Home Networking Guide : Direct Connection - Wired (Cable) Solutions

If you have "only" two computers (desktop PCs or laptops) and want to share some files or a printer, a direct connection is a quick solution. Direct connection can be created using cable or wirelessly. You can also use a direct connection to connect more computers in a daisy-chain or star configuration, thus expanding your small network incrementally. And if one of your computers has access to another network (e.g. LAN or Internet), it can be configured to share the network access. This is a cheaper alternative to infrastructure-based network that requires a special hardware to implement, such as a wireless access point, hub, switch, or router.

Figure. Direct Connection using cable.

Null modem cable and DirectParallel cable

You can connect through serial (COM) port that has DB-9 or DB-25 male connector or parallel (LPT) port that has DB-25 female connector. An RS-232C null modem cable is used to connect two computers through serial port. A DirectParallel cable is used to connect two computers through parallel port. You can use serial or parallel port connection for file transfer or other network functions depending on the OS of your computer and the software you use. LapLink, pcAnywhere, and built-in Direct Cable Connection (DCC) of Windows are popular software for this application. If you use Windows XP, you can start with the New Connection Wizard. See this page for step-by-step instructions.

Ethernet crossover cable

If both computers have Ethernet adapters, you can connect them using a crossover cable. A crossover cable is an Ethernet cable (Cat 5 or better) that is pinned according to EIA/TIA-568A standard on one end and 568B on the other end. You can do anything as if you had a "complete" Ethernet network, e.g. file and printer sharing, Internet connection sharing, etc. The software setup for this configuration is similar with other Ethernet networks. In Windows XP, you can start with the Network Setup Wizard. See this page for step-by-step instructions.

USB cable and FireWire cable

USB and FireWire ports, typically used for connecting peripherals to computer, can also be used to connect two computers directly to form a network. Most today's computers have several USB ports available for connecting various devices, while FireWire port usually comes from extra graphic card or a special FireWire controller card. However, many high end computers come with built-in FireWire port.

Using a USB cable, you can connect directly two computers via USB ports but there is no built-in support in Windows for this kind of connection. You need a third party software which emulates a LAN adapter. Using a USB-to-Ethernet adapter, you can "convert" USB to Ethernet to connect it to an Ethernet crossover cable.

Using a FireWire cable, you can connect directly two computers via FireWire ports. You don't need additional software to connect two computers running Windows XP (or ME) using a FireWire cable. Windows XP has built-in support for FireWire networking, that's using IPv4 over IEEE 1394 (a.k.a. TCP/IP over 1394). A FireWire card is identified as 1394 Net Adapter and a 1394 Connection is created under LAN or High-Speed Internet in Network Connections folder. You can configure your network and Internet connection sharing using the Network Setup Wizard or manually from Network Connections folder. The step-by-step procedure is similar with that of direct connection using Ethernet crossover cable above. But the connection setup takes more time and the connection is less stable than Ethernet.

The primary advantage of using USB or FireWire is speed. USB 2.0 specification provides maximum data rate of 480 Mbps. FireWire (1394a) can connect at up to 400 Mbps and FireWire 800 (1394b) 800 Mbps. The disadvantages are for longer reach both need a repeater and the lack of built-in support in the Operating System because they were originally designed for connecting portable devices or peripherals.