Analysis of information sources in references of the Wikipedia article "Blowfish (cipher)" in English language version.
At this point, though, I'm amazed it's still being used. If people ask, I recommend Twofish instead.
Blowfish should not be used to encrypt files larger than 4Gb in size, but Twofish has no such restrictions.
For a cipher with an eight-byte block size, you'll probably repeat a block after about 32 gigabytes of data. This means if you encrypt a single message larger than 32 gigabytes, it's pretty much a statistical guarantee you'll have a repeated block. That's bad. For this reason, we recommend you not use ciphers with eight-byte data blocks if you're going to be doing bulk encryption. It's very unlikely you'll have any problems if you keep your messages under 4 gigabytes in size.
Blowfish should not be used to encrypt files larger than 4Gb in size, but Twofish has no such restrictions.
For a cipher with an eight-byte block size, you'll probably repeat a block after about 32 gigabytes of data. This means if you encrypt a single message larger than 32 gigabytes, it's pretty much a statistical guarantee you'll have a repeated block. That's bad. For this reason, we recommend you not use ciphers with eight-byte data blocks if you're going to be doing bulk encryption. It's very unlikely you'll have any problems if you keep your messages under 4 gigabytes in size.
At this point, though, I'm amazed it's still being used. If people ask, I recommend Twofish instead.
