Wi-Fi standards (802.11 a/b/g/n/ac/ax) in Computer Networks - Step-by-Step Execution

Concept Flow - Wi-Fi standards (802.11 a/b/g/n/ac/ax)

Start: Wi-Fi Standards

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802.11a: 1999, 5 GHz, 54 Mbps

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802.11b: 1999, 2.4 GHz, 11 Mbps

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802.11g: 2003, 2.4 GHz, 54 Mbps

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802.11n: 2009, 2.4/5 GHz, up to 600 Mbps

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802.11ac: 2013, 5 GHz, up to 3.5 Gbps

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802.11ax (Wi-Fi 6): 2019, 2.4/5 GHz, up to 9.6 Gbps

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End: Faster, better Wi-Fi

Wi-Fi standards evolved over time, each improving speed, frequency, and features step-by-step.

Execution Sample

Computer Networks

Standard | Year | Frequency | Max Speed
802.11a | 1999 | 5 GHz     | 54 Mbps
802.11b | 1999 | 2.4 GHz   | 11 Mbps
802.11g | 2003 | 2.4 GHz   | 54 Mbps
802.11n | 2009 | 2.4/5 GHz | 600 Mbps
802.11ac| 2013 | 5 GHz     | 3.5 Gbps
802.11ax| 2019 | 2.4/5 GHz | 9.6 Gbps

This table shows the main Wi-Fi standards with their release year, frequency band, and maximum speed.

Analysis Table

Step	Standard	Year	Frequency Band	Max Speed	Key Feature
1	802.11a	1999	5 GHz	54 Mbps	First 5 GHz Wi-Fi, faster than b
2	802.11b	1999	2.4 GHz	11 Mbps	Popular, longer range but slower
3	802.11g	2003	2.4 GHz	54 Mbps	Faster 2.4 GHz, backward compatible with b
4	802.11n	2009	2.4/5 GHz	600 Mbps	Dual band, MIMO for speed and range
5	802.11ac	2013	5 GHz	3.5 Gbps	Wide channels, MU-MIMO for multiple devices
6	802.11ax (Wi-Fi 6)	2019	2.4/5 GHz	9.6 Gbps	Improved efficiency, better in crowded areas
7	End	-	-	-	Latest standard with highest speed and efficiency

💡 Reached latest Wi-Fi standard 802.11ax with highest speed and efficiency improvements.

State Tracker

Standard	Frequency Band	Max Speed
802.11a	5 GHz	54 Mbps
802.11b	2.4 GHz	11 Mbps
802.11g	2.4 GHz	54 Mbps
802.11n	2.4/5 GHz	600 Mbps
802.11ac	5 GHz	3.5 Gbps
802.11ax	2.4/5 GHz	9.6 Gbps

Key Insights - 3 Insights

Why does 802.11b have a slower speed than 802.11a even though they were released the same year?

802.11b uses the 2.4 GHz band which has more interference and lower max speed (11 Mbps), while 802.11a uses 5 GHz with less interference and higher speed (54 Mbps), as shown in execution_table rows 1 and 2.

Why is 802.11n faster than 802.11g even though both support 2.4 GHz?

802.11n supports both 2.4 and 5 GHz bands and uses MIMO technology to send multiple data streams, increasing speed up to 600 Mbps, unlike 802.11g which maxes at 54 Mbps (see execution_table rows 3 and 4).

What makes 802.11ax (Wi-Fi 6) better for crowded places?

802.11ax improves efficiency with technologies like OFDMA and better MU-MIMO, allowing many devices to connect smoothly, as noted in execution_table row 6.

Visual Quiz - 3 Questions

Look at the execution_table at step 4. What is the maximum speed of 802.11n?

A 3.5 Gbps

B 600 Mbps

C 54 Mbps

D 11 Mbps

💡 Hint

Check the 'Max Speed' column at step 4 in the execution_table.

At which step does the Wi-Fi standard first support both 2.4 GHz and 5 GHz bands?

A Step 3 (802.11g)

B Step 5 (802.11ac)

C Step 4 (802.11n)

D Step 6 (802.11ax)

💡 Hint

Look at the 'Frequency Band' column in the execution_table for dual band support.

If 802.11ac supported 2.4 GHz as well, how would the frequency band column change at step 5?

A It would show '2.4/5 GHz'

B It would remain '5 GHz'

C It would show '2.4 GHz' only

D It would be blank

💡 Hint

Check how dual band is represented in the frequency band column for 802.11n and 802.11ax.

Concept Snapshot

Wi-Fi standards evolved from 802.11a/b/g to n, ac, and ax.
Each new standard improved speed and frequency bands.
2.4 GHz offers longer range but slower speeds; 5 GHz is faster but shorter range.
MIMO and OFDMA technologies boost speed and efficiency.
802.11ax (Wi-Fi 6) is the latest, best for crowded networks.

Full Transcript

Wi-Fi standards started with 802.11a and 802.11b in 1999, differing mainly by frequency and speed. 802.11a used 5 GHz for faster speeds (54 Mbps), while 802.11b used 2.4 GHz with slower speed (11 Mbps). Later, 802.11g improved 2.4 GHz speeds to 54 Mbps. The 802.11n standard introduced dual-band support (2.4 and 5 GHz) and MIMO technology, increasing speeds up to 600 Mbps. Then 802.11ac focused on 5 GHz with wider channels and MU-MIMO, reaching up to 3.5 Gbps. The latest, 802.11ax or Wi-Fi 6, supports both bands with better efficiency and speeds up to 9.6 Gbps, ideal for crowded environments. This progression shows how Wi-Fi technology improved over time to provide faster and more reliable wireless connections.