Network+ Ch 12

802.11a

Wireless networking standard that operates in the 5-GHz band with a theoretical maximum throughput of 54 Mbps.

Orthogonal Frequency Division Multiplexing

employs a digital multicarrier modulation scheme that allows for a more tightly compacted transmission -the modulated signals are perpendicular ***** and do not cause interference with each other -requires smaller freq set (channel bands) -offers greater throughput

Transmit Power Control

An IEEE 802.11a technology to reduce interference.

Near Field Communication

a protocol, based on RFID, that defines how a network uses close-range radio signals to communicate between two devices or objects equipped with ***** technology

Dynamic Frequency Selection

***** is a mandate for radio systems operating in the 5GHz band to be outfitted with means to identify and take action to avoid other radio transmissions that are considered primary-use or mission-critica

5.0 GHz

802.11a, 802.11h, 802.11n, 802.11ac

Independent Basic Service Set

A basic unit of organization in wireless networks formed by two or more wireless nodes communicating in ad hoc mode.

Service Set Identifier

A unique character string used to identify an access point on an 802.11 network.

Wireless Infrastructure

A wireless network in which devices communicate through a central access point.

Half Duplex

Communication between two devices whereby transmission takes place in only one direction at a time.

war driving

Searching for wireless signals from an automobile or on foot using a portable computing device.

Wi-Fi Protected Access

Security standard that improves on older security standards by authenticating network users and providing more advanced encryption techniques.

Multiple input-multiple output

The ability for access points to issue multiple signals to stations, thereby multiplying the signal's strength and increasing their range and data-carrying capacity. Because the signals follow multipath propagation, they must be phase-adjusted when they reach their destination.

Hotspot

Wireless access points that provide Internet access and are often available in public places such as coffee shops, libraries, bookstores, colleges, and universities.

unidirectional

one direction

Roaming

the extension of service or coverage in a wireless telecommunications system

802.11g-ht

An adaptation of 802.11g technology that allows older access points to emulate higher 802.11n-like speeds. The ***** stands for high throughput and is accomplished by improvements such as DIDO (distributed-input distributed-output), where multiple access points work together, or channel bonding.

Antenna Placement

Critical for proper coverage. Should be placed near the center of the area to be covered. Can be internal or external.

Wireless Bridge

Device used to connect two wireless network segments together, or to join wireless and wired networks together in the same way that wired bridge devices do.

MUMIMO

Multiuser Multiple Input, Multiple Output

Rouge Access Point

an unauthorized access point to a wireless network

AP placement

The location of where these go affects signal strength and network access.

Extended Service Set

A configuration of multiple BSSs used to handle mobility on a wireless network.

Heat Map

A map of Wi-Fi signals and other electromagnetic noise in a specific location.

Transport Layer Security

A security protocol that uses certificates and public key cryptography for mutual authentication and data encryption over a TCP/IP connection.

thick AP

A self-contained AP that can do its job without relying on a higher-level management device.

Bluetooth

Allows electronic devices like cell phones and computers to exchange data over short distances using radio waves

Network Interface Card

An expansion card that enables a computer to connect other computers or to a cable modem to facilitate a high-speed Internet connection.

SSID broadcast

The transmission of the SSID from the access point to wireless devices.

Basic Service Set

The wireless nodes (including the WAP) communicating together in infrastructure mode.

Temporal Key Integrity Protocol

Deprecated encryption standard that provided a new encryption key for every sent packet.

Wireless Mesh

***** networking treats each base station as a node that exchanges information continuously about network conditions with all adjacent nodes across the entire set. This allows nodes that aren't sending and receiving data to each other to still know all about each other. This knowledge might reside in a cloud-based backend or in firmware on each router.

Site Surveys

***** of the facility document AP locations but can also identify rogue APs. A rogue AP is an undocumented AP and might not be secured properly to be transmitting sensitive data.

2.4GHz

802.11b, 802.11g, 802.11n, and bluetooth Frequency

block acknowledgement

802.11n can pass many packets before an acknowledgment is required

Wireless Access Point

A central connecting device used in wireless networks.

wireless controller

A centralized appliance or software package that monitors, manages, and controls multiple wireless access points.

Small office/home office

A classification of networking equipment, usually marketed to consumers or small businesses, that focuses on low price and ease of configuration. ***** networks differ from enterprise networks, which focus on flexibility and maximum performance.

Wi-Fi Protected Access 2

A data encryption standard compliant with the IEEE802.11i standard that uses the AES protocol. ***** is currently the strongest wireless encryption standard.

VLAN pooling

A feature on wireless controllers that groups multiple VLANs into a single VLAN group, or pool, and then dynamically assigns wireless clients to each successive VLAN in the pool.

Wired Equivalent Privacy

A key encryption technique for wireless networks that uses keys both to authenticate network clients and to encrypt data in transit.

Infared

A line-of-sight wireless standard. It allows devices to transmit and receive data using LEDs and IR sensors, similarly to how TV remote controllers work.

MAC filtering

A method used to filter out which computers can access the wireless network; the WAP does this by consulting a list of MAC addresses that have been previously entered.

thin AP

A simple AP that must be configured from the wireless controller's console in order to function.

Remote Authentication Dial-In User Service

A standard method for verifying the identity of users attempting to connect via dial-in access.

Omnidirectional

A type of antenna that issues and receives wireless signals with equal strength and clarity in all directions. This type of antenna is used when many different receivers must be able to pick up the signal, or when the receiver's location is highly mobile.

Replay Attack

A type of network attack where an attacker captures network traffic and stores it for retransmission at a later time to gain unauthorized access to a network.

Direct Sequence Spread Spectrum

A type of radio transmission in which a single data signal is converted into multiple digital data signals called chips.

Tunneled Transport Layer Security

A variant of TLS that provides authentication like SSL/TLS, but does not require a certificate for each user. Instead, ***** authenticates the server end of the connection by certificate, and users are authenticated by password only or some other legacy method.

802.11n

A wireless network standard that defines speeds of up to 600 Mbps. It is downward-compatible with 802.11a, 802.11b, and 802.11g.

Lightweight Access Point Protocol

A wireless protocol created by Cisco that makes centralized wireless management possible. ***** directs all wireless frames to the wireless controller by adding extra headers to the frames, but it is also considered a lightweight protocol because the headers are relatively small.

802.11a-ht

An adaptation of 802.11a technology that allows older access points to emulate higher 802.11n-like speeds. The ***** stands for high throughput and is accomplished by improvements such as DIDO (distributed-input distributed-output), in which multiple access points work together, or channel bonding.

Advanced Encryption Standard

An encryption standard used by WPA2 and is currently the strongest encryption standard used by Wi-Fi.

Wireless Security

Any method of securing your WLAN network to prevent unauthorized network access and network data theft while ensuring that authorized users can connect to the network.

Channels

Communication pathways that travel through the air as radio frequencies or microwave signals.

WPA-Enterprise

An authentication scheme for Wi-Fi networks that combines WPA with RADIUS.

Device density

Number of devices expected to connect to the network at a particular location

802.1x

The IEEE standard that defines port-based security for wireless network access control

signal strength

refers to the strength of a connection over a wireless (radio) telecommunication system

Smart antennas

Multiple antennas and changing the phase of waves coming from different antennas an access point can focus signals toward individual hosts instead of broadcasting them.

CSMA/CA

Network method in which carrier sensing is used, but nodes attempt to avoid collisions by transmitting only when the channel is sensed to be "idle".

Yagi

Point to Point, Focus all their power in a single direction

Personal Area Network

Short range network between a computer and a mobile phone or similar portable device.

Basic Service Area

The coverage area an access point provides in a wireless network.

Request to Send/Clear to Send

The optional mechanism used by the 802.11 wireless networking protocol to reduce frame collisions introduced by the hidden node problem.

Goodput

The throughput experienced at the application level, such as the quality of a video feed or the speed of a Web page loading in the browser.

802.11b

Wireless networking standard that operates in the 2.4-GHz band with a theoretical maximum throughput of 11 Mbps.

802.11g

Wireless networking standard that operates in the 2.4-GHz band with a theoretical maximum throughput of 54 Mbps and is backward compatible with 802.11b.

802.11ac

Wireless networking standard that operates in the 5-GHz band and uses multiple in/multiple out (MIMO) and multi-user MIMO (MU-MIMO) to achieve a theoretical maximum throughput of 1 Gbps.

Wireless Local Area Network

a LAN communication technology in which radio, microwave or infrared links take the place of physical cables

spatial multiplexing

a wireless networking technology that transmits two or more streams of data in the same frequency channel

WPA Personal

aka WPA-PSK - preshared key - configure access points with start key value used to encrypt traffic