Identify the appropriate media, cables, ports, and connectors to connect Cisco network devices to other network devices and hosts in a LAN Select the appropriate media, cables, ports, and connectors to connect switches to other network devices and hosts Ethernet cabling is an important discussion, especially if you are planning on taking the Cisco exams. Three types of Ethernet cables are available: • 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; Figure 1.12 shows the four wires used in a straight-through Ethernet cable.
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. However, remember that this would be an Ethernet-only cable and wouldn’t work with voice, Token Ring, ISDN, and so on.
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. Figure 1.13 shows how the four wires are used in a crossover Ethernet cable.
Notice that instead of connecting 1 to 1, 2 to 2, and so on, here we connect pins 1 to 3 and 2 to 6 on each side of the cable.
Rolled Cable
Although rolled cable isn’t used to connect any Ethernet connections, you can use a rolled Ethernet cable to connect a host to a router console serial communication (com) port.
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. Figure 1.14 shows the eight wires used in a rolled cable.
These are probably the easiest cables to make because you just cut the end off on one side of a straight-through cable, turn it over, and put it back on (with a new connector, of course).
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:
1. Open HyperTerminal and enter a name for the connection. It is irrelevant what you name it, but I always just use Cisco. Then click OK.
2. Choose the communications port—either COM1 or COM2, whichever is open on your PC.
3. Now set the port settings. The default values (2400bps and no flow control hardware) will not work; you must set the port settings as shown in Figure 1.14.
FIGURE 1.14 Port settings for a rolled cable connection
Notice that the bit rate is now set to 9600 and the flow control is set to None. At this point, you can click OK and press the Enter key and you should be connected to your Cisco device console port. We’ve taken a look at the various RJ45 unshielded twisted pair (UTP) cables. Keeping this in mind, what cable is used between the switches in Figure 1.15?
In order for host A to ping host B, you need a crossover cable to connect the two switches.
But what types of cables are used in the network shown in Figure 1.16?
The trouble is, we have a console connection that uses a rolled cable. Plus, the connection from the router to the switch is a straight-through cable, as is true for the hosts to the switches. Keep in mind that if we had a serial connection (which we don’t); it would be a V.35 that we’d use to connect us to a WAN.
Identify the appropriate media, cables, ports, and connectors to connect Cisco network devices to other network devices and hosts in a LAN Select the appropriate media, cables, ports, and connectors to connect switches to other network devices and hosts Ethernet cabling is an important discussion, especially if you are planning on taking the Cisco exams. Three types of Ethernet cables are available: • 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; Figure 1.12 shows the four wires used in a straight-through Ethernet cable.
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. However, remember that this would be an Ethernet-only cable and wouldn’t work with voice, Token Ring, ISDN, and so on.
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. Figure 1.13 shows how the four wires are used in a crossover Ethernet cable.
Notice that instead of connecting 1 to 1, 2 to 2, and so on, here we connect pins 1 to 3 and 2 to 6 on each side of the cable.
Rolled Cable
Although rolled cable isn’t used to connect any Ethernet connections, you can use a rolled Ethernet cable to connect a host to a router console serial communication (com) port.
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. Figure 1.14 shows the eight wires used in a rolled cable.
These are probably the easiest cables to make because you just cut the end off on one side of a straight-through cable, turn it over, and put it back on (with a new connector, of course).
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:
1. Open HyperTerminal and enter a name for the connection. It is irrelevant what you name it, but I always just use Cisco. Then click OK.
2. Choose the communications port—either COM1 or COM2, whichever is open on your PC.
3. Now set the port settings. The default values (2400bps and no flow control hardware) will not work; you must set the port settings as shown in Figure 1.14.
FIGURE 1.14 Port settings for a rolled cable connection
Notice that the bit rate is now set to 9600 and the flow control is set to None. At this point, you can click OK and press the Enter key and you should be connected to your Cisco device console port. We’ve taken a look at the various RJ45 unshielded twisted pair (UTP) cables. Keeping this in mind, what cable is used between the switches in Figure 1.15?
In order for host A to ping host B, you need a crossover cable to connect the two switches.
But what types of cables are used in the network shown in Figure 1.16?
The trouble is, we have a console connection that uses a rolled cable. Plus, the connection from the router to the switch is a straight-through cable, as is true for the hosts to the switches. Keep in mind that if we had a serial connection (which we don’t); it would be a V.35 that we’d use to connect us to a WAN.
