Physical Layer

Question 1
To send same bit sequence, NRZ encoding require
A
Same clock frequency as Manchester encoding
B
Half the clock frequency as Manchester encoding
C
Twice the clock frequency as Manchester encoding
D
A clock frequency which depend on number of zeroes and ones in the bit sequence
ISRO CSE 2020   Computer Network
Question 2
If there are n devices (nodes) in a network, what is the number of cable links required for a fully connected mesh and a star topology respectively
A
n(n-1)/2 , n-1
B
n, n-1
C
n-1, n
D
n-1, n(n-1)/2
ISRO CSE 2017   Computer Network
Question 3
In networking terminology UTP means
A
Uniquitous teflon port
B
Uniformly terminating port
C
Unshielded twisted pair
D
Unshielded T-connector port
ISRO CSE 2017   Computer Network
Question 4
Physical topology of FDDI is?
A
Bus
B
Ring
C
Star
D
None of the above
ISRO CSE 2017   Computer Network
Question 5
Bit stuffing refers to
A
inserting a 0 in user stream to differentiate it with a flag
B
inserting a 0 in flag stream to avoid ambiguity
C
appending a nipple to the flag sequence
D
appending a nipple to the use data stream
ISRO CSE 2016   Computer Network
Question 6
How many characters per sec (7 bits + 1 parity) can be transmitted over a 2400 bps line if the transfer is synchronous ( 1 start and 1 stop bit)?
A
300
B
240
C
250
D
275
ISRO CSE 2015   Computer Network
Question 7
What frequency range is used for microwave communications, satellite and radar?
A
Low frequency: 30 kHz to 300 kHz
B
Medium frequency: 300 kHz to 3 MHz
C
Super high frequency: 3000 MHz to 30000 MHz
D
Extremely high frequency: 30000 kHz
ISRO CSE 2015   Computer Network
Question 8
A T-switch is used to
A
Control how messages are passed between computers
B
Echo every character that is received
C
Transmit characters one at a time
D
Rearrange the connections between computing equipments
ISRO CSE 2015   Computer Network
Question 9
Consider a 50 kbps satellite channel with a 500 milliseconds round trip propagation delay. If the sender wants to transmit 1000 bit frames, how much time will it take for the receiver to receive the frame?
A
250 milliseconds
B
20 milliseconds
C
520 milliseconds
D
270 milliseconds
ISRO CSE 2014   Computer Network
Question 10
In the Ethernet, which field is actually added at the physical layer and is not part of the frame.
A
Preamble
B
CRC
C
Address
D
Location
ISRO CSE 2013   Computer Network
There are 10 questions to complete.

5 thoughts on “Physical Layer”

  1. Question no. 18 and Question no. 24 are same question but your answer is different.
    I Think answer is 218 please correct it.

    Reply

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