[Olsr-dev] getting the etx value to a destination

sebastian sauer (spam-protected)
Wed Jul 15 15:19:48 CEST 2009

Wed 15 Jul 2009 14:55, Henning Rogge wrote:
> Am Wed July 15 2009 14:42:13 schrieb sebastian sauer:
> > Mon 13 Jul 2009 17:11, Henning Rogge wrote:
> > > For olsrd tiptip (the development branch which will become the next
> > > stable one) we could implement a special "ask for linkcost value"
> > > command. ETX is a floating point value, so working with raw linkcost
> > > might be a good idea.
> >
> > what do mean with "raw linkcost"? The inverse of the ETX ?
> Internally OLSr use a 32 bit unsigned integer for storing the "cost" of a link 
> in the topology graph. In the case of ETX they are just a multiple of the ETX 
> value
ok. thanks for explaining. suggestion sounds good. 


> To determine which route/link is better/worse, it's enough to compare this 
> unsigned integers so you don't have to worry about ETX/linkcost 
> representation.
yep. ETX is just the one-normalized value of "this unsigned integer", so

in fact a nice practical improvment because one-normalized means an
interval [0;1] ... sucks with float rounding.

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