BARNALI CHAKRABARTY. What is an Operating System ?

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BARNALI CHAKRABARTY Slide 2 What is an Operating System ? Slide 3 Features of Operating System Multi user Multiprocessing Multitasking Multithreading Real time Slide 4 Classification of Services [Chow07] Primitive Services fundamental functions that the kernel must provide Services by System Servers- services that need not reside in the kernel but are still essential Value Added Servers services that are not essential in implementation but are useful in supporting distributed applications Slide 5 Primitive Services Communication- Exchange of Information between processes Synchronization- Coordination of Events Slide 6 Services by System Servers Name Server - used to locate users, processes or machines Network Server used to translate addresses and locations obtained from Name server Time Server-synchronization of processes to maintain a total order of event occurrences File Server- managing shared file system resources Slide 7 Value Added Services Web Server accepts requests from the clients, processes it and returns a response Group Server manages creation and termination of groups of interacting processes Slide 8 Classification of Services [Galvin05] Services that are helpful to users Services for efficient operation of system Slide 9 Operating System Services that are helpful to users User Interface Program Execution I/O Operations File System Operations Error Detection Slide 10 User Interface The means by which the user interacts with the system Consists of Input Output Slide 11 Program Execution Loading Running Execution Slide 12 I/O Operations The communications between the computer and the outside world Slide 13 File System Manipulation Programs need to read and write files and directories, create and delete them, search them, list file Information Slide 14 Error Detection OS needs to constantly monitor possible errors and should take an appropriate action to rectify the error Slide 15 Services for efficient operation of system Resource Allocation Accounting Protection and Security Slide 16 Resource Allocation Resource allocation must be properly done when multiple users or multiple jobs running concurrently. Slide 17 Accounting OS keeps track of what kind of resources used, how many users etc Slide 18 Protection and Security Ensuring that all access to system resources is controlled Access to the system from outsiders requires user authentication Slide 19 WebOS: A Framework of OS services for wide area Applications[A.Vahdat97] Global Naming Wide-Area File System Security and Authentication Process Control Slide 20 Privacy as an Operating System Service [S.Iosannidis06] Approach 1.Transparent, privacy-providing storage and network 2. Privacy-enhanced system calls 3. Privacy Libraries 4. Privacy-policy Management Slide 21 System Support for Many Task Computing [E.V.Hensbergen,08] The paper deals with issues of scale by leveraging the large number of nodes to spread operating systems services and components across the machine, tightly coupling the operating system. The authors plan on provisioning nodes to provide workload execution, aggregation, and system services, and dynamically re-provisioning nodes as necessary to accommodate changes, failure, and redundancy. Slide 22 Future Work Implementation and Development of Liquid Operating system, which is spontaneous and adaptive to dynamically meet the changing requirements of the user. Slide 23 References [1]http://www.webopedia.com/TERM/o/operating_system.html [2]Wikipedia [3]Distributed Operating Systems and Algorithm Analysis, Andy Chow & Theodore Johnson,1997 [4] Operating System Concepts, Silberschatz, Galvin and Gagne,2005 [5] WebOS: Operating System Services for Wide Area Applications,Amin Vahdat et al,1997 [6] Privacy as an operating system service,Ioannidis,S; Sidiroglou,S; D. Keromytis,A;Proceedings of the 1st USENIX Workshop on Hot Topics in Security,2006 [7] System support for many task computing, Van Hensberger, E.; Minnich, R.;Many-Task Computing on Grids and Supercomputers, 2008. MTAGS 2008. Workshop on 17-17 Nov. 2008 Page(s):1 - 8