Research Of Rate-Based Layered Multicast Congestion Control

The multicast technology is an effective method that simultaneouslytransmits the data from single sender to many receivers, and this merit causes itto become the research hot spot in the current network technology. But with themulticast application development, its congestion control problem also changesmore and more important. Now it has been one of main problems that restrictmulticast technological development. The multicast congestion control canadjust transmission rate and so on, then avoid the congestion and eliminate thecongestion. TFMCC is one of outstanding single-rate multicast congestioncontrol, and it has many merits. But it has not been able to get out of thesingle-rate multicast congestion control limit, and it has fell short of thebandwidth use ratio and expansibility. The two aspects are precisely theadvantage of the multi-rate multicast congestion control. In view of theseproblems, the paper proposes one idea, which combines the single-ratemulticast congestion control advantage and the multi-rate layered multicastcongestion control advantage, then study We improve the TFMCC by themulticast layered multicast.Firstly, we analyze the single-rate multicast congestion control limitations,and found the reasons of the problems. We propose a TFMCC-based layeredmulticast congestion control protocol, named LTFMCC. By joining the layeredmulticast mechanism, we implement the multi-rate multicast congestion controlimprovement work.Secondly, We concretely design the LTFMCC protocol. In concretelydesigning process, besides solving the TFMCC problem, we must deal withnew issues that appear because of the layered mechanism introduction. Thegoal of the CLR management and the feedback mechanism improvement is thatLTFMCC can combine the advantages of TFMCC and the layered multicast.Finally, the proof of the improvement protocol is implemented by thesimulation experiments. The simulation environment is the NS-2 networksimulator. By analyzing the simulation experiment results, we prove theenhancement of fairness, the bandwidth use ratio, and so on. So theimprovement is successful.