The SimpleX Messaging Protocol (SMP) routing scheme resembles onion routing.
Several interesting developments have recently appeared in the list of secure messengers. Among them are the first distributed group P2P chat Quiet and the first messenger without the use of user IDs SimpleX.
SimpleX. How to deliver messages without recipient ID
At first glance, it seems that communication between objects is impossible if the identifiers (IDs) of these objects are unknown. This is the reason why absolutely all existing messengers, including the most secure and protected Signal, Matrix, Session, Briar, Jami, Cwtch and others, really use user IDs in one form or another, at least randomly generated timestamps like Session ID.
Everyone has to put up with them, although the danger is obvious. Even if you use the most secure tools via Tor v3, the ID still allows you to correlate the identity of an anonymous user with profiles in social networks and determine his real name with all the ensuing consequences - selling information to data brokers and profiling by advertisers. The new SimpleX messenger is declared as the first in which user IDs are completely absent from the architecture, and in the "Inconito" mode, a new name is shown for each interlocutor.
How can messages be delivered to the recipient without an identifier? According to the technical documentation, SimpleX uses "temporary anonymous paired message queue identifiers" for this purpose, separate for each connection:
User profiles, contact lists, and groups are stored only on client devices, and messages are sent over channels with two-layer end-to-end encryption.
Quiet — encrypted P2P group chat
Unlike the SimpleX messenger, the new Quiet development positions itself as a private P2P alternative to Slack and Discord, built on Tor and IPFS ( CRDT ). So far, only the first version has been released, the service remains an experimental project, but it can already be used in practice.
The difference from Element is that Quiet does not use any servers: neither central nor its own (at the client). All data is synchronized directly between devices via Tor, and no server is required. Each "community" in Quiet has its own isolated network, so data from one community never gets to the devices of users in other communities, even in encrypted form.
The project is written in TypeScript, with Electron and React Native frontends. The peer-to-peer DBMS OrbitDB (Git + Gossip + BitTorrent) is responsible for synchronizing messages.
Access rights are managed through a standard public key infrastructure (PKI.js), where each community owner acts as a certification center for their community.
Nowadays, protecting communications is of great importance. It is not only about avoiding surveillance and wiretapping, but also about protecting privacy from the messenger itself. It is no secret that now almost all programs, applications and websites try to collect personal data about users in order to resell it to information brokers. For free applications, this is one of the main sources of income.
Privacy in messengers is especially important, because we trust these applications with the most confidential information.
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