[aprssig] WIDE1-1,WIDE2-2 vs WIDE3-3
ron.stordahl at digikey.com
Tue Jan 10 11:39:02 CST 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
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