Protecting Security Policies in Ubiquitous Environments Using One-Way Functions

This paper addresses the problem of protecting security policies and other security-related information in security mechanisms, such as the detection policy of an Intrusion Detection System or the filtering policy of a firewall. Unauthorized disclosure of such information can reveal the fundamental principles and methods for the protection of the whole network, especially in ubiquitous environments where a large number of nodes store knowledge about the security policy of their domain. To avoid this risk we suggest a scheme for protecting stateless security policies using one-way functions. A stateless policy is one that only takes into consideration, the current event, and not the preceding chain of events, when decisions are made. The scheme has a simple and basic design but can still be used for practical implementations, as illustrated in two examples in real-life enviroments. Further research aims to extend the scheme to stateful policies.