How-to Make Your Own Ethernet "splitter"

With an Ethernet "splitter", you can simultaneously connect two computers (or other network devices) on one Ethernet cable. You can buy Ethernet splitters for approximately $ 20.00 USD but you also can make your own.

Context:
One office, one ethernet jack and two computers, or
One living room, one ethernet jack and one HTPC and one XBox.

If you can't realistically (without tearing apart walls or renting a scissor lift) pull one more ethernet cable from the patch panel to the office / living room etc. you can consider the use of an Ethernet "splitter".

I'm assuming all the four pairs of the ethernet cables are properly connected within the ethernet wallplate and the patch panel.

Step 1: What You Need

In order do make your own Ethernet splitters you'll need the following:

• Two RJ45 Crimpable Plug
• Four RJ-45 keystone jack
• Short Ethernet Cable Scrap (approximately 2 feet)

The tools you'll need:

• RJ45 Crimp Tool
• Craft knife
• 110 Punch Down Tool
• Loctite Super Glue

Step 2: Crimp the RJ45 Plug to the Ethernet Cable

...using the following wiring scheme:

1 White/Orange
2 Orange
3 White/Green
4 Blue
5 White/Blue
6 Green
7 White/Brown
8 Brown

Taken from the excellent Hardware Book: www.hardwarebook.net/cable/network/ethernet10basetstraightthru.html

Step 3: Punch Down the Other End to the RJ-45 Keystone Jacks

Take the other end of the cable, cut it to 9 inches and punch down the four pairs using the following wiring scheme:

• Jack #1:

1 White/Orange to pin 1keystone jack
2 Orange to pin 2 keystone jack
3 White/Green to pin 3 keystone jack
6 Green to pin 6 keystone jack

• Jack #2:

4 Blue to pin 2 keystone jack
5 White/Blue to pin 1 keystone jack
7 White/Brown to pin 3 keystone jack
8 Brown to pin 6 keystone jack

Once all the pairs are punched down, you can glue together side by side the two keystone jacks.

Step 4: Make One More Splitter

...using the previous information so you end up having two splitters.

Step 5: Plug One Splitter to the RJ45 Wallplate

... and plug the two computers to the splitter.

Step 6: Plug the Other Splitter to the Patch Panel

...and plug two patch cords from the splitter to two free ethernet jacks from the switch. If your splitter connections are right the two leds "LINK" from the switch on which the patch cord are connected should turn on.

Step 7: Final Words

We now have two computers simultaneously connected using only one ethernet cable. This method is similar to PoE (Power over Ethernet) but instead of injecting DC, it is injecting another "data".

But again, it is better if you can to pull one more ethernet cable from the patch panel to the wallplate. But in some specific cases, the Ethernet "splitter" can help out.