Q: Lion WiFi Connection Problem

One important thing to remember about the RF characteristics of WiFi is related to wave length.  A 2.4ghz signal of 802.11b/g/n is 300/2400 meters or about 5" or .125m.  If you have something metal, this distance, or about 1/2 this distance away from your router, it will create "nice" reflections of the signal resulting in "multi-path" signals which can make "duplicate" packets much more likely, especially if there is another metal object that can create more reflections.  This is how "directional" attennas work.  A Yagi antenna has a refector, a driven element and director elements from back to front of the antenna.  The distance between the driven element and the reflector is has to be correct for the frequency you want to "direct" with the antenna.  So, make sure that you do not have metal objects near your WiFi router (like a metal computer case) which might be creating reflections that are resulting in multi-path that might be creating duplicate packets.

It might be that the new computers have better antenna systems and they are being affected by multipath in ways that other devices are not.

gphonei wrote:

 

One important thing to remember about the RF characteristics of WiFi is related to wave length.  A 2.4ghz signal of 802.11b/g/n is 300/2400 meters or about 5" or .125m.  If you have something metal, this distance, or about 1/2 this distance away from your router, it will create "nice" reflections of the signal resulting in "multi-path" signals which can make "duplicate" packets much more likely, especially if there is another metal object that can create more reflections.

Pretty good description.

And also one brick more in the wall of interferences and other disturbance is mostly the reason.

Thanks for that useful contribution.

Lupunus

There must be multiple, independent causes of the various wifi problems in Lion. Some people have had channel overlap and interference problems whereas my BSSID issue wasn't related to that.

hormelmeatcompany wrote:

 

There must be multiple, independent causes of the various wifi problems in Lion. Some people have had channel overlap and interference problems whereas my BSSID issue wasn't related to that.

In most cases it is not only a single reason, but more often some minor problems coincidences to a bigger and at least a remarkable one.

A lot of people had only some minor issues in the wireless not really to bother about as long as the former configuration tolerates them an a drop out occur only once a day or the network speed was in acceptable range.

I`m sure that all you wrote is absolutely correct.

BUT: In my case and in many other cases described in this post the following happened:

• Snow Leopard > no problems
• Lion > problems (same computer, same router in the same position with the same firmware and configuration, same neigborhood-networks, same flat/furniture)
• going back to Snow Leopard > no problems

In all these cases the only thing which changed is the OS. So as a matter of a fact there must be a higher sensitivity of Airport under Lion and I don`t think that rearranging everything beetween the router and the Mac by try&error is an acceptable workaround...

I agree with aechleviel. I simply think most  of people just doesn't write in forums, or in this one, for there are quite a lot worldwide.

As previous post says, point seams to be that Lion is much weaker holding a Wifi signal. Of course there are a lot of difficulties to make it, but figthing them is supposed to be be the goal in making a system stable, and the former OS were more stable, as we can see from all contributions.

So there certainly has been a change compared with SL which has to be reviewed - and not all particular problems of users, as you say, PJRIves.

I had more Wifi items with SL than with Leopard, but nothing really serious. With Lion it gets absurd - I have to turn on and off WIfi kind of every 20 minutes - it that really a long term solution? And after a while it doesn't work at all, I go to the cable and the other computer with SL (which is stable) looses signal!

Tried all mentioned on this forums on my lap and on the router, like password, chanels, ssid, my preferences and both sides of network settings, dns, ip, ping (well, that worked but it is absurd to have to run something in parallel - thats not the idea, ist it?), and so on. My lap and home details are just a drop in a river of cases. So, I hope there will be a measure soon, it is a shame it takes so long to "unbug" such a basical need. Are we getting to the Microsoft buggy releases? Is like saying : "ok, until our next fix your spacebar wont work".

Don't know if this has been mentioned here: ivp6

Look at http://forums.macrumors.com/showthread.php?t=119, DJRiful suggests a bug with automatic ivp6 and a fix. Makes sense

Another option of a fix in that direction would be activating a manual ivp6 like the public one of google http://code.google.com/speed/public-dns/docs/using.html =  2001:4860:4860::8888 and 44

hope this finally helps... hm.

Anyone knows Bertrand Serlets e-mail-adress (I know he left Apple...)? Subject would be "OS X Lion: Let`s talk Wi-Fi"...

Although some nice technical discussions are presented here, you guys are WAY overthinking this. You'll find that laptops with wifi problems have problems with ALL routers both in your office and at open hot spots. This clearly indicates the problem is with the machine not with the wifi base station. Wifi is designed to be robust.

The problem is a Lion bug that hits some machines and no amount of multipath analysis and technical speculation is going to solve it. Wait for the next OS update and save bandwidth.

laechleviel wrote:

 

• Snow Leopard > no problems
• Lion > problems

To repeat it again. Don't mix up the things. The obvious is mostly not the truth.

Also neither the OS Lion nor the 2011 Mac is what happened behind the scene.

Sure, by looking at it from a user point of view the whole thing is crystal clear. For example look at the quote above.

Two little story's to give you eventually an idea...

At the time Windows XP was first massively rolled out on new machines, there where a lot of howling, rant and complaints ...

• Since I've upgraded to XP / Since the new machine our network is terribly slow and sometimes we have literally no connections at all.
• With W2000 / 98 we never had this.
• Have downgraded to ... and our network is fine.
• It MUST be the XP
• It MUST be the new hardware.

And this where not home users with a simple 2 machine net. This where company's had rolled out 400, 600 or 1000 new systems at once.

After a lot of Lab testing's, tech meetings, conferencing with developers and tons of emails the found reason had nothing to do with XP or the hardware.

The used network adapters (NIC's) had a build in auto negotiation for the network speed. With the new drivers delivered with XP these option became active cause more and more networks had not longer only 10 MBit LAN but often mixed 10/100 LAN. Unfortunately most of the used switches at that time could not work proper with that option.

At May/June 2011 I was assigned to support a combined Win7 - Office 2010 rollout to 400 employees at the head office of an industry group. All went well until suddenly department printers vanished from the system settings, printing resulted in a error message or color printing came out black and white. No $50 home printers, high end multifunction network stations, though. The problems show up randomly, not at once and not for all users. Just here and there a single user or a group of users. As you may imagine, there was rant and rave. With my old notebook ... with XP I never had ... with old Office 2003 this never happened ... Win7 is crap.

To make a long story short. The reason was neither in the new notbooks, the Win7 or Office 10. After 4 weeks of troubleshoot the outcome was that a simple outdated part of the print queuing service on the central LAT-servers caused the network trouble.

Lupunus

nipper123 wrote:

 

Wifi is designed to be robust.

As robust as system can be that is supposed to support seamlessly clients with either 1999 802.11a/b; 2003 802.11g and 2009 802.11n, all at once in one single wireless network. Not to mention 10 generations of different wifi chipsets in these machines and the whole crowd of router models.

Lupunus,

I think at this point, you are just trying to deliberately confuse people and prove them wrong. OS X includes drivers for hardware. If Snow Leopard's drivers worked and Lion's did not, the problem is essentially with that version of OS X. Saying it's not the OS but the drivers when in fact, the 2 come together, is really just semantics.

And I don't even think that more nuanced view/explanation of it is correct. If drivers were the root cause, why would my Lion wifi work fine at home? Why would I get the same issues at school with the one SSID/multiple BSSIDs when I took out the Lion wifi kext and replaced it with a Snow Leopard wifi kext?

As for the Office/printing story: I've done more than enough to narrow down what is and is not the cause for me. Do you think I'm just making it up?

wifi dropping now always  and happens more with thunderbolt hdmi in use to my HP 2511x display....  so i think its thunderbolt related too!!!

PLEASSSEEEEE  FIX!!!!!!!!

lupunus wrote:

 

laechleviel wrote:

 

• Snow Leopard > no problems
• Lion > problems

To repeat it again. Don't mix up the things. The obvious is mostly not the truth.

Also neither the OS Lion nor the 2011 Mac is what happened behind the scene.

1. Don`t remember I said anything about the 2011 iMac. I have the mid 2010 model...
2. I am not mixing up anything! It is a matter of a fact that in my case the problems only appear when there is Lion on the machine and that there is no problems when I`m running SL... Of course this is from a  user point of view as I AM A USER!
3. Of course it can be that "behind the scenes" the problems are not caused by mistakes in Lion but by something which works different (but correct) in Lion and awakes mistakes in let`s say the routers hardware or firmware > at the same time it can be also that it`s all about a higher sensitivity of Airport under OS Lion > but if it is about the routers hardware/firmware there should be a lot more users having problems with the FritzBox 7270 and there should not be so many different constellations where the problems appear...
4. End of the discussion for me!!!

I thought I would chime in also; I just bought a MacBook Air 13 i5 and I out of the box, I have been experiencing the WiFi connection issues, droping the signal etc. I thought it was a defective machine until I saw these discussions. BTW, I am using a Netgear dual band router and my MBA almost never sees the 5G band at all. I am very disappointed that Lion is a dud in this manner. If I could, I would have ordered my machine with SL instead since I never trust new OS until it is well used. I guess there is no real fix yet but I will welcome it when it comes.