Research And Design Of Efficient Cross-technology Neighbor Discovery Protocol

In recent years,the intelligent production and services provided by the Internet of Things have brought great convenience to people's lives,and the demand for communication between IoT devices using different wireless communication technologies is also increasing.The emerging research direction of cross-technology communication has proved the feasibility of these heterogeneous devices for direct communication,and its light weight characteristics will give it a broad application prospect.Neighbor discovery is a key to communication between devices.It can provide related device information for network topology and routing protocols.However,at present,the importance of cross-technology neighbor discovery has not got enough attention.In view of the fact that there is no protocol for cross-technology neighbor discovery currently,this paper takes WiFi devices and ZigBee devices for example and presents several design principles.Firstly,we focus on the discovery problem between two heterogeneous devices and propose a novel model.The incompatibility of the physical layer as well as the difference in transmission power between heterogeneous devices make it difficult to obtain neighbor information.Based on the existing work in cross-technology communication,we propose a neighbor information transmitting mechanism.In this way the device to be discovered broadcasts ID information at the beginning and end of an active slot.This protocol can meet different delay or energy requirements based on existing neighbor discovery algorithms.Furthermore,we study a more complex situation where multiple ZigBee devices and a WiFi device need to discover each other.Conflicts between signals will occur in this scenario because multiple ZigBee devices sending neighbor information to the WiFi device at the same time.We noticed that the CSMA/CA mechanism utilized by devices will lead to the hidden terminal problem,and if devices follow the originally designed protocol,a long time for successful discovery will be needed.Therefore,We have designed two discovery protocols for multiple devices in this paper,which are both based on the principle of distribution.The core idea is that the WiFi device coordinates the time when ZigBee devices send their neighbor information after slot alignment between devices.The difference between the two protocols is whether the WiFi device adaptively adjusts its listening time.Then we present the calculation results of their performance on delay and energy consumption respectively.Through the experiments we designed,the feasibility of the three protocols is verified.According to the experimental result,we summarize the difference in device energy consumption and discovery delay under different parameter settings,and the optimal parameters for the protocol to achieve efficiency are determined.Users can also regard the result as a reference standard or a guidance when selecting a protocol.