Get premium membership and access revision papers, questions with answers as well as video lessons.

Comp 464: Distributed Systems Question Paper

Comp 464: Distributed Systems 

Course:Bachelor Of Education Arts

Institution: Kabarak University question papers

Exam Year:2011



INSTRUCTIONS:
Answer ALL Questions in Section A, TWO Questions in Section B

SECTION A:
1.
a) With examples describe Access, Location and Migration transparency
in a distributed system. (3 marks)

b) What are Client and Server Stubs and how are they used in remote
procedure calls? (3 mark)

c) What is a distributed system? (1 mark)

d) Explain the meaning of the following terms and give examples where appropriate:

(i) Middleware (1 mark)
(ii) Persistent & Transient objects (1 mark)
(iii) Message Oriented Middleware(MOM) (2 mark)
(iv) Logical clock (1 mark)

e) Explain with examples the difference between a name server and
a directory server. (2 marks)

f) With examples illustrate the difference between passive and active
replication. (4 marks)
g) Explain the advantages of distributed systems over centralized systems.
(4 marks)
h) Define what it means for an interleaving of two transactions to be
serially equivalent? (2 marks)

i). With examples explain the difference between iterative name resolution
and recursive name resolution. (3 marks)
j).Why is the two-phase commit algorithm used in distributed transactions?
(2 marks)
k).Explain RPC in distributed system (2 marks)


SECTION B

2.
a). what is client server model? (1 marks)

b). Explain reasons for distribution in a distributed system. (4 marks)

c). Explain the levels in the client server model (4 marks)

d). Define Inter process communication (IPC) (1 mark)

e). What is communication protocol? (1 mark)

f). Explain the following citing example in each case:

a).connection- oriented communication service (2marks)
b).connectionless communication service (2 marks)

g). Explain the disadvantages of distributed systems (5 marks)

3.
a). Discuss all levels of transparency in a distributed system (5 marks)

b).Why does naming systems play an important role in a distributed environment?
(3 marks)
c). Explain the meaning of the following terms in relation to naming:

i). Entity (1 mark)
ii).Identifier (1 mark)
iii).Address (1 mark)
iv).Name (1 mark)

d). Explain in detail the Bully algorithm for electing a leader. (6 marks)

e).State categories of clock synchronization algorithms citing examples in each case.
(2 marks)
4.
a). Discuss performance and scalability in a distributed system (4 marks)

b). what is strict consistency and why is not possible to achieve in a
distributed system? (3 marks)
c). Define Failure? (1 mark)

d). Explain types of faults in distributed environment (3 marks)

e). Explain what problems can happen when there is no concurrency control
where multiple transactions are being executed at the same time. (3 marks)

f). What is redundancy and explain its types and why is it used in a distributed
system. (3 marks)

g).Discuss security in distributed systems (3 marks)






More Question Papers


Popular Exams



Return to Question Papers