Using Secure Coprocessors to Protect Access to Enterprise Networks

Enterprise firewalls can be easily circumvented, e.g. by attack agents aboard infected mobile computers or telecommuters' computers, or by attackers exploiting rogue access points or modems. Techniques that prevent connection to enterprise networks of nodes whose configuration does not conform to enterprise policies could greatly reduce such vulnerabilities. Network Admission Control (NAC) and Network Access Protection (NAP) are recent industrial initiatives to achieve such policy enforcement. However, as currently specified, NAC and NAP assume that users are not malicious. We propose novel techniques using secure coprocessors to protect access to enterprise networks. Experiments demonstrate that the proposed techniques are effective against malicious users and have acceptable overhead.