Fundamentals of Computer

ent overwhelmrogation root Fundamentals of Computer IIBM Institute of Business focussing Semester-I Examination Paper MM. 100 Fundamentals of Computer Section A accusatory Type (20 marks) ********************************************************** Multiple Choices 1. b. 2 types 2. b. 1 or more excitant signals to produce production 3. d. Both (a) & (c) 4. b. Non-volatile 5. c. Direct- irritate storage device 6. c. Multiple reject course of instruction accuses of any softwargon 7. a. Are geographic ally distributed 8. b. Way in which the ne tworks nodes be linked together 9. a. World huge web 10. . General advise electronic equipment for homes Fill in the Blanks 1. multimedia governing body applications be multimedia presentation, foreign speech keep an eye oning, multimedia Kiosk and multimedia books, e books, digital library, scene games, animation films & practical(prenominal) shops 2. Computer audio recording deals with synthesizing, recording and Palying audio with a figurer. 3. Collating sequence is ordering of symbols in an encode. standard. 4. Binary coded decimal is a 6-Bit Code. 5. The logic gates ar incorporate to form gating or logic net kit and boodle known as combinational.. ogic circuits. 6. mainframe calculation machine. is the brain of a entropy processor system. 7. The term bundle. refers to a allurement of programs. 8. Program errors ar known as bugs 9. Documentation. is the process of collecting, organizing storing and maintaining a complete historical record of programs. 10. read ecesis deals with physical organization of records of a shoot for convenience of their storage and retrieval. Section B wretchedstop Questions (20 marks) 1. What is entropy bear on? Data process is a series of effects on input that converts the input into useful rig.In data processing, input is data and output is the useful information. In consists of three sub activities Capturing input data, manipulating it and produc ing output information. People, mapping and devices are required to produce the output from the input data. 2. What is a show management system? File management system is a luck of programs which help the exploiters to organize, become, delete, update and manipulate their files. Its common features are as describe below. a. Trans execution file It stores the input data until the application uses it during next processing cycle. b.Master file It acquits all current data relevant to an application. c. Output file some applications use multiple programs. mavin program takes the output of some other program as input hence the former program stores the output as an output file. d. Report file It is a copy of report, generated by application in calculating machine chafeible form. e. Backup file It is a copy of file crated by drug user or system to deflect loss of data due to corruption or deletion of professional file. 3. What is a calculator network? Computer network is a c ollection of computers which are linked to each other via internet.The computers on network thunder mug communicate with each other and apprise share information. Four basic service countenanced by internet to its users are electronic mail, file de exculpated protocol, telnet and use net news. The common network types are personal field of operation networks (PANs), local welkin networks (LANs), metropolitan area network (MANs), campus area networks (CANs) and all-embracing area network (WANs). 4. What is a secondary storage? The lenditional storehouse needed in all computers to oercome the limitations of primary storage (Limited depicted object and Volatile) is called secondary storage. t is nonvolatile and has lower cost per bit stored. It operates slackly at slower speed than primary storage. Computer system uses it earlier to store large volume of data on permanent basis. unremarkably used storage devices are hard disk, CD ROM, DVD, stock visiting card and Pen bugger off. Section C Long Questions (20 marks) 1. Explain the put outing fulfill of laser news composingman. Mechanism of Laser Printers Transfer of Data The very introductory step in laser printing is the transfer of data from a computer to the memory of the image processor of a newspaperwoman. Writing DataNow, unmatched time the data is transferred to the printers memory, it is indite to the printers drum with the help of a laser. The drum give keep rotating and the act it rotates past the laser, it sweeps off the printers surface neutralizing some espy to about -100v. These spots are the areas where the toner remains stuck to the drum and further gets transferred to the authorship. Inserting the Paper and Pickup Process of the Toner Once the writing process is over, you need to add papers to the printer. Keep the papers into the printers paper tray.The feed rollers inside the printer pull the paper inside and the registration rollers hold it till its pocket. As the drum keeps on rotating, the toner settles raven in an area which is at a institutionalize of about -100v and remains attached to the drum till the paper comes in. Transfer of the Toner to the Paper Now, the complete toned image is created on the drum. The moment you apply the paper to the printer, the toner transfer process starts. The transfer corona applies a charge of about +600v to the paper and when the paper passes through the drum, the toner which is at a charge of about -100v gets transferred to the paper.Further, the paper passes through a static charge eliminator that decreases the positive charge in the paper, with the help of its negative charge. Fusing The process of nuclear fusion takes place in order to secure the printout by melting the flake plastic fragments present on the toners surface, so as to fix them to the paper fibers. Laser printers are handy when it comes to fast, bulk and quality printing. still advanced prices and some health risks much(prenomi nal)(prenominal) as respiratory disorders due to the release of some harmful sub-micrometer particles are some of the disadvantages associated with laser printing.However, this kind of printer still remains the for the startle time choice for or so of the organizations when it comes to printing. 2. Explain the enormousness of system software for a computer system. schema Software is a set of programs that manage the resources of a compute system. System Software is a collection of system programs that perform a variety of functions. * File modify * Resource Accounting * I/O Management * Storage, Memory Management access management. System Software grass be broadly class into three types as System control programs It tick offs the execution of programs, anage the storage & processing resources of the computer & perform other management & monitoring function. The most of the essence(p) of these programs is the in operation(p) system. Other examples are database management s ystems (DBMS) & communication monitors. System gestate programs It provide routine service functions to the other computer programs & computer users E. g. Utilities, libraries, motion monitors & job accounting. System development programs assists in the creation of application programs. E. g. , phrase translators such as BASIC interpreter & application generators.Application Software It performs specialized tasks for the computer user. Application software is a program which program written for, or, by, a user to perform a particular job. Languages already address equal for microcomputers include Clout, Q & A and Savvy ret rival. The use of natural language touches on expert systems, computerized collections of the knowledge of many gracious experts in a given field, and artificial intelligence, independently smart computer systems two topics that are receiving much attention and development and will continue to do so in the future. 1.Operating System Software Storage theat re director Process Manager File System Manager I/O Control System Communication Manager 2. Standard System Software Language commutation processor Loaders Software Tools 3. Application Software Sort/Merge Package paysheet/Accounting Package DBMS General-purpose application software such as electronic spreadsheet has a ample variety of applications. Specific purpose application s/w such as payroll & gross revenue analysis is used for the application for which it is designed. Section D Applied surmisal (40 marks) 1. What is a computer computer virus? How does a typical virus works?When a computer system suffers from virus transmittal, how it is cured? Defenition Computer virus is a small software programs that are designed by human to spread from one computer to another(prenominal) and to interfere with normal computer operations. Work of Typical virus The A computer virus is most often defined as a malicious code of computer programming. What this means is that a computer vi rus is just another software, written with not so very noble intentions. A computer virus is designed to install, propagate and cause damage to computer files and data without the knowledge and/or express consent of the user.A computer virus derriere only survive, attack and propagate in computer memory. Computer memory is usually the RAM (and all varied variations of it) and disk storage (hard, floppy and everything in in the midst of). overly this you will not find computer viruses in your monitor, keyboard and certainly not in your own blood stream The first step in any virus attack is al focal points the invasion. This is when the virus actually enters the computer system from an outside source. Much of the effort in preventing a virus attack lies in understanding what these virus immersion points are and how best to monitor and block out any doable intrusion.All viruses enter the computer system through two main entre points the disk network adapter card is most likely your computer network and/or modem card connected to the local Intranet and/or the Internet. virus enters through the network card most likely disguised in the form of attachments in e-mails. These attachments are often program files and office documents containing macros. Besides this, certain webpages that we visit on the Internet whitethorn also contain harmful programming codes that might transfer virus or virus-like codes into our system.To reserve our systems against virus intrusion from these sources, many good anti-virus programs allows users to completely s dissolve all files read form disk drives or downloaded from the Intranet/Internet. How do virus infections fleet? The act of infection often begins with a harmless looking action such as opening a file (like a video game or a Word document) that one often gets in e-mail attachments or while accessing any disk in a disk drive. These actions inadvertently activate the virus lurking in these files and disks. The virus then(prenominal) installs itself into the computers memory. Computer system suffering from virus infection after(prenominal) entering the computer memory, a virus often today sets out to multiply and spread duplicate copies of itself across the main data storage device (most often the hard disk drive). It does this by write itself into as many files it hind end find on the disk drive. later when users transfers or copies these files to their friends and colleagues, the virus gain entry into ever increasing act of systems. If the virus has found its way to this level of the users computer, the user plumps a high risk of permanent damage to data and hardware. But such a level of infection only happens to two types of users.The first are those who do not employ any kind of anti-virus measures (or if they do, it evidently isnt doing a good job). The second are those who do use up good anti-virus programs installed and running but did not bother updating their software with the l atest virus data files. As a result newer viruses can actually use the anti-virus programs to infect an even greater enactment of files. So we can see here that having good anti-virus software isnt enough. One must constantly keep it updated (preferably on a monthly basis). If a virus were to just spread itself, users might not have much to worry about.But the worst is yet to come. Many viruses contain what is called a payload. This is the crushing sequence that is activated on a certain trigger. The trigger may be the arrival of a particular date or an action done by the user. The effect of the payload can be anything as benign as some harmless message appearing on screen to as frightening as the destruction of the disk drives boot record making it completely unusable and in most cases completely irreparable. Indeed it is the later that causes permanent lose of data and hardware and which is answerable for the virus notorious reputation.If a virus is undefended of unleashing i ts payload on the users system, this indicates a serious discontinue of security on part of the user. Its time for the user to learn from the experience and never let computer virus have a second chance. How do I know if my computer has been infected? After you open and run an infected program or attachment on your computer, you might not realize that youve introduced a virus until you notice something isnt sort of right. Here are a few indicators that your computermightbe infected * Your computer runs more slowly than normal * Your computer lucre responding or freezes often Your computer crashes and restarts every few minutes * Your computer restarts on its own and then fails to run normally * Applications on your computer dont work correctly * Disks or disk drives are inaccessible * You cant print correctly * You see unusual error messages * You see distorted menus and dialogue boxes How to Cure Remove a virus manually Sometimes a virus must be removed manually. This can becom e a technical process that you should only undertake if you have experience with theWindowsregistry and know how to view and delete system and program files inWindows.First, some(prenominal)ise the virus by name by running your antivirus program. If you dont have an antivirus program or if your program doesnt detect the virus, you might still be able to identify it by looking for clues about how it behaves. Write down the row in any messages it displays or, if you received the virus in email, write down the subject line or name of the file attached to the message. then(prenominal) search an antivirus vendors website for references to what you wrote down to try to find the name of the virus and instruction manual for how to remove it. Recovery and preventionAfter the virus is removed, you might need to reinstall some software or restore lost information. Doing unwavering backups on your files can help you avoid data loss if your computer becomes infected again. If you havent ke pt backups in the past, we recommend that you start now. 3. Write short notes on (a) The OSI stumper (b) Internetworking tools (c) Distributed reckoning systems (a) The OSI model The Open System Interconnection, model defines a networking framework to implement protocols in seven shapes. This article explains the 7 moulds of the OSI Model.TheOSI, orOpenSystemInterconnection, model defines a networking framework to implement protocols in seven grades. Control is passed from one layer to the next, starting at the application layer in one station, and proceeding to the bottom layer, over the channel to the next station and back up the hierarchy. a. Application Layer This layer supportsapplicationand end-user processes. Communication partners are identified, quality of service is identified, user authentication and privacy are pick outed, and any constraints on data sentence structureare identified.Everything at this layer is application-specific. This layer provides application go forfile transfers,e-mail, and othernetworksoftwareservices. TelnetandFTPare applications that exist but in the application level. Tiered application architectures are part of this layer. b. institution Layer This layer provides independence from differences in data representation (e. g. ,encryption) by translating from application to network format, and vice versa. The presentation layer works to commute data into the form that the application layer can accept.This layer formats and encrypts data to be sent across anetwork, providing freedom from compatibility problems. It is sometimes called the sentence structure layer. c. Session Layer This layer establishes, manages and terminates connections betweenapplications. The session layer sets up, coordinates, and terminates conversations, ex removes, and dialogues between the applications at each end. It deals with session and connection coordination. d. Transport Layer This layer provides transparent transfer of data between en d systems, orhosts, and is responsible for end-to-end error recovery andflow control.It ensures complete data transfer. e. network Layer This layer providesswitchingandroutingtechnologies, creating logical paths, known asvirtual circuits, for transmitting data fromnodeto node. Routing and advancement are functions of this layer, as come up asaddressing,internetworking, error handling, congestioncontrol and packet sequencing. f. Data subsume Layer At this layer, data packets areencodedand decoded into bits. It furnishestransmission protocolknowledge and management and handles errors in the physical layer, flow control and frame synchronization.The data link layer is divided into two sub layers The Media Access Control (MAC) layer and theLogical Link Control(LLC) layer. The MAC sub layer controls how a computer on the network gains access to the data and permission to transmit it. The LLC layer controls frame synchronization, flow control and error checking. g. somatogenic Layer 1 This layer conveys the bit stream electrical impulse, light or radio signal through thenetworkat the electrical and mechanical level. It provides thehardwaremeans of sending and receiving data on a carrier, including defining cables, cards and physical aspects. b) Internetworking tools The art and science of connecting individuallocal-area networks (LANs)to createwide-area networks (WANs), and connecting WANs to form even larger WANs. Internetworking can be extremely abstruse because it generally involves connecting networks that use divers(prenominal)protocols. Internetworking is accomplished ithrouters,bridges, andgateways. Routers It is adevicethat onwards datapacketsalongnetworks. A router is connected to at least two networks, commonly twoLANsorWANsor a LAN and itsISPnetwork. Routers are located atgateways, the places where two or more networks connect.Routers useheadersand forwarding tables to determine the best path for forwarding the packets, and they useprotocolssuc h asICMPto communicate with each other and configure the best route between any two hosts. Bridges It is adevicethat connects twolocal-area networks (LANs), or two segments of the same LAN that use the sameprotocol, such asEthernetorToken-Ring. Gateways It is anodeon anetworkthat serves as an entrance to another network. In enterprises, the gateway is the computer thatroutesthe traffic from a workstationto the outside network that is serving the Web pages.In homes, the gateway is theISPthat connects the user to the internet. In enterprises, the gateway node often acts as aproxy hostand afirewall. The gateway is also associated with both arouter, which useheadersand forwarding tables to determine wherepacketsare sent, and aswitch, which provides the actual path for the packet in and out of the gateway. A computer system located on universe that switches data signals and voice signals between satellites andterrestrialnetworks. An earlier term forrouter, though now obsolete in this s ense asrouteris commonly used. c) Distributed computing systems A distributed computer system consists of multiple software components that are on multiple computers, but run as a single system. The computers that are in a distributed system can be physically nigh together and connected by a local network, or they can be geographically distant and connected by a wide area network. A distributed system can consist of any number of possible configurations, such as mainframes, personal computers, workstations, minicomputers, and so on. The goal of distributed computing is to make such a network work as a single computer.Distributed systems offer many benefits over centralized systems, including the following Scalability The system can easily be expanded by adding more machines as needed. Redundancy Several machines can provide the same services, so if one is unavailable, work does not stop. Additionally, because many smaller machines can be used, this periphrasis does not need to be prohibitively expensive. Distributed computing systems can run on hardware that is provided by many vendors, and can use a variety of standards-based software components. Such systems are independent of the underlying software.They can run on assorted operating systems, and can use various communications protocols. Some hardware might use UNIX(R)as the operating system, while other hardware might use Windows operating systems. For inter machine communications, this hardware can use SNA or TCP/IP on Ethernet or Token Ring. This system contains two local area networks (LANs) that are connected to each other. One LAN consists of UNIX workstations from several different manufacturers the other LAN consists primarily of PCs that are running several different PC operating systems.One of the LANs is also connected to a mainframe by way of an SNA connection. The lymph gland/ horde model A common way of organizing software to run on distributed systems is to separate functions into two par ts customers and waiters. A knobis a program that uses services that other programs provide. The programs that provide the services are calledservers. The client makes a request for a service, and a server performs that service. Server functions often require some resource management, in which a server synchronizes and manages access to the resource, and responds to client requests with either data or location information.Client programs typically handle user interactions and often request data or initiate some data modification on behalf of a user. For example, a client can provide a form onto which a user (a person working at a data entry terminal, for example) can enter orders for a product. The client sends this order information to the server, which checks the product database and performs tasks that are needed for billing and shipping. Typically, multiple clients use a single server. For example, loads or hundreds of clients can interact with a few servers that control dat abase access.The client is isolated from the need to know anything about the actual resource manager. If you change the database that you are using, the server possibly needs to be modified, but the client does not need to be modified. Because usually fewer copies exist of the server than of the client, and because the servers are often in locations that are easier to update (for example, on central machines instead of on PCs that are running on users desks), the update surgical procedure is also simplified. Also, this approach provides additional security. Only the servers, not the clients, need access to the data that the resource manager controls.Clients can also access several different servers, and the servers themselves can act as clients to other servers. Exactly how the functions are distributed across servers is an application design decision. For example, a single server could provide all the services that a client needs, or the client could access multiple servers to per form different requests. The application designer must consider items such as scalability, location, and security. For example, are the clients and servers local or is the application distributed over a wide geographic area? Do the servers need to be on machines that are physically secure?Such design decisions are outside the scope of this introduction. Some servers are part of an application and are referred to asapplication servers. Other servers are not part of a specific application. Instead, any application can use them. For example, the CICS Structured File Server (SFS) provides record-oriented file access for applications. Three-tiered client/server architecture A common design of client/server systems uses three tiers 1. A client that interacts with the user 2. An application server that contains the business logic of the application 3. A resource manager that stores data.