# Vulnerability Assessment of Sensor Systems
## 2 Background and Related Work
### Current State of the Research Field
#### 2.3.1 Common Criteria Application in Sensors and Sensor Systems Development  
The paper [7] contains a survey of the Common Criteria applications in the sensor systems domain. The most relevant of them concern:  
* general sensor network security aspects;* healthcare systems;
* aircraft health monitoring systems;
* safety-critical assets distribution systems;
* transport systems, including motion sensors of digital tachyographs;
* products related to SCADA (supervisory control and data acquisition);
* specialized firewalls used in control and automation systems, co-operating with sensors networks.  
A previous paper [8] considered the analysis of wireless sensor network (WSN) security based on the regulations intended for wireless communication devices. It discusses WSN attacks, security measures countering these attacks, and provides a security evaluation and classification methodology for WSN protocols (a communication stack). The Common Criteria methodology is proposed as the validation methodology of security countermeasures in WSN systems. The countermeasures' sufficiency (SFRs-based) and correctness (SARs-based) are evaluated. The countermeasures, identified as security objectives, are expressed with the use of the selected SFRs related to:  
* nonrepudiation of the origin (FCO_NRO) and source (FCO_NRR)--source and destination identifier in each message,
* user identification (FIA_UID)--introducing \"membership control-bus guardian\",
* different mechanisms related to the \"FDP user data protection\" class.  
The threat/attacks and countermeasures reference lists [8] can be used as information sources about WSN attacks and vulnerabilities in the SVAM method and to work out knowledge repositories for evaluators.  
A chapter in [9] is focused on the security and privacy issues in healthcare systems, including sensor and wireless sensor networks. Security and privacy threats are mapped to the commonly used countermeasures. The countermeasures are discussed with respect to the limits of the sensor networks, as it is difficult to apply advanced cryptographic techniques to them. The chapter remarks that assurance relies on engineering practices, development processes, operational issues, and can be evaluated according to the Common Criteria methodology.  
Below are different examples of Common Criteria applications (security analysis of a system, identifying threats, deriving security objectives, requirements, and security functions) in the sensor systems domain concerning e-Enabled aircrafts [10; 11]:  
* Electronic distribution of software (EDS),
* Airplane assets distribution system (AADS),
* Air health monitoring and management system (AHMMS),
* Air traffic control (ATC).  
The automotive industry uses similar communication channels to load assets, i.e., software or contents, to different embedded electronic control units built into vehicles [12].  
The digital tachograph system [13; 14; 15] consists of a vehicle unit, motion sensor, and a smart card used to log in to the unit. The Common Criteria standard is used to evaluate the security of tachograph systems.  
The review of these few examples concludes that the Common Criteria methodology is rarely directly used in the sensor and sensor system certification processes. Among many certified IT products (more than 2000) and registered protection profiles (more than 300), only a few are directly related to sensors and sensor systems, i.e., motion sensors for digital tachyographs and industrial control systems that include sensors.  
Apart from these certified IT products, the Common Criteria methodology is used:  
* for noncommercial, e.g., military purposes, but they are not well documented,
* as a supporting methodology to solve design problems (without certification) [8; 9].