DISTRIBUTED SYSTEMS ANNAUNIVERSITY PREVIOUS QUESTION PAPER

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2009.

Seventh Semester
Information Technology
IT1001- DISTRIBUTED SYSTEMS
(Regulation 2004)

Time: Three hours Maximum:100 marks

Answer ALL questions.

PART A- (10 X 2= 20 marks)

1. What is the main objective of distributed systems? What are the challenges?

2. What is the need for IDL?

3. Name the paradigms for distributed programming.

4. What is RAID?

5. What are the requirements for distributed mutual exclusion algorithms?

6. What is null RPC?

7. What are hierarchic locks?

8. What are phantom deadlocks?

9. What are trap door functions?

10. What is a linearizable service?


PART B - (5 X 16= 80 marks)

11. (a) (i) Describe the architectural models of distributed systems.(Marks 8)

(ii) What is marshalling? What are the different approaches of external data representation? Discuss.(Marks 8)
(Or)
(b) (i) Describe the various RPC protocols supporting client server communication.(Marks 10)

(ii) How is IPC implemented in UNIX? Explain.(Marks 6)

12. (a) How does the communication between distributed objects take place? Describe the related issues.(Marks 16)
(Or)

(b) What is name service? What are its goals? How is it implemented? What is directory service?(Marks 16)

13. (a) Describe the architecture for multi threaded servers. Discuss the issues related to thread programming, thread lifetime, thread synchronization, scheduling and implementation.(Marks 16)
(Or)

(b) (i) What is the significance of time in distributed system? What are the ways for synchronizing clocks? Give brief overview of various techniques. (Marks 8)

(ii) What do you understand by logical time and logical clocks? What is lamport's contribution for it? Discuss.(Marks 8)

14. (a) Discuss the various concurrency control protocols.(Marks 16)
(Or)

(b) Describe the various deadlock handling techniques.(Marks 16)

15. (a) Elaborate on various cryptographic algorithms. (Marks 16)
(Or)

(b) Write notes on:
(i) Fault tolerant services.(Marks 8)

(ii) Highly available services.(Marks 8)