Why This Matters
Signal is reportedly moving toward letting people register without a phone number, using zero-knowledge proofs — the same cryptographic technique it already applies to donation badges, backup payments, and private group membership. That would remove one of the most-cited privacy objections to Signal, since a phone number is a strong real-world identifier. The discussion also highlights Signal's core design claim: the client is built not to trust the server, so privacy shouldn't hinge on server behavior.
Key Takeaways
- Signal plans phone-number-free registration built on zero-knowledge proofs.
- The same ZK tech already underpins donation badges, backup payments, and groups, so the server can't link users to specific donations or groups.
- Because the Signal client is designed not to trust the server, concerns about subpoenaed server-side metadata are meant to be structurally limited.
you have legitimate concerns, but you’re very wrong about this. zero-knowledge proofs are not only the technology behind donation badges and backup payments, but also behind groups. they can’t tie you to a specific donation just like they can’t tie you to a specific group.
kevino: kevino: Not to forget, signal could always be subpeaned to keep metadata information relating to certain accounts.
the great thing about Signal is the client is designed to already not trust the server. in fact you can show that Signal is perfectly safe without even looking at server code.
GoKawiil