Analysis of Integrity Policies using Soft Constraints

An integrity policy defines the situations when modification of information is authorized and is enforced by the security mechanisms of the system. However, in a complex application system it is possible that an integrity policy may have been incorrectly specified and, as a result, a user may be authorized to modify information that can lead to an unexpected system compromise. In this paper we outline a scalable and quantitative technique that uses constraint solving to model and analyze the effectiveness of application system integrity policie

Managing Security in Dynamic Networks

This paper describes our initial steps towards self-configuring mechanisms for automating high-level security and service policies in dynamic networks. We build on the NESTOR system developed at Columbia University for instrumenting and monitoring constraints on network elements and services such as DHCP, DNS zones, host-based access controls, firewalls, and VLAN switches. Current paradigms for configuration management require that changes be propagated either manually or via low-level scripts suited to static networks. Our longer-term goal is to provide fully automated techniques which work for dynamic networks in which changes are frequent and often unanticipated. Automated approaches, such as ours, are the only viable solution for global and dynamic networks and services. In this paper, we focus on one specific scenario to illustrate our ideas: providing transparent and secure access to selected services from a mobile laptop. The challenge is that reconfiguration must satisfy the security policies of two independent corporate networks

Managing Security in Dynamic Networks

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