| 摘要 |
<p>The present invention consists of an electronic device and a software system which goes beyond the functions and limits of the known protection systems (electronic keys), making it practically impossible not only to duplicate programs but also to use them other than within the periods and in the ways specified by the licence. A program can therefore be enabled for a certain number of functions, and the user cannot overcome this by making a new physical copy of the program or by making an exact copy of the protection card; in the prior art, however, any protection system can be evaded by exactly duplicating the software bit by bit, and if necessary the corresponding hardware. The present invention overcomes these limits and also enables software, hardware, goods and services to be leased in a secure way. Another characteristic of the present invention is the possibility of use as a protection and antidote against software viruses which is physically and theoretically secure and definitive, even when used against future viruses which are not yet known, or fortuitous accidents which cause loss and damage to software. <IMAGE></p> |
