User's Manual

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The Password can also be re-programmed, even if you do not know the previous one. In this case, however, the
contents of the data memory (Secure Data) are automatically reset.
7.4 Secure Data register: the data of the non-volatile memory
The Secure Data register is a non-volatile memory inside the dongle, which can be accessed only if you know the
Password. If you control the contents of the register, you are shown if an attempted 'break-in' is concerned, or lawful
installation of the software.
Model Memory
FX Parallel/USB 0
PR, EP Parallel/USB 64
PR, EP USB Driver Less 128
SP Parallel 416
SP USB 896
XM USB 8192
NET Parallel/USB 416
Table 5
SmartKey memory size
The Secure Data intervene in different ways in the protection mechanism, but mainly through an operation that
compares the expected contents with the contents effectively read by the dongle: the result of the comparison enables
you to decide whether or not to continue execution of the program.
In the case of the SP, XM and NET dongles, the register is also used for storing the user-programmable security
algorithm. Lastly, with the NET network dongle, some bytes are used to define the maximum number of simultaneous
users of the protected program and any limitation of the total number of executions. The license management register
requires 2 bytes for enabling the service, and 3 bytes for each protected program.
The Secure Data can be read or written from software providing the correct Password is first transferred.
If the Password is incorrect, the reading operations do not get the content of the Secure Data, but a pseudo-random
series of bits. Writing operations with an incorrect Password have no effect, in order not to alter the valid content of
programmed data.
7.5 Fail Counter register: the incorrect accesses alarms
The Fail Counter register, available in the EP, SP, XM and NET dongles only, enables automatic counting of the
number of incorrect access attempts to the dongle.
Whenever a read or write access with an incorrect Password is attempted, the content of the register is automatically
increased by one.
This is therefore a counter that is automatically incremented for reading only, and indicates 'break-in' attempts by a
search of the Password. For reasons of security, the counter cannot be reset by any of the dongle's writing or
programming functions.
Counting is in the range from 0 to 10,000. The register is read during a READING MODE, subject to knowledge of the
Password. If the Password is incorrect, the returned number is randomly generated.
The software to be protected can use the register for verifying any unlawful access attempts. For example, if the dongle
is used to permit access to the databanks or confidential data, the software can permanently disable it by altering the
content of the Secure Data, after a programmed number of incorrect access attempts (including non-consecutive
attempts).