[aprssig] Msg reply path

Lynn W. Deffenbaugh (Mr) ldeffenb at homeside.to
Fri Oct 4 06:23:44 EDT 2013


I've considered that on numerous occasions but the issue is that in too 
many networks there are too many different styles of digipeaters.

In a perfect world, every digipeater would insert its callsign and 
decrement the N in WIDEn-N or XXn-N so that assumptions could be made at 
the receiver as to what the path originally was.

Unfortunately, the APRS RF network is anything but perfect.  There are 
digipeaters that don't insert their callsign.  There are digipeaters 
that replace an alias with their callsign (WIDE1-1 is a popular one to 
disappear).  There are digipeaters that don't decrement, but mark things 
used (ever seen a WIDE1-1*?).  And there are digipeaters that simply 
repeat the packet as received with no changes.

So, until all of the above are completely gone from the network and the 
entire planet is fully WIDEn-N compliant (which means replacing a bunch 
of obsolete hardware that cannot be made fully compliant), I for one am 
not going to release software whose default settings don't work in some 
areas.  The support aspects are overwhelming.

Besides, just because you received a message that says AB7-3 doesn't 
mean you need to transmit an entire AB7-7 path.  In actual fact an AB7-4 
or AB7-5 might be sufficient.  Only a human can know for sure (or at 
least make a better guess).

And the logical extension to this is to simply reverse the used portion 
of the path asking the response message to go back out through the 
digipeaters that delivered it.  That also doesn't work because it's not 
necessarily true that if A can hear B on the way here then B can hear A 
on the way back.  Reversing used digipeaters explicitly is, IMHO, less 
likely to succeed than using a beefed-up alias.

Now, if you were to ask software authors to make the received path of 
message packets visible to the user and provide a QSO-specific 
manually-entered outbound message path override (which of course, 
defaults to the station's normal beacon path), that might be a step in 
the right direction.

Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and Win32

On 10/3/2013 9:58 PM, Tony VE6MVP wrote:
> At 07:38 AM 2013-10-02, Andrew P. wrote:
>
> >So we can find each other when needed, here's the start of a list of
> >APRS software authors.
>
> Excellent idea!  I'm thinking.  Wow, what an influential group is 
> following this mailing list.  Now what suggestions do I have that are 
> generic? <smile>
>
> Here's one.    If your device/software can reply to messages please do 
> not use the device/software default path.  If you can review the path 
> of the message you have received and attempt to use that path when 
> replying.
>
> Scenario.  My device/software is set to beacon on WIDE2-2.  But I get 
> a message via AB7-7 (Alberta).  I'd like to have the acknowledgement 
> and my reply automatically set to use AB7-7.  Of course by the time I 
> get the message it might be AB7-3 but you get the idea.
>
> Tony  VA6OO
>
>
> _______________________________________________
> aprssig mailing list
> aprssig at tapr.org
> http://www.tapr.org/mailman/listinfo/aprssig

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.tapr.org/pipermail/aprssig_lists.tapr.org/attachments/20131004/8fda995b/attachment.html>


More information about the aprssig mailing list