This cable connects a serial port on your computer to the console port of the device and it is used for the device’s initial configuration. Hence, the lab instructers use serial links because they match the ports available.Īlso, consider, that serial links usually require more configuration (clocking, speed, DTE/DCE type etc), and it's more advantageous for students to see the more complex configurations than the plug-and-play type ethernet interfaces tend to be. A rollover cable is usually shipped with each Cisco device.
Each end of the cable has a RJ-45 (or ISO 8877) connector. It is also sometimes used with serial ports between a router and a computer.Depending on the type of connection, we can use a rollover cable.A network cable consists of 8 wires, 4 pairs. I've noticed that most labs used for traiing are built from older or re-deployed hardware, and hence tend to be lower specification than the latest gear - and most older routers have serial ports available by default, or at least installed when theyw ere deployed because serial links were all they had. It is an especially useful cable for an ISP or for organizations where advanced routers are in use. Serial *interfaces* are not necessarily so. Serial *connections* are more expensive than ethernet. Crossover cables Connect routers back to back to simulate WAN links. What is the secret advantage that I still can not figure out? So why do they prefer to use serial cable? Some networking applications require an Ethernet crossover cable, which has a T-568A connector on one end and a T-568B connector on the other. Both the standards can be used for straight through cable.
Serial connection is more expensive and slower than Etherrnet cable. If both ends of the patch cords are wired on the basis of one standard, it is a straight through connection. It says that: "WANS are connected over serial lines and typically operate at lower speeds than LANs, and more expensive"