3.5.Wiring Standards

• Ethernet cabling is an important thing to understand, especially if you’re planning to work on any type of LAN network. There are different types of wiring standards available:

  1. Straight-through cable (586A)

  2. Crossover cable (586B)

  3. Rolled cable (rollover)

  4. Hardware loopback

Straight-Through Cable

• The straight-through cable is used to connect a host to a switch or hub, or a router to a switch or hub.

• Four wires are used in straight-through cable to connect Ethernet devices.

• Notice that only pins 1, 2, 3, and 6 are used.

Crossover Cable

• The same four wires are used in this cable; and you just connect the different pins together.

• Crossover cables can be used to connect these devices: 1. Switch to switch 2. Hub to hub 3. Host to host 4. Hub to switch 5. Router direct to host

Rollover Cable

• Although rollover cable isn’t used for hooking Ethernet connections together, you can use it to connect a host to a router console serial communication (com) port.

• And if you have a router or switch, you use this cable to connect your PC running Hyper-Terminal or some other terminal-emulation program to the hardware.

Hardware Loopback

• In any talk about wiring, loopback isn’t so much a wiring standard as it is a way to redirect data flow.

• Sometimes you may need a computer to think it has a live connection to a network when it doesn’t, because it’s a good testing strategy and because you need a live network to install.

• In these cases, you will need to trick the PC into seeing its own output as input; and you do this with a loopback plug. It works a lot like a crossover cable except that it connects the transmit pins directly to the receive pins, as shown in Figure below.