[aprssig] WIDE1-1,WIDE2-2 vs WIDE3-3

Ron Stordahl ron.stordahl at digikey.com
Tue Jan 10 12:39:02 EST 2006

For the sake of this example, this discussion is for a N=3 area, i.e. 
where a maximum of 3 digipeats are permitted.  Also my experience is 
with UIDIGI-ROM's primarily, so I will confine my discussion to them.

In such an area I  believe the recommended maximum via would be:

via WIDE1-1,WIDE2-2 rather than via WIDE3-3

This would be the case since WIDE1-1 is included to as to take advantage 
of any 'fill-in' digis which limit their response to just WIDE1-1.  
Additionally if this transmission is heard by a UIDIGI-ROM, it will 
repeat it and send it on with the remaining unused via of WIDE2-2.  
Subsequent UIDIGI-ROM's will repeat this, the first leaving a remaining 
via of WIDE2-1, the second repeating it without any additional repeats 
possible.  Thus the limit of 3 is enforced.

Instead if the initial route was WIDE3-3, no properly configured 
'fill-in' digi will repeat the packet, however the UIDIGI-ROM's will act 
properly enforcing the N=3 limit.

However if the user sends:

via WIDE1-1,WIDE3-3, he will obtain 4 digipeats in either the case of 
it's being initially repeated by a fill-in digi or by UIDIGI-ROM, thus 
the limit of 3 has been broken.

If I were concerned enough about this in my N=3 area, I would configure 
my UIDIGI-ROM as N=2 limited digi's, and then WIDE1-1,WIDE2-2 would 
obtain 3 repeats and WIDE1-1,WIDE3-3 would be limited to just 2, as 
WIDE3-3 would be in the UID list as a literal.

It is possible I suppose that some smarter digipeaters would restrict 
WIDE1-1,WIDE3-3 to a total of 3.  Are there such 'smarter' digipeaters?

Ron Stordahl, N5IN

More information about the aprssig mailing list