250+ TOP MCQs on I/O Subsystem and Answers

Operating System Multiple Choice Questions on “I/O Subsystem”.

1. I/O hardware contains ____________
a) Bus
b) Controller
c) I/O port and its registers
d) All of the mentioned

Answer: d
Clarification: None.

2. The data-in register of I/O port is ____________
a) Read by host to get input
b) Read by controller to get input
c) Written by host to send output
d) Written by host to start a command

Answer: a
Clarification: None.

3. The host sets _____ bit when a command is available for the controller to execute.
a) write
b) status
c) command-ready
d) control

Answer: c
Clarification: None.

4. When hardware is accessed by reading and writing to the specific memory locations, then it is called ____________
a) port-mapped I/O
b) controller-mapped I/O
c) bus-mapped I/O
d) none of the mentioned

Answer: d
Clarification: It is called memory-mapped I/O.

5. Device drivers are implemented to interface ____________
a) character devices
b) block devices
c) network devices
d) all of the mentioned

Answer: d
Clarification: None.

6. Which hardware triggers some operation after certain programmed count?
a) programmable interval timer
b) interrupt timer
c) programmable timer
d) none of the mentioned

Answer: a
Clarification: None.

7. The device-status table contains ____________
a) each I/O device type
b) each I/O device address
c) each I/O device state
d) all of the mentioned

Answer: d
Clarification: None.

8. Which buffer holds the output for a device?
a) spool
b) output
c) status
d) magic

Answer: a
Clarification: None.

9. Which one of the following connects high-speed high-bandwidth device to memory subsystem and CPU.
a) Expansion bus
b) PCI bus
c) SCSI bus
d) None of the mentioned

Answer: a
Clarification: None.

10. A process is moved to wait queue when I/O request is made with ____________
a) non-blocking I/O
b) blocking I/O
c) asynchronous I/O
d) synchronous I/O

Answer: b

250+ TOP MCQs on Distributed Operating System – Robustness of Distributed Systems

Operating System Multiple Choice Questions on “Robustness of Distributed Systems”.

1. How many layers does the Internet model ISO consist of?
a) Three
b) Five
c) Seven
d) Eight

Answer: c

2. Which layer is responsible for The process-to-process delivery?
a) Network
b) Transport
c) Application
d) Physical

Answer: b
Clarification: None.

3. Which layer is the layer closest to the transmission medium?
a) Physical
b) Data link
c) Network
d) Transport

Answer: a
Clarification: None.

4. Header are ______ when data packet moves from upper to the lower layers?
a) Modified
b) Removed
c) Added
d) All of the mentioned

Answer: c
Clarification: None.

5. Which layer lies between the transport layer and data link layer?
a) Physical
b) Network
c) Application
d) Session

Answer: b
Clarification: None.

6. Which of the following is an application layer service?
a) Mail service
b) File transfer
c) Remote access
d) All of the mentioned

Answer: d
Clarification: None.

7. What are the different ways distributed may suffer?
a) Failure of a link
b) Failure of a site
c) Loss of message
d) All of the mentioned

Answer: d
Clarification: None.

8. What are design issues in distributed system structure?
a) Scalability
b) Fault-tolerance
c) Clustering
d) All of the mentioned

Answer: d
Clarification: None.

9. In which OSI layer encryption and decryption happens?
a) Application
b) Presentation
c) Transport
d) Data Link

Answer: b
Clarification: None.

10. What are the important steps followed when recovery from failure happens?
a) Post repairing integration with main system should happen smoothly and gracefully
b) Upon link failure both parties at end must not be notified
c) Fault recovery system must me adjusted
d) Failures are logged systematically

Answer: a