  Rijndael algorithm was unanimously chosen as the Advanced Encryption Standard
(AES) by the panel of researchers at National Institute of Standards and
Technology (NIST) in October 2000. Since then, Rijndael was destined to be used
massively in various software as well as hardware entities for encrypting data.
However, a few years back, Daniel Bernstein devised a cache timing attack that
was capable enough to break Rijndael seal that encapsulates the encryption key.
In this paper, we propose a new Dynamic Cache Flushing (DCF) algorithm which
shows a set of pragmatic software measures that would make Rijndael impregnable
to cache timing attack. The simulation results demonstrate that the proposed
DCF algorithm provides better security by encrypting key at a constant time.
