Wireless Networok Technologies 2.2 Comptia a+ 220-1201

What is the IEEE standard identification for Wi-fi 1?

802.11b

What is the IEEE standard identification for Wi-fi 2

802.11a

What is the IEEE standard identification for Wi-fi 3

802.11g

What is the IEEE standard identification for Wi-fi 4

802.11n

What is the IEEE standard identification for Wi-fi 5

802.11ac

What is the IEEE standard identification for Wi-fi 6

802.11ax

What is the IEEE standard identification for Wi-fi 7

802.11be

What is the frequency band for Wi-fi 1

802.11b = 2.4 GHz

What is the frequency band for Wi-fi 2

802.11a = 5GHz

What is the frequency band for Wi-fi 3

802.11g = 2.4Ghz

What is the frequency band for Wi-fi 4

802.11n = 2.4GHz & 5GHz

What is the frequency band for Wi-fi 5

802.11ac = 5GHz

What is the frequency band for Wi-fi 6

802.11ax = 2.4GHz & 5GHz

What is the frequency band for Wi-fi 7

802.11be = 2.4, 5, & 6 GHz

What is the max theoretical speed of Wi-fi 1

11Mbps - 802.11b

What is the max theoretical speed of Wi-fi 2

54Mbps - 802.11a

What is the max theoretical speed of Wi-fi 3

54 Mbps - 802.11g

What is the max theoretical speed of Wi-fi 4

802.11n - 600 Mbps

What is the max theoretical speed of Wi-fi 5

802.11ac - ~3.5 Gbps

What is the max theoretical speed of Wi-fi 6

802.11ax - ~9.6 Gbps

What is the max theoretical speed of Wi-fi 7

802.11 be - ~46 Gbps

What does MIMO stand for?

Multi input multi output

What does LAN and WLAN stand for ?

Local area network - networks that are near you

Wireless local area network 

What are frequencies and what do they do?

determine range and speed and interference levels.

the number of oscillations or cycles of a signal per second

measured in Hertz (Hz)

It plays a crucial role in determining how data is transmitted over communication channels, such as radio waves, optical fibers, or electrical signals.

What is IEEE 802.11

Wi-fi

What are Access points?

a device that lets wireless devices connect to LAN acts as a bridge between wireless devices and their network

What is infastructure mode?

Refered to as BSS (basic service set), each client device is configured to connect to the network via access point (AP)

What is BLE?

Bluetooth low energy - for small battery powered devices that transport info infrequently, remains in low power state until connection is innitiated. 

What is Bluetooth 5?

Newest version of bluetooth,range up to 800 ft, twice the speed of Bluetooth 4

What is RFID?

Radio Frequency ID - Means identifying and tracking objects using tags, tags can be unpowered(passive) or powered (active)

What is NFC?

Near Field Commuications - peer to peer ver. of RFID, works up to 6 inches

What are channels?

Series of smaller ranges split from a wireless frequency, each has its own radio frequency, size of channel is determined by frequency bands and access points.

Describe the 3 wireless frequency bands?

2.4 - Better through solid services, easily conjested, longest signal range

5 - Not good with solids, smaller max range, supports indiviual channels higher data rates at shorter range

6 - worst with solid surfaces, fastest option, less congestion, restriction of power output. 

Describe the attributes of 802.11a

uses 5GHz only

data encoding allows maximum drive of 54 Mbps

divide into 3 overlapping channels each 20 MHz wide

Must implement dynamic frequency selection to prevent wi-fi signals from interfering with nearby radar and satellite installations

Describe the attributes of 802.11 b/g

uses 2.4 GHz

divided into 14 channels, 5MHz intervals from 2412 - 2484

Describe the attributes of 802.11b

channels overlap a lot, causes a lot of interference

uses DSSS

spreads signal across wider channel (22mhz)

What is DSSS?

Direct sequence spread spectrum - Modulation

What is modulation?

Process of modifying a radio wave so it can carry data

What is OFDM?

Orthogonal Frequency Division

Describe the attributes of long-range fixed wireless

low cost, unregulated, point to point computer network connection, high grain, can transmit up to 30 miles as long as unobstructed. often on top of tall buildings.

Licensed vs Unlicensed frequency

-purchased from FCC

-operator used public frequency band (900, 2.4, 5 MHz) interference is a risk 

What are the 3 main components of Long-Raged Fixed Wireless?

Transmit power - basic strength of radio (dBm)

Antenna Gain - amount that a signal is boosted by directionally (focus’ signal in single direction)

Effective isotropic radiated power (EIRP - Sum of transmit power and gain expressed in dBm

Describe low frequencies

Stricter power limits than higher

Higher EIRP’s are allowed for highly directional antennas

Describe Wi-fi 5

-works in 5GHz band

-allows up to 8 streams, mostly 4×4

-single stream over 80MHz channel has nominal rate of 433 Mbps

-allows wider 80&160 MHz bonded channels 

-AP points are marked using AC values

What is a nominal rate?

a data type that can only take on certain values within a set range

What is MU-MIMO?

Multi user multi input multi output

in basic 802.11 mode bandwidth is spread between all stations

AP can talk with 1 station at a time, multiple requests in a queue

Describe Wi-fi 6

-from 80 Mbps to 600

works in 2,4 & 5GHz bands

-Wi-fi 6e - more support for 6GHz bands

-Supports up to 8 clients & uplink MU-MIMO

-allows MU-MIMO clients to send data over AP at same time. 

What is OFDMA?

Orthogonal Frequency Division Access

-improves simultaneous connection

-works alongside MU-MIMO

Improves client density

Sustain high data rates when multiple stations are at the same AP (Access point)

Describe WI-fi 7

-supports all GHz bands

-Uses 320 MHz wide channels when 6GHz range

-Supports MLO 

-Sends data over multiple bands or channels 

-Reduces latency and improves throughput

What is MLO?

Multi-Link operation - allows devices to connect and send data over multiple bands (2.4, 5, 6) or channels.

Describe an MRU

-Multi Resource Unit

-smaller broken channels of channel 6 

-can be all different sizes’

-AP allocates MRUs to devices based on data requirements

Describe a Wi-fi analyzer

-hardware or software (can be installed)

-Records stats for Access Points

-determines best layout (channel), measures signal strength of networks

How is signal strength measured?

decibels

1 mW = 0 dBm

negative dBm = fractional mW

What is the signal to noise ratio?

-strength of data signal in comparison to background noise 

-Background noise is meaured in dBm 

-the closer to 0, the worse it is

Ex. -65dBm - 90dBm SNR = 25 dB

What is SSID?

Service set identifier

identify infrastructure configured through access point

up to 32 bytes in length

use only ASCII for max controllability 

when configuring, to ap, choose same or different network names for both bands.