Can I use a ethernet splitter to connect a router to two devices?

Question

I have a portable mini wireless router with different functions (AP/Client/Router).

Can I use a ethernet splitter to give internet access to two devices? The router only has a ethernet port and connects to a wireless network (Cliente mode).

I know that a switch would be the best option but I dont have one and they are expensive.

Solution

No.

A star shared regular Ethernet network can not be split by just tying cable together. If you want to connect two devices simultaneously to the same cable then you ether need a hub or a switch.

The device you are showing in your post is either one of these two:

1. A physically wired 1:1 splitter which means that you need to switch off one of the devices connected to it while the other is connected.
2. Or a dual 100mbit Ethernet over a single 8 wire cable.

The explain these a bit more:
Plain old 10/100 Mbit Ethernet has a standard cable with 8 wires, 4 of which are used. If you creatively rewire a few of these and (un)rewire those at the other end you can use two fully independent connections of the single cable.

Note that this just act as two cables in a single cable package and that you still need something to get the devices to talk to each other.

Comments

[NeDark]

@DavidPostill that question didnt help, i read it before. It looks Hennes answer is adequate for my case

[NeDark]

@barlop it's expensive compared to a splitter, i cant find one in ebay under $10

[barlop]

@NeDark I suggest trying social security(e.g. support for people on a low income if that's an option in your country)..or if you're young, then parents(i'm sure they can afford something <$20 even if they pretend otherwise). travelling to get somewhere where I live is typically more than $10. as you say, does seem to be a a bit more than $10 as you say but anyhow here is one on buy it now for $5 ebay.com/itm/…

[NeDark]

@barlop thanks for your suggestion, it looks i can use an old router as a switch ehow.com/how_2308635_use-router-switch.html

[barlop]

@NeDark yes turn off NAT and DHCP and also something mentioned here. forums.whirlpool.net.au/archive/1996394 give it an IP on the same network but outside the DHCP range. I think that's so that a)you can access the web interface b)so it doesn't give another computer the same IP as the device you're using as a switch

[barlop]

Just curious, with a hub, I guess you avoid a collision by a device checking if the cable is free. Why doesn't that work or happen with case '1'('the physically wired 1:1 splitter')? If you have a A,B-------C. Now then B sends to C, can A not detect that there is something on the wire?

[Loren Pechtel]

I have seen it work on hardware something like 10 years old (some electrician imagined themselves able to deal with networking.) Error city but the network resent the lost packets and thus it pretty much worked. This was under very light load conditions.

[David Schwartz]

Actually, if you look closely at his problem description, a switch won't work either. His router is connected in client mode, and so it will bind to the first hardware address it sees.

[ganesh]

I am not sure how to parse a client mode. I read it as it is a AP with a wired and a wireless connection. Is it a 'wired to wireless bridge'-ish thingy which uses the wired NICs MAC as wireless MAC?

[NeDark]

The mini router has NAT and DHCP built in, I guess it will work but I'll tell when I try

[NeDark]

@Hennes no, the mini router has a fixed MAC for wireless and a fixed MAC for ethernet. It support NAT and the deviced connected to ethernet is put on a different subnet. Example: Wireless network: 192.168.1.0/24, router wireless client IP: 192.168.1.66, router ethernet nat gateway: 192.168.2.1, device ip: 192.168.2.91 (Wireless network - Mini router - Device)

[T.J.L.]

The middle line of that diagram is bad... it uses D twice.

[ganesh]

Wow. You are right. And possible the first to notice since it was posted on 2014... Diagram corrected D E F G -> E F G H and cabled to cables. And after correcting I guess 'wires' would have been better.