Small Wireless Network Basics | CompTIA Tech+ FC0-U71 | 2.9

In this post, we’re going to take an in-depth look at small wireless networks.  We’ll cover the most common wireless networking standards:  802.11n, 802.11ac, and 802.11ax, and explore factors like speed, interference, attenuation, and band options.  We’ll also compare older and newer standards and explain how different frequency bands, such as 2.4GHz, 5GHz, and 6GHz, impact network performance.

Overview of Wireless Networking Standards

First, let’s talk about wireless networking standards.

The IEEE 802.11 standards are the set of protocols that define wireless networking.  Each standard specifies how wireless devices communicate over a network and sets parameters like speed, frequency, and range.  Over the years, these standards have evolved to meet increasing demands for faster speeds and better performance.

The most commonly used standards today are:

• 802.11n (also known as WiFi 4)
• 802.11ac (also known as WiFi 5)
• 802.11ax (also known as WiFi 6)

Let’s explore each of these standards in more detail.

802.11n (WiFi 4)

The 802.11n standard, or WiFi 4, was released in 2009 and is still widely used in many home and small business networks.  It improved on earlier standards by offering:

• Dual-Band Support:  It operates on both the 2.4GHz and 5GHz frequency bands, allowing users to select a frequency based on their needs.
• Speeds Up to 600 Mbps:  802.11n introduced the ability to reach theoretical speeds of up to 600 megabits per second (Mbps), significantly faster than its predecessors.
• MIMO (Multiple Input Multiple Output):  This technology uses multiple antennas for both transmitting and receiving, improving speed and range.

However, while 802.11n provides a decent level of performance, it’s been surpassed by more recent standards that deliver faster speeds and better handling of network congestion.

802.11ac (WiFi 5)

Next is 802.11ac, or WiFi 5.  Introduced in 2014, this standard further improved wireless speeds and performance:

• Faster Speeds:  802.11ac can achieve speeds up to 3.5 gigabits per second (Gbps) under optimal conditions, making it over 5 times faster than 802.11n.
• 5GHz Frequency Band Focus:  It primarily operates in the 5GHz band, which is less crowded than the 2.4GHz band, reducing interference and enabling faster data transfer.
• MU-MIMO (Multi-User MIMO):  While 802.11n introduced MIMO, 802.11ac improved upon it with MU-MIMO, allowing multiple devices to receive data simultaneously.  This is great for environments with many connected devices, like households or small offices.

802.11ac provided significant speed and performance improvements over 802.11n, but as more devices began connecting to wireless networks, a new standard was needed to handle the increased demand.

802.11ax (WiFi 6)

The latest standard, 802.11ax, also known as WiFi 6, was released in 2019.  It focuses on improving not just speed but also efficiency and capacity:

• Higher Speeds:  WiFi 6 supports speeds up to 9.6 Gbps, a massive leap from 802.11ac.
• Efficient Multi-Device Management:  With OFDMA (Orthogonal Frequency Division Multiple Access), WiFi 6 can divide a wireless channel into smaller frequency allocations, allowing multiple devices to be served simultaneously without congestion.
• TWT (Target Wake Time):  This feature optimizes device power usage, allowing connected devices to “wake up” and transmit data only when needed, which is particularly useful for IoT devices.
• Operates on 2.4GHz, 5GHz, and 6GHz Bands:  Unlike 802.11ac, WiFi 6 operates on both the 2.4GHz and 5GHz bands, offering backward compatibility and flexibility for different network environments.  WiFi 6E also expands to the 6GHz band, offering even more bandwidth and reduced interference.

WiFi 6 is designed to meet the increasing demands of modem devices, providing better performance in crowded networks and delivering faster, more reliable connections.

Speed Considerations & Comparison

When comparing these standards, speed is a crucial factor.

• 802.11n supports speeds up to 600 Mbps, which is sufficient for most basic internet activities like web browsing, video streaming, and email.
• 802.11ac can reach speeds up to 3.5 Gbps, making it ideal for high-definition video streaming, online gaming, and multiple device connections.
• 802.11ax (WiFi 6) reaches up to 9.6 Gbps and can handle high-density environments with many connected devices, ensuring stable and high-speed connections.

Keep in mind, these are theoretical maximum speeds.  Actual speeds may vary due to factors like interference, distance, and network congestion.

Interference & Attenuation Factors

Now, let’s talk about interference and attenuation.

• Interference occurs when other devices operate on the same frequency band, causing the wireless signal to degrade.  For example, microwaves, baby monitors, and Bluetooth devices all operate on the 2.4GHz band and can interfere with WiFi signals.
• Attenuation refers to the weakening of a signal as it travels through the air or through objects like walls and furniture.  Higher frequency bands, like 5GHz and 6GHz, have a shorter range and are susceptible to attenuation than the 2.4GHz.

This is why it’s important to choose the right frequency band based on the environment.  The 2.4GHz band has a longer range but is more prone to interference, while the 5GHz band offers faster speeds with less interference but over a shorter distance.  The 6GHz band in WiFi 6E provides even faster speeds and lower latency but also has a limited range.

Band Options:  2.4GHz, 5GHz, and 6GHz

Let’s break down the three main frequency bands used in wireless networks:

• 2.4GHz Band
  • Longer Range, Lower Speeds:  It has a greater reach and can penetrate walls better, but its maximum speed is slower than higher frequency bands.
  • Crowded Band:  Many household devices use this band, leading to potential interference.
• 5GHz Band
  • Higher Speeds, Shorter Range:  This band provides faster data transfer rates than 2.4GHz but with a reduced range.
  • Less Interference:  Since fewer devices use this band, there is generally less interference.
• 6GHz Band (WiFi 6E)
  • New & Efficient:  The newest addition to WiFi frequency options, offering even faster speeds and lower latency.
  • Less Congestion:  Since fewer devices currently operate on this band, it provides a cleaner, more efficient experience.

Choosing the right band depends on your network needs.  For long-range connections or environments with many obstacles, the 2.4GHz band may be preferable.  For faster speeds with reduced interference in a smaller area, 5GHz or 6GHz bands are better options.

Older vs. Newer Standards

Let’s discuss older versus newer standards.

Older standards like 802.11a, 802.11b, and 802.11g were the predecessors of the standards we discussed earlier.  They offered much slower speeds, with 802.11b capping at 11 Mbps and 802.11g at 54 Mbps.  They were also limited to either the 2.4GHz or 5GHz band, without dual-band capabilities.

As technology evolved, newer standards like 802.11n, 802.11ac, and 802.11ax provided faster speeds, better handling of multiple devices, and more efficient use of the frequency spectrum.  When setting up a small wireless network, opting for modern standards like WiFi 5 or WiFi 6 ensures optimal performance and future-proofs the network as technology continues to advance.

Conclusion

To recap, we’ve covered the key standards of wireless networking – 802.11n, 802.11ac, and 802.11ax – and explored their speed capabilities, interference and attenuation factors, and frequency band options:  2.4GHz , 5GHz, and 6GHz.  Understanding these fundamentals will help you design and manage a small wireless network effectively, and it’s essential knowledge for the CompTIA Tech+ FC0-U71 exam.