Quality Of Service (QoS) - Audio

Audio Quality – Audio Quality is the ability of the system to recreate the key characteristics of an original audio signal. Audio Quality can be affected by many factors such as the type of audio codecs (audio compression), transmission system and bandwidth limits.

Generally, the more the audio is compressed, the lower the audio quality.

Recently, innovations in audio compression technology have helped audio files remain small in size and still deliver the characteristics of a high quality, large size audio signal.

The symptoms of a poor transmission system include audio distortion which is caused by packet loss and/or packet corruption. Packet loss is the inability of the network to deliver a packet to its destination within a specified period of time. Packet loss can result from a variety of events such as network congestion or equipment failures. The effect of packet loss on audio distortion is to temporarily mute or distort the audio signal. Packet losses are rare as systems normally resend a data packet if it gets a reply from the destination that the original data packet failed to reach within a specified time.

Packet corruption is the modification of packet data during its transmission. Packet corruption can occur due to various reasons such as poor communication line quality or momentary line loss from electrical spikes. As IPTV systems use audio compression, the packet data represents a sound that will be recreated rather than a specific portion of the actual audio signal. As a result, if corrupted data is used, this can create a very different audio sound (Warble) then expected.