Streaming video over the Internet: Approaches and directions

Due to the explosive growth of the Internet and increasing demand for multi media information on the web, streaming video over the Internet has receive d tremendous attention from academia and industry. Transmission of real-tim e video typically has bandwidth, delay, and loss requirements. However, the current best-effort Internet does not offer any quality of service (QoS) g uarantees to streaming video. Furthermore, for video multicast, it is diffi cult to achieve both efficiency and flexibility. Thus, Internet streaming v ideo poses many challenges. To address these challenges, extensive research has been conducted. This special issue is aimed at dissemination of the co ntributions in the field of streaming video over the Internet. To introduce this special issue with the necessary background and provide an integral v iew on this field, we cover six key areas of streaming video. Specifically, we cover video compression, application-layer QoS control, continuous medi a distribution services, streaming servers, media synchronization mechanism s, and protocols for streaming media. For each area, we address the particu lar issues and review major approaches and mechanisms. We also discuss the tradeoffs of the approaches and point out future research directions.