In order for a network to communicate successfully, all the separate functions of the individual components discussed in the preceding sections must be coordinated. On the other hand, networks based on client-server NOSs are comprised of client workstations that access network resources made available through the server. The advantages and disadvantages of each are discussed in the following sections. For example, each networked computer can allow other computers to access its files and use connected printers while it is in use as a workstation. They are also easy to install and are usually inexpensive.
Maintenance is also often more difficult.
In a client-server network the NOS runs on a computer called the network server. The server must be a specific type of computer. A client-server NOS is responsible for coordinating the use of all resources and services available from the server on which it is running. The client part of a client-server network is any other network device or process that makes requests to use server resources and services. For example, network users at workstations request the use of services and resources though client software, which runs in the workstation and communicates with the NOS in the server by means of a common protocol.