[Xastir-dev] Xastir Igate question

[Curt, WE7U]

On Wed, 21 Oct 2009, John Ronan wrote:

> We've changed all our Digipeaters to a 7 second dupe timer.  To test this, I 
> was sending some messages the other night from an internet connected host, 
> but they didn't appear on RF like I was expecting (after 8 seconds), then I 
> had a thought,  I wonder if the Xastir i-gate in wexford was taking priority 
> as it could have heard the station 'last' on RF (I need to re-read how the 
> APRS-IS works to be sure).

Xastir and other igates usually keep track of which stations they've
heard on local RF within the last hour.  If a message or ACK/REJ
packet comes along for a station that has been heard recently, and
if the global and particular-interface igate switches have been set
properly, Xastir will then dump that packet out on RF.

Xastir also has some logic in there for whether that another igate
beat it to the punch/already transmitted the packet to RF.  In that
case Xastir plays nice and doesn't transmit it.

There's also logic for seeing if the station is a ham station or a
non-authenticated internet station that originated the packet.  If
ham, it'll send it to RF, otherwise no.

Then there's other logic for dupe-checking and for loop-checking.
See src/igate.c for all of the details, ask more questions if you
get lost.

-- 
Curt, WE7U.                         <http://www.eskimo.com/~archer>
    APRS:  Where it's at!                    <http://www.xastir.org>
   Lotto:  A tax on people who are bad at math. - unknown
Windows:  Microsoft's tax on computer illiterates. - WE7U.
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