Date Added: Dec 2009
Synchronization over packet-switched networks has been attracting increasing attention lately, e.g. due to migration to IP transport in GSM networks. Timing is distributed by sending packet flows with constant rate. At the receiver, timing is recovered mostly based on PLL schemes that equalize packet random delay. The performance of these schemes depends significantly on the statistics of packet jitter, thus yielding a growing interest for real data measurement. The authors developed an experimental setup to measure IP packet jitter by active probing, aiming at statistical characterization of packet jitter in real heterogeneous networks.