Multicast Network Congestion Control Algorithm

With the development of the information society, computer network is becoming more sophisticated. The network takes on more and more nodes. Routing strategies must be able to cope with the increasing number of packets. The ever-growing demands challenge the network topology, the network capacity. When one or more network failure of the transmission or when the number of packets exceed the network capacity, the potential consequence is that it brings on network congestion, or a large packets accumulation in one or more network nodes. Congestion in the network has serious consequences that it lowers the performance of the network, even results in breakdown of the network. So Multicast Congestion Control will become an important research topic.The paper solves two problems of multicast congestion control: quickly response to network congestion and feedback suppressed.Firstly, aiming at quickly response to network congestion, the paper analyses some existing active queue management algorithm and studies a new algorithm. When average length of queue exceeds a reference value, the algorithm adjusts the rate of packet loss percentage according to the packet arriving rate. Its queue length keeps around the reference value, so it has more stability and self-adaptability to network congestion.Secondly, taking feedback implosion into account, the paper uses the active network technique for improving router's functions and gives a kind of congestion control that is concerned with the router, which implements feedback aggregation and local recover of lost packet. Having been simulated and analyzed, the algorithm has been testified to have better scalability and utilization of bandwidth.Finally, NS, a network simulation tool, is used to analyses and validates the performance of forenamed algorithms.