SAFER (Secure And Fast Encryption Routine) is a family of symmetric-key block cipher algorithms designed for encryption and decryption. SAFER was developed by James Massey and Xuejia Lai in the early 1990s as a response to the need for efficient and secure encryption algorithms. SAFER was specifically designed to provide a balance between security and speed, making it suitable for various applications.
There are different variants of the SAFER algorithm, each denoted by a number indicating the key length (e.g., SAFER K-64, SAFER K-128). The numbers in the SAFER names represent the size of the encryption key in bits.
Key features of SAFER include:
Block Cipher: SAFER operates on fixed-size blocks of data (usually 64 or 128 bits) and processes them through multiple rounds of encryption and transformation.
Substitution-Permutation Network (SPN): SAFER uses a substitution-permutation network structure, which is a common design approach in symmetric-key block ciphers.
Efficiency: SAFER was designed with an emphasis on speed and efficiency, making it suitable for applications that require encryption and decryption to be performed quickly.
Cryptanalysis and Security: While SAFER was designed to provide reasonable security, it may not offer the same level of security as some other modern encryption algorithms. As technology and cryptanalysis techniques have advanced, the security of older algorithms like SAFER may become less robust.
It's important to note that due to advances in cryptographic research and the discovery of more secure and efficient encryption algorithms, SAFER is not widely used today. Modern encryption standards, such as the Advanced Encryption Standard (AES), offer higher security and performance and have largely replaced older algorithms like SAFER in many applications.