[aprssig] RADIO paths in APRS Servers

[Robert Bruninga]

>>> the RF and Internet networks are designed
>>> to accomplish the transport, not to 
>>> provide a traceback.
>>
>> I would say that is true for the APRS-IS 
>> only.  For the RF path, the New-N paradigm 
>> demands full RF traceability on all packets.

> but if someone sends a packet via wide1-1, 
> K4HG>APRS,WIDE1-1,WIDE2-1:....
> are you saying the W4XYZ digi inserts a callsign:
> K4HG>APRS,W4XYZ*,WIDE1,WIDE2-1:...

Good question.  Yes, but with the caveat that I mentioned:
"(Some WIDE1-1's will never be)."
And a few other cases of WIDE1-1 digipeating:

VAST MAJORITY:  Even though most mobiles use the path of
WIDE1-1,WIDE2-1 so that they can use any convenient fill-in
digis, I would guess that 98% of the time, those packets are
first picked up by a full-new-N digi.  Hence the vast majority
of these will get the call insertion and traceability:  
K4HG>APRS,W4XYZ*,WIDE1,WIDE2-1:...

A MINORITY:  All older KPC-3's and older KPC-3+ digis (a very
large number) have a bug which does not mark a WIDE1-1 hop as
being used up.  This bug was mitigated by having these digis do
callsign -substitution- (by using the UIDIGI function to
digipeat the WIDE1-1's):
K4HG>APRS,W4XYZ*,WIDE2-1:...

SMALL MINORITY:  Next, some WIDE1-1 fill-in digi's do use fully
capable TNC's and these also will do callsign insertion, or
substitution:  
K4HG>APRS,W4XYZ*,WIDE1,WIDE2-1:...

SMALL MINORITY:  Many of the old "TRACE" digis that used
PacComms ROMS have been converted over to be WIDE1-1 digis.
These do callsign -substitution- instead of -insertion-:
K4HG>APRS,W4XYZ*,WIDE2-1:...

SMALL MINORITY:  Some Areas such as LA use the UIDIGI function
to trap all PATHS to one hop.  These then will also do callsign
-substitution- instead of -insertion-:
K4HG>APRS,W4XYZ*,WIDE2-1:...

SMALL MINORITY:  And finally, home-fill-in digis that are made
from old pre-APRS TNC's will not do insertion or substitution
and these are UNTTRACEABLE on the first hop:
K4HG>APRS,WIDE1-1*,WIDE2-1:...

But I think these are the minority for the "traveler".  Now, for
the HOME station user that put up his own WIDE1-1 fill-in digi,
because his own mobile does not get in from his home area, yes,
most of his packets near home will be untraceable, but then, he
knows where he is...

Hope that helps...
Bob, WB4APR