statistically for a linear correlation and/or an algebraic boolean relation (see also Differential cryptanalysis). If choosing particular values of the initialization vector does expose a non-random pattern in the generated sequence, then this attack computes some bits and thus shortens the effective key length. A symptom of the attack would be frequent re-synchronisation. Modern stream ciphers include steps to adequately mix the secret key with an initialization vector, usually by performing many initial rounds. References External links Security of the WEP algorithm "Attacks in Stream Ciphers: A Survey" – a brief 2014 overview of different stream cipher attacks "Attacks on Stream Ciphers: A Perspective" – talk slides from 2011 Cryptographic attacks