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Hi, |
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|
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Zhang Weiwu wrote: |
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> Hello. I googled around with no luck. I wish there could be some very |
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> easy explanation of cipher strengths so that I could answer questions |
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> like 'how strong 3DES is' to novice users. Most results I could find are |
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> too technical / mathematical. I want very simple explanation like this: |
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> |
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> 128 bit IDEA is very strong cipher. Normally, take a piece of encrypted |
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> data, it would need one Pentium Xeon 2GHz personal computer xxxx years |
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> to decrypt the data, this is as long as the age of the earth (or human, |
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> or USA, whatever). Even if you could use the most powerful computer now |
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> one the earth abcde (replace abcde with the computation power), you need |
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> xxx (a number) of them to decrypt it in 5 years. |
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Take a look at distributed.net site. |
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They host competitions in key-breaking using a distributed client. |
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Among one of them is the des3 standard. That might give you the |
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indication you're looking for ? |
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And maybe some more pointers on where to look for this kind of info. |
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|
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<Quote from their website> |
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On December 12, 1998 RSA officially announced that they would sponsor |
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the DES-III contest, which would start January 18, 1999 at 9am PST. To |
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meet this challenge, distributed.net again planned on using the idle |
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processing time of computers all over the world to test the at most 256 |
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keys to determine the correct one. |
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Additionally, RSA placed strict time limits on the challenge. |
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up to 24 hours to win $10,000 |
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up to 48 hours to win $5,000 |
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up to 56 hours to win $1,000 |
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more than 56 hours - nothing |
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|
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Accomplishing this great computational task required thousands of |
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people around the Internet to help out by running a special client |
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program on their computers, allowing it to connect to one of our |
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coordinating servers. When the client program ran, computers were |
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assigned a block of work to test and determine if a solution was found. |
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With this system, the more computers we had working together, the faster |
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the combined effort would be. Any machine with a reliable connection to |
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the Internet was usable for our purposes. |
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To make things even more interesting, distributed.net worked to allow |
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the EFF hardware Deep Crack to participate cooperatively within the |
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distributed.net effort. This enabled it to join its computational power |
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with the thousands of deployed distributed.net clients that were |
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participating via the Internet. Despite the immense power of the EFF |
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Deep Crack, distributed.net's thousands of deployed clients still |
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surpassed the EFF hardware by more than a factor of 2 in speed. |
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As it turned out, distributed.net was entirely successful in this |
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endeavor, and DES-III ended with success on January 19, 1999 at 7am PST, |
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yielding a solution in less than 24 hours! |
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</Quote> |
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Grtz, |
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|
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Ramon |
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