Week 5

Question 1

Baud rate

Answer 1

A measurement of how many bits can be passed across a phone line in a second

Question 2

Broadband

Answer 2

Any connectivity technology that isn’t dial up internet

Question 3

T-carrier technologies

Answer 3

Originally invented by AT&T in order to transmit multiple phone calls over a single link

Question 4

How fast can a T1 line transmit data?

Answer 4

1.54 Mb/s

Question 5

Cable modem termination system (CMTS)

Answer 5

Connects lots of different cable connections to an ISPs core network

Question 6

Optical network terminator (ONT)

Answer 6

Converts data from protocols the fiber network can understand, to those that more traditional, twisted-pair copper networks can understand

Question 7

Wide area network

Answer 7

Acts like a single network, but spans across multiple physical locations

Question 8

What layer do WANs draw a lot from?

Answer 8

Data link layer

Question 9

Area between site and an ISP

Answer 9

Local loop

Question 10

802.11 families

Answer 10

Make up the set of standards for WiFi

Question 11

What kind of waves do wireless networks communicate through?

Answer 11

Radio

Question 12

Frequency band

Answer 12

A certain section of the radio spectrum that’s been agreed upon to be used for certain communications

Question 13

What radio frequency does FM radio operate under in North America?

Answer 13

Between 88 and 108 MHz

Question 14

What are the common Wi-Fi bands?

Answer 14

2.4 GHz and 5 GHz

Question 15

What are the most common 802.11 specifications IT support deals with?

Answer 15

802.11b, 802.11a, 802.11g, 802.11n, 802.11ac

Question 16

What layers do 802.11 standards typically deal with?

Answer 16

Physical and data link layers

Question 17

Frame control field

How many octets?

Answer 17

Contains fields describing how the 802.11 frame should be processed

2

Question 18

Duration field

Octets?

Answer 18

Specifies how long the frame is, thereby letting receiver know how long to listen to the transmission

2

Question 19

How many address fields in a 802.11 frame?

Answer 19

4

Question 20

Wireless access point

Answer 20

A device that bridges the wireless and wired portions of a network

Question 21

What do each of the address fields in an 802.11 frame contain

Answer 21

Source MAC address, destination MAC address, Transmitter address, receiver address

Question 22

Receiver address

Answer 22

MAC address of the device that should receive the frame

Question 23

Transmitter address

Answer 23

MAC address of whatever has just transmitted the frame

Question 24

How long is a single address field

Answer 24

6 octets , because they only contain MAC addresses

Question 25

Where is the sequence field in the 802.11 field located?

Answer 25

Between the transmitter and receiver address field

Question 26

What are the last two fields in the 802.11 frame?

Answer 26

Payload, then frequency checksum value

Question 27

Ad-Hoc network

Answer 27

Wireless network where nodes speak directly to each other

Question 28

Wireless LANS

Answer 28

One or more wireless access points act as a bridge between a wireless and a wired network

Question 29

Mesh networks

Answer 29

Hybrid of ad-hoc and WLAN network

Question 30

Channels

Answer 30

Individual, smaller sections of the overall frequency band used by a wireless network

Question 31

Wired Equivalent Privacy (WEP)

Answer 31

An encryption technology that provides a very low level of privacy

Question 32

How many bits in a WEP encryption key?

Answer 32

40

Question 33

How many bits in WiFi Protected Access?

Answer 33

128

Question 34

What is the most common wireless encryption algorithm? How many bits does its key have?

Answer 34

WPA2 256

Question 35

MAC filtering

Answer 35

You configure your access points to only allow for connections from a specific set of MAC addresses belonging to devices you trust