802.1X Authentication Process; Figure 2-1:Authenticating A Port Using Eapol - Nortel Alteon OS 42C4911 Application Manual

802.1x Authentication Process

The clients and authenticators communicate using Extensible Authentication Protocol (EAP),
which was originally designed to run over PPP, and for which the IEEE 802.1x Standard has
defined an encapsulation method over Ethernet frames, called EAP over LAN (EAPOL).
Figure 2-1
802.1x Client
Figure 2-1 Authenticating a Port Using EAPoL
42C4911, January 2007
shows a typical message exchange initiated by the client.
EAPOL
Ethernet
Port Unauthorized
EAPOL-Start
EAP-Request (Credentials)
EAP-Response (Credentials)
EAP-Request (Credentials)
EAP-Response (Credentials)
EAP-Success
Port Authorized
GbESM RADIUS-EAP
(Authenticator)
(RADIUS Client)
Radius-Access-Request
Radius-Access-Challenge
Radius-Access-Request
Radius-Access-Accept
Chapter 2: Port-based Network Access Control
Alteon OS Application Guide
RADIUS
Server
UDP/IP
69