ds set 1

Q1.Multiple Choice Questions                                                                                             (20 Marks)

1) Which are examples of inherently distributed applications?

a) Computerised worldwide airline reservation system.                    b) Computerised banking system                                  c) Computerised factory automation system for controlling robots  d) All of these

2) Which of the following features is commonly not useful for distinguishing distributed OS and network OS

   a) System image            b) scalability                        c) Autonomy               d) Fault tolerance capability

3) For server locating, the advantage of binding agent mechanism is ______________

     a) To achieve degree of fault tolerance b) To balance server load c) To survive only authorised clients    d)All these

4) The system which can cope-up with the increased work load is called as____________

    a) Scalable               b) Transparent             c) Reliable                   d) Flexible

5) The interface definition helps RPC to ___________

a) Reduce data storage                                              b) Reduce the amount of data transferred over a network                                                            c) Generate appropriate calling sequence                  d) All

6) Which of the following property is needed for the resource sharing mechanism to provide concurrency transparency?

a) No starvation             b) No deadlock         c) Fault tolerance                      d) Both a) and b)

7) Which of the following design principles are useful for better reliability of the distributed systems?

  a) Fault tolerance          b) Fault detection   c) Minimize copying of data          d) Both a) and b)

8) Which technique is not used for implementing the fault detection and recovery method for improving reliability of distributing systems?

a) Atomic transaction         b) Stateless servers      c) Replication                d) None of these

9) What are the issues related to the correctness feature of good massage-passing systems?

     a) Atomicity                                b) User mobility                                    c)Survivability                            d) Both a) and b)

10) Which of the following is guiding principle for designing scalable distributed systems?   

        a) Minimize copying of data b) Avoid centralised algorithms   c) Minimize network traffic  d) None

11) In nonpreemptive process migration, a process is located ______________

   a) Before its start execution  b) During the course of its execution c) After its execution d) None

12) In the ordered-requests method for deadlock prevention if a process holds a resource  type whose number is i, it may request a resource type having the number j only if __________

   a) i > j                       b) i < j              c) j >= i          d) j <= i

13) The data-caching model offers possibility of increased performance & greater scalability because it reduces ___

     a) Network traffic    b) Contention for file servers   c) Copying of data   d) Both a) & b)

14) In process migration what is the advantage of “transfer on reference” address space transfer mechanism? 

            a) To reduce freezing time & thus causing minimal interference   b) It is simple & easy to implement                                        c) Reduce total time for process migration                                 d) Transfer pages on reference

15) What is the drawback of centralized approach for implementing mutual exclusion?

            a) It liable to single point of failure   b) Waiting time may be large if too many processes in the system                     c) Needs to detect failure of coordinator                     d) Both a) & c)

16) The UNIX emulation, what is the advantage of Chorus as compared to Mach?

   a) No modular design                       b) Non-protection    c) Poor system state management   d) Both a) & b)

17) The record level file transfer model is not suitable for use with ________

   a) Mutable file          b) Unstructured file     c) Structured file                      d) Both a) & b)

18) Which of the following is not the abstraction Chorus?

   a) Port                       b) Region                     c) Segment                               d) Task

19) In chorus OS which type of processes are privileged but not trusted?

     a) Kernel                 b) User                                       c) System                               d) None

20) Which component is not present in the system architecture of MACH

     a) Generic server                b) Supervisor               c) COOL subsystem                 d) Both b) & c)

2          Attempt any four:                                                                                                      

            a) What is distributed system? Differentiate between network operating system & distributed operating system.

            b) Explain threads in detail.

            c) Explain in detail desirable features of good message passing systems.

            d) Describe clock synchronisation.

            e) Explain event ordering.

3          What is group communication? Explain following with respect to one-to-many communication.       

a) Group addressing.    b) message delivery to receiver processes c) buffered and unbuffered multicast.

OR

Explain the distributed computing system models in details.

4          Explain failure handling in detail.                                                                                             

5          Attempt any four:                                                                                                          

            a) What is thread? Explain motivations for using threads.

b) Explain in detail process migration in heterogeneous systems.

c) Explain drifting of clocks.

            d) Explain a ring algorithm in detail.

            e) Explain different advantages of replication.

6          Attempt any one:                                                                                                                    

a) Explain Ricart Agrawala algorithm

b) Explain in detail design goals and system architecture of Log structured file system.

7          What are the different types of file sharing semantics?