> It's multiplicative, not additive. 3DES is about 2^56 times as difficult to crack as DES. (Not 2^112 times because there is an attack that effectively limits

> It's multiplicative, not additive. 3DES is about 2^56 times as difficult to crack as DES. (Not 2^112 times because there is an attack that effectively limits it to twice the effective bits of DES, rather than the three times you might expect at first). If you’re using 3 different keys, yes, that makes sense. But if you’re just keystretching one key, wouldn’t it just take 3 times as long because you encrypt, decrypt, encrypt (3 processes)?