Is it possible to have 2 ethernet connections over 1 cable?

3

Can I have one 4-twisted-pair cable (cat5) and split them into 2 ethernet ports? I know ethernet only needs 4 wires so that wouldn't be the problem but will it interfer with eachother or would that be no issue?

Ravenix

Posted 2016-12-20T08:51:23.557

Reputation: 253

Question was closed 2016-12-20T10:32:51.403

1

You shouldn't actually open up the cable and just take some of the wires for one computer, and some of them for the other. splitters are available but your router/modem will need to have two available ports (one for each of the connected devices), so all it does is 'combine' the two cables into one for most of the way. I'd recommend getting a switch to do your splitting so it can retain your full speed and you're not doing some hacky solution.

– cascer1 – 2016-12-20T08:56:01.343

Sorry @cascer1 - I didn't mean to steal your comment. I actually posted my answer before I read your post. – Tetsujin – 2016-12-20T09:03:18.437

@Tetsujin Don't worry about it :) – cascer1 – 2016-12-20T09:03:49.227

"It will be used to connect multiple pc's to the same network" -- Then you're asking an XY question. All you need is an Ethernet switch. – sawdust – 2016-12-20T19:58:40.200

So, this question is a duplicate of a duplicate? – isanae – 2016-12-21T00:28:44.603

Answers

12

Yes, it will work, though it will be limited to 100 Base-T speeds.

However...
For the price of two splitters & the extra cables you'd then need at each end, you could probably get a cheap ethernet switch & keep your 1000 Base-T speeds.

Tetsujin

Posted 2016-12-20T08:51:23.557

Reputation: 22 456

2There's a reasonable chance it'll drop down to 10 Base-T speeds. Totally worth the ethernet switch IMO. – Journeyman Geek – 2016-12-20T10:33:29.140

2

You could use VLANs and give each "cable" a VLAN number, that way computers set to a particular VLAN will only see packets tagged with that VLAN number, using a standard (unmanaged) switch to split the cable into multiple ports.

You could also use a managed (business-grade) switch that could handle the VLANs by itself and assign each VLAN to a particular port, that way the computers don't need any configuration and it's a bit more secure as the machines don't receive the packets of the adjacent VLAN (where as in the first situation the packets still reach both machines, so if any are evil they could still listen into the adjacent VLAN's traffic).

André Borie

Posted 2016-12-20T08:51:23.557

Reputation: 974

1

Yes, this will work fine if you use two proper fast Ethernet splitters, one on each end. Speed will be limited to 100Mbps -- gigabit Ethernet won't work as it uses all four pairs.

David Schwartz

Posted 2016-12-20T08:51:23.557

Reputation: 58 310

1

You could also use a VLAN, depending on the reason behind needing two Ethernet connections.

Hampkade

Posted 2016-12-20T08:51:23.557

Reputation: 41

It will be used to connect multiple pc's to the same network. Not sure how a VLAN has to do with this? – Ravenix – 2016-12-20T09:24:56.653

Maybe you should put that in the question to help out others trying to assist you. – Hampkade – 2016-12-20T09:26:44.900