Chapter 1 Network Operating Systems ISQA424 Instructor: Rob Knauerhase Portland State University

Chapter 1 Chapter 1: Networking with Microsoft Windows NT Server

Chapter 1 Learning Objectives n Explain workgroup networking n Explain domain networking and the advantages of file server operating systems n Present a history of how Windows NT Server evolved n Describe the capabilities of Microsoft NT Server continued

Chapter 1 Learning Objectives n Compare different file systems used by Microsoft NT Server n Discuss how Microsoft NT Server is integrated with Internet and intranet applications

Chapter 1 Workgroup Networking n Microsoft Windows NT Server is a network operating system -- software that enables computers on a network to communicate and share resources and files n Peer-to-peer network: A network where computers communicate with each other on an equal basis without going through an intermediary

Chapter 1 Workgroup Networking n Workstation u A computer that has its own CPU u May be used as a standalone computer for a variety of software applications n Workgroup: As used in Microsoft networks, a number of computers (users) who share drive and printer resources in an independent peer-to- peer relationship

Chapter 1 A Simple Peer-to-Peer Workgroup Workstation

Chapter 1 Workgroup Networking n Effective for small networks or offices n Less effective when resource management is totally decentralized u Offers only moderate network security u No centralized storage or account management u No point of centralized administrative control u Not optimized for heavy multiple access to one computer; potential for slow response

Chapter 1 Networking in a Domain n Domain: A grouping of network users and file servers to make common administrative and security management tasks more efficient n File server: A computer that provides files and other services to workstations.

Chapter 1 A File Server on a Network Workstation File server with NT Server operating system Workstation Cabling Workstation Laptop computer

Chapter 1 Advantages of the Domain Model n All members can share computer files n Printers and other resources can be shared n Access to resources can be centrally controlled and administered n Members can share software applications (consistency) continued

Chapter 1 Advantages of the Domain Model n All computers can be backed up from one location (easily) n Sharing of resources can reflect work groupings within the domain n Network administrator can save time when installing software upgrades n Detailed monitoring and analysis can be done from a central location

Chapter 1 A History of Microsoft Windows NT n Work began in 1988 when Microsoft had two operating systems u MS-DOS (& early Windows versions) u OS/2 (co-developed with IBM) n Design focused on providing broader capabilities in areas key to business and network users u e.g., needed a “real” operating system u competitive pressure from Mac, Unix

Chapter 1 Original Windows NT Development Goals continued

Chapter 1 Original Windows NT Development Goals

Chapter 1 Microsoft Windows NT Server Capabilities n Sharing resources n Managing resources n Security n Scalability and compatibility n Reliability n Distributability n Client/server applications n Electronic mail n Fault tolerance

Chapter 1 Sharing Resources n Files needed by several people can be stored at one location u Mapped drive: A disk drive that is shared on the network by a file server or workstation. Also known as a drive share. n Data are consistent across machines n Many kinds of printers can be shared on a network n Software can be loaded or run on workstations across network (site license)

Chapter 1 Workstations Accessing a Shared NT Server Hard Drive Workstation Shared drive Windows NT Server Network

Chapter 1 Workstations Sharing One Printer Workstation Hub Shared printer File server

Chapter 1 Managing Resources n Centralizing management of resources allows a network administrator to simplify network management tasks n Network resources u File servers u Workstations u Shared printers u Shared folders

Chapter 1 Security n Windows NT Server has a C2 top secret security rating from the US government u File and folder protection u Account passwords u File, folder, and account auditing u File server access protection on a network u File server management controls n This is a minimum of security; by no means is it perfect.

Chapter 1 Scalability and Compatibility n Scalability u Works on single-processor and multiprocessor computers u Handles small or large databases n Compatibility u Communicates with IBM, Novell, UNIX, Banyan, DEC, and other systems u Works with all (most?) PC hardware, much existing Windows software.

Chapter 1 Reliability n The NT Server operating system kernel runs in privileged mode u Protects operating system from problems created by malfunctioning program u Gives operating system an extra level of security from intruders u Prevents system crashes because of out- of-control applications

Chapter 1 Reliability n NT Server takes full advantage of multitasking and multithreading capabilities of modern Pentium computers u Multitasking: Ability to run two or more programs at the same time u Multithreading: Ability to run several program processes or parts (threads) at the same time

Chapter 1 Distributability n Distributability: The process of dividing complex application program tasks among two or more computers n Windows NT Server handles it through the Distributed Component Object Model (DCOM)

Chapter 1 Client/Server Applications n Began appearing in late 1980s n Provide more information to users than traditional mainframe (unable to meet reporting and data query needs) or file- server-based application systems (unable to handle large databases) n Focus on quickly bringing data to customers

Chapter 1 Technological Tools of Client/Server Applications n Relational databases n Graphical user interfaces (GUIs) n Powerful reporting tools n More powerful PC workstations n Networks

Chapter 1 Relational Databases n Store large amounts of data on a server n Provide fast access to data for updating, querying, or reporting n Store data, voice, and video n Provide open access paths to a variety or reporting and development tools

Chapter 1 Three Tiers of Client/Server Systems n PC client workstation u Contains GUI presentation logic n Application server u Stores client/server applications and reports used by client n Database server u Provides data-related services, including security

Chapter 1 Client/Server Application System Database server (data services) Client workstation (GUI presentation services Application server (business process services)

Chapter 1 Electronic Mail n Critical network application F even grandmothers have these days... n Fast and convenient F companies see strong benefits from interaction among employeesamong employees between employees and customersbetween employees and customers n Enables use of distribution lists F much like

Chapter 1 Fault Tolerance Options n Recovery from hard disk failures n Recovery from lost data in a file n Recovery from system configuration errors n Protection from power outages n Advanced warning about system and hardware problems n Recovery from network connectivity failures

Chapter 1 Server File Systems n File allocation table (FAT) file system n NT file system (NTFS) n NT also allows conversion of the High Performance File System (HPFS) to NTFS F eases transition from OS/2

Chapter 1 FAT File System n Based on the use of a file allocation table, a flat table that records the blocks used to store the data contained in each file on a disk F blocks - units of disk storage n Used by several operating systems (MS-DOS, Windows 95, Windows NT) n Does not support advanced security and auditing

Chapter 1 Advantages of FAT n Simple system, supported by many small computer operating systems n Low operating system overhead n Supports partitions up to 4 GB

Chapter 1 Disadvantages of FAT n Can become corrupted over time as files are spread among disjointed allocation units, and pointers to each unit are lost n Does not offer many file or directory security or auditing options n Does not support long filenames (11 character limit, “8 dot 3” convention)

Chapter 1 NTFS n Native Windows NT file system n Has a detailed directory structure n Supports C2 security specifications n Supports large disks, long filenames, and file compression n Keeps a log of file system activity n Supports Portable Operating System Interface (POSIX)

Chapter 1 HPFS n Used by the OS/2 operating system n Not supported by Windows NT 4.0

Chapter 1 Choosing a File System continued

Chapter 1 Choosing a File System

Chapter 1 Internet Integration and Electronic Commerce n Internet u Global network of diverse WWW and information servers offering voice, video, and text data to millions of users u Major source of commerce n Intranet u Private network within an organization u Restricted from public access

Chapter 1 Internet Information Server (IIS) for NT Server n Gives organizations ability to take advantage of intranet and Internet software n Index Server: Built-in service which automatically indexes information created for intranet access within a company

Chapter 1 Chapter Summary n Windows NT Server is an operating system meant for networking. u Provides more options for network productivity and growth u Offers many resource options for shared folders, printers, and other resources u Provides network management facilities through domains and groups u Has built-in protection from crashes continued

Chapter 1 Chapter Summary n NT Server enables scalability and distributability. u Gives options to scale up to larger and more powerful hardware u DCOM compatibility offers solid foundation for distributed application services such as client/server applications continued

Chapter 1 Chapter Summary n NT Server supports FAT and NTFS. u Installation depends on file sizes, volume size, security needs, and purpose of server and number of users n NT Server offers access to and integration of Internet and intranet services through Microsoft’s Web server software, IIS, and built-in Index Server service.