Real time secure end to end communication over GSM network

GSM network is the most widely used communication network for mobile phones in the World. However the security of the voice communication is the main issue in the GSM network. This paper proposes the technique for secure end to end communication over GSM network. The voice signal is encrypted at real time using digital techniques and transmitted over the GSM network. At receiver end the same decoding algorithm is used to extract the original speech signal. The speech trans-coding process of the GSM, severely distort an encrypted signal that does not possess the characteristics of speech signal. Therefore, it is not possible to use standard modem techniques over the GSM speech channel. The user may choose an appropriate algorithm and hardware platform as per requirement.