Wireless Networking

Question 1

PoE

Answer 1

Power over Ethernet
PoE: IEEE 802.3af
PoE+: IEEE 802.3at
PoE++: IEEE 802.3bt

Question 2

RTS/CTS

Answer 2

Request to send
Clear to send

Question 3

CSMA/CA

Answer 3

Carrier sense multiple access/collision avoidance
Wireless device listens in on the wireless medium to see if another is currently broadcasting data
If so it waits a random amount of time before retrying

Question 4

Bands

Answer 4

Contiguous range of frequencies that is usually divided up into discrete slices called channels
2.4ghz (overlapping)
5ghz (no overlapping)
6ghz

Question 5

Wireless standards

Answer 5

802.11a
802.11b
802.11g
802.11n
802.11ac
802.11ax

Question 6

802.11a

Answer 6

First to use 5ghz band
Speeds up to 54mbps
Actual speeds no more than 25mbps
Theoretical range of 150 feet

Question 7

802.11b

Answer 7

First standard to take off
Up to 11mbps
Actual around 4-6 mbps
Max range 300ft (ideal conditions)
2.4ghz ISM band
High likelihood of interference

Question 8

802.11g

Answer 8

Combines best of a and b
Up to 54mbps
300ft range
2.4ghz ISM band
Backwards compatible to 802.11b

Question 9

802.11n

Answer 9

WiFi 4
Multiple In/Multiple Out (MIMO)
Up to 600mbps (practical speeds 100+mbps)
300+ft
Supports dual band (2.4ghz and 5ghz)

Question 10

802.11ac

Answer 10

WiFi 5
Only uses 5ghz band
Multiuser MIMO (WAP can broadcast to multiple users simultaneously)
Supports dual band operation
Some WAP support tri band operation (two 5ghz signals)
1+gbps speed
300+ft

Question 11

802.11ax

Answer 11

High efficiency wireless (HEW)
WiFi 6 (or 6E for extended)
Can use both 2.4ghz and 5ghz bands
Newer devices support 6ghz as well
Max of 9+gbps speeds
300+ft

Question 12

Long ranged fixed wireless

Answer 12

Uses directional antennas
Point to point connection
Provide remote buildings network access up to several miles away from main building without running cables