What is Wi-Fi?

What is Wi-Fi?

Wi-Fi is a wireless networking technology that uses radio frequency signals to connect various devices to enable communication and exchange of information. The term Wi-Fi is not an acronym, it is usually believed that Wi-Fi is a short form for Wireless fidelity, but the organization Wi-Fi alliance which owns the Wi-Fi trademark clarifies that Wi-Fi is just a more user-friendly name for IEEE 802.11b Direct Sequence Spread Spectrum (DSSS), but now the term Wi-Fi is used for other standards as well. Wi-Fi uses two different types of radio frequencies which are 2.4 gigahertz and 5 gigahertz.

Wi-Fi is used for line-of-sight communication because of high absorption levels and constraints such as walls, pillars, etc greatly reduce the range of the Wi-Fi. We can use various other devices such as repeaters, boosters, and range extenders to increase the range of Wi-Fi.

How Does Wi-Fi Work?

The working principle behind Wi-Fi is the use of radio waves to transmit data between your device and a Wi-Fi router. The two different frequencies mainly used for communication are 2.4 gigahertz and 5 gigahertz. These are further divided into multiple channels to enable the device to send and receive data. A 2.4 GHz band has 11 channels and a 5 GHz band has 45 channels.

The data transfer is controlled as follows when a user wants to interact with the internet. The request is converted to radio signals, which are transmitted using the Wi-Fi adapter. These transmitted requests are then received by the routers which convert the radio signal back to machine language which is then sent to the destination using a wired connection. When the response to the request is received, a similar pathway is followed to send back the information through the router to the user’s device.

Some More Terminologies

Some terms which are also used with Wi-Fi are:

1. SSID – SSID is a short form for Service Set Identifier or more commonly known as your Wi-Fi network name. The maximum length of SSID is 32 characters. More or less the main purpose of SSID is just for identification of your own Wi-Fi network. You may also choose to hide your SSID by turning off your SSID broadcast.

2. WPA – PSK – The term WPA – PSK is made up of two terms that is WPA which is short for Wi-Fi Protected Access and PSK which is short for Pre-Shared Key. This is a data encryption technique used for a wireless LAN using the pre-shared key mode. The three types of WA modes available are WPA, WPA2, and WPA3. This pre-shared key allows the printer and computers to directly join your wireless network.

3. Ad Hoc – This is a type of network in which the devices connect and communicate with each other rather than relying on the base station or access points. The network is ad hoc since it doesn't depend on established infrastructure, such as routers in wired networks or access points in wireless networks. Each device takes part in the routing process by utilizing the routing algorithm to determine the path and send data to other devices along that route.

Types of Wi-Fi

Based on the generation and the IEEE standards of Wi-Fi these are classified into different types:

Types of Wi-Fi Connections

There can be two types of Wi-Fi connections that are from routers or mobile hotspots. Router – It is a hardware device that is used to connect multiple devices and allows them to use the same internet connection. It can also be used as an access point that creates a wireless network also known as a Wi-Fi network. This device takes ethernet as input and provides a middleman that helps the client connect and communicate through that ethernet wirelessly.

Mobile Hotspot – Mobile phones have a feature called a mobile hotspot which is used to create a Wi-Fi network by creating a hotspot that uses the cellular network capabilities of the mobile phone to provide internet for other devices connected in the network.

Elements of Wi-Fi

The various elements of Wi-Fi include: Access point – An access point is a networking device that allows other Wi-Fi devices to connect to a wired network. This device needs a router to be connected through a wire connection. A router may be used as an access point but not vice versa.

Wireless adapter – A wireless adapter is a networking device that is connected to a computer to provide the computer Wi-Fi functionality in computers where in-built network cards are not available. A wireless adapter is of two types that are connected to the USB port of the computer or the one which is directly connected to the PCI slot of the motherboard.

Router – A router is a networking device that is used to direct traffic on the internet. It is used to forward data packets to their intended locations. It uses various routing algorithms and routing tables to route the data to the destination. Some routers also work as access points that provide wireless connections to connect our Wi-Fi devices.

Bridge - A bridge is a networking device that is used to connect a larger LAN network with a group of smaller LAN networks. Bridges are different from routers as bridging joins two separate networks as if they were a single network but routing permits several networks to communicate with one another while remaining independent. The main standard is a wireless distribution system.

Repeater – A Repeater is a networking device that is used to retransmit the signal to expand the coverage area of the access point. These devices receive the signal, regenerate or amplify the signal and then retransmit it thus expanding the coverage of the signals. They are also called signal boosters.

Embedded systems – Embedded systems with a limited Graphical user interface can be easily connected to the internet using WPS (Wi-Fi Protected Setup). WPS provides the option for push button configuration or PIN configuration.

Wi-Fi Cards – These are modern forms of Wi-Fi adapters. These compact chips are similar to Wi-Fi adapters and they are nowadays preinstalled in laptops and smartphones to provide Wi-Fi functionality.

Safeguards – Some of the safeguards include the usage of firewalls to protect the network from attackers is the use of firewalls. These firewalls prevent any unauthorized actions and attackers from performing any malicious activity.

Wi-Fi Use Cases

There are many use cases of Wi-Fi which include:

• It allows us to connect to various devices wirelessly. For example, multiple computers can be connected to share resources and if a printer is connected to the network, then it can be accessed from any computer wirelessly.
• It can be used to provide internet connectivity to all the devices connected to the computer network.
• It can be used to provide voice over Wi-Fi which provides the facility of transferring voice call data over Wi-Fi rather than conventional cellular networks.
• It can be used to connect Internet of Things (IoT) devices. These devices when combined with Wi-Fi can be used very efficiently.
• It is used in public venues such as airports, cafes, malls, etc. to engage with guests and improve their overall experience.
• It provides high-speed internet wirelessly removing the need to connect wires to devices and improving the user experience.
• It empowers big projects like the smart city projects resulting in internet connectivity to all through government-provided Wi-Fi.

Wi-Fi Security Options

To prevent unauthorized access to our Wi-Fi network we need to implement some security measures. It ensures that the data is accessible only to authorized users. There are four types of security protocols available which include Wired Equivalent Privacy (WEP), Wi-Fi Protected Access (WPA), Wi-Fi Protected Access 2 (WPA 2), and Wi-Fi Protected Access 3 (WPA 3). WPA 3 is the most secure choice available. WEP and WPA are both outdated and should not be used further.

• Wired Equivalent Privacy (WEP) was the first security protocol that was developed in 1997 and used a combination of user and system-generated key values to encrypt. But it has been reverse-engineered and the encryption method is cracked which makes any device using the WEP encryption vulnerable.
• Wi-Fi Protected Access (WPA) was developed to overcome the flaws of WEP and it used Temporal Key Integrity Protocol (TKIP) or Pre-Shared KEY (PSA) for encryption. But it too had some flaws which were exploited by hackers to gain authorized access. Wi-Fi Protected Setup (WPS) can be used to bypass security measures.
• Wi-Fi Protected Access 2 (WPA 2) was developed as an advanced version of WPA and it used Advanced Encryption Standard (AES) to encrypt the data. WPS must be switched off to prevent any option for attack.
• Wi-Fi Protected Access 3 (WPA 3) is the most recent type of security protocol available. It uses the CCMP - 128 and AES - 128 encryption methods. It uses a four-way handshake with Simultaneous Authentication of Equals (SAE).

Advantages

• Wi-Fi provides a wireless connection to devices connected to the network leading to increased efficiency and providing more flexibility to users.
• Wi-Fi removes the need for installation and maintenance of wires thus reducing the overall cost.
• It can be easily expanded based on the requirement.
• It offers high data connection rates resulting in faster data transfer.
• It can be used to connect a large variety of devices including mobile phones, laptops, embedded systems, etc.

Disadvantages

• Initial installation of Wi-Fi systems may be a bit hard and also network may not be distributed evenly in the entire office or house.
• Also, there could be a possible source of interference resulting in poor user experience.
• There might be places where the signal does not reach or the transmission speed is very less resulting in a bad user experience.
• Sometimes there is a requirement for the installation of repeaters or multiple access points resulting in some increased costs.
• Wireless systems are prone to cyber-attacks in terms of packet sniffing, De-authentication attacks, etc.
• Routers and access points require a constant electricity supply for functioning which might result in possible work loss in case the electricity goes off.

Difference between WLAN and Wi-Fi

Wireless Local Area Networks (WLAN) and Wi-Fi are commonly confused to be the same term but they are different. This can be understood by the following statement, Wi-Fi is a certain type of WLAN that uses the 802.11 standards of the wireless protocol family. A WLAN might not always use Wi-Fi but uses radio technologies to connect devices in the network.