MPEG transmission schemes for a timed token medium access control network

Abstract

This paper presents three transmission schemes to improve the transmission of MPEG video over a timed token medium access control (MAC) network. Multiple classes of MPEG video IntroductionBecause of the demands of the videos on network bandwidth, video data needs to be compressed before being transmitted over a computer network. Many compression schemes have been proposed or developed for these variable bit rate (VBR) video services. Of all these video compression schemes, the scheme developed by the Moving Pictures Experts Group (MPEG) is the most notable. By MPEG standard, video information is compressed frame by frame, and the resultant frames should be transmitted and processed under stringent timing constraints. To support such applications on top of a computer network, the underlying transmission scheme must ensure that most, if not all, frames should reach their destinations before their deadlines. Frames arriving late and missing their deadlines will result in a poorer quality of the picture or jumpy video. Hence, it is a tradeoff between video quality and on-time delivery of video frames.In order to address the issue of on-time video frame delivery, transmission delays for the underlying network must be deterministic and bounded. Here, we adopted the time token medium access control protocol because of its important property of bounded transmission delay. This bounded delay property is a necessity for real-time communications, multimedia computing systems, and industrial process controls. This is why the timed token MAC protocol has been well received and being adopted in several high-bandwidth network standards over the years.

BuST: Budget Sharing Token protocol for hard real-time communication

“…For instance, in [13] the authors show the usage of the protocol to guarantee a minimum QoS for the transmission of MPEG video. Bussiere et al [3], describe a submarine application using a distributed architecture, where hard real-time requirements are defined both for the computational activities and the data communication.…”