Intel Centrino N and Linksys Router Connection Speed Problem

[cheenachatze]

I had a long time problem with the connection speed between my Intel Centrino 6300 (and before that with Centrino 5300) and Linksys routers. I have Linksys WRT310N and WRT400N routers. When I connect to either router using the 2.4Ghz band, I would get a maximum speed of 54mbps, even if my laptop would be 3ft away from the router. When I connected my laptop to the WRT400N using the 5Mhz band, I would get much higher connection speed. All the routers and drivers were up to date.

When I tried my laptop with an Asus (RALink based) USB wireless adapter, I was able to connect at much higher speeds. I also have an Apple AirPort router (Gigabit Ethernet). When I connect the Intel Centrino adapter to the Airport, I also get much higher speed.

I searched all over the internet, and saw that many people have this problem with Intel Centrino adapters, mostly with Linksys routers, some with other brands. Nowhere could I find the solution. I came across some article on SNB that mentioned WWM support. I came across another article that mentioned Wireless encryption settings. I started to change some settings in both my routers, and at some stage I managed to get higher speed with the WRT400N, but not with the WRT310N. I finally managed to figure out all the settings, so I hope this will be helpful to others too:

Starting with the Centrino properties:

Open the Properties from the Device Manager. Click on the Advanced tab. Set the properties as follows:

802.11n Channel Width for band 2.4: Auto
802.11n Channel Width for band 5.2: Auto
802.11n Mode: Enabled
...
Ad Hoc QoS Mode: WMM Enabled
...
Fat Channel Intolerant: Disabled
Mixed Mode Protection: CTS to self Enabled
...
Transmit Power: Highest
Wireless Mode: 802.11a/b/g

Router settings:

Wireless > Basic Wireless Settings:

Network mode: Mixed
Radio band: Mixed
Wide channel: Auto
Standard channel: Auto

Wireless > Wireless security:

Wireless security: WPA2
Encryption: AES (do not choose "TKIP or AES")

Wireless > Advanced wireless settings:

CTS Protection mode: Disabled

Application and Gaming > QoS:

WMM Support: Enabled

I found a couple of problems in the firmware of the WRT310N. First, the CTS Protection Mode default is Auto. On the WRT400N the default is Disabled. Second, under WMM Support, the default was Disabled, even though the description says that the default is Enabled! Mind you, the router was hard reset several times, so this is a bug in the firmware.

The bottom line: with the WRT310N I get connection speed of 270 Mbps and with the WRT400N I get connection speed of 300 Mbps at either band.

Hope this helped!

 

[sfx2000]

WPA2 and WMM are required for 802.11n compliance... WPA2-AES if you want encryption that is (most people do...)

Good post and thanks for sharing!