[aprssig] Standard Decay of old objects?

Robert Bruninga bruninga at usna.edu
Wed Jul 23 09:39:48 EDT 2008

K9DCI pointed out a problem with Objects.

With our renewed emphasis on placing objects on APRS to serve as
local information for such things as hamfests, meetings, etc,
there is the problem of what to do about old objects.
Fortunately if the object is transmitted from an APRS client
software, then it can be killed when it is no longer applicable.
This eliminates the object from all systems and data bases.

But we have also shown how objects can be posted by D7 and
D700's that do not have a kill function.  That plus, a lot of
objects are never killed...

Which brings up the point that we need a standard "OLD AGE"
definition for objects.

I like the way FINDU.COM decays out a callsign if it has not
been heard in 10 days.  That seems appropriate.  But since APRS
is a real-time system, an object that is active is by definition
being transmited at least once every 30 minutes while it is
valid (the standard APRS net cycle time).  And after 80 minutes,
(by APRS standard) any thing not heard is considered

I wonder if we should establish a standard AGE limit on objects
that will auto-erase-disappear..  My guess would be 3 days?
That allows for Monday Afternoon review of weekend events, but
then clears the map so that an old HFEST object does not remain
on the map forever...  (but it also shows the advantage of the
new format HFEST-ddx that includes the date so you can tell when
you missed it)...


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