[Olsr-users] Link Quality Fields

[Bhat, Ishwara]

Thanks a lot.

Please tell if there is any reason for fixing etx_ff's window to 16 second. 

Can't this be configurable? 

For instance when we use OLSR for control applications involving mobile sensors, such field would be very useful. Different sensor networks have different field topology & scenarios, response time etc.
In such applications flexibility with link decision greatly helps.


And with etc_fpm, what is the purpose of averaging from infinite Hellos ? I thought this helps only if mobility is low. But applications where each node is highly mobile, then considering say 2 minute old hellos would not be appropriate..?


Thanks,
Ishwar

-----Original Message-----
From: (spam-protected) [mailto:(spam-protected)] On Behalf Of Henning Rogge
Sent: Tuesday, February 03, 2009 1:59 PM
To: (spam-protected)
Subject: Re: [Olsr-users] Link Quality Fields

Am Tuesday 03 February 2009 08:25:05 schrieb Bhat, Ishwara:
> For OLSR's LQ, how many Hello packets are considered for link quality
> calculation ?
Depends on the LQ algorithm you use.

etx_float and etx_fpm use an exponential moving average, so they consider an 
"infinite amount of hellos".
etx_ff considers all OLSR packages (not only hellos) within the last 16 
seconds.

> In windows build of OLSRd  (0.5.5) I saw that 'LinkQualityWinSize' is a
> configuration parameter regarding this. In linux 0.5.6-r2, I did not
> find anything similar.
Yes, window size is gone... it's no longer usable because we changed the LQ 
algorithm.

> However I found - LinkQualityAging in linux olsrd.conf.  How exactly is
> this used ?
LQaging is the aging parameter of the exp. moving average for etx_fpm and 
etx_float.

(the next version of OLSR will move all LQ algorithms into real plugins, so 
each of them can have parameters of it's own).

etx_ff does not have any parameters.

> Is there any other field which influence LQ/NLQ and ETX ?
There is the "lq multiplier" parameter, but most times you should keep it on 
"1".

Henning

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