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Offline & Mesh

Offline Messaging

Cipher works even without internet. Communicate via Bluetooth, WiFi Direct, and LoRa radio when traditional connectivity isn't available.

Why Offline Matters

In many situations, internet connectivity is unavailable or unreliable:

  • Natural disasters that take down cell towers and infrastructure
  • Remote areas without cellular coverage
  • Crowded events where networks are overwhelmed
  • Censorship scenarios where internet is blocked or monitored
  • Underground/indoor locations with no signal

Cipher's mesh networking ensures you can always communicate with nearby users, and messages automatically route through available peers to reach their destination.

Available Transport Methods

Bluetooth Low Energy (BLE)

Range: ~100 metersSpeed: ~1 MbpsPower: Very Low

Ideal for device-to-device communication. Always-on background scanning automatically discovers nearby Cipher users.

WiFi Direct

Range: ~200 metersSpeed: ~250 MbpsPower: Medium

High-bandwidth local networking without a router. Perfect for sharing files and media with nearby contacts.

LoRa Radio

Range: ~15 kmSpeed: ~50 kbpsPower: Low

Long-range, low-bandwidth communication. Requires compatible hardware (Meshtastic devices). Great for emergencies.

How Mesh Routing Works

When you send a message without internet, Cipher automatically:

  1. Scans for nearby devices using BLE and WiFi Direct
  2. Encrypts the message with your recipient's public key
  3. Broadcasts to nearby peers who can relay it
  4. Each peer stores and forwards the message toward the destination
  5. The message hops through the network until it reaches someone with internet or the recipient directly
You ──BLE──> Peer A ──WiFi──> Peer B ──Internet──> Recipient
                 │
                 └──LoRa──> Peer C (backup route)

Privacy in Mesh Mode

Even in mesh mode, your privacy is protected:

  • End-to-end encryption: Relay nodes cannot read your messages
  • Onion routing: Optional multi-hop encryption hides the destination
  • Randomized identifiers: Your device rotates BLE addresses to prevent tracking
  • Cover traffic: Dummy messages make traffic analysis harder

Automatic Fallback

Cipher automatically switches between transport methods based on availability:

  1. Internet available: Use P2P network via internet
  2. Internet unavailable, WiFi Direct possible: Use WiFi Direct
  3. Limited connectivity: Use Bluetooth mesh
  4. No direct path: Store message for later delivery

Messages are stored encrypted on your device and automatically delivered when a path becomes available. You don't need to do anything—it just works.

Hardware Requirements

📱

BLE

Any modern smartphone

📶

WiFi Direct

Most smartphones

📻

LoRa

External device (Meshtastic)

Getting Started

Offline messaging is enabled by default. To optimize your experience:

  1. Go to Settings → Offline Mode
  2. Enable the transport methods you want to use
  3. For LoRa, pair your Meshtastic device
  4. Grant Bluetooth and location permissions when prompted

That's it! Cipher will automatically use offline transports when needed.

Security ArchitectureBluetooth Mode