[aprssig] Premptive Digipeating
bruninga at usna.edu
Fri Nov 30 16:37:08 CST 2012
> Naming it "preemptive" is somewhat misleading.
> It does not preempt digipeater nodes... later in the path:
We don't want to turn off the rest of the path because that would violate
the sender's intent, and would cripple some very good applications of this
> That will do WIDE3-3 repeats all over the place,
> except that the NODE2 would pick it up immediately
> even from first transmission.
True. Nothing in preemptive digipeating is meant to encourage any further
use of generic digipeating beyond 2 generic hops as is currently the
agreed practice. The W3-3 above is abusive as it has always been. The
added NODE2 on the end is not, since it is a single "targeted" dupe on the
end of a really big mess. So a big mess +1 is not the problem. The
problem is using the 3-3 big mess before it.
> Also explicit chains will do repeats all over the place:
Not really. It can make at most 3 copies, and at least 1. This is a huge
savings over even WIDE2-2 which can generate as many as from 4 to 16
copies. In fact, a 3 hop preemtive path above is even better than an
explicit 3 hop path because it always generates 3 hops, whereas the
Premptive will generate on average 1.5 hops.
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