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How quicprochat Compares to WhatsApp, Telegram, and Signal

Choosing a messenger is a trust decision. This page lays out what each popular messenger actually does with your messages, metadata, and keys — and where quicprochat offers stronger guarantees.


At a Glance

Feature WhatsApp Telegram Signal quicprochat
E2E encryption (1:1) Yes (Signal Protocol) Opt-in only ("Secret Chats") Yes (Signal Protocol) Yes (MLS, RFC 9420)
E2E encryption (groups) Yes (Sender Keys) No Yes (Sender Keys) Yes (MLS ratchet tree)
Post-compromise security (groups) No No No Yes
Forward secrecy (groups) Partial No Partial Full (per-epoch key deletion)
Post-quantum protection No No PQXDH (1:1 only) Hybrid KEM (X25519 + ML-KEM-768)
Server reads messages No (but see backups) Yes (cloud chats) No No
Server stores metadata Extensive Extensive Minimal Minimal
Open-source server No No No (since 2023) Yes (MIT)
Open-source client No Client only Yes Yes
Password auth Phone number (SMS) Phone number (SMS) Phone number (SMS) OPAQUE PAKE (password never sent)
Phone number required Yes Yes Yes No
Self-hostable No No Difficult Yes (single binary)
Protocol standard Proprietary adaptation MTProto (proprietary) Custom (well-audited) IETF RFC 9420
Wire format Protobuf (proprietary) TL (proprietary) Protobuf Protobuf + QUIC framing
Transport TCP/TLS (Noise) TCP/TLS (custom) TCP/TLS (Noise) QUIC + TLS 1.3
Decentralized / federable No No No Planned (federation scaffolded)

The Five Questions That Matter

1. Can the server read my messages?

Messenger Answer Details
WhatsApp Mostly no E2E encrypted by default, but cloud backups (Google Drive / iCloud) were unencrypted until late 2021. Even with E2E backup enabled, Meta retains metadata.
Telegram Yes (by default) Only "Secret Chats" are E2E encrypted — and those are 1:1 only, mobile only, opt-in. All group chats and default conversations are stored as plaintext on Telegram's servers.
Signal No E2E encrypted. Server stores almost nothing.
quicprochat No Server handles only opaque MLS ciphertext. It cannot decrypt, modify, or selectively censor messages — by design, not by policy.

2. What metadata does the server collect?

Metadata — who talks to whom, when, how often, group membership — can be as revealing as message content.

Messenger Metadata exposure
WhatsApp Collects contacts, usage frequency, group membership, IP addresses, device info, location data. Shares data with Meta for ad targeting (outside EU).
Telegram Collects phone number, contacts, IP addresses, device info. Stores all cloud-chat message content.
Signal Stores only phone number and last-connection timestamp. Uses sealed sender to hide sender identity from the server.
quicprochat Stores Ed25519 public keys and encrypted delivery queues. Supports sealed sender. No phone number, no contacts upload, no usage analytics. Server sees connection timing and message sizes (mitigated by traffic shaping).

3. What happens if the server is hacked?

Messenger Impact
WhatsApp Message content is safe (E2E), but attacker gets the full social graph: who talks to whom, group membership, phone numbers, profile photos, last-seen timestamps.
Telegram Attacker reads all cloud chat messages in plaintext, plus contacts, phone numbers, and media. Only secret-chat content is safe.
Signal Attacker gets very little — phone numbers and last-connection dates. Message content and metadata are not stored.
quicprochat Attacker gets opaque ciphertext (cannot decrypt), Ed25519 public keys, and connection timing. Cannot impersonate users (lacks private keys), cannot forge messages (lacks MLS group keys), cannot read history (forward secrecy — past epoch keys deleted).

4. Are my group chats truly private?

Group encryption is where the big differences emerge.

Property WhatsApp Telegram Signal quicprochat
Group E2E Yes (Sender Keys) No Yes (Sender Keys) Yes (MLS)
Group forward secrecy Partial (symmetric ratchet) None Partial (symmetric ratchet) Full (MLS epoch ratchet, old keys deleted)
Post-compromise security No — if a Sender Key leaks, all future messages from that sender are exposed until manual re-key N/A No — same Sender Key limitation Yes — any member issues an MLS Update, new epoch derived, attacker locked out
Member add/remove cost O(n) N/A O(n) O(log n) via ratchet tree
Max practical group size ~1024 (pairwise overhead) 200,000 (no E2E) ~1000 Thousands (log-scaling tree)
Group state consistency No formal guarantee N/A No formal guarantee MLS transcript hash — all members see identical state

What is post-compromise security and why does it matter?

Imagine an attacker steals one group member's keys. With WhatsApp or Signal, the attacker can read every future group message from that sender until keys are manually rotated. With quicprochat, any group member can issue an MLS Update that re-derives the group secret — the attacker is automatically locked out, without anyone needing to know a compromise occurred.

5. Am I protected against future quantum computers?

Quantum computers threaten today's encryption through "harvest now, decrypt later" — an adversary records encrypted traffic today and decrypts it years from now with a quantum computer.

Messenger Post-quantum status
WhatsApp No post-quantum protection.
Telegram No post-quantum protection.
Signal PQXDH for 1:1 chats (X25519 + ML-KEM-768). No PQ protection for groups (Sender Keys are classical-only).
quicprochat Hybrid KEM (X25519 + ML-KEM-768) protects message content. Both classical and PQ KEMs must be broken to compromise the shared secret. Applies to groups, not just 1:1.

What quicprochat Does Differently

No phone number required

WhatsApp, Telegram, and Signal all require a phone number. This ties your messaging identity to a real-world identifier that can be subpoenaed, SIM-swapped, or used for cross-service tracking. quicprochat uses Ed25519 cryptographic identity keys — no phone number, no email, no personal information.

Password never leaves your device

All three major messengers use SMS-based verification. quicprochat uses OPAQUE, an asymmetric password-authenticated key exchange where the server never sees your password — not during registration, not during login. The server stores only an opaque cryptographic record that cannot be used for offline attacks.

Self-hostable, single binary

You don't have to trust anyone's infrastructure. Run your own server with ./qpc-server. Your data stays on hardware you control. No cloud dependency, no terms of service, no policy changes that retroactively weaken your privacy.

Open protocol, open server, open client

WhatsApp's server is proprietary. Telegram's server is proprietary. Signal shut down its server source code in 2023. quicprochat is MIT-licensed — server, client, SDKs, protocol specification. You can audit every line.

IETF-standardized cryptography

WhatsApp and Signal use a custom (well-audited) protocol. Telegram uses MTProto, a custom protocol with a history of cryptographic weaknesses. quicprochat uses MLS (RFC 9420), an IETF standard designed by the academic cryptography community, with multiple independent implementations and formal security proofs.


Honest Trade-offs

No comparison is complete without acknowledging where quicprochat is behind:

Dimension WhatsApp / Signal / Telegram quicprochat
Maturity Billions (WhatsApp), hundreds of millions (Telegram), tens of millions (Signal) of battle-tested users Early-stage project
Mobile apps Polished native apps on iOS and Android CLI and TUI (mobile SDK foundations exist)
Network effect Your contacts are already there You'll need to invite people
Calling / video Built-in voice and video calls Not yet implemented
Stickers / stories / payments Rich consumer features Focused on core messaging security
Ease of setup Download app, enter phone number Build from source or use Docker

quicprochat is not trying to replace your casual chat app today. It's for people and organizations who need verifiable, self-hosted, post-quantum-ready group encryption — and who aren't willing to take a vendor's word for it.


Summary: Why Choose quicprochat?

  • Your server, your rules. Self-host on your own hardware. No third-party trust required.
  • Groups done right. MLS gives you forward secrecy and post-compromise security for groups — something no mainstream messenger offers.
  • No phone number. Cryptographic identity only. No SIM swap risk, no phone-number harvesting.
  • Post-quantum today. Hybrid X25519 + ML-KEM-768 protects group messages against future quantum computers — not just 1:1 chats.
  • Fully open. Server, client, SDKs, and protocol — all MIT-licensed and auditable.
  • IETF standard. Built on RFC 9420 (MLS), not proprietary cryptography.

Further Reading