Abstract
Today, organizations in both public and private sectors have become increasingly dependent on electronic data processing. This digital data are going through an insecure channel from one place to another and anyone can easily get those important data without the concerns of the sender. So, protecting these important data is crucial task in data communication and Public Key Cryptography is one of the best ways to protect digital data from the unauthorized access. RSA algorithm is extensively used in the popular implementations of Public Key Infrastructures. In this paper, we have done an efficient implementation of RSA algorithm for speech data encryption and decryption. At first, five hundred Bangla speech words were recorded from six different speaker and stored as RIFF (. wav) file format. Then our developed program was used to extract data from these words and this data were stored in a text file as integer data. Finally, we used our implemented program to encrypt and decrypt speech data.