Erratic wireless speeds with Buffalo WHR-HP-G54

[daveyfx]

Hi all.

I'm currently utilizing a Buffalo WHR-HP-G54 running DD-WRT v23 SP3 (04/30/07) mini - build 6888. I have just one wireless device on my network and have noticed that I rarely achieve anywhere near 54 Mbps wireless speeds.

After initially connecting to my wireless network, my speed will display as 54 Mbps but after doing any light transferring or surfing on the net, I'll notice that the speed will diminish to as low as 1 Mbps. However, it tends to fluctuate between 5.5 Mbps and 11 Mbps. If I allow my wireless connection to idle, I'll notice that the speed will occasionally crawl back up to either 48 Mbps or 54 Mbps.

I noticed this same behavior with v23 SP2 and have tried several beta builds of SP3 as well as v24, with no success. I even plugged in my old Linksys USB wireless network adapter to see if a difference could be spotted. No dice... in fact it seemed even worse.

I've pulled up the wireless survey in DD-WRT to ensure that I'm not utilizing the same channel as any surrounding networks and all looks well there.

Additionally, I'd also like to point out that my wireless card and router are no more than 10 feet apart, and my wireless signal always displays as "Excellent" (full bars at all times).

Any ideas?

Thanks much.

Dave

[golfnut]

How many wireless devices are connected to your router when you see the speed drop?

Wireless data rates are selected by the wireless adapter in your laptop based on what it thinks is the best data rate to maintain a good connection to the AP in the router. The AP in the router should have no control over this. It only broadcast the available data rates in its beacon.

If for example, there was interference and the adapter started to receive corrupted frames or excessive frame retries at 54 Mbps, it would attempt to re-transmit at a lower data rate and continue to drop the data rates in an effort to pass good data. How and when an adapter selects lower data rates is dependant on the vendor.

Based on your description, I would suspect that the router for whatever reason is not processing data frames properly and could be defective, there is a lot of interference in the area, or there is an 802.11b device communicating with your router.

If possible, set the router to G-mode only and see if the problem continues.

If you really want to find the source of the problem, you could download a free wireless data analyzer from here:

http://www.omnipeek.com/omnipeek_personal.php

Greg

[daveyfx]

I was able to determine the source of the problem. For those interested, the issue was with the wireless NIC drivers.

I have the Wireless-G 125 High-Speed PCI adapter from Buffalo and it shipped with driver version 3.104.64.52. Oddly enough, the adapter only connected at 54Mbps TOPS, and I made sure afterburner was enabled on client and router sides. After several minutes, it would drop to 1Mbps and sometimes hover up to 11Mbps (if I was lucky).

I loaded driver version 3.104.64.50, which is available on the Buffalo site and have been holding a rock solid 125Mbps (completely unwavering) for the last few hours.

Thanks for the suggestions, golfnut :D