What is an Access Point?

An access point refers to a networking hardware device that allows devices, such as computers, smartphones, and tablets, to connect wirelessly to a wired network. Access points are commonly used to extend the coverage of a network and to enable users to connect to the internet within the area covered by the wireless signal. They work by receiving data from a wired network and converting it into a wireless signal, which is then transmitted to devices within range. 

Dissecting Access Point

The history of wireless access points can be traced back to the early 1990s, when the need for a wireless networking solution emerged due to the increasing number of computers and the desire for greater mobility. A pivotal moment in the development of access points came with the creation of the IEEE 802.11 standard in 1997. This standard established a framework for wireless local area networks (WLANs) and marked the beginning of the widespread adoption of wireless access points.

Development of Access Point

The development of access points has gone through several stages, driven by the evolving needs of users and advancements in technology.

1. Early access points (1990s): In the early stages of wireless networking, access points primarily functioned as simple bridges between wired and wireless networks. These devices were proprietary and lacked standardization, which led to compatibility issues between different manufacturers. As the demand for wireless connectivity grew, the need for a standardized approach became more evident.
2. Adoption of IEEE 802.11 standard (1997): With the introduction of the IEEE 802.11 standard, access points started to become more standardized and interoperable. This allowed for greater compatibility between devices from different manufacturers and made it easier for users to set up and manage wireless networks.
3. Improvements in hardware and software: Over the years, access points have seen significant advancements in hardware components, such as processors, memory, and antennas. These improvements have enabled access points to handle more simultaneous connections, offer better coverage, and provide higher data rates. Additionally, the development of more sophisticated firmware and management software has made access points easier to deploy, configure, and maintain.
4. Integration of security features: As the use of wireless networks became more widespread, the need for better security features in access points became apparent. The introduction of security protocols, such as WEP, WPA, and WPA2, allowed access points to provide encrypted communication and protect the integrity of the wireless network.
5. Centralized management and cloud-based solutions: In the mid-2000s, the concept of centralized management emerged, allowing network administrators to manage multiple access points from a single location. This led to the development of Wireless LAN Controllers (WLCs) and later, cloud-based management platforms. These solutions simplified the deployment and management of large-scale wireless networks, making it easier for businesses and organizations to adopt wireless technology.
6. Mesh networking and seamless roaming: As wireless networks continued to grow in size and complexity, the need for better coverage and seamless roaming between access points became more important. Mesh networking, which involves the interconnection of multiple access points to form a single, unified network, provided a solution to these challenges. Access points supporting mesh networking can automatically route traffic between nodes, ensuring optimal performance and seamless connectivity for users as they move throughout the network.
7. Integration with IoT and smart devices: With the rise of the Internet of Things (IoT) and the increasing prevalence of smart devices, access points have evolved to support these new technologies. Modern access points often include features such as Bluetooth and Zigbee connectivity, which enable them to communicate with various IoT devices and sensors.

How Access Point Works

In order to sustain an active connection between access points and client devices, continuous communication is needed. These coordinated processes contribute to the consistent quality and reliability of the wireless link.

1. Data packet reception: When an access point receives data packets from a wired network, it first processes and prepares them for transmission over the wireless network. This involves encapsulating the data packets with the appropriate headers and trailers based on the Wi-Fi standard in use (e.g., 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, or 802.11ax).
2. Modulation: Modulation is the process of converting digital data into a format suitable for transmission over radio waves. Access points use various modulation schemes, such as Quadrature Amplitude Modulation (QAM), Quadrature Phase-Shift Keying (QPSK), and Binary Phase-Shift Keying (BPSK), depending on the Wi-Fi standard and the conditions of the wireless channel. The chosen modulation scheme determines the number of bits that can be transmitted per symbol, affecting the data rate of the wireless network.
3. Channel access: Before transmitting data, the access point must determine when it can access the wireless channel to avoid collisions with other devices. Wi-Fi networks use a contention-based protocol called Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA). With CSMA/CA, the access point listens to the wireless channel to check if it is idle. If the channel is busy, the access point waits for a random period before trying again. If the channel is idle, the access point proceeds with data transmission.
4. Encoding and transmission: Once the access point has modulated the data and gained access to the channel, it encodes the modulated data using a technique called Orthogonal Frequency Division Multiplexing (OFDM) or, in some cases, High Throughput Orthogonal Frequency Division Multiplexing (HT-OFDM) for more recent Wi-Fi standards. OFDM divides the modulated data into multiple subcarriers, which are then transmitted simultaneously over the wireless channel using radio waves.
5. Reception by client devices: The radio waves carrying the encoded data are received by the antennas of client devices, such as smartphones, laptops, or tablets. The client devices demodulate and decode the received signal, extracting the original data packets. These data packets are then processed and passed up the networking stack to the appropriate application or service.



Features of an Access Point

Access points come with a variety of features that enhance their performance, usability, and security. Some key features of an access point are:

• Multiple frequency bands: Modern access points often support both 2.4 GHz and 5 GHz frequency bands, providing greater flexibility and reducing interference from other devices operating in the same spectrum.
• Multiple Input Multiple Output (MIMO) technology: MIMO allows access points to use multiple antennas for transmitting and receiving data, improving signal strength, coverage, and data rates.
• Beamforming: This feature focuses the Wi-Fi signal towards specific client devices, improving signal strength and reducing interference, which can lead to better overall performance.
• Quality of Service (QoS) support: Access points with QoS features can prioritize different types of network traffic, ensuring that bandwidth-sensitive applications like video streaming and voice calls receive sufficient resources for optimal performance.
• PoE (Power over Ethernet) support: Access points with PoE support can receive power through an Ethernet cable, eliminating the need for a separate power supply and simplifying installation.
• Guest network capabilities: Some access points allow the creation of separate guest networks, providing internet access to visitors without exposing the main network's resources.