Modelling network to assess security properties

• US 20070136788A1
• Filed: 12/14/2005
• Published: 06/14/2007
• Est. Priority Date: 12/16/2004
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Inventors: Baldwin, Adrian, Monahan, Brian, Shiu, Simon
• Granted Patent: US 9,083,748 B2
• Time in Patent Office: Days
• US Class Current: 726/3
• CPC Class Codes: H04L 63/20 for managing network security; network security policies in general filtering policies H04L63/0227

Abstract

A method of assessing a network uses a model (450) having nodes (100, 110) to represent parts of the network infrastructure and the application services, and having links to represent how the nodes influence each other. Dependencies or effects of the application services are found by determining paths through the nodes and links of the model (530). Such assessment can be useful for design, test, operations, and diagnosis, and for assessment of which parts of the infrastructure are critical to given services, or which services are dependent on, or could have an effect on a given part of the infrastructure. The dependencies or effects can encompass reachability information. The use of a model having links and nodes can enable more efficient processing, to enable larger or richer models. What changes in the dependencies or effects result from a given change in the network can be determined (830).

Claims

1. A method of using a data model of a network infrastructure, the model having nodes to represent parts of the network infrastructure, and having links to represent how the nodes influence each other, and the method having the steps of making a representation in the model of one or more alterations in the network infrastructure, and automatically deriving from the model either:

changes in security properties of the network infrastructure resulting from the alteration;

or

alterations in the network infrastructure which can enable a given change in the security properties.

2. The method of claim 1, having the step of determining paths through the nodes and links of the model.

3. The method of claim 1, the model having a representation of application services arranged to use the network infrastructure, and the method having the step of deriving changes in the security properties resulting from a given alteration in the network infrastructure or in the application services.

4. The method of claim 1 having the steps of using the model to assess candidate alterations to the network infrastructure or application services to enable a given security property.

5. The method of claim 1, having the steps of determining the security properties before making the representation of the alterations in the model, then repeating the determining of the security properties, and comparing these properties to derive the changes.

6. The method of claim 1, the step of making the representation of the alterations having the steps of creating at least a second instance of the model, having a representation of one or more candidate alterations, and the step of deriving the changes having the steps of determining the security properties from the instances, then comparing these properties.

7. The method of claim 1, the security properties comprising any of the following;

what parts of the network are reachable from a given point or part of the network with an existing configuration, what parts of the network are reachable from a given point or part of the network if the configuration is altered, what security controls exist between given points or regions of the network, and what security controls exist in new paths created between given points or regions of the network if the configuration is altered.

8. The method of claim 1, the model comprising a database of object oriented elements representing the nodes, and the method having the step of searching the database for logical paths through the model, which match given constraints.

9. The method of claim 8, the database having object oriented elements representing the links.

10. The method of claim 8, having the step of creating an object representing at least one logical path through two or more links of the model.

11. The method of claim 8, the searching comprising making a recursive query of the database.

12. The method of claim 8 and having any of the steps of:

receiving and classifying information about the network infrastructure or application services, to add to the model, and normalizing a path query with reference to class definitions of the model.

13. A computer program arranged to carry out the method of claim 1 of using a model.

14. A network having a network infrastructure, and the computer program of claim 13 for using the data model.

15. A method of using a data model of a network infrastructure and application services arranged to use the network infrastructure, the model having nodes to represent parts of the network infrastructure and the application services, and having links to represent how the nodes influence each other, and the method having the steps of finding paths through the nodes and links of the model, and automatically deriving security properties of at least the application services from the determined paths.

16. The method of claim 15, having the steps of using the model to derive changes in the security properties resulting from a given alteration in either the network infrastructure or the application services.

17. The method of claim 16, the step of deriving the changes in the security properties having the steps of determining the security properties before making a representation in the model of the given alterations in either the network infrastructure or the application services, then repeating the determining of security properties, and comparing these properties.

18. The method of claim 15, the security properties comprising any of the following;

what parts or regions of the network infrastructure or application services are reachable from a given point or part of the network infrastructure or application services with an existing configuration, what parts or regions are reachable if the configuration is altered, what security controls exist between given points or regions, what security controls exist in new paths created between given points or regions if the configuration is altered, reachability of a given application service, and effect of a given application service on reachability of other parts.

19. The method of claim 15, the model having an indication of criticality of a node or link to a given one or more of the application services, and the step of determining security properties comprising any of;

determining which nodes or links to include in a search of the model, according to the indication of criticality, determining which nodes and links in the model can be affected by a given one or more of the application services, and sorting the security properties according to the indication of criticality.

20. The method of claim 15, the model comprising a database of object oriented elements representing the nodes, and the method having the step of searching the database for logical paths through the model, which match given constraints.

21. The method of claim 20, the database having object oriented elements representing the links.

22. The method of claim 20, having the step of creating an object representing at least one logical path through two or more links of the model.

23. The method of claim 20, the searching comprising making a recursive query of the database.

24. The method of claim 20 and having any of the steps of:

receiving and classifying information about the network infrastructure or application services, to add to the model, and normalizing a path query with reference to class definitions of the model.

25. A computer program arranged to carry out the method of claim 15.

26. A network having a network infrastructure and application level services, and the computer program of claim 26.

27. A database having a model of at least some of a network, the model having nodes to represent parts of the network infrastructure and the application services, and having links to represent how the nodes influence each other, arranged such that dependencies or effects of the application services can be determined from paths through the nodes and links of the model.

28. A method of using a data model of a network infrastructure or application services, the model having nodes to represent parts of the network infrastructure and application services, and having links to represent how the nodes influence each other, at least the links being represented by object oriented elements and the method having the steps of determining paths through the nodes and links of the model, and deriving security properties of the network infrastructure or application services from the paths.

29. A network substantially as described herein with reference to the figures.