On Tue, 2008-09-02 at 11:20 +0900, Nguyen Lan wrote:
> Bernd Petrovitsch wrote:
> > Routing tables of two hosts may be inconsistent at any time. But that is
> > not a unique "feature" of OLSR but IMHO of (almost?) all IP-routing
> > protocols (including the "old ones"  from the cable world like RIP and
> > OSPF).
> > In the wireless world, it is just more visible because the latency and
> > packet loss are (much) larger than on Gbit cables.
> >   
> Exactly. I see strange things in routing table when OLSR working with 
> lossy links so I just thought that it could be good if there is a 
> solution to prevent TCs from losses.

TC losses are not the only problem. And to detect and recover lost
packets, one needs at least an
- explicit "ACK" in the protocol (implying that the sender knows all
  it's intended recipients) and 
- the bandwidth (and CPU power) for these "ACK"s and
- a timeout (how many seconds?) for the "send an acked TC" action.

Since TC messages are simply rebroadcasted anyways after a few seconds,
one saves the above.

So one has to live with the inconsistency at least during the timeout if
no "ACK" comes back.
And that didn't even solve the problem but is at most part of the
solution. So the inconsistency won't vanish anyways.

So what do we would actually gain with ACKed TCs?

	Bernd
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