The following points summarize the key concepts of this chapter.
Introduction to Network Operating Systems
- Without a network operating system (NOS) of some kind, individual computers cannot share resources, and other users cannot make use of those resources.
- An NOS can be part of a computer operating system or a separate application that runs on top of the computer operating system.
- Windows NT is an example of an operating system that incorporates both computer and network operating systems in one system.
- By multitasking, computers can perform more than one task at a time.
- Multitasking can be either preemptive or nonpreemptive.
- Server software is the means by which an NOS provides services to other computers on a network.
- A redirector is used to forward client requests to the network.
- Using redirectors, users can access peripheral devices as if the devices were attached directly to the client computer.
- The first step in choosing a network operating system is to decide which network architecture—client/server or peer-to-peer—best meets your needs; this can often be accomplished by determining what level of security your network requires.
Novell Operating Systems
- NetWare client software is designed to be installed over a client computer's operating system.
- The NetWare NOS is designed to work in multivendor network environments.
- NetWare Directory Services (NDS) provide a database that maintains information about every resource on the network.
- NDS provides security, routing, messaging, management, Web publishing, file and print services, and name services.
- A NetWare network requires both NetWare Server software for the server and NetWare Client software for each workstation.
Microsoft Network Operating Systems
- Windows NT is Microsoft's network operating system.
- Windows NT incorporates both the computer and the network operating system into one.
- Windows NT Server is the server module of the network.
- Windows NT Workstation is the client module of the network.
- Windows NT networks are designed to take advantage of the domain model in which all computers share a common security database. This information is stored on a server that is designated as the domain controller. Windows Server and Workstation will operate as part of a peer-to-peer network (share model), but you will not be able to take advantage of the additional security features provided in the domain model.
- Windows NT provides several utilities to provide interoperability between NetWare and Windows NT.
Other Network Operating Systems
- Apple IP allows non-Apple users to access Apple resources such as database files.
- A UNIX computer can be used as a file server by installing file-server software.
- Banyan Vines is a network operating system based on the Xerox proprietary protocol.
- Banyan Vines is a server/client-based network operating system.
- Peer-to-peer LAN networking is popular for small offices in which maintaining network security is not an issue.
- Windows for Workgroups, Windows 95 and 98, and OS/2 Warp NOSs have built-in peer-to-peer LAN software.
Network Operating Systems in a Multivendor Environment
- Interoperability in multivendor environments can be achieved from either the client or server computer.
- Redirectors are used to intercept requests for services and forward them across the network to the appropriate network services.
- A client or a server can have multiple redirectors.
- The three primary manufacturers of products for multivendor environments are Novell, Microsoft, and Apple.
- Apple computers connect to personal computer networks by means of network servers.