Security Measures
173
Instruction Manual - NXA-ENET8-POE+
Perform these steps to configure port security:
1.
Click
Security
>
Port Security
.
2.
Mark the check box in the Security Status column to enable security, set the action to take when an invalid address is detected
on a port, and set the maximum number of MAC addresses allowed on the port.
3.
Click
Apply
.
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 (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 Message-Digest 5 (MD5), Transport Layer Security (TLS), Protected Extensible Authentication Protocol (PEAP), or
Tunneled Transport Layer Security (TTLS). 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 log off message.
MAC Filter ID
The identifier for a MAC address filter.
Last Intrusion MAC
The last unauthorized MAC address detected.
Last Time Detected Intrusion MAC
The last time an unauthorized MAC address was detected.
FIG. 203
Configuring Port Security
FIG. 204
Configuring Port Authentication
Security - Port Security Options
802.1x
client
RADIUS
server
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.