09-23-2008 08:00 AM
Network access control (NAC) aims to unify endpoint security, system authentication, and security enforcement in a more intelligent network access solution than simple firewalls. NAC ensures that every workstation accessing the network conforms to a security policy and can take remedial actions on workstations if necessary. For example, NACs can check if a workstation has antivirus software installed and, if not, NAC will limit the workstation's access to the network. In some cases, if NAC is capable of remedial measures, it can force-install an antivirus program on the workstation so that it will conform to the security policy. Although NAC can improve the security of your environment, most commercial NACs cost several thousand dollars. However, using NAC does not need to be that expensive.
PacketFence, a free open source NAC application, gives you the security of NAC for free.
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