Control scheme analysis for multimedia inter- and intra-stream synchronization

In this paper we study the inter- and intra- steam synchronization control schemes in networks with large end-to-end delays. We analyze pros and cons of different types of control schemes, focusing on the performance criterion of minimizing the jitter variance with the media stream for intra-stream synchronization, considered the most important objective. The minimum variance controller model is introduced to analyze the feasibility of feedback control schemes to achieve this objective. Due to the constraints of the distributed multimedia system model, especially when the average end-to-end network delay d_avg is large (compared to the duration of the playback of the full buffer, 2Δ), we show that within a single stream (at least the master stream), the playback performance of any kind of feedback control scheme cannot be better than the uncontrolled system. Therefore, we can remove the feedback loop to reduce communication overheads and computation complexity. Given the increasing size of global networks and the integration of wireless services the delays are gradually increasing, making this result of increased importance in the emerging networking paradigms.