Metadata and Privacy Limitations

End-to-end encryption protects content, but it does not automatically hide all metadata.

Potential metadata

• connection timing;
• IP address;
• device information;
• message size;
• relay selection;
• sender and recipient delivery patterns;
• group membership changes;
• payment settlement activity.

Minimization research directions

Null should minimize metadata through:

• reduced logging;
• short retention;
• batched message delivery;
• optional proxy or privacy-network compatibility;
• sealed-sender research;
• relay separation;
• private notification payloads;
• local contact discovery;
• transparent telemetry settings.