VHDL Implementation of Security Architecture For Bluetooth Technology Mrs.D.Sharmila, Dr.R.Neelaveni, Research Scholar, Bannari Amman Institute of Technology, Sathyamangalam.Tamil Nadu-63840 sharmiramesh@rediffmail.com Asst.Prof.PSG College of Technology, Coimbatore.Tamil Nadu -638401. rn64asok@yahoo.co.in ABSTRACT In this paper, a VHDL implementation for the SAFER+ encryption algorithm is presented. The combination of security, and high speed implementation, makes SAFER+ a very good choice for wireless systems. The SAFER+ algorithm is a basic component in the authentication Bluetooth mechanism. The relation between the algorithm properties and the VLSI architecture are described. The whole design was captured entirely in VHDL language using a bottom-up design and verification methodology. FPGA device was used for the hardware implementation of the algorithm. The proposed VLSI implementation of the SAFER+ algorithm reduces the covered area about 25 percent, and achieves a data throughput up to 320 Mbit/sec at a clock frequency of 20 MHz. Keywords: SAFER +, Encryption, PHT 1. Introduction Bluetooth is a new technology for wireless communication. The target of the design is to connect different devices together wirelessly. Wireless communication technology has advanced at a very fast pace during the last years, creating new applications and opportunities. In addition, the number of computing and telecommunications devices is increasing. Special attention has to be given in order to connect efficiently these devices. In the past, cable and infrared light connectivity methods were used. The cable solution is complicated since it requires special connectors, cables and space. This produces a lot of malfunctions and connectivity problems. The infrared solution requires line of sight. In order to solve these problems a new technology, named Bluetooth, has been developed. With this communication system, users are able to connect a wide range of computing and telecommunications devices easily and simply, without the need for connecting cables. Bluetooth technology as a cable replacement technique exposes the need for security functionalism in the wireless solution. By replacing the cable and introducing radio signals there is a need for the Bluetooth device to have built-in security to prevent eavesdropping and falsifying the message originator. Therefore, functionalism for authentication and encryption has been added to this technology. Authentication is used to prevent unwanted access to data and to prevent falsifying the message originator. Encryption is used to prevent eavesdropping. In this paper a hardware implementation of the SAFER+ encryption algorithm, for use in Bluetooth telecommunication system is presented. The proposed implementation reduced the covered area constraints about 25 percent comparing with the others implementations. In addition, achieves throughput 320 Mbit/sec, comparing with the 59 Mbit/sec of the implementation in [2] finally, the proposed implementation, achieves better performance than the software implementations, in terms of encryption throughput by a factor ranging from 9 to 12500. The paper is organized as follows: In sections 2 and 3 a brief description of the Bluetooth security features and the SAFER+ algorithm are presented. Simulation results for the FPGA implementation is shown in section 4, and the paper conclusions are given in section 5. 2. Security Architecture of Bluetooth Technology The authentication scheme is performed by using a stream-cipher (Ar), a common key and a Bluetooth address. The cipher seed generator is a version of the public SAFER+ cipher, which takes a 128 bits key and 128 bits data block and precedes the encrypted data [2]. The Bluetooth specifications include security features at the link level [1]. They support authentication (unidirectional or mutual) and encryption (Fig. 1). Fig.1 Authentication Scheme