This paper presents the hardware implementation of Dragon – a fast word based stream cipher, for use in wireless sensor networks. Dragon is a highly efficient word based stream cipher which takes a 128 or 256 bit key and 128 or 256 bit Initialization vector as input and produces a 64-bit key stream for each round of operation. Dragon is resistant to various forms of attacks. This paper introduces an implementation of Dragon in FPGA/Xilinx, whose memory occupancy is only 2KB which is less than the available memory of MICA2 sensor board, which is 4KB, giving compatibility for use in sensor networks due to its low complexity and high speed. The time taken for encryption is found to be 320ns due to the parallelism introduced in the hardware model and giving a data rate of 150.92MByte per second which is also compatible with 4G networks.
