Problem with dual band airport extreme speed...

[spiritlevel]

I have been having a long term problem with my dual band airport extreme...

The good news - the 5 Ghz band works great - I get very consistent download speeds of around 12.5 Mbps on my MacBook Pro.

The bad news, its not the same story with the other band. The speed is somewhat inconsistent and generally very slow - usually around 1-2 Mbps on my Macbook pro (although I did do one speedtest that got 8Mbps - def the exception though). On my iPhone 3g and my new iPhone 4, I am yet to get a speed greater than 1Mbps (and its been as low as 220 Kbps) its always slower than the 1.5 Mbps I get over 3g!

Can anyone tell me what the problem might be and how I might go about troubleshooting/fixing it? unfortunately I'm a bit clueless about networking...

thanks

 

[MacLovin78]

Well, I would think it is likely being caused by interference on the a/b/g channel which I believe runs on the 2.4GHz frequency. Your iPhone 4 will not connect to your N network as you have it running 5 GHz. The iPhone 4 can only connect to N on the 2.4 GHz spectrum.

So I would download AirRadar and check out the channels of the surrounding networks. Chances are there are a bunch of networks around you that are all on the same channel that are causing interference. Find out which channel has not been used or pick the channel where the lowest signal strength and least amount of channels is being used and go with that one. See if that helps your performance. Other than that you could possibly have a defective unit.

 

[spiritlevel]

That was it! - Thank you so much

Air Radar showed that 3 other networks near me were using the same 2.4 Ghz channel. Changed that and now I am getting a little over 11 Mbps on the laptop and a little over 8 Mbps on the phone - so problem solved!

Thanks again.

 

[JediMeister]

Just for future reference, installing AirRadar or KisMAC or other network sniffer applications is wholly unnecessary if you have 10.6. You can see detailed information about nearby local networks by opening System Profiler and selecting AirPort in the Network category on the left. You can see the router's BSSID, the channel, the type of security, etc. This will, of course, still not show any closed networks.

 

[macleod199]

Well, I would think it is likely being caused by interference on the a/b/g channel which I believe runs on the 2.4GHz frequency. Your iPhone 4 will not connect to your N network as you have it running 5 GHz. The iPhone 4 can only connect to N on the 2.4 GHz spectrum.

So I would download AirRadar and check out the channels of the surrounding networks. Chances are there are a bunch of networks around you that are all on the same channel that are causing interference. Find out which channel has not been used or pick the channel where the lowest signal strength and least amount of channels is being used and go with that one. See if that helps your performance. Other than that you could possibly have a defective unit.

Small quibble - 'a' is the original 5 GHz standard. 'g' brought 'a'-like speeds to 2.4 GHz.