Research On Cross-layer Routing Protocol For 6TiSCH Network

With the widespread use of IoT technology,wireless sensor networks,as the core of IoT,are playing an increasingly important role.Wireless sensor networks support for data acquisition and transmission of IoT applications.However,traditional network standards do not meet the requirements of reliability and real-time performance in practical applications.Therefore,there is an urgent need for a wireless sensor network standard which has feature of high-quality network transmission.The IETF 6TiSCH working group proposed a new wireless sensor network standard6TiSCH by integrating the IEEE 802.15.4e TSCH standard and the 6LoWPAN protocol.6TiSCH uses TSCH?Time-Slotted Channel Hopping?technology to divide the available communication resources into communication units determined by channel offset and time slot offset,and realizes the deterministic data transmission process of each node in the network through the scheduling of the communication units,thereby enhancing the transmission reliability.At the same time,6TiSCH uses RPL as its routing protocol by default.Since the traditional routing metrics such as ETX adopted by the RPL routing protocol only consider part of the link quality attributes,there is a link quality evaluation bias,so its actual performance in the 6TiSCH network is not good.This paper proposes a cross-layer routing archtecture for 6TiSCH network and its core routing protocol TI-RPL.The cross-layer routing archtecture uses the Orchestra scheduling algorithm to complete the communication unit scheduling function and obtains the TSCH scheduling table.Then it calculates the link usage rate and link capacity through the scheduling statistics and transmits the information to the routing protocol TI-RPL.The TI-RPL routing protocol uses fuzzy logic to integrate the statistics information of the scheduling layer such as link usage and link capacity,with the link evaluation attributes such as packet retransmission and channel quality to calculate the holistic link quality metric LQM_CL,which is applied to the process of network topology establishment and maintenance,to achieve the goal of network topology optimization and performance improvement.The simulation results show that compared with the RPL routing protocol using routing metrics such as ETX,the TI-RPL routing protocol can improve the network packet delivery rate and reduce the end-to-end delay,so that the network can obtain better reliability and real-time performance.