Chapter 7: Cryptography - Types of Symmetric Systems

Data Encryption Standard (DES) - Algorithm is block symmetric. 56-bit true key bit. Block size is 64-bit. Has 16 rounds of computation.

3DES (Triple DES) - When encryption occurs, applies DES three times to each block of data.

Blowfish - Block size is 64-bit and keys can vary in length. Anyone can use it.

Rijndael - Chosen for AES. Block size is 128-bit and different key lengths are used (either 128 bits, 192 bits, or 256 bits).

International Data Encryption Algorithm (IDEA) - Block size is 64-bit and uses a 128-but key.

RC4 - This is a stream cipher. Key size can change. Simple, fast, but an easy target for attackers.

RC5 - Block cipher whose block sizes can be 32-bits, 64-bits, or 128-bits.Key has a limit of 2048-bits.Round limit is 255.

RC6 - Built upon RC5 and is the same for the most part. However, it is quicker than RC5.

Advanced Encryption Standard (AES) - Standard in the United States that replaced DES. 128 block size and key lengths vary from 128, 192, and 256.

Secure ans Fast Encryption Routine (SAFER) - Similar to DES but harder to break because of the size of the key is bigger. No known successful attacks as of now. It is also patented, so you have to pay to use it.