My wifi at home is completely random, sometimes it will work fine, and other times it will cut off every five minutes. I'll be watching a video online and the internet will just stop, but still says i'm connected. Sometimes it stops for a minute and comes back, but usually I have to turn wifi off/on. Really annoying when I'm doing homework or something online and I click the link to the next question or to submit something and it says no internet connection. I've tried every possible fix, including switching to G only, and nothing works.
The wifi at school sometimes works fine, but other times it times out after 30 seconds. Setting up a continuous ping solved this, but doesn't work at home.
Both wifi networks work absolutely perfectly when using Windows ON THE SAME MACHINE. This is just a joke, and I don't know how Apple hasn't fixed this yet. It's clearly a Lion glitch or bug, it just shows how much apple cares (or doesn't care) about their computers these days.
If what you say is true, that older routers are not able to handle the requirements of 802.11n, than I would think that my fairly new and firmware updated Apple Airport Extreme would not have problems with my new iMac that came with Lion installed. But it does. And I don't think that having to go to a slower means of connecting is the way I should have to go with an all Apple system.
When you click on the wireless tab in the airport utility, and the click the Wireless Options... button at the bottom, what does the Radio Mode selection show?
Note that Lion update 10.7.2 (http://support.apple.com/kb/HT4767) mentions this:
"Address an issue that may cause a delay in accessing the network after waking from sleep."
And Lion update 10.7.3 (http://support.apple.com/kb/HT5048) mentions this:
"Resolve a Wi-Fi connection issue when waking from sleep"
So just in case you are not already updated, you should probably do so. The evidence that a continuous ping works to keep the wifi network up (at school, not home) makes me wonder whether the two updates above have been applied yet, since they both are involved with power/sleep issues.
Lastly, the fact that this wifi+sleep issue has been mentioned in two successive OSX updates is somewhat unsettling. Personally, I never saw any wifi+sleep issues, but then my system was already updated to 10.7.3.
I show this:
My problem is that when I wake from sleep, sometimes I'm connected and sometimes I'm not. When I go to the dropdown menu showing the various connections available, my channel is always there, but it doesn't seem to be able to find it. When I click on it, it then connects. Prior to the last iMac WiFi update, I was dropping the signal frequently, and that problem seems to have gone away.
I haven't tried setting it for 802.11 b/g only. My laptop running Snow Leopard and my DVD player which connects to stream movies, have no problems connecting.
Sorry I don't know the correct terminology and I'm not in front of my machine. It's a window you can access from settings that presents, basically, a huge dump of a whole bunch of general hardware info, but it also has a list of network interfaces where you can see, e.g. IP, connected mode, speed, etc. I tried to look it up a few minutes ago (figuring that my post might be incomprehensible) but I didn't find it. There may even be a better place to see what mode your wifi is connected at, but I am not familiar enough with Mac to know those details yet. Perhaps if you open a terminal and typed "ifconfig" ? I can't recall whether that shows the connected mode though. I don't think so.
I just noticed that when my iMac 27'' drops the WiFi network and I click on the WiFi icon in the system bar: NO networks are shown at all, i.e. not the neighbours etc.
that surely means it's not a problem with my router, but the Mac losing WiFi connectivity completely, no matter if it's my router or the neighbours.
I assume the problem to be with the iMac network card or iMac software, NOT the router
You are completely correct. However, as a stop-gap measure to attain at least some measure of usable connectivity until the root cause is finally solved, consider that it might be possible to change a setting on the router in order to accommodate the Mac for the time being. This has not worked for everyone, and I don't claim that it should, but it has worked for me.
In my personal case (I can't speak for what is going on with anyone else's machine) I reckon either:
a) The wifi driver in Lion is buggy w.r.t. mode N (this is likely, because it has apparently been patched at least twice in the last two updates, and besides, the only device I have wifi trouble with is iMac, everything else, 6 other wifi devices show no problems whatsoever)
b) My router's support for mode N is buggy (this is possible, because it's a cheap router and cheaper routers are famous for not enjoying using multiple modes simultaneoulsy)
c) The power management (sleep) software in Lion is buggy (seems unlikely that all the bugginess would be concentrated only in the wifi device and not elsewhere in the power management system, and also, I never saw problems with wifi-after-sleep myself [10.7.3]. I would lose internet access simply while browsing the net, between, say, every 2-40 mins; as I said: intermittent)
d) There is a strange electrical interference that causes problems only with my Mac(s), and disappears when I use mode G instead of mode N, even though both were using 2.4 GHz (I find this extremely unlikely).
In case anyone missed my first post, I received *two* iMacs that both had this wifi problem of intermittently losing the connection (even though the network icon indicated full strength connection at the time), both could temporarily regain wifi traffic by turning wifi off and on, and both were ultimately fixed by my router-mode-change from N to G. Twice is very unlikely to be coincidental. Other people have tried this change and observed no improvement,but again, I find it highly unlikely that I will be the only one on this forum to have *this* specific problem.
The immense irony, of course, is that I got a Mac so that I wouldn't have to deal with stuff like this any more . Anyway, so far so good, the wifi thing has been my only problem so far. I have poured *man-months* into Linux troubleshooting, kernel recompilation and random driver troubleshooting before.
Thanks, I found them. They are:
PHY Mode: 802.11n
Country Code: US
Network Type: Infrastructure
Security: WPA2 Personal
Signal / Noise: -51 dBm / -97 dBm
Transmit Rate: 243
Channel 149 is "n" only, and channel 1 I believe is either "g or b". The first line "PHY Mode shows "n" so I think I can assume that that's how I'm connected.