CompTIA A+ 220-1201 (2.2 - Wireless Network Technologies)

Wireless technologies

• IEEE standards

- Institute of Electrical and Electronics Engineers

- 802.11 committee

- Everyone follows these standards

• Also referenced as a generation

- 802.11ac is Wi-Fi 5

- 802.11ax is Wi-Fi 6 and Wi-Fi 6E (extended)

- 802.11be is Wi-Fi 7

- Future versions will increment accordingly

802.11 technologies

• Frequencies

- 2.4 GHz, 5 GHz, and 6 GHz - Sometimes a combination

• Channels

- Groups of frequencies, numbered by the IEEE

- Frequencies are managed by governing entities

- Using non-overlapping channels would be optimal

• Bandwidth

- Amount of frequency in use

- 20 MHz, 40 MHz, 80 MHz, 160 MHz, etc.

Bluetooth

• Remove the wires

- Headsets, speakers, keyboards / mice

• Uses the 2.4 GHz range

- Unlicensed ISM

(Industrial, Scientific and Medical) band

- Same as 802.11

• Short-range

- Most consumer devices operate to about 10 meters

RFID (Radio-frequency identification)

• It's everywhere

- Access badges

- Inventory/Assembly line tracking

- Pet/Animal identification

- Anything that needs to be tracked

• Radar technology

- Radio energy transmitted to the tag

- RF powers the tag, ID is transmitted back

- Bidirectional communication

- Some tag formats can be active/powered

NFC (Near field communication)

• Two-way wireless communication

- Builds on RFID, which is mostly one-way

• Payment systems - Major credit cards, online wallets

• Bootstrap for other wireless

- NFC helps with Bluetooth pairing

• Access token, identity "card"

- Short range with encryption support