Stream Ciphers and Side-Channel Analysis ?

In this short note we review the state-of-the-art of sidechannel attacks on implementations of stream ciphers. We overview published work. We also survey the most commonly used countermeasures and how they influence the cost and security of an implementation. The recommendations given in this note result from our practical experience with side-channel attacks and countermeasures in general, and from the experience gained by a master thesis, which was devoted to side-channel analysis on stream ciphers only.