On Mon, 2 Apr 2007 13:03:10 -0500, "Jim" <jcgc50@cox.net> wrote:
>Jeff, sorry, I sent this response to you rather than the group. Will try
>again.
Not a problem. I've been ignoring my email for weeks. It's amazing
how much more spare time I now have.
>I am using a laptop which happens to be located in the same room. Signal
>strength shows excellent at 54 mbps.
Many unspecified laptops and random wireless cards report 54Mbits/sec
on initial connection and when there is no traffic. Try downloading
something and see if the wireless connection speed changes.
Also, I kinda perfer to have the numbers instead of generalizations
such as "excellent". What number did you get for signal strength (in
-dBm) and what does it show for SNR (signal to noise ratio). Get
these numbers while moving data or immediately after a download. It's
possible to have excellent signal strength, but rotten SNR due to
interference.
>I have been using this setup for over a
>year now and it has always been this way and I have not figured it out.
I would have guessed interference but there are few forms of
interference that last for "over a year". Also, if it's in the same
room, the likelyhood of substantial interference having an effect is
considerably less. Obviously, it's also not signal strength.
>SSID
>broadcasting is turned off and I have MAC filtering.
Both are a lousy idea. SSID hiding just means that your neighbors
will end up on your chosen channel. MAC filtering has it's place but
is easily spoofed. However, you did mention that you're using WPA
encryption, which is really your main and only form of security.
Hopefully, you've selected a long and difficult to brute force guess
pass phrase.
>I have changed those
>settings and found no difference in performance.
Question: Was the wireless performance good at any time in the past
year?
>If it didn't involve too much work I would arrange to run this wired most of
>the time. As it is I am only occasionally downloading large files.
>
>WRT54G v 3.1 Firmware 4.20.7. I have upgraded the firmware once and don't
>know if there is an update but that did nothing either.
The current version of the firmware is 4.21.1 issued Jan 20, 2007. You
might want to try it.
>Does this information provide any ideas.
Not really, You've adequately described the WRT54G end of the link.
However, the other end is still a mystery. It takes two to tango and
the problem could easily be in the wireless part of the laptop. Any
particular maker and model number? Any particular wireless device?
Extra points for finding the firmware version.
Since you get adequate speed with a directly wired ethernet
connection, it's probably not a worm or virus hogging CPU cycles in
the laptop. It might be some configuration issue involving the
wireless device, but that's very rare (unless you've been tinkering in
the wireless devices properties). It might be traffic from a neighbor
leaching off your wireless, but that would not be continuous for the
last year.
One way to really screw things up is to have two systems using the
same SSID. For a quick test, change your SSID to something else
that's sufficiently obscure not to be duplicated. You might also try
different channels (1, 6, or 11) and see if that helps. It probably
won't but it's easy enough to try. You only need to change the
channel in the WRT54G as the client radios will follow the change.
The way I would troubleshoot this one is by substitution. Find a
different known working laptop and try it to see if it has the same
problem. If that results in the same lousy wireless performance, then
there's either interference of some unknown type, or the WRT54G has a
problem.
At some point, you might want to scribble down all the WRT54G
settings, update the firmware, reset the router to defaults, and put
them back manually (not from the saved image file). Just put back
enough setting to be able to use the system and never mind the
security details and tweaks. Basically, try it with the default
settings. If that works, then one of the setting broke something. I
had one user do this only to find that someone had inadvertently set
the wireless to 802.11b only, which limited the wireless speed to
about 5Mbits/sec. Setting such as CTS/RTS flow, 802.11b
compatibility, fragmentation threshold, etc will cause slowdowns.
The next step is to replace the router with a different model. It
might be possible to borrow one. If that works as expected, then
there's something broken in the router. It's probably too late for a
warranty claim.
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
jeffl@comix.santa-cruz.ca.us
#
http://802.11junk.com jeffl@cruzio.com
#
http://www.LearnByDestroying.com AE6KS
Wireless router slows connection 
Linear Mode
