on May 25th, 2007

Exactly what is NAC? Network access control is a combination of hardware and software technology that dynamically controls access to networks. It’s not a complete security solution in itself, but works in concert with other security systems to provide a more complete security environment. Here are answers to other frequently asked questions about the technology.

Related Articles:

• 5 Steps to NAC Deployment
• Network Access Control: Securing the Perimeter
• NAC Security: The New Hotness
• NAC Comparison Guide

How does NAC work?

NAC products continuously scan for computers and other devices that can connect to the network to see if they are compliant with enterprise security policies, allow or deny access and also provide for quarantining and remediation of any affected devices.

Where does NAC go?

NAC can be applied at the edge of the network, inside the network or at the endpoint itself as client software.

What is inline NAC?

An inline NAC appliance can be placed at various critical points on a network and combines all the elements of NAC – assessment, enforcement and remediation – in the one box to simplify things.

What’s out-of-band NAC?

Out-of-band NAC solutions sit outside of the network alongside such things as network switches and routers and take their cue from messages sent by the network device when new endpoints connect to the network, and access is granted or denied through the switch or router.

Who sells NAC solutions?

The main NAC architectural approaches are based on Cisco’s Network Admission Control, Microsoft’s Network Access Protection and the Trusted Computing Group’s Trusted Network Connect (TNG). Many network and security vendors have developed NAC solutions based on these.

Do they work with each other?

Not natively, but Cisco and Microsoft have partnered to develop an interoperable architecture that will allow Cisco’s NAC to work with Microsoft’s NAP. However there are no plans yet for any joint development of the architectures themselves.

What about TNG?

The Trusted Computing Group announced in May 2007 that TNC and NAP interoperate.

What is IETF NAC?

The Internet Engineering Task Force is working to standardize protocols that are common to the solutions proposed by Cisco, Microsoft and Trusted Computer Group, which will be the basis for a single NAC specification.

Related Stories:

5 Steps to NAC Deployment

Network Access Control: Securing the Perimeter

NAC Security: The New Hotness

NAC Comparison Guide