CANOGA PERKINS CanogaOS Configuration Guide - Manual (Page 311)

CanogaOS Configuration Guide
Proprietary & Confidential Canoga Perkins Metro Ethernet Switches Page 311 of 350
When the switch receives frames from the authentication server, the server’s frame header is
removed, leaving the EAP frame, which is then encapsulated for Ethernet and sent to the client.
Port Access Entity (PAE)
The Port Access Entity (PAE) operates the Algorithms and Protocols associated with the
authentication mechanisms for a given Port of the System.
The Authenticator PAE controls the authorized/unauthorized state of its controlled Port
depending on the outcome of the authentication process.
Unidirectional and Bidirectional control
In the unauthorized state, the port can be set as unidirectional control or bidirectional control.
In bidirectional state, the port does not allowed packet sending or receiving, while in the
unidirectional state, the port only discards incoming traffic.
38.1.3 Authentication Initiation and Message Exchange
The switch or the client can initiate authentication. If you enable authentication on a port by
using the dot1x port-control auto interface configuration command, the switch initiates
authentication when the link state changes from down to up or periodically as long as the port
remains up and unauthenticated. The switch sends an EAP-request/identity frame to the client to
request its identity. Upon receipt of the frame, the client responds with an EAP-response/identity
frame.
However, if during boot-up, the client does not receive an EAP-request/identity frame from the
switch, the client can initiate authentication by sending an EAPOL-start frame, which prompts
the switch to request the client identity.
When the client supplies its identity, the switch begins its role as the intermediary, passing EAP
frames between the client and the authentication server until authentication succeeds or fails. If
the authentication succeeds, the switch port becomes authorized.
The following figure shows a message exchange initiated by the client using the
One-Time-Password (OTP) authentication method with a RADIUS server.