PT-7728 User’s Manual
Featured Functions
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Using Port Access Control
The PT-7728 provides two kinds of Port-Base Access Control. One is Static Port Lock and the
other is IEEE 802.1X.
Static Port Lock
The PT-7728 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 hackers 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 PT-7728 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 PT-7728 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.
Configuring Static Port Lock
The PT-7728 supports adding unicast groups manually if required.
