Biblio

In this paper, System Theoretic Process Analysis (STPA) method was used to analyze the security of Temporary Speed Restriction (TSR) sending scenario in train control system based on vehicle-vehicle communication. The security of this scenario was analyzed according to the analysis process of STPA method. Firstly, Unsafe Control Actions (UCAs) in this scenario were identified and Control Defects (CDs) were analyzed. After that, the corresponding Security Design Requirements (SDRs) were formulated according to the obtained control defects. Finally, the time automata network model of TSR sending scenario was established to verify SDRs. The result shows that: STPA method is suitable to discover the unsafe factors and safety hazards of train control system and take corresponding safety measures to prevent the occurrence of accidents.

Industrial Control Systems (ICS) are found in critical infrastructure such as for power generation and water treatment. When security requirements are incorporated into an ICS, one needs to test the additional code and devices added do improve the prevention and detection of cyber attacks. Conducting such tests in legacy systems is a challenge due to the high availability requirement. An approach using Timed Automata (TA) is proposed to overcome this challenge. This approach enables assessment of the effectiveness of an attack detection method based on process invariants. The approach has been demonstrated in a case study on one stage of a 6- stage operational water treatment plant. The model constructed captured the interactions among components in the selected stage. In addition, a set of attacks, attack detection mechanisms, and security specifications were also modeled using TA. These TA models were conjoined into a network and implemented in UPPAAL. The models so implemented were found effective in detecting the attacks considered. The study suggests the use of TA as an effective tool to model an ICS and study its attack detection mechanisms as a complement to doing so in a real plant-operational or under design.

In the process of big data analysis and processing, a key concern blocking users from storing and processing their data in the cloud is their misgivings about the security and performance of cloud services. There is an urgent need to develop an approach that can help each cloud service provider (CSP) to demonstrate that their infrastructure and service behavior can meet the users' expectations. However, most of the prior research work focused on validating the process compliance of cloud service without an accurate description of the basic service behaviors, and could not measure the security capability. In this paper, we propose a novel approach to verify cloud service security conformance called CloudSec, which reduces the description gap between the cloud provider and customer through modeling cloud service behaviors (CloudBeh Model) and security SLA (SecSLA Model). These models enable a systematic integration of security constraints and service behavior into cloud while using UPPAAL to check the conformance, which can not only check CloudBeh performance metrics conformance, but also verify whether the security constraints meet the SecSLA. The proposed approach is validated through case study and experiments with a cloud storage service based on OpenStack, which illustrates CloudSec approach effectiveness and can be applied in real cloud scenarios.