[aprssig] are write-only APRS-IS clients valid? (dynamic Map?)

[Robert Bruninga]

If I had the skills, what I would like to see is a map of the USA of all
digipeaters with their PHG circles shaded yellow.  Then all such PHG
circles that enclose a 2-way IGate to be shaded green, and all PHG circles
that do not have a 2-way, but do have a 1-way Igate to be shaded red.

Then everyone could see how the network is "working".  To me, the lack of
2-way Igates in range of most digis is the #1 problem in APRS.

Now I think the answer is that the APRS-IS does not have any exclusive
mechanism to know what is a 2-way and what is a one-way.  If this is still
true, we must come up with a system to fix that.

A brute force method might be to have some 2-way CZAR algorithm in the
middle of the night, originate "messages" to each digipeater in the
country.  If said Czar then sees the packet heard-on-RF then he can mark
that digi's area (or nearby IGate) as being two way.

Of course the digi is not "message capable" so it does not send an ACK,
but the APRS-IS should be able to see if the local IGate sent the message
to RF.?

Any better ideas to dynamically know where the APRS-IS messaging is
working and where it is broke?

Remember, "messageing" is the most powerful fundamental of APRS in that it
provides the only point-to-point mechanism in APRS.  Do not equate it with
just saying "hi".  It allows any application to exchange data across the
APRS system and all of these potential applications are BROKE until we
improve the 2-way to RF system.

Bob, Wb4APR