Modeling And Analysis On WSN/PON Cluster-based Hybrid Network

With the increasingly development of Internet technology and communicationtechnology, Wireless sensor network (WSN) has been solved the key problem thatcollecting and transmitting large-scale data. However, the existing Access Networktechnology still has much negative impact on the interconnection between WSN andbackbone network such as Internet. Passive optical network (PON) is developed todeal with the “last mile” bottleneck problem in telecommunication network. Thetelecoms sectors greatly pay attention to it due to the ability of anti-interference,high bandwidth, high-speed and so on. In typical WSN, the sensor nodes deployed inmonitoring area always accept the command of end user to collect the informationof interest to the end user, then through one hop or multi-hop to the sink node, afterinformation aggregation the data are sent into Internet/backbone network, arrive atthe end user. The convergence of WSN and PON means the sink nodes in WSN link tooptical network units (ONUs) in PON, the bandwidth of each ONU is allocated byoptical line terminal (OLT), that can meet the requirement of the stability ofbandwidth in ONUs and avoid the threaten of channel contention and bandwidthcontention.. The convergence of WSN and PON can effectively solve the problem thatsending the large-scale data into backbone network. Therefore, the research ofWSN/PON has a very important significance for us.In this paper, we first introduce the knowledge about queueing theory, knowabout some cases that queueing theory is applied in daily life, briefly introduce thegeneral WSN and PON architecture respectively. Then we also analyze the feasibilitythat applying queueing theory over the WSN/PON cluster-base network. Second, weconstruct a typical WSN/PON cluster-based network architecture, in this network,the cluster heads in WSN connect with ONUs in PON, the data collected by eachsensor node are sent into ONU through its cluster head, the splliter selectsappropriate path forward to OLT, then arrive at backbone network. According to thecharacteristics of queueing system in the network, we use a tandem M/M/1queueing model analyze the indexes that impact the network performance. By comparing the relationship among the performance indexes, we can obtain theoptimal value to configure the hybrid network. Then we discuss the energy functionsin cluster WSN, derive the relationship between the number of sensor nodes and theenergy of WSN. Taking consideration of the limited buffer space, channel contentionand the possibility of a link failure, we also derive the total average delay through aroute path. These research works are basic theory analysis about this hybrid network,they can help us to construct and configure the WSN/PON cluster-based hybridnetwork, and thus to optimal network performance and design more flexible androbust network protocols.At last, we summarize all of our research work in this paper, discuss theshortages in our analysis, and provide some problems that can be researched moredeeply.