QoS-driven network coded wireless multicast

Wei Pu, Chong Luo, Feng Wu, Chang Chen
2009 IEEE Transactions on Wireless Communications  
Emerging wireless multicast applications simultaneously impose two requirements to the underlying communication networks: to provide sufficient bandwidth and to support a variety of quality-of-service (QoS) sensitivities. For the first requirement, network coding has been proposed recently as an effective way of improving bandwidth utilization. However, almost all previous works about network coding focus on the throughput gain without considering the QoS requirements. Optimal network code
more » ... ruction in wireless multicast under different QoS constraints remains as a significant challenge. In this research, we study the QoS-driven network coding problem. We use large deviation principle to establish the relationship among source rate, link condition, QoS requirement, and network code. Using this relationship, under given QoS requirements, we solve the optimal network code construction problem. The proposed network code supports maximal source rate without violating the QoS requirements. These results constitute the foundations for future designing and implementing network coding based wireless multicast protocols. Index Terms-Large deviations, multicast, network coding, queueing networks, quality of service (QoS), wireless. I. Introduction A S broadband wireless access becomes increasingly pervasive, the demand for multicast protocol to support one-to-many wireless applications such as video conferencing and multimedia streaming intensifies rapidly. Compared with traditional voice services, these new applications are not only bandwidth consuming but also QoS sensitive. Due to the time varying wireless fading channels, the heterogeneous link conditions, and the QoS requirements, it is a challenging task to design a wireless multicast protocol that scales well to client number, adapts to channel variation and link heterogeneity, and efficiently utilizes the bandwidth resources. Recently, network coding [1][2][3] is introduced to wireless multicast [4] [5] . Network coding makes full use of the broadcast nature of wireless channels. By algebraically combining the packets, network coding scheme can serve different clients simultaneously, which results in significant network throughput gain. However, almost all of the existing works about wireless network coding are studied under the framework of information theory, linear programming, abstract algebra, or combinatorics. With different emphases, these Manuscript
doi:10.1109/twc.2009.090203 fatcat:iqawzncmhfd2ngre272yohfinm