Networking – Rejoin split ethernet cable

ethernetgigabit-ethernetnetworking

In my apartment we have an old LAN network where every room is reached by ONE ethernet cable that splits in 2 ethernet ports, the same happens to the hub where 6 cables arrive (one from each room) and each splits into 2 ethernet ports.

There are two problems from this:

Only one of the 2 ports is working for each cable
The connection is slow, it looks like it's maxing out the bandwidth of each cable

50Mb/s through cable connection, >300Mb/s if connected directly to the modem or via wifi (where the wifi signal is strong enough).

From my basic understanding of networking, the cables have been hard split (I can see it in the hub and disassembling the ports sockets in the rooms), to allow more devices on the same cable, but modern hardware is not able to recognise this automatically, hence only one of the ports is working and moreover the split cables have limited bandwidth.

My question is:
Can I rejoin the split cables using a LAN splitter like this splitter?
Or do I have rewire manually the cables to one port instead of 2?

Doing so would I be able to achieve Gigabit ethernet (with a gigabit router)?

Best Answer

Rewire the cable at both ends using all 8 strands (http://logmett.com/index.php?/quick-tips/rj45-pinouts.html) and use a small gigabit hub to get more ports.

10/100 only requires 4 strands and they appear to have used an old trick of splitting the signal to enable two 10/100 connections on one cable.

Gigabit (10/1000) requires all 8 strands to be correctly wired at each end and cannot be split.

A quick and dirty fix could be made using powerline adapters, but no guarantees that it would work.

Related Solutions

Networking – How to securely run two LANs on a single ethernet cable

It will need two things:

Switches that support VLANs and VLAN trunking.
The router must have more than one ethernet port.

You have to create two VLANs and one Trunk on each switch :

Room B:

VLAN A - Ports that connect internal users
VLAN B - Port to Wireless access point
Trunk - Port to the only ethernet cable going to Room A

Room A:

VLAN A - Ports that connect file, server, firewall and router
VLAN B - Port that connect to second ethernet port on router
Trunk - Port to the ethernet cable coming from Room B

In this way, both VLANs share the ethernet cable through the Trunk.

The second port on the router must be on the 10.59.0.1/24 network and there should be only one route pointing outside, to avoid that guests can go to the internal network.

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Networking – Using ethernet cable (Cat 6) with phone jack

First of all, you can only have one modem/router on a single phone line. So if your jack in the bedroom is hooked up to the same phone line as the one in the living room then you can't get a new modem/router to have in your room.

You say there are two jacks in the living room. If one of them is used for hooking up the modem/router then what is the other one used for? Could that perhaps be connected to the jack in your bedroom? You can find that out by getting a phone line tracer (device that sends out sine waves over copper wires and its corresponding receiver) hook that up to your bedroom jack and take the receiver to the living room and see if it sees the signal. If you don't hear the signal there, then that means that the copper line connected into your bedroom has no connection with the copper lines connected in your living room and there is no way to get any signal between the two places using the preinstalled copper lines.

If you do hear the signal in the living room that means the jack in your bedroom is hooked up to the same line as the one in the living room.

Then there are two options.

This is all the same line, the line that goes into your current modem/router, the second plug in the living room and the plug in your bedroom. Then you can't use that line to transmit any extra data.
The second plug in the living room is connected with your bedroom plug, but the plug which the modem/router hookes up with is not connected to that same line. Then if there are 4 wires between the living room and your bedroom you are in luck. An internet cable really only needs 4 wires, which is what the RJ11 plugs (I am assuming here that the plugs in the living room and your bedroom are RJ11 plugs, look them up if your not sure) are. So you can create or have someone create two cables with RJ11 on one end and RJ45 on the second end. Hook one of them up to the modem/router and to the living room plug the other one would then go to your bedroom plug and to your computer. Voila, you got fast internet. On the other hand, if there are only two wires connected between your bedroom and living room, your out of luck.

So basically to use the plug in your bedroom you need four wires in that plug that connects to the empty plug in the living room and those wires can not be connected to the plug that your router connects to.

A second solution to get net to your bedroom is using the electricity wiring. See for example this cnet article for options of makes and modules to do this.

Best Answer

Related Solutions

Networking – How to securely run two LANs on a single ethernet cable

Networking – Using ethernet cable (Cat 6) with phone jack

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