Joint Congestion Control and Scheduling in Wireless Networks with Network Coding

Abstract

This paper studies how to perform joint congestion control and scheduling with network coding in wireless networks. Under network coding, a node may need to buffer a sent packet for decoding a packet to be received later. If sent packets are not forgotten smartly, much buffer space will be taken up, leading to dropping of new incoming packets. This unexpected packet dropping harms the final throughput obtained, although optimal scheduling has been used. To solve the problem, we introduce a new node model incorporating a transmission-mode preassignment procedure and a scheduling procedure. The introduced transmission-mode preassignment avoids memorizing several sent packets to reduce buffer overhead. We develop a new scheduling policy based on our node model and analyze formally the stability property of a network system using the proposed policy. We finally evaluate the efficiency of our algorithm through simulations from the perspectives of throughput and packet loss ratio.