Wireless Sensor Networks pt 1: Introduction - Sensor Research Challenges

Due to sensors’ limited capabilities, there are a lot of design issues that must be addressed to achieve an effective and efficient operation of wireless sensor networks.

• Energy saving algorithms. Since sensor nodes use batteries for power that are difficult to replace when consumed (remember that often sensor nodes are deployed in remote and hostile environments), it is critical to design algorithms and protocols in such a way to utilize minimal energy. To do so, implementers must reduce communication between sensor nodes, simplify computations and apply lightweight security solutions.
  
• Location discovery. Many applications can tracking an object require knowing the exact or approximate physical location of a sensor node in order to link sensed data with the object under investigation. Furthermore, many geographical routing protocols need the location of sensor nodes to forward data among the network. Location discovery protocols must be designed in such a way that minimum information is needed to be exchanged among nodes to discover their location. Since sensor nodes are energy constrained, solutions like GPS are not recommended. After all, cost is another factor that influences design; manufacturers try to keep the cost at minimum levels since most sensor nodes are usually needed for many applications. If the cost is high, the adoption and spread of sensor technology will be prohibited.
  
• Security. Is it possible to introduce a new technology without addressing security? Of course not! However, as all other technologies, security is not the top priority when designing something new. This approach is acknowledged by almost everyone, and it is erroneous but they keep doing it anyway. Security solutions are constrained when applying them to sensor networks. For example, cryptography requires complex processing to provide encryption to the transmitted data. Secure routing, secure discovery and verification of location, key establishment and trust setup, attacks against sensor nodes, secure group management and secure data aggregation are some of the many issues that need to be addressed in a security context. Future articles will analyze some of these issues to give you a good understanding of security related issues in wireless sensor networks.     

Conclusion

This article was to familiarize you with fundamental issues of sensor networks so that I can later discuss security issues. In the next article, I plan to analyze in limitations of sensor networks and their security requirements. Sensor area is growing very fast, attracting more and more people to its use. Of course, to my knowledge, research on sensor security is very recent and a lot of work needs to be done in many areas that are not addressed so far. The effort made so far is recognizable by the community since this is a new area with a lot of open issues.