Wireless sensor networks have been widely used in many areas, such as earthquake monitoring, building structure monitoring, and military surveillance. In this work, we focus on the wireless sensor network deployed in the battlefield, using random key predistribution scheme. Based on the node cloning attack, we proposed a new attack scheme, called compromised key redistribution attack, and discussed related attack scenarios. Furthermore, we have exposed that, when the overlapping factor of compromised key set is larger than 0.05, it is almost 90% that the number of distinct compromised keys is 10.5% of the original key pool. This result helps the adversary estimate the approximated size of original key pool by calculating the overlapping factor, thus calculate the probability that malicious nodes successfully establish malicious connections with legitimate nodes.

The transport information security provided by vehicles under VANET environment is quite important. The advantages of the method proposed in the essay are as follows: 1. Communication equipments could validate the information mutually through IBC; 2. Vehicles could validate the legality of public/private key. 3. Vehicles need not show any certificates to validate the identity, so as to avoid the certificates from attacking owing to long-term exposure; 4. The vehicle information could be validated through chameleon method, without waiting for RSU to validate the information, which could improve the instantaneity of the information; 5. The vehicles need not revalidate the identities and consult common key during the time of Hand-off within different RSU ranges.