[aprssig] station capability flags
jdw at eng.uah.edu
Wed Feb 28 17:21:07 CST 2007
There was some discussion in the past few days about not knowing
which stations were acting as Igates. One thing that has always
seemed missing in the APRS protocol is a way to indicate station
attributes. Selecting an icon is quite restrictive. What if it's a
digi with a weather station, or emergency power, or an Igate, or all
of the above? How you you indicate more than one, without doing
network traffic analysis?
In the absence of a dedicated field added to the protocol, it seems
to me we could get a very limited set of flags by using the TOCALL
SSID bits. A quick scan of my tnc log file didn't show any TOCALL
addresses using an SSID other than 0.
One approach would be using the 4 bits to flag the 4 most useful
attributes that may not be indicated by the station's icon.
Another method, more complex, would be to define 15 common sets of
attributes indicated by the non-zero SSID.
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