Ethernet cables are the most common network cables you will encounter. All networked devices on a Local Area Network (LAN), such as your PC, a network printer, a networked copy machine, a Server (Windows or Unix) etc use an Ethernet Cable to communicate with the rest devices on the network. Ofcourse, each of these devices is connected to an Ethernet Switch which is the heart of a LAN network.
The standard Ethernet network cable used today is the Cat5 or Cat5E (Enhanced) which is a twisted pair cable containing four pairs of copper wires. Some installations also use Cat6 type which is the newer version supporting higher data rates. The connector used for ethernet cables is the 8-pin RJ45 connector plug, as shown in the figure below.
All Ethernet cables support communication over distances of 100m. The older Cat5 cable uses only two pairs to support 100Mbps (Fast Ethernet). The enhanced version Cat5E uses all four wire pairs to support data rates of 1000Mbps (Gigabit Ethernet). Cat6 types support 10Gbps (ten Gigabit) data rates.
Straight Through Vs Crossover Cable
Normally you will need a straight through cable to connect your PC, server, network printer etc. Whatever is connected to a Network switch uses straight through cable. However, whenever you connect two “similar” devices together ( e.g PC with PC, switch with switch, router with router) you need a crossover cable. This looks the same as the straight cable, but the internal wires are connected differently on the RJ45 connector.