ds set2

Q1.Multiple Choice Questions                                                                                  

1) The ability of a system to continue functioning in the event of partial system failure is

     a) Fault Tolerance   b) Fault Avoidance      c) Fault Recovery        d) Fault Detection

2) The workstation model is a network of personal workstations, each with its own disk and a local file system

     a) True        b) False

3) A_______is a block of information formatted by a sending process in such a manner that it is meaningful to the receiving process.

     a) File         b) Directory                 c) Message                   d) Disk Storage           

4) _________ensures that every message sent to a group of receivers will be delivered to either all of them or none of them.

   a) Consistency          b) Isolation      c) Durability                d) Atomicity

5) A___________distributed system consists of interconnected sets of dissimilar hardware or software systems.

   a) Heterogeneous                  b) Homogeneous                     c) Ecosystem               d) none of above

6) If two message sending events are said to be causally related if they are correlated by the____________

     a) Happened before relation      b) Causal relation  c) Happened after relation       d) All the above

7) RPCs consumes much more time___________than local procedure calls

     a) 10 -100 times more     b) 100 – 1000 times more     c) 1 – 10 times more      d) none of above.

8) A________server generally remains in existence indefinitely

    a) non-persistent      b) persistent     c) 1- persistent             d) 0-persistent

9) A client is bound to a server at the time when it calls the server for the first time during its execution is called as

   a) binding at link time           b) binding at  call time             c) binding at compile time       d) none of above.

10) __________deals with fine grained parallelism for better utilization of the processing capacity of the system

   a) process                 b) threads                     c) process migration                 d) none of above.

11)The process by which the client becomes associated with the server so that calls can takes place is known as ___

     a) Naming               b) Binding agent          c) both a and b                                     d) binding

12) Two commonly used mutual exclusion techniques in a threads package are______and_______

     a) critical region and conditional variables              b) conditional variable and segment of code     

     c) mutex variables and conditional variables          d) None of these         

13) The process of converting from a particular machine representation to external data representation format is called_

    a) deserializing         b) serializing                c) non-serializing                     d) none of above

14) In ______ clock synchronization algorithms one node has a real time receiver

    a) centralized                       b) decentralized                       c) distributed                            d) none of above

15) A computer clock usually consists of three components a quartz crystal a counter register and ____

   a) constant register    b) state register             c) oscillator                  d) none of above

16) In _____ method each source type is assigned a unique global number to impose a total ordering of all resource types

     a) collective request                        b) ordered request                    c) preemption              d)non-preemption

17) The ____ model attempts to reduce the amount of network traffic by taking advantage of the locally feature found in file accesses

     a) client-server                    b) remote-service                     c) data-caching                                    d) none of above

18) Which port is created by a memory manager?

     a) name port                   b)control port    c) both a and b   d) object port

19) A user should not be forced to work on a specific node but should have the flexibility to work on different nodes at different times is called as_____________

a) Performance                  b) simplicity                 c) scalability                d) user mobility

20) Mach provides an interface generator called_______

a) Mach interface generator           b) Mach generator interface     c) Mach gateway interface       d)None of the above

2          Attempt any four:                                                                            (5x4=20 Marks)

            a) Explain how the Distributed Operating System is different from the Network Operating System

            b) Explain the scalability issue in designing of the distributed operating systems

            c) What is the message passing system? Explain the correctness feature of the good message passing system.

            d) Explain need of process migration.

e) Explain with example how to keep track of lost and out of sequence packets in a multidatagram message transmission.

3          Attempt any one:                                                                                          10 Marks

            a) Explain the different models in the design of the distributed computing systems

b) Explain the following with respect to the one-to-many communication

i) Group communication          ii) Flexible reliability in multicast communication

4          List election algorithms and explain any one.                                                              10 Marks

5          Attempt any four:                                                                                              (5x4=20 Marks)

            a) What is freezing time? Explain the handling of coprocesses in process migration mechanism.

            b) Explain with example the Berkeley algorithm for clock synchronization.

            c) Explain the Distributed mutual exclusion algorithm with example

            d) Explain the immutable file sharing and the session semantics in distributed file systems.

            e) Note on memory coherence.

6          Attempt any one:                                                                                                     10Marks

a) Explain in detail the file caching scheme in Distributed File Systems.

b) Explain in detail the different methods of address-space transfer mechanism in process migration.

 7         Explain token based and non token based algorithms in distributed mutual exclusion.