• abstract:
  • 1.
    Pre-Boot Authentication (PBA) or Power-On Authentication (POA) serves as an extension of the BIOS or boot firmware and guarantees a secure, tamper-proof environment external to the operating system as a trusted authentication layer. The PBA prevents anything being read from the hard disk such as the operating system until the user has confirmed he/she has the correct password or other credentials.

以上来源于: Wikipedia