Research On Embedded Internet Based Automatic Meter Reading System And Its Security Issues

Automatic Meter Reading Systems read, process and manage data automaticly for meters by using electronics, computer and networking technologies. With AMR, the traditional manual meter reading shortcomings can be overcomed, so it appeals to users and energy management department. This paper focuses on AMR research, and the main contents in this paper include:(1) After analyzing the development of AMR, an architecture of the AMR system based on embedded Internet technology is designed. The merits and demerits of three proposed AMR solutions are compared, and it is pointed out that accessing Internet directly, reading and managing data automaticly over Internet for meters is the trend of AMR systems. Then the key technologies to implement and popularize this solution are concluded.(2) For the Internet access module of AMR system, a low-cost 8-bit MCU is selected and the structure of the module is confirmed when functions, cost and other factors are taken into account. The TCP/IP protocols subset to be implemented at every layer is selected according to the characteristics and demands of AMR system. Then an embeddedTCP/IP protocols stack is implemented on 8-bit MCU. This Internet access technology reduces the cost of Internet access and satisfies the low-cost need of AMR systems.(3) The network security issues in AMR system is surveyed, and consulting a general security architecture design method, a comprehensive security architecture is proposed according to the system characteristics.(4) According to the AMR system characteristics, especially, the large distinctions of software and hardware between data management subsystem and data acquisition subsystem, AMRSCP, Automatic Meter Reading system Secure communication protocol is designed. This protocol is based on symmetric-key encryption scheme with a main pre-shared symmetric key and an updating session key, and it provides security sevices on identity authentication, data confidentiality and data integrity. Using this protocol, a customized secure communication scheme for subsystems is set up. At last, the requests and best choices of cryptographic algorithms is concluded.