Research And Implementation Of Ad Hoc Network Protocal With Flexible Distributed Addressing

With the vigorous development of the Internet of Things,wireless embedded networked devices pervade all aspects of life,and these devices together constitute a huge wireless sensor network(WSN).When faced with the problem of networking large-scale equipment,traditional IP is facing the problem of address shortage;the 6LoWPAN protocol that emerged at the historic moment realizes the communication of IEEE 802.15.4 protocol and IPv6 protocol,and has the advantages of low power consumption,which is good for sensor networks.embedded devices.However,IPv6,which has the same fixed-length design as IPv4,cannot allocate addresses flexibly,and cannot fundamentally solve the existence of "island nodes" when faced with the needs of ultra-large-scale equipment networking in the future.Based on the framework of NewIP,this paper adopts a flexible and variable-length address structure and an extensible binary address addressing method,so that the network has complete scalability and free and unlimited address space,fundamentally breaking the "island" The possibility of existence;and proposed an address selection algorithm to optimize the network structure,and a routing repair algorithm to quickly and efficiently deal with network failure nodes and restore normal communication;finally,based on the Contiki embedded operating system,develop a network protocol stack in the kernel,A prototype system of a complete distributed elastic addressing ad hoc network protocol is realized.The research content and related work of this paper include the following four points:(1)Based on the distributed address coding and allocation method of elastic addressing,the topology information is added to the address coding;and a distributed address allocation scheme is proposed,using the subtree root The node,that is,the relay node,is used as the address distribution node,and the distribution work is placed on multiple nodes to avoid single-point distribution of addresses;and according to the network structure and addressing method,a stateless routing and forwarding protocol is designed to effectively reduce the additional resource overhead of the routing table;(2)Aiming at the reasonable flattening of the overall topology of the network,an optimal address selection algorithm with short address priority is proposed,which comprehensively considers the remaining energy of the node,the load situation and the current address length when selecting the parent node,and guarantees as much as possible The network is flattened and expanded,and the unstable nodes are actively screened to actively improve the overall life of the network;(3)Aiming at the problem of link interruption caused by network failure nodes,a routing repair algorithm based on patch routing is proposed,which is compatible with Complementing the global repair,by adding a certain amount of patch routing table overhead,it reduces the time and control overhead for faulty sub-network nodes to re-acquire addresses,ensuring long-term network stability and rapid recovery capabilities.(4)Based on the Contiki embedded operating system,the overall protocol stack prototype system is divided into two parts,the control subsystem and the forwarding subsystem,and the requirements analysis,overall design and detailed design are carried out,and finally the function points are tested and verified.The distributed elastic address allocation scheme in this paper,combined with the short address priority optimal address selection algorithm,and Zigbee’s AAN tree address allocation algorithm in the three dimensions of address allocation success rate,average address allocation delay,and average address allocation control overhead Performance experiments have been carried out.In the best case,the address allocation success rate is 1.72%higher than that of the AAN algorithm.The average address allocation delay is slightly lower than the AAN algorithm,but the average address allocation control overhead is higher than the AAN algorithm.There are redundancy issues in the address allocation message and allocation process.In addition,in terms of route repair performance,compared with the RPL-LFR algorithm,the route repair algorithm based on patch routing reduces the average end-to-end delay by about 5.3%,and reduces the control overhead by about 1.75%.