Mesh Networking Basics

Learning Objectives

1. Explain what LoRa and mesh networking are in plain terms
2. Power on and navigate a T-Deck device
3. Send and receive text messages on LA-Mesh
4. Understand channels, PSKs, and basic encryption concepts
5. Read the node list and interpret signal quality (SNR/RSSI)

Part 1: What Is a Mesh Network? (30 min)

Every device is a relay. If one node goes down, the network re-routes around it. No cell towers, no internet needed.

Analogy: A bucket brigade -- each person passes the bucket to the next. If one person steps away, the chain re-routes.

Part 2: What Is LoRa? (20 min)

Part 3: Your First Message (45 min)

1. Power on: Hold power button for 3 seconds
2. Home screen: Identify node list, channel indicator, battery level
3. Send a message: Navigate to message screen, type, press Send
4. Check node list: How many nodes? What does SNR mean?

Exercise: Pair up. Walk to opposite sides of the building. Send messages. Note SNR degradation with distance.

Part 4: Mesh Routing (20 min)

You ──(hop 1)──→ Router A ──(hop 2)──→ Router B ──(hop 3)──→ Friend

meshtastic --traceroute '!<node-id>'

Part 5: Channels and Encryption (20 min)

• Default PSK (AQ==) is publicly known -- NEVER used on LA-Mesh
• LA-Mesh uses custom 32-byte PSK distributed in-person only
• Direct messages use additional PKC (Public Key Cryptography)

Resources

• Meshtastic documentation
• Meshtastic Site Planner
• LA-Mesh onboarding guide