System information

SIGNAMAX a.s.
Seat: Palackeho trida 38, 612 00 Brno, CZ l Office: Vlarska 22, P. O. Box 214, 658 14 Brno, CZ
T:[phone] l F:[phone] l www.signamax.eu
148
The overview of operation flow for the Fig. 3-53 is quite simple. When Supplicant
PAE issues a request to Authenticator PAE, Authenticator and Supplicant
exchanges authentication message. Then, Authenticator passes the request to
RADIUS server to verify. Finally, RADIUS server replies if the request is granted or
denied.
While in the authentication process, the message packets, encapsulated by
Extensible Authentication Protocol over LAN (EAPOL), are exchanged
between an authenticator PAE and a supplicant PAE. The Authenticator
exchanges the message to authentication server using EAP encapsulation. Before
successfully authenticating, the supplicant can only touch the authenticator to
perform authentication message exchange or access the network from the
uncontrolled port.
Fig. 3-53
In the Fig. 3-54, this is the typical configuration, a single supplicant, an authenticator
and an authentication server. B and C is in the internal network, D is Authentication server
running RADIUS, switch at the central location acts Authenticator connecting to PC A and A is
a PC outside the controlled port, running Supplicant PAE. In this case, PC A wants to access
the services on device B and C, first, it must exchange the authentication message with the
authenticator on the port it connected via EAPOL packet. The authenticator transfers the
supplicant’s credentials to Authentication server for verification. If success, the authentication
server will notice the authenticator the grant. PC A, then, is allowed to access B and C via the
switch. If there are two switches directly connected together instead of single one, for the link
connecting two switches, it may have to act two port roles at the end of the link: authenticator
and supplicant, because the traffic is bi-directional.
LAN
A
uthenticato
r
PAE
Services Offered
by Authenticator
(e.g Bridge Relay)
Authenticator’s System
Authentication
Server’s System
A
uthentication
Server
Supplicant
PAE
Supplicant’s
System
Uncontrolled portControlled port
MAC Enable
Port Authorize