Research And Implementation Of AN Application Platform For The Internet Of Things Based On 6LOWPAN

In recent years, technology about the Internet Of Things has become popular at home and abroad. It is one of the important branches and key technologies of the Internet Of Things that connecting IP wireless sensor network to the Internet. 6LoWPAN which combines IPv6 with the IEEE 802.15.4 protocol is one of the most popular focus. This paper focus on designing and implementing an application platform for the Internet Of Things based on 6LoWPAN to provide a model of application platform for the industry. The design of the platform's hardware and software is to meet the principle of versatility and expandability as much as possible, in order to make it be suitable for more scenarios.This paper refers to existing application model of the Internet Of Things, and proposes a network architecture of application platform based on 6LoWPAN for the Internet Of Things. Implementation of hardware and software is divided into four main parts containing terminal, network, gateway and application.First, a multifunctional monitoring terminal of the Internet Of Things has been successfully developed, which achieves the object of sensing information and intelligent control. ATmega64 microprocessor plays the role of control core of the terminal which integrates a total of six sensors for temperature, humidity, combustible gas, flame detection, infrared body and noise sensors detection respectively, implements controlling the switches of five electrical equipment simultaneously by reforming circuit distribution box using electromagnetic relay, reads frequency identification tag number using RFID reader through serial port and configures the LCD screen to display sensing parameters in real time. Hardware design utilizes the PCB design concept of separating functional modules, and there is no doubt that it is the original PCB design of monitoring terminal and multi-parameter sensor module. Two kinds of data format for the application layer protocol is designed, including twelve bytes of perceptual information and four bytes of control signal. software implementation uses C language programming under the AVR Studio IDE (Integrated Development Environment), achieving the object of perception information collection and packet encapsulation, control signal reception and analysis. Monitoring terminal of the Internet Of Things and 6LoWPAN terminal nodes exchange data by serial port.Secondly, 6LoWPAN network is built as star network topology referencing to principle of 6LoWPAN protocol. Hardware implementation uses CC2430 RF chip in accordance with IEEE 802.15.4 to complete the hardware design of network nodes, end nodes and the central node conform to the method of two-MCU architecture which separates the network function and application function. 6LoWPAN terminal nodes connects with PCB backplane of monitoring terminal by double pin way, and interact by UART mode. 6LoWPAN central nodes communicate with embedded gateway of the Internet Of Things through serial port. Software implementation which is based on the TinyOS embedded operating system development utilizes NesC language to complete programming, implementing the main functions of 6LoWPAN adaptation layer, transmission of UDP packet from end to end and wireless communication of perceptual information control signal.Then, an ARM9-based embedded gateway of the Internet Of Things is designed and implemented, it has functions not only for 6LoWPAN network to access Internet, but also for monitoring and managing of the Internet Of Things. The gateway takes embedded development platform whose core is ARM9 S3C2440 chip as its hardware environment, and transplants the embedded Linux operating system with kernel version 2.6.32.2 as its software development environment. Upon completion of protocol conversion, one hand, the gateway configures the Qt/Embedded GUI operating environment, and successfully develops Qt GUI for monitoring and managing the Internet Of Things. With the interface, users can have real time on-site control capability for monitoring and managing the Internet Of Things by operating the LCD touch screen. On the other hand, it becomes true for users to monitor and manage the Internet Of Things through accessing web with PC terminal, smartphone and so on, which is based on the work this paper implements that contains transplanting the Thttpd embedded Web server, developing Web applications based on Ajax and CGI programing. In addition, multi-process synchronization mechanism based on the named pipe FIFO is designed to ensure that Qt GUI and the Web applications can interact data with the 6LoWPAN network in real-time.Finally, based on the realization of the application platform, communication distance of the 6LoWPAN nodes and transmission connectivity of the object's perceptual information and control signal is completed, and the three test results are available. This paper provides an application example named "Smart Lab" based on the application platform for the Internet Of Things which is implemented by work stated as above, and then makes a brief summary for the platform adapting to other scenarios.