Hardware implementation of the improved WEP and RC4 encryption algorithms for wireless terminals

This paper presents hardware implementations for Improved Wired Equivalent Privacy (IWEP) and RC4 ("Ron\´s Cipher #4") encryption algorithms. IWEP is a block algorithm providing light-strength encryption. The algorithm has been designed for a new Wireless Local Area Network (WLAN), called TUTWLAN (Tampere University of Technology Wireless Local Area Network). On the contrary RC4, developed by RSA Data Security, Inc., is a powerful stream algorithm used in many commercial products. It is also utilized in the Wired Equivalent Privacy (WEP) standard algorithm for WLANs. The objective of this work has been to study the suitability of hardware implementation for these previously software-implemented ciphers. Hardware is needed to replace software especially in wireless multimedia terminals, in which real-time data processing and limited on-chip memory sizes are key elements. The implementations are made in Very highspeed integrated circuit Hardware Description Language (VHDL) on Xilinx Field Programmable Gate Array (FPGA) chips.