D G193009 Pages:2

Reg No.:_ Name:

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
SEVENTH SEMESTER B.TECH DEGREE EXAMINATION(R&S), MARCH 2020

Course Code: CS407
Course Name: DISTRIBUTED COMPUTING

Max. Marks: 100 Duration: 3 Hours
PARTA

Answer all questions, each carries 4 marks. Marks
1 Define mobile agents. How this will create security threats. (4)
2 Outline the layered and tiered architectural patterns used in distributed systems. (4)
3 Distinguish between the two variants of the interaction model in distributed (4)

systems.

4 Explain the three RPC call semantics. (4)
5 What is file group? How will you generate a unique identifier for a file group? (4)
6 Explain the mount service in NFS. (4)
7 Suppose that there are 100 items currently in a stock. Given two transactions U (4)

and V as below. Explain the inconsistent retrievals problem in this scenario and

propose a solution for that.

Purchase 200 items Read item count in Stock
Sell 50 items
8 Explain two version locking. (4)
9 Define mutual exclusion and summarize its three essential requirements. (4)
10 Evaluate the performance of Maekawa’s voting algorithm. (4)
PART छ

Answer any two full questions, each carries 9 marks.
11 a) “The absence of these two transparencies most strongly affects the utilization of (4)
distributed resources”. Identify and explain the above two types of

transparencies with examples.

b) Compare workstation model with workstation-server model. (5)
12 a) Distinguish between mobile computing and ubiquitous computing. (4)
b) Compare client-server architecture with peer to peer architecture. (5)
13 a) Distinguish between Omission Failures and Arbitrary failures. (4)

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