[Xastir] What does "local" mean?

[BobDonnell at arkalmus.com]

Another consideration is that you need to set this flag at the time that
the packet in question is parsed, and to not clear the flag if a
digipeat of a packet sourced by that station is later heard.  The flag
should only be cleared when the station's record is deleted, or in the
event a 'clear local' menu item is implemented.  No - that's NOT a
feature request - at least not from ME!

Parsing the digipeater field for WIDEx-y where x=y also depends on the
originating station playing "by the rules" by setting x=y in their
unproto path.  There's nothing in most TNC firmware (any?) that enforces
that entry.  So a station could set their path to be via WIDE2-7 and
it'd be within the protocol, but would spoof Xastir into believing that
stations that are 5 hops out are local.  Curt:  I'd expect Bill, WA7NWP
to try this later this afternoon...

73, Bob, KD7NM

>-----Original Message-----
>From: xastir-bounces at xastir.org [mailto:xastir-bounces at xastir.org]On
>Behalf Of Curt Mills, WE7U
>Sent: Friday, January 10, 2003 10:09 AM
>To: Jack Twilley
>Cc: Juergen Frank; Reuven Z Gevaryahu; Xastir Users
>Subject: Re: [Xastir] What does "local" mean?
>
>
>On Fri, 10 Jan 2003, Jack Twilley wrote:
>
>> Doesn't the asterisk indicate the station which performed the
>> transmission?  The station in question is a digipeater six miles away
>> so I expected it to show up as a local station.
>
>Nope.  Unfortunately, with the advent of these generic APRS calls,
>you have to dig further.  When you have something like:
>
>
>    WE7U*>APRS,WIDE3-3,WIDE:Something
>
>
>It means it came from WE7U.  When you have this instead:
>
>
>    WE7U*>APRS,WIDE3-2,WIDE:Something
>
>
>It means that one of the wide-area digipeaters sent it out (the
>first digipeater in the path in this case).  There's no asterisk in
>this case on the last station that sent it.  Makes it a bit harder
>to determine who's local and who's not.
>
>I believe when that field decrements all the way and the next one
>takes over, the "digipeated" bit will get set, so it would appear
>like this:
>
>
>    WE7U*>APRS,WIDE3-1*,WIDE:Something
>
>or like this:
>
>    WE7U>APRS,WIDE3-1*,WIDE:Something
>
>
>Depending on which type of TNC is receive it (some put an asterisk
>for every "digipeated" bit that is set, some put one only on the
>last one).
>
>When I looked at this a few weeks ago, I decided that I'd need to
>add another flag to the record to indicate whether the station was
>heard locally (as opposed to heard via TNC).  I think I might have
>added that to the record, but haven't added the extra parsing yet to
>set that value or to do something with it on display.  As you can
>see, it's not quite trivial.
>
>-- 
>Curt Mills, WE7U                    hacker_NO_SPAM_ at tc.fluke.com
>Senior Methods Engineer/SysAdmin
>"Lotto:    A tax on people who are bad at math!"
>"Windows:  Microsoft's tax on computer illiterates!" -- WE7U
>"The world DOES revolve around me:  I picked the coordinate system!"
>
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