Network Speed Settings

[Shepmaster]

Hey All,

I live in a mixed-platform environment in a dorm. Most of the computers are x86 based boxes. Each dorm has a switch in the bottom, which I suppose uplinks into the rest of the network, eventually making its way out. My problem is that for some reason, my connection is slow. Technically, we are told we are on a 10 Mb network inside each dorm, and then a 100 Mb on the campus. However, my speeds are normally on the order of 1 Mb. Last semester, I achieved upwards of 7 Mb. Over Christmas break, I got bored and reformatted and installed, and now my connection is, as I said slow. The only bright concept I had is to set the duplexity manually. It defaults to half-duplex, but I know everyone else is using full-duplex. I have a feeling that the switch is configured that way, for older computers. I tried using ifconfig, but all I get get is an arcane error. Any ideas on how best to manually set my connection speed?

-Shepmaster

[mksmith]

Hello:

In general, you should leave your connection on auto-sense because that is likely what the switch is set to. If you hard set your duplex setting the other side will have to be likewise hard set. If not, you will receive duplex mismatch problems that will seriously curtail your connection.

As far as your usage, you may want to see if others on your particular network segment are experiencing similar issues. It may be that you are just on a seriously congested link.

Mike

[Shepmaster]

Originally posted by mksmith
Hello:

In general, you should leave your connection on auto-sense because that is likely what the switch is set to. If you hard set your duplex setting the other side will have to be likewise hard set. If not, you will receive duplex mismatch problems that will seriously curtail your connection.

Well, my side is set to autodetect, but as far as I know, so if everyone else's. They default to half-duplex as well, and manually setting by setting a setting in their registry. Obviously, I cannot solve it in the same fashion, but I was hoping for something similar.

As far as your usage, you may want to see if others on your particular network segment are experiencing similar issues. It may be that you are just on a seriously congested link.

Mike

The switch for our dorm serves all 60-odd people in the dorm. These are the people that I have seen to care enough to change their settings. I have achieved the full-duplex before, but it was intermittent. Thanks for all your advice

-Shepmaster

[Dr-NiKoN]

Does your machine have gigabit ethernet?

"Well, my side is set to autodetect, but as far as I know, so if everyone else's."

The problem might be(if you have gigabit ethernet), that the switch is having problems negoitiating a decent speed for you.
This is a known shortcoming with most of the 10/100b switches. And, since there isn't really any tool for OS X to 'set' the speed to either 10 or 100, you get stranded with crappy speeds. I don't have the details of your problem, but this might be the problem.

If you have gigabit ethernet, you might want to find out what kind of device you are connecting too, and giving the manufactorer a shout-out. All that is needed is a firmware upgrade on that device.

nikon

[jetucker]

You should leave your NIC on "auto-sense" or "auto-negotiate" (whatever the settings are called on your particular device) unless you have control of both devices at the ends of the wire or unless you know for a fact that you should be set one way or the other because the person in control of the other equipment told you so.

You might get lucky and have it work, but it's unlikely to work any better than with auto.

Trouble comes if one side is set to "Full Duplex" and the other is set to "Half Duplex". The explanation is straightforward but lengthy, so I'll skip it.

Speeds, on the other hand, are either going to work or not. Ethernet is only going to work at 10Mbps, 100Mbps or 1000Mbps. Both ends HAVE to be the same (or auto) and there are NO in-between speeds to be negotiated. Doesn't work that way....

Your throughput problems could have many causes, not the least of which might be sharing a single 10Mbps connection with your entire floor or even a 100Mbps connection with the entire building. Then there's the router and switch infrastructure elsewhere on campus.

It's a tough problem, but unlikely one you can control on you NIC parameters.

jet