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[aprssig] APRS Digipeter Design Questions

Curt, WE7U archer at eskimo.com
Fri Apr 29 15:15:07 UTC 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

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

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