For the Mac network techies

[yendi]

About two weeks ago, Elayna's laptop stopped connecting regularly to the network. Today, 'song's started doing the exact same thing. Both drop the wireless connection, timeout when trying to reestablish it, and pretty much won't work for more than a few seconds.

They're both on 10.5. My laptop (on 10.6), and the XP netbook connect just fine.

Anyone out there a solid expert on MacOS networking and know of any potential solutions here? I've tried zapping the pram, turning Airport off and on, and a handful of other things, to no avail.

ETA: Also, since I know this is a known issue on the MacBook pro line, the issue is NOT because of them being on battery power.

Comments

[amokk]

What kind of router is it? Is there any new wifi in the area? Get iStumbler and load it on all the laptops and check your signal strengths in various areas. Also use it to make sure your router is on a different channel than any other wifi in the area.

Find your router docs and do a hard restart. If you have your settings written down (WEP password you use, or whatever), you could also try a factory reset.

Otherwise you might try changing either the radio mode (from 2.4Ghz to something else the router/laptops can handle), and drop security (no WPA keys, no password, open broadcast the network). It's odd but sometimes the security is twitching something.

We have an Airport Extreme base station, and I've had to occasionally boost the signal to 100% (the multicast rate and transmit power) during some times of bad interference.

We've had "random drops" before, I never actually figured them out. They eventually "disappeared", although my wife's laptop still has slow internet issues occasionally. And come to think of it, the iMac (PPC G5 running 10.5) was having drop issues and it was in direct line of the router, never figured that one out either.

this is what worked for me...

[coffeehouse.livejournal.com]

I assigned each laptop and iMac a perm IP address since the printers, Xbox, Wii and PS3 are all wireless as well. Seemed to have solved the issue in my middle of the block rowhouse trinty with 7 wireless networks (my neighbors) of four bars each are also being scanned within a 500 foot range of me.

[yendi]

I'll give some of those a shot. One thing I forgot to mention is that they're both failing to find any wifi networks, not just ours.

[theweaselking.livejournal.com]

When I experienced this, it was with three Macbook Pros - and not only would they drop, but they would DOS everything around them as they tried to reconnect.

With all three, it started with OSX 10.5, and the only fix we ever found was "install 10.4 and deal" or "go wired".

(10.6 didn't exist then, of course)

amokk's advice is generally good - reset the router, try without encryption[1], change channels, change encryption type[1] - but when I last had this problem, I never found a solution. (I also don't work with a lot of Macs.)



[1]: Both of these are TEMPORARY tests. Even if the problem goes away with WEP or WPA/TKIP or no encryption, you can't leave 'em that way. You *have* to put it back on WPA/AES unless you want your teenaged neighbour to use your internet access for torrenting porn and to read all the files on your laptop.

[unblinkered.livejournal.com]

My MacBook has started doing this, too....and just after installing an AirPort update. Apple Store maintain it's a problem with out router, but I've done a hard restart as suggested with no effect and it's doing it with all the networks I use. I'm going back in tomorrow to wave money at them (as in, I'll buy an Air if we can get this resolved) in the hopes it'll make them look harder. Shall report back if I get anywhere with it...

[tewok.livejournal.com]

Really, you should be using WPA2. I'm pretty sure WEP is breakable in seconds, and I think I read that WPA doesn't take terribly long to break either.

[theweaselking.livejournal.com]

WEP usually takes longer than "seconds", but it's trivial. WPA/AES is reasonably secure. WPA/TKIP is insecure if the passwords on your devices are insecure - TKIP allows the kind of injection attacks that might let an attacker *steal the key from the router by logging in*.

WPA versus WPA2 are implementation details - and WPA2 doesn't allow TKIP, which makes it harder to do wrong. But WPA/AES and WPA2/AES are basically equally as secure.

You SHOULD use WPA2 if all your devices speak WPA2 simply on principle, but WPA is perfectly good if you configure it to use AES only and not TKIP.

[amokk]

Or just use MAC address access, if there aren't too many wireless devices in the house.

[slipstreamsurfr.livejournal.com]

question, are they running hot? I've seen some of them start this trick if the cooling gets messed up. They get hot, then the airport starts cycling..

I'm having a similar problem though with my macbook pro now, started about 3 months ago now. My airport doesn't cycle off and on, the icon stays solid with full bars, but it'll just stop receiving packets... Sometimes toggeling it off and back on will settle it down. The xp box in the house doesn't have the same problem though. I have replaced my airport express at least once over this issue thinking maybe it was my router. Nope...

[theweaselking.livejournal.com]

I hate relying on that, and I find it annoying as fuck every time I add a new device - which is MORE annoying if it only happens once a year or so, because by then I've forgotten.

Far better to just use DHCP, a nice long secure WPA passphrase, and accept that Macbooks running 10.5 are crappy and unreliable.

[grntserendipity.livejournal.com]

What OS. My partner had snow leopard, and it started doing the same thing. We had to go back to 10. Whatever.

[grntserendipity.livejournal.com]

I fail at read comprehension when sleep depped. Is there anyway to get them on 10.6?

[tewok.livejournal.com]

I don't remember the exact numbers, but I'm pretty sure WEP is under a minute.
I think WPA was under five, maybe ten, minutes but I'm not sure.

(Not disputing anything you've said, just adding hard, cold, speculative semi-memories my less-specific previous post.)

[theweaselking.livejournal.com]

"WPA" is not inherently more crackable than WPA2. They are the same algorithm, by slightly different methods. What matters is that WPA allows TKIP (which allows vulnerability in the case of an insecure device password) and WPA2 does not allow TKIP, which means that a less-secure device password is not a vulnerability as long as the wireless key itself is secure.


Basically, assume that you set up WPA/TKIP with the passphrase "ph*YaS&U@rE4pAMp3e3atREMEgUW-6". This is not conventionally crackable. However, if you left your Linksys router with the username "admin" and the password "password" (the defaults), the fact that you were using TKIP would allow me to log in to your router and learn the passphrase, and then log in as a legit user and do whatever I wanted.

If you were using WPA/AES with the exact same router and passphrase, I'd be completely fucked and entirely unable to get into your network.

If you had changed the admin username and password on your router to something 40-characters long, I would be TECHNICALLY capable of brute-forcing it even if you used TKIP, but it would take longer than the heat death of the universe.

WPA2/AES does not make a difference, compared to WPA/AES. The main difference is that using WPA2 means you CANNOT use TKIP, and TKIP is the problem.


WEP's cracking times depend on the hardware and the software involved. If you can inject packets and the target network doesn't detect the injection, under a minute is doable. WPA cracking depends ENTIRELY on the use of TKIP rather than AES, and the device passwords inside TKIP being insecure. If you use AES instead ot TKIP, or if the passwords of ALL the internal devices are all secure and long and random, WPA is as secure as WPA2.

[amokk]

Yeah, I found that out when we turned on our Nintendo DS and iPod Touch and hey look the Wii has wireless and...

Yeah. ;)

My WPA2 password is the minimum length required by my old xbox router (it required it to be 13 characters, and which I no longer use but the password was set) and had to change a special character because our wireless printer didn't support it (how odd).

And yeah, there seems to be a theme with 10.5 there.

[theweaselking.livejournal.com]

My advice for wireless passphrases has always been to pick a nice long movie quote where the SSID will remind you of it, but the quote itself is 25+ characters long, is not immediately obvious given the SSID, and is thus not brute-force or minimal-knowledge vulnerable. This avoids most of the special-character and minimum-length restrictions.

And I am not a fan of paying Mac prices to get Mac performance, but even given that, OSX 10.5 and wireless connections are REALLY not Apple's high water mark. Once again, I'm not Apple's target audience and I don't fix a lot of Macs, but I've encountered three different Macbook Pros that worked with 10.4 and had their wireless die with 10.5, and the problem was repeatable if you swapped .4 to .5 and back again. And, y'know, a little trivial Googling showed me I wasn't in the slightest the only person to have that problem.

[theweaselking.livejournal.com]

PS: Worse than an unmemorable passphrase is a network that doesn't use DHCP. When you add a new node once a year or so, and you deal with that specific network only rarely? Remembering the network settings and that this network needs those settings is a real pain in the ass. Especially when the new node is something like a credit card processor, and you don't get called until the client has already followed the instructions from the credit card company, which assume the network is using DHCP, etc.

[ardaniel]

I have long suspected that the Atheros driver in later revisions of 10.5 is utter crap. My old MBP with an Atheros wireless chip developed that issue; Apple repaired the AirPort subsystem entire, antenna included, to no avail. Upgrading to 10.6 fixed it.

(The GPU shat the bed on that machine too at some point, and I got an entire logic board out of that. The 2007 MBPs were... touchy.)

[isomerica.net (from livejournal.com)]

If you care about actual access control vs. "security through being more difficult than the neighbor's wireless" FYI:

MAC address access is completely insecure. All you need to do to gain access is to start a wireless sniffing program, look for mac addresses of other devices currently on the network, and change your MAC address to match one of them. This is trivially easy (even easier than cracking WEP). Having a duplicate MAC address presents surprisingly few problems on a typical home network.

And of course none of your communications are encrypted so someone with a sniffer can see everything you browse unless you are using HTTPS (SSL), see all instant messages, etc.

[amokk]

There's always that.