Re: To compare hostap-client mode and adhoc's mode on Atheros cards.

On Fri, 30 Sep 2005 01:21:09 +0200
Daniel Dvorak <dandee_at_hellteam.net> wrote:

> 
> Hello all,
> 
> who use wireless stuff of FreeBSD and others. :)
> 
> Have you tested and compared the infrastructure mode and the adhoc
> mode anybody ?
> 
> We have 2 servers with 681 m distance. Wireless signal is about avg.
> RSSI 20-22 on both site.
> 
> We use on one site hostap and on the second site client, of course.
> Rate is a sample rate.
> 
> The maximum bandwidth is about 1,2 MB/s in one direction.
Strange, you should get about 2MB/s on such a short distance.
 
> Problem:
> 
> If we switch cards to adhoc mode on both site the speed is 10 times
> slower. Nothing else has changed.
Do you bridge them with your wired nics or route when in adhoc mode?
How do you meassure the traffic? What is the size of the packets you're
sending.
What is the tcp windows size?
What are the values of dev.ath.0.acktimeout ?
Is net.inet.tcp.sack.enable set to 1 ?
Is there any additional latency,  eg. longer ping times on the system? 
Are you using 11a or g and what channels ?

> Has anybody come accross with it in the past or nowadays ?
I can remember having any problems running on NetBSD with both atheros
nics in adhoc bridged with wired nics. It crashed with small packets but
the throughput was "normal" as long as things were working.

Cheers,
Marcin.