A Scheme Of Congestion Control Based On Cross-layer Design In Multihop Wireless Network

The development of Internet makes it easier to get information, and helps develop people a habit depending on the Internet. If the Internet is impossible to use, there will have a strong impact on people`s life and work. Congestion of the Internet is one of the possibilities of make it paralysis, so network congestion is studied widely. For the reason that the link rate in the multihop wireless network is determined by the translating power of the link, a congestion control scheme based on cross-layer design is proposed in this paper, combining the power control problem and congestion control problem. Queue length is designed to monitor the congestion of the network in order to discover the congestion before it happens.Firstly, the congestion control problem is discussed in multihop wireless network considering power assignment with the condition that the global network information is known. The congestion of the network is monitored by the queue length of each link. When the value of queue length is larger than the threshold, the link will send an early warning to the network. The flow who uses the congested link will reduce its data rate to avoid the congestion.Then a local congestion control mechanism is proposed in multihop wireless network. The queue length of the link is used to monitor the congestion, when its value is larger than the threshold, the congested link sends an early warning to its upstream links and an adjustment of rate. When a link gets an early warning and an adjustment from downstream links, it adjusts its translating rate. This adjustment is completed when there is no link send warning information.