Networks for rookies part 2

There are several devices that can be part of a net, for instance workstations, servers and network appliances. These devices can be grouped into four basic types: 1. Hosts, 2. Shared peripherals, 3. Networking devices, 4. Networking media.
Most of the people are very familiar with hosts and shared peripherals. We call hosts the devices that send and receive messages from the network. Therefore all the computers that are connected to the network are called hosts.
The shared peripherals are connected to hosts and not directly to the network. The installed operating system is responsible for sharing the peripheral across the net. All the hosts have an operating system like Windows to enable users on the network to use the attached peripherals.
In order to interconnect hosts we use other network devices and special network media. Modern operating systems allow computers to act as a client, a server, or both. Also the installed applications determine if the computer will act as a client or server.
Servers provide information and services to other computers and users inside the network. For example a server can provide email services, web services and so on. Every single service requires a special server application.
On the other hand, clients have software installed that allows them to request and display the information they received from the server. For example, every time you open your web browser application you are asking a web page from a web server.
The good thing about the modern server is that they can provide services simultaneously to several users. Furthermore, a single server can run many types of server applications. Sometimes small businesses have only one server that runs all the server applications.
Modern computers can also run several types of client software at the same time. Usually different software is installed for every service required. Moreover, clients are able to connect to many servers at the same time. For instance, a user can check his emails, view a web page and listen to an online radio station simultaneously. Keep in mind also that a computer can function as a server and as a client on the network. The network that every computer has both roles is called a peer to peer network.
The basic disadvantage of a peer-to-peer network is that the performance of a computer can be seriously affected if it is working as both a client and a server at the same time.
Large corporations use dedicated server for every single service. Dedicated servers are faster and much more reliable than computers in a peer-to-peer network.