Designing Access Controls

Choose Endpoint Integrity Testing Methods

Advantages and Disadvantages of ActiveX Testing

The ActiveX agent does not remain on the endpoint and does not require maintenance or upgrades—saving overhead. Generally, the NAC 800 can test an endpoint through its firewall, automatically opening the necessary ports.

However, while the NAC agent requires a one-time installation and user interaction, the ActiveX agent requires that interaction every time an endpoint connects. Although the user may not notice the installation if the endpoint allows ActiveX content without prompting, the installation does add overhead to network traffic.

Internet Explorer must be open for the NAC 800 to test the endpoint. If a user closes Internet Explorer after his or her endpoint has gained access, the NAC 800 cannot retest the endpoint. The user can continue to connect to the network—even if the endpoint becomes non-compliant—for as long as IE is closed.

Agentless

RPC was designed to provide a flexible framework for a variety of communications between remote devices. The NAC 800 uses RPC to run integrity checks on endpoints, which must support RPC.

In order for an endpoint to accept the RPC messages, the NAC 800 must submit credentials for an administrator of that endpoint. On the NAC 800, these credentials are called agentless credentials and can be:

Configured in cluster settings—Enter the credentials of an adminis- trator in the endpoint’s domain.

Submitted by the end-user—This option allows agentless testing of a user who is not a member of your domain. However, because users often do not know, or are reluctant to share, the proper credentials, this option is not generally recommended.

C a u t i o n

Never make agentless testing the only method available to test non-domain

 

members. Because you will not know the administrator credentials for these

 

endpoints, agentless testing will not succeed. Depending on your configura-

 

tion, the user will probably be placed in a test or quarantine VLAN.

 

 

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