Slow speeds

Jolsa

Hi,
Does anyone here know about wireless networks? Am connected to our one in the flat (Airport extreme) on my PC.

On a 4meg connection, but my download speeds level out at 100 KB/Sec, whereas my mate using his Apple Powerbook *or* Sony Vaio laptop is reaching 350-400 KB/Sec on the same downloads at the same time.

Obviously it isnt some mac/pc thing due to the Sony Vaio.

Could it be my wireless card? I'm using a D-Link DWL-510 which provides transmission speeds at up to 11 Mbps, i.e. not one of the newer, better cards which allows speeds of up to 54 Mbps.

If anyone has any knowledge on this I'd be very pleased to hear it!

Toxteth_OGrady

Your wireless card is less likely to be a factor as it's theoretically almost 3 time faster than your Internet connection so it shouldn't be the bottleneck.

If you and your mate are doing exactly the same download at exactly the same time, I'm not surprised one of you is taking a performance hit. Lots of variables could cause this starting with congestion and throttling on the output fileserver.

If you do exactly the same download again, but this time without your mate competing for the same bandwidth, what result do you get?.

If you are consistently getting worse results, even when you are not competing with each other for bandwidth then the first thing I would look at would be your MTU and RWIN settings.

:cool:

TOG

Jolsa

Thanks for your response. We're downloading the same file 30 or so seconds apart, never at the same time. I just wanted to see our differing speeds, which they do greatly!

Would you be able to explain a bit more about the MTU and RWIN settings please?
You describe them as though they could be limiting my download speeds?

What I didnt mention before, is that I have previously managed the much higher download speeds on the same file - 350 KB/Sec ish (MSN messenger download), however this was weeks ago, and I haven't been adjusting any settings since - not deliberately anyway :-)

Toxteth_OGrady

There are plenty of online speedtesters you can use to test your connection.

One of the most commonly used can be found at https://www.adslguide.org.

However for a more accurate test it's better if you can run for a sustained period with a large file test download.

Try this one here.

Bost back with the results of both of these speedtests. If it's still a problem we can have a look at tweaking your MTU and RWIN.

One way of bowling out whether it's a problem with your wireless card, would be to set-up an ad-hoc wireless connection directly between your mate's laptop and your PC. Then transfer a large file, first one way and then the other, time it and calculate the actual speed you are getting with your wireless card.

:cool:

TOG

Jolsa

Thanks TOG,

For the first speed test I got the following(!):

Downstream 152 Kbps (19.0 KB/sec) 164 Kbps (inc. overheads)
Upstream 14 Kbps (1.8 KB/sec) 15 Kbps (inc. overheads)

On the big file test, my download speed levelled at around 52 Kbps.

I've also tried doing the ZDNet speed test several times before, and always get very poor results (as if I wasn't even on a 1 meg connection) from that.

I've googled a bit on the MTU and RWIN settings, and followed the changes using Dr TCP as shown here:
http://www.tiscali.co.uk/help/broadband/connectionoptimisationii.html

However after a reboot, there is no change to the download speeds.

Is there anything else I can try regarding the MTU and RWIN settings? Different values?

Thanks.

Toxteth_OGrady

Those results are pitiful :eek:

No amount of MTU or RWIN tweaking is gonna sort that out.

However, good find on Dr. TCP, that's one of the tweakers I recommend.

If your mate is still getting good speeds and you're using the same connection, that rules out any upstream ISP problems (unless you're suffering from FUP throttling on your IP address due to previous leeching).

So as you rightly deduced earlier, next likely candidste is your wireless card. Can you do the ad-hoc 1-to-1 test?

:cool:

TOG

Jolsa

Hmm, had problems before trying to sort out our computers seeing eachother on the network. Not sure if thats a Mac/windows thing, but I'll read up on it, and attempt to do the procedure you mentioned.

Thanks loads for your replies TOG, hopefully I'll have something to post back tomorrow.

Toxteth_OGrady

no worries mate. That's what this is for

:cool:

TOG

Jolsa

It's quite impersonal though, I prefer to write my thanks ;-) I'll click it also for the hell of it though :-)

Jolsa

A 4 meg line does not mean you download at 4MB/Sec. I think a download rate of around 400KB/Sec is in par with a 4 meg line, so my flatmate is certainly getting a decent download speed.

We have our wireless networked secured so no worries about other people using it. Also I've run Spybot on my machine and have AntiVirus up to date.

I'll attempt TOG's latest suggestion, other than that I guess a better wireless card might be in order.

albertross_2

OK, sorry read the B as a b..

If you are getting 400 Kilobytes (not Kilobits) per second that is fine..

If you are getting 400 Kilobits/s that is still slow for that speed link, if it consistent all day, and that is what it reported from the adslguide test.