Wireless Network

Question 1

What are wireless networks (WLANs)?

Answer 1

Networks that transmit signals through the air via RF (radio frequency) waves.

Question 2

What is the wireless spectrum?

Answer 2

The frequency range of electromagnetic waves used for data and voice communication.

Question 3

What frequency ranges does the wireless spectrum span?

Answer 3

Between 9 kHz and 300 GHz.

Question 4

What is RFID?

Answer 4

A technology that uses electromagnetic fields to store data on a small chip in an RFID tag.

Question 5

How is NFC different from RFID?

Answer 5

NFC is a form of RFID that transfers data wirelessly over very short distances.

Question 6

What is Z-Wave used for?

Answer 6

A smart home protocol for managing wireless connections and controlling data transmission between devices.

Question 7

What is ZigBee designed to handle?

Answer 7

Small amounts of data for IoT devices.

Question 8

What is Bluetooth technology?

Answer 8

A technology that unites separate entities under a single communication standard.

Question 9

What does ANT+ technology do?

Answer 9

Gathers and tracks information from sensors in devices like heart rate monitors and GPS devices.

Question 10

What is the primary use of IR technology?

Answer 10

To collect data through various sensors.

Question 11

What is signal propagation?

Answer 11

The way in which a wave travels from one point to another.

Question 12

What does LOS stand for in wireless communication?

Answer 12

Line-of-sight.

Question 13

What is attenuation?

Answer 13

The weakening of a signal as it moves away from the transmission source.

Question 14

What is fading in wireless signals?

Answer 14

The gradual decrease in energy of a signal due to obstacles.

Question 15

What is interference in wireless communications?

Answer 15

Electromagnetic waves that can disrupt wireless signals.

Question 16

What does SNR stand for?

Answer 16

Signal-to-noise ratio.

Question 17

What is refraction in the context of signal propagation?

Answer 17

The alteration of a wave’s direction, speed, and wavelength as it travels through objects.

Question 18

What are the notable Wi-Fi standards?

Answer 18

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

Question 19

What is channel bonding?

Answer 19

The process of combining two adjacent 20-MHz channels to create a 40-MHz channel.

Question 20

What does MIMO stand for?

Answer 20

Multiple input-multiple output.

Question 21

What is MU-MIMO?

Answer 21

Multiuser MIMO, which allows multiple antennas to service multiple clients simultaneously.

Question 22

What is OFDMA?

Answer 22

Orthogonal Frequency Division Multiple Access, supporting efficient multiuser functionality.

Question 23

What is the purpose of CSMA/CA in WLANs?

Answer 23

To access a shared medium while avoiding collisions.

Question 24

What is the role of an access point (AP)?

Answer 24

To connect wireless clients to a LAN and act as an Internet gateway.

Question 25

What is SSID?

Answer 25

Service set identifier, a unique character string identifying an access point.

Question 26

What is the purpose of a site survey?

Answer 26

To assess client requirements and coverage areas for reliable wireless connectivity.

Question 27

What is the default security of the 802.11 standard?

Answer 27

No security.

Question 28

What does WPA stand for?

Answer 28

Wi-Fi Protected Access.

Question 29

What is MAC filtering?

Answer 29

A security measure that prevents the AP from authenticating devices not listed by MAC address.

Question 30

What is war driving?

Answer 30

Searching for unprotected wireless networks by driving around with a configured laptop.

Question 31

What is an evil twin attack?

Answer 31

A rogue access point that poses as an authorized AP.

Question 32

What is a remote wipe?

Answer 32

A feature allowing administrators to remove access permissions from a device remotely.

Question 33

What is the purpose of a captive portal?

Answer 33

To control guest access to a network.

Question 34

Fill in the blank: The identifier that allows wireless clients to roam freely from AP to AP is called _______.

Answer 34

ESSID

Question 35

What is war chalking?

Answer 35

Hackers draw symbols with chalk on the sidewalk or wall near a vulnerable AP to make it known to other hackers ## Footnote War chalking is a way for hackers to signal the presence of unprotected wireless networks.

Question 36

What is an evil twin in wireless networks?

Answer 36

A rogue AP planted in a network’s geological area to pose as an authorized AP ## Footnote This technique is used to intercept sensitive data from unsuspecting users.

Question 37

What does a WPA attack involve?

Answer 37

Interception of the network keys communicated between stations and APs ## Footnote This is also referred to as WPA cracking.

Question 38

What is a WPS attack?

Answer 38

Cracking a PIN in order to access an AP's settings ## Footnote The PIN can be easily cracked through a brute force attack.

Question 39

What are the two types of software tools you should have for wireless network management?

Answer 39

* Spectrum analyzer * Wireless analyzer (Wi-Fi analyzer) ## Footnote These tools help assess signal quality and network availability.

Question 40

What capabilities are common to wireless testing tools?

Answer 40

* Identify transmitting access points, stations, and channels * Measure signal strength from an AP * Indicate the effects of attenuation, signal loss, and noise * Interpret signal strength information * Ensure proper association and reassociation between APs * Capture and interpret traffic * Measure throughput and assess data transmission errors * Analyze characteristics of each channel ## Footnote These capabilities are essential for effective wireless network management.

Question 41

What is one common pitfall to avoid when a Wi-Fi client cannot connect to the AP?

Answer 41

Wrong SSID ## Footnote Other pitfalls include encryption protocol mismatch, incorrect passphrase, and static channel utilization.

Question 42

What is a common cause of slow Wi-Fi connections?

Answer 42

Insufficient wireless coverage ## Footnote Additional causes include RF attenuation, interference, and channel overlap.

Question 43

What does CDMA stand for?

Answer 43

Code Division Multiple Access ## Footnote It uses spread-spectrum techniques to multiplex multiple signals within a single channel.

Question 44

What is LTE in mobile communications?

Answer 44

Long Term Evolution, a 4G Wireless communications standard designed to provide up to 10 times 3G network speeds ## Footnote LTE is pivotal for the advancement of mobile broadband.

Question 45

What does HSPA+ provide in terms of network speeds?

Answer 45

Theoretical download speeds of 168 Mbps and uplink of 22 Mbps ## Footnote HSPA+ is developed to offer speeds comparable to LTE networks.

Question 46

What is the standard defining 3G wireless technology?

Answer 46

International Mobile Communications, or IMT 2000 ## Footnote This standard is crucial for defining broadband network wireless services.

Question 47

What is the maximum download speed provided by 4G technology?

Answer 47

100 Mbps ## Footnote 4G technology is the successor to 3G and significantly enhances mobile internet speeds.

Question 48

What is Edge in mobile communications?

Answer 48

Enhanced Data GSM Evolution, providing download speeds of 384 Kbps ## Footnote Edge is a key technology in the evolution of mobile data services.

Question 49

Which device lets you determine all frequencies within a scanned range that are present in a specific environment?

Answer 49

Spectrum analyzer ## Footnote This device is essential for assessing the quality of wireless signals.

Question 50

What should you be able to do after completing the lesson?

Answer 50

* Describe characteristics of wireless transmissions * Explain 802.11 standards and innovations * Plan a Wi-Fi network * Secure a Wi-Fi network * Troubleshoot a Wi-Fi network ## Footnote These skills are critical for effective wireless network management.