Wireless Networking Standards

Wi-Fi Standards (IEEE 802.11)

The IEEE 802.11 family defines wireless LAN behavior. CompTIA expects you to recognize each standard's band, ceiling speed, and marketing name on sight.

Exam tell: if a question says a device "works on 2.4 GHz only," it is b, g, or n on that radio. If it says "5 GHz only," the answer is almost always 802.11ac (Wi-Fi 5). 802.11n and 802.11ax are the dual-band options.

Performance technologies

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Frequency Bands

2.4 GHz

5 GHz

6 GHz (Wi-Fi 6E / Wi-Fi 7)

The 6 GHz band adds many wide (up to 160 MHz) channels with almost no legacy congestion, ideal for AR/VR and dense offices - at the cost of the shortest range. Only 6E/7 clients can use it.

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Wireless Security Protocols

Know this progression from weakest to strongest - questions frequently ask which protocol to avoid and which to deploy now.

Why WPA3 beats WPA2

• SAE (Simultaneous Authentication of Equals) replaces the PSK 4-way handshake and blocks offline dictionary attacks on captured handshakes.
• Forward secrecy means a later password compromise cannot decrypt previously captured sessions.
• Enhanced Open (OWE) encrypts traffic on open guest networks without a password.
• 802.1X/RADIUS ties enterprise logins to individual user credentials, so revoking one account does not require changing a shared key.

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Wireless Configuration

SSID (Service Set Identifier)

• The broadcast network name, up to 32 characters.
• Hiding the SSID is not real security - scanners still see it; it only declutters the network list.

Channel selection

• 2.4 GHz: pick 1, 6, or 11 to avoid co-channel interference.
• 5/6 GHz: pick any clear non-overlapping channel; a Wi-Fi analyzer shows the least-used one.

Access point placement

• Mount centrally and high (ceiling) for even coverage.
• Keep 15-20% cell overlap so clients roam without dropping.
• Set adjacent APs to different non-overlapping channels so they do not interfere.
• Avoid microwaves, large metal objects, and water pipes that attenuate signal.

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Choosing a Band in Practice

Dual-band routers let clients pick 2.4 GHz or 5 GHz, and the exam tests when each is correct. The trade-off is range versus throughput: lower frequencies travel farther and bend around walls, while higher frequencies carry more data but fade quickly. A smart thermostat in a far bedroom belongs on 2.4 GHz, where its modest bandwidth need is easily met and the longer range keeps it connected. A laptop streaming 4K video in the same room as the access point belongs on 5 GHz or 6 GHz, where the extra channels and width deliver the speed without contending with microwaves and Bluetooth.

Many vendors call automatic steering between bands band steering, but candidates should still understand the manual logic behind it.

Interference, Channels, and Overlap

The reason only channels 1, 6, and 11 are usable together in the 2.4 GHz band is that each Wi-Fi channel is about 20 MHz wide while channels are spaced only 5 MHz apart, so adjacent channels overlap and bleed energy into each other. Two access points on channels 1 and 3 will interfere; two on channels 1 and 6 will not. This is co-channel and adjacent-channel interference, and a Wi-Fi analyzer app visualizes it as overlapping bell curves on a spectrum chart.

In a multi-floor office, a tech assigns 1, 6, and 11 in a repeating pattern so no two neighboring cells share or overlap a channel, the same way a cellular network reuses frequencies.

A Wireless Security Scenario

A small business reports that guests on the open lobby Wi-Fi can see each other's traffic and that the back-office network shares the same password printed on a sticker. Two fixes apply. First, move the staff network to WPA3-Personal (or WPA2 if hardware is older) with a strong passphrase that is not posted publicly, because a shared, visible key is effectively no security. Second, enable WPA3 Enhanced Open (OWE) on the guest network so each guest's traffic is individually encrypted even without a password, and place guests on a separate VLAN/SSID so they cannot reach internal resources.

The exam rewards recognizing that hiding the SSID or shortening lease times does nothing to fix weak encryption.