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hi, |
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|
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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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|
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3DES and IDEA are very strong ciphers |
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unless you are a terrorist, or you have discovered a secret of perpetum |
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mobile (or at least cheap way of doing |
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hydrogen fusion on a mass scale), noone is going to invest the money |
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required to break your 3DES/IDEA |
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encryption keys |
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|
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on the tech side, 3DES/IDEA are symmetric ciphers, usually accompanied |
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by asymmetric ciphers responsible for |
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exchange of encryption keys (for 3DES/IDEA) - yet another cipher to take |
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into considerations |
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there are some hardware devices able to (tremendously) speed up breaking |
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of asymmetric ciphers like RSA/DSA, |
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so this can be a shortcut to get your message decrypted |
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(and of course, don't forget known plaintext attacks - or even key |
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loggers for that matter), if your users are using |
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windows, they have much much bigger problem there and should not be |
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concerned by cryptographic strength of |
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3DES/IDEA (even ROT13 can be more secure then windows on your desktop) |
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|
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> Another question: technically, how does IDEA compare to 3DES on cipher |
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> strength and CPU usage? Is 3DES more safer than IDEA and cost more CPU |
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> time? |
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|
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both are enough secure ciphers with respect to current state of |
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cryptanalysis |
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if you want to develop your own app, you may prefer 3DES because IDEA is |
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patented (AFAIK) |
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on the other side, IDEA is faster (current implementation of IDEA are |
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approx twice as fast as DES implementations) |
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|
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at the end of the day, it is not important for users, they are |
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threatening their own security by clicking on every .exe |
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attachment they get |
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but of course, no user wants to hear that HE is the weak link in the chain |
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|
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regards, |
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martin |