The first chapter system design
1, smart card system and network structure
The 1.1 system.
Smart card system network mainly consist of: eachapplication subsystem workstation card center dataserver, and each sub system terminal. Including business card subsystem: dining room, bathroom, water charges,library, computer control, supermarket, attendance,access control. The terminal comprises: distributing terminal, terminal, terminal fees, deposit water control terminal, terminal module, attendance, access controlterminal.
Smart card system network structure is divided into two layers, the first layer is the backbone to card database server as the center, using TCP/IP communication protocol, the layer can be connected to the various subsystems of the workstation, the prepositive machine,transfer machine and multimedia query machine. The second layer is composed of RS485 communicationnetwork workstation control subsystems, machine through the 485 communication card real-time control eachterminal operation for workstations using PC of the layer network, collecting the transaction recorded and reported to the card server.
1.2 card network
According to the business card Park building layout based on existing line pipe, and for safety considerations,with the formation of the smart card system sub networkscheme:
(a) in the future, the establishment of the enterprisebackbone network in a card network, all the computercard system all access this online, so as to separate cardnetwork and enterprise network logic, technology to ensure the security of the smart card data.
(two) in the second layer application subsystem isindependent of the RS485 network, RS485 network using the shielding two core twisted pair, as long as the use ofthe existing pipeline infrastructure, or in each subsystemto be related to the RS485 network for pipelineconstruction, specific to each subsystem separately wiring. The following RS485 lines need cloth place: theapartment, canteens, supermarkets.
(three) the establishment of a web server between thecard network and enterprise network, enterprise network web server is connected with the card network, which can guarantee the enterprise network can access cardnetwork, but also ensure the safety card network internal data.
Card database server placed in the business cardnetwork center machine room, convenient network management and maintenance, a room on the first floordining room set up card issuing center, implementation,management, monitoring, issuing settlement, query and other functions. The other subsystems workstation placed in their respective places, in order to facilitate themanagement
1.5 system features
1, scalability. Because the system uses the server,workstation mode, each subsystem can be extended according to the workstation to increase or decrease, the actual needs; no restriction on the number of terminals,the system according to the business development andincrease the number of arbitrary terminals; to adapt to the rapid expansion of enterprise scale, the database used in this system is SQL SERVER2000 database, its capacityfor tens of thousands of enterprises, the scale of the enterprise.
2, cross enterprise zone card design, data businessdistrict can be timed switch. The company developed thecross enterprise zone card design, reserved space for Liu Guojun in many enterprises vocational business district development. Card Center data server settings in the newbusiness district, sub district and business districtenterprises set up the server, can exchange data throughnetwork or network timing and server; the subsystem ofeach enterprise zone and workstation server, exchange data through network communication. The data for CRC enterprise posterior using DES encryption to ensure data integrity and security. Implementation of multi areacentralized management of enterprises, a common card,partition settlement.
3, black and white list mechanism. Report of lossworkstation will loss record as the black list to send abroadcast to all terminals. When the terminal is in offlinemode, automatically to the black list in the table to check.White list is effective for online transaction authentication card, to prevent business card is illegal crack. Black listcan store 200000, we use direct addressing positioningalgorithm, terminal without one one compare in the search list, can directly remove the black list, so when theblack list increases terminal not slow.
4, online transaction. When the 485 line is normal, the system automatically in online transaction state, using similar bank card transaction mode, when the terminalafter the credit card account, immediately request data to the workstation, the workstation to verify the validity of the card, to ensure the safety of the business card data, iffound invalid card freezing the account immediately. If the event business card has been cracked electronic wallethas been modified, we can easily identify and freeze theaccount.
5, the offline normal use. There are two types of offline, is the enterprise network workstation and server connectionfailure, causing subsystem workstation off network; two is the RS485 network fault, resulting in the offline between workstations and terminals. Line fault cause for a variety of reasons, the terminal can realize offline normal operation, the unit can still work normally. Offline terminalautomatically use the card on the electronic wallet function, when the line is smooth, uploading transaction data.
6, immediate loss, multi point loss. Due to the use of theon-line transaction mode, so the loss of operation is quite simple, just set a loss report flag can account for therecords in a database. Instant can take effect.
7 subsidy system, convenient and quick. In the businesscard to give subsidies directly to the data into thedatabase table account, we can realize the benefitsimmediately in the business card. The user need not tospecify one one for credit card machine.
8, multiple charging mode. Can use cash, bank transfer,automatic recharge bulk transfer mode.
9, to close synchronization mechanism. Because the Mifare1 card capacity is larger, the last 20 transaction records the card on a card, when offline data not uploadterminal or damaged card account does not match the situation, we use the mechanism of synchronous checkbusiness card and database, timely correction cardamount.
10, the server disk array. The data on the server diskarray, both to expand the storage capacity, but also improves the storage speed, enhances the fault tolerance, but also can use two groups of hardsynchronization is complete image storage, to ensure the security of data
2, card selection
Contactless smart card 2.1 Mifare
We recommend the use of Philips's Mifare 1 contactless smart card as a business card, Mifare 1 has been in themiddle and Primary School of enterprises are widely used, the fact proved successful. Non contact interfacestandards have been developed to international standards of RF card standard MIFARE RF RF, sensing distance up to 100mm, fully realize non-contact reading and writing; data preservation period up to 10 years, and the card anti electrostatic protection capacity of more than 2KV; the card data reading and writing more than 100000; reliability and anti interference strong ability.Mifare 1 cards in the communication security on the use of three transformer enterprises in line with ISO9798 international standard test technology, the legitimacy ofcard read-write device and the mutual businessexperience, in order to ensure its safety; Mifare 1 serial number is the only global manufacturer, before the products leave the factory has the sequence number in the chip., do not change. Card with storage capacity of 8Kbit is divided into 16 sectors, each sector is divided into4 blocks, each sector by the password managementmodes, a Caddo dense, can realize a plurality of electronic wallet function.
2.2 card design
Business card can be designed for Portrait card, bar code card, radio frequency card (Mifare 1) three in one combination cards, card base material is PVC, beautiful,generous, durable. The business card is not only the staffcard, is a card, but also can realize business cardconsumption (dining hall, computer room, shopping,bathing fee, access validation, books borrowing,attendance management) and the query (registration,query results, card consumption query, query and othergoods receipt). The following scheme for selecting reference:
* card printed logo pattern.
* positive by card printer staff photos, ID, name,Department, class and other information.
* back printing the card using the rules and precautions,such as bar code printing workers.
