Playback Device Key Segmentation for DRM Security

Solution Overview

Problem

Current conditional access and Digital Rights Management systems for digital video transmissions face challenges in securing communications and preventing unauthorized access to multimedia content, particularly in ensuring that non-essential modules do not circumvent essential playback processes.

Innovation Solution

The method involves generating a key base and key contribution using a rights management server, which are then sent to a playback device to be processed by separate modules, ensuring that all modules must execute in order to achieve playback, thereby securing communications and preventing unauthorized access.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional encryption and key distribution systems are used, then content security is maintained, but control modules can be circumvented and non-essential functions can bypass essential playback processes

Engineering Contradiction:

Improvecontent securityVSAvoidkey management complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The decryption key is segmented into two components: a key base and a key contribution. The key base is provided to the decryption module while the key contribution is provided to the control module. Both components are necessary to reconstruct the full decryption key, ensuring that neither module can function independently without the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A rights management server acts as an intermediary that generates and distributes both the key base and key contribution to the playback device. This intermediary ensures that the key components are properly distributed and that the control module must execute its functions to provide the necessary key contribution for decryption.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Adaptability or versatility

If control modules are made optional for playback, then device functionality and adaptability are improved, but security is compromised as non-essential modules can be bypassed

Engineering Contradiction:

Improvedevice functionalityVSAvoidplayback security

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The decryption key is segmented into two components: a key base and a key contribution. The key base is provided to the decryption module while the key contribution is provided to the control module. Both components are necessary to reconstruct the full decryption key, ensuring that neither module can function independently without the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system preemptively prevents circumvention by structuring the key distribution so that the control module's key contribution is required before decryption can occur. This preliminary security measure ensures that even if the control module is non-essential for playback functionality, it becomes essential for key reconstruction and thus for content access.

Inventive Principle:

Principle #9Preliminary anti-action

3Ease of operation

If key distribution is simplified, then ease of operation is improved, but security against unauthorized access is reduced

Engineering Contradiction:

Improvekey distribution simplicityVSAvoidaccess security

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The decryption key is segmented into two components: a key base and a key contribution. The key base is provided to the decryption module while the key contribution is provided to the control module. Both components are necessary to reconstruct the full decryption key, ensuring that neither module can function independently without the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A rights management server acts as an intermediary that generates and distributes both the key base and key contribution to the playback device. This intermediary ensures that the key components are properly distributed and that the control module must execute its functions to provide the necessary key contribution for decryption.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentEP3207659B1Securing communication in a playback device with a control module using a key contribution

Publication Date: 2021.03.10 VERIMATRIX INC

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AI summary

Systems and methods for securing communications in a playback device using a key base and at least one key contribution in accordance with embodiments of the invention are disclosed. In one embodiment, a process includes generating a key base using a decryption key and at least one key contribution, where the decryption key can be recovered using the key base and the at least one key contribution, receiving the key base, receiving the at least one key contribution, sending the key base to a decryption module, sending the key contribution to a control module, performing a control feature on the piece of content using the control module, providing the key contribution to the decryption module when the control feature is performed, generating the decryption key using the key base and the at least one key contribution, and accessing at least a portion of the piece of content.