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Unformatted text preview: hysically secured area, he/she inserts his/her electronic ca into the reader installed at the entrance of that area. The reader reads and checks the authorization data encoded on the card before permitting the individual to enter the area (the door is electronically linked to the reader and opens only if the reader finds that the individual is authorized to have access to the area). In such applications, the electronic-card reader is normally linked to a central computer, which maintains a record of who all entered or left secured area and at what time. In case of security breaches, this record is used to trace the problem. Depending on the manner in which data is encoded, electronic cards are of the following two types: 1. Magnetic strip cards. These cards have a magnetic strip on their back. The data to be encoded the card is stored on the magnetic strip. The magnetic strip of a card can contain much more data f unit of space than do printed characters or bar codes. Moreover, the data stored on the magnetic strip cannot be read visually. This makes them a perfect candidate for storing confidential data. 2. Smart cards. Smart cards have a built-in microprocessor chip instead of the magnetic strip. The data to be encoded on the card is permanently stored in the memory of the microprocessor chip. The memory of a smart card microprocessor can contain much more data than the magnetic strip of a magnetic strip card. Moreover unlike a magnetic strip card, a smart card also has some processing capability because its microprocessor has its own processor and memory. This feature attributes intelligence to smart cards and makes them more suitable for a wider variety of applications than magnetic strip cards. For example, a smart card can be used as a cash card by storing a specific amount of cash in the microprocessor chip before the card is issued to a customer. As and when the customer uses the card to make purchases, the amount of purchase made at every instance is deduct from the balance amount stored in the card by inserting the card in a card read/write machine (al called electronic registers) t...
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This document was uploaded on 04/07/2014.

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