Wireless Sensor Networks(WSNs), as one of the most important techniques in the 21st century, receives auniversal attention to the research on its key techniques.A solution is urgently expected to meet thehigher-quality service requirements of various applications on the limited bandwidth of wireless networks.Based on the ideas of Priority-based polling transmission with high-efficiency, and dynamic self-adaptation to loading, this paper presents a new analysis model of MAC Scheme of wireless sensor networks, which has made possible the Cluster Header capable of differentiating the nodes of different priority levels under mixed services policy and which has improved the flexibility and adaptability of the system via adjustment of the switch-in service in three time of load change input. The theoretical model of this protocol is established with Markov chain and probability generating function. Mathematical analysis is made on the mean queue length and the mean inquiry cyclic time of the common queue and the key node. It turns out that the findings from theoretical analysis correspond well with those from simulated experiments.

With the popularity of network, web is becoming one of the most effective ways in information sharing. However, with the increase of clicking index, a high-function server can hardly meet the increasing demand for service. This thesis provides the schedule strategy in the asynchronous mechanism of multiqueue double servers polling, which is conducted based on theory of polling multi-access and simulation experiments on computer, along with consideration to the load features of Web. It concludes that this strategy enables Web server to take on the features of good extendibility, utility and function.