Method and apparatus for remotely controlling and monitoring the use of computer software

Claims

What is claimed is:

1. A method of renting an application program for use on a customer computer, comprising the steps of:

encrypting a key module of the program, the program being inoperable without the key module;

storing the program in the customer computer;

retrieving the program when it is desired to run the program;

upon retrieval of the program, automatically decrypting the key module to permit use of the program; and

during use of the program on the customer computer, recording accounting data representative of the use to facilitate transactions based on the use.

2. The method of claim 1, further comprising the step of transmitting the accounting data to a central host computer at preprogrammed times.

3. The method of claim 2, further comprising the steps of:

monitoring the state of a time monitoring means connected to the customer computer, the time monitoring means for monitoring the use of the program; and

preventing the use of the program when the time monitoring means is disconnected from the computer.

4. Apparatus for renting computer programs comprising:

a rental control unit coupled to a rental computer and including first transmitting and receiving means for transmitting first type information to a user computer and for receiving second type information from said user computer, said first type information including at least one computer application program, said rental control unit also including encryption means for encrypting at least one preselected portion of said computer program to form an encrypted module before transmission of said first type information by said transmitting and receiving means, said encryption means including a first encryption key for use in forming said encrypted module, said encryption module being only a fraction less than one of said computer program; and

a user control unit coupled to a user computer and including second transmitting and receiving means coupled to said first transmitting and receiving means for transmitting second type information to said rental computer and for receiving said first type information from said rental computer, said second transmitting and receiving means including decryption means for decrypting said encrypted module to form a decrypted module, said user control unit also including storage means coupled to said decryption means for storing said decrypted module and transfer means for causing said decrypted module to be transferred from said storage means to said user computer for execution by said user computer and for removing said decrypted module from said user computer when execution by said user computer is completed.

5. Apparatus as in claim 4 wherein said encryption means includes a second encryption key for use in encrypting said first encryption key to form an encrypted first encryption key, and said decryption means includes a copy of said second encryption key for use in decrypting said encrypted first encryption key.

6. Apparatus as in claim 4 wherein said second type information includes time accounting data for determining rental charges for use of said computer program, said rental charges based at least in part on the length of time said decrypted module is being executed by said user computer.

7. Apparatus for controlling the use by a second computer of information stored in a first computer, said apparatus comprising:

first transmitting and receiving means coupled to said first computer for transmitting information to said second computer;

a second transmitting and receiving means coupled to said first transmitting and receiving means and to said second computer for receiving information transmitted by said first computer;

said first and second transmitting and receiving means each including encryption/decryption means for encrypting and decrypting, respectively, preselected portions of the information, said preselected portions including application program information, and a first encryption key for encrypting and decrypting said preselected portions of the information including, said application program information;

said first and second transmitting and receiving means each including a second encryption key for encrypting and decrypting, respectively, said first encryption key;

error detection means for detecting errors, on a block-by-block basis using a polynomial checker, in data transmitted from said second computer to said first computer and for producing an error signal representative thereof; and

retransmission means coupled to said error detection means and responsive to said error signal for producing a signal representing a request for retransmission of said data, said second transmitting and receiving means responsive to said request for retransmission for retransmitting said data.

8. Apparatus as in claim 7 further including monitoring means for monitoring usage by said second computer of the information transmitted to said second computer for developing time accounting data relative to rental charges for said usage, and for preventing usage of the information if said second transmitting and receiving means is disconnected from said second computer.

9. Apparatus as in claim 8 further including memory means coupled to said monitoring means for storing said time accounting data, said second transmitting and receiving means being responsive to a second command from said first computer for transmitting said time accounting data to said first computer.

10. Apparatus as in claim 7 wherein:

said encryption/decryption means in said second transmitting and receiving means decrypts the encrypted portion of the application program information only upon request of a user of said second computer to use the information, said second transmitting and receiving means thereupon transmits the decrypted information to said second computer.

11. Apparatus as in claim 7 further including:

error detection means for detecting the presence of an error in the information transmitted by said first transmitting and receiving means and for producing an error signal; and

retransmission means coupled to said error detection means and responsive to said error signal for producing a signal representing a request for retransmission of the information transmitted by said first computer, said first transmission and receiving means being responsive to said request for retransmission for retransmitting the information.

12. Apparatus as in claim 7 wherein said first and second transmitting and receiving means are coupled to each other via a public communication network.

13. Apparatus as in claim 12 wherein said first and second transmitting and receiving means each include connection means for connecting said first and second transmitting and receiving means, respectively, to said public communications means.

14. Apparatus as in claim 13 further including a telephone coupled to said connection means associated with said second transmitting and receiving means, said connection means including means for connecting said telephone to said public communications network when said second transmitting and receiving means is not receiving the information and said transmitting means is not transmitting said time accounting data.