8A Flashcards
Wireless networks make use of wireless data connections to transmit and receive data through _______.
radio waves
A wireless network can join ________ devices through radio waves
two or more
Since wireless networks relies on _________, it reduces the need to depend on wires.
spread-spectrum
What are the three terminologies used in wireless networks…?
- Access point
- Network nodes
- Service set identifier
What does “WAP” stand for?
Wireless Access Point
How does WAP work?
When the radio frequency is applied to the Wireless Access Point (WAP) antennas, this creates an electromagnetic field which is then radiated through space to be received by the user device.
The most important element in a wireless network is the _______ device.
Access Point
What is an access point?
An access point is a device that creates a wireless local area network (WLAN), usually in an office or large building.
How does an access point work?
An access point connects to a wired router or switch via an Ethernet cable and transmits a Wi-Fi signal to a designated area.
What does “WLAN” stand for?
Wireless Local Area Network
What does “WAN” stand for?
Wide Area Network
What does “NIC” stand for?
Network Interface Card
In LANs and wide area networks (WANs), _______ is a device that performs a specific function.
a network node
Under the IEEE 802.11 wireless networking standard, a “service set” refers to….?
a collection of wireless networking devices with the same parameters
Because multiple WLANs can coexist in one airspace, each WLAN needs a unique name—this name is the________ of the network.
service set identifier (SSID)
The SSID is the identifier (name) that tells you what?
which service set (or network) to join
What are the types of wireless networks?
WWAN, WLAN, WPAN, WMAN, hybrid and wireless ad
hoc.
What does WWAN stand for?
Wireless Wide Area Network
What does WWAN provide?
This type covers wireless networks over a wide area.
How does WWAN work?
This is achieved by wirelessly connecting coverage cells to provide services to an expanded geographical location.
The WWAN is typically used to cater to the ________ market through cellular service providers
smartphones’
WWAN’s coverage is of large service areas such as _________________.
cities, region or even countries
Commonly deployed WWAN technologies include…?
GSM/GPRS/EDGE, CDMA2000, UMTS/HSDPA and CDMA EV-DO
This is different from a normal Wi-Fi connection because in a Wi-Fi setting, individuals can enjoy wireless services through any hotspot. However, with the WWAN, specific handheld devices need to be…?
specifically provisioned (or subscribed) to gain access to any service provider’s network
WLAN is also known as?
LAWN (Local Area Wireless Network)
What is WLAN?
(WLAN) is a wireless computer network that links two or more devices using a wireless distribution method within a limited area such as a home, school, computer laboratory, or office building.
WLAN can be constructed through any kind of wireless network protocol, but the most common way of connection is through…?
Wi-Fi for distances up to 100 meters
Most modern WLANs are based on _______ standards, marketed under the Wi-Fi brand name.
IEEE 802.11 standards
The WLAN support can range from _______ devices.
two or more
The WLAN caters to devices such as…?
laptops, mobile phones, tablets computers, gaming console, internet audio system, and internet-powered home devices and appliances
What are Single Access Point WLANs?
Client devices use this name to identify and join the wireless network. In simple terms, it’s the name of the Wi-Fi network that you look for to join your device to.
What are the SSIDs found in WLAN?
single access point WLANs, basic service set identifiers (BSSDs), and extended service set identifiers (ESSIDs).
What does BSSID stand for?
Basic Service Set Identifier
What do BSSIDs do?
BSSIDs identify access points and their clients
Each access point has its own basic service set (BSS), and the MAC address is used as the…?
ID of a BSS (BSSID)
What is an ad-hoc network?
a network that forwards traffic from node to node, has no access point.
What does ESSID stand for?
Extended Service Set Identifier
An extended basic service set (ESS) consists of…?
all the BSSs in the network
Access points in an ESS are connected by a __________.
centralized distribution system
This is the type of system we have at Dolan Hall; every classroom has an AP that broadcasts our “LWS” ESSID or just simply SSID. What type of system is this?
Extended Service Set Identifier (ESSID)
What does WPAN stand for?
Wireless Personal Area Network (WPAN)
What is WPAN?
This personal area network provides a wireless connection to devices that surround an individual’s personal space.
In a typical network, the WPAN makes use of a technology that enables wireless communication within a range of _____________.
10 meters
WPAN is a ____________ network.
short range
What are two common examples of WPAN?
infrared and bluetooth
What are the benefits of using WPAN?
- Provides short-range communication
- low cost
- provides a connected communication of various devices in people’s personal space.
What does WMAN stand for?
Wireless Metropolitan Area Network (WMAN)
What is WMAN?
A wireless network that is intended to cover an area that ranges around 31 miles, or 50 kilometers
WMAN is also referred to as?
Base Area Network (BAN) or a Campus Area Network (CAN).
WMAN allows multiple locations or buildings to stay connected within any ____________ area.
metropolitan
WMAN does not require a network of cables running from one
building to the next. Instead, it relies on…?
strong radio waves or infrared light to transmit data
Due to its strong wireless connectivity, WMAN is often used as a what?
backup for wired networks.
Usually, the WMAN falls in between _____ and ______. Generally, this network is set up in a way that provides a connection between various points of LANs.
WWAN and WLAN
The main goal of WMAN is to provide…?
wireless connection between two independent and fully functional LAN nodes.
The only downside to this network is that it is easily…?
Attacked. Since the WMAN covers a wide range of geographical locations, it provides hackers with countless opportunities to hack the networks.
What is a hybrid network?
In a standard hybrid network, there is a hybrid access point that relies on wireless as well as wired signals. A usual hybrid router transmits a Wi-Fi signal, but it also contains ports that can be connected to any
digital subscriber line (DSL) modem or cable through Ethernet cables.
The most common network configuration for a hybrid network is?
The most common one is where every wired device is plugged into the hybrid router’s Ethernet ports.
The hybrid network is popular due to its…?
Accessibility and cost-saving factors.
______ is the biggest concern with hybrid networks.
Security
What is a wireless ad hoc network?
the wireless ad Hoc network is a kind of impromptu, on-demand network that works from device to device. In this network setting, one can wirelessly connect one device to another without first connecting to a wireless router or access point.
What does “ad hoc” mean?
ad hoc means something improvised or a makeshift device
Since an ad hoc wireless network can sustain itself without any existing infrastructure, it is decentralized and regarded as a ______ network.
peer-to-peer network
An ad hoc wireless network does not rely on what?
It does not rely on a wireless router or central Access Point to transmit data from one point to another.
Since Ad hoc networks can be created in any environment and under any circumstances, this quality makes them ideal for whose usage?
- larger organizations
- Small and mid-size enterprises
- ordinary personal usage.
What are some wireless advantages?
- Increased mobility and collaboration
- Roam without losing your connection
- Connect hard to reach areas
What are some wireless disadvantages?
- Speed
- Reliability
- Security
- Reduced management control
What are some examples of devices that use WPAN?
Peripheral and hand-held devices such as personal digital assistants (PDAs), smart phones and tablet personal computers (PCs)
What is WPAN’s range capabilities?
Depends on the wireless router’s capabilities, access point or the device itself, but it is usually restricted to a house or small office.
WPAN can be created using…?
Wi-Fi, Bluetooth, or infrared or any similar wireless technologies.
In some cases for WPAN, one of the Internet enabled/powered devices acts as an __________ and provides network and Internet access to other devices.
access point
Wi-Fi is a technology based on the _________ suite of standards
IEEE 802.11
Based on the IEEE 802.11 suite of standards that uses _____________
to extend wired Ethernet-based LANs to Wi-Fi-enabled devices.
radio frequencies (RF)
Wi-Fi uses ____ to communicate between endpoint devices
and the LAN.
IP
A Wi-Fi connection is established using a _____________ that is connected to the network and allows devices to access the internet.
wireless router
One disadvantage of Wi-Fi is that it may be prone to ___________ depending on the radio frequency (RF) environment it’s operating in.
interference
What are Wi-Fi’s two frequencies?
2.4GHz and 5GHz
Wi-Fi is best for ___________________ requiring higher data rate network connections (1Mbps-1Gbps)
LAN video, e- mail, and web applications
IEEE 802.15.1-
Bluetooth
IEEE802.15.4 -
ZIGBEE
IEEE802.15.7 -
LI-FI
IEEE 802.16 -
WIMAX
What is bluetooth?
Bluetooth is a standard for the short-range wireless interconnection of mobile phones, computers, and other electronic devices.
Bluetooth sends and receives radio waves in a band of ___ different frequencies (channels)
79
Bluetooth is centered on ___ GHz
2.4 GHz
Bluetooth’s __________________ have very low power consumption and are more secure than wireless networks that operate over longer ranges, such as Wi-Fi.
short-range transmitters
Bluetooth is a global 2.4 GHz PAN for __________________________.
short-range wireless communication
What is often enabled with Bluetooth?
Device-to-device file transfers, mobile credentials, wireless speakers, and wireless headsets
What is ZigBee?
ZigBee is a 2.4 GHz mesh LAN protocol.
What was ZigBee developed for?
For a suite of high-level communication protocols used to create personal area networks with small, low-power digital radios.
ZigBee devices transmit data over long distances by passing it through a….?
Mesh network of intermediate devices to reach more distant ones.
ZigBee networks have a defined rate of ____ kbps and are secured by
____-bit symmetric encryption keys.
250 kbps
128-bit
ZigBee is typically used in low-data-rate applications that require what?
- High scalability
- Long battery life
- Secure networking
How is ZigBee different than WiFi and Bluetooth?
It is simpler and less expensive
What is ZigBee commonly used for?
Home, building and industrial automation applications, such as controlled lighting and thermostats, home energy monitors, smart metering, medical device data collection, traffic management systems and other low-power, low- bandwidth needs.
What does LED stand for?
Light Emitting Diode
What is Li-Fi?
Li-Fi is a form of visual light communication that uses light waves from Light Emitting Diodes (LEDs) for high-speed wireless communication.
Li-Fi is used to exchange data quickly and securely at a much
_________ level compared to Wi-Fi.
lower power
Li-Fi can’t penetrate ______________, which makes it more secure, but also means a Li-Fi network in a building would need multiple transmitter LEDs, so a mobile user could experience seamless wireless coverage as they move between the illumination areas of each LED
solid materials
When a constant current source is applied to an LED, it emits a constant stream of ________ observed as visible light. When this current is varied slowly, the bulb dims up and down. Since the bulbs are
semiconductors, the current and optical output can be modulated at extremely high speeds that can be detected by a photodetector device and converted back to electrical current.
photons
Li-Fi has fewer interference issues than RF technology, making it ideal for _____________ where Wi-Fi may fall short.
dense environments
What is WIMAX?
Designed for long-range networking (spanning miles or kilometers) as opposed to local area wireless networking.
What does CSMA/CA stand for?
Carrier Sense Multiple Access/Collision Avoidance
What is CSMA/CA?
CSMA/CA is a network contention protocol that listens to a network to avoid collisions, unlike CSMA/CD that deals with network transmissions once collisions have been detected.
How does CSMA/CA contribute to network traffic?
CSMA/CA contributes to network traffic because, before any real data is transmitted, it must broadcast a signal onto the network in order to listen for collision scenarios and to tell other devices not to broadcast.
What is a wireless access point?
A wireless access point is an interface between a wired and wireless network.
Wired network uses the ___________ while the wireless network uses the ___________.
Ethernet-standards
IEEE802.11 or Wi-Fi standards
An access point uses ___________ for connectivity.
radio signals
The most important element in a wireless network is the _________.
access point
What are the four access points?
- Autonomous Access Point
- Multifunction Access Point
- Lightweight Access Point
- Rogue Access Points
This was the original type of access point and ranged from one to ten access points across the network.
Autonomous Access Point
Autonomous access points have all the software required to manage the ____________ with no need for additional controllers or switches.
WLAN processes
A multifunction access point is the combination of multiple devices, these devices are…?
an access point, a regular ethernet, switch, a router and sometimes a modem
What is an example of a multifunction access point?
a wireless router
What does LWAP stand for?
Lightweight Access Point
A LWAP works as the client of the ____________.
Wireless LAN controller (WLC)
Technically a controlled access point is known as…?
LWAP
What is a rogue access point?
A rogue access point is a wireless access point that has either been installed on a secure company network without explicit authorization from a local network administrator or has been created to allow a
hacker to conduct a man-in-the-middle attack.
Why do rogue access points of the first kind pose a security
threat to large organizations with many employees?
because anyone with access to the premises can install (maliciously or non- maliciously) an inexpensive wireless router that can potentially allow access to a secure network to unauthorized parties.
What do rogue access points of the second kind target?
networks that do not employ mutual authentication (client-server server- client) and may be used in conjunction with a rogue RADIUS server, depending on security configuration of the target network.
