Wifi And Rf Theory

Question 1

What’s the basic transmission rate in the 2.4ghz band

Answer 1

1 or 2 mbps

Question 2

What’s the basic transmission rate in the 5 ghz band

Answer 2

6mbps

Question 3

What’s the basic transmission rate in the 6ghz band

Answer 3

20gbps

Question 4

What is the osi model?

Answer 4

Conceptual model for computing devices.

Question 5

What is wifi also known as?

Answer 5

802.11 protocol

Question 6

What is wifi?

Answer 6

A set of rules that dictate how wireless devices connect to and communicate with each other

802.11 protocol

Question 7

What layers does the wifi model operate in

Answer 7

Layers 1 and 2

Question 8

Layer 1 for wifi

Answer 8

Air is the medium

Conditions are frequency, modulation and transmission type

Question 9

Ieee

Answer 9

Institute of electrical and electronics engineers

Question 10

What transmission rate do management frames get sent on?

Answer 10

Basic transmission rate

Question 11

What is the significance of 802.11 basic transmission rates?

Answer 11

Management frames are sent at this rate

Question 12

Can basic transmission rates be modified?

Answer 12

Yes.

Within router settings

Question 13

How wide are dsss channels

Answer 13

22mhz

Question 14

How wide are ofdm channels?

Answer 14

20mhz

Question 15

What are 2.4ghz non overlapping channels?

Answer 15

1 6 and 11

Question 16

How wide are all 5ghz channels?

Answer 16

20mhz

Question 17

How many non overlapping channels does 5ghz have?

Answer 17

24

Question 18

What is Channel bonding?

Answer 18

Combines channels into wider subcarriers.

Routers detect unused adjacent channels (automatically).

Question 19

Mimo

Answer 19

Multiple input multiple output.

Multiple antennas send data in multiple data streams.

Data is split in between Send and receive antenna

Question 20

What must a device be compatible with for sustained communications?

Answer 20

Frequency
802.11 amendment (a b g n ac …)
Mimo
Polarity

Question 21

What is the basic transmission rate?

Answer 21

Lowest supported rate of all devices on a network

Question 22

What does layer 2 do?

Answer 22

Delivers reliable transmission between two physical nodes.

Question 23

What are the cornerstones of 802.11 analysis?

Answer 23

Mac addresses

Frames

Question 24

MAC address

Answer 24

6 bytes

First 3 bytes = organisationally unique identifier

Last 3= universally administered address

Question 25

What is a frame?

Answer 25

Sef contained independent entities of data carrying sufficient information to be routed from source to destination

Question 26

What addresses does a frame contain?

Answer 26

Source address
Transmit address
Receive address
Destination address

Question 27

What are the three frame types?

Answer 27

Management
Control
Data

Question 28

What’s a management frame

Answer 28

Used to facilitate connections and transmitted at the basic rate

1-2 mbps @ 2.4ghz
6 mbps @ 5 ghz

Question 29

What’s a control frame?

Answer 29

Used to facilitate the exchange of data from higher protocols

Question 30

What’s a data frame?

Answer 30

Contain data from higher layers.

Sent at highest allowable data rates.

Question 31

What are management frame subtypes?

Answer 31

Bacon
Probe request/response

Authentication
Association
Action

Question 32

What are control frame subtypes?

Answer 32

Rts
Cts
Ack

Block ack
Power saving-poll
Cf-end

Question 33

What are data frame subtypes?

Answer 33

Data
Null