LI-FI (Light Fidelity) is a modern technology that promises to be 100 times faster than the existing WI-FI technology.
LI-FI uses the Visible Light Communication (VLC) which was first developed by Harold Haas of the University of Edinburgh in 2011 to transmit data at incredible speeds.
Basically, this acts like an extremely fast signal light, flickering on and off to relay messages in binary code (1s and 0s).
During the last years, research and developments have been carried out to take advantage of the use of light as a means to improve Internet connectivity.
This concept is known as Li-Fi, which means by its translation of English, light fidelity.
Unlike conventional wireless connectivity, Li-Fi makes use of lamps and other light sources to achieve faster speeds. Is this technology enough to completely displace the use of Wi-Fi?
Although the LiFi technology is still in the experimental stage, it should be noted that it promises to be the wireless network of the near future and that it will replace the well-known Wi-Fi wireless system over time.
Let’s see why and what are the advantages and disadvantages of Li-Fi technology.
Comparison Between LI-FI & WI-FI
1. Speed
LI-FI can offer speeds of up to 500 Mbps (megabits per second).
WI-FI 6th generation can achieve speeds of up to 9.6 Gbits per second over fiber. The 5e category UTP cables can support 1Gbits per second, and in case of glass fiber, dozens of Gigabits per second are esasily achievable.
Even taking into account the real device capabilities, and limitations of radio environment, it is still way more than 500Mb/s.
From this explanation WI-FI remains way faster than LI-FI. Interference problems are hardly present in today’s rf communications.
2. Affordability
Li-Fi transmits data using light with the help of LED bulbs. A lamp driver, LED bulb (lamp) and photo detector will make up complete Li-Fi system.
Wi-Fi transmits data using radio waves with the help of Wi-Fi router. Wi-fi requires routers to be installed, subscriber devices(laptops, PDAs, desktops) are referred as stations.
A special light bulb is required for a LI-FI system to work not just any light bulb or lamp. Inorder to modulate the signal ,the light source needs to be capable to blink (in reality its more complex) millions of times per second.
Current light bulbs, even the modern LED ones, have too much inertia to achieve any reasonable speed. So its rather expensive to have to replace everything apart from mains power cables.
In LI-FI, light bulbs are sources , and additional detectors will be needed.
3. Security
In Li-Fi, light is blocked by the walls and hence will provide more secure data transfer.
In Wi-Fi, RF signal cannot be blocked by the walls and hence need to employ techniques to achieve secure data transfer.
The security of any data transmission system should be based on strong encryption and reliable user authentication, whereas this feature of light can be only a small nice-to-have.
While in most institutions like banks, nothing surpasses cables for security.
Conclusion
There can be many disadvantages to LI-FI, as well. Its biggest drawback comes in the form of infrastructure (or lack, thereof).
Since LiFi technology is a relatively new concept and is currently in its introductory stage, the infrastructure necessary to implement the technology in a large enough scale is still virtually non-existent.
This means that plenty of time is still required before the general public can enjoy LI-FI technology.
Another disadvantage is that the light source will need to be constantly turned on in order to provide network access. This problem can be solved by dimming the light enough to levels that the human eye can perceive as turned off, but are actually still on.
In cases where dimming the light is out of the question, however, this could be a problem.
Another perceived disadvantage of LI-FI connections is that because it relies on light to transmit data, it becomes highly susceptible to outside interference.
Photodiodes are able to pick up light from competing sources of light such as sunlight and other forms of illumination. This could potentially create noise within the receiver and cause disruptions to the network.
In most LiFi systems, an optical filter has been installed on photodiode devices in order to filter noise so that the receiver can only pick up signals coming from the transmitter.
Lastly, users are rendered immobile when using LI-FI systems due to the limited range of the signal given off by light bulbs.
This is, of course, countered by installing multiple LI-FI systems within large spaces, creating as many connections as there are light bulbs.