Thursday, October 13, 2011

CCNA :: Part 1 - Internetworking



Ethernet Cabling
Ethernet cabling is an important discussion, especially if you are planning on taking the Cisco CCNA exam. The types of Ethernet cables available are:

    * Straight-through cable
    * Crossover cable
    * Rolled cable

Straight-Through Cable

The straight-through cable is used to connect

    * Host to switch or hub
    * Router to switch or hub
Four wires are used in straight-through cable to connect Ethernet devices. It is relatively simple to create this type; Fig. 7 shows the four wires used in a straight-through Ethernet cable.

                                                                        Fig - 7

Notice that only pins 1, 2, 3, and 6 are used. Just connect 1 to 1, 2 to 2, 3 to 3, and 6 to 6, and you’ll be up and networking in no time.

Crossover Cable

The crossover cable can be used to connect

    * Switch to switch
    * Hub to hub
    * Host to host
    * Hub to switch
    * Router direct to host

The same four wires are used in this cable as in the straight-through cable; we just connect different pins together. Fig. 8 shows how the four wires are used in a crossover Ethernet cable. Notice that here we connect pins 1 to 3 and 2 to 6 on each side of the cable.

                                                                 Fig - 8

Rolled Cable

Although rolled cable isn’t used to connect any Ethernet connections together, you can use a rolled Ethernet cable to connect a host to a router console serial communication (com) port with additional converter. If you have a Cisco router or switch, you would use this cable to connect your PC running HyperTerminal to the Cisco hardware. Eight wires are used in this cable to connect serial devices, although not all eight are used to send information, just as in Ethernet networking. Fig. 9 shows the eight wires used in a rolled cable.

                                                               Fig - 9

Once you have the correct cable connected from your PC to the Cisco router or switch, you can start HyperTerminal to create a console connection and configure the device. Set the configuration as follows:

    * Bits per second: 9600
    * Data bits: 8
    * Parity: none
    * Stop bits: 1
    * Flow control: none

No comments:

Post a Comment