EDS-510A Series User’s Manual
Featured Functions
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Using Port Access Control
The EDS-510A provides two kinds of Port-Based Access Controls. One is Static Port Lock and the
other is IEEE 802.1X.
Static Port Lock
The EDS-510A can also be configured to protect static MAC addresses for a specific port. With
the Port Lock function, these locked ports will not learn any additional addresses, but only allow
traffic from preset static MAC addresses, helping to block crackers and careless usage.
IEEE 802.1X
The IEEE 802.1X standard defines a protocol for client/server-based access control and
authentication. The protocol restricts unauthorized clients from connecting to a LAN through ports
that are open to the Internet, and which otherwise would be readily accessible. The purpose of the
authentication server is to check each client that requests access to the port. The client is only
allowed access to the port if the client’s permission is authenticated.
The IEEE 802.1X Concept
Three components are used to create an authentication mechanism based on 802.1X standards:
Client/Supplicant, Authentication Server, and Authenticator.
Supplicant:
The end station that requests access to the LAN and switch services and responds to
the requests from the switch.
Authentication server:
The server that performs the actual authentication of the supplicant.
Authenticator:
Edge switch or wireless access point that acts as a proxy between the supplicant
and the authentication server, requesting identity information from the supplicant, verifying the
information with the authentication server, and relaying a response to the supplicant.
The EDS-510A acts as an authenticator in the 802.1X environment. A supplicant and an
authenticator exchange EAPOL (Extensible Authentication Protocol over LAN) frames with each
other. We can either use an external RADIUS server as the authentication server, or implement the
authentication server in the EDS-510A by using a Local User Database as the authentication
look-up table. When we use an external RADIUS server as the authentication server, the
authenticator and the authentication server exchange EAP frames between each other.
Authentication can be initiated either by the supplicant or the authenticator. When the supplicant
initiates the authentication process, it sends an “EAPOL-Start” frame to the authenticator. When
the authenticator initiates the authentication process or when it receives an “EAPOL Start” frame,
it sends an “EAP Request/Identity” frame to ask for the username of the supplicant. The following
actions are described below:
