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n8x · Jun 11, 2003, 01:20 AM

I recently switched from cable to dsl, and the first thing i noticed was that my download speeds are reduced to next to nothing while using filesharing apps.

Even if these apps are downloading and uploading at speeds low as 5kbps, i am completely unable to even surf the web. However, when they aren't on i get very nice download speeds (and the bandwidthplace.com speed test clocks my connection at the 1.4mbps Verison advertises).

I've tried throttled and carrafix but they don't seem to have any effect.. has anyone else ever had similar problems? Does DSL just suck horribly?

ghporter · Jun 11, 2003, 10:44 PM

DSL does not suck-I'm enjoying it right now. Your DSL is just not as fast as your old cable, which was probably better at taking up the slack caused by your apps. What modem did Verizon provide you with, and are you using a router? Both could have an affect on the efficiency of your connection.

File sharing apps are notorious for doing things the way they want, not necessarily the right way, including changing network settings. Most are built with the assumption that you'll be using a dedicated bandwidth, not an asymetrical DSL connection. Which apps are you encountering problems with.

n8x · Jun 12, 2003, 09:12 PM

The modem is a Westell Wirespeed, and the apps seem to be the ones that make large amounts of connections like MLDonkey.. not using a router though.

ghporter · Jun 12, 2003, 10:21 PM

That's a good modem-I happen to be using a Wirespeed 516 at this moment. I'd suspect that it's a combination of the MTU setting and the way MLDonkey uses the network.

The MTU for DSL should be 1492-not 1500 as was the case with your cable connection. You can set it manually by going to the terminal and typing:

% sudo ifconfig en1 mtu 1492

Or you could look at this page for more detailed instructions.

This is incredibly important; it determines the size of the packets sent through your modem. If your computer tries to send a packet that's too large, it gets fragmented and can cut your speed drastically. That sounds like what's happening: MLDonkey is trying to send large packets, and it's fragmenting like crazy.

P.S. Apps like MLDonkey are being targeted by virus writers as the distribution mechanism for their crap. Be very careful and make sure you're running a good, updated virus checker.

n8x · Jun 13, 2003, 04:53 PM

Woohoo, that fixed it, thanks! Apple really should put a setting for that somewhere..

And yes, I do have virus checking. It hasn't found anything yet, but security is always good.

ghporter · Jun 13, 2003, 10:04 PM

Woohoo back at you! Glad I could help. As I understand it, if you burrow down far enough in System Preferences to do just about anything with you networking-except tweak your MTU. It just has to be done from Terminal. Sure, it's a geekey kind of adjustment, but you don't have to be a geek to switch from cable to DSL, or vice versa. Come on guys! Make things easier, like they're supposed to be on a Mac!

Again, glad to help.