12 DEC 2018

Typologies of computer networks

Computer networks are, fundamentally, sets of interconnected electronic devices, which communicate with each other to exchange information for visualization, storage and processing.

 

Types of computer networks: classifications

The most representative computer network in the world is the internet. The Internet is characterized by a strong heterogeneity of communication protocols and user devices (for example telephones, PCs, sensors, home appliances and so on) and for this reason it should be better thought of as a network of networks.

But what  types of computer networks are found on the internet? Computer networks can be classified in many different ways, based on:

  • type of connection used for communication;
  • physical/logical topology (meaning conformation) of network connections;
  • architecture;
  • geographical extension.

 

Types of connections in computer networks: wireless and cable

The connection within a computer network, meaning the medium by which information is passed, can be of two types: wireless and cable.

Wireless technology allows network connection without the need of cables (which are invasive). The best-known wireless communication protocol is the IEEE 802.11 standard, which is particularly known for being the one most used for internet connection on our PCs and which allows connection distances up to 100 meters (without obstacles).

Other types of wireless connection protocols worthy of note are:

  • Bluetooth: created for the purpose of sharing information quickly, between a few devices which are near (a few meters);
  • mobile network: characterized by the type of data that passes through it, phone calls and SMS messages. The mobile network is becoming more and more common on the Internet, in fact most of the services of telephony and messaging are available on internet applications such as WhatsApp and/or Telegram.

 

Cable connections use cables for data transport and are characterized by a greater speed and reliability in the delivery of information compared to wireless connections. The most commonly used cables in computer networks are:

  • telephone twisted pair: it transmits electrical signals using copper and is characterized by low installation costs and low transmission speeds, it is mainly used in wiring inside houses and/or offices;
  • optical fiber: it works in a totally opposite way: data travels in the form of light signals reflected inside the cable by a mirror system, as shown in the figure:

How the light pulse propagates in the optical fiber

Optical fiber communication is characterized by very high installation costs and is used for data exchange over long distances and in any case within the back-bone of the internet.

Elaborated by Fabrizio Milazzo and Lucia D’Adamo