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MESH Planning

Created Thursday 26 December 2019

The Goal

Build a wireless mesh network that will be:

  • useful for everyday Ham user needs,
  • available for use in emergencies,
  • able to connect to other networks if desired,
  • able to accomodate any number of users.

The net topology problem:

The limited range of the wireless routers available at practical prices makes it difficult to create a mesh that covers an extended area. Our approach is to encourage Hams to set up mesh nets in their local areas, and then offer some means of connecting them together over a larger geographical area.

The question is, what hardware and software should be used to connect them?

Required characteristics

  • Bandwidth sufficient to run common Web-based applications.
  • Minimal latency. One of the problems of mesh networks is that latency can increase as the net increases in size.
  • Isolation from the Internet. Mesh nets operating under Part 97 need to be protected from intrusion from outside.
  • Maximal coverage of our area. At microwave frequencies, solid objects block signals from a node, creating shadow areas that cannot contact it.

Other desirable characteristics

  • Allow end-user nodes to be added and removed automatically.
  • Remote management of routers.
  • Minimize interference by using Part 97 channels whenever possible.
  • Mature technology that won't need frequent updating or replacement.

Limiting factors

  • VPNs (tunnels) are encrypted, so cannot be used under Part 97.
  • Connecting node location: area coverage requires that connecting nodes be placed at an elevation sufficient to provide line-of-sight connection to local nets.

Possible approaches

Quick list

Connecting linking methods: 1 AREDN mesh nodes 2 New Packet Radio (NPR) 3 Link over the public HamWAN network. 4 Our own extended LAN/WAN to which only our local mesh nets can connect:

  • Using Part 15 channels
  • Using HamWAN specs and channels: Part 97


1. AREDN mesh nodes


  • Integral part of the mesh — no bridging needed


  • Large mesh net can be slow

2. New Packet Radio (NPR)


  • Greatest range


  • Limited bandwidth
  • Immature technology — not ready for VOIP, etc.
  • Limited number of nodes can connect (currently 7)
  • Requires special hardware, is the most expensive


  • Takes advantage of existing infrastructure


  • No encryption allowed, so VPN not possible
  • Could expose mesh nets to the Internet

4. Our own extended LAN/WAN

  • Essentially a private network to which only our local mesh nets can connect.
  • Could use HamWAN setup of Mikrotik routers, with our choice of channel.


  • Completely under our control
  • Configuration details available from HamWAN


  • Requires bridging hardware
  • Needs frequent administration
Using Part 15 channels


  • Can use VPNs to connect local mesh nets


  • Channels can be busy
Using Part 97 channels

Use VLANs to route traffic between meshes?


  • Work the same as the Internet, but can use Part 97 channels.


  • Requires active management.
lun/mesh_net_planning.txt · Last modified: 2019/12/30 19:47 by KC7MM