authentication or HOTP/TOTP
      • must be activated to show presence
      • Some keys just have an activation button, but most use a biometric fingerprint reader for better security
      • PIN must also be configured as a backup mechanism

Info

There are also simpler smart cards and fobs that simply transmit a static token programmed into the device.

  • For example, many building entry systems work on the basis of static codes
  • These mechanisms are highly vulnerable to cloning and replay attacks