I'll try to be thourough without writing a novel! I have a Zyxel Prestige 660HW-61 wireless router that connects wirelessly (sometimes) with a Windows XP SP2 desktop via a Belkin F5D7001 PCI Card, a Toshiba laptop with built in wireless, and an Apple G4 Powerbook. I use the XP desktop the most often therefore have most problem with it. However, all computers will lose connection at one point or another.
Regarding the desktop, the wireless connection seems to drop about every 20-30 minutes or so. Sometimes it's more frequent. I know the frequency because I use (or try to use) Skype frequently and conversations last only about that much time before being dropped. Also, the wireless network connection icon will sometimes come up and say "Limited or no connectivity, You might not be able to access the internet or some network resources. This problem occured because the network did not assign a network address to the computer." At this point if I click repair, then it disables the connection, re enables the connection, and assigns an IP address, then all is well again until the next time.
On the other hand, it I connect my Powerbook to the router via CAT 5 cable, everything seems to be fine and the connection stable for many minutes. I'll sometimes use Skype on the Powerbook this way to keep connection from dropping my calls. Unfortuantely, this is not the most convenient way to do things. Besides, that's why I went wireless!!
I've been told that there are probably interference problems, but I just don't buy it!! The problem is just too frequent and seems to have some sort of pattern to be interference. Can anyone suggest anything I can modify/check/troubleshoot in the router? The firmware is the most recent and all the other settings seem OK. Please help, I'm about the chuck this thing out of the window!!!! Thanks.......Dan
Duane, I went through and made sure WZC was disable and it was...kind of. It showed stopped but startup was still set to automatic. I have changed it to disabled, so hopefully this will have a positive effect! I didn't flash the firmware but confirmed that it was most recent. Also, I did reinstall the driver......even reformatted and reinstalled windows to start fresh with the connection. I'll see if the WZC change helps at this point and keep you posted. Thanks for the feedback!!!
Bill, router seems to be in OK place, that is, on open table with good airflow around it. Made a change to WZC as Duane suggested, so I'll see what that does. Thanks for the info and I'll keep you posted.......Dan
Just a random hardware thought: Is the router getting enough cooling airflow? Sometimes these little boxes get stuck in places where they can overheat...
I'm not sure why you are discounting interference, are there no cordless phones or microwave ovens in your (or your neighbors') house(s)? You could try changing the channel to one of the non-overlapping ones {1,6,11}.
And, as Duane said, check the network settings and that you are using the latest drivers, and remove all extraneous WiFi networks.
Maybe, the XP O/S is trying to roam and trying to connect to other networks in your area dropping your connection. Have you considered that if you have not set the preferred network the O/S and card are to stay locked in on? Have you tried disabling the Wireless Zero Configuration Service on XP that makes the O/S roam with the card?
Have you reflashed the router with the firmware? It might correct the problem. Have you tried reinstalling the driver for the card?
Model of Toshiba laptop and what model wireless card is installed?
What happens if you do nothing after it disconnects? Does it reconnect automagically? Most wireless clients will do this if interference is bad enough to cause a disconnect. However, the "limited connectivity" message that Windoze wireless zero config generates does not mean that it has just lost the connection. It means that it has recognized that the connection was lost, attempted to reconnect, attempted to get an IP address via DHCP, and failed miserably. In traditional Microsoft wisdom, it doesn't retry after it has failed once. Please disable WZC and see if the Belkin or Toshiblah software can do a better job of recovery.
I'm lost. You say the desktop disconnects every 20-30 minutes or so. Then you switch to a Powerbook G4 laptop with a wired connection. The Toshiba isn't even mentioned. Can we get this organized please? Something like a table:
Device Wireless card Symptoms Desktop F5D7001 PCI disconnects every 20-30 mins Toshiba ?????? ??????? Mac G4 ?????? ???????
What happens when you connect the Desktop directly to the 660HW-61 router with a CAT5 cable? Same with the Toshiba laptop? Make sure the wireless is disabled when you test this. If the G4 does not have wireless, leave it out of this test. If it does, include it.
The Zyxel 660HW-61 appears to be a Eurpean only model (not sure). Do you have the country properly selected?
The 660HW-61 supports 125Mbit/sec wireless. Turn OFF this feature for now and stay with standard 802.11b/g. If there are any other added wireless or RF related features, also turn them OFF for now.
Are you 100% sure that the "disconnect" problem is wireless related? The various connectivity tools that are part of the wireless client and drivers will show a loss of connection. The "Limited or No Connectivity" message is sufficient. I just want to be sure you're not dropping the ADSL connection.
Do you have any 802.11b devices or are they all 802.11g? If there are no 802.11b devices in your network, turn off 802.11b compatibilty in the 660HW-61.
It might be interference but your description is insufficient to offer more than a guess. Does it disconnect EVERY time 20-30 minutes after connecting? Or, is it just coincidence? Have you tried moving the wireless devices fairly close to the 660HW-61 so that the effects of interference are somewhat less? It takes a substantial amount of interference to produce a disconnect with a strong signal.
The correct term is "defenestration".
My guess(tm) is that turning off the 125Mbit/sec turbo afterburner speedboost fire belching wiz bang enhanced plus feature should fix the problem.
Flashing the router with the firmware is like doing a reinstall, which could correct a problem if something has gone wrong. No program is perfect.The reflash may or may not improve the situation.
The default rekey interval is usually 3600 seconds or 60 minutes. If it disconnects every 20-30 minutes, it's not the rekey interval unless he uses WPA-PSK and had been tinkering with the settings.
Jeff, thanks for all the great information. OK, I'll try to break things down for you: Windows xp pro SP2- disconnects every 20-30 minutes. Right now don't have a cat5 cable long enough to reach the desktop, but signal is always shown minimum good and most of the time excellent.
Apple G4 Powerbook OSX panther disconnects maybe once or twice in a full day of use, but not nearly as much as the xp desktop. The reason I connected this directly to Zyxel via cat5 was to make sure it wasn't the dsl dropping. I used skype for about 2 hours with no problems this way, so seems to be a wireless issue, not dsl.
Toshiba laptop uses windows xp home SP2. Not sure of the model, cause it's out on a trip right now! It also displays the same problems as the desktop i.e. dropping connection every 20-30 minutes or so. Also connected this machine directly to router via cat5 and had no connection problems.
All computers have g capability, so I turned off the b feature so it wouldn't possibly pick up another wireless b device that might slow whole network down. I don't know if that can happen if the device isn't "connected" to the network, or if just by picking up the signal, it can slow the network down.
Yes, this is a European model (I'm here right now) but correct country is connected.
I completely disabled WZC so that might improve things.....I'll let you know.
It seems that the connection will come back after about 5 minutes or so, but it comes back almost immediately if I "repair" the connection via windows.
The router is set with wireless port control auth required, reauth timer 1800 sec, idle timout 3600 sec, key mgmt protocol wpa-psk,wpa mixed mode NOT ckecked, group data privacy tkip, wpa group key update timer 1800 secs. So anything there you see is not correct??
Frank, good article ...thanks! If there is a known problem then I might just send it to zyxel and tell them to fix it or refund my $$! I have a netgear at my condo and have never had connection problems. This Zyxel came as the modem/router of choice of the DSL provider Tele2. Maybe they should refund my $$$? Oh well. Not sure if it applies to my settings though. here's what I have:
The router is set with wireless port control auth required, reauth timer 1800 sec, idle timout 3600 sec, key mgmt protocol wpa-psk,wpa mixed mode NOT ckecked, group data privacy tkip, wpa group key update timer 1800 secs. So anything there you see is not correct??
Any chance you have the above link going to an english site? thanks again.....dan
Frank found the answer. It's the WPA-PSK encryption rekey interval, which is set to 1800 seconds (30 minutes). Apparently it's a bug and Zyxel's problem. If you want to experiment, I suggest you dive into the router configs and change the rekey interval to something like 120 seconds (2 minutes). If you now start seeing disconnects every 2 minutes, that verifies the problem.
I'm not sure what to recommend as a workaround. Increasing the rekey interval just delays the problem. Switching from WPA-PSK to WEP is a serious loss in security, but might be a good alternative until Zyxel produces a fix.
Well, if you had a CAT5 cable, it probably would have worked just fine as there's no encryption or rekeying happening with a direct connection. The idea was to take the wireless out of the picture temporarily.
Hmmmm... If it's the rekey interval, the dropout times should be exactly the same and rather consistent. I gotta read up on TKIP to see how the rekey interval works. Right now, I have a cold, my brain feels like mush, and I don't wanna do much reading.
Agreed. Good troubleshooting.
OK, that's two computers out of three that work directly, so it has to be the wireless. I like isolating problems by substitution.
The 802.11b compatibility feature requires only one 802.11b packet heard to slow the 802.11g transfers down to a crawl. If the neighbors are using 802.11b, your 802.11g speeds will suffer. Best to leave it at "802.11g only" if you have no 802.11b devices on your network. The only problem is when you have visitors bearing 802.11b devices.
Ok, that eliminates that problem. I've read somewhere that some routers seem to have a "feature" that refuses to allow connections from clients that have a different country code. I don't know if this is a feature, and accident, a rumor, or a regulatory requirement. Treat it as a rumor for now.
It's worth a try. However, that will not do much for the same problem in the G4 Powerbook. I have no idea whether it's better to use WZC or the manufacturers drivers. I've played with it both ways and found that on some devices (i.e. Linksys devices) WZC literally fights the driver and must be disabled. On other machines, it works just fine. If your Toshiba laptop is fairly new, it probably came with their network config and diagnostics tool (I forgot the name) which offers a nifty looking graphics front end for wired and wireless configuration. It also takes care of autoswitching between wireless and wired networks, offers some tolerable diagnostics, and has a nifty "radar-like" display of wireless access points found. However, it will do nothing for the current problem other than add another layer of complexity. Oh well.
Looks fine. In retrospect, I can't tell if it's the re-auth interval or the re-key interval that's the problem. Try lowering each, one at a time, to about 180 seconds (2 minutes) and see which one is the culprit. Whichever it is, the problem is in Zyxel's firmware and I don't think juggling the setting will do much more than delay the disconnects.
Incidentally, such exercises is one reason that I fail to appreciate all in one, integrated modem/router/wireless contrivances. They are cheaper and in one case (direct access to DSL modem diagnostics) are better, but they are hell when something goes wrong. If you had purchased 3 separate boxes, (modem, router, and access point), the problem could have been solved by simply replacing the relatively inexpensive access point, with a different one, and left the DSL modem and router alone. Instead, you may find yourself replacing everything. There are also some other reasons for why I like component systems, but they are not relevant to this problem.
Jeff, it looks like the problem is in the re-auth interval!! I changed settings and almost on cue, the connection was lost as the time I set came up. I have contacted Zyxel and informed them of the problem with the question of does new firmware correct the problem or what do I have to do to get a refund on the router? Basically not giving an option for this problem to continue!! We'll see what they say, but in the meantime, thanks for the help on this! I have one other question that I'll post separately regarding speeds.....Thanks again. Dan
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