Wireless Networks

CompTIA+ Network Learning

Wireless Networks

Networks that extend the physical network into the wireless domain, allowing users to connect and access the internet wirelessly.

WLANs

Stands for Wireless Local Area Networks, which are wireless networks that cover a specific area, such as a campus, building, or outdoor space.

802.11 or WiFi

The standard for wireless networking, which includes various standards such as 802.11a, b, g, n, ac, and ax.

Ad-Hoc Mode

A wireless network configuration where devices communicate directly with each other without the need for a centralized access point.

Infrastructure Mode

A wireless network configuration where devices communicate through a centralized access point or router, resembling a star topology.

Wireless Access Point (WAP)

A device used to extend a wired network into the wireless domain, allowing wireless devices to connect to the network.

Wireless Router

A combination device that acts as a wireless access point and a router, providing gateway and base station functions for wireless networks.

Ad Hoc Mode (IBSS)

A wireless network configuration where devices form an independent basic service set, communicating in a peer-to-peer manner without access to the internet or local area network.

Basic Service Set (BSS)

A wireless network configuration where devices connect to a wireless access point, enabling access to the internet and local area network.

Extended Service Set (ESS)

A wireless network configuration where multiple access points work together to provide coverage over a larger area, allowing seamless connectivity throughout the network.

Extended Service Set (ESS)

A network configuration that uses multiple access points to provide good coverage across a large area, such as a building or college campus.

Mesh Topology

A network configuration that combines multiple wireless technologies, such as microwave, cellular, and Wi-Fi, to create a single coherent network.

Access Point Placement

The careful planning and placement of access points in order to ensure proper coverage and avoid interference in a wireless network.

Channel Overlapping

The practice of ensuring that adjacent access points in a wireless network do not use the same channel frequency to prevent interference and signal drops.

Heat Map

A visual representation of wireless coverage areas in a building or area, showing areas of strong and weak signal strength.

Range Extender

A device that amplifies and extends the reach of a wireless signal, allowing for increased coverage in areas with distance limitations.

Antenna Selection

The process of choosing the appropriate antenna for a wireless network based on factors such as coverage distance, coverage pattern, and environmental conditions.

Omnidirectional Antenna

A type of antenna that radiates power equally in all directions, providing coverage in a 360-degree pattern.

Omnidirectional antenna

An antenna that radiates and receives signals in all directions, providing full coverage to a specific area.

Unidirectional antenna

An antenna that focuses all its power in one particular direction, allowing for longer distance connections between buildings or sites.

Yagi antenna

A type of unidirectional antenna commonly used to connect buildings or sites over a longer distance by pointing directly at the target location.

Directional antenna

An antenna that shapes the direction of the wireless signal, allowing for focused coverage in a specific area and preventing signal leakage.

Floor plan

A visual representation of a building's layout, used to determine the placement of antennas for optimal coverage.

Omnidirectional antenna in wireless access points

An internal antenna that sends and receives data in all directions, providing equal power in all directions for connecting to wireless devices.

External antenna

An antenna that can be replaced or changed to increase signal strength and coverage area.

Parabolic antenna

A type of unidirectional antenna with a curved dish shape, often used for microwave and satellite TV signals to focus the energy towards the target location.

UHF antenna

An antenna designed for the UHF frequency band, commonly used for TV signals and capable of providing a further reach for the signal.

Patch antenna

A small, circular dish antenna that attaches to the side of a building and can be used for directional connections between buildings or sites.

Spread Spectrum Wireless Transmission

A method of transmitting data over a range of frequencies using different techniques such as direct sequence spread spectrum (DSSS), frequency hopping spread spectrum (FHSS), and orthogonal frequency division multiplexing (OFDM).

Direct Sequence Spread Spectrum (DSSS)

A spread spectrum technique that modulates data over the entire range of frequencies using a series of signals called chips. It is less commonly used due to slower bandwidth and susceptibility to interference.

Frequency Hopping Spread Spectrum (FHSS)

A spread spectrum technique that allows devices to hop between predetermined frequencies, making it harder to guess the frequency. It is not commonly used in commercial wireless networks due to slower bandwidth and reduced available spectrum.

Orthogonal Frequency Division Multiplexing (OFDM)

A spread spectrum technique that uses a slow modulation rate with simultaneous transmissions over multiple data streams. It provides higher data rates and resistance to interference.

Frequencies and Channels

Wireless networks operate in specific frequency bands, such as 2.4 GHz and 5 GHz. Channels are virtual pipes that transmit information over the wireless networks. In the 2.4 GHz spectrum, there are 11 channels (or 14 channels depending on the region), while in the 5 GHz spectrum, there are 24 non-overlapping channels. Channel bonding allows for wider channels and increased data transmission but increases the risk of interference.

2.4 GHz spectrum

The frequency range commonly used by Wi-Fi devices, including wireless B, G, N, and AX networks. It is also used by other household devices such as security cameras, walkie-talkies, and baby monitors.

A, B, G, N, AC, AX

The different types of Wi-Fi networks that should be memorized for the exam. A refers to 802.11a, B refers to 802.11b, G refers to 802.11g, N refers to 802.11n, AC refers to 802.11ac, and AX refers to 802.11ax.

802.11a

Wireless A operates in the 5 GHz spectrum and has a speed of 54 megabits per second. It was primarily used by business users due to its high cost.

802.11b

Wireless B operates in the 2.4 GHz spectrum and has a speed of 11 megabits per second. It became widely adopted due to its low cost and compatibility with various devices.

802.11g

Wireless G operates in the 2.4 GHz spectrum and has a speed of 54 megabits per second. It was introduced as a replacement for wireless B to provide faster networks.

802.11n

Wireless N operates in either the 2.4 GHz or 5 GHz spectrum and has speeds ranging from 300 to 600 megabits per second. It introduced MIMO technology for faster and more efficient data transfer.

802.11ac

Wireless AC operates exclusively in the 5 GHz spectrum and can reach speeds up to three gigabits per second. It uses MU-MIMO technology for multiple users to access the network simultaneously.

802.11ax

Wireless AX, also known as Wi-Fi 6, operates in the 2.4 GHz and 5 GHz spectrum. It can reach speeds up to 9.6 gigabits per second and is fully backwards compatible with all previous Wi-Fi standards.

MU-MIMO

Multiple User, Multiple Input, Multiple Output is a technology used in 802.11ac and 802.11ax networks. It allows multiple users to access the wireless network simultaneously, improving efficiency and avoiding congestion.

Radio Frequency Interference (RFI)

Interference caused by other devices operating on similar frequencies as Wi-Fi networks. This can impact the performance and reliability of wireless networks.

2.4 GHz frequency

The frequency band commonly used by wireless networks that can be interfered with by devices operating in the same frequency range, such as microwaves.

Physical interference

Obstacles or objects, such as walls, cabinets, or appliances, that can block or weaken wireless signals, causing signal strength issues.

Attenuation

The decrease in signal strength or quality due to interference or obstacles, which can result in blocked or weakened signals.

Signal-to-noise ratio

The ratio of the desired signal (data) to background noise or interference in a wireless network, which affects the network's performance and can lead to retransmissions and slower speeds.

CSMA/CA

Carrier sense multiple access with collision avoidance, a protocol used in wireless networks to prevent collisions by listening to the frequency and sending RTS (Request To Send) and CTS (Clear To Send) packets before transmitting data.

Pre-Shared Key

A shared encryption key used in wireless networks, where both the access point and client devices have the same key to create an encrypted connection.

WEP

Wired Equivalent Privacy, an insecure wireless security protocol that uses a static Pre-Shared Key and a weak encryption algorithm, making it vulnerable to attacks.

WPA

Wi-Fi Protected Access, a wireless security protocol that replaced WEP and introduced TKIP (Temporal Key Integrity Protocol) and MIC (Message Integrity Check) to enhance security and integrity of data transmission.

WPA2

Wi-Fi Protected Access 2, the current standard for wireless security that uses stronger authentication, encryption, and integrity checks, including CCMP (Countermode with Cipher Blockchaining Message authentication code protocol) and AES (Advanced Encryption System).

AES

Advanced Encryption System, a strong encryption algorithm used in WPA2 that uses a 128-bit or higher key length to ensure confidentiality of data transmitted over a wireless network.

Password Attacks

Methods used by hackers to crack passwords, such as brute force attacks or dictionary attacks.

WPA2

A wireless security protocol that supports two modes:Personal Mode (Pre-Shared Key) and Enterprise Mode (central authentication server).

Open Network

A wireless network that has no security or password protection.

WEP

A weak wireless security protocol that uses Initialization Vectors and is vulnerable to attacks.

WPA

A wireless security protocol that uses TKIP and RC4 for encryption, considered weak and not recommended.

WPA2

A wireless security protocol that uses CCMP for integrity and AES for encryption, considered more secure than WPA.

Aircrack-ng

A popular tool used for capturing wireless packets and cracking Pre-Shared Keys.

802.1x

A network authentication protocol used for wired and wireless networks, allowing individual user authentication.

EAP

Extensible Authentication Protocol, part of 802.1x, used for network authentication with different modes like EAP-FAST, EAP-MD5, and EAP-TLS.

MAC Address Filtering

A security measure that allows or denies access to a network based on the device's MAC address.

Network Access Control (NAC)

A security mechanism that permits or denies network access based on device characteristics rather than user credentials.

Captive Portal

A webpage that requires authentication or acceptance of terms and conditions before granting access to a network.

Geofencing

Using GPS and RFID to define boundaries for devices, allowing or restricting access based on location.

Disabling SSID Broadcast

Hiding the Service Set Identifier (SSID) of a wireless network, requiring manual entry of the network name to connect.

Rogue Access Point

A maliciously set up access point that tricks users into connecting, allowing the attacker to intercept and steal data.

Rogue Access Point

A malicious access point that impersonates a legitimate network, allowing hackers to intercept and capture users' data.

Unsecured network

A network that lacks proper security measures, making it vulnerable to attacks and data interception.

War Driving

The act of driving around to identify and locate open or unsecured wireless networks.

War Chalking

The practice of marking symbols or codes on physical surfaces to indicate the presence of a wireless network, often used to share information about open networks.

MAC Filtering

A security feature that allows only specific devices with pre-approved MAC addresses to connect to a wireless network.

SSID Broadcast

The feature that allows a wireless access point to broadcast its network name, enabling devices to easily discover and connect to it.

WPA2

Wi-Fi Protected Access 2, a security protocol that provides stronger encryption and authentication for wireless networks compared to WPA or WEP.

Wireless Isolation

A feature that isolates each wireless device on a network, preventing them from communicating directly with each other.

Guest Network

A separate network within a wireless router that allows guests to connect to the internet without accessing the main network and its devices.

MAC Address

A unique identifier assigned to network interface controllers (NICs) for communication on a network.

WPS (Wi-Fi Protected Setup)

A feature in routers that allows for easy pairing and secure connection between devices by sharing a router PIN.

Remote Management

A feature that allows for remote access to a device's web-based graphical interface over the internet.

WPA2 (Wi-Fi Protected Access 2)

A wireless security protocol that provides stronger encryption and security compared to WEP.

SSID Broadcast

The act of broadcasting the network name (SSID) publicly, which can be disabled to make the wireless network harder to detect.

Wireless Isolation

A feature that isolates channels and frequencies in a wireless network, making it act more like a switch and less like a hub.

MAC Filtering

A security feature that allows or denies network access based on the MAC address of a device.

Initialization Vector Attack

A method of attacking WEP-protected access points by exploiting the weak 24-bit initialization vector used in WEP encryption.

WEP (Wired Equivalent Privacy)

An outdated and insecure wireless security protocol that should be replaced with WPA2.

Airodump-ng

A command-line tool used for capturing and analyzing wireless network packets.

Fake Authentication

A technique used to authenticate to a wireless network without using the correct credentials.

Passcode

The sequence of characters used to gain access to a device or network.

Cracked

Successfully deciphered or decoded.

IP address

A unique numerical label assigned to each device connected to a computer network.

Network

A group of interconnected devices or systems that can communicate with each other.

Join

To connect or become a part of a network or group.

Pull

To retrieve or obtain information or data.

Access point

A device that allows wireless devices to connect to a network.

BSSID

Basic Service Set Identifier, a unique identifier assigned to a wireless access point.

WirelessHacking

Refers to the act of gaining unauthorized access to a wireless network.

Hack

An unauthorized intrusion into a computer network or system.