The Stream Cipher Polar Bear
نویسندگان
چکیده
We propose a new stream cipher called “Polar Bear”. It combines constructions used successfully in other situations. The key initialization uses Rijndael, the steady state uses a dynamic table as in RC4 and we guarantee a long period through the use of a linear feedback shiftregister. The efficiency for short messages is better than that of RC4 while for long messages Polar Bear is about a factor two behind in efficiency. On the other hand, we believe our construction has a larger safety margin compared to RC4.
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تاریخ انتشار 2005