Chapter 26: Fundamentals of Wireless Nentworks Flashcards
Wired Ethernet and Wi-Fi are based on which two IEEE standards, respectively?
802.3, 802.11
Devices using a wireless LAN must operate in which mode?
Half Duplex
An access point is set up to offer wireless coverage in office. What is the correct 802.11 term for the resulting standalone network?
BSS (basic service set)
What is used to uniquely identify an AP and the basic service set to maintains with its associated wireless clients?
SSID (Service set identifier)
What can be used to provide wireless connectivity to nonwireless device?
Workgroup bridge
What is not needed in a Cisco outdoor mesh network?
Ethernet cabling to each AP
What is the frequency band commonly used for Wi-Fi?
2.5 GHz, 5 GHz
Which of the following are considered to be nonoverlaping channels?
a. 1,2 and 3 in the 2.4-GHz band
b. 1,5 and 10 in the 2.4-GHz band
c. 1,6 and 11 in the 2.4 GHz band
d. 40,44 and 48 in the 5-GHz band
c. 1,6 and 11 in the 2.4 GHz band
d. 40,44 and 48 in the 5-GHz band
What does the area where the AP’s signal is usable called?
BSA (Basic service area) or cell
What is BSSID and what is it for?
BSSID (basic service set identifier) is generated by the AP based on it’s MAC Address and is used to advertise the existence of the BSS to the devices in range.
How can an AP advertise more than one VLAN to it’s clients?
By advertising more than one SSID and mapping every SSID to one VLAN.
What do we call an interconnected APs by switched infrastructure?
ESS (Extended service set)
What do we call the process of a wireless client moving between APs?
Roaming
What is IBSS?
IBSS (independent v
basic service set) is an ad hoc (or on demand) wireless network that is created between two devices without the need for an AP.
What does a wireless repeater do?
A wireless repeater takes the signal it receives and repeats or retransmits it in a new cell area around the repeater.
What is a Workgroup bridge?
WGB is a wireless device that is used to offer wireless connection to devices in network that do not have the possibility to directly connect to a wireless network.
What is an Outdoor Bridge?
Two APs that are wirelessly connected to provide connection between buildings or cities.
In which mode should the AP operate in order to support the use of Outdoor Bridge?
Bridge mode
What is a wireless mesh network?
Multiple APs configured in mesh mode where wireless traffic is bridged from AP to AP, in a daisy-chain fashion, using another wireless channel.
What is the wireless wave frequency?
The number of times the signal makes one complete up and down cycle in 1 second.
What is a Hertz?
It is the most commonly used frequency unit and is nothing other than one cycle per second.
How many Hz in:
a. Kilohertz
b. Megahertz
c. Gigahertz
a. kHz: 1000 Hz
b. MHz: 1000,000 Hz
c. GHz: 1000,000,000 Hz
What is the frequency of Radio (RF)
It is the frequency range between 3 kHz to 300 GHz.
What are the basic Characteristics of 802.11-1997
2.4 GHz: Yes
5 GHz: No
Max Data Rate: 2 Mbps
Note: The original 802.11 standard ratified in 1997
What are the basic Characteristics of 802.11b
2.4 GHz: Yes
5 GHz: No
Max Data Rate: 11 Mbps
Note: Introduced in 1999
What are the basic Characteristics of 802.11g
2.4 GHz: Yes
5 GHz: No
Max Data Rate: 54 Mbps
Note: Introduced in 2003
What are the basic Characteristics of 802.11a
2.4 GHz: No
5 GHz: Yes
Max Data Rate: 54 Mbps
Note: Introduced in 1999
What are the basic Characteristics of 802.11n
2.4 GHz: Yes
5 GHz: Yes
Max Data Rate: 600 Mbps
Note: HT (High throughput), Introduced in 2009
What are the basic Characteristics of 802.11ac
2.4 GHz: No
5 GHz: Yes
Max Data Rate: 6.93 GHz
Note: VHT (Very High throughput), Introduced in 2013
What are the basic Characteristics of 802.11ax
2.4 GHz: Yes
5 GHz: Yes
Max Data Rate: 4x6.93 GHz or 4x802.11ac
Note: High Efficiency Wireless, Wi-Fi6; expected late 2019; will operate in other bands too, as they become available.
