The book presents the audio signals transmission over the fixed and mobile wireless networks. Also, it focus on the mobility effects on the amount of lost packet and the quality of the received audio signals. The mobility effects on the audio signals is studied with different velocity using the Jakes model. There are many the proposed approaches are presented for combating the mobility bad effects and enhancing the traditional techniques of the sender-based packet loss error recovery. an inefficient error recovery based on weak FEC scheme can be converted to efficient sender based error recovery if merged with powerful data randomizing tool.