Improved request-to-send (RTS)/clear-to-send (CTS)-based method for controlling congestion of multi-hop wireless network

Abstract

The invention discloses an improved request-to-send (RTS) / clear-to-send (CTS)-based method for controlling congestion of a multi-hop wireless network. The method comprises the following steps that: adjacent nodes serving as sending parties or receiving parties in the network issue congestion status information per se; when a transmitting node is in a congestion state, a request-to-send with congestion status (RTSC) request frame having the congestion state sends a request to a target node; and if a receiving node of the RTSC frame is also in the congestion state and receives the request, a clear-to-send with congestion status (CTSC) frame is sent, and the receiving node starts to receive a packet from a sending node. A cache in a node is partitioned into a receiving cache and a sending cache, and the cache service condition and the wireless channel competition degree of the node are considered comprehensively to control the congestion; and a congested receiving party and a congested sending party notify the congestion status information to avoid deadlock, so that the congestion status of the node can be acquired correctly by making a small amount of improvement on the conventionalRTS frame and the conventional CTS frame.

Description

technical field [0001] The present invention relates to a wireless network (Wireless Network), an RTS / CTS handshake mechanism in the CSMA / CA protocol (the full name of RTS is Request-To-Send, and the full name of CTS is Clear-To-Send), network congestion control (CongestionControl) and transmission control The technical field of protocol (TCP), specifically relates to an RTS / CTS-based multi-hop wireless network congestion control method. Background technique [0002] Multi-hop wireless networks have a wide range of application scenarios. In such networks, network nodes are both host nodes and forwarding nodes. Such as figure 1 In , since the TCP source node S and destination node D are not within the one-hop transmission range, the data packet must be forwarded by node A and node B to reach the final destination node. As a very important transport layer protocol in the Internet, TCP (Transmission Control Protocol) was originally designed for wired networks with stable topo...

AI Technical Summary

Problems solved by technology

However, in a multi-hop wireless network, due to the mobility of nodes, the problem of hidden terminals and exposed terminals in the link layer, and the high bit error rate of wireless channels, packet loss is caused, and not all packet loss reflected in the transport layer is due to congestion

In this kind of packet loss caused by non-congestion, the TCP congestion window is reduced, so that the sending rate of TCP in the multi-hop wireless network is at a relatively low level, which ultimately reduces the end-to-end throughput.

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