Network security has indeed become a priority for all of us. A significant amount of vital information is shared and stored within wireless networks nowadays that it has become necessary to protect the network itself from those that seek to profit off of all these pieces of information.

In the wireless revolution, WiFi has taken over as the go-to channel for data transmission for most, if not all, networks around the world. However, its widespread use has also lead to the discovery of various security flaws within the WiFi system itself. These security issues, coupled with WiFi’s struggle to cope with the ever-growing demand for wireless connectivity, has led us to search for newer technologies that can not only meet our needs for greater connectivity but are also more secure than previous technologies. This led to the emergence of LiFi technology.

LiFi, which uses visible light for the transmission of data, is considered to be more secure than its predecessor. In fact, security is built into the channel itself. In order to understand how LiFi is more secure than WiFi, or any other wireless networking system for that matter, it is important to understand the properties of light in contrast with the properties of radio waves.

Properties of Radio Waves

Radio waves are a type of electromagnetic radiation, similar to microwaves, ultraviolet radiation, infrared, x-rays, and gamma rays, but have much lower frequencies (3 kHz to 3 THz) with corresponding wavelengths ranging from as low as 100 micrometers to 100 kilometers. Among those found in the electromagnetic spectrum, radio waves have the lowest frequencies and the longest wavelengths.

The propagation of radio waves tells us how they move in free space and over the surface of the Earth. This determines how far radio waves can travel at certain frequencies. Practical radio systems use three different techniques for the propagation of radio waves. These methods are line of sight, ground waves, and sky waves.

For wireless communication, the method of propagation used is indirect propagation, which is at a point just beyond line of sight. This allows radio waves transmitted at low enough frequencies to pass through various obstructions such as walls, buildings, and other obstructions. But beyond that, it also allows waves to circumvent obstructions through diffraction and reflection. These methods occur in short-range communication systems such as mobile phones, cordless phones, walkie-talkies, and WiFi networks. Its biggest drawback, however, is its tendency for multipath propagation. For wireless networks, this makes these networks susceptible to interferences and various reception problems.

Properties of Radio Waves

Radio waves are a type of electromagnetic radiation, similar to microwaves, ultraviolet radiation, infrared, x-rays, and gamma rays, but have much lower frequencies (3 kHz to 3 THz) with corresponding wavelengths ranging from as low as 100 micrometers to 100 kilometers. Among those found in the electromagnetic spectrum, radio waves have the lowest frequencies and the longest wavelengths.

The propagation of radio waves tells us how they move in free space and over the surface of the Earth. This determines how far radio waves can travel at certain frequencies. Practical radio systems use three different techniques for the propagation of radio waves. These methods are line of sight, ground waves, and sky waves.

For wireless communication, the method of propagation used is indirect propagation, which is at a point just beyond line of sight. This allows radio waves transmitted at low enough frequencies to pass through various obstructions such as walls, buildings, and other obstructions. But beyond that, it also allows waves to circumvent obstructions through diffraction and reflection. These methods occur in short-range communication systems such as mobile phones, cordless phones, walkie-talkies, and WiFi networks. Its biggest drawback, however, is its tendency for multipath propagation. For wireless networks, this makes these networks susceptible to interferences and various reception problems.

Properties of Visible Light

The visible light spectrum comprises a portion of the electromagnetic spectrum that corresponds to frequencies of 430 – 770 THz and wavelengths of 390 to 700 nanometers. It contains all colors of light that humans are capable of seeing unaided. There are a variety of properties that set apart visible light from other types of electromagnetic radiation.

White light contains all the colors contained within the entire spectrum. When white light passes through a prism, the light scatters, revealing all the colors visible to the human eye in the form of a rainbow – from near ultraviolet with a wavelength of 380 nanometers to near infrared with a wavelength of 700 nanometers.

Visible light exists as both a particle and a wave. This property is called a wave-particle duality, which creates a variety of interesting traits. Because of the wave aspect of light, just like any other wave, means light can travel in every direction, interact with other waves, and bend. These waves travel in ultra-high speeds – at 186,000 miles per second – in a vacuum but slow down considerably when passing through denser materials such as water and air. This explains why visible light waves, unlike radio waves, are unable to pass through opaque walls.
Light can also exist as particles called photons. These photons are released when another particle of the same energy passes by one photon. This continuous stream of photons being released by a light source is what is what we perceive as light.

Security Features of WiFi and LiFi

Aside from the differences in the properties of radio waves and visible light, there are a variety of differences in the security features of both WiFi and LiFi.

WiFi Security Features

The Institute of Electrical and Electronics Engineers (IEEE) is an international organization that maintains standards on wireless connectivity through 802.11, the IEEE workgroup in charge of Wireless LAN. A variety of protocols for 802.11 have been enacted by the committee over time. Below is a list of these protocols along with their maximum speed and frequencies.

• 802.11a
  • Frequency: 5.0 GHz
  • Typical Maximum Speed: 54 Mbps
• 802.11ac
  • Frequency: 5.0 GHz
  • Typical Maximum Speed: 6 Gbps
• 802.11b
  • Frequency: 2.4 GHz
  • Typical Maximum Speed: 11 Mbps
• 802.11g
  • Frequency: 2.4 GHz
  • Typical Maximum Speed: 54 Mbps
• 802.11n
  • Frequency: 2.4 or 5.0 GHz
  • Typical Maximum Speed: 600 Mbps

Before pieces of data are transmitted using radio frequency, they are encoded using 802.11 standards and are then encoded and decoded using 802.11 standards-compliant routers. The data that is passed through WiFi routers are processed within the 2.4 GHz to 5.0 GHz range. This leads to some issues to security. In order to compensate for these security issues, various security solutions were introduced to increase its security. These include:

Wired Equivalent Privacy (WEP)

WEP was the first security measure introduced to provide more confidentiality to wireless networks. It was part of the IEEE 802.11 standard ratified in September 1999, which used the RC4 stream cipher for confidentiality and the CRC-32 checksum for integrity. It was later identified to be poorly-implemented by vendors and was susceptible to attacks.

WiFi Protected Access (WPA and WPA2)

WPA replaced WEP in 2003 as an improved security standard for wireless networks. It was the first generation of advanced wireless security for both home and enterprise users. It introduced new layers of security as networks were encrypted using the RC4 cipher and added the use of network keys to prevent unwanted access. It was further improved in 2004 with the introduction of WPA2 to limit packet forgery. Both WPA and WPA2 came with two versions, namely: WPA-Personal and WPA-Enterprise wherein users can be authenticated using a set-up password and an authentication server, respectively.

WiFi Security Concerns

Even with the security features installed on WiFi connections, there are still numerous concerns over their security. That is because WiFi networks are still vulnerable to different forms of attacks. One of these attacks includes password cracking, which makes use of brute force attacks to gain the password of the network. Another is war driving, which entails driving around neighborhoods in order to take note of different wireless networks around the area as well as the network type and other pertinent information.

There are also cases wherein network administrators do not feel obligated to secure the data shared over their networks. This opens up more security concerns as users will have no control over the interception and modification of their data.

LiFi Security Features

LiFi technology is widely considered to be generally more secure than WiFi. Plenty of security features can be embedded in LiFi systems in order to make them more secure. While these features may come in the near future when LiFi is in wide circulation, it is already considered more secure due to several security characteristics.

Localized Coverage

For LiFi connections, communication only takes place in areas that light can touch. In wide open spaces, each light can be directed towards certain areas within specific spaces in order to create different network zones – each light corresponds to a specific network. This makes it possible for certain networks to restrict access to people from certain departments.

Reduced Leakage

Because visible light is localized and easily-contained within opaque walls, more secure connections can be created as easily as closing the blinds and windows – basically restricting light. Because visible light cannot pass through walls, communication is extremely localized to areas that are confined by opaque walls. This means those that wish to connect to the network need to be physically within the room to access the network, making sure that external access to the network is impossible while also making it easier to physically track those connecting to the network. This also makes it easier to create secure ad-hoc networks for users to share data with each other without the risk for data leaks.

Conclusion

The nature of radio waves used in WiFi has made WiFi connections unstable and vulnerable to external threats. That is several security features were placed on WiFi systems based on security standards in order to make wireless networks more secure. These features are still vulnerable to attacks, especially if the technology catches up and more people figure out how to exploit these features. On the other hand, LiFi is considered to be more secure mainly because even in the absence of encryption and other security features, the nature of the connection makes it easier to secure connections, restrict access, and track users. The addition of more security protocols to LiFi systems will not only enable high-speed connectivity but also create the opportunity for creative security solutions to make connections more secure.