3com DUA1550-0AAA02 User Manual

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Case Study 2 - Restricting Network Access To Known Computers
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Click OK and exit the Active Directory Users and Computers interface.
On being informed that a specific PC needs to be denied access to the 
network, use the Active Directory Users and Computers interface to 
perform the following:
Either:
click on Computers in the Tree pane, or
if Organizational Units have been created, click on the organizational 
units subfolders until you reach the desired unit holding the PC.
Highlight the specific PC in the Details pane, and right-click. Select 
Properties.
Select the Network Access tab from the Properties dialog window.
A list of rules that the operator has permission to apply will be displayed
Tick the Unauthorized Computers rule.
Click OK and exit the Active Directory Users and Computers interface.
What Happens
The following takes place when a device connects to the network.
The PC connects to the network
The switch sends the MAC address of the PC via RADIUS to IAS
If the PC is listed in Active Directory, and the Authorized Computers 
rule has been applied to the PC, IAS replies Accept and the switch 
enables the port.
If the PC is listed in Active Directory, but either the Default Rule or the 
Unauthorized Computers rule is applied to the PC, IAS replies Reject 
and the switch disables the port.
If the PC is not listed in Active Directory, IAS replies Reject and the 
switch disables the port.