I posted this problem on the Fedora Forum - the post was read many times but nobody came up with any ideas, so I thought it worthwhile repeating here.

I use wifi to connect to my router - using a cable is not an option at the moment.

On my Asus AMD platform I am using a "pin Avid" 802.11N usb adapter. The Network window under All Settings shows this connected at a constant 72 Mb/s, with good signal strength.

The problem is that even though the adapter always stays connected, data does not flow as expected. During the day the flow of data stops after a period ranging from about 2 minutes to 10 minutes. The only way to regain Web access is to reset the connection in the Network window. The easiest way of doing this is to click on either the lock or the wifi symbol. This is not a happy way to use the computer..

If I replace the 802.11N device with a Belkin F5D7050 adapter, which uses 802.11G, the same problem occurs, but is worsened by the fact that the Belin takes far longer to restart. In addition, the Belkin connection speed is often much lower than the supposed maximum of 54 Mb/s.

If I use the computer in the early hours, 2 or 3 a.m., the connection never drops - data flow/browsing is uninterrupted, the adapter does not need any resetting.

This then seems to be related to the number of wifi networks active in my immediate neighborhood. During the day I can see up to nine wifi networks
other than my own. In the wee hours of the morning this number drops to one or two other networks.

I have changed the wifi channel to 8, which according to Sky is lesser used than the popular non-overlapping channels 1, 6, and 11. Situation unchanged.

Then the real puzzle - on my Dell computer, which is on the same desk, the Belkin wifi adapter works fine and never needs resetting.

Is there some sort of buffer problem on the Asus AMD? If so, where?

Any ideas?
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F22 on an Asus M2N68-AM PLUS motherboard, with AMD Phenom 9600 Quad and 4 GB RAM.

F22 on Dell Inspiron 530S with 1GB RAM.

Used two devices and both exhibit same. Good test, that seems to rule out driver if they do in fact use different drivers as the chip inside may be same.

Guess you could look at maybe a few things. One is setting a static or long term lease on this linux issue.

Look at or make a log of system resources. Maybe some resource has a memory leak. Be sure to look at /var logs too for clues.

Guess it could be some power issue like acpi or apm.

Might look at setting up wireshark too, guess it could be attacked.

Thanks for your suggestions. I am not sure what setting a static or long-term lease means - please elucidate.

I have not yet had the time to scour the logs, but meanwhile I have found a way around this problem. On the Fedora Forum, in thread 303163. Fedora 21, connected to wireless network but no internet access, user dragonbite suggested a constant ping of the router in the background to prevent loss of the Internet connection when using a wireless USB dongle.

I find that pinging the router every two seconds works for me - the system maintains Internet connection - but I have no idea as to why it works.

I would say that you're in close proximity to other wireless devices running on the same channel.

You are probably correct. But does this mean that I am hogging the channel and making wifi connection more difficult for others?

I don't think that any of the other nearby wifi owners are sufficiently knowledgeable to be able to even find out what channel their routers are using. They are all probably using the default channels originally set by their ISPs - and the most popular channels are supposedly 1,6 and 11.