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ajkidle
2010-04-26, 17:49
What I originally believed to be Cat-5 running through my house has turned out to be Cat-3. I had hoped to repurpose the phone system (the Cat-3 wiring) to provide ethernet throughout the house. Are my hopes dashed? Wikipedia says Cat-3 is for 10Mbps, doesn't sound like a very good idea to plug this into a gigabit router -- correct?

JJZolx
2010-04-26, 18:16
What I originally believed to be Cat-5 running through my house has turned out to be Cat-3. I had hoped to repurpose the phone system (the Cat-3 wiring) to provide ethernet throughout the house. Are my hopes dashed? Wikipedia says Cat-3 is for 10Mbps, doesn't sound like a very good idea to plug this into a gigabit router -- correct?

Well, you can expect it to work at 10 Mbps, maybe 100 Mbps if you're really really lucky. It's not going to hurt your switch. A 10 Mbps run is more than fast enough to stream 16/44.1 audio uncompressed and it may turn out to be more reliable than a poor wireless connection.

Soulkeeper
2010-04-27, 00:18
That's interesting.

http://en.wikipedia.org/wiki/Category_3_cable

In theory you can get reliable 100 Mbps from Cat3, but that probably requires some special hardware in each end of the cable.

http://en.wikipedia.org/wiki/100BASE-T4#100BASE-T4

SuperQ
2010-04-27, 09:21
I have had situations where we had to run networking over cat3 due to very old buildings. Most modern 100mbps PHYs are good enough that it should work reasonably well. Gigabit on the other hand is not going to work well. It might get a link but you will get mostly packet loss. You will get some packet loss, but nothing TCP can't deal with, and it won't be an issue for the squeezebox.

ajkidle
2010-04-27, 18:51
So the router will throttle the speed automatically based on quality of the connection?

agillis
2010-04-27, 21:18
So the router will throttle the speed automatically based on quality of the connection?

It might but your audio quality will definably suffer. Expect dropouts as your router tries to make everything work.

Your better off going with wireless then trying to run Gig over Cat3.

Mark Miksis
2010-04-27, 21:35
Your better off going with wireless then trying to run Gig over Cat3.

In this case, there's no point in trying to use GE anyway since none of the SB products support it. You may get away with 10/100 especially if your runs are much shorter than the 90m allowed for CAT5.

Soulkeeper
2010-04-28, 07:11
True. Cable length is an important factor. I used to make my CAT5 cables terribly terribly wrong, but didn't even notice until I once mounted one in a mechanical workshop (probably full of noise) and couldn't make it work. :P

That's when I learned you have to take the twisted pairs into account. And I had been making cables 10-20 meters long, never even noticing that anything was wrong.

Needless to say, I snuck back and re-terminated quite a few cables, hoping that nobody would ask me what I was doing.