The Protected Extensible Authentication Protocol is a protocol that encapsulates the Extensible Authentication Protocol (EAP) within an encrypted and authenticated Transport Layer Security (TLS) tunnel.

The Protected Extensible Authentication Protocol is a protocol that encapsulates the Extensible Authentication Protocol (EAP) within an encrypted and authenticated Transport Layer Security (TLS) tunnel.

Currently there are two standards:

  • PEAPv0/EAP-MSCHAPv2 (PEAPv0/EAP-MSCHAPv2 is the most common form of PEAP in use, and what is usually referred to as PEAP. The inner authentication protocol is Microsoft's Challenge Handshake Authentication Protocol, meaning it allows authentication to databases that support the MS-CHAPv2 format, including Microsoft NT and Microsoft Active Directory.)
  • PEAPv1/EAP-GTC (PEAPv1/EAP-GTC was created by Cisco to provide interoperability with existing token card and directory based authentication systems via a protected channel and is not supported by the Microsoft Windows Operating System natively.)

Read more here: http://en.wikipedia.org/wiki/Protected_Extensible_Authentication_Protocol