Abstract
The paper concentrates on one particular technological aspect of providing communications security, firewall technology. Currently firewall technology is a specialized engineering solution rather than a scientifically based solution. The paper introduces a reference model that captures existing firewall technology and allows for an extension to networking technologies to which it was not applied previously. It can serve as a framework in which firewall systems can be designed and validated. The essential components of the reference model are authentication, integrity assurance, access control, audit, and their enforcement. All components are governed by a centralized security policy, and they can be deployed in a distributed fashion to achieve scaling.