Speed drop off when using a RJ45 splitter

[#1]

Hi There.

I have a Plusnet 2 router with a wired RJ45 connection to an outbuilding appx 50 metres away, powering my PC for day to day work. That works fine.

But when i plug in an RJ45 splitter in the outbuilding and try to run another device, ie a laptop, only one of the connections will operate.

Will i need something else to make it work?

I dont want to run another 50 metre RJ45 direct from the router so looking for other ideas?   

Thanks

[#2]

Do you have power in the outbuilding?  If so, if you connect a switch in there, then you can plug multiple devices in at the same time.  Something like this works well: https://www.amazon.co.uk/TP-Link-TL-SG105S-Ethernet-Lifetime-Warranty/dp/B07HP5TN4S

[#3]

Appreciate the quick response

Yes i do have power, Im using a non powered one at present, which isnt working.

Do you think a powered one will work better?

[#4]

@Danj2 

To work ethernet switches need power.

I did look at a passive one where you choose which connection is active - search Amazon for "CERRXIAN Network Lan Switch 2 Ports"

As mentioned to run multiple connections at the same time you need a powered switch.

Brian

[#5]

I don't think I've come across a switch that isn't powered in some way.    There's something else called a hub, which is different, which may have been able to use without power.  I've not used one for 25 years or so though, so can't remember.  I'm not sure if you could still get one.  The thing that I'd assumed you meant by RJ45 splitter, goes at either end of the cable and used 2 pairs of the cable for each socket, which would likely reduce the speed (depending on the speed of the equipment connected) and might not work depending on how the cable is wired.  Again, I've no idea if they are still a thing.  I've never used them myself.

I'd always go with a switch myself.

[#6]

When you say "splitter", do you really mean an Ethernet switch?

A switch is what you need to be able to multiply the number of devices using a single router Ethernet port.  They don't have an appreciable impact on speed.  For your application a simple unmanaged switch will work just fine.  It must be powered though, as a switch needs power to work.

A dumb cable splitter won't work.  The clashes that will occur between data packets will either mean neither device will work, or only one will work.  The unscrupulous sellers on online sites that sell these things really need to be taken down IMHO.

The good news is that something like a simple 4 port switch is pretty cheap.

[#7]

Thanks Guys really appreciate the advice, all seems to agree that i do need a powered switch as pjmarsh originally suggested.

Ill get on an order one and see if tha works.

Thank you all.

dan

[#8]

@Danj2  If the splitter is a small unit, usually plastic, with a plug on one side and a pair of sockets on the other then you need one either end of the ethernet cable. I must agree with the others a small switch is the way to go….

[#9]

The unit I referenced earlier is passive with a button that is pressed to choose which outgoing connection is in use. It describes itself as a switch and costs just over £13 (from you know where).

Brian

[#10 · Accepted solution]

Moderators Note

This topic has been moved from Broadband to My Router

[#11]

Amazon sells a variety of these sort of things... but descriptions need to be read carefully they have rj45/ethernet splitters:

• Note: This Ethernet splitter allows two computers to share one Ethernet line ONE AT A TIME, but it doesn't support both computers to connect onto the internet simultaneously. Just one output port is working.
• RJ 45 Splitter Connector: This is network splitter adapter, 1 RJ45 outlet to 2 RJ45 sockets.

But for a few pounds extra you can buy a "proper" ethernet hub/switch (also sometimes called a splitter I suppose) that needs to be powered and typically takes the input connection and creates an additional 4, 7, 15 or more ports.

The splitter either divides the cable into two seperate 2 pairs (instead of 4) connections (and needs one on each end) or allows you to switch all the cable pairs from one connector to the other (but not both at the same time.)