dotan_ak@yahoo.com hath wroth:

Ever consider the possibilty that you can't figure it out because you
have a CCNA? Just a thought.

>I have a Cable modem at home with download speeds of 13 - 15Mb/s. I
>love it!

Cease bragging. I've only got 1.5Mbits/sec.

>Unfortunately, I only measure those speeds on my wired
>computers. The wireless ones (I tried 2 laptops using 2 different
>PCMCIA cards) only get around 6.5-7 Mb/s when downloading from the
>Internet.

It should be much faster than that. I just ran a quicky wireless
benchmark test using IPerf just yielded 18Mbits/sec TCP thruput on my
home WRT54GSv4. It's a bit slow because the neighbors are doing
something on my connection via wireless. See:
<http://wireless.wikia.com/wiki/Wi-Fi#Performance_and_Speed>
for maximum theoretical speeds.

>NOTE: when transferring a file from my wired computer to the wireless
>one, I did get around 15Mb/s. That's slow but it proves that the
>wireless computer can receive more than 7Mb/s.

It would be best if you take the internet out of your benchmarks. If
you have a wired desktop (not wireless) available, setup IPerf server
on it and do your wireless benchmarking locally. That will also take
the router and cable modem out of the picture.
<http://dast.nlanr.net/Projects/Iperf/>

>I am using my new Linksys WRT54GS.

What hardware version (look on serial number tag)?
What firmware version (see status page)?

>Both laptops are P4, 512MB RAM,
>Win XP SP2.

Cool. You have 2 machines. Do the IPerf server thing with one of
them in wired configuration.

On the wireless laptop, at what wireless speed are you connecting to
the WRT54GS? Your thruput should be about half the connection speed.

>Here is what I tried to eliminate the obvious:

From Sherlock Holmes: When we have eliminated the obvious, the
apparent, and those items unworthy of being checked, what remains,
however improbable, is what we have overlooked and have screwed up.

Do you have simultaneous wired and wireless connections running on the
test laptop? The "route print" command will show the current router
table. Look at the "metric" column to see which route has preference.
Most XP laptops will autoswitch between wireless and wired but I've
seen a few utilities that screw things up.

I'll admit that you did a good job of trying to isolate the problem.
The trouble is that you're apparently doing everything with an
internet benchmarking tool. That's fine for later, but makes it
difficult to clearly identify the culprit. Try it without the
internet first.

>Is Wireless Internet severely limited? Am I missing something?

No, not that severely.

1. Connect BOTH laptops to the WRT54GS via CAT5 cables. Unplug the
cable modem to keep it out of the way. Run IPerf benchmark in TCP
mode (with default parameters). At 100baseT-FDX, you should get about
80Mbits/sec or more. Basically, we're testing the IPerf software and
computers with this test.

On the server:
IPerf -s
On the client:
IPerf -r -c ip_address_of_server
The -r will do a non-simultaneous bi-directional test in case the
problem is asymmetrical.

If the numbers here are unusually low, check:
netstat -s | more
for any IP and TCP layer errors. Any errors are probably at the MAC
layer, but you'll need to fish those out with the ethernet card
diagnostics.

2. Now, replace one of the CAT5 cable with a wireless connection and
run the same IPerf benchmarks again. Note the wireless connection
speed. You should get about half the connection speed.

Let us know what you get here and we'll blunder onward depending on
the wireless benchmark results.

--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558