Features

Zentalk is built from the ground up for privacy, security, and decentralization.

End-to-End Encryption

• X3DH + Double Ratchet - Signal Protocol for key exchange and message encryption
• All messages encrypted on device - Keys never leave your device
• Forward secrecy - Past messages stay secure even if keys are compromised

Post-Quantum Security

• Hybrid X25519 + Kyber-768 - Classical and post-quantum cryptography combined
• NIST FIPS 203 compliant - Following standardized post-quantum algorithms
• Future-proof against quantum computers - Protected from future quantum attacks

Decentralized Network

• No central servers - No single point of failure or control
• Peer-to-peer mesh network - Direct connections between users
• DHT for peer discovery - Distributed hash table for finding peers

Privacy Features

• Zero knowledge - No data collection, no metadata storage
• 3-hop relay routing - Zentalk’s own relay system for anonymity (not Tor)
• Stealth addresses - One-time addresses to prevent tracking
• Traffic padding - Constant traffic to prevent timing analysis

Messaging

• Text, images, files, voice messages - Full multimedia support
• Group chats with Sender Keys - Efficient encryption for groups
• Disappearing messages - Auto-delete after 1h, 24h, 7d, or 30d
• Link previews - Privacy-first previews without leaking your IP

Calls

• Voice & video calls - WebRTC-based real-time communication
• E2EE signaling - Encrypted call setup and negotiation
• Group calls - Support for up to 6 participants
• Screen sharing - Share your screen securely

Key Backup

• Encrypted export - Backup keys in .zbak format
• PBKDF2 + AES-256-GCM - Strong key derivation and encryption
• Cross-device restore - Restore your identity on a new device

Permanent Backup

• Mesh storage backup - DMs, groups, and channels backed up to decentralized network
• No expiration - Permanent storage with wallet-derived encryption
• Auto-backup on delete - Backups update automatically when you delete content
• Multi-chunk architecture - Separate chunks for DMs (v1.0), Groups (v2.0), Channels (v2.0)
• Erasure coding - 10+5 shards survive up to 5 node failures

Invite Friends

• Personalized links - Share zentalk.chat/u/yourname
• QR codes - Generate and download QR codes for in-person sharing
• Multi-platform sharing - WhatsApp, Telegram, X/Twitter, SMS, Email
• Native share sheet - Mobile device share integration
• Mesh-based tracking - Privacy-preserving invite statistics
• Deep link flow - Recipients start chatting immediately after wallet connection

Channels

• Broadcast channels - One-to-many encrypted messaging
• Subscriber management - Admin controls for channel members
• Message history sync - New subscribers receive history
• Same E2EE guarantees - Full encryption like regular messages