Specifications

User Authentication
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Configuring 802.1x Port Authentication
Network switches can provide open and easy access to network resources by
simply attaching a client PC. Although this automatic configuration and access is a
desirable feature, it also allows unauthorized personnel to easily intrude and
possibly gain access to sensitive network data.
The IEEE 802.1x standard defines a port-based access control procedure that
prevents unauthorized access to a network by requiring users to first enter a user ID
and password for authentication. Access to all switch ports in a network can be
centrally controlled from a server, which means that authorized users can use a
single user ID and password 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.
• Each switch port that will be used must be set to dot1x “Auto” mode.
• Each client that needs to be authenticated must have dot1x client software
installed and properly configured.
• The RADIUS server must support EAPOL and MD5, TLS or TTLS authentication.