Switch Technology Based On MAC Layer Of Ad Hoc Network

Ad Hoc network is a multi-hop temporary autonomous system composed by a group of mobile terminal nodes with a wireless transceiver. Each mobile terminals acts as a communication terminal and as a router, and can move freely. So they can constitute arbitrary network topology through wireless connection. Data packet is transmitted by way of Multi-hop, while the network works without fixed infrastructure.Compared with traditional wired networks and cellular networks, Ad Hoc Networks don't have infrastructure and each node may enter and leave the network at any time, the entire network works distributely. Due to the dynamic change of topology, no central node control, limited bandwidth, limited energy and other reasons, there are many problems in Ad Hoc networks. This paper systematically studys routing protocols, clustering algorithms and other key technologies in Ad Hoc networks, and achieves some innovative research results. This paper's work includes:1. Clustering algorithm is a key technology and research central in Ad Hoc network. In large-scale MANET (Mobile Ah Hoc Network), clustering algorithms can improve the system performance of network. In this paper, we propose a new multi-hop based algorithm. The proposed algorithm can generate a relatively small number of clusters, while the size of cluster is relatively large, so as to support large-scale Ad Hoc Networks. The proposed algorithm can use the routing information to adjust the cluster topology, so as to reduce the control overhead of cluster and extend the survival time of cluster head. The purpose of clustering algorithm is to obtain scalability and efficient routing. Simulation results show that the proposed algorithm has good performance in the number of clusters and the connection rate.2. Ad Hoc network routing algorithm is an important part of Ad Hoc network, is the primary problem of data communication. Compared with the traditional networks, the design of routing algorithm in Ad Hoc network is more challenging, therefore, it becomes the research hotspot. This paper presents a new MAC layer based label switching routing protocol. The proposed protocol utilizes the header of MAC frame to carry a complete route segment, so that the process of intermediate forwarding of data transmission is mainly in the MAC layer, without requiring the involvement of the network layer. In this way, the process of forwarding reduces the route table searching time in the network layer and the processing time of package decapsulation and encapsulation, consequently reduces the transmission delay. Also, it reduces the resource requirements of network interface card and host during the intermediate forwarding of data transmission. Simulation results show that compared with AODV and DSR protocol, the proposed routing protocol has great improvement in the performance.3.This paper presents a implementation of the proposed routing protocol. The implementation uses Linux as software platform and uses ARM development board with Samsung S3C2440 chip and USB wireless network interface card as hardware platform. The implementation achieves the basic functions of the proposed routing protocol. The proposed routing protocol in this paper belongs to the on-demand routing protocol while the kernel of Linux operating system does not support the on-demand routing protocol. So the routing protocol in this paper is implemented in the driver layer of Linux operating system.