Ticky-tack complaint with Techexam's Net+ practice test

JDMurray

I just took your very nice Network+ practice test and I believe the answer to the following question (#49) is incorrect:

Which of the following network types need to be terminated?
a. 10BASE-T
b. 100BASE-TX
c. 10BASE2
d. 10BASE5
e. 100BASE-FX

The given answer is c and d. However, fiber (100Base-FX) also requires termination--although not by using 50ohm terminators. If the question were worded Which of the following network types need terminators?, then I'd agree that c and d were the only correct answers. Fiber is terminated by its connectors and not any type of shunt.

RussS

Care to share how you define termination?

JDMurray

Termination is a necessary quality for a comunications medium to function properly by dampening EM energy. In both electrical and optical mediums, termination dampens reflections of EM energy that would otherwise echo up and down the medium.

This can best be undestood by observing how a 10Base2 trunk line must have terminating shunts, but a 10BaseT network does not need terminators (i.e., the RJ-45 connectors do not act as terminating shunts). The ST and SC connectors used with fiber do act as terminating shunts by dampening reflections of the light travelling across the fiber.

Like I said, it is ticky-tack, but fiber is terminated by its connectors just as 10Base2 and 10Base5 trunks are terminated by their terminators
.

jrowe

IMO the fiber would not need to be terminated , as you say

The ST and SC connectors used with fiber do act as terminating shunts

in this case the termination is already there, but with 10base2 and 10base5 there is no termination unless terminators are added.

RussS

Well you have a good grasp of the theory so I don't need to go over that, however your comment

Fiber is terminated by its connectors and not any type of shunt.

answers itself. The connectors are terminators in themselves, therefore there is no need for 'terminators'.
It works much the same as a NIC on the end of a drop - remove the connection and you need to add a terminator, but the NIC is not usually refered to as a terminator in general speak. It has more to do with the transmission mode than the cabling type (see CSMA/CD and Token Ring).

JDMurray

The term termination is clearly an overloaded one. In fiber-speak, connectors are referred to as terminators and termination points. The connectors do absorb reflections, although they are not connected to the ends of a bus.

So a physical bus topology (e.g., 10Base2, 10Base5) requires termination of the trunk line, but physical star topologies (e.g., 100BaseT, 100BaseF) do not require termination of their drops. A 100BaseT/F NIC is not a terminator, because removing the cable from a T/F NIC does not affect the network.

Fiber vs. copper termination is clearly a case delving too deeply into a topic and over-thinking an exam question. :P

nethersdenizen

Don't worry about it, it's all in preparation for the real test which will have some not so clear questions in which some questions have no right choices or all right choices and you'll need to pick the best as far as CompTIA is concerned. I have a few disagreements with information presented here and other places based on experiences. Best thing to do is to learn it the CompTIA way for the test. On your own you can conceptualize things in a different way than others and that is fine. Not going to say your right or wrong because on different levels you are both.

But when it comes to network+ terminators are just for coax cable and killing machines sent back in time.

Sometimes people tell you check all your answers and to reread things so that a simple mistake doesn't happen but I find this causes some to over analyze questions thinking there is some sort of trick to it. If you passed your practice tests on the first try with at least an 80% you should be fine for the real test. Network+ is fairly basic and I passed with just a quick review of the tech-notes found on this site.

Best of luck in the exam room.