The use of network delay estimation for multimedia data retrieval

Multimedia data have specific temporal presentation requirements. For example in video conferencing applications the voice and images of the participants must be delivered and presented synchronously. These requirements can be achieved by scheduling or managing system resources. We present a technique called limited a priori scheduling (LAP) to manage the delivery channel from source to destination for digital multimedia data. By using delay estimation a LAP scheduler can retrieve stored digital media spanning arbitrary networks with unspecified delays. The use of delay estimation also facilitates selective degradation of service in bandwidth and buffer limited situations. Such degradation enables the continuous real-time playout and synchronization of various media arriving from different sources. The performance of the LAP scheduler is described based on implementation and experimentation using Ethernet.