Wifi Loosing Speed

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ov10fac
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Wifi Loosing Speed

Post by ov10fac » 2015/02/03 14:16:39

I am running a Dell Latitude E6400 with an Edimax WIFI USB card. When I first start up everything is fine and wifi works great at about 7sMB/S. After a few minutes it drops to 7MB/S. If I turn wifi off and back on back up to 72MB/S for a few minutes.

This is very strange behavior. At first I though some kind of interference so I put the usb wifi on a long USB cable and moved it away from the laptop, no difference in behavior. I have even changed my wifi base station thinking maybe some issues there, but the same behavior.

Its pretty much got me stumped. Ideas anyone?

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TrevorH
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Re: Wifi Loosing Speed

Post by TrevorH » 2015/02/03 16:17:18

Do you actually mean 72MB/s - as in megaBYTES? If so then that is about 603Mbps so is quicker than I would expect it to be. A more reasonable rate for a wireless connection is actually 7MB/s - or 58Mbps.
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aks
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Re: Wifi Loosing Speed

Post by aks » 2015/02/03 17:00:45

Wireless interference? Something's "colliding" with the signals so the back off mechanisms kick in?

ov10fac
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Re: Wifi Loosing Speed

Post by ov10fac » 2015/02/09 14:41:33

TrevorH wrote:Do you actually mean 72MB/s - as in megaBYTES? If so then that is about 603Mbps so is quicker than I would expect it to be. A more reasonable rate for a wireless connection is actually 7MB/s - or 58Mbps.
Actually 72 Mb/s is what is reported by the Network Settings.

ov10fac
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Re: Wifi Loosing Speed

Post by ov10fac » 2015/02/09 14:46:56

aks wrote:Wireless interference? Something's "colliding" with the signals so the back off mechanisms kick in?
My thoughts initially. So I put the usb wifi on a usb extension cable. Same problem. I know its not the router because I am running several other wifi devices (ipad, iphone) that are having no problems.

Many thanks for your rreply.

aks
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Re: Wifi Loosing Speed

Post by aks » 2015/02/09 17:23:36

Scan the wireless network (assuming your hardware can) to see what other radiation is out there. Last time I did that (years ago now, I used it to select the channels for my wireless stuff at home), I used Kismet.

aks
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Re: Wifi Loosing Speed

Post by aks » 2015/02/09 18:00:46

Thinking about this, there has to be some event that makes this happen. What happens when the speed drops? I suppose it could be like a bug in the wireless firmware, whereby power delivered to the antenna is above regulatory requirements and drops later (seems really unlikely though). Are you migrating from wireless router to another wireless router? Anything in the wireless logs of the wireless router?
And scan before and after the speed drop.

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