[FrancesHinden]

At home, we have cable broadband delivered by Virgin Media. There are five different computers (4 pcs of various ages and flavours of windows, 1 Mac) that connect to it more or less regularly, plus occasional visitors.

We used to have a wireless g router on which we used no security, but instead had a list of physical mac ids which were allowed to connect.
We recently bought a wireless n router and use the wpa2 security it provides. This is much faster (as you might expect) although it takes a few seconds longer to connect, I assume because of the security.

But now I have a new problem. All the PCs are fine with it.

On the Mac only, which is the newest of the five (it's a MacBook Air, bought about two years ago) it reasonably often gets into a mode where every 5 minutes or so it loses connection and I have to turn the AirPort off and turn it on again. That immediately fixes the problem. This is pretty irritating when it happens so frequently. What is strange is that this happens

• Nearly (not not quite) every time I use the BBO forums
  
• Sometimes when I am browsing the internet, but much less often
  
• Never when playing/watching on BBO using the web client

I don't post regularly in any other forum.

It doesn't happen with any other computer in our house.
It doesn't happen on the Mac when it is taken somewhere else (various houses, hotels, airports etc have all been fine, using all sorts of different types of wireless security)
It doesn't happen on the Mac when I connect with a network cable rather than over the wireless

It seems to be unrelated to the number of other computers on the network at the same time.

I have tried using a different browser (firefox rather than safari) with the same problem. Other pcs in this house use firefox without this problem.

So it seems to be a combination of this computer + BBO forums + our wireless connection.

Any ideas? I haven't yet tried fiddling around with the router - changing channel, changing security etc because it's a bit of a pain to do so, although that's obviously the next step in the diagnosis if no-one can say "oh yes I recognise this problem, this is what you have to do".

[Antrax]

Have you fiddled with any QoS settings on the router? It's a long shot, but the only other idea that comes to mind is some issue with the MAC's network software stack.

[jallerton]

Antrax, on 2012-September-16, 05:18, said:

Have you fiddled with any QoS settings on the router? It's a long shot, but the only other idea that comes to mind is some issue with the MAC's network software stack.

What are the QoS settings?
What is the MAC's network software stack?

[barmar]

jallerton, on 2012-September-16, 07:57, said:

What is the MAC's network software stack?

It's the OS software that manages the network.

Is your router multi-mode, i.e. does it also have wireless g? Try enabling that, connect the MacBook to the g network, and see if you still have a problem. I suspect most of the public wireless access points you've tried are g, not n, and maybe the MacBook is having problems with n.

I have no idea why the BBF would trigger the problem, we're not doing anything network-wise that's different from any other web site. Sometimes hardware problems are sensitive to particular data patterns. I remember many years ago I was working at an ISP, and a customer reported that they couldn't download certain files, and when we did a packet capture we saw that they always got stuck on a packet that had a particular arrangement of bytes, and their modem was corrupting it. These types of problems can be almost impossible to diagnose, because there's no obvious "cause" except that the packet being received doesn't match what was sent.

[Antrax]

"QoS" stands for "Quality of service", which is a feature in routers which lets them prioritize certain computers or types of connections (protocols) over others. It's off by default, so if you haven't touched it then it probably isn't the problem.
The other idea is what barmar said, that maybe there's some weird bug in MacBooks in conjunction with using wireless N. The good news is that if that's the problem, Google should be able to show it, since your MacBook is identical to many others around the world. The bad news is that if that's the problem, other than what barmar suggested, it's unlikely you could find a solution - you can't update drivers or something in a Mac.

And sorry for the brevity of my previous post, from your OP it sounded like you're well-versed in technical matters.

[barmar]

Are you running Mountain Lion on the MacBook? Google "mountain lion wireless issues" and you'll see that this is a common problem, and there are some suggested solutions.

[FrancesHinden]

no it's snow leopard 10.6.8 but googling 'snow leopard wireless issues' also gets lots of hits.
I'll work through some of the suggestions.

the new router is 'n' only. That made it cheap.

Today the connection is fine....

[FrancesHinden]

I doubt anyone is particularly interested.. but I have found a workaround.
All the various things I tried didn't fix the problem, but as long as I am logged on to BBO, I never lose connection.

So I just stay logged on (doing nothing) and everything works fine!

[cherdano]

FrancesHinden, on 2013-January-26, 06:19, said:

I doubt anyone is particularly interested.. but I have found a workaround.
All the various things I tried didn't fix the problem, but as long as I am logged on to BBO, I never lose connection.

So I just stay logged on (doing nothing) and everything works fine!

Sounds like it disconnects when the connection is unused for a while.

[cherdano]

FrancesHinden, on 2012-September-17, 14:29, said:

That made it cheap.

Maybe not the best priority

I have had success improving wireless connectivity problems just by switching them to a different channel. Not sure this still applies to modern routers, though.

[FM75]

If it really happens nearly every time you connect,
then I would try installing Fiddler 2 (free) on the newest PC you have.

Once you have installed it, you can search google for how to
make it a "proxy" for your Mac (or iPhone, PC, or any other devices).
When you have installed it correctly, and configured your Mac to use it,
your Mac will make all http/https requests through Fiddler2 running
on the PC (yes, it has to be running, of course).

Traffic in both directions can be recorded. You could even save a
whole set of transactions into a file.

Don't open any other apps that access the internet, gmail, etc, or you
will get loads of irrelevant traffic. You can filter out certain stuff.

Will it be easy to find the problem? Not likely, even if you have a good
knowledge of how http works. But it is the equivalent of the sniffer
mentioned earlier.

It seems very strange that the Forum would be the only thing that
causes a problem AND that it only happens on the Mac. Web browsing
is all http. Posting is http. The same traffic is going to go through the
router regardless of the computer, except for some minor differences in
headers that the various browsers supply to the server. But it would use
the same headers for all sites, not just BBO Forum.

I use an iMac, iPad, and new MacBook Pro (and before that, an old one).
I may lose connectivity briefly at some points in the house, but that is independent
of the internet host.