Dynamic Substitution Model

In this paper, we present the Dynamic Injection Model (DIM) and its variant the Static Injection Model (SIM). DIM is a model that allows any iterative block cipher to accept a variable length secondary key, this is achieved by injecting the block cipher with keyed transformation functions. A transformation function can vary in strength from a simple xor function to a complete block cipher. The transformation functions modify the input or the output of some (all) round functions of that cipher using the secondary key. SIM is a variant of DIM, where the transformation functions and the secondary key length are determined in the design time. We used the Advanced Encryption Standard (AES) to demonstrate the usage of DIM and SIM models. Keywords—AES, DIM, SIM, multiple keys encryption.

• Type: Conference
• Year: 2008
• Where: IEEEIAS
• Authors: Mohamed Abo El-Fotouh, Klaus Diepold
• Keywords: Block Cipher, IEEEIAS 2008, Information Technology, Secondary Key, Transformation Functions