SMC Networks SMC6724L3 Management Manual page 81

ports in a network can be centrally controlled from a server, which means
that authorized users can use the same credentials for authentication from
any point within the network.
This switch uses
the Extensible
Authentication
Protocol over LANs
(EAPOL) to exchange
authentication
protocol messages
with the client, and
a remote RADIUS
authentication server
to verify user identity and access rights. When a client (i.e., Supplicant)
connects to a switch port, the switch (i.e., Authenticator) responds with an
EAPOL identity request. The client provides its identity (such as a user
name) in an EAPOL response to the switch, which it forwards to the
RADIUS server. The RADIUS server verifies the client identity and sends
an access challenge back to the client. The EAP packet from the RADIUS
server contains not only the challenge, but the authentication method to be
used. The client can reject the authentication method and request another,
depending on the configuration of the client software and the RADIUS
server. The authentication method can be MD5, TLS (Transport Layer
Security), TTLS (Tunneled Transport Layer Security), or other. The client
responds to the appropriate method with its credentials, such as a
password or certificate. The RADIUS server verifies the client credentials
and responds with an accept or reject packet. If authentication is
successful, the switch allows the client to access the network. Otherwise,
network access is denied and the port remains blocked.
The operation of dot1x on the switch requires the following:
• The switch must have an IP address assigned.
• RADIUS authentication must be enabled on the switch and the IP
address of the RADIUS server specified.
802.1x
client
RADIUS
server
U A
SER UTHENTICATION
1. Client attempts to access a switch port.
2. Switch sends client an identity request.
3. Client sends back identity information.
4. Switch forwards this to authentication server.
5. Authentication server challenges client.
6. Client responds with proper credentials.
7. Authentication server approves access.
8. Switch grants client access to this port.
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