04 The Purpose of Straight-Through and Crossover Cables.pptx
- 1. Networking
- 3. ◦ Straight-through cables get their name from how they are made. Out of the 8 pins that exist on both ends of an Ethernet cable, each pin connects to the same pin on the opposite side.
- 4. Notice how each wire corresponds to the same pin. This kind of wiring diagram is part of the 568A standard. The 568B standard achieves the same thing, but through different wiring. It is generally accepted to use the 568A standard as pictured, since it allows compatibility with certain telephone hardware- while 568B doesn’t.
- 5. ◦ Straight-through cables are primarily used for connecting unlike devices. A straight-through cable is typically used in the following situations:
- 6. ◦ Connecting a router to a hub ◦ Connecting a computer to a switch ◦ Connecting a LAN port to a switch, hub, or computer
- 7. Note: That some devices such as routers will have advanced circuitry, which enables them to use both crossover and straight-through cables. In general, however, straight-through cables will not connect a computer and router because they are not “unlike devices.”
- 9. ◦ Crossover cables are very similar to straight-through cables, except that they have pairs of wires that crisscross. This allows for two devices to communicate at the same time. Unlike straight- through cables, we use crossover cables to connect like devices.
- 10. Notice how all we did was switch the orange- white and green-white wires, and then the orange and green wires. This will enable like devices to communicate. Crossover cables are typically used in the following situations:
- 11. Connecting a computer to a router Connecting a computer to a computer Connecting a router to a router Connecting a switch to a switch Connecting a hub to a hub
- 12. ◦ While the rule of thumb is to use crossover cables with like devices, some devices do not follow standards. Others provide support for both types of cables. However, there is still something that both crossover and straight-through cables can’t do.