[aprssig] APRS Digipeter Design Questions

Curt, WE7U archer at eskimo.com
Fri Apr 29 11:15:07 EDT 2005


On Fri, 29 Apr 2005, Jason Winningham wrote:

> > 3C.  What parts of a packet should I include in the CRC calculation?
>
> Well, I guess it's conceivable that 2 stations could have exactly the
> same payload (2 mobile stations, especially if they're close and/or
> running position ambiguity?), so maybe originating callsign + payload??

Due to Mic-E protocol you also need to include the DEST callsign
field, as that is part of your location.  That means you need
SRC/DEST/INFO.

You should be able to ignore all the digi's, right?  Different paths
for the same payload would be considered the same for dupe-checking
purposes.

--
Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
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