Fundamentals

Question 1

What is a network?

Answer 1

A network is a collection of nodes integrated together using media that can be wired or wireless. It’s comprised of two addresses: the source address and the destination address. The communication mode or mode of transmission of data can be of three types. Simplex, half duplex, full duplex.

Question 2

Simplex

Answer 2

one transmitter, one receiver. unidirectional

Question 3

Half duplex

Answer 3

communication can take place along both sides of the channel, one at a time. Efficiency less than 50%
bidirectional

Question 4

Full duplex

Answer 4

communication can take place along both sides of the channel simultaneously. Efficiency greater than 50%.
bidirectional

Question 5

Multiplexing

Answer 5

The process of combining various digital signals into one signal over a shared medium

Question 6

De-multiplexing

Answer 6

he reverse process done at receiver’s end, and thus, extracting the original signal at the receiver’s end.

Question 7

baseband transmission

Answer 7

a digital signal is sent over a channel without changing it to an analog signal. This transmission requires a low pass channel, a channel with a bandwidth that starts from zero. This happens only when we have a dedicated medium with a bandwidth constituting only one channel.

Question 8

Broadband transmission

Answer 8

hanging the digital signal to an analog signal for transmission. This change is done with the help of modulation, where other information is added to the signals. Modulation is allowed using a channel with a bandwidth that does not start from zero, which is called the bandpass channel.

Question 9

Twisted Pair Cable

Answer 9

Twisted pair is a widely used medium in networking because it’s lighter, cheaper, more flexible, easy to install, and provides greater speeds than coaxial cables.

There are two types of twisted pair cables: the unshielded twisted pair (UTP) and the shielded twisted pair (STP)

lighter, cheaper, and more flexible than coaxial

Question 10

unshielded twisted pair cable

Answer 10

has 4 pairs of copper wires that are present inside a plastic sheath. These wires are twisted to protect them from interference. The only protection available for a UTP cable is a plastic sheath that is thin in size

Question 11

shielded twisted pair cable

Answer 11

widely used in high-speed networks. The major difference between UTP and shielded twisted pair is that STP makes use of a metallic shield to wrap the wires. This metallic shield prevents interference to a better extent than UTP. These STP cables come with numbering; the higher the numbering, the better the interference prevention. Most computer networks must go with CAT 3 or CAT 5, and nothing less than this.

Question 12

Coaxial Cables

Answer 12

central copper conductor, surrounded by an insulating layer, a conducting shield, and the outermost plastic sheath.

Cable TV and analog televisions mainly use coaxial cables. Coaxial cables have better resistance to cross talk than twisted pair cables. The coaxial cables are used for long distance communication.

Question 13

Optical Fibers

Answer 13

high speed and bandwidth, costliest, travels through lightwaves, no crosstalk or attenuation,

single mode- long distance, one connection
multi mode- shorter distance, more connections

Question 14

Wireless/unguided transmission

Answer 14

radio wave/infrared/microwave