This is the standard connection for use between computers. This connector looks just like a telephone connection (RJ 11), but it is slightly larger (about ½ inch compared to about 5/8 inch).

Each computer must have a NIC (Network Interface Card). The cable used is a CAT5 or CAT5e (enhanced) and supports both older, slower 10 mps networks (needed where the computer's NIC is only rated for 10 mps), and 100 mps which is now the standard. High speed 1,000 mps (1 gigabite) connections require a CAT 6 or fiber cable, but they are usually only used for backbones (when two servers are being connected).

While two computers can be directly connected to each other in a peer to peer network, they require a special "cross over" cable where the wires are connected to the pins differently. All other networks will connect each computer (both clients and servers) to a Hub or Switch, which also uses an RJ 45 connection.