[aprssig] Q: Fine point on Paths

Robert Bruninga bruninga at usna.edu
Tue Aug 19 16:53:28 EDT 2008

The WIDEn-N algorithm only looks at the ending "N" and only
decrements it on each hop until it gets to zero.  THen it sets
the has-been-digipeated bit so the path will stop.  That is all
there is to the technical process.  Other than also ignoring
everyother permutation and combination of the path for that same
packet (hence the perfect dupe suppression that was missing in
prior systems using WIDE, RELAY, TRACE, SS and soforth.

> The...(not highly recommended) path WIDE1-1,WIDE2-2
> Should actually be  WIDE1-1,WIDE3-2   [change "2" > "3"]
> So that the world knows you initially specified a 3 hop.
> Is this a valid observation, or do I still need 
> to change my smokes?

True, in a perfect fully traceable N-network then a path of
WIDE1-1,WIDE3-2 would arrive as DIGI1,WIDE1,DIGI2,DIGI3,WIDE3*
showing a 3 hop path...   BUT, because it will be forever before
all digis are converted from non-traceable "N" digis to fully
traceable New-N "S" digis, then the path that arrives as
DIGI1,WIDE1,DIGI2,DIGI3,WIDE3* could just as easily be someone
using W1-1,W3-3 which is actually FOUR hops.

Personally, I would never want to appear to be using one more
hop then I am actually using.

Thus I use WIDE1-1,WIDE2-1 and assume every one can add the two
digi fields together and know I am using only 2 hops.


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