Philadelphia University
Faculty of Information Technology
Lecturer
: Dr. M. Maouche
Coordinator
: Dr M. Maouche
Internal Examiner : Dr N. Nedam
Marking Schema
Department of Computer Science
Course Name: Advanced OS (750434)
Section: 1
First Exam
First Semester Academic Year: 2014/15
Question1: (8 marks)
Date: November, 19th, 2014
Time: 60 minutes
1. Point to point link (1); multipoint slink (1)
2. (0.5 x 4)
Access transparency,
Location transparency, Replication transparency,
concurrency transparency,....
3. A cient process is a process that requests services (1) while a process server is a
process that delivers services (1)
4. Describe briefly two different ways to design OS kernels. (2 marks)
-Monolithic kernel: a whole and large component that implements all needed system
functions/services (1)
- Micro-kernel: a small and simple component that implements only the basic an
primitive systems functions (10
Question2: (5 marks)
0-3 :
7
4-7 :
Moha
8-11:
mad x
12-15: 1999
16-19: 4
20-23: 1
24-27: A
28-31: 1
32-35: C
36-39: 1
40-43: A
44-47: 1
48-51: B
String field (2); integer field (1); sequence field (2)
Question3 : (6 marks)
1. xxx:
message identifier
(xxx: number)
00:
request type
yy: client identifier
(yy: number)
zz: identifier of the program that delivers the increment operation
(zz: number)
vv: version of the program
(vv: number)
cc: code of the increment operation
vvvv: value of the integer (parameter of the operation increment)
General structure of the message (1); message content (1)
2. xxx:
11:
00:
message identifier
reply type
successful
(xxx: number)
General structure of the message (1); message content (1)
3. Increment operation is not idempotent (1) because if it is executed twice ore more
times the value of the variable n will be changed at each call of the operation (1)
Question4 : (4 marks)
void do_something(int x,char* str) {
construct_message;
send_message_over_net;
wait_and_unpack_reply;
return_answer;
}