OS

1.The file system permits users to create data collections, called files, with desirable properties, such as

***• Field, Record, File, Database

2.For terms are in common use when discussing files: ***• Field, Record, File, Database

3.What is a field? ***•It is the basic element of data

4.What is a record?***• It is a collection of related fields that can be treated as a unit by some application program

5.What is a file? ***•It is a collection of similar records.

6.In choosing a file organization, several criteria are important: ***• Short access time, Ease of update,

Economy of storage, Simple maintenance, Realibility

7.To understand the requirements for a file structure, it is helpful to consider the types of operations that may be performed on the directory: ***• Search, Delete, Create, List Directory, Update Directory

8.What is a Search? ***• When a user or application references a file, the directory must be searched to find the entry corresponding to that file.

9.What is a Create file? ***•When a new file is created, an entry must be added to the directory

10.What is a Delete file? ***• When a file is deleted, an entry must be removed from the directory

11.What is a List Directory? ***• All or a portion of the directory may be requested.

12.What is aUpdate Directory? ***• Because some file attributes are stored in the directory, a change in one of these attributes requires a change in the corresponding directory entry.

13.At the Secondary storage management what is a Volume? ***• A collection of addressable sectors in secondary memory that an OS or application can use for date storage

14.At the FILE SYSTEM SECURITY what is a Subject? ***• An entity capable of accessing objects

15.At the FILE SYSTEM SECURITY what is an Object? ***• Anything to which access is controlled

16.At the FILE SYSTEM SECURITY what is an Access right? ***• The way in which an object is accessed by a subject

17.At Linux Virtual File System Concept, The four primary object types in VFS are as follows: ***•

Superblock object, inode object, dentry object, file object

18.What is an EMBEDDED SYSTEMS? ***• combination of computer hardware and software, and perhaps additional mechanical or other part, designed to perform a dedicated function

19.CHARACTERISTICS OF EMBEDDED OPERATING SYSTEMS, Give definition to Real-time operation:

****• In many embedded systems, the correctness of a computation depends, in part, on the time at which it is delivered

20.Give the correct way to “Loading an eCos Configuration”: ***• GNU make utility>>Application source code>>GNU cross compiler>>GNU linker>>Executable file

21.Choose the correct choice of the “eCos Layered Structure” from bottomto- top? ***• Hardware abstraction layer, Kernel, I/O system, Standard C library, User application code

22.How many implemented separate modules has The HAL? ***• 3

23.How many main objectives has The eCos Kernel was designed to satisfy? ***• 4

24.What does “TINYOS” mean? ***• Represents a significant departure from other embedded operating systems

25.Three abstractions for resources are used in TinyOS: ***• Dedicated, Virtualized, Shared

26.What is a Computer Security? ****• The protection afforded to an automated information system in order to attain the applicable objectives of preserving the integrity, availability and confidentiality of information resources

27.This definition introduces three key objectives that are at the heart of computer security: ***•

Confidentiality, Integrity, Availability

28.Although the use of the CIA triad to define security objects is well established, some in the security field feel that additional concepts are needed to present a complete picture. Two of the most commonly mentioned are as follows: ***• Authenticity, Accountability

29.Network security attacks can be classified as: ***• Passive and active attacks

30.In an important early study of intrusion, Anderson[ANDE80] identified three classes of intruders:

****• Masquerader, misfeasor, clandestine user

31.What is a Virus? ****• Malware that, when executed, tries to replicate itself into other executable code

32.What is a Worm? ****• A computer program that can run independently and can propagate a complete working version of itself onto other hosts on a network

33.What is a Logic bomb? ****• A program inserted into software by an intruder

34.What is a Trojan horse? ****• A computer program that appears to have a useful function, but also has a hidden and potentially malicious function that evades security mechanisms, sometimes by exploiting legimate authorizations of a system entity that invokes the Trojan horse program

35.What is a Backdoor (trapdoor)? ****• Any mechanisms that bypasses a normal security check; it may allow unauthorized access to functionality

36.What is a Mobile code? ****• Software (e.g., script, macro, or other portable instruction) that can be shipped unchanged to a heterogeneous collection of platforms and execute with identical semantics

37.What is aExploits? ****• Code specific to a single vulnerability or set of vulnerabilities.

38.What is a Downloaders? ****• Program that installs other items on a machine that is under attack

39.What is an Auto-rooter? ****• Malicious hacker tools used to break into new machines remotely

40.What is a Kit (virus generator)? ****• Set of tools for generating new viruses automatically

41.What is a Spammer programs? ****• Used to send large volumes of unwanted e-mail.

42.What is a Flooders? ****• Used to attack networked computer systems with a large volume of traffic to carry out a denial-of-service (DoS) attack

43.What is a Keyloggers? *-***• Captures keystrokes on a compromised system

44.What is a Rootkit? ****• Set of hacker tools used after attacker has broken into a computer system and gained root-level access

45.What is a Zombie, bot? ****• Program activated on an infected machine that is activated to launch attacks on other machines

46.What is a Spyware? ****• Software that collects information from a computer and transmits it to another system

47.What is aAdware? ****• Advertising that is integrated into software

48. What is aInfection mechanism? ****• The means by which a virus spreads, enabling it to replicate

49.A virus classification by target includes the following categories,What is a File infector? *****•

Infects files that the operating system or shellconsider to be executable

50.What is a Multiplatform? ****• Newer worms are not limited to Windows machines but can attack a variety of platforms, especially the popular varieties of UNIX

51.Uses of Bots, What does mean Spamming ? ****• With the help of a botnet and thousands of bots, an attacker is ableto send massive amounts of bulk e-mail (spam)

52.A rootkitmaybe? ***** • Persistent, Memory based,User mode, Kernel mode

53.Memory based, rootkit? ******• Has no persistent code and therefore cannot survive a reboot

54.What is a Authentication? ***** • is the basis for mosttypes of access control and for user accountability

55.An authentication process consists of two steps: ***** • Identificationstep, Verificationstep

56.Among the potential drawbacks are the following [NIST95]: **** • Requires special reader, Token loss, User dissatisfaction

57.Access control policies are generally grouped into the following categories: ****** • Discretionary access control, Mandatory access control, Role-based access control

58.The following definitions from RFC 2828 (Internet Security Glossary) are relevant to our discussion: -

***** • Securityintrusion, Intrusiondetection

59.How many IDSs can be classified: ***** 5

60.IDSs can be classified as follows: ***** • Host-based IDS, Network-based IDS, Sensors, Analyzers, User interface

61.Malware Defense. Antivirus Approaches. The next best approach is to be able to do the following:

**** • Detection, Identification, Removal

62.If we say about Generic Decryption, what we are meaning of Virus signature scanner: **** • A module that scans the target code looking for known virus signatures

63.At Generic Client/Server Architecture (Client workstation) show correct way from bottom-to-top?

**** • Hardware platform, Client operating system, Communications software, Application logic,

Presentation services

64.[BREW97] lists four benefits that can be achieved with clustering. These can also be thought of as objectives or design requirements: ***** • Absolute scalability, Incremental scalability, High availability,

Superior price/performance

65.Parallelizing Computation, In some cases, effective use of a cluster requires executing software from a single application in parallel. [KAPP00] lists three general approaches to the problem: **** •

Parallelizing compiler, Parallelized application, Parametric computing

66.The Windows Cluster Server design makes use of the following concepts: *** • Cluster Service,

Resource, Online, Group

67.The major components of Sun Cluster are: ***** • Object and communication support, Process management, Networking, Global distributed file system

68.What is a Server? **** • is a computer program running to serve the requests of other programs, the "clients".

69.Show incorrect choice, when we mean types of Server: **** • Cooking server

70.The Sun Cluster networking subsystem has how many key elements? **** • 3

71.Which of the following is not a function of the CPU? **** • Processing video display data

73.Which of the following is not considered to be internal part of the computer? ****•

Communication device (network card, modem, etc)

74.Which of the following is an example of input-output device? **** • Network card

83. Which of the following is not a layer in OS design? **** • I/O level

84. What is the most obvious solution to low CPU utilization problem? **** • Multiprogramming

85. A processis **** • Instance of running program

86. Which of the following is not a principle of storage management responsibilities? ****• Process termination

87. Virtual memory takes advantage of **** • Large secondary memory

88. In a microkernel OS the scheduler resides in: ****• Kernel

89.Thread is: *** • Dispatchable unit of work

90.Which of the following cannot be interrupted? **** • Atomic operation

91.In Linux, the graphic subsystem is located in **** • User level

92.Which of the following is not considered to be a part of the process? *****• File structure

93.Trace of the process is: **** • List of instructions that are executed

94.Dispatcher is: **** • Small program which switches the processor from one process to another

95.The problem with two-state process model is **** • Single queue

96.Process spawning is **** • Creation of child process

99.Another term for spawning is: **** • Forking

100.File tables provide information about: ***** • Files, their location, status

101.Process control block consists of the following ***** • Process ID, state information, control information

102.Two modes of execution most processors support is: ***** • User mode and system mode

103.Which of the following is not a proper step in process creation? ***** • Clearing the memory

104.Which of the following is not a reason to switch a process? **** • Kernel update

105. Three types of operating system kernel process design: ***** • Separate kernel, OS functions within user processes, OS functions are separate processes

106.What thread approach did MS-DOS use? **** • One process, one thread

107.What thread approach does Java run-time environment use? **** • One process, multiple threads

108.What thread approach does Windows use? **** •Multiple processes, multiple threads per process

109.What controls the process in a single-threaded process model? ****• Process control block

112.Threadexecutionstatesare: ***** • Spawn, Block, Unblock, Finished

113.What relationship between threads and number of processes is used in old traditional UNIX implementations? ****** • One to one

114.What relationship between threads and number of processes is used Windows NT, OS/2, Solaris,

Linux? **** • Many to one

115.What relationship between threads and number of processes is used cloud computing? ***** • One to many

116.What relationship between threads and number of processes is used in TRIX systems? **** •

One to many

117.What type of parallel processor architecture is used in GPU (graphic cards) design? ***** • SIMD

123. A section of code within a process that requires access to shared resources and that must not be executed while another operation is in a corresponding section of code is called: **** • Critical section

124. A situation in which two or more processes are unable to proceed because each is waiting for one of the others to do something is called: ***** • Deadlock

125.A requirement that when one process is in a critical section that accesses shared resources no other operation may be in a critical section that accesses any of those shared resources is called: *****

• Mutual exclusion

126.A situation in which a runnable process is overlooked intinitely by the scheduler, although it is able

131.Which of the following is not one of the principles of dealing with deadlock? ***** • Initialization

132.Current allocation of resources to processes where there is at least one sequence that does not result in deadlock is called: ***** • Safe state

133.Current allocation of resources to processes where there is no sequence that does not result in deadlock is called: ***** • Unsafe state

134.Can you solve the Dining Philosophers’ Problem using monitors? ******• Yes

136.A fixed-length block of data in secondary memory is called: **** •Page

137.A variable-length block of data that resides in secondary memory is called: **** • Segment

139.Memory partitioning algorithm that uses binary tree as a data structure is called: **** • Buddy system

140.A state in which the system spends most of its time swapping pieces rather than executing

153. Convert this number systems: OCT(6512) to DEC? ***** • 3402

154. Convert this number systems: OCT(5614) to DEC? ****• 2956

155.Convert this number systems: OCT(7745) to DEC? *****• 4069

156.Convert this number systems: OCT(6734) to DEC? *****• 3548

168.Convert this number systems: DEC(8134) to HEX?: -*-***•1FC6

169.Convert this number systems: DEC(9123) to HEX?: *****• 23A3

183.How many parts of Memory Hierarchy? ***** 3

184.In Memory Hierarchy, at the Outboard storage which of the following are included: ****• Magnetic

disk

185. In Memory Hierarchy, at the Off-line storage which of the following are included: ****• Magnetic tape

186.In Memory Hierarchy, at the Inboard memory which of the following are included: *****•Main memory

187.Cache Design has these properties? ****• Size, block size, mapping function, replacement algorithm, write policy

191.Much of the work in security and protection as it relates to operating systems can be roughly grouped into four categories? **** • Availability, confidentiality, data integrity, authenticity

192.The central themes of operating system design are all concerned with the management of processes and threads? **** • Multiprogramming, multiprocessing, distributed processing