Explore topic-wise InterviewSolutions in .

This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.

1.

Routers operate at layer _____. LAN switches operate at layer _____. Ethernet hubs operate at layer _____. Word processing operates at layer _____.

Answer» Routers operate at layer 3. LAN switches operate at layer 2. Ethernet hubs operate at layer 1. Word processing applications communicate to the Application layer interface, but do not operate at layer 7, so the answer would be none.
Discussion
2.

How to implement a network medium that is not susceptible to EMI. Which type of cabling should you use?

Answer» Fiber-optic cable provides a more secure, long-distance cable that is not susceptible to EMI interference at high speeds.
Discussion
3.

Segmentation of a data stream happens at which layer of the OSI model?

Answer» The Transport layer receives large data streams from the upper layers and breaks these up into smaller pieces called segments.
Discussion
4.

When data is encapsulated, which is the correct order?

Answer» The encapsulation method is data, segment, packet, frame, bit.
Discussion
5.

What type of RJ45 UTP cable is used between switches?

Answer» To connect two switches together, you would use a RJ45 UTP crossover cable.
Discussion
6.

What is the purpose of flow control?

Answer» Flow control allows the receiving device to control the transmitter so the receiving device's buffer does not overflow.
Discussion
7.

Which three statements are true about the operation of a full-duplex Ethernet network?

Answer» Full-duplex means you are using both wire pairs simultaneously to send and receive data. You must have a dedicated switch port for each node, which means you will not have collisions. Both the host network card and the switch port must be capable and set to work in full-duplex mode.
Discussion
8.

What are two purposes for segmentation with a bridge?

Answer» Bridges break up collision domains, which allow more bandwidth for users.
Discussion
9.

Why does the data communication industry use the layered OSI reference model?

Answer» The main advantage of a layered model is that it can allow application developers to change aspects of a program in just one layer of the layer model's specifications. Advantages of using the OSI layered model include, but are not limited to, the following: It divides the network communication process into smaller and simpler components, thus aiding compo- nent development, design, and troubleshooting; it allows multiple-vendor development through standardization of network components; it encourages industry standardization by defining what functions occur at each layer of the model; it allows various types of network hardware and software to communicate; and it prevents changes in one layer from affecting other layers, so it does not hamper development.
Discussion
10.

A receiving host has failed to receive all of the segments that it should acknowledge. What can the host do to improve the reliability of this communication session?

Answer» A receiving host can control the transmitter by using flow control (TCP uses Windowing by default). By decreasing the window size, the receiving host can slow down the transmitting host so the receiving host does not overflow its buffers.
Discussion
11.

Which fields are contained within an IEEE Ethernet frame header?

Answer» An Ethernet frame has source and destination MAC addresses, an Ether-Type field to identify the Network layer protocol, the data, and the FCS field that holds the answer to the CRC.
Discussion
12.

What type of RJ45 UTP cable do you use to connect a PC's COM port to a router or switch console port?

Answer» To connect to a router or switch console port, you would use an RJ45 UTP rolled cable.
Discussion
13.

How does a host on an Ethernet LAN know when to transmit after a collision has occurred?

Answer» Once transmitting stations on an Ethernet segment hear a collision, they send an extended jam signal to ensure that all stations recognize the collision. After the jamming is complete, each sender waits a predetermined amount of time, plus a random time. After both timers expire, they are free to transmit, but they must make sure the media is clear before transmitting and that they all have equal priority.
Discussion
14.

Acknowledgments, sequencing, and flow control are characteristics of which OSI layer?

Answer» A reliable Transport layer connection uses acknowledgments to make sure all data is transmitted and received reliably. A reliable connection is defined by a virtual circuit that uses acknowledgments, sequencing, and flow control, which are characteristics of the Transport layer (layer 4).
Discussion
15.

What are the decimal and hexadecimal equivalents for the binary number ?

Answer» You must be able to take a binary number and convert it into both decimal and hexadecimal. To convert to decimal, just add up the 1s using their values. The values that are turned on with the binary number of 10110111 are 128 + 32 + 16 + 4 + 2 + 1 = 183. To get the hexadecimal equivalent, you need to break the eight binary digits into nibbles (4 bits), 1011 and 0111. By add- ing up these values, you get 11 and 7. In hexadecimal, 11 is B, so the answer is 0xB7.
Discussion
16.

Which layer 1 devices can be used to enlarge the area covered by a single LAN segment?

Answer» Not that you really want to enlarge a single collision domain, but a hub (multiport repeater) will provide this for you.
Discussion