PPP EAP TLS Authentication Protocol (RFC2716)
Original Publication Date: 1999-Oct-01
Included in the Prior Art Database: 2019-Feb-10
Internet Society Requests For Comment (RFCs)
B. Aboba: AUTHOR [+1]
The Point-to-Point Protocol (PPP) provides a standard method for transporting multi-protocol datagrams over point-to-point links.The Extensible Authentication Protocol (EAP) is a PPP extension that provides support for additional authentication methods within PPP. This memo defines an Experimental Protocol for the Internet community.
Network Working Group B. Aboba Requests for Commments: 2716 D. Simon Category: Experimental Microsoft October 1999
PPP EAP TLS Authentication Protocol
Status of this Memo
This memo defines an Experimental Protocol for the Internet community. It does not specify an Internet standard of any kind. Discussion and suggestions for improvement are requested. Distribution of this memo is unlimited.
Copyright (C) The Internet Society (1999). All Rights Reserved.
The Point-to-Point Protocol (PPP) provides a standard method for transporting multi-protocol datagrams over point-to-point links. PPP also defines an extensible Link Control Protocol (LCP), which can be used to negotiate authentication methods, as well as an Encryption Control Protocol (ECP), used to negotiate data encryption over PPP links, and a Compression Control Protocol (CCP), used to negotiate compression methods. The Extensible Authentication Protocol (EAP) is a PPP extension that provides support for additional authentication methods within PPP.
Transport Level Security (TLS) provides for mutual authentication, integrity-protected ciphersuite negotiation and key exchange between two endpoints. This document describes how EAP-TLS, which includes support for fragmentation and reassembly, provides for these TLS mechanisms within EAP.
The Extensible Authentication Protocol (EAP), described in , provides a standard mechanism for support of additional authentication methods within PPP. Through the use of EAP, support for a number of authentication schemes may be added, including smart cards, Kerberos, Public Key, One Time Passwords, and others. To date however, EAP methods such as  have focussed on authenticating a client to a server.
Aboba & Simon Experimental [Page 1]
RFC 2716 PPP EAP TLS Authentication Protocol October 1999
However, it may be desirable to support mutual authentication, and since PPP encryption protocols such as  and  assume existence of a session key, it is useful to have a mechanism for session key establishment. Since design of secure key management protocols is non-trivial, it is desirable to avoid creating new mechanisms for this. The EAP protocol described in this document allows a PPP peer to take advantage of the protected ciphersuite negotiation, mutual authentication and key management capabilities of the TLS protocol, described in .
2.1. Requirements language
In this document, the key words "MAY", "MUST, "MUST NOT", "optional", "recommended", "SHOULD", and "SHOULD NOT", are to be interpreted as described in .
3. Protocol overview
3.1. Overview of the EAP-TLS conversation
As described in , the EAP-TLS conversation will typically begin with the authenticator and the peer negotiating EAP. The authenticator will then typically send an EAP-Request/Identity packet to the peer, and the peer will respond with an EAP-Response/Identity packet to the authenticator, containing the peer’s userId.