Answers to Review Questions (Network+ Chapter1)

Answers to Review Questions

1. B, C. Computers participating in a peer-to-peer network can be either client or server or both. Additionally, the peer-to-peer model has some practical limitations, including the number of computers involved. Answer A is incorrect because the administration is not centralized. Answer D is incorrect because the use of hubs is not related to the implementation of peer-to-peer or client/ server networks.

2. D. The 10G in the 10GBase-SR designation can be thought of as standing for 10Gbps or 10,000Mbps, whichever helps you remember.

3. C, D. MT-RJ and LC are both forms of SFF fiber connectors. FC and SC are larger and do not permit the port density afforded by the other two.

4. A. Looking at the Link LED first could save you the frustration of waiting for the Activity LED to light up, which may never happen as long as there are issues with network connectivity (indicated by a dark Link LED).

5. B. The major advantage to mesh networks is their increased reliability. There are multiple redundant connections between all nodes in the network. Answer A is incorrect because the cable costs are much, much more than other networks. Answer C is simply a distracter; mesh is not required by fire codes. Answer D is incorrect because most token-based networks could not operate in a mesh environment.

6. B, D. The star topology has the advantage of simplifying the troubleshooting process because, when a device fails, you should check that device and its NIC, the network cable connected to
that NIC, and the port on the concentrating device (hub, MAU, switch, etc.) to which the other end of the network cable is connected. Somewhat related to this point, it also has the advantage
of localizing problems to the single device or cable segment. While it is true that the central concentrating device is a single point of failure, this is one of the disadvantages of star topologies.

7. A, B. The two early ring speeds of Token Ring were 4Mbps and 16Mbps

8. A. Of the physical topologies, the mesh has the most physical connections per device. This complete interconnection is what creates the mesh. The mesh is not used in the majority of LAN
implementations, mostly with WAN links. The most common physical LAN topology is the star topology. Answer C describes a physical ring topology, and D describes a logical bus topology.

9. B. There are only two main types of FireWire connectors, the 4 pin and the 6 pin. The 6-pin connector has two extra pins that provide power from the computer to the device.

10. B. Answer B is the only correct answer because plenum-rated cable meets fire codes for installation in suspended ceilings, raised floors, and any other open area through which ventilation-system air is returned. Plenum cable actually has a higher cost than PVC. Additionally, because the conductors are also made of copper, it doesn’t conduct data any faster than PVC-coated cable.

11. B, D. Both the SX and LX standards of gigabit Ethernet are based on fiber-optic cable, not copper. However, while 1000Base-LX permits the use of single-mode fiber over distances of 2000m,
it does not use the FC connector. Both it and the SX standard allow the use of SC or LC connectors on multimode fiber over a distance of 550m.

12. B. If your PC does not have native connectivity, say via TCP/IP, with a mainframe, none of the devices will assist you in communicating with the mainframe. The only help a router would be is if the mainframe were not on the same LAN segment, but it would have to speak the same protocol as your laptop or a gateway would still be necessary. Of all the answers, gateway is decidedly
the best.

13. D. 100Base-FX can be ruled out immediately because the
 F indicates a fiber-optic media dependency, while more subtly, 1000Base-CX can be quickly eliminated due to its media dependency on STP, not UTP. 1000Base-T is incorrect because, although it calls for the use of Category 5e UTP, it requires all four pairs for both transmit and receive use.

14. D. In broadband communications (television communications, for example), the communications medium is divided into discrete channels. Each channel can carry its own signal. In baseband
communications, the transmission takes up the whole communications channel. Full duplex communications give a sender and receiver the ability to each send and receive signals
simultaneously. Sideband is a distracter.

15. C. Although all the devices listed can be purchased with the variety of interfaces necessary to satisfy the objective, an external transceiver’s sole purpose is to change the type of media a NIC or
device interface connects to (provided there is a transceiver port available on the NIC or that you purchase a transceiver with th e appropriate interconnections).

16. C. Although you can wire any combination of pairs in an RJ-45 connector, you should wire all four pairs in a Category 5 UTP into an RJ-45 connector to support those network technologies
that may need all four pairs (such as 1000Base-T), even if you aren’t currently using them. Additionally, this habit supports all currently available technologies. So, in case you decide to change
from Token Ring to Ethernet, if you create a straight-through wired channel, there is no reason to rewire any cables because the popular wire pairing standards will cover both of these technologies
and many more.

17. C. The maximum segment length for 10GBase-SR is 300 meters. 

18. C. The Channel Service Unit/Data Service Unit (CSU/DSU) translates LAN signals into signals that are used on T1 lines. Some people incorrectly call it a “T1 modem.” It’s not a modem
because it doesn’t translate data into analog and back. Every signal stays in the digital format.

19. B. Although a router possesses certain access control capabilities, a firewall’s hardened configuration set makes it a superior choice for establishing a secure entryway into a LAN, blocking malicious traffic with pinpoint accuracy while allowing trusted traffic access to the internal resources. A proxy server may include some firewall capabilities, but not to the level of a standalone firewall. Besides, in the end, the proxy component that provides this functionality is a firewall, making it the best answer here. HTTPS is not a function of NIC cards, nor would hardening
a NIC card help guard an entire LAN against outside threats.

20. B. 100Base-TX works fine with two pairs of at least Category 5 UTP, but due to the fact that 1000Base-T uses all four pairs simultaneously (a reason D is incorrect), a minimum of Category
5e UTP is required for proper functioning. Both of these standards are specified over twistedpair copper (the T in their name signifies this), not fiber optics. Both standards are limited to the
same 100m segment length.