[aprssig] Question about 'H-bit' handling and WIDEn-N paths

[James Washer]

Great thanks... I had "assumed" people were just keeping the tranmitted CRC, which of course, wouldn't work here.

thanks

 - jim
On Fri, 28 Jan 2005 10:46:52 -0600
"AE5PL Lists" <HamLists at ametx.com> wrote:

> Good question.  Dupe check for APRS should be based on callsign-SSID,
> unproto (no SSID), and the I-field.  The via path should be ignored as
> this changes with digipeating (as you noted).  The SSID on the unproto
> is ignored because this could be changed SSID routing.  The unproto
> should be part of the CRC because it is used as data in APRS (Mic-E, for
> example).
> 
> 73,
> 
> Pete Loveall AE5PL 
> 
> > -----Original Message-----
> > From: James Washer
> > Posted At: Friday, January 28, 2005 10:19 AM
> > Subject: Re: [aprssig] Question about 'H-bit' handling and 
> > WIDEn-N paths
> > 
> > Ok.. you bring up another interesting question. You say that 
> > by keeping a history of 30seconds worth of CRC's we can avoid 
> > sending dupes, but setting the H-bit OR decrementing 
> > WIDEn-N/TRACEn-N will change the CRC. So what are they doing? 
> > Calculating a special CRC on the payload or something?
> 
> _______________________________________________
> aprssig mailing list
> aprssig at lists.tapr.org
> https://lists.tapr.org/cgi-bin/mailman/listinfo/aprssig
>