Re: 802.11g is 54mbps, is that my bandwidth?



On Fri, 04 Nov 2005 06:16:15 -0800, LurfysMa <invalid@xxxxxxxxxxxxxxx>
wrote:

>How would I do a bandwidth test? I am about to set up a wireless
>network and would love to be able to do some testing.

Online speed testers aren't going to measure your wireless bandwidth
because the typical DSL or cable modem connections are much slower
than what the wireless is capeable of doing. To test your *WIRELESS*
speed (without being impacted by anything else) requires two
computers. One is plugged directly into the wireless router with an
ethernet cable. It should be running 100baseTX-FDX and be a fairly
high horsepower machine. The other computer is your wireless test
computer. Firewalls on both computers should be disabled to prevent
them from becoming a connectivity problem.

On each machine, run IPerf:
http://dast.nlanr.net/Projects/Iperf/
for your favorite operating systems. Setup the wired computer as a
server. Run the client version on the wireless computer. With a
54Mbit/sec connection, you should see 15-24Mbits/sec thruput maximum.
If you're getting about 15Mbits/sec, then turn *OFF* the 802.11b
compatibility feature in the unspecified model Belkin router and try
again. There are other settings that can screw up thruput.

This may also be of interest...

This is stolen from an Atheros PDF at:
http://www.atheros.com/pt/atheros_range_whitepaper.pdf
with some additions and corrections by me.

Non-overlapping Modulation Max Max Max
Channels ------- | Link TCP UDP
| | | | |
802.11b 3 CCK 11 5.9 7.1
802.11g (with
802.11b) 3 OFDM/CCK 54 14.4 19.5
802.11g only 3 OFDM 54 24.4 30.5
802.11g turbo 1 OFDM 108 42.9 54.8
802.11a 13 OFDM 54 24.4 30.5
802.11a turbo 6 OFDM 108 42.9 54.8

The paper claims that encryption is enabled for these calculations,
but my numbers seem to indicate that these number are for encryption
disabled. Dunno for sure. The Max TCP and Max UDP are the
theoretical maximum thruput rates.

--
Jeff Liebermann jeffl@xxxxxxxxxxxxxxxxxxxxxx
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
.