[aprssig] Premptive Digipeating (b) PATH MARKING

[Steve Dimse]

On Nov 30, 2012, at 12:35 PM, Robert Bruninga wrote:

> Taking comments to date, I added the sentence about keeping the remainder
> of the path open, and attempted to address Steve Dimse's very valid points
> about traceability.  I'm suggesting we can use the RR bits in the SSID
> field. CAN WE DO THIS?

I think this is a very bad idea. You are depending on every AX-25 programmer to have followed the spec exactly and not taken any shortcuts. If your experience with the APRS spec taught you anything it should have taught you that programmers love to make assumptions and take shortcuts - especially when dealing with microcontrollers and their limited memory.

> INDICATORS:  …
>  If dropped, then the packet
> arrives with only the preemptive digipeater's MYCALL and remaing path as
> normally done.  All prior path data is lost. 

I do not think you should remove prior used digis, so if your premptive digi sees

K4HG>APRS,WIDE*,WIDE,WIDE,WB4APR,GATE:. . . 

if should send

K4HG>APRS,WIDE,WB4APR*,GATE:. . . 

Steve K4HG