Protocols for Secure Communication in Wireless Sensor Networks

2.1. Applications of Wireless Sensor Networks 11
abled to tell if they are close to other devices, especially if they are carried by
the same person. Simple accelerometers are used to accomplish this. Also with
accelerometers, different user activities can be recognized as described in [92].
The authors attached sensors to major joints of the user’s body, including knees,
elbows and shoulders. The results collected from experiments indicate that activities
like walking or writing on a whiteboard can be recognized with high
accuracy with such rather simple sensoric equipment.
2.1.3 Other Applications
Several sensor networks have been prototypically deployed for scientific
(e.g. [199]), military and other purposes. A survey of projects can be found,
e.g., in [47] and [157]. Examples include
• environmental monitoring, e.g. in wineyards, forests, and glaciers;
• self-repairing minefields 1 ;
• improved care for the elderly through activity monitoring;
• equipment monitoring in industrial installations;
• sniper detection.
To our knowledge, security – in the sense of protecting the sensor network
against intrusion or data manipulation – has not been an active focus of practical
deployments, which is likely due to their prototypical nature and the emphasis
on technical and algorithmic problems that have to be solved for putting such
a network into operation. However, as the significance of sensor networks increases
in critical military, social, and industrial applications, security issues
will become more important. The example of the Internet shows that its potential
in business applications today is often constrained by security-relevant
threats. Thus, it is crucial to anticipate possible threats to sensor networks and
be prepared to provide suitable countermeasures in order to support a smooth
integration of sensor networks into applications.
2.1.4 Security Concerns
Although prototypical deployments of sensor networks have not been equipped
with security measures until now, it is foreseeable that adequate security is a
1 Such military applications raise important ethical questions that have hardly been addressed in the literature.
They go beyond the scope of this work, but readers are encouraged to develop awareness of these issues.