Re: Specific Paths for RFOnly


James Ewen
 

Dan,

Like Rob said, if your buddy can hear the third digi, don’t put more path elements in the outbound path. You have a specific station you are aiming to contact, so there is no need to flood an area with your packets where there is no need to do so. 

As stated, if you put specific names digipeaters in your outbound path, then those digipeaters will need to be configured to respond to those requests via the defined path element. Most probably will respond, unless the operator has a non-compliant setting. 

Not only that, but each digipeater will need to be able to copy the full packet with no degradation from collisions or other sources of interference or signal loss. 

Putting NOGATE or RFONLY in the path will stop i-gates that honour those settings from pushing the packet to the APRS-IS stream. 

IF the destination station is able to copy your packet successfully and all stations are compliant, then your buddy will have heard the packet via a completely RF path. 

Your buddy can look at the packet he received and observe the path elements used in the packet to confirm the digipeaters that handled the packet. Again, this is only true if the digipeaters that handled the packet are set up properly. 

Naming the digipeaters to be used was the standard way of using the packet radio network before Bob came up with the idea of using generic aliases that are used to make APRS magic happen. Congratulations on rediscovering packet radio! 😀

Seriously, it’s kind of fun to see someone wondering if this new way to use packet radio will work or not, which in fact was the defacto “only” way packet radio worked in the original incantation. 

So now we come to the question “Why?”  Why are you wanting to use an RFONLY path? Just to see if it can be done? As an experiment to see if you can communicate in an emergency if the internet goes away? Other? 

All of the above are great reasons to test your RF network, and as always amateur radio should be about experimenting and learning. I encourage everyone to try this on their local RF network. You can learn a lot about your local network in this way. 

If your network is interesting enough, you might be able to send a packet on a round trip back to yourself. Pick a path that takes the packet away, and then loops back towards your station via string of digis. You only need to be able to hear the packet at the end of its trip. You can observe the path it took by looking at the used digipeaters list in the raw packet. 

There’s a lot of good information in the raw packets that tells you about the health of your network. 

But if your local network is broken by poor digipeater configurations, overloaded by too many packets, poor user configurations, or otherwise, you may have a tough time making this work. 

Most times when I look into raw packets in an area when looking for a root cause of an issue, I find a poor digipeater network, overloaded digipeaters, misconfigured digipeaters, and more. 

It is rare to find a well planned and implemented digipeater network that isn’t overloaded by poorly configured user traffic. 

Good luck with your experiments. Make sure your buddy tries the same experiments from his end as well!



On Fri, Jan 7, 2022 at 07:19 Dan Hurd <dan@...> wrote:
Should I have NOGATE in my path to insure it doesn't get gated at the first DIGI ? (These are big wide area digi's that all igate also) 

Dan W5DMH

--
James
VE6SRV

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