Does DES-EDE3 mean the same as Triple DES?

Question

I should use encryption DES-EDE3-CBC. Does this mean it is Triple DES in cipher-block-chaining mode?

Answer 1

Yes. The EDE part tells you to use the specific variant of 3DES (everyone uses by default anyway) where you encrypt with key 1, decrypt with key 2, and then encrypt again with key 3 (which is usually the same as key 1).

The (minor) advantage of that mode is interoperability with DES: Set all three keys the same and you just spend a lot of time doing single DES. Not that anyone would, these days. Even 3DES is only interesting for compatibility with existing systems. Newer ciphers are faster and more secure, as far as anyone publicly admits to knowing.

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