Networking Operating Systems (CO32010)

Transcription

1 Networking Operating Systems (CO32010) 2. Processes and scheduling 1. Operating Systems 1.1 NOS definition and units 1.2 Computer 7. Encryption Systems 1.3 Multitasking and Threading 1.4 Exercises 6. Routers 5. Routing protocols 8. NT, UNIX and NetWare 3. Distributed processing Objectives: To outline the main areas covered in the module. To define some of the basic terminology of operating systems. To define the main components of a network operating system. To define the differences in operating systems. 4. Distributed file systems

2 Definition of an NOS The infrastructure that allows the reliable distribution of processes, files systems, networking components, networking protocols, and other associated components in order to produce a system which is reliable and secure, and which operates within a required specification. Encryption Routing Protocols Distributed Processing Processing and scheduling Distributed File Systems Router Programming and Security

3 Server 3. Distributed Processing 7. NOS s Router 2. Processes and scheduling Router 5. Routing Protocols Router 6. Router Programming Router 8. Encryption 5. Distributed file systems

4 Areas covered Introduction. This unit provides a basic introduction to some of the concepts involved with operating systems, such as the basic definition involved in computer systems. Processes and Scheduling. This unit outlines some of the key concepts in the operation of an operating system, especially related to processes, and scheduling. Distributed Processing. This units outline some of the standard methods which are used to control the distribution of processes over a network. A key focus is on the RPC protocol, which is a standard method for distributing processes. Distributed File Systems. This unit outlines some of the methods which can be used to distribute file systems over a network. A key focus of this unit is the NFS standard, which can be used to distribute file system over a network. Routing Protocols. This unit outlines some of the key methods, and problems that occur with standard routing protocols Routers and ACLs. This unit outlines how routers are programming, and how ACLs can be applied to facilitate network security. Encryption. This unit outlines the principles of methods which allow data to be encrypted. Networking Operating Systems. This unit outlines the three main networking operating systems: UNIX, Novell NetWare and Microsoft Windows.

5 Hardware, Operating Systems and User Interfaces User User interface: interface: Microsoft Microsoft Windows Windows (Windows (Windows 95/NT/2000/XP). 95/NT/2000/XP). Microsoft Microsoft Windows Windows X-Windows. X-Windows. Operating Operating system: system: Microsoft Microsoft Windows Windows (Windows (Windows 95/NT/2000?XP). 95/NT/2000?XP). DOS. DOS. UNIX/Linux. UNIX/Linux. VMS. VMS. Novell Novell NetWare. NetWare. Hardware: Hardware: x86 x86 architecture. architecture. SPARC SPARC architecture. architecture. Apple Apple architecture. architecture.

6 Hardware, Operating Systems and User Interfaces User account database Operating System Groups Users Operating system Kernel Kernel Volumes File system Resources Memory Print Queues Printer Printer Server

7 Operating system characteristics Single-user Multi-user Stand-alone Networked Single-tasking Multitasking Single processor Multi-processor

8 Operating system characteristics Local processing Distributed processing Embedded Non-embedded

9 Operating Systems Memory: - Creating virtual memory systems - Disk swapping for memory Hardware Mac OS Unix Linux DOS Microsoft Windows 95/98 (OS) Microsoft Windows NT (OS) Device interfacing: - Access to connected devices - Multi-user access - Device drivers Multiprocessing - Allowing several processes to run, at a time - Scheduling of processing to allow priority Networking: - Remote login/file transfer - Creating global file systems File system: - Creating a file system - Copying/deleting/moving files Multi-user - Allowing users to login into system - Allows users permissions to certain resources - Manage queues for resources

10 Application program Application program Operating System Components Communication with operating system Operating System Mouse driver Network driver Kernel Video driver Soundcard driver Keyboard driver

11 Information passed between processes Process Process Data passed between processes Process Process Interrupt Message or signal Interrupt Low-level Low-level interrupt interrupt Low-level Low-level interrupt interrupt Network or local computer

12 Preemptive Multitasking Come Come on. on. My My turn turn soon soon 1 Processor Okay Okay No.1, No.1, you ve you ve had had your your turn, turn, get get to to the the back back of of the the queue. queue. Next! Next! Process queue Pre-emptive multitasking: Processes are given some time on the processor. This allows all the processes to have some time on the processor, and makes for smoother and more reliable operation

13 Hurray. Hurray. I I could could stay stay here here forever. forever. Anyway, Anyway, I m I m not not going going back back to to the the end end of of the the queue. queue. 1 Co-operative Multitasking Hurry Hurry up. up. I m I m waiting. waiting. You ve You ve been been on on that that processor processor for for ages. ages. This This isn t isn t very very fair! fair! Processor Sorry. Sorry. You ll You ll have have to to wait wait until until he s he s finished finished Process queue Co-operative multitasking: Processes must yield from the processor, before other processes can run on the processor

14 Splitting a process into threads Process approach Threads approach Process Interlinking of threads Process splits into threads Threads Independent threads Common sharing of data between threads