Computer networks: types, architecture, and communication models

¶ … breakthroughs since the introduction of computers in our society is the development of network technology. Nowadays, almost all business and companies worldwide are implementing the state-of-the-art capabilities of computer networks.

What is a Network? A Network is a collection of computers connected to each other enabling communication between each terminal. Through wires, cables, and devices such as network hubs and switches, computer terminals can form a group of connection which we call network.

Network has 2 types of connection that is based on the location of the connected computers: the LAN, and the WAN. The LAN or Local Area Network is a connection of computers that are located in one same particular area, such as within a room or within a building. WAN or Wide Area Network, on the other hand, is a connection of computers capable of communicating in any location such as computers located in different cities or countries. One best example of WAN is the Internet.

A network provides easy access of information, reducing the need of traveling to a particular place just to do the traditional sending and retrieval of necessary information. A LAN for instance, allows employees of a company to access information from other departments, or communicate with other employees, through computer applications that communicate over a network.

Client and Server

When computers communicate over a network, regardless of the type of its connection whether a LAN or a WAN, the two important factors of networking is the Client and the Server.

In simple definition, the Client is the interface that makes a request while the Server is the interface that grants the Client's request.

To provide a clear definition of the Client and Server terms, let us use a practical example of a WAN service - the Internet. Everyday, the Internet is being accessed for diverse data needs by a large number of users worldwide. The Internet, being the provider of this data service, can be called the Server. The users who access the Internet and request for data are the Clients.

Beyond the Internet as being the Server, there are thousands of other servers within the Internet. The locations from which the Internet users request for web pages are also called servers.

The Working Network

Networks have driving aspects that makes it work. These aspects are the network's technology, topology, and protocol. Ethernet and Token Ring are two of the many types of a network technology. TCP/IP and IPX, on the other hand, are among the popular protocols (How do Networks Work?) data packet is a network element sent to computers within a network. This packet serves as the storage data space of each computer, which it also sends to the other terminals after storing data in the packet. How data packets are sent to each computer depends on the type of a network's topology. For instance, a Ring Topology sends data packets to each computer in a circular manner (i.e one computer after another).

When a data packet containing information is sent to a computer, it compares its destination address against the computer's address. A match of address will enable the data packet to transmit the information to the computer. Otherwise, the data packet will continue searching for its destination until it is found. The process of sending, receiving, storing data, and sending back of data packets continue in a network until terminals are no longer connected.

Network applications and software make network communication possible. Such includes e-mails, Internet browsers, chat applications, etc. They are the mediums of communication between computer terminals connected in a network. Without these applications, a connected terminal will remain useless in terms of network communication.

Basically, the electronic wires, cables, network hardwares, software, and users, make a network communication possible. Without these elements, there will be no data sending and receiving.