same time, WSN is usually deployed in unattended maintenance, can not control the environment, besides the general wireless network facing the information disclosure, information tampering, replay attack, denial of service and other threats, WSN faces the sensor node easy for an attacker to physical manipulation, and get all the information stored in the sensor node, so as to control the part of the network threat. The user can not be accepted and deployed without a sensor network to solve the security and privacy issues, so in the WSN protocol and software design, should fully consider the security problem of WSN may face, and the safety mechanism is integrated into the system design. Only in this way, can promote the extensive application of sensor networks, otherwise, can only be deployed in Sensor Network Limited, controlled environments, the ultimate aim and sensor networks -- to achieve universal computing and become an important way of people's life is contrary.

The data link layer in the protocol stack usually provides two main services: media access control (MAC) and error control [3]. In a variety of MAC, carrier senses multiple accesses (CSMA) in ad-hoc sensor networks are the most commonly used. This is mainly because it is easy to implement, but more important is that it can improve the rate of channel multiplexing large network.

Wireless sensor nodes by multi-hop forwarding, through the access network gateway node, management, classification, processing of sensory information in the task manager node network, then the sensing information to the application user. Sensor nodes first acquisition such as  sound, light and distance environment related data, and these data are sent to the gateway node simple processing. Wireless sensor networks usually have two kinds of application modes: active polling mode, passive mode. Active mode requires the gateway node active polling for each sensor nodes to get the news, while passive mode requires that in the event of a sensor node occurs, the gateway node can be timely response. Each sensor node data can be combined, which greatly improves the efficiency of sensor network. Of course, this also requires sensor nodes to computing ability, as is shown by equation 1.

collecting and processing information in the network coverage, and released to the observer sensor, object perception  and  observation.  The  paper  put forward

development novel organization structure of wireless sensor network protocol based on ZigBee technology.

2. Structure of Wireless Sensor Network Protocol Analysis

Sensor network deployment of large-scale networks in complex environment, real-time data acquisition  and  processing  brings  hope.  But  at the

In view of the environment and structure state monitoring, we design a universal wireless sensor network hardware platform; the hardware platform is composed of a number of sensor nodes, Sink nodes with wireless receiving function and a computer. Wireless sensor nodes distributed in the monitoring area, performing data acquisition, processing and wireless communication, Sink node receives the sensor data to the wired way and sends the data to the computer.

The design goal of traditional MAC protocol is to maximize throughput, minimize the delay and fairness. About MAC layer protocol  for  WSNs design is to minimize the energy consumption, which determines that it should be appropriate to reduce the throughput and delay. Because the  WSNs node always cooperates to complete an application task, so the usual fairness is not the main problem. In addition, some typical WSNs application also proposed is different from traditional wireless network design requirements for the MAC layer protocol. ZigBee技术无线传感器网络英文文献和中文翻译(2):http://www.chuibin.com/fanyi/lunwen_206557.html