Transferring media files between users after encrypting with encryption key obtained from a digital rights management server

Patent metadata

Field	Value
Publication number	US-10289809-B1
Application number	US-78136510-A
Country	US
Kind code	B1
Filing date	May 17, 2010
Priority date	May 17, 2010
Publication date	May 14, 2019
Grant date	May 14, 2019

Abstract

A method is disclosed for transferring a media file from a first user device to a second user device. The first user device receives a first media file, and receives a first digital rights management (DRM) license from a DRM server corresponding to the first media file. The first user device encodes the first media file into a second media file using the first DRM license, and transfers the second media file to the second user device.

First claim

What is claimed is:

1. A method of transferring an encrypted media file from a first user device to a second user device and to a third user device, the method comprising:
by the first user device:
receiving a first media file encoded using a first encryption key;
receiving a first digital rights management (DRM) license from a DRM server, the first DRM license including a first DRM license key for encoding the first media file and a first decryption key for decoding the first media file, the first DRM license key being different than the first encryption key used to encode the first media file;
encoding the first media file into a second media file using the first DRM license key of the first DRM license, the first decryption key of the first DRM license being not operable to decode the second media file;
transferring the second media file to the second user device and causing the second user device to request a second DRM license including a second decryption key associated with the first DRM license key, the second decryption key operable to decode the second media file for playback;
obtaining a first credit in response to the second user device requesting the second DRM license; and
obtaining a second credit that is less than the first credit in response to:
the second user device transferring to the third user device a third media file, the third media file comprising the second media file encoded with a second DRM license key of the second DRM license, and
the third user device requesting a third DRM license configured to decode the third media file;

by the second user device:
receiving the second DRM license from the DRM server, the second DRM license including the second DRM license key for encoding the second media file;
encoding the second media file into the third media file using the second DRM license key of the second DRM license;
transferring the third media file to the third user device, and causing the third user device to request the third DRM license including a third decryption key associated with the second DRM license key, the third decryption key operable to decode the third media file for playback; and
obtaining a third credit in response to the third user device requesting the third DRM license, wherein the third credit is greater than the second credit; and

by the third user device:
transmitting header information for the third media file to the DRM server, the header information for the third media file identifying the first user device and the second user device,

wherein values of the second credit and the third credit are determined based on the header information for the third media file.

2. The method as recited in claim 1 , further comprising:
by the first user device:
decoding the first media file using the first decryption key of the first DRM license; and
playing the decoded media file.

3. The method as recited in claim 1 , further comprising, by the first user device, transmitting to the DRM server an identifier identifying the second user device.

4. The method as recited in claim 1 , further comprising:
by the second user device:
receiving the second DRM license from the DRM server;
decoding the second media file using the second decryption key of the second DRM license; and
playing the decoded media file.

5. The method as recited in claim 4 , further comprising, by the second user device, transmitting header information for the second media file to the DRM server, wherein:
the header information for the second media file identifies the first user device; and
a value of the first credit is determined based on the header information for the second media file.

6. The method as recited in claim 1 , wherein the header information for the third media file further identifies the third media file.

7. A digital rights management (DRM) server comprising:
means for receiving from a first user device a first request associated with at least one of playing a first media file encoded using a first key or transferring media data of the first media file to a second user device;
means for, in response to the first request, transmitting to the first user device a first DRM license including a first DRM license encryption key to encode, by the first user device, the first media file into a second media file, the first DRM license further including a first decryption key to decode the first media file, the first DRM license encryption key being different than the first key, and the first decryption key of the first DRM license being not configured to decode the second media file;
means for receiving from the second user device a second request associated with at least one of playing the second media file or transferring the media data to a third user device;
means for, in response to the second request, transmitting to the second user device a second DRM license including a second decryption key associated with the first DRM license encryption key, the second decryption key configured to enable the second user device to decode the second media file;
means for receiving from the second user device a first header associated with the second media file, the first header identifying the first user device;
means for determining an amount of a first credit based on the first header;
means for providing to the first user device the first credit in response to the second user device requesting the second DRM license;
means for providing to the first user device a second credit smaller than the first credit in response to receiving a request from the third user device for a third DRM license configured to decode a third media file transferred to the third user device by the second user device, the third media file comprising the second media file encrypted with a second DRM license encryption key of the second DRM license, wherein the second DRM license encryption key is configured to enable the second user device to encode the second media file into the third media file to transfer the third media file from the second user device to the third user device;
means for, in response to receiving from the third user device a request for playback of the media data, transmitting to the third user device the third DRM license including a third decryption key associated with the second DRM license encryption key, the third decryption key configured to permit the third user device to decode the third media file to play the media data on the third user device;
means for providing to the second user device a third credit in response to the third user device requesting the third DRM license, wherein the third credit is larger than the second credit; and
means for receiving from the third user device a second header associated with the third media file, the second header identifying the first user device and the second user device,
wherein amounts of the second credit and the third credit are determined based on the second header.

8. The DRM server as recited in claim 7 , further comprising means for receiving an identifier from the first user device identifying the second user device.

9. The DRM server as recited in claim 7 , further comprising:
means for receiving from the second user device data identifying the first user device as originator of the second media file; and
means for generating the second DRM license including the second decryption key in response to determining that the data identifies the first user device as the originator of the second media file, the second decryption key further configured to permit the second user device to decode the encoding of the second media file performed by the first user device with the first DRM license encryption key included in the firs

Assignees

• Hesselink Lambertus
• Western Digital Tech Inc

Inventors

• Hesselink Lambertus

Classifications

• G06Q20/1235

  with control of digital rights management [DRM] · CPC title

• G06F21/10 Primary

  Protecting distributed programs or content, e.g. vending or licensing of copyrighted material (protection in video systems or pay television H04N7/16) {; Digital rights management [DRM]} · CPC title

• H04L9/088

  Usage controlling of secret information, e.g. techniques for restricting cryptographic keys to pre-authorized uses, different access levels, validity of crypto-period, different key- or password length, or different strong and weak cryptographic algorithms (network architectures or network communication protocols for using time-dependent keys in a packet data network H04L63/068) · CPC title

• H04N21/2541 Primary

  Rights Management (protecting software against unauthorised usage in a vending or licensing environment G06F21/10; security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08) · CPC title

• H04N21/4627

  Rights management {associated to the content (security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08)} · CPC title