1. Home
  2. Wireless Networking
  3. strange Laptop to Router thruput speeds

strange Laptop to Router thruput speeds

I've got a Linksys Wireless-N home network (WRT300N router & WPC300N adapter).

My router is in the living room and the laptop is 25ft away in the bedroom. Neither unit gets moved yet internal LAN speeds vary tremendously within a matter of minutes. For example, using IPERF, I got these test results from readings taken 5 minutes apart:

[1868] local 192.168.1.101 port 1443 connected with 192.168.1.102 port 5001 [ ID] Interval Transfer Bandwidth [1868] 0.0-10.0 sec 32.1 MBytes 26.9 Mbits/sec ........................................................................................................................... [1868] local 192.168.1.101 port 2461 connected with 192.168.1.100 port 5001 [ ID] Interval Transfer Bandwidth [1868] 0.0-10.0 sec 8.98 MBytes 7.51 Mbits/sec
Reply to
umo
Loading thread data ...

"umo" hath wroth:

- What exact IPerf command line did you use?

- UDP or TCP on the server side?

- You're testing from the laptop to/from what computah? Another wireless computer or a wired desktop? (It should be a desktop).

Incidentally, I'm getting about the same thing with my WRT54GS (with DD-WRT v23 sp2) from my desktop to my laptop. My guess(tm) is that you're only connected at 54MBits/sec. Try moving the laptop close to the router and see if it improves.

However, before you start playing with the wireless part, move the laptop to near the router, turn *OFF* the wireless, and plug in directly to the router with a CAT5 ethernet cable. If you get a

100baseT-FDX connection, you should be able to do about wire speed on the IPerf benchmark or about 70Mbits/sec. If you can't do that, then something is wrong with the "other" computer.

As for variations in performance, that's reflections and interference. As the wireless connection speed goes up, the sensitivity to interference goes up along with it. Also, if you have the 802.11b compatibility mode enabled, you'll see a tremendous performance hit when even one 802.11b packet comes drifting your way.

Reply to
Jeff Liebermann

Jeff Liebermann hath wroth:

Notice the two lines from your test:

Why is the target machine .102 in the first line, and .100 in the 2nd. Why did the IP address change in 5 minutes? Why the funny port numbers? What exactly are you doing?

This is what I get using a wired PIII/1GHz with W2K as a server and a wireless HP Ze2000 laptop for the client with a 54Mbit/sec connection to a WRT54GS with DD-WRT v23 SP2.

Reply to
Jeff Liebermann

Jeff Liebermann hath wroth:

Well, 70Mbits/sec might be a bit pessimistic. I'm getting 94Mbits/sec with a direct 100baseTX-FDX ethernet connection:

Reply to
Jeff Liebermann

Server side: iperf -s

Client side: iperf -c 192.168.1.102...1st test Client side: iperf -c 192.168.1.100...2nd test

Wireless connection speed 161Mbs.

Test is from laptop to TCP wired desktop.

Latop within a foot of router results in 40Mbs thruput.

Wired connection is 100Mbs.

Router was rebooted before 2nd test resulting in assignment of a different IP address.

802.11b compatibility mode is enabled. Turning it off results in very slow speeds. Not sure why since I have Linksys wireless-N notebook adapter and Linksys wireless-N router.
Reply to
umo

"umo" hath wroth:

So .101 is the laptop. Which is the wired desktop? Do you have TWO desktops?

TomsNetworking got about 75 Mbits/sec thruput on a simulator with the WRT-300N:

Which is the desktop. .100 or .102 ? Do you have two desktops?

Did you measure the direct connect speed? See my results I just posted.

Muddle? The router is suppose to have a fixed IP address and assign IP's to the clients. What has a different IP address? I can't tell from your statement.

Sorry to be a pest, but I'm lost with 3 IP addresses and no clue what address belongs to what device. You also seem to have one extra device.

That's all wrong. Turning off 802.11b compatibility should improve the speed, not reduce it. No clue why, but my guess is that you have some kind of setup, config, or wiring problem.

Reply to
Jeff Liebermann

Router ip address is static...192.168.1.1

Laptop ip address remained the same....192.168.1.101

I have two desktops. Only one desktop with IPERF installed. I disconnected the 2nd desktop just before rebooting the router. This is why the ip of desktop, running server mode IPERF, was changed from .102 to .100

(Before reboot of router) desktop ip...192.168.1.102 (After reboot of router) desktop ip...192.168.1.100

Both these commands were issued from wireless laptop(.101) to desktop (iperf -c 192.168.1.102)...1st test...26.9 Mbits/sec (iperf -c 192.168.1.100)...2nd test...7.51 Mbits/sec

wired laptop connection thruput...90Mbs

I might need to tweak Network mode, CTS Protection mode and Channel settings in my Router Configuration. Currently 5 other wireless networks are within broadcast range of my router. It looks like a lot of my neighbors are into wireless networking.

Reply to
umo

"umo" hath wroth:

The way I read this is your wireless laptop gets 27Mbits/sec to 102 desktop and 7.5 to 100 desktop. The obvious deduction would be that something is broken in the WIRED connection to 102 desktop. Possibly a broken cable or NWAY mismatch. Have you tried the speed between the two desktops? My guess(tm) is that the 100 desktop is stuck in

10baseT-HDX mode, which yields about 7Mbits/sec thruput. Check the 100 computer network card settings and diagnostics.

Laptop to which desktop? Try it to both desktops. I think you'll be suprised. (Please work on being more specific.)

Those will help if you have interference, but I don't think that's the problem.

The surest sign of success is pollution. Wi-Fi is successful.

Reply to
Jeff Liebermann

Jeff Liebermann hath wroth:

Argh. That should read: The obvious deduction would be that something is broken in the WIRED connection to 100 desktop. ^^^

Reply to
Jeff Liebermann

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.