Misuse cases are a way of modeling negative requirements, that is, behaviors that should not occur in a system. In particular, they can be used to model attacks on a system as well as the security mechanisms needed to avoid them. However, like use cases, misuse cases describe requirements in a high-level and informal manner. This means that, whilst they are easy to understand, they do not lend themselves to testing or analysis. In this paper, we present an executable misuse case modeling language which allows modelers to specify misuse case scenarios in a formal yet intuitive way and to execute the misuse case model in tandem with a corresponding use case model. Misuse scenarios are given in executable form and mitigations are captured using aspect-oriented modeling. The technique is useful for brainstorming potential attacks and their mitigations. Furthermore, the use of aspects allows mitigations to be maintained separately from the core system model. The paper, supported by a UML-based modeling tool, describes an application to two case studies, providing evidence that the technique can support red-teaming of security requirements forn realistic systems.

Vehicular ad-hoc networks (VANETS) provide distributed real time communication of traffic hazards and road conditions among vehicles in a radio line of sight. We propose using VANETS to securely communicate with positive train control (PTC) systems in order to reduce highway rail intersection (HRI) incidents. This paper illustrates the similarities and differences between the two systems, discusses previous research into the work already done to integrate the two systems, and outlines the additional work necessary to successfully integrate the two systems.

The implementation of railroad PTC systems in the United States has been hindered by the lack of a suitable regulatory environment. Understanding implementation efforts have often been further hindered by lack of a clear understanding of the basic PTC architecture and functionality. This paper summarizes the recent regulatory change that supports the implementation of PTC in the United States. The final regulation poses its own challenge, especially when a government agency and a regulated industry need to make a transition from prescriptive-based to performance-based standards. However, the new regulations provide positive benefits over previous prescriptive approaches in implementing PTC. This paper describes basic PTC architectures and functionality being adopted in the railroad environment, and closes by highlighting two different implementations of the same basic PTC architecture