2.1 Select the appropriate media for various situations.

Media choices include:
Twisted-pair cable
Coaxial cable
Fiber-optic cable
Wireless
Situational elements include:
Cost
Distance limitations
Number of nodes
 

The two major cable types of twisted pair cable are Unshielded Twisted Pair (UTP), and Shielded Twisted Pair (STP).

Twisted-pair cable We’ve already discussed the twisted-pair and shown its diagram in chapter one, here we just show the difference between the UTP and STP. UTP (Unshielded twisted pair) is more popular because it is very pliable and doesn’t take up as much room in ductwork STP does.

Shielded twisted pair is wrapped in a metal sheath for added protection against external interference. If your network is in a noisy electronic environment, STP is preferred.

The trickiest part of FTQ 2.1.10 regarding UTP and STP has to do with the cost. Thus, you can eliminate fiber optic as the correct answer. The other items to consider are the space in the ceiling and crosstalk. Space issue is more important than the crosstalk in FTQ 2.1.10 because the space on the ceiling is really limited. Therefore, if you don’t have any electricity devices, you will not encounter external interference.

Pay attention to the fact that the question asks you to provide the cheapest solution. STP is more expensive. In addition, shielding and insulating make the cable thicker and you may even not be able to fit into the one-foot ceiling space. Therefore, you must choose UTP for the correct answer.

In order to pass the Networking Essentials exam, please try to remember the information on the following table.

The Networking Essentials MCSE Self-Paced Training Kit (by Microsoft Press) suggests people to use Category 5 UTP as the first choice. In reality, you can just wire the stations with ThinNet, which means you don’t need spend extra money on the Hub. Another issue you may have to consider is whether the network is easy to maintain and manage, at this time, twisted-pair with star topology is the correct answer.

To build a twist-pair network with star topology is definitely more expensive than just building it with thinnet cable and bus topology.

For FTQ 2.1.5, please note C is also a valid answer, if it is the multiple choice, you should choose A and C, because the problem statement doesn’t specify the cost. As such, fiber optic is a better solution. If the problem statement doesn’t include fiber optic as one of the answer choices, you should choose Cat5 cable. Only Cat5 and fiber optic can support above 100M network. But Fiber optic also can support 600M to 2GB ATM network.

If a question asks you for 100BaseT network, Cat5 UTP is the correct answer. Are you forgetting that 100BaseT is a twisted-pair Ethernet? You must choose twisted-pair as the correct answer.

Q: In question no. 2.1.5 you have given A. or fiber optics as the answer. But in your notes, 10 base F means bandwidth is 10mbps. Also mentioned again in 1.8, 3rd paragraph from last. Please comment.

A: The transmission speed for 10BaseF is 10Mbps. However, fiber optic can also be used in FDDI (100Mbps) and ATM (155Mbps), which >=100Mbps.