Dependency removed: Carrier networks, internet connectivity, and centralized messaging platforms - you can communicate when infrastructure fails.
When cellular networks go down, internet is unavailable, or service providers shut down, most people lose all ability to coordinate with others. This section covers the communications stack that works when everything else fails - from LAN messaging to radio to mesh networks.
When you have a LAN but no internet:
- LAN communication - messaging and coordination within your local network; Matrix homeserver; Mattermost; Mumble for voice
- Peer-to-peer messaging - direct device-to-device communication without a server; Briar, Jami
- Local forums and bulletin boards - community information sharing on a local network; Lemmy, Discourse
- Store-and-forward message drops - asynchronous message exchange for intermittent connectivity
When no network infrastructure exists:
- Amateur radio - licensed operation; voice and digital modes; repeater networks; EmComm (emergency communications)
- Digital radio modes - Winlink (email over radio), JS8Call (keyboard-to-keyboard messaging), VARA (high-speed HF)
- Low-bandwidth data links - transmitting critical data (GPS coordinates, status) over narrow-band links
- Scheduled check-ins - timed communication windows for coordinating distributed teams
- Meshtastic - LoRa mesh networking; no infrastructure required; GPS sharing; text messaging over kilometers
- AREDN - amateur radio emergency data network; broadband mesh over licensed frequencies
- Delay-tolerant networking - asynchronous message passing for disconnected environments
- Satellite communications - Iridium, Starlink; costs, offline modes, and appropriate use cases
- Sneakernet and removable media - physical transport of digital information when no radio path exists
- Content distribution via local hotspots - serving information to nearby devices over Wi-Fi without internet
- Community Mesh Network - Meshtastic nodes covering a neighborhood
- Emergency Communications Kit - portable radio + digital modes kit for go-bag use
- Neighborhood Information Network - local-only LAN with forum and file sharing
| Failure |
Result |
Mitigation |
| Internet down |
Cloud messaging fails |
Self-hosted Matrix on LAN |
| Cellular down |
SMS/calls fail |
Meshtastic, radio |
| LAN down |
Local messaging fails |
Direct radio / physical handoff |
| Radio jamming |
Digital links fail |
Multiple frequency bands |