User's Manual

ACG HF Multi ISO RFID Reader V1.0
ACG Identification Technologies GmbH 123
The Application can and should provide more barriers:
• Sector access conditions. It is possible to assign access conditions in a way
that only decrementing of values is allowed with the keys used in the field. So
even a manipulated field station cannot be used to increment the value on the
cards. As a general rule, key A is used as a field key, allowing only to read
and decrement values, and key B is used to format the card or increment
values.
• Diversified keys. To make life even harder for attackers, keys can be modified
using the serial number and memory content of the card. So each card uses
different keys and a listening attack on the reader interface would be
hopeless.
• Limiting cash volume stored on a card
• Do not use the transport keys (keys programmed at the time of delivery) for
ticketing applications!
• Ciphered and scrambled data storage
• Sabotage alarm
• Even higher security with contact less controller cards like DESFire, mifare
®
ProX, mifare
®
Smart MX etc.