upload speed >>> download speed

[Teknic]

So we switched the ISP to Comcast and in doing so changed the router as well. The past two days my laptop and desktop connected to the internet with a speed of 13 Mb/s and 2 Mb/s upload speed. However, another desktop, directly connected to the router, connected with a speed of 1.00 Mb/s and 2 Mb/s upload.

Today, all computers are connected to the internet with a download speed of about 0.45 Mb/s and an upload speed of 2 Mb/s. I really think the router is at fault, since yesterday it was only the computer directly connected to the router that was affected.

Anybody have any ideas on what settings I can change? I have tried google/bing to no avail.

 

[Mr. Pedantic]

Could just be because everyone else on the cable is downloading like crazy so everyone's speed is throttled to make sure everyone gets some. Whereas not everyone hosts an ftp server through their desktop.

 

[Teknic]

Actually I was mistaken my desktop still gets fast download speeds. The speed test was from my laptop previously. I still don't understand why my laptop internet speed changed from fast to slow, I didn't change any settings!

This is from my desktop.



All the other computers are currently off right now except the ones being used (by me). My desktop and laptop are both connected to the network wirelessly in the same room with the same OS. However, the desktop physically connected with a wire and my laptop are both now super slow. Also, no one is downloading or hosting an FTP server.

 

[TSDible]

How are you connecting the laptop?

Wireless? Wired?

Could it be a communication issue between the new router and your laptop?

 

[bobdole369]

Somethings borked the stack. Start physical and move up the model.
LAN cable, Drivers, OS, browser.

 

[Texashiker]

Check out speedguide.net, they have some tools to check your tcp/ip settings - like the receive window buffer, and MTU size.

Speedguide.net - Left column - Broadband - Broadband tools - SG TCP/IP Analyzer

From there they have some patches to reset your tcp/ip stack settings back to default, just in case you installed any programs that are "supposed" to speed up your Internets.

 

[spidey07]

Sounds like a duplex mismatch. Make sure all NICs and anything they attach to is set to autonegotiate.

 

[Teknic]

How are you connecting the laptop?

Wireless? Wired?

Could it be a communication issue between the new router and your laptop?

My laptop and desktop are connected via wireless. There's another desktop connected to the router directly with wire.

Somethings borked the stack. Start physical and move up the model.
LAN cable, Drivers, OS, browser.

All 3 computers use a fairly new version of Windows. Speed tested with IE, Firefox, Chrome, all about the same. I think the cable is fine though.

As for drivers, the firmware is up to date using the recommended firmware, and I looked it up and apparently it's some open source drivers? DD-WRT.

Check out speedguide.net, they have some tools to check your tcp/ip settings - like the receive window buffer, and MTU size.

Speedguide.net - Left column - Broadband - Broadband tools - SG TCP/IP Analyzer

From there they have some patches to reset your tcp/ip stack settings back to default, just in case you installed any programs that are "supposed" to speed up your Internets.

Thank you, will check on this at home.

 

[Teknic]

Sounds like a duplex mismatch. Make sure all NICs and anything they attach to is set to autonegotiate.

I have no idea what you just said but I will google this when I get home.

 

[Texashiker]

Thank you, will check on this at home.

Your welcome.

I used to work as a cable modem tech for an ISP in Houston, Texas. Sometimes when a customers cable modem would get hooked up, they would get exactly 56kb download speeds, and not a kb faster. Their upload speed was normal, but their download was dialup speed.

About 99% of those customers had installed some kind of software that was "supposed" to speed up their dial up service.

Once the internet accelerator software was removed, and the tcp/ip default patch from speedguide was applied, the customers download speed would go to where it was supposed to be, which was in the 2 - 5mbs range.

So when I see a customers upload / download speeds mix matched, that tells me that something has changed your tcp/ip settings. It usually has to do with the receive window buffer size, or the MTU size.

Another thing that can affect speed is noise on the line. This is outside radio signal interference that has gotten into the cable line. If you have poor quality cable lines in your house, or where a rodent has chewed a hole in the cable line, this can let noise into the line.

If the poor speed does not get better, call your ISP and ask them to check the signal to noise ratio of your cable modem. Just about all docsis 2.0 and better cable modems should have a built in signal meter and signal to nose ratio meter. Your isp help desk should be able to pull up their cable modem tools and check your modem without having to send a tech out.

 

[Teknic]

...
Once the internet accelerator software was removed, and the tcp/ip default patch from speedguide was applied, the customers download speed would go to where it was supposed to be, which was in the 2 - 5mbs range.

So when I see a customers upload / download speeds mix matched, that tells me that something has changed your tcp/ip settings. It usually has to do with the receive window buffer size, or the MTU size.
...

Would doing this help even if I know that there was no internet accelerator installed? I definitely would not have installed such accelerator software, but I will try out the TCP/IP analyzer program later tonight.

Another thing that can affect speed is noise on the line. This is outside radio signal interference that has gotten into the cable line. If you have poor quality cable lines in your house, or where a rodent has chewed a hole in the cable line, this can let noise into the line.

If the poor speed does not get better, call your ISP and ask them to check the signal to noise ratio of your cable modem. Just about all docsis 2.0 and better cable modems should have a built in signal meter and signal to nose ratio meter. Your isp help desk should be able to pull up their cable modem tools and check your modem without having to send a tech out.

I don't think it's noise on the line, because on one computer I can get 0.35Mb/s - 0.5Mb/s and the other will get 12-14 Mb/s testing one right after the other. Upload speeds for all computers are 2 Mb/s though.

 

[Texashiker]

Would doing this help even if I know that there was no internet accelerator installed? I definitely would not have installed such accelerator software, but I will try out the TCP/IP analyzer program later tonight.

Do you have a way to bypass the router and connect each computer to the modem? If so, connect each system to the modem and run it through the TCP/IP analyzer.

From there, take a look at the SG TCP Optimizer - its the first download on this page speedguide.net/downloads.php

Using that program you can tweak settings like MTU, RWIN, QoS and ToS/Diffserv prioritization.

If your really brave, there are some tcp/ip patches on that same page.

 

[Teknic]

Tried working on it for two hours today and tried all the advice I found here. After coming no closer and understanding even less, I gave up.

I ended up finding the last router that I used in a box somewhere, plugged it in and it works fine now! (so far, tested on the computers that kept giving me trouble)



So...sorry I didn't have an answer to exactly why the router acted as it did, but thanks for all your help people! :thumbsup: