« Back to Glossary Index
Visit Us
Follow Me

Blowfish is a symmetric key block cipher that was invented by Bruce Schneier in 1993. A symmetric key cipher means the same key is used for both encrypting and decrypting data.

Here are some key points about Blowfish:

  1. Block Cipher: Blowfish encrypts data in 8-byte blocks. This means it divides a message up into chunks of 8 bytes and encrypts each of these separately.
  2. Key Length: The key can be any length up to 448 bits. However, a longer key does not necessarily mean stronger encryption, and a key length of 128 bits is typically sufficient for most purposes.
  3. Speed and Efficiency: Blowfish is known for its speed and efficiency. It’s especially good for situations where the key doesn’t change often, like a communications link or a file encryption.
  4. Replacement of DES: Blowfish was created as a replacement for the Data Encryption Standard (DES) and for uses where DES was starting to become less desirable.
  5. Twofish: Schneier also designed a successor to Blowfish called Twofish, which is a 128-bit block cipher that accepts a variable-length key up to 256 bits.

As of my knowledge cutoff in September 2021, Blowfish isn’t as commonly used as some other encryption algorithms, like AES (Advanced Encryption Standard), but it’s still seen in some contexts and is considered to be a secure algorithm when used correctly. For example, Blowfish is used in some secure virtual private network (VPN) tunnels.

You may also like...