[aprssig] NE Illinois Balloon Tracks

[Rick Green]

On Fri, 24 Jul 2009, Robert Bruninga wrote:

>>> I believe that a digi should be filtered
>>> so that it will digi only packets which
>>> originated within its defined 'service area',
>>> no matter what path was requested.
>
> Rather absurd for most digipeaters.  In the footprint of most
> that I see that would limit APRS to about 1 or 2 home stations
> and an occasional mobile.  Reducing the map display from a
> hundred or so down to a half dozen would surely bore even the
> most avid shack-potato and kill APRS..
>
   The 'service area' is not the coverage footprint of the digi.  It's the 
area that the local LAN can support.  It might be one hop in some places, 
and five in others.  I can imagine situations where you might define a 
service area just a few miles in one direction, but hundreds in another. 
How about a digi on the east slope of the mountains just outside LA?  You 
wouldn't want the service area to include ANY of the basin to the west, 
but you'd have to go many hundreds of miles to the east to get enough 
packets to keep your digi busy...


  > But you are absolutely right about some high density 
places... > And those are ALREADY configured that way.  They are
> enforced-one-hop areas where there are more than a hundred or so
> in each footprint..  The LA basin, and a few others.
>
> See http://aprs.org/fixingLA.html
>
> Simply configure any digi to enforce one-hop only, and you get
> much less channel loading, yet can support thte large number of
> users in the footprint.
>
   I'm looking for better specification ability than hop count.  With 
mountains, valleys, interstate corridors, etc. and geographic filtering, 
we could have a more self-managing network, and no need for the user to 
learn all the 'special' paths unique to the geography they're travelling 
thru.

   I'd like something along the lines of the 'Tim Newport-Peace Special-use 
Airspace' format for a geographical filter specification language.

-- 
Rick Green

"Those who would give up essential Liberty, to purchase a little
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                                -President Barack Obama 20 Jan 2009