Method for using communication channel round-trip response time for digital asset management

• US 20040098583A1
• Filed: 11/15/2002
• Published: 05/20/2004
• Est. Priority Date: 11/15/2002
• Status: Active Grant

• Current Assignee: Cable Television Laboratories Incorporated
• Original Assignee: Cable Television Laboratories Incorporated
• Inventors: Weber, Joseph W.
• Granted Patent: US 7,398,392 B2
• Time in Patent Office: Days
• US Class Current: 713/168
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management data processing systems or methods, specially adapted for commerce, e.g. marketing, shopping, billing, auctions or e-commerce G06Q30/00
• CPC Class Codes: H04L 63/0492 by using a location-limited connection, e.g. near-field communication or limited proximity of entities
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: H04L 63/10 for controlling access to devices or network resources
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal

Abstract

The present method for using communication channel round-trip response time for digital asset management utilizes a predetermined distance between a sending device and a receiving device to prevent unauthorized receipt of digital content when the unauthorized receiving device is located beyond the predetermined distance. When the receiving device requests digital content from the sending device, the sending device replies with a request for an acknowledgement. The receiving device sends the requested acknowledgement. The time between sending the request for an acknowledgement and receipt of the acknowledgement is the actual round-trip response time. The actual round-trip response time is compared to a predetermined response time limit for the predetermined distance and if the actual response time is within the predetermined response time limit, the request for digital content is granted and if the actual round-trip response time is not within the predetermined response time limit, the request for digital content is denied.

Claims

1. A method for preventing distribution of digital content to a receiving device located within a predetermined distance of a sending device, the method comprising the steps of:

at said sending device, receiving a request for digital content from said receiving device;

in response to receiving said request, requesting an acknowledgement from said receiving device;

in response to receiving said request for said acknowledgement, sending said acknowledgement to said sending device;

in response to receiving said acknowledgement at said sending device;

determining an actual round-trip response time for said request for said acknowledgement; and

using said actual round-trip response time to determine if said receiving device is located within said predetermined distance of said sending device.

2. The method of claim 1 wherein the step of requesting an acknowledgement from said receiving device further comprises:

substantially simultaneously to requesting said acknowledgement, recording a first time representing when said request for said acknowledgement was sent.

3. The method of claim 2 wherein the step of receiving said acknowledgement further comprises:

substantially simultaneously to receiving said acknowledgement, recording a second time representing when said acknowledgement was received at said sending device.

4. The method of claim 3 wherein the step of determining a round-trip response time comprises:

comparing said first time and said second time to determine said actual round-trip response time.

5. The method of claim 1 wherein said step of using said round-trip response time further comprises:

comparing said actual round-trip response time to a predetermined response limit representing said predetermined distance, wherein if said actual round-trip response time is within said predetermined response limit, said request for digital content is granted and if said actual round-trip response time is not within said predetermined response level, denying said request for digital content.

6. A method for detecting a request for digital content from an unauthorized receiving device, the method comprising the steps of:

establishing a predetermined reference between a sending device and an authorized receiving device, said predetermined reference having a corresponding predetermined response time;

receiving said request for digital content at said sending device from said unauthorized receiving device;

in response to receiving said request for digital content, sending a request for an acknowledgement to said unauthorized receiving device;

in response to receiving said request for acknowledgement, sending said acknowledgement to said sending device;

in response to receiving said acknowledgement at said sending device, determining an actual round-trip response time; and

comparing said actual round-trip response time to said predetermined response time, wherein if said actual round-trip response time exceeds said predetermined round-trip response limit for said authorized receiving device, said unauthorized receiving device is not authorized to receive said digital content.

7. The detection method of claim 6 wherein the step of sending a request for an acknowledgement further comprises:

substantially simultaneously to requesting said acknowledgement, recording a time representing when said request for said acknowledgement was sent to said receiving device.

8. The detection method of claim 7 wherein the step of receiving said acknowledgement from said receiving device further comprises:

substantially simultaneously to receiving said acknowledgement, recording a receive time representing when said acknowledgement was received at said sending device.

9. The detection method of claim 7 wherein the step of determining an actual round-trip response time comprises:

calculating a difference between said send time and said receive time to determine said actual round-trip response time.

10. The detection method of claim 6 wherein the step of determining an actual round-trip response time comprises:

calculating a difference between sending said request for said acknowledgement from said sending device and receiving said acknowledgement at said sending device.

11. A method for preventing distribution of digital content from a source device to an unauthorized destination device located outside of a predetermined geographical area, the method comprising the steps of:

receiving a request from a destination device for said digital content from said source device;

in response to receiving said request for digital content, requesting an acknowledgement from said destination device;

substantially simultaneously to sending said request for said acknowledgement, recording a first time denoting the time that said request for acknowledge was sent to said destination device;

in response to receiving said acknowledgement request from said source device, sending an acknowledgement from said destination device to said source device;

receiving said acknowledge at said source device from said destination device;

substantially simultaneously to receiving said acknowledge at said source device, recoding a second time denoting the time that said acknowledgement from said destination device was received at said source device;

calculating a difference between said first time and said second time to determine a round-trip response time; and

comparing said round-trip response time to a predetermined response limit representing said predetermined geographical area, if said round-trip response time exceeds said predetermined response limit, denying said request for digital content and if said round-trip response time does not exceed said predetermined response limit, granting said request for said digital content.