[Olsr-dev] OLSRd 0.5.4 and 0.5.5 with ETT available

[Erik Tromp]

The problem with the reported rate is that in reality the throughput is
usually a lot lower.

As an example: my WLAN connection currently reports a rate of 130 Mbit/sec .
However, the highest transfer rate I have seen is approx. 6 MByte/sec (48
Mbit/sec). Somehow there is some overhead. Is that a fixed factor (130/48 =
2,7 ?) Or is that factor dependent on other things?

This is what I meant by "it is difficult to determine the "quality" based on
only these [L1/L2]metrics."

But, even if the reported rate is not the actual rate, at least it is better
than nothing. That is, provided the WLAN interface has the ability to choose
for itself its bit rate. If a node owner chooses to fix the rate to say
54Mbit/s, then the OLSR network will think there is a very good quality link
there, while in fact there may be not.

Erik



> -----Oorspronkelijk bericht-----
> Van: (spam-protected) 
> [mailto:(spam-protected)] Namens Henning Rogge
> Verzonden: donderdag 13 november 2008 16:56
> Aan: (spam-protected)
> Onderwerp: Re: [Olsr-dev] OLSRd 0.5.4 and 0.5.5 with ETT available
> 
> On Thursday 13 November 2008 16:18:03 John Hay wrote:
> >  > ifconfig wlan0 list sta
> >
> > ADDR               AID CHAN RATE RSSI IDLE  TXSEQ  RXSEQ CAPS FLAG
> > 00:15:6d:53:1f:ee    0   64   6M 6.0    0   3271  42432 I    A
> > 00:02:6f:41:19:2b    0   64   6M 13.5    0  53104  39744 I    A
> > 00:80:48:50:9a:48    0   64   6M 8.0    0     82     96 I    A
> > 00:02:6f:41:19:2b    0   64  36M 15.0   30   7664  22896 I    A
> > 00:02:6f:41:19:2b    0   64  36M 15.5   30   8135  36928 I    A
> > 00:02:6f:41:19:2b    0   64  48M 15.0    0   8640  39712 I    A
> > 00:15:6d:53:20:0b    0   64   6M 2.5    0      0  16208 I    A
> > ##############################
> 
> Sounds good, have to look at the ifconfig sourcecode in BSD... :)
> 
> So now we need a good linux sollution (someone with 
> experience in nl80211 here
> ?) and windows of course...
> 
> Henning
>