Wireless Standards - N10-008 CompTIA Network+ : 2.4
Summary
TLDRThis script discusses the evolution of IEEE 802.11 wireless standards from 802.11a/b in 1999 to 802.11ax in 2021. It covers their frequencies, speeds, and technologies like MIMO and OFDMA. 802.11a/b operate at 5 GHz and 2.4 GHz with speeds up to 54 Mbps and 11 Mbps respectively. 802.11g upgraded to 54 Mbps at 2.4 GHz, compatible with b. 802.11n introduced MIMO, working at up to 600 Mbps on 2.4/5 GHz. 802.11ac boosted speeds to 7 Gbps at 5 GHz with multi-user MIMO. 802.11ax, or Wi-Fi 6, supports up to 9.6 Gbps with bi-directional MIMO in 2.4/5 GHz bands, designed for high-density areas.
Takeaways
- 📡 The IEEE 802.11 standards define wireless LAN/MAN communications, with the Wi-Fi Alliance ensuring device interoperability.
- 🚀 In 1999, the initial 802.11 standards were 802.11a (5 GHz, 54 Mbps) and 802.11b (2.4 GHz, 11 Mbps).
- 📶 802.11a operates at 5 GHz with a higher data rate but shorter range compared to 802.11b at 2.4 GHz.
- 📉 The range of 2.4 GHz devices is roughly one-third that of 5 GHz devices, due to frequency absorption and reflection characteristics.
- 📱 The 2.4 GHz band is more congested with devices like baby monitors, cordless phones, microwaves, and Bluetooth.
- 🆕 In 2003, 802.11g was introduced as an upgrade to 802.11b, matching 802.11a's speed at 54 Mbps but at 2.4 GHz.
- 🔋 802.11n, released in 2009, is an improvement over previous standards, offering dual-band operation and higher throughputs up to 600 Mbps.
- 📈 802.11n introduced MIMO technology, enhancing data transmission capabilities with multiple antennas.
- 🌐 802.11ac, or Wi-Fi 5, further improved upon 802.11n by operating primarily in the 5 GHz band with up to 160 MHz channel bandwidth and multi-user MIMO.
- 🏎️ 802.11ax, or Wi-Fi 6, succeeded 802.11ac, offering high-density support with OFDMA for efficient communication in crowded areas.
- 📚 The progression from 802.11b to 802.11ax shows significant increases in speed and efficiency, with 802.11ax achieving up to 9.6 Gbps theoretical throughput.
Q & A
What is the IEEE 802.11 Standards Committee responsible for?
-The IEEE 802.11 Standards Committee is responsible for maintaining all the standards for wireless communication on local area networks and creating new versions of these standards.
What does the Wi-Fi trademark specifically refer to?
-The Wi-Fi trademark specifically refers to the IEEE 802.11 standards.
What is the role of the Wi-Fi Alliance?
-The Wi-Fi Alliance is a group that handles interoperability testing for all devices that need to connect to an 802.11 network.
When were the initial 802.11 standards released?
-The initial 802.11 standards were released in October of 1999.
What are the operating frequencies and speeds of the 802.11a standard?
-The 802.11a standard operates in the 5 GHz range and has a speed of 54 megabits per second.
What is the general rule of thumb regarding the range of 2.4 GHz compared to 5 GHz technologies?
-As a general rule of thumb, technologies operating at 2.4 GHz can be expected to have about one-third the range of those operating at 5 GHz.
Why is the 802.11a standard not commonly seen on today's networks?
-The 802.11a standard is not commonly seen on today's networks because it operates at 5 GHz, where fewer devices operate, and it has been superseded by newer standards.
What is the difference between 802.11b and 802.11g standards?
-The 802.11b standard operates at 2.4 GHz with a speed of 11 megabits per second, while 802.11g is an upgrade to 802.11b, operating at the same frequency but at a higher speed of 54 megabits per second.
What new features does the 802.11n standard introduce?
-The 802.11n standard introduces the ability to operate on both 2.4 GHz and 5 GHz frequencies, larger channel widths, and a new technology called MIMO (multiple input, multiple output).
What is the maximum theoretical throughput of the 802.11n standard?
-The maximum theoretical throughput of the 802.11n standard can reach around 600 megabits per second when using a 40 MHz mode and four separate antennas.
How does the 802.11ac standard improve upon the 802.11n?
-The 802.11ac standard improves upon 802.11n by operating exclusively in the 5 GHz range, allowing for larger bandwidths up to 160 MHz, channel bonding, denser signal modulation, and multi-user MIMO with up to eight downlink streams.
What are the key features of the 802.11ax standard?
-The 802.11ax standard, also known as Wi-Fi 6, operates at both 5 GHz and 2.4 GHz ranges, supports bi-directional multi-user MIMO over eight streams, and introduces OFDMA for high-density communication environments.
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