Murdering Thug wrote:
Yes I do think the idea of making a "more random than random" stream by filtering out long runs of 0's or 1's weakens the the key stream in theory, but in practical use it strengthens it, because if the stream is left alone, runs of 500 bits of 0's or 1's can come through, and any fool can then extract plain text using XOR in this area of the cyphertext.
this is a one in 2^500 event. just to remind you, 2^500 is 3,273,390,607,896,141,870,013,189,696,827,599,152,216,642,046,043,064,789,483,291,368,096,133,796,404,674,554,883,270,092,325,904,157,150,886,684,127,560,071,009,217,256,545,885,393,053,328,527,589,376 (sorry to those folks whose screens get bugged by looooong lines.) i wouldn't worry about a 1 in 2^500 event occurring too often ... peter