# Computer Networks Questions & Answers – Multiplexing

This set of Computer Networks Multiple Choice Questions & Answers (MCQs) focuses on “Multiplexing”.

1. If there are n signal sources of same data rate, then the TDM link has _______ slots.
a) n
b) n/2
c) n*2
d) 2n

Explanation: Each signal source gets access to the entire channel bandwidth during its designated time slot in TDM since the total unit of time is distributed equally among all signal sources. When a source’s time slot isn’t active, it sits idle and waits for its slot to start.

2. If link transmits 4000frames per second, and each slot has 8 bits, the transmission rate of circuit this TDM is _________
a) 32kbps
b) 500bps
c) 500kbps
d) 32bps

Explanation: Transmission rate= frame rate * number of bits in a slot.
Given: Frame rate = 4000/sec and number of bits in slot = 8
Thus, Transmission rate = (4000 * 8) bps
= 32000bps
= 32kbps

3. The state when dedicated signals are idle are called __________
a) Death period
b) Poison period
c) Silent period
d) Stop period

Explanation: There are times when a connection is created between two endpoints, but no communication or message transfer occurs. Silent period is the name given to this period of time. When one of the two endpoints initiates communication, the silence time ends.

4. Multiplexing provides _________
a) Efficiency
b) Privacy
c) Anti jamming
d) Both Efficiency & Privacy

Explanation: Multiplexing allows us to send multiple messages over a single channel. This raises concerns about privacy and efficiency. Fortunately, when multiplexing is implemented, it has excellent efficiency and privacy because the transport layer of the OSI network architecture handles the function of multiplexing through interfaces called ports, which give the required efficiency and privacy.

5. In TDM, the transmission rate of a multiplexed path is always _______ the sum of the transmission rates of the signal sources.
a) Greater than
b) Lesser than
c) Equal to
d) Equal to or greater than

Explanation: In TDM, the transmission rate offered by the multiplexed path is always greater than the sum of the single sources’ transmission rates. This occurs because each source only receives the transmission rate for a short period of time.

6. In TDM, slots are further divided into _________
a) Seconds
b) Frames
c) Packets
d) Bits

Explanation: Time division multiplexing is abbreviated as TDM. It’s a method for integrating multiple low-rate channels into a single high-rate one. Several channels could occupy the maximum bandwidth for a given time slot. For a period of time, each channel is also inactive. Frequency division multiplexing and phase division multiplexing are two further multiplexing techniques.

7. The sharing of a medium and its link by two or more devices is called _________
a) Fully duplexing
b) Multiplexing
c) Micropleixng
d) Duplexing

Explanation: Multiplexing is a technique for simultaneously transmitting many signals through a shared media. This saves money by utilising fewer resources and lowering the cost of sending messages.

8. Multiplexing is used in _______
a) Packet switching
b) Circuit switching
c) Data switching
d) Packet & Circuit switching

Explanation: Circuit switching is a method of obtaining a physical path between two sites by switching on and off. A connection oriented network is another name for the circuit switching technology. To establish a circuit switching network, two nodes must be physically and logically coupled.

9. Which multiplexing technique used to transmit digital signals?
a) FDM
b) TDM
c) WDM
d) FDM & WDM

Explanation: TDM stands for Time Division Multiplexing, which is a digital signal processing technology. For analogue signals, the abbreviations FDM and WDM stand for Frequency Division Multiplexing and Wavelength Division Multiplexing, respectively. TDM is utilised in applications such as ISDN (Integrated Services Digital Network) and PSTN (Public Switched Telephone Network) (Public Switched Telephone Network).

Multiplexing is a technology that allows several communication signals to be combined in order to travel across a single signal communication media at the same time. Multiplexing is a technique that can be used with both analogue and digital signals. Each signal source gets access to the entire channel bandwidth during its designated time slot in TDM since the total unit of time is distributed equally among all signal sources. When a source’s time slot isn’t active, it sits idle and waits for its slot to start.