The following technical report is available from http://aib.informatik.rwth-aachen.de:

Tampering with Motes: Real-World Physical Attacks on Wireless Sensor Networks Alexander Becher, Zinaida Benenson, Maximillian Dornseif AIB 2005-24

Most security protocols for wireless sensor networks (WSN) assume that the adversary can gain full control over a sensor node through direct physical access (node capture attack). But so far the amount of effort an attacker has to undertake in a node capture attack is unknown. In our project we evaluate different physical attacks against sensor node hardware. Detailed knowledge about the effort needed for physical attacks allows to fine tune security protocols in WSNs so they provide optimal protection at minimal cost.