[aprssig] Help with q-Constructs

[John Gorkos]

I'm working on the javAPRSlib parsers again, and I need a little help
understanding the Q-constructs as injected by the APRS servers.
Here's a sample beacon:
*N0NPO-1 <http://aprs.fi/?c=raw&limit=&call=N0NPO-1>*
>APOT21,WIDE1-1,WIDE2-2,qAS,KC0WIF-1<http://aprs.fi/?c=raw&limit=&call=KC0WIF-1>
:!4422.30N/10023.30W>235/008/A=000593 13.7V  76F

So, this device is set to beacon to WIDE1-1, WIDE2-2.  According to Pete's
q-Construct page:
*qAS* - Packet was received from another server or generated by this
server. The latter case would be for a beacon generated by the server. Due
to the virtual nature of APRS-IS, use of beacon packets by servers is
strongly discouraged. The callSSID following the qAS is the login or IP
address of the first identifiable server (see algorithm).
(http://www.aprs-is.net/q.aspx)
I don't believe this is the "latter case", so what exactly has happened
here?  Is this as simple as the IGATE KC0WIF-1 picking this packet up
directly on the air and sending on to APRS-IS?  If that's the case, why
isn't the qAR construct used?  is there a simple explanation of the
difference, that I can put in my "APRS for Dummies and Naval Academy
Graduates" notebook?

Thanks.
John Gorkos
AB0OO
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