Professional Video Over IP - Network Delay Variation

Network Delay Variation

Network delay variation can be kept to a minimum by using a high-speed network backbone, and ensuring that video traffic does not encounter excessive queue delays. This is typically done by either ensuring that the network is not too close to its full capacity, or that video traffic is prioritized using traffic engineering techniques (see below).

The remaining delay variation can be removed by buffering, at the expense of added time delay. If forward error correction is used, a small proportion of packets arriving after the deadline can be tolerated, since they can be dealt with by being discarded on receipt, and then treated in the same way as lost packets. Added time delay is particularly unwelcome in PTZ cameras as it makes operator control difficult at values over 250ms.