Multimedia Network Coding Overview
© 2012 EPFL
Review of Network Coding for Multimedia Communications, accepted for publication in IEEE Transactions on Multimedia
Network Coding Meets Multimedia: a Review
Enrico Magli, Mea Wang, Pascal Frossard, Athina Markopoulou
While every network node relays messages in a traditional communication system, the recent network coding (NC) paradigm proposes to implement simple in-network pro- cessing with packet combinations in the nodes. NC extends the concept of “encoding” of a message beyond source coding (for compression) and channel coding (for protection against errors and losses). This has been shown to increase network throughput compared to traditional networks, to reduce delay and to provide robustness to transmission errors and network dynamics. These features are so appealing for multimedia applications that they have spurred a large research effort towards the development of multimedia-specific NC techniques. This paper reviews the state-of-the-art of NC for multimedia applications and focuses on the techniques that have been specifically designed in order to fill the gap between NC theory and practical applications. It outlines the benefits of NC with a comprehensive overview of the recent research work and presents the open challenges in this area. The paper initially focuses on multimedia-specific aspects of network coding, and particularly delay, in-network error control, and media-specific error control. They permit to handle varying network conditions as well as client heterogeneity, which are critical to the design and deployment of multimedia systems. After introducing these general concepts, the paper reviews in detail two applications that lend themselves naturally to NC via the cooperation and broadcast models, respectively peer-to-peer multimedia streaming and wireless networking.