Impact of network equipment on packet delay variation in the context of packet-based timing transmission

The evolution of packet networks introduces a service requirement that neither packet equipment nor packet network were originally engineered to deliver, that is, accurate timing distribution. This article concentrates on the factors which affect the latency of packet delivery and specifically on the variable part of this latency. Change in the latency of packet delivery is called packet delay variation. PDV impacts the quality of timing distribution in the absence of specific assistance. We show the behavior of different packet equipment. We describe the possible root cause of the demonstrated behavior and put in perspective their effect on timing flows. We show that some equipment would require assistance in distributing timing packet, while others have limited bounded impact on PDV without any special assistance.