Based on radio frequency identification technology online-access control system design (1)

1. introduction

In digital technology, the rapid development of network technology, the access control technology has been developing rapidly.

Access control system already goes beyond the mere doorway and key management, it has gradually developed into a comprehensive access control system. Access control system development in the wake of a single password for keyboard access control system, IC card entrance guard system, contactless IC card entrance guard system, and now the latest biometric access control system. Non-contact IC card entrance guard system because its technology is mature, affordable, easy-to-use, superior performance, has been widely used. A conservatory piano room 14 storey building 300 piano room, has been adopted by the management approach is a student at the piano room Management Center registration reception for the key using the piano room. This management approach there is a lot of drawbacks, such as Student Union secretly with piano room key so you do not register through the the piano room Central Administration uses the piano room without permission, or leave the keys in the returned students cannot guarantee that the piano is no one in the room. But the piano room equipment expensive millions is difficult to determine if there is damage, damage to school property security risk. Therefore to the piano room management creates certain difficulties. In order to reach the piano room scientific and efficient management, this article offers an on-line type of access control system design to whole floor piano room for centralized control and centralized management.

2. system structure

This article from the National Natural Science Foundation of China (number: 60472044) and Beijing University of young teachers in natural science research fund (number: QN0518) funding.

System using hierarchical distributed centrally control programmes, will all access control reader to form a distributed network, its composition as shown in Figure 1.

The entire system including the Central Administration Server, floor PC, access control reader three hierarchies.

Central Administration Server for the entire access control system of management and control center, at the same time run a piano room management system programs and databases.

The database used to support network communications, database structure, easy for function extension. In order to achieve all the piano room for unified management purposes, the use of the piano room students with student card in the control center through the the piano room management system registration and allocation of the piano room and student personal information into the database. Use to control center through the the piano room management system returned to the room to attendance and queries. Through the management system that can clear the query to each room use, records, etc.

Floor PC that access control service, is responsible for access control reader and a bridge between Central Administration Server.

Access control service program for data forwarding function, realization of the RS485 and TCP/IP communication protocol conversion, itself does not directly control access control reader. Up through a local area network with the TCP/IP protocol to communicate with the Central Administration Server, passing the door card reader of the credit card request and the Central Administration of the various control commands to the server. Down by 485 through round homing mode and access control reader interaction information. Records from the access control reader acquisition time of data collection, such as

　　

Figure 1 system chart

Fruit long cannot and Central Administration server address, the time to drop off obsolete card data.

Access control service only with the background data exchange and forward functions, apart from the process is started and stopped, and the user interaction information, design as a Windows system service process is running, without the need for interaction design and user interface, only run the log file.

3. access control reader design

System to students of non-contact IC card card as a system user card, contactless IC card is based on the principle of electromagnetic induction, simply place a card in the access control reader induction zone will be able to realize the data exchange, without any contact, use a very convenient, fast, and difficult to damage.

Therefore in the public transport, access control, campus, enterprises and personnel management has a wide range of applications. PHILIPS Mifare card companies are now non-contact IC card mainstream products, their typical model for Mifare S50 1, it has to hold the EEPROM 1K, divided into 16 sectors, each sector has its own separate password, complete security, enable Mifare1 S50 has a smart card. Mifare card is a smart card (smart card), with central microprocessor (MCU) and ASIC, etc. for its security confidentiality, authentication logic, arithmetic operations, such as micro-operation control in an orderly manner [1].

1. the principle of work

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