Security Assessment of Networks

In this chapter, a novel performance model for assessing security of a layered network has been proposed. The work is motivated by the fact that there is a need for a reference framework to account for all threats to a networked system. There are few such models available, and one of them is recommended by the International Telecommunications Union (ITU). The proposed assessment model is based on the ITU security framework, recommended in the ITU-T Recommendation X.805. We employ this model to quantify network security against five threat categories mentioned in the recommendations. The quantification has been done based on the recommended measures against all threats. A threat vector has been proposed that defines required measures for a particular threat category. Other vectors, such as the security implementation vector define how effectively these measures are implemented in a given device, system, or network. As a simple application of the proposed model, the security provided by the IEEE 802.15.4 standard is analyzed, viewing it as an ‘end-to-end’ system (e.g., for ad hoc sensor network applications). The proposed security assessment model can be applied to any type of network (wireless, wired, optical, service oriented, transport, etc.). The model can be employed to obtain security assessment in the form of five security metrics, one for each threat category (destruction, corruption, removal, disclosure, and interruption). An expression for the overall security against all threats has also been derived. DOI: 10.4018/978-1-61350-101-6.ch111