Method and apparatus for verifying the integrity and security of computer networks and implementation of counter measures

• US 7,168,093 B2
• Filed: 01/25/2001
• Issued: 01/23/2007
• Est. Priority Date: 01/25/2001
• Status: Expired due to Term

• Current Assignee: NTT Security (US) Inc. (Nippon Telegraph and Telephone Corporation)
• Original Assignee: Solutionary, Inc (Nippon Telegraph and Telephone Corporation)
• Inventors: Hrabik, Michael, Guilfoyle, Jeffrey J., Beaver, Edward Mac
• Primary Examiner(s): Revak; Christopher
• Assistant Examiner(s): Jackson; Jenise E.
• Application Number:
  US09/770,525
• Publication Number:
  US 20020099958A1
• Time in Patent Office: 2,189 Days
• Field of Search: 713200-201, 709208-209, 709223-229, 714/14, 714/15, 726/22, 726/23, 726/24, 726/25
• US Class Current: 726/22
• CPC Class Codes: H04L 63/1416 Event detection, e.g. attack signature detection
• CPC Class Codes: H04L 63/1433 Vulnerability analysis
• CPC Class Codes: H04L 63/20 for managing network security; network security policies in general filtering policies H04L63/0227

Abstract

A method and apparatus for verifying the integrity of devices on a target network having two components: a subsystem connected to the target network, and a master system, isolated therefrom by a secure link. The topological and hierarchical relationship of the of the devices to each other improves stability of the apparatus. Random testing of target network devices by the subsystem and random testing of the subsystem by the master system provide verification and independent self-checking.

Claims

1. A security system for a computer network, the network having a plurality of devices connected thereto, at least some of the devices having security-related functions, the security system comprising:

(a) a security subsystem associated with at least some of the devices in the network which tests the integrity of the security-related functions;

(b) a master system which monitors the integrity of the security subsystem and receives and stores results of the integrity testing of the devices having security-related functions; and

(c) a secure link connected between the security subsystem and the master system, the master system monitoring the integrity of the security subsystem and receiving the results of the integrity testing of the devices having security-related functions through the first secure link, wherein one of the master system and the security subsystem further monitors whether a device having security-related functions responds to said one of the master system and the security subsystem, and wherein one of the security subsystem and the master system takes action when no response is detected.

2. The system of claim 1 wherein the security subsystem tests the integrity of the security-related functions by generating pseudo-attacks on the devices having security-related functions.

3. The system of claim 1 wherein the countermeasures include restricting or disabling access to the network or a device in the network.

4. The system of claim 1 wherein the master system further comprises a pseudo-attack generator which generates attacks on the network, the security subsystem detecting such attacks when functioning properly, the master system comparing the pseudo-attacks made on the network to the attacks actually detected by the subsystem, the master system thereby determining whether the integrity of the subsystem has been compromised.

5. The system of claim 1 wherein the secure link is defined by a virtual private network (VPN) tunnel.

6. The system of claim 1 wherein at least one of the devices having security-related functions is a firewall.

7. The system of claim 1 wherein at least one of the devices having security-related functions is a network intrusion detection system.

8. A security system for a computer network, the network having a plurality of devices connected thereto, the security system comprising:

(a) a security subsystem connected to at least some of the devices in the network, the security subsystem configured to monitor activities of the at least some devices on the network, and detect attacks on the at least some devices;

(b) a master system which monitors the integrity of the security subsystem and registers information pertaining to attacks detected by the security subsystem; and

(c) a first secure link connected between the security subsystem and the master system, the master system monitoring the integrity of the security subsystem and receiving the information pertaining to the attacks through the first secure link, wherein one of the master system and the security subsystem further monitors whether the device responds to one of the master system and the security subsystem, and wherein one of the security subsystem and the master system takes action when no response is detected.

9. A security system for a computer network, the network having a plurality of devices connected thereto, the security system comprising:

(a) a security subsystem connected to at least some of the devices in the network, the security subsystem configured to monitor activities of the at least some devices on the network and detect attacks on the at least some devices;

(b) a master system which monitors the integrity of the security subsystem and registers information pertaining to attacks detected by the security subsystem; and

(c) a first secure link connected between the security subsystem and the master system, the master system monitoring the integrity of the security subsystem and receiving the information pertaining to the attacks through the first secure link, wherein the master system further monitors whether the security subsystem responds to the master system, the master system taking action if no response is detected.

10. The system of claim 9 wherein the master system does not take direction from the security subsystem.

11. The system of claim 9 further comprising:

(d) a second secure link connected between the master system and the network which enables data communication from the master system to the network for issuing instructions to the network devices.

12. The system of claim 11 wherein the instructions are issued if the first secure link is severed or compromised.

13. The system of claim 9 wherein the master system is hierarchically independent from the security subsystem.

14. The system of claim 9 wherein the security subsystem is hierarchically subordinate to the master system.

15. The system of claim 9 wherein the first secure link is defined by a virtual private network (VPN) tunnel.

16. The system of claim 9 wherein the master system further comprises a pseudo-attack generator which generates attacks on the network, the security subsystem detecting such attack;

and sending expected replies to the master system when its integrity is intact, the master system detecting whether the expected replies are received in response to a pseudo-attack to determine whether the integrity of the subsystem has been compromised.