Problem with wireless access point(?)
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi gang, I just purchased a Linksys WRT54GL wireless access point. Currently, it is running the stock firmware (upgraded to the latest version). I may put Linux on it sometime in the near future. While I can get connected to it with my Linux laptop, I notice that file transfers start at a screamingly fast rate, and within a minute or two, drop to barely a trickle. When I used an entirely hard wired connection, I have no such problem. Has anybody else noticed this with the Linksys WRT54GL? If so, will the Linux software solve this problem? I don't believe that the problem lies with the wireless hardware/software in my laptop since I have used it on other wireless access points without problems. Thanks, Andy - -- Andy Stewart (KB1OIQ) Founder: Worcester Linux Users' Group Founder: Chelmsford Linux Meetup Group President: PART of Westford, MA (WB1GOF) -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFLOmdpOjiraCaOTOoRAqsRAKDjaKrNykXKburz0IozXi8bQn1nfACgj66G oJqD9jfjXolyrVPLN3lDFOY= =6xJa -----END PGP SIGNATURE-----
Andy> I just purchased a Linksys WRT54GL wireless access point. Andy> Currently, it is running the stock firmware (upgraded to the Andy> latest version). I may put Linux on it sometime in the near Andy> future. Heh, isn't the stock firmware Linux of some sort already? *grin* Andy> While I can get connected to it with my Linux laptop, I notice Andy> that file transfers start at a screamingly fast rate, and within Andy> a minute or two, drop to barely a trickle. What does 'netstat -ni' say during this time? What protocol are you using to copy the file? Are you seeing funky ping times? Any dmesg info? What hardware are you using on each end? What does tcpdump say during the transfer? Are you seeing dropped packets? What wireless hardware is in your laptop? Do you have security on? What happens if you turn off all security? Andy> When I used an entirely hard wired connection, I have no such Andy> problem. It's almost certainly something with the wireless network, but it's not clear where. Andy> Has anybody else noticed this with the Linksys WRT54GL? If so, Andy> will the Linux software solve this problem? You could try the 'tomato' or ddwrt (ddrwrt?) firmwares. But I think we need more details first. Andy> I don't believe that the problem lies with the wireless Andy> hardware/software in my laptop since I have used it on other Andy> wireless access points without problems. Could be anything. After you upgraded, did you do a full reset of the WRT54GL and then re-configure to your settings? Good luck! John
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 HI John et al, There were a lot of suggestions in your email - thanks! I'll need time to try them out. I'll report back when I get more data. Thanks again, and Happy New Year! Andy - -- Andy Stewart (KB1OIQ) Founder: Worcester Linux Users' Group Founder: Chelmsford Linux Meetup Group President: PART of Westford, MA (WB1GOF) -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFLOpuYOjiraCaOTOoRAnJXAJ9oqTAL9SjQKY8G9K3X06vY7HbX0gCeO1BI RaozqrEjetmfoFlCfKDgSyI= =kHMx -----END PGP SIGNATURE-----
Andy> There were a lot of suggestions in your email - thanks! You're welcome! Andy> I'll need time to try them out. I'll report back when I get more data. Good luck with it. Also, more info that would be nice to know: distro, version, kernel version, modules loaded, etc. You might be using old drivers, etc. John
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 John Stoffel wrote:
Andy> There were a lot of suggestions in your email - thanks!
You're welcome!
Andy> I'll need time to try them out. I'll report back when I get more data.
Good luck with it.
Hi gang, OK, I think I have succeeded in fixing the problem. Here's what I did: a) reset the Linksys box b) picked a new radio frequency that does *not* have interference issues with my 2.4GHz wireless telephone...(I haven't tried the microwave oven yet...). c) insured that the Linksys box was in Gateway mode (vs. router mode which seems not to work for me). After doing these three things, my laptop with 802.11g capability can download files off of my server at a sustained rate of 13Mbits/sec according to iptraf, or 1.4Mbytes/sec according to sftp. This is one laptop doing one download, no other computers on the wireless network. This is *much* faster that what I was previously able to sustain. On my older laptop with only 802.11b capability, by itself, I repeated the same experiment and saw a rate of 425Kbytes/sec according to sftp, or 3.7Mbits/sec according to iptraf. With both computers downloading simultaneously, the wireless net naturally downshifted to the lower speed. When I turned off the download on the slower computer, the speed quickly increased for the faster laptop. The aforementioned data rates have been sustained for at least 15 minutes, where before, I couldn't do this for even 1-2 minutes. I think I can declare victory. Thanks for the help! Happy New Year! Andy - -- Andy Stewart (KB1OIQ) Founder: Worcester Linux Users' Group Founder: Chelmsford Linux Meetup Group President: PART of Westford, MA (WB1GOF) -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFLPDHrOjiraCaOTOoRAhGOAKDGbFyuNUwoNtBZyP8pqEA9yUUFIwCgmP4n m+svFxGvxXhKue9emJlWjG8= =/Mkl -----END PGP SIGNATURE-----
I have a question for Andy and then one for Karl. Andy:
b) picked a new radio frequency that does *not* have interference issues with my 2.4GHz wireless telephone...(I haven't tried the microwave oven yet...).
What freq did you find that the 2.4GHz wireless telephone did not interfere with? What channel did you finally end up using? ---------------------------------------------- Karl had posted an answer about the Linksys (under the subject line "Re: [Wlug] Wlug Digest, Vol 74, Issue 13") One comment in there I found very interesting:
Now this is going to blow your mind, but if there is ANY difference in the Workgroup name between the router and the computers, it causes the router to "restrict" bandwidth.
Does this only apply to various forms of filesharing, or to all wireless traffic through the WRT54GL? I (and my housemates) are not doing big downloads, and not using Samba. Maybe one of the Windows PCs here might occasionally d/l a movie. But in experimenting with wireless here, using one or other of my Debian PCs, Tomato on the Linksys, I also thought the wireless worked rather slow, even though we have a +20MBps connection. Mostly what I was doing was browsing. Do all computers using wireless here have to belong to the same Workgroup, no matter what kind of internet traffic they're doing? If I do need a Workgroup name for the router, how do I do that? Thanks, Liz J
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 E Johnson wrote:
I have a question for Andy and then one for Karl.
Andy:
b) picked a new radio frequency that does *not* have interference issues with my 2.4GHz wireless telephone...(I haven't tried the microwave oven yet...).
What freq did you find that the 2.4GHz wireless telephone did not interfere with? What channel did you finally end up using?
Hi Liz, My telephone caused problems on Ch 1 and Ch 2, but Ch 3 is OK. Here's how I figured this out. I setup the network on Ch 1 and got some downloads working well. Then, I turned on the phone and immediately saw the wifi come to a screeching halt. Turn off the phone, and the wifi bounces back. One can see this with the ping command as well. I had been using Ch 10 with unpredictable results. It turns out that one of my neighbors is using Ch 10. In addition, I ran kismet and sniffed the local wireless networks. I can see networks from 3 of my neighbors. Ch 3 is not in use by any of them. Happy New Year! Andy - -- Andy Stewart (KB1OIQ) Founder: Worcester Linux Users' Group Founder: Chelmsford Linux Meetup Group President: PART of Westford, MA (WB1GOF) -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFLPNOBOjiraCaOTOoRAgglAJ9KpXpYYu1MUKcKhjfB/PyplrV/fwCeO+ja 4pxMQW08B6JSGMFYOPaFo98= =3aVW -----END PGP SIGNATURE-----
Thanks Andy. For clarification:
Then, I turned on the phone and immediately saw the wifi come to a screeching halt.
turned on -- Did you initiate an actual phone call (TX & RX sigs) at this point, or do you mean that you plugged in the telephone base unit to the power and the phone line?
In addition, I ran kismet and sniffed the local wireless networks. I can see networks from 3 of my neighbors. Ch 3 is not in use by any of them.
Tomato on my Linksys will detect nearby wireless sigs & indicate what channel they're using, plus several more details about them. My Linksys has about 16 MD of memory, long may it live. TY Liz
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 E Johnson wrote:
Thanks Andy.
For clarification:
Then, I turned on the phone and immediately saw the wifi come to a screeching halt.
turned on -- Did you initiate an actual phone call (TX & RX sigs) at this point, or do you mean that you plugged in the telephone base unit to the power and the phone line?
Hi Liz, I specifically removed the handset from the base of the telephone and turned on the handset. That allows me to hear the dial tone, which I'm sure causes a radio signal to be initiated between the handset and the base.
In addition, I ran kismet and sniffed the local wireless networks. I can see networks from 3 of my neighbors. Ch 3 is not in use by any of them.
Tomato on my Linksys will detect nearby wireless sigs & indicate what channel they're using, plus several more details about them. My Linksys has about 16 MD of memory, long may it live.
I have seriously considered putting Tomato on my WRT54GL but I haven't done it yet. HTH, Andy - -- Andy Stewart (KB1OIQ) Founder: Worcester Linux Users' Group Founder: Chelmsford Linux Meetup Group President: PART of Westford, MA (WB1GOF) -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFLPSLLOjiraCaOTOoRAjEXAJ4u7bezzZ45bQyE07/G+0WExk+x3wCg3N7u BkCUqxGoHYW9yVJkHKeEC8g= =lT55 -----END PGP SIGNATURE-----
On Thu, Dec 31, 2009 at 5:08 AM, Andy Stewart <andystewart@comcast.net> wrote:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
John Stoffel wrote:
Andy> There were a lot of suggestions in your email - thanks!
You're welcome!
Andy> I'll need time to try them out. I'll report back when I get more data.
Good luck with it.
Hi gang,
OK, I think I have succeeded in fixing the problem. Here's what I did:
a) reset the Linksys box
b) picked a new radio frequency that does *not* have interference issues with my 2.4GHz wireless telephone...(I haven't tried the microwave oven yet...).
I've never been able to find a channel free from microwave oven interference, sadly. I'm convinced my ancient microwave puts out a wide spectrum and leaks plenty.
c) insured that the Linksys box was in Gateway mode (vs. router mode which seems not to work for me).
After doing these three things, my laptop with 802.11g capability can download files off of my server at a sustained rate of 13Mbits/sec according to iptraf, or 1.4Mbytes/sec according to sftp. This is one laptop doing one download, no other computers on the wireless network. This is *much* faster that what I was previously able to sustain.
On my older laptop with only 802.11b capability, by itself, I repeated the same experiment and saw a rate of 425Kbytes/sec according to sftp, or 3.7Mbits/sec according to iptraf.
With both computers downloading simultaneously, the wireless net naturally downshifted to the lower speed. When I turned off the download on the slower computer, the speed quickly increased for the faster laptop.
The aforementioned data rates have been sustained for at least 15 minutes, where before, I couldn't do this for even 1-2 minutes.
I think I can declare victory. Thanks for the help!
Happy New Year!
Andy
- -- Andy Stewart (KB1OIQ) Founder: Worcester Linux Users' Group Founder: Chelmsford Linux Meetup Group President: PART of Westford, MA (WB1GOF) -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org
iD8DBQFLPDHrOjiraCaOTOoRAhGOAKDGbFyuNUwoNtBZyP8pqEA9yUUFIwCgmP4n m+svFxGvxXhKue9emJlWjG8= =/Mkl -----END PGP SIGNATURE----- _______________________________________________ Wlug mailing list Wlug@mail.wlug.org http://mail.wlug.org/mailman/listinfo/wlug
On 12/31/2009 3:47 PM, Jorden Mauro wrote:
I've never been able to find a channel free from microwave oven interference, sadly. I'm convinced my ancient microwave puts out a wide spectrum and leaks plenty.
Between cordless telephones, microwaves, bluetooth, and neighbors, the only reliable channel I've found is to ditch 2.4 altogether and use something in the 802.11a band. -- Frank Sweetser fs at wpi.edu | For every problem, there is a solution that WPI Senior Network Engineer | is simple, elegant, and wrong. - HL Mencken GPG fingerprint = 6174 1257 129E 0D21 D8D4 E8A3 8E39 29E3 E2E8 8CEC
On Thu, Dec 31, 2009 at 8:56 PM, Frank Sweetser <fs@wpi.edu> wrote:
On 12/31/2009 3:47 PM, Jorden Mauro wrote:
I've never been able to find a channel free from microwave oven interference, sadly. I'm convinced my ancient microwave puts out a wide spectrum and leaks plenty.
Between cordless telephones, microwaves, bluetooth, and neighbors, the only reliable channel I've found is to ditch 2.4 altogether and use something in the 802.11a band.
That's quite a bandwidth sacrifice if you've designed your network for n.
-- Frank Sweetser fs at wpi.edu | For every problem, there is a solution that WPI Senior Network Engineer | is simple, elegant, and wrong. - HL Mencken GPG fingerprint = 6174 1257 129E 0D21 D8D4 E8A3 8E39 29E3 E2E8 8CEC
On 12/31/2009 3:58 PM, Jorden Mauro wrote:
On Thu, Dec 31, 2009 at 8:56 PM, Frank Sweetser<fs@wpi.edu> wrote:
On 12/31/2009 3:47 PM, Jorden Mauro wrote:
I've never been able to find a channel free from microwave oven interference, sadly. I'm convinced my ancient microwave puts out a wide spectrum and leaks plenty.
Between cordless telephones, microwaves, bluetooth, and neighbors, the only reliable channel I've found is to ditch 2.4 altogether and use something in the 802.11a band.
That's quite a bandwidth sacrifice if you've designed your network for n.
Huh? 802.11n, unlike the a/b/g operating modes, isn't tied to one particular band - it'll happily operate in either 2.4Ghz or 5Ghz. Some particular models only support one band or the other, but that's an implementation limitation, not one in the spec. In fact, since the 5Ghz band has 19 non-overlapping channels, as opposed to 3 in 2.4Ghz, you're far more likely to have two adjacent clear channels available, giving you the option of running a 40Mhz wide channel instead of just 20Mhz, and therefore twice the bandwidth. -- Frank Sweetser fs at wpi.edu | For every problem, there is a solution that WPI Senior Network Engineer | is simple, elegant, and wrong. - HL Mencken GPG fingerprint = 6174 1257 129E 0D21 D8D4 E8A3 8E39 29E3 E2E8 8CEC
On Dec 31, 2009, at 5:21 PM, Frank Sweetser <fs@WPI.EDU> wrote:
On 12/31/2009 3:58 PM, Jorden Mauro wrote:
On Thu, Dec 31, 2009 at 8:56 PM, Frank Sweetser<fs@wpi.edu> wrote:
On 12/31/2009 3:47 PM, Jorden Mauro wrote:
I've never been able to find a channel free from microwave oven interference, sadly. I'm convinced my ancient microwave puts out a wide spectrum and leaks plenty.
Between cordless telephones, microwaves, bluetooth, and neighbors, the only reliable channel I've found is to ditch 2.4 altogether and use something in the 802.11a band.
That's quite a bandwidth sacrifice if you've designed your network for n.
Huh? 802.11n, unlike the a/b/g operating modes, isn't tied to one particular band - it'll happily operate in either 2.4Ghz or 5Ghz. Some particular models only support one band or the other, but that's an implementation limitation, not one in the spec.
In fact, since the 5Ghz band has 19 non-overlapping channels, as opposed to 3 in 2.4Ghz, you're far more likely to have two adjacent clear channels available, giving you the option of running a 40Mhz wide channel instead of just 20Mhz, and therefore twice the bandwidth.
I had no idea. I'll have to tinker with my router.
-- Frank Sweetser fs at wpi.edu | For every problem, there is a solution that WPI Senior Network Engineer | is simple, elegant, and wrong. - HL Mencken GPG fingerprint = 6174 1257 129E 0D21 D8D4 E8A3 8E39 29E3 E2E8 8CEC
On 12/31/2009 5:37 PM, Jorden Mauro wrote:
In fact, since the 5Ghz band has 19 non-overlapping channels, as opposed to 3 in 2.4Ghz, you're far more likely to have two adjacent clear channels available, giving you the option of running a 40Mhz wide channel instead of just 20Mhz, and therefore twice the bandwidth.
I had no idea. I'll have to tinker with my router.
I should also mention that 40Mhz channels are an optional feature in the 11n spec, so not all hardware will implement it. In other words, don't be surprised if you don't see it on SOHO class hardware. -- Frank Sweetser fs at wpi.edu | For every problem, there is a solution that WPI Senior Network Engineer | is simple, elegant, and wrong. - HL Mencken GPG fingerprint = 6174 1257 129E 0D21 D8D4 E8A3 8E39 29E3 E2E8 8CEC
participants (5)
-
Andy Stewart -
E Johnson -
Frank Sweetser -
John Stoffel -
Jorden Mauro