Copyrighted software may be executed only on an authorized computer by
using a protection mechanism to restrain software to a designated machine.
The protection mechanism includes a CIN (Computer Identification Number)
reader and a CIN verifier. The CIN reader comprises a function call which
reads CINs from the computer where the copyrighted software is intended to
execute, and a converter which converts CINs to encrypted CINs. The CIN
verifier comprises the encrypted authorized CINs and logic. The CIN may
comprise the serial number of a computer chip, the serial number of a hard
disk, the serial number of a computer operating system or the like.
Protection mechanisms may be integrated into the copyrighted software at
stop points by compiling the software source code or revising the
executable code of the software. When the resulting protected software is
processed on a computer, the protection mechanisms are executed at the
stop points. The CIN verifiers then compare the encrypted authorized CINs
with the encrypted read-in CINs. If the comparisons of the encrypted CINs
match, the copyrighted software continues running. However, if the
encrypted CINs are different, the protected software stops running and
sends out a warning message.