Glossary:Side channel attack
A side channel or covert channel attack is one which exploits some side-effect of the processing, transmission or storage of data in order to draw inferences about the data itself. For example, unless carefully designed, variations in the power consumed by a processor while encrypting data can leak information about the data, perhaps ultimately leading to discovery of the encryption key. However, the rate of data leakage is usually very low, and insignificant in all but the most secure environments.