<P> In computer security, a side - channel attack is any attack based on information gained from the implementation of a computer system, rather than weaknesses in the implemented algorithm itself (e.g. cryptanalysis and software bugs). Timing information, power consumption, electromagnetic leaks or even sound can provide an extra source of information, which can be exploited . </P> <P> Some side - channel attacks require technical knowledge of the internal operation of the system, although others such as differential power analysis are effective as black - box attacks . The rise of Web 2.0 applications and software - as - a-service has also significantly raised the possibility of side - channel attacks on the web, even when transmissions between a web browser and server are encrypted (e.g., through HTTPS or WiFi encryption), according to researchers from Microsoft Research and Indiana University . Many powerful side - channel attacks are based on statistical methods pioneered by Paul Kocher . </P>

What is side channel attack in cloud computing