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128-bit version of double length 3DES

Is there a 128-bit version of double length 3DES available? I'm requested to implement an encryption where I receive a 128-bit key, but I cannot find any information on this length. Is the documentation wrong? Or am I?


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DES uses 56-bit keys. 3DES allows you to use one (56), two (112) or three (168) keys. I suppose an implementation of DES would allow for padding to get to 128, but I suspect someone misread (as IDEA, RC4/128 and AES all use 128-bit keys).


For more information on this topic, visit these other SearchSecurity resources:
Ask the Expert: Encryption above 3-DES
Ask the Expert: The differences between AES and DES
Best Web Links: Encryption


This was first published in June 2002

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