Sporadic high latency on 5ghz network

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Sporadic high latency on 5ghz network

I am having random increases in latency on my 5 GHz network. My current setup is: cable modem connected to an airport extreme, a time capsule and airport express connected via wifi (acting as access points and extends of 802.11g network). The speed/latency of the b/g network is excellent and appears to have no issues. However, the 5 ghz N network has random surges in latency from 25 ms to 250 ms or worse. There is no known interference (microwaves or cordless phones). Is there something that I can do to help fix the issue?

Mac OS X (10.6.2)

Posted on Jun 29, 2012 11:24 AM

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Answer 1

Philly_Phan

Level 7

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Jun 29, 2012 1:13 PM in response to kwjoh

I had noticeable performance problems when using a 5G channel. I went back to 2.4G and, despite the fact that all my neighbors use those channels, it's far and away better than 5G.

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Answer 2

kwjoh Author

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Jun 30, 2012 12:26 AM in response to kwjoh

Thanks for the help, I was getting the impression that 5 GHz was essentially the issue with performance. I switched over and have had now issues. Is this an apple issue or an 802.11n issue? Thanks again!

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Answer 3

Philly_Phan

Level 7

20,737 points

Jun 30, 2012 4:55 AM in response to kwjoh

You're most welcome. I have no clue if it's Apple or 802.11n.

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Answer 4

lunieri

Level 2

284 points

Jun 30, 2012 5:34 AM in response to kwjoh

All wifi networks are susceptible to interference and broadband noise. Just because there are no cordless phones or microwaves operating that you are aware of, doesn't mean you don't have an interference problem.

I would suggest that you get a network sniffing application and monitor the network activity in your area for a few minutes. The sniffer will tell you what networks are around and what channels they are using. You can then use that information to manually configure your airport network to use a 5ghz or 2.4 ghz channel that is not being used at all, or one that has the lowest number of competitors. remember, that while the 5ghz band supports greater throughput, it also has a shorter transmission range.

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Answer 5

Philly_Phan

Level 7

20,737 points

Jun 30, 2012 6:28 AM in response to lunieri

lunieri wrote:

I would suggest that you get a network sniffing application and monitor the network activity in your area for a few minutes. The sniffer will tell you what networks are around and what channels they are using. You can then use that information to manually configure your airport network to use a 5ghz or 2.4 ghz channel that is not being used at all, or one that has the lowest number of competitors. remember, that while the 5ghz band supports greater throughput, it also has a shorter transmission range.

Been there, done that. That's precisely the reason why I tried the 5G channels. I also used the sniffer to manually choose a 2.4G channel. Results totally illogical in both cases (extremely poor performance). Obtained best performance by choosing the crowded 2.4G channels AND putting the channel selection in "Auto."

Transmission range should not be a factor. I did my testing with my iMac, which is six feet from the Express.

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Answer 6

lunieri

Level 2

284 points

Jun 30, 2012 10:59 AM in response to Philly_Phan

Well unfortunately the network sniffer doesn't show you ALL the noise on the frequency just the networks that are transmitting.

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