Question: How do you build communication networks?

Anna Zakrzewska answered on 3 Mar 2020:

Let us first think how we communicate. There is a person preparing a meesage and then sends it (can be voice, a letter or maybe smoke signal) over the air. This is then received by the recipient who tries to understand the message. It may be too noisy to hear, the letter may be delayed or the smoke will disappear too fast and some signals are lost. We can observe the same in communication networks. In general, there is a sender, receiver, and the medium, which can be air as in the example above or when you use wireless networks or copper/fiber when everything is wired.

A communication network connects the senders and receivers, which can be human or device, and makes it possible to send messages. When we design and build networks, first we need to understand how many people/devices will need to be connected, and also the type of messages that will be sent. Is it a short message saying: ‘I’m a sensor number XXX and this is the latest temperature measurement’ or are the messages very long, like video recordings. Then, we need to select the transmission technology, wireless or wired? If wireless, then Wi-Fi or LTE/5G? Finally, when these decisions are made, someone needs to plan where to put the network devices, such as big core network routers or customer equipment. They need to have access to power (sometimes we can use solar or wind energy) and often cannot be too far from the final senders/receivers. For mobile technologies, you may see base stations and antennas on top of buildings in the cities and towns, and on steel towers in the countryside. All this requires very careful planning and there are special teams that do it. Once the plan is ready, we can finally install the equipment in the places that were selected. We conect the network devices with each other, and we test if everything works as it should. And only now we can invite the users to connect and send their messages. As you see, it’s a very long process that involves many people: from designers of the network equipment, through network planners, engineers and testers, to customer support teams. Today, the whole world is connected with a huge web, there are even cables under the oceans, so that we can reach nearly anyone on Earth!