# 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 1 Explanation:
 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 2 Explanation:
 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 3 Explanation:
 Question 4
Physical topology of FDDI is?
 A Bus B Ring C Star D None of the above
ISRO CSE 2017   Computer Network
Question 4 Explanation:
 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 5 Explanation:
 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 6 Explanation:
 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 7 Explanation:
 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 8 Explanation:
 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 9 Explanation:
 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
Question 10 Explanation:
There are 10 questions to complete.

### 5 thoughts on “Physical Layer”

1. Question no. 14 your answer not match with gate overflow solution.

• Thank you dp kushwaha,