How do you test the WLan speed?

Well, you could do it without software. Just copy a big file of known size from one machine to the other. Use a stopwatch to time the copy, and divide to get bytes/second. However, that's a bit crude, so using software is a good idea.

Try:

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copy a large file from one machine to the other and look at the speed results.

If you want a dedicated performance tool, try IPerf.

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setup a server on one machine and run the client on the other.

Reply to
Jeff Liebermann
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Hi, How do you test the band width for newly set up WLAN? I am using W2K pcs in a Peer to Peer LAN with 2 Dlink DWL-2000 APs. Do I need new software to do that? Thank you. G L

Reply to
GL

Get a program called ttcpw, on one machine say:

ttcpw -r -s (recieve, discard data)

and on the other say:

ttcpw -t -s (transmit, source data)

Where is either the IP address or the Windows NetBios name of the other computer.

Reply to
William P. N. Smith

so I look at the dumeter on the xp laptop and it says 6 mega bytes is that really 48 megabits and is that the limitation of the laptops slow hard drive

Reply to
bumtracks

Dumeter will work:

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I don't think it's the hard disk. However, I can't tell without a complete hardware description. The easiest test is to just time copying a big file from the hard disk to another part of the hard disk. Make sure it's big enough to fill up the 2-8Mbyte cache found in most hard disk. The seek time for the drive will slow things down, but hopefully not too badly. I can time a few laptops in the office if you want a comparison basis.

The DWL-2000AP+ will do 54Mbits/sec maximum connection speed. You won't get anywher near that good a thruput. The theoretical maximums are:

This is stolen from an Atheros PDF at:

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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.

In theory, your 48Mbits/sec is impossible for a 54Mbit/sec connection as 30.5 for UDP and 24.4 for TCP are the maximum speeds. Does your access point have "turbo" support to 108Mbits/sec? The UK firmware page doesn't show if this was added. The DWL-2000AP+ is not sold in the USA.

The 48Mbits/sec might also be limited by a half duplex 100baseTX connection between the laptop and the DWL-2000AP+. I can't tell from the specs if the DWL-2000AP+ is half duplex or full duplex on the ethernet port. If half duplex, you'll be stuck with about 50Mbits/sec maximum on the ethernet port. With full duplex, you might get up to wire speed at perhaps 85Mbits/sec.

There are other things that really affect performance. TCP requires acknowledgements, while UDP does not. You'll get much better thruput testing with UDP than with TCP. There are some things you can do to optimize and improve the efficiency of the TCP/IP stack.

Reply to
Jeff Liebermann

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