[MLB-WIRELESS] 1.2 MBytes/S on 10k link (was New Node to be)

[Ratbaggy]

Hi Paul,

No mistake there!  Speed is chiefly thanks to the distance control utility 
which adjusts the Ack timing.  Dan Flett found the utility a few of months 
ago and for us it has been the HOLY GRAIL as far as getting serious speed 
out of our links!!!!!!!!!

Just rechecked the settings and the radio is running at an 802.11g rate of 
24 Mbits/S.  Once the timing is sorted out the RF performance of the link to 
achieve the higher rates becomes a lot more important as energy per bit is 
lower.  Over 8.6 Km with 24 dB grids at each end and good line of sight you 
should have no trouble equalling or bettering the 1.2 MByte/S mark.

The latest (1.2.5) version of Freifunk  (and OpenWRT RC5) have the distance 
control utility built in.

We have 2 links running at decent speed now.

1) Templestowe Lower to Kangaroo Ground - 10 KM

24 dB Gridpack each end
Throughput 1.2 MBytes/S
Radios: Sparklan WX6800 (= Linksys WAP54G = WRT54G minus Switch)
Settings:-
Firmware: OpenWRT-Freifunk Ver. 1.1.4 (You should be able to achieve similar 
results with OpenWRT)
dctrl 16000
24 MBPS radio rate
Wireless Mode: Ad Hoc
CTS protection disable
Frame Burst enable
Radio Mode = G Mode Performance (Whatever that means!)
Frag Thresh 2346
RTS Thresh 2346

2) Kangaroo Ground to Blackburn North - 15 KM

19 dB panel to 24 dB Gridpack
Throughput 1.1 MBytes/S
Radios: WRT54G
Settings:-
As above except
dctrl 22000
18 MBPS radio rate

IMPORTANTLY the units are set up to route IP NOT bridge Ethernet.  i.e. The 
bridge is disabled between wireless and Ethernet and the interfaces have 
separate IP addresses in different subnets.  Using bridging we got only 35 
KBytes/S with the other parameters identical.  There is a big problem with 
the bridging.  Peter Buncle had similar results.

We also have a number of the standard Freifunk init scripts disabled, 
firewall crond dnsmasq olsrd rdate olsr-prio.

With the two hops above strung together we get 900 KBytes/S.

A third hop which is only 3 KM uses Standard Edimax radios in bridge mode 
with a Vagi and a dodgy Galaxy antenna and runs at 600 KBytes/S.  All 3 Hops 
strung together run at 500 KBytes/S limited by the worst hop and the fact 
that the antennas are less than half a metre apart.

Please let us know how you get on!!!!!!

Regards,

David Nuttall.

----- Original Message ----- 
From: "Paul James" <paul.james at jamestronics.com>
To: "Ratbaggy" <wireless at smithsgully.net>; <melbwireless at wireless.org.au>
Sent: Thursday, May 18, 2006 6:14 PM
Subject: RE: [MLB-WIRELESS] New Node to be


> Hi,
>
> Are you really getting 1.2M BYTES/s = 9.6M BITS/s or did you mean to say
> 1.2 M bits/s?
>
> I have a number of links running with the WRT54GS and get about 2M
> bits/s over an 8.6km link using 24dBi Grids at each end.
>
> If you are getting 1.2M Bytes over 10Km I would love to know more
> details.
>
> Regards,
>
> Paul