VashonMesh Initial Meeting

Our 1st Meeting

The local ham radio club’s message server has seen a number of posts related to mesh-networking in the last few years.

Michael Meyers, the head of Vashon-Maury Island Radio Club’s Emergency Communications (EmComm) team (aka Auxiliary Communication Service (ACS), ARES, and other names) was curious about mesh technology’s value for local disaster preparedness efforts.

He called a gathering of local mesh-networking enthusiasts to explore its use for EmComm.


Agenda & Real™ Meeting Notes

Michael arranged an initial January 22nd meeting at the library, He showed a brief Powerpoint slideshow available on the club’s file server and updated it during the meeting with notes. File access is for group members. It contains a list of the initial dozen or so attendees.

All but one participants had a ham radio sign and should have server access, but since the intent is to serve the public (including non-radio club members), a brief review of the discussion is here. (Maybe it should be put onto the Radio Club’s public website going forward?!)

Discussion

CAVEAT: This is based on my very limited knowledge!

Current mesh radios allow 255 character texting directly between radios, or to repeaters which carry the messages onward a certain number of hops. The range can be between 2km in urban environments up to 10 km in ideal, open conditions.

These radios are inexpensive, roughly $25-50. No license is required to use. Most devices can serve either as a radio or repeater - upload (‘flash’) the software for the desired purpose.

Fixed repeaters with solar backed power supplies and mounted antennas can cost ~$100 or more. Spenser suggests evaluating higher performance repeaters too.

A half-dozen repeaters might cover much of Vashon-Maury Island. Additional repeaters could extend coverage where desired & valued. Spenser is war-driving(?) around to check possible coverage and evaluating tools for evaluating coverage!

Channels

[John is confused about how easily one radio can switch between different groups of radio operators. It sounds like radios & repeaters are manually tuned to one channel (below) and don’t have scanning & other advanced capabilities. He’ll shut up until he actual has one!]

Mesh-networks use specific terminology. We (I?) need to figure that out & adopt it.

• Channels don’t need a device, they propagate via flood.
• “Rooms” are per device, which makes them single point of failure. Fault tolerant options may exist.

Vashon might start with a couple channels, then expand as we learn more:

1. #puget-sound
2. #vashon: a general Community Channel (or maybe this is a sub-channel of the above?) Future:
3. #vashon-emcomm: Emergency Communications
4. #vashon-cert
5. #vashon-mrc

Traditional Challenges with Shared Radio Channels

• Who (if anyone) acts as “net control” (i.e., coordinates who speaks when) on each channel!
• Channels can get overloaded if many (or talkative few) folks try to talk at once.
• How to separate the wheat from the chaff with lots of overlapping conversations?
• If a device is not on, the message doesn’t get delivered. Message queuing & “room servers” exist as potential solutions.

Channels can be private (via a shared key) or public. Do sub-channels exist?

• Private rooms are “invite only” but then if the key gets out I don’t think you can do anything about it. Any user can block messages from another user, but they could just change their key. Plus they can still listen.

Radios and Repeater Devices to Consider

Spenser likes:

• KEEPTEEN D5L Mesh Solar LoRa Repeater: All in one. Sounds like it’s well supported and well regarded. This is going to be my “plug and play” repeater for travel and events.

• WisBlock Meshtastic Starter Kit & RAK Wireless Solar Unify Enclosure Case: This is going to be my experimental repeater for trying out code changes.

Action Items

• Hang some test repeaters on PugetMesh
• Settle on MeshCore
• Consider future VashonMesh on separate frequency
• Consider separate EMCOMM channel on VashonMesh
• Create a Wiki on Groups.io with simple get started instructions
• Michael to set up meeting at Farcy+Library - try for Feb 12 or 19