Guide for a Computer to Computer via Ethernet Connection

This is a guide to connect two computers without the need of using a router, switch or hub. There are two methods of networking between two computers: Physically, using a Ethernet wire or using radio waves with an Wireless Ad-hoc (also known as Computer-to-Computer or Peer-to-Peer) connection.

Since there’s no router, switch or hub in between them there not a DHCP to assign each computer an IP address Server and a Default Gateway, you will first have to manually specify an Address for the Connection and a Default Gateway (not for Internet but for File and Printer Sharing). If you don’t do this, Windows will look for an Alternative Configuration and give it an Automatic Private IP Address (APIPA) by default, which although will only give you a “Limited or No Connectivity” status in you network.

The pros to a Crossover Cable connection is that the transfer speed is much faster and reliable than the wireless speed and requires less configuration steps, but you have to get or make a Crossover cable. On the other hand the Wireless Connection is frees you having to physically connect the computers and limitations on distance based wire length, but takes more configuration steps and is slower by today’s standarts

Steps to Manually Specify an IP Address and Default Gateway

Click the Start Button.

Open the Control Panel by clicking on the list, and double click on “Network Connections” (highlighted).

The Network Connections window will appear.

Right click on the device you want to change the settings – usually named “Local Area Connection”

for the Crossover Cable or “Wireless Network Connection” for the Wireless Ad-hoc --

and select ‘Properties’.

The Network Connection Device Properties will appear.

Highlight the item named‘Internet Protocol TCP/IP’ and click on Properties.

Once the Internet Protocol (TCP/IP) Properties dialog shows up, click on the Alternate Configuration tab.

Select User Configured option and specify the IP Address and Default gateway of your choice between 192.0.0.1 and 192.168.255.254.

Remember that you need to specify a different address and a common Default Gateway for each computer.

The Subnet mask will appear automatically once you enter the IP Address.

Note that the IP Addresses in the Computer #1 (left, 192.168.1.15) and Computer #2 (right, 192.168.1.16) are different and that the Default gateway (192.168.69.70) values are identical.

Once you’re finished, click the OK button.

Now you can proceed connecting plugging the wire or configure the wireless settings for your routerless network.

Computer-To-Computer Wired Ethernet Connection

Once Steps to manually specify an IP Address and a common Gateway for each computer you can plug the Ethernet Crossover Cable and start using the network.

A Ethernet Cable is actually a group of 8 insulated wires with another plastic insulation sheet around them with two RJ-45 jacks on each end. An Ethernet Crossover Cable has the transmit and receive wires inverted between ends. That way, the computers can communicate between themselves faster since they don’t have to change the signals on each pin.

You can buy an Ethernet Crossover Cable at any Walmart, Office Depot, Computer or even Home Depot store, or you can do one by yourself. All you have to do is interchange 4 of the wires as shown on the table.

Signal Pin Color Color Pin SignalTransmit + 1 Orange / White Green / White 3 Receive +Transmit - 2 Orange Green 6 Receive -Receive + 3 Green / White Orange / White 1 Transmit +Unused 4 Blue Blue 4 UnusedUnused 5 Blue / White Blue / White 5 Unused

Receive - 6 Green Orange 2 Transmit -Unused 7 Brown / White Brown / White 7 UnusedUnused 8 Brown Brown 8 Unused

Once you got the cable all you have to do is plug the ends on each computer Ethernet Network port. (Looks like a phone jack, only bigger).

That’s it, unlike the wireless connection there’s no further configuration needed.

Computer-To-Computer Wireless Connection

In order to create and Ad-hoc Wireless Network both computers need to match the wireless network name (SSID) and channel. The Windows Wireless Zero Configuration only lets you specify the SSID and seems to use a default channel. Other wireless configuration applications such as ‘Dell Wireless Configuration Utility’ are more flexible and easier to use.

These are the steps to configure the network settings using the Windows Wireless Zero Configuration.

Once again, open the Network Connections window and select your wireless device (usually named “Wireless Network Connection”).

This time click the “Wireless Networks” Tab, locate the Advanced button and click it.

Make sure the ‘Any available network (access point preferred).’ is selected and click ‘Close’.

Now you we will proceed to specify the SSID and a network security key so nobody but the people you want can access the network.

Click the “Add…” button to open the “Wireless network properties” dialog.

Enter the name you chose for your network On the Network name (SSID) and then uncheck ‘The key is provided for me automatically’ in the Wireless network key section.

Now enter the security password for your network in the “Network key” and “Confirm network key” fields.I recommend using a WEP Data encryption for backward compatibility, consequently, for WEP encryption

the key can be only 5 or 13 characters long.

Make sure you the “This is a computer-to-computer (ad-hoc) network; wireless access

points are not used” option is checked andclick the OK button.

That’s pretty much it for the wireless configuration. Once the Wireless Network properties are set,

the computer should start looking for each other.

A Note about The Connection Process

Once you finished all the configurations and plugged everything you have to plug, you will notice that it takes a little longer to acquire a network address than it does with a router in the middle. That’s because both computer are expecting a DHCP server on the other side to assign them such address.

After a minute or two the computers will stop waiting and go for the settings specified in the Alternate Configuration in the Internet Protocol (TCP/IP) Properties, whether they are an Automatic private IP address (APIPA) or (in our case) an alternate manually configured (user configured) address.

This is true for both wired and wireless connections.