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[aprssig] Path Confusion and old TNC's

Robert Bruninga bruninga at usna.edu
Wed Aug 31 14:26:18 UTC 2005


> one of the goals [of the New-N paradigm] was a
>universal path of WIDE2-2 that would work 
>anywhere.  

BUT some people completely missinterpret what that 
means.  To some, it means everyone should use it 
everywhere,  which simply is not at all what it means!  
We now have packet police in the middle of the boonies 
hammering people with WIDE3-3 paths which really are 
not a problem in the vast areas of APRS wilderness.

What the sentence DOES mean is that someone who 
TRAVELS everywhere has assurrence that WIDE2-2
is a fundamental path that will work without-change 
everywhere he goes.  (except Knoxville and other
places that still have old TRACE (T) digis)...

FURTHER, I have no problem with a WIDE3-3 mobile
visiting our 2-2 area, and leaving it at WIDE3-3.
Reason is, that under the New-N paradigm, all of
our digis are set to trap WIDE3-3 and so his packet
will SUCCESSFULLY go 1 hop to an IGate but the
digi will trap the path and it will not go any farther.

That is the beauty of the New-N paradigm.  Existing
digis (with New-N settings) in dense areas can TRAP 
visiting or big-hop packets to 1 hop only so that they
get to an IGate, but do not saturate the rest of the
local network.  Its beautiful.  It works!  And we dont
need the packet police trying to jam 2-2 down 
everyone's throats in the vast wilderness where it
may not be needed.

>Now we are getting back to multiple paths and 
>confusion again.  (from the relayFIX document:)
>WIDE2-2                   General mobile recommendation 
>WIDE1-1,WIDE2-1     New 2 hop path safe everywhere
>WIDE1-1,WIDE2-2     New 3 hop path in remote areas

>when you try to  explain this to a totally new 
>APRS user, you can almost see their eyes glaze 
>over in confusion.  

Sorry, if they cannot understand digipeating and 
hops, then they are not yet ready to operate their
radio on APRS.  APRS is not some plug-and-play
entertainment video game for instant gratification.
It is a communication system for Amateur Radio
where one is expected to learn how to operate
his radio before transmitting...

>Do we really still need RELAY only or "WIDE1-1" 
>digi's which are causing this path confusion?  

Driving though Tennessee convinced me that we
do.  They have mountain top digis (and voice 
repeters) that cover HUNDREDS of miles.  But
when you get out on the fringes, you can 
always find valleys where you cannot hit the
big digi.  Usually, there is a closer home station
or WX station nearby that is perfectly capable
of digipeating the packet.

During my several hours driving across Tenn,
I was changing back and forth between
RELAY,WIDE and WIDE,WIDE (where they
have not done the New-N changeover yet,
and sure enough, RELAY,WIDE gave me
coverage where WIDE,WIDE did not.  And it
was because they had some WX stations
that are high up, that are not WIDE
digis, but do act as FILL-IN RELAY digis.
They act as feeder points to the BIG
SINGLE HIGH digi and so the system operates
very efficiently.  

WIthout the fill-in first-hop digis, and the 
SINGLE BIG DIGI, the only way to cover the 
same area would be to put up lots more WIDEn-N
digis to cover the area (or convert all the home
stations and WX stations to WIDEn-N digis)...
Thus multiplying the QRM for the same coverage
as there was before. 

>shouldn't a former RELAY digi just become a 
>fully functional WIDEn-n digi?  

NO, it would only make matters worse.

1) because almost ALL of the fill-in-digis are not 
    WIDEn-N capable.

2) Screwed up settings in WIDEn-N digis can 
    easliy make things worse than better.

3) Every such fill-in-digi now adds QRM to the
    network on EVERY packet it hears...

4) Since these FILL-IN digis will now all be
  transmitting their own copy of every pacekt
  on the air, this will JAM the mobiles in its
  vicinity from hearing packets from the big
  digi...
de WB4APR, Bob







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