Introduction to Secure and Fast Encryption Routine Seminar Topic:

This paper discussed about an algorithm, SAFER – Secure and Fast Encryption Routine. In this algorithm, the plain text encrypts by going through S-boxes and decrypts by its inverses but not like in DES where each block is divided into parts which in turn some parts affect others.  For the entire process of encryption SAFER process undergoes eight rounds. Applying the first sub-key to the eight byte of the block is the first step for each round. The process of applying each byte of the sub-key to each byte of the block always relies on which byte is used. SAFER used for invert the encrypted plaintext by reverse each step and in this process there is a possibility of altering the sub-keys which used for encryption. 


The process of encryption and decryption of plaintext using sub-keys is same in both SAFER-128 and SAFER SK-128 algorithms.  SAFER SK is a new version of SAFER, which has a huge secure key schedule and also there exists a 40-bit version of SAFER SK. The first 64-bit sub-key was the key itself in the original version of SAFER.

The S-boxes:

The regular box indicates 45 raised to successive powers modulo 257. In S-boxes, every s-box is inverse of the preceding s-box and there may be a probability of getting intractability of the discrete logarithm problem.   Among eight rounds of SAFER process, after the eighth round an extra sub-key is added in the way that the first sub-key of each round.

Sub-key generation:

In order to generate successive sub-keys there is a need to place individual bytes of the key in a circular left shift of 3 bits between the rounds, and the yielded result is XORed with a constant which is fixed for each round.  Usually the rounds proposed for SAFER process are six but later it increased to eight. The fixed constants are obtained mathematically for up to 10 rounds. 

Download Secure and Fast Encryption Routine CS Final Year Seminar Topic with Report.