N.S.Murtisarma, senior member of IEEE & Professor, ECE Dept, Sreenidhi Institute of Science and Technology, Telangana, India. Gobinda Prasad Acharya and P. Lavanya, Co-authors of this book are active research scholars of JNTU towards procuring their Doctoral Degree, besides their valuable services at the capacity of associate Professors at SNIST.

The work embodied in this is based on Data security. This is one of the major concerns for digital data as well as voice transmission through non-privatized networks. Hence, a significant amount of research work is needed to provide reliable and secured data/voice transmission. The CS-ACELP algorithm based G.729 codec is standardized as voice codec by ITU-T for multimedia and Voice over Internet Protocol (VoIP) applications. The encoding scheme for CS-ACELP speech codec described in this work provides on-fly security for the encoded data for a secured speech transmission. This method is based on the periodically changing the track sequence of fixed code-book index for every 100 ms speech samples sampled at a rate of 8000 samples per second and also, adapting a new technique to encode the fixed code-book index. This book presents efficient way of providing data security for G.729 codec.