Research And Simulation Of High-Frequency Token Ring Protocol

It is widely that the high frequency mobile ad hoc network utilized in communication system thanks to its good performance in resisting-destroy and self-organization.The High-Frequency Token Ring Protocol(HFTRP)is a media access control protocol which is used in High-Frequency(HF)communication.As the fact that the HFTRP is originated from Wireless Token Ring Protocol(WTRP),it inherits WTRP's advantages which can ensure fair access and be robust to the single node failure,it can rapidly adapt topology variation and effectively provide good communication quality.First,this paper investigates HFTRP and adopt a novel modified algorithm for ring formation which can improve network performance.HFTRP apply a token relay method with optimistic joining to invite node.Unfortunately,unnecessary relays would be caused in the ring formation,so an optimized algorithm has been utilized in the ring formation.The steps of the optimized algorithm are introduced as follows: first,a judgement mechanism determines whether to adjust the Transmit-Order-List(TOL)or not after floating node joined the ring.Second,if necessary,the nearest insertion algorithm would insert the node which need to be relayed to a suitable place of TOL.Then,the key technologies of HFTRP has been analyzed and researched,including leaving ring,token relay and merging rings.Subsequently,the HFTRP is simulated on OPNET,and the performance of HFTRP is analyzed in various conditions.The experimental results indicated that the ring formation with modified algorithm can provide better throughput,decrease time delay and effectively avoid the unnecessary relays.The C++ coding and modularization implemented with VS2008,and the accuracy and stability of HFTRP has been verified.The experimental results demonstrated that the state mechanism of HFTRP is a whole unit,its accuracy can ensure ring to form and can maintain the stability of the network.