Editing Talk:1193: Externalities

:: There should be some cleverness involved in addition to access to computers. It all comes down to who can generate the most hashes in the time available, because as a good cryptographic hash Skein gives you no hint about how to change your input to get a result closer to your target, you just have to keep making guesses. But that is not just a matter of how many computers you have. For example, Googling around for implementations of Skein I didn't find any ready to run libraries for GPUs of Skein 1024 1024. A team at a university could have stuck with an existing C implementation running on an available set of computers, or taken the time to get it running on GPUs and get quite a bit of extra speed. Also, I haven't experimented with it, but a hash function should be faster if you give it a smaller input. The current best result from CMU would take on the average about 1 quadtrillion (1e15) trials to find. Given that the input to the hash has to be in the form of URL-safe printable characters, if you assume that your team will not have time to generate more than, say 1e16 hashes and the character set you have to work with is 100 characters (my guess from looking at my keyboard) then your test input strings do not have to be longer than 8 characters. Anyone who is generating test input for the hash that is any longer, for example if they are, as a really bad example, converting 1024-bit numbers to 256 ASCII character hex, is doing at least 32 times too much work for each hash calculation. [[User:Bugstomper|Bugstomper]] ([[User talk:Bugstomper|talk]]) 00:37, 3 April 2013 (UTC)

:: There should be some cleverness involved in addition to access to computers. It all comes down to who can generate the most hashes in the time available, because as a good cryptographic hash Skein gives you no hint about how to change your input to get a result closer to your target, you just have to keep making guesses. But that is not just a matter of how many computers you have. For example, Googling around for implementations of Skein I didn't find any ready to run libraries for GPUs of Skein 1024 1024. A team at a university could have stuck with an existing C implementation running on an available set of computers, or taken the time to get it running on GPUs and get quite a bit of extra speed. Also, I haven't experimented with it, but a hash function should be faster if you give it a smaller input. The current best result from CMU would take on the average about 1 quadtrillion (1e15) trials to find. Given that the input to the hash has to be in the form of URL-safe printable characters, if you assume that your team will not have time to generate more than, say 1e16 hashes and the character set you have to work with is 100 characters (my guess from looking at my keyboard) then your test input strings do not have to be longer than 8 characters. Anyone who is generating test input for the hash that is any longer, for example if they are, as a really bad example, converting 1024-bit numbers to 256 ASCII character hex, is doing at least 32 times too much work for each hash calculation. [[User:Bugstomper|Bugstomper]] ([[User talk:Bugstomper|talk]]) 00:37, 3 April 2013 (UTC)

Is it over now that it's after midnight?  When I moused over the school name, it didn't give me a pop-up showing the next hint.  [[Special:Contributions/76.106.251.87|76.106.251.87]] 06:06, 2 April 2013 (UTC)

Is it over now that it's after midnight?  When I moused over the school name, it didn't give me a pop-up showing the next hint.  [[Special:Contributions/76.106.251.87|76.106.251.87]] 06:06, 2 April 2013 (UTC)