Why does a new router slow down my network?

[TheInternal]

I have two machines running Windows 7 hooked up to my 1 gb switch. The switch is connected to my new router (which has WEP passworded N draft Wi-Fi wireless).

What I don't understand is why Windows 7 is transferring data from one computer to the other so slowly, around 10 MB/sec at best.

Is my router killing the benefit of my 1 gb switch?

Is this a limitation of windows 7?

I'm guessing I'm overlooking something simple/obvious, so any input is welcome.

 

[drebo]

You're overlooking the fact that with a consumer grade OS and consumer grade equipment, that's probably the best you're going to get.

You can try enabling features like jumbo frames, etc, and using a protocol with less overhead, such as FTP. You might get better results that way.

 

[pukemon]

Although you didn't explicitly mention it, but I think we're assuming that your router does have a built-in gigabit switch, right?

 

[JackMDS]

Or if the switch is separate from the Router give the computers temp static IPs and try it without a connection to the Router.

Mediocre Giga switch with No special setting in the computers should yield about 25 to 35 MB/sec.

Good consumer switch, with Optimized TCP/IP can go as high as this, http://www.ezlan.net/vista/Giga-Optimized

The NICs in the above example are simple onboard Marvel.

The switch is, http://www.newegg.com/Product/...x?Item=N82E16833156251

Cables are regular Cat5e from Monoprice.

 

[Madwand1]

Originally posted by: TheInternal
I have two machines running Windows 7 hooked up to my 1 gb switch. The switch is connected to my new router (which has WEP passworded N draft Wi-Fi wireless).

This has nothing to do with your wired transfer speed, but you should avoid WEP if possible -- it has a severe performance penalty and is not actually secure.

Originally posted by: TheInternal
What I don't understand is why Windows 7 is transferring data from one computer to the other so slowly, around 10 MB/sec at best.

Sounds like one of your NICs might not be negotiating gigabit properly. Does your switch have color coding on the connections to indicate the link speed? Did you confirm that both ends are connecting at gigabit speed?

If you are connecting at gigabit speed, the next question is whether the problem is at the network level or the file system / protocol level. For this, you can use iperf version 1.7 as follows:

server: iperf -s
client: iperf -c server -l 64k -t 15 -i 3 -r

where server is the name or IP of the remote computer running iperf -s.

You might need to enable the connections through firewalls to get this to work.

As Jack said, you should be easily hitting 25 MB/s on very large files (small files could be slower). With W7, it could be much faster, but there are no guarantees and multiple possible points of failure/bottleneck. So no, W7 should not be a bottleneck, but as it's new, you could be running into a new issue, e.g. rushed NIC drivers which aren't properly tuned for performance. This sort of problem could show up in the iperf test, and be addressed via a driver update from the NIC chipset manufacturer.

 

[tranceport]

Originally posted by: Madwand1

Originally posted by: TheInternal
What I don't understand is why Windows 7 is transferring data from one computer to the other so slowly, around 10 MB/sec at best.

Sounds like one of your NICs might not be negotiating gigabit properly. Does your switch have color coding on the connections to indicate the link speed? Did you confirm that both ends are connecting at gigabit speed?

If you are connecting at gigabit speed, the next question is whether the problem is at the network level or the file system / protocol level. For this, you can use iperf version 1.7 as follows:

server: iperf -s
client: iperf -c server -l 64k -t 15 -i 3 -r

where server is the name or IP of the remote computer running iperf -s.

You might need to enable the connections through firewalls to get this to work.

As Jack said, you should be easily hitting 25 MB/s on very large files (small files could be slower). With W7, it could be much faster, but there are no guarantees and multiple possible points of failure/bottleneck. So no, W7 should not be a bottleneck, but as it's new, you could be running into a new issue, e.g. rushed NIC drivers which aren't properly tuned for performance. This sort of problem could show up in the iperf test, and be addressed via a driver update from the NIC chipset manufacturer.

This would be one of my first troubleshooting steps.