xStack DGS-3400 Series Layer 2 Gigabit Ethernet Managed Switch 
Port-Based Network Access Control 
…
802.1X
Client
802.1X
Client
802.1X
Client
802.1X
Client
802.1X
Client
802.1X
Client
802.1X
Client
802.1X
Client
802.1X
Client
Network access controlled port
Network access uncontrolled port
RADIUS
Server
Ethernet Switch
 
Figure 10- 11.  Example of Typical Port-Based Configuration 
Once the connected device has successfully been authenticated, the Port then becomes Authorized, and all subsequent traffic on 
the Port is not subject to access control restriction until an event occurs that causes the Port to become Unauthorized. Hence, if the 
Port is actually connected to a shared media LAN segment with more than one attached device, successfully authenticating one of 
the attached devices effectively provides access to the LAN for all devices on the shared segment. Clearly, the security offered in 
this situation is open to attack. 
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