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A technology capable of transmitting data through light has been around for more than a decade, but it is still not very popular. This way of connecting to the network increases up to 100 times the speed of an average wi-fi. Data is transmitted via a light signal that is imperceptible to the human eye. Li-fi is cheaper, faster, and safer than wi-fi, so it could soon replace it, or could it?

The replacement of wi-fi?

Li-fi or light fidelity is a technology that uses LEDs to transmit data that is received by photoreceptors. This technology belongs to the VLC or Visible light communication family. It is an alteration of the visible light frequency that varies between 400 and 800 THz.

To achieve the transmission of the information, the bulb is connected to an encoder, which turns on and off and sends the data. It can be connected to an Ethernet network, receiving data as an electrical signal, which is then retransmitted as a light signal via the LED. This technology has also been tested with infrared rays, reaching a speed of 42.8 Gb, but studies in laboratories have reached up to 224 Gb.

Advantages and disadvantages

Li-fi has too many advantages, the main ones being:

  • Speed
  • Security
  • Less interference

Unlike wi-fi, its light counterpart can use the entire visible light spectrum. Wi-Fi, on the other hand, is limited to a bandwidth of between 2.4 and 5 GHz, which means that all connections are crammed into a single space.

Security can be seen from two aspects. On the one hand there is a protection of human health, as li-fi does not transmit electromagnetic waves. This is below the WHO recommendations. The absence of these waves allows this technology to be compatible with airplanes and hospitals.

The other approach to security is the fact that in order to be able to connect to the li-fi network the user must be under the light emitted by the LED. Outside this range the connection is not possible. Because, unlike electromagnetic waves, light does not pass-through walls and objects, which makes it easier to isolate a network in a more secure way. This makes an attack more difficult, as the hacker would have to be under the light of the bulb.

On the other hand, one of the main disadvantages of li-fi is that it has to be illuminated, without light there is no connection. It only takes a little obstruction of the receiver for the transmission speed to be affected. In addition, the fact that it cannot pass through objects is also a disadvantage, since in order to provide a connection to a whole building, it is necessary to place the necessary bulbs to illuminate the entire space, as each bulb has a very limited range.

The future of li-fi

An entire city could be connected to the internet in public places, just by placing Li-Fi bulbs in buses, trains, streetcars, public lighting, etc. In addition, this technology is inexpensive and can be easily embedded in smartphones, tablets and computers. The French company Oledcomm succeeded in integrating Li-Fi technology into phones and connected objects via a chip.

However, this is a very ambitious future, as currently, the infrastructure does not exist to achieve the aforementioned. In order to provide an entire city with Li-Fi, governments would have to replace all the light bulbs in public places and public transport, which is not an easy nor economical task. On the other hand, at present, manufacturers of technological products do not contemplate the implementation of this type of connection in their devices. Therefore, a future with pure li-fi is far from happening.