Brocade Communications Systems Brocate Ethernet Access Switch 6910 - Manual (Page 937)

Brocade 6910 Ethernet Access Switch Configuration Guide 887
53-1002581-01
Configuring 802.1X Port Authentication
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FIGURE 219 Configuring Port Security
Configuring 802.1X Port Authentication
The IEEE 802.1X (dot1X) standard defines a port-based access control procedure that prevents
unauthorized access to a network by requiring users to first submit credentials for authentication.
Access to all switch 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 encryption method used to pass
authentication messages can be MD5 (Message-Digest 5), TLS (Transport Layer Security), PEAP
(Protected Extensible Authentication Protocol), or TTLS (Tunneled Transport Layer Security). 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,
non-EAP traffic on the port is blocked or assigned to a guest VLAN based on the “intrusion-action”
setting. In “multi-host” mode, only one host connected to a port needs to pass authentication for all
other hosts to be granted network access. Similarly, a port can become unauthorized for all hosts if
one attached host fails re-authentication or sends an EAPOL logoff message.