Selective Message Exclusion in End-to-End Encrypted Group Chats
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current messaging applications lack the ability to selectively exclude recipients from an end-to-end encryption enabled group chat without compromising security or user experience, as existing methods either require creating a new group or manually removing members, which are time-consuming and pose security risks due to server involvement in message processing.
Innovation Solution
Implementing a method that allows users to selectively encrypt messages within an existing group chat by using ephemeral keys, where specific members are excluded from receiving the message while others receive the encrypted content, and excluded members receive a system message instead, maintaining end-to-end encryption and user privacy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If end-to-end encryption is implemented in group chats, then security is improved, but the ability to selectively exclude recipients deteriorates
Solution Approach 1:
The patent segments the group chat message distribution by creating separate encrypted message streams for different recipient subsets. The system divides the group members into included and excluded subsets, and generates distinct encrypted versions of the same message for each subset, allowing selective delivery while maintaining end-to-end encryption for each segment independently.
Solution Approach 2:
The patent applies local quality by allowing different encryption properties for different recipients within the same group chat. Each recipient receives a message encrypted with their specific key pair, enabling the sender to control which recipients get which messages while maintaining uniform security standards across all communications.
2Ease of operation
If selective exclusion of recipients is implemented, then ease of operation is improved, but device complexity worsens
Solution Approach 1:
The patent implements preliminary action by pre-distributing public keys to all group members before selective message delivery is needed. The system establishes the cryptographic infrastructure in advance, so that when selective exclusion is required, the sender can simply choose which pre-configured keys to use for encryption, avoiding complex real-time key generation and management.
3Ease of operation
If manual member removal is used for exclusion, then ease of operation worsens, but security is improved
Solution Approach 1:
The patent uses copying by creating multiple encrypted versions of the same message, each copied and encrypted with a different recipient's public key. This allows the sender to distribute the message to selected recipients without altering the group composition or requiring server-side message modification, maintaining both security and operational simplicity.
Data Source
AI summary
Embodiments include receiving input of a new message for a group of members having end-to-end encryption in which first keys encrypt and second keys decrypt the new message, determining that a subset of the members in the group is excluded from receiving the new message, and selectively encrypting the new message for the members of the group by encrypting the new message by first keys corresponding to ones of the members of the group while choosing not to encrypt the new message with first keys corresponding to the subset of the members. An aspect includes transmitting the new message encrypted by the first keys to the members, and in response to choosing not to encrypt the new message with first keys corresponding to the subset, causing a system message to be transmitted to the subset excluded from receiving the new message, the system message affecting a presentation to the subset.