Statistical Randomness Tests On A New Version Of Trivium

Since the start of the eSTREAM project in 2004, Trivium has received the highest opinion due to its simplicity of structure and strong resistance against different attacks. In September 2009, the paper《On The Design of Trivium》published on the site of ePrint showed the reason for the divisibility of Trivium's parameters by 3, which reflected the importance of primitive polynomial in the design of stream cipher cryptosystem, and from this point of view, it also proposed two modified versions of Trivium.Enlightened by the above paper, after description of the algorithm of Trivium and the simulation of its keystream generating process by the use of Mathematica kit software, this paper applied 6 statistical randomness tests, which is proposed by Meltem S?nmez Turan, Ali Do?anaksoy and ?a?da? ?al?kpast on the site of ECRYPT, to the keystreams and the internal states generated by the original algorithm of Trivium and its modified version repectively. After tabulating the results, the randomness property of the keystream generated by the modified algorithm as well as the necessity of the cycling operation and the appending operation of three'1's in the key and IV initialization phase was shown by comparison. Finally, two more statistical randomness tests are proposed with their realization written in Mathematica language, and some assertions about the Trivium family were drawn, in the hope of being kept as a reference for futher study.