Do default nodes rebroadcast private channels?

I have set up a private channel on Primary and a secondary channel LongFast on the default RF channel in EU868 (there is only one). Following this recommendation.

I can see the default messages on LongFast, there are several nodes in the area, and I can traceroute some of these LongFast stations via one or two hops.

I messaged primary with one fixed node (so with a different encryption key than AQ==) and observed the received tick another node set up with the same two channels/keys that I went for a walk test with.

I had expected the nodes I can see on LongFast to relay this private primary, but it doesn’t seem to be the case. Do I need to use the default key on my primary channel (named differently) or is my understanding of meshing wrong and I would have to be on LongFast Primary with key AQ== to be relayed

Are channels the other nodes don’t know just not relayed at all? Looking at the default in the docs

ALL (Default) - This setting will rebroadcast ALL messages from its primary mesh as well as other meshes with the same modem settings, including when encryption settings differ.

I would have expected the private mesh/channel to be relayed

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Yes that is correct.

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As I understand it normal ‘client’ nodes are now somewhat selective in what they reboardcast.

If they see two nodes apprently in direct contact, they wont reboardcast (because in theory not needed) - even in ALL mode, they still do select.

… only Router and Repeater nodes will actully reboardcast all.

I dont know the exact mechanism of this process, they might for example remember the setting for a while. So as they seen your nodes in direct communication recently, they not doing any forwarding (even if the locations have change such that it would be needed!)

Mainly based on comment here:

(I havent updated the simulator to include this selective reboardcast, I assumed all messages where retransmitted by all nodes)

… so for a more realistic test, need the two test nodes (with the private) channel to not be in direct contact for a protracted period, then might get retransmission by local nodes.

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For each packet they receive, while waiting for their rebroadcast delay, they will listen if anyone else has already rebroadcasted it. If so, they will cancel their rebroadcast.

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Ok, that makes sense. Thanks.

Can see how that could stall messages at ‘junctions’ in a split - need to add to simulator to test.

That would explain the behaviour I am seeing, which is that the private network is not being relayed. I had misread the system description as if the mesh relays packets without decoding so I expected the mesh to relay all packets if the RF parameters were right, but it seems there is some packet inspection.

So far I have only used two nodes, the feeling I am getting is I need to relay my own channels, initially I will try dropping an extra node or two configured with the private primary and perhaps the LongFast AQ== secondary. Which is fair enough, but good to know in advance!

I assume the confusion is that the initally meshtastic just used to rebroadcast everything - so called ‘flood routing’ - but later added the refinement to not reboardcast all (persuambly busy meshes get overwealmed)

… the docs havent caught up.

From what said above, it seems that ‘ROUTER’ devices would retransmit hyour private messages, just that CLIENT’s may not.

So if a router sees a packet from a node using the same radio settings, but a completely unknown channel (name, PSK), not having any of the default channels, will it still rebroadcast?

From what said above a ROUTER or REPEATER would (as long as it the ‘rebroadcast mode’ setting allows it!)

A more normal CLIENT (and presumably others client TRACKER), will only rebroadcast, if they havent heard some other node doing so.

Presumably on the basis that in a busy area, the ROUTER would take care of rebroadcasts, saving the others from bothering. (also saving battery for the mobile clients)
(althing in practice, I guess it could have been another client doing it)

… but in an area without router(s), normal clients can still build a ‘mesh’.

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