Why is packet loss important?
Unlike data traffic, voice communication is very sensitive to packet loss. In IP data traffic, devices detect packet loss and simply retransmit the lost packets automatically; this process works so well for data traffic, users are likely to be unaware of significant packet loss on their IP connection. However, such retransmission of lost packets is not an option with voice over IP: the latency resulting from detecting and retransmitting a lost packet would cause the retransmitted packet to be unusable. Any lost voice packet is lost for good; so, if packet loss occurs during speech, distortion will occur. Even a single lost packet can result in an audible pop or click. Significant packet loss will result in a crackling sound.
