Why Privacy Matters in Messaging
Source: Dev.to
Most modern messaging apps prioritize ease of use, often at the expense of privacy. Many services track not only the content of your messages but also metadata such as who you talk to, when you send messages, and how frequently you communicate. This metadata can reveal a great deal about a person’s life and relationships, even without reading the actual messages. Therefore, privacy should be built into the system design from the outset, not treated as an afterthought.
Encrypting Messages
In the EchoId project, messages are encrypted before they leave the device.
- AES is used as a symmetric encryption algorithm, meaning the same key encrypts and decrypts the data.
- RSA encrypts the AES key itself.
Hybrid Encryption Process
- Generate a random AES key.
- Encrypt the message with the AES key.
- Encrypt the AES key with the recipient’s RSA public key.
- Send the encrypted AES key and the encrypted message together.
This approach, often called hybrid encryption, combines the speed of AES for bulk data encryption with the secure key exchange capabilities of RSA.
Purpose of the Design
- AES provides fast encryption of the message payload.
- RSA safely distributes the AES key to the intended recipient.
Together, they keep messages encrypted while maintaining efficient transmission.
What This Means
In simple terms, the message you send is transformed into unreadable data before it leaves your device. Only the intended receiver, who can decrypt the RSA‑encrypted AES key, can revert that data back to the original message. This ensures that even if the network or server is compromised, the message content remains unreadable.
Final Note
I am currently experimenting with this approach while building EchoId, a privacy‑focused messaging system that also explores encrypted communication and WebRTC‑based calls.