Developing secure systems: issues and solutions

Specific issues associated with the development of secure systems are described. The authors focus on what an application of a mathematically-based development method means, within the constraints of a traditional development process. They then describe their experiences in the development of a secure internet system, the Multinet Gateway System. The description outlines the solutions developed in response to some of those issues. Among the results obtained is that a formal method can be defined and incorporated that yields a development process with noticeable positive effects