Operating System Quick Guide. Operating System Quick Guide. Operating System Overview. An Operating System OS is an interface between a computer user and computer hardware. Table Of Contents. Digital CertificatesPKI for IPSec VPNs. Contents. Design Guide Structure. Overview. Architectural Design Considerations. Configuring the Cisco IOS. An operating system is a software which performs all the basic tasks like file management, memory management, process management, handling input and output, and controlling peripheral devices such as disk drives and printers. Some popular Operating Systems include Linux Operating System, Windows Operating System, VMS, OS4. AIX, zOS, etc. Definition. An operating system is a program that acts as an interface between the user and the computer hardware and controls the execution of all kinds of programs. Following are some of important functions of an operating System. Memory Management. Processor Management. Types+of+Processing+Job+Shop+Batch+Repetitive%2F+Assembly+Continuous.jpg' alt='Advantages And Disadvantages Of Serial Processing Operating System' title='Advantages And Disadvantages Of Serial Processing Operating System' />Device Management. File Management. Security. Control over system performance. Job accounting. Error detecting aids. Coordination between other software and users. Memory Management. Memory management refers to management of Primary Memory or Main Memory. The disadvantages of RFID are easily outweighed by the advantages and in many cases can be minimized to the point where theyre insignificant. Operating System Quick Guide Learning operating system concepts in simple and easy steps A beginners tutorial containing complete knowledge about an operating. DBMS A database management system is the software system that allows users to define, create and maintain a database and provides controlled access to the data. Main memory is a large array of words or bytes where each word or byte has its own address. Main memory provides a fast storage that can be accessed directly by the CPU. For a program to be executed, it must in the main memory. An Operating System does the following activities for memory management Keeps tracks of primary memory, i. In multiprogramming, the OS decides which process will get memory when and how much. Allocates the memory when a process requests it to do so. De allocates the memory when a process no longer needs it or has been terminated. Processor Management. In multiprogramming environment, the OS decides which process gets the processor when and for how much time. This function is called process scheduling. An Operating System does the following activities for processor management Keeps tracks of processor and status of process. Advantages And Disadvantages Of Serial Processing Operating System' title='Advantages And Disadvantages Of Serial Processing Operating System' />The program responsible for this task is known as traffic controller. Allocates the processor CPU to a process. De allocates processor when a process is no longer required. Device Management. An Operating System manages device communication via their respective drivers. It does the following activities for device management Keeps tracks of all devices. Program responsible for this task is known as the IO controller. Decides which process gets the device when and for how much time. Allocates the device in the efficient way. De allocates devices. File Management. A file system is normally organized into directories for easy navigation and usage. These directories may contain files and other directions. An Operating System does the following activities for file management Keeps track of information, location, uses, status etc. The collective facilities are often known as file system. Decides who gets the resources. Allocates the resources. De allocates the resources. Other Important Activities. Following are some of the important activities that an Operating System performs Security By means of password and similar other techniques, it prevents unauthorized access to programs and data. Control over system performance Recording delays between request for a service and response from the system. Job accounting Keeping track of time and resources used by various jobs and users. Error detecting aids Production of dumps, traces, error messages, and other debugging and error detecting aids. Coordination between other softwares and users Coordination and assignment of compilers, interpreters, assemblers and other software to the various users of the computer systems. Types of Operating System. Operating systems are there from the very first computer generation and they keep evolving with time. In this chapter, we will discuss some of the important types of operating systems which are most commonly used. Batch operating system. The users of a batch operating system do not interact with the computer directly. Each user prepares his job on an off line device like punch cards and submits it to the computer operator. To speed up processing, jobs with similar needs are batched together and run as a group. The programmers leave their programs with the operator and the operator then sorts the programs with similar requirements into batches. The problems with Batch Systems are as follows Lack of interaction between the user and the job. CPU is often idle, because the speed of the mechanical IO devices is slower than the CPU. Difficult to provide the desired priority. Time sharing operating systems. Time sharing is a technique which enables many people, located at various terminals, to use a particular computer system at the same time. Time sharing or multitasking is a logical extension of multiprogramming. Processors time which is shared among multiple users simultaneously is termed as time sharing. The main difference between Multiprogrammed Batch Systems and Time Sharing Systems is that in case of Multiprogrammed batch systems, the objective is to maximize processor use, whereas in Time Sharing Systems, the objective is to minimize response time. Multiple jobs are executed by the CPU by switching between them, but the switches occur so frequently. Thus, the user can receive an immediate response. For example, in a transaction processing, the processor executes each user program in a short burst or quantum of computation. That is, if n users are present, then each user can get a time quantum. When the user submits the command, the response time is in few seconds at most. The operating system uses CPU scheduling and multiprogramming to provide each user with a small portion of a time. Computer systems that were designed primarily as batch systems have been modified to time sharing systems. Advantages of Timesharing operating systems are as follows Provides the advantage of quick response. Avoids duplication of software. Reduces CPU idle time. Disadvantages of Time sharing operating systems are as follows Problem of reliability. Question of security and integrity of user programs and data. Problem of data communication. Distributed operating System. Distributed systems use multiple central processors to serve multiple real time applications and multiple users. Data processing jobs are distributed among the processors accordingly. The processors communicate with one another through various communication lines such as high speed buses or telephone lines. These are referred as loosely coupled systems or distributed systems. Processors in a distributed system may vary in size and function. Advertising Agency Website Templates. These processors are referred as sites, nodes, computers, and so on. Read about serial and parallel battery configurations. Connecting battery cells gains higher voltages or achieves improved current loading. These systems had minimal operating systems and were typically mainframe computers used to support commercial and scientific applications. Jobs and programs were. Deployment Models chapter of the Cisco Collaboration System 11. SRND. The advantages of distributed systems are as follows With resource sharing facility, a user at one site may be able to use the resources available at another. Speedup the exchange of data with one another via electronic mail. If one site fails in a distributed system, the remaining sites can potentially continue operating. Better service to the customers. Reduction of the load on the host computer. Reduction of delays in data processing. Network operating System. A Network Operating System runs on a server and provides the server the capability to manage data, users, groups, security, applications, and other networking functions. The primary purpose of the network operating system is to allow shared file and printer access among multiple computers in a network, typically a local area network LAN, a private network or to other networks. Examples of network operating systems include Microsoft Windows Server 2.