In the old days when the first personal computers were launched, the only way to transfer data from one computer to another was through removable storage devices like tape drives and floppy drives. Later developers have come up with direct link through serial (COM) or parallel (LPT) ports. This solution was almost as slow as copying data to a floppy disk and retrieving it on the other computer but had the convenience of not having to use unreliable floppy disks or tapes. These direct links had a maximum speed of 50-150kilobytes/s, basically like a very slow Internet connection today.
Network cards have also been developed to hook up hundreds of personal computers in the same building (or local area).
Today connecting two computers is most frequently done by connecting both computers to the world wide web and/or a local area network through a crossover UTP cable, USB cable that simulates two network cards connected to each other through UTP cable, or through Wi-Fi technology.
The most convenient solution is of course the Wi-Fi connection because it’s very easy to set up and the transmission speed has also been improved to match the speed of a wired network. The latest Wi-Fi specifications (IEEE 802.11n) support a 600MBPS maximum transfer rate, while wired networks can reach 1000MBPS (1GBPS) speeds in optimum conditions.
Wireless adapters supporting this relatively new technology can be found in almost all new laptops sold today.
The easiest way to set up a Wi-Fi connection between two computers is to use a wireless router. This idea may look absurd at first, but there’s a very logical explanation: most wireless routers come fully configured for wireless networking, so all you have to do is plug them in an AC outlet. This way both computers will detect the newly created wireless network and will receive local IP addresses, network masks and everything needed for the connection to work, if the wireless network cards are set to request IP addresses automatically (this is usually the default setting).
Another solution is to set up an Ad Hoc Wi-Fi connection, but this will require more time to set up. Network name (SSID), IP address, network mask, default gateway …etc have to be set on both computers.
Some wireless adapters however come with flexible drivers and software that let the user configure one computer as a virtual access point so all computers nearby could connect to it with automatic settings.
This solution is still more complicated than the wireless router solution, but if you configure your computer once to function as a virtual Wireless Access Point, then wherever you go any computer will be able to connect to yours automatically, with the risk of connecting more computers nearby that are also set to connect automatically.
A UTP network cable is a more secure way to connect two computers, and practical too, because on-board UTP network cards can be found in all computers manufactured since ~2005 (with very few exceptions).
Just like the Ad Hoc connection, both computers have to be configured by hand. One of them will have to look like this:
The most important thing to remember is that you have to give a different IP address to the other computer from the same class (ex: 192.168.0.2):
It’s unclear whether the workgroup has to be the same on both computers. Personally I have successfully connected computers from different workgroups too, so I recommend changing it (so both PCs will be in the same workgroup) only if you’re unable to see/access the other computer’s resources through the connection.
To make a computer-to-computer connection you’ll need a crossover UTP cable, which will allow 1000MBPS (~125Megabytes/s, the speed of an average desktop hard drive) transfer rate in both directions.
