Thinkpads Forum

I'm having a weird problem with my Z61T.

I have a Buffalo "g" router, recent vintage, that I'm able to use well with other laptops, however, with my Z61T, the signal gets dropped after a while and the only way I can reconnect is if I go to the router and begin "broadcasting" the SSID. Normally I set routers up not to broadcast this as a security precaution, which makes the network invisible to other users or at least to most other users.

Other security parameters include WPA-PSK-AES encryption, and MAC filtering.

After the laptop is dropped by the router, the laptop cannot pick up the presence of the network and hence can't log onto it. My other laptops have been occasionally dropped also but they always see the signal and can log back on easily. The only thing that works with the Z61T is if I start broadcasting the SSID from the router and then, generally, the signal is maintained and not dropped in the first place.

Any ideas on why this might be happening with this latop and what I might do to fix it other than just leaving the SSID broadcast on?

Thanks in advance.

Ken Fox wrote:Other security parameters include WPA-PSK-AES encryption, and MAC filtering.

There is a well known general issue with WiFi connections related to achieving more reliable operation if the SSID is broadcast. Since your WiFi link is secured by WPA-AES, there is not much point in supressing SSID broadcast.

Cheers,

Bill

bill bolton wrote:

Ken Fox wrote:Other security parameters include WPA-PSK-AES encryption, and MAC filtering.

There is a well known general issue with WiFi connections related to achieving more reliable operation if the SSID is broadcast. Since your WiFi link is secured by WPA-AES, there is not much point in supressing SSID broadcast.

Cheers,

Bill

Just because you're not paranoid doesn't mean they aren't out to get you ----

I agree with Bill. If they are savvy enough to even attempt breaking into your WPA-AES they will certainly have no problem sniffing your non-broadcast SSID or spoofing a MAC address.

The afforementioned Buffalo router has given me fits for the two months I've owned it (unlike other Buffalo products I've owned which have functioned well). I've previously had several routers that were set to NOT broadcast the SSID and have not had problems with that. In addition I've had lots of trouble with a Brother multifunction machine that is on the network, and wasted lots of time with brother support that in retrospect was probably due to the router assigning conflicting TCP/IP addresses on the network rather than to a problem with the brother printer/scanner/fax machine.

I had already tried everything imaginable when I called their tech support today, after having become frustrated with connections that never last beyond 2 hours and usually last about 15 minutes. They suggested some other things that were a waste of time (like unplugging wireless phones) which I tried and did not help.

So I reflashed the router's firmware and now it is fried for good. It has an RMA and is going back on Monday. It just needed a little push over the abyss . . . .

I have a cheap Linksys compact router that I bought as a spare and got it out of the basement. It is so far working much better than the twice as expensive router that I put up with for the last two months.

I always make network printers static IP and make sure the IP address is above or below the DHCP pool.

carbon_unit wrote:I always make network printers static IP and make sure the IP address is above or below the DHCP pool.

I think that's a good idea, to make the addresses static. I have done that with this printer at times during what has amounted to a two month ordeal. Sometimes it has worked and sometimes not.

Today, after uninstalling and re-installing this printer's drivers about 5 times, followed each time by runs of CCleaner, I still could not get the printer to function from the desktop even though it works fine from my notebooks. I tried every single possible installation variation for a network printer and none worked. In desperation I spent an hour with regedit and deleted every single reference I could find to any line or folder with the name "brother" in it. I do have serial ghost backups so I knew I could restore the system to an older image if need be.

Everytime I get under the hood of windows XP I'm amazed at what horrible bloatware it is. There must have been several hundred references to this printer in spite of my having uninstalled all its software. (I should add I have a second Brother network printer and I uninstalled that one too, beforehand). Without doubt there were quite a few lines in the registry that regedit would not allow me to delete and a number more that I couldn't find. Of course, the Brother software isn't blameless in this either since it should have uninstalled all this crap in its uninstallation routine as well, and didn't.

I thought that you had to use a TCP/IP address within the DHCP range of the router (or at least within the first 3 sets of numbers, e.g. 192.168.xxx.___) or the printer wouldn't work. What I've done is simply assign an address within the DHCP range of the router, but like 25 numbers up in the range where it is never going to assign anything. Is this wrong?

Ken Fox wrote:What I've done is simply assign an address within the DHCP range of the router, but like 25 numbers up in the range where it is never going to assign anything. Is this wrong?

That will probably be OK but is not deterministic.

For a domestic grade network, what I normally do is set the start of the DHCP assigned range in the router config to (say) 192.168.0.100 and then put the static addressed devices in addresses below that.... so my printers are 192.168.0.7 and 192.168.0.8 etc.

For a typical domestic network, this will definitively keep the dynamic address range from ever accidently overlapping the static assigned addresses.

Cheers,

Bill

bill bolton wrote:

Ken Fox wrote:What I've done is simply assign an address within the DHCP range of the router, but like 25 numbers up in the range where it is never going to assign anything. Is this wrong?

That will probably be OK but is not deterministic.

For a domestic grade network, what I normally do is set the start of the DHCP assigned range in the router config to (say) 192.168.0.100 and then put the static addressed devices in addresses below that.... so my printers are 192.168.0.7 and 192.168.0.8 etc.

For a typical domestic network, this will definitively keep the dynamic address range from ever accidently overlapping the static assigned addresses.

Cheers,

Bill

looks like a good idea. I may hold off doing anything right now since I'm not sure which router I'm going to be using a week or two from now, after I get the RMA'd replacement.

Bill explained it quite well.
The other end of it would be to assign the range to start at 192.168.1.1 and have a maximum of say 50 users. Then the highest number assigned would be 192.168.1.50. You could then put your printer at 192.168.1.200.
Either way accomplishes the same thing. Bill's way is more proper.

carbon_unit wrote:Bill explained it quite well.
The other end of it would be to assign the range to start at 192.168.1.1 and have a maximum of say 50 users. Then the highest number assigned would be 192.168.1.50. You could then put your printer at 192.168.1.200.
Either way accomplishes the same thing. Bill's way is more proper.

The two routers I have (one being dead and going back for RMA replacement) have different address ranges. Buffalo uses 192.168.11.xxx, whereas Linksys uses 192.168.1.xxx

My assumption is that if I set the printers to one of these ranges I'm going to have to change it again in a week or two if I switch routers. Granted, I could put Tomato or some other firmware on to change the router's range, but having already sent one dead router back I don't want to do anything nonstandard for the immediate time period

The 192.168.0.0 address range is by default a /16 or "class B" network, which means that everything with the same first two octets can share a common gateway.

So if your netmask on the router is set to 255.255.0.0 and both routers (are able to) use 192.168.0.1 as their own address, then you should be able to set up the printers with the same static IP regardless of what DHCP range the router is using.

Not that I totally understand everything here, but this is a very interesting and informative thread. I just bought my first router, the D-Link DWL-G730AP Wireless Pocket Router/AP. I'm going to bookmark this thread. Thanks guys, keep talking .

tomh009 wrote:The 192.168.0.0 address range is by default a /16 or "class B" network, which means that everything with the same first two octets can share a common gateway.

So if your netmask on the router is set to 255.255.0.0 and both routers (are able to) use 192.168.0.1 as their own address, then you should be able to set up the printers with the same static IP regardless of what DHCP range the router is using.

To my knowledge, consumer level routers with the mfr's firmware installed cannot change the 3rd octet; you can vary the 4th, as to where it starts and ends, but not the 3rd. So an address of 192.168.0.xxx would be impossible to set (or would not be accessible) within the range for the router to use in the domain (am I using the term "domain" properly?). Of course most anything is changeable with DD-WRT, Tomato, and the other proprietary firmwares out there.

This means that if I set my printers within the range set by the router, either 192.168.1.xxx for the Linksys or 192.168.11.xxx for the Buffalo, that I'd have to change those addresses to be within the domain if I change routers. Is this correct? It has been my assumption for as long as I've owned routers.

Ken Fox wrote:To my knowledge, consumer level routers with the mfr's firmware installed cannot change the 3rd octet; you can vary the 4th, as to where it starts and ends, but not the 3rd. So an address of 192.168.0.xxx would be impossible to set (or would not be accessible) within the range for the router to use in the domain (am I using the term "domain" properly?).

Back when I had a Linksys WRT-11 home wireless (now running with a Proxim AP-600 and a PIX ...) I was able to change the access point's IP address and subnet mask -- I use 172.16.0.0 at home. I just checked on a current WRT-54G, and it allows the same. I don't know about Buffalo, though.

Ken Fox wrote:To my knowledge, consumer level routers with the mfr's firmware installed cannot change the 3rd octet; you can vary the 4th, as to where it starts and ends, but not the 3rd.

I have had ocassion to configure a variety of domestic grade routers over recent years and have had no problems with configuring the all the octets to whatever suited the circumstances at hand.

Cheers,

Bill

Ken Fox wrote:To my knowledge, consumer level routers with the mfr's firmware installed cannot change the 3rd octet; you can vary the 4th, as to where it starts and ends, but not the 3rd.

I change the third octet quite often as most of the broadband providers here want their equipment to be 192.168.1.1, So I change the Linksys WRT54G routers to 192.168.2.1 but sometimes I change them to 10.x.x.x or 172.16.x.x depending on the existing setup. Most Netgears will do this too.