Computer Science and Information Technology - Computer Network
Exam Duration: 45 Mins Total Questions : 30
A channel has propagation delay of 10 s. For 320 bits frame, what will be the channel bit rate of stop-and-wait give efficiency of 50% ?
- (a)
80 byte/s
- (b)
110 byte/s
- (c)
16 byte/s
- (d)
320 byte/s
Process -to process delivery is related to
- (a)
data link layer
- (b)
network layer
- (c)
transport layer
- (d)
None of these
Which of the following addresses cannot be changed?
- (a)
Hardware address
- (b)
Logical address
- (c)
Both (a) and (b)
- (d)
None of these
Port number is
- (a)
process number
- (b)
computer's physical address
- (c)
Both (a) and (b)
- (d)
None of the above
The Internet Protocol (IP) generally corresponds to OSi layer
- (a)
network layer
- (b)
transport
- (c)
data link
- (d)
session
Which of the following devices primarily function at OSI network layer?
- (a)
Switch
- (b)
Gateway
- (c)
Router
- (d)
All of these
What type of network topology is depicted by a single cable, where devices connected using T connector?
- (a)
Star
- (b)
Bus
- (c)
Ring
- (d)
10 Base T
Which of the following error detection methods uses ones complement arithmetic?
- (a)
Aimple parity check
- (b)
Hamming code
- (c)
CRC
- (d)
checksum
Start and stop bits are used in serial communication for
- (a)
error detection
- (b)
error correction
- (c)
synchronization
- (d)
slowing down the communication
A sender sends a series of packets to the same destination using 5 bit sequence numbers. If the sequence number states with 0 what is the sequence
number after sending 100 packets?
- (a)
2
- (b)
3
- (c)
4
- (d)
5
IP has
- (a)
flow control machenism
- (b)
congestion control machenism
- (c)
Both (a) and (b)
- (d)
None of the above
Which of the following is not a function of TCP?
- (a)
Binding physical address to IP address
- (b)
Reassembling segments
- (c)
Acknowledge receipt of segments
- (d)
Re-transmission of segments
In a ...........attack, an intruder comes between two communicating parties, intercepting and re-playing to their message.
- (a)
return
- (b)
man-in-the middle
- (c)
replay
- (d)
bucket-bridge
Which of the following is not a field in the ethernet message packet ?
- (a)
Type
- (b)
Data
- (c)
Pin code
- (d)
Address
Match the following
List I | List II |
A. Data link layer | 1. The lowest layer whose function is to activate, deactivate and maintain the circuit between DTE and DCE |
B. Physical layer | 2. Performs routing and communication |
C. Presentation layer | 3. Detection and recovery from errors in the transmitted data. |
D. Network layer | 4. Concerned with for the syntax of the data |
- (a)
A B C D 3 1 4 2 - (b)
A B C D 2 1 4 3 - (c)
A B C D 4 1 2 3 - (d)
A B C D 2 1 3 4
A device that can convert digital signals to analog signals is
- (a)
a packet
- (b)
a modem
- (c)
an emulator
- (d)
None of these
A network that requires human intervention to route signals is called a
- (a)
bus network
- (b)
ring network
- (c)
star network
- (d)
T-switched network
A T-switched is used to
- (a)
control how messages are passed between computers
- (b)
echo every character that is received
- (c)
by transmit characters one at a time
- (d)
rearrange the connections between computing equipments
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 MHz
Baseband is
- (a)
transmission of signals without modulation
- (b)
a signal all of whose energy is contained within a finite a frequency range
- (c)
the simultaneous transmission of data to a number of stations
- (d)
All of the above
Satellite switched Time-Division Multiple Access (SS/TDMA) is
- (a)
the method of determining which device has access to the transmission medium at any time
- (b)
a medium access control technique for multiple access transmission media
- (c)
a form of TDMA in which act switching is used to dynamically change the channel assignments
- (d)
All of the above
A bridge can
- (a)
filter a frame
- (b)
forward a frame
- (c)
extend a LAN
- (d)
All of these
At which layer of the OSI model the router configuration problem resides ?
- (a)
Transport
- (b)
Network
- (c)
Logical Link
- (d)
Physical
Non-polling system is
- (a)
TDMA
- (b)
stop-and-wait
- (c)
continuous ARQ
- (d)
None of these
Which of the following is the characteristic of packet switching ?
- (a)
Each packet should contain addressing information
- (b)
For a best effort delivary service a connection set-up phase is not required
- (c)
Packets can be of arbitrary length
- (d)
All of the above
Which IP class provides the fewest numbers of hosts ?
- (a)
Class A
- (b)
Class B
- (c)
Class C
- (d)
Class D
Match List I (Function) with List II (Layer) and select the correct answer using the codes given below the lists.
List I | List II |
A. Route determination | 1. Data link |
B. Packet switvh | 2. Network layer |
C. Flow control | 3. Transport layer |
- (a)
A B C 2 2 3 - (b)
A B C 1 2 1 - (c)
A B C 2 2 1 - (d)
A B C 2 2 1,3
Match List I (Function) with List II and select the correct answer using the codes given below the lists.
LIst I | List II |
A. Reassembly packets | 1. Transport |
B. Responsibility for delivery between adjacent nodes | 2. Data link |
C. Mechanical electrical and functional interface | 3. Physical |
D. Error connection and re-transmission |
- (a)
A B C D 1 2 3 4 - (b)
A B C D 1 3 2 2 - (c)
A B C D 1 1 3 2 - (d)
A B C D 1 2 3 1,2
A subnet mask n class A fourteen 1's. How many subnet does it define ?
- (a)
32
- (b)
8
- (c)
64
- (d)
128
Two station A and B are connected via a point-to-point link and exchange frames both employing the go-back-n sliding window protocol with window size 7. Sequence number is of 3 bits.
Station A sends frames 0 through 6. Station B receives them in order. Station B sends 1 data frame to A (which A receives currently) after receiving 4 but before receiving frame 5. What will be the buffer frames in the current window of A ?
- (a)
4, 5, 6, 7, 0, 1, 2
- (b)
6, 7, 0, 1, 2, 3, 4
- (c)
5, 6, 7, 0, 1, 2, 3
- (d)
3, 4, 5, 6, 7, 0, 1