What is Wireless Fidelity (Wi-Fi)?

Wi-Fi is a wireless technology that enables devices to connect to the internet and communicate with each other over a wireless network without using physical cables. It uses radio waves to transmit data and allows for high-speed, convenient, and flexible communication between devices within its range.

Dissecting Wireless Fidelity (Wi-Fi)

Wireless Fidelity (Wi-Fi) technology was first developed in the late 1990s by a group of engineers at a company called NCR Corporation, which later became part of AT&T. The goal was to create a wireless network technology that could replace Ethernet cables and enable devices to connect to the internet and each other without the need for physical connections.

Wi-Fi Standards

Since its inception, Wi-Fi technology has undergone numerous advancements and innovations. The following are the primary advances and benefits associated with each major Wi-Fi standard.

IEEE 802.11 (1997)

The first Wi-Fi standard, supporting data transfer speeds of up to 2 Mbps using the 2.4 GHz frequency band.

IEEE 802.11b (1999)

Increased data transfer speeds up to 11 Mbps while continuing to operate in the 2.4 GHz frequency band. This standard was more widely adopted due to its improved performance over the original 802.11.

IEEE 802.11a (1999) 

Introduced the use of the 5 GHz frequency band and supported data transfer speeds up to 54 Mbps. Although it was released around the same time as 802.11b, it saw less widespread adoption due to the higher cost of 5 GHz equipment.

IEEE 802.11g (2003) 

Combined the benefits of 802.11b and 802.11a by supporting data transfer speeds up to 54 Mbps while operating in the 2.4 GHz frequency band. This standard offered a significant speed improvement over 802.11b while maintaining backward compatibility with it.

IEEE 802.11n (2009) 

Commonly referred to as Wi-Fi 4, this standard increased data transfer speeds to a maximum of 600 Mbps by utilizing both the 2.4 GHz and 5 GHz frequency bands. It also introduced Multiple-Input Multiple-Output (MIMO) technology, which improved range and reliability by allowing the simultaneous use of multiple antennas.

IEEE 802.11ac (2013)

Also known as Wi-Fi 5, this standard exclusively used the 5 GHz frequency band and offered data transfer speeds of up to 6.9 Gbps. It introduced Multi-User MIMO (MU-MIMO) technology, which allowed access points to communicate with multiple devices simultaneously, improving overall network efficiency.

IEEE 802.11ax (2019)

Also referred to as Wi-Fi 6, this standard operates in both the 2.4 GHz and 5 GHz frequency bands and supports data transfer speeds of up to 9.6 Gbps. It introduced Orthogonal Frequency-Division Multiple Access (OFDMA) technology, which improves network efficiency and latency. Wi-Fi 6 also provides better performance in dense environments, such as crowded public spaces, and improved power efficiency for devices.

Features of Wireless Fidelity (Wi-Fi)

Wi-Fi is a widely-used technology that offers internet connectivity, and it possesses distinctive characteristics that set it apart from other internet technologies. These include:

• Wireless connectivity: Unlike wired technologies such as Ethernet or Digital Subscriber Line (DSL), Wi-Fi provides wireless connectivity, allowing devices to connect to the internet without the need for physical cables. This feature offers increased flexibility, convenience, and mobility for users.
• Use of unlicensed radio spectrum: Wi-Fi operates in unlicensed radio frequency bands, specifically the 2.4 GHz and 5 GHz bands. This allows Wi-Fi devices to be deployed without the need for obtaining licenses or paying fees to regulatory authorities. In contrast, cellular technologies like 4G and 5G require licensed spectrum, which is auctioned off by governments to network operators.
• Infrastructure mode and ad-hoc mode: Wi-Fi supports two main network configurations. Infrastructure mode involves a centralized access point (AP) to which client devices connect, while ad-hoc mode allows direct peer-to-peer connections between devices without the need for an access point. 
• Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) protocol: Wi-Fi uses the CSMA/CA protocol for medium access control. This protocol allows devices to share the wireless medium efficiently while minimizing collisions. In contrast, other technologies such as Ethernet use the Carrier Sense Multiple Access with Collision Detection (CSMA/CD) protocol, which functions differently.
• Wi-Fi Direct: Wi-Fi Direct is a feature that enables devices to establish a direct connection without the need for an access point or an internet connection. This is useful for sharing files, streaming media, or playing multiplayer games between devices. Although other technologies like Bluetooth offer similar functionality, Wi-Fi Direct generally supports faster data transfer rates and longer ranges.
• Wi-Fi Protected Setup (WPS): WPS is a feature that simplifies the process of connecting devices to a Wi-Fi network by using a push button or an 8-digit PIN. This can make it easier for users to add new devices to their network without the need to manually enter complex passwords. Other internet technologies may not offer a similar feature for simplifying the connection process.

How Wireless Fidelity (Wi-Fi) Works

Wi-Fi technology facilitates wireless internet connectivity by employing a series of steps to effectively transmit data between devices. These processes work in tandem to ensure accurate and dependable communication over the airwaves.

1. Data request: The user's device, such as a smartphone or laptop, sends a data request to the connected access point (AP). This request can be for a webpage, a file download, or any other type of data.
2. Access point communication: The access point communicates with the internet, forwarding the user's request to the appropriate server or destination.
3. Server response: The server or destination processes the request and generates a response, which typically consists of data packets containing the requested information.
4. Data transmission: The server sends the data packets back to the access point, which then transmits them wirelessly over the airwaves using the appropriate modulation technique and frequency band.
5. Data reception: The user's device receives the transmitted data packets from the access point through its wireless network interface card (WNIC).
6. Error checking and correction: The user's device checks the received data packets for errors using techniques such as Forward Error Correction (FEC) and Automatic Repeat Request (ARQ). If any errors are detected, the device sends a negative acknowledgement (NACK) to the access point, prompting it to retransmit the affected packets.
7. Acknowledgement: Once the user's device successfully receives and decodes the data packets without errors, it sends an acknowledgment (ACK) to the access point to confirm successful reception.
8. Data processing: The user's device processes the received data, reconstructing the original information (e.g., webpage, file, or media) and presenting it to the user.