CompTIA Net+ N10-007 Chapter 14: Wireless Networking

In the United States a WAP using the 2.4-GHz band may only use channels _____ through _____.

1 through 11

In the US, WAPs on the 2.4 GHz frequency use channels _____, _____, or _____ by default because these are the only non-overlapping channels.

1, 6, 11

For the 2.4-GHz band, the 802.11 standard defines _____ channels with a bandwidth of _____ each.

14, 20 Mhz

802.3af PoE supports a maximum of _____ watts of DC power

14.4

The original 802.11 standards use either _____ GHz or _____ GHz radio frequencies.

2.4, 5

802.3at PoE+ supports a maximum of _____ watts of DC power.

25.5

The 5.0-GHz band offers many more channels than the 2.4-GHz band. In general there are around _____ different channels in the spectrum. (number)

40

Wi-Fi technologies have been around since the late 1990s, supported and standardized under the umbrella IEEE _____ standard.

802.11

What is the oldest IEEE wireless standard?

802.11-1997

The IEEE EAP standard for Ethernet networks is _____.

802.11X

To which standard(s) is 802.11ac backwards-compatible?

802.11a

What 802.11 standard came after 802.11b?

802.11a

What wireless technology or technologies uses only the 5.0 GHz frequency range?

802.11a, 802.11ac

To which standard(s) is 802.11g backwards-compatible?

802.11b

What was the first widely adopted 802.11 standard?

802.11b

Which was more widely used, 802.11a or 802.11b?

802.11b

To which standard(s) is 802.11n backwards-compatible?

802.11b/g

The first real 802.11 security standard was _____, which addressed both authentication and encryption.

802.11i

What is the IEEE standard that defined the original PoE?

802.3af

What is the IEEE standard that revised 802.3af to output as much as 25.5 watts for PoE, named PoE+?

802.3at

Which encryption algorithm is used in EAP-PSK?

AES

What does ACL stand for?

Access Control List

Why is it unlikely that no two devices in an ad hoc network will have the same IP?

Automatic Private IP Addressing (APIPA)

What does BSS stand for?

Basic Service Set

A single WAP servicing a given area is called a(n) _____. This service area can be extended by adding more access points. This is called a(n) _____. (different terms)

Basic Service Set (BSS), Extended Service Set (ESS)

What does BSSID stand for?

Basic Service Set Identifier

The _____ defines the most basic infrastructure mode network and is the same as the MAC address for the WAP.

Basic Service Set Identifier (BSSID)

802.11i replaced TKIP-RC4 with the much more robust _____, a 128-bit block cipher that's much tougher to crack.

CCMP-AES

What does CSMA/CA stand for?

Carrier Sense Multiple Access with Collision Avoidance

What does CSMA/CD stand for?

Carrier Sense Multiple Access with Collision Detection

What does CCMP-AES stand for? (Take a water break halfway through if you need to. Stay hydrated out there folks.)

Counter Mode Cipher Block Chaining Message Authentication Code Protocol Advanced Encryption Standard

Which is more prone to interference: DSSS or FHSS?

DSSS

Which uses significantly more bandwidth than the other: DSSS or FHSS?

DSSS

Is PoE Direct Current (DC), or Alternating Current (AC)?

Direct Current (DC)

_____ spread-spectrum broadcasting sends out data on different frequencies at the same time.

Direct sequence spread-spectrum (DSSS)

Currently, out of Distributed Coordination Function (DCF) and Point Coordination Function (PCF), which is the only one implemented?

Distributed Coordination Function (DCF)

What are the two methods for collision avoidance defined in 802.11?

Distributed Coordination Function (DCF), Point Coordination Function (PCF)

What do EAP-TLS and EAP-TTLS stand for? What is the difference?

EAP with Transport Layer Security: requires certificates on both the server and every client EAP Tunneled Transport Layer Security: only requires a certificate on the server side

The most popular form of authentication used in wireless networks today is _____

EAP-PSK (Pre-shared key)

What do you call a wireless network in infrastructure mode with more than one access point?

EBSS

All WAPs in an ESS require the same _____, and if the WAPs are near eachother, use separate _____.

ESSID (network name), channels

What does ESSID stand for?

Extended Service Set Identifier

What do ESS and EBSS stand for and what is the difference?

Extended Service Set, Extended Basic Service Set. They have the same meaning.

What does EAP stand for in relation to authentication?

Extensible Authentication Protocol

What are the two main components of performing a site survey before installing WAPs?

Floor plan, Site survey tool

What is the term used to describe an error resulting from a device using a different channel than the WAP when on Wi-Fi?

Frequency mismatch

_____ spread-spectrum broadcasting sends data on one frequency at a time, constantly shifting frequencies.

Frequency-hopping spread spectrum (FHSS)

Two or more wireless nodes communicating in ad hoc mode form a(n) _____.

Independent Basic Service Set (IBSS)

_____ is the loss of packets due to an overworked WAP.

Jitter

Most manufacturers use _____ to ensure interoperability when configuring multiple types of WAPs

Lightweight Access Point Protocol (LWAPP)

What is the Cisco proprietary EAP implementation?

Lightweight EAP (LEAP) OR EAP Flexible Authentication via Secure Tunneling (EAP-FAST)

Most WAPs support_____, a method that enables you to limit access to your network based on the physical addresses of wireless NICs.

MAC address filtering

What does MIMO stand for?

Multiple Input Multiple Output

What does NAS stand for in relation to RADIUS?

Network Access Server

In RADIUS operations, the client computer first contacts the WAP, which is called a _____

Network Access Server (NAS)

What type(s) of authentication are available with WPA-PSK or WPA2-PSK?

None

Which is the latest method of spread-spectrum broadcasting: DSSS, FHSS, or OFDM?

OFDM

What are the three basic types of antennas common in 802.11 networks?

Omnidirectional, unidirectional, and patch

_____ antennas are flat, plate-shaped antennas that generate a half-sphere beam. They are usually placed on walls.

Patch

What technology enables use of a WAP without directly connecting the WAP to an AC power outlet?

PoE

What is another more common name for EAP-MS-CHAPv2?

Protected EAP (PEAP)

What type of server is needed for implementing WPA2-Enterprise?

RADIUS

What type of server supports EAP-encrypted passwords in accordance with the 802.1X standard?

RADIUS server

What does RFI stand for?

Radio Frequency Interference

What does RADIUS stand for?

Remote Authentication Dial-In User Service

The _____,sometimes called a network name, is a 32-bit identification string that's inserted into the header of each frame processed by a WAP.

SSID

a WAP advertises its existence by sending out a continuous _____.

SSID broadcast

What does SSID stand for?

Service Set Identifier

The _____ is a standard name applied to the BSS or IBSS to help the connection happen.

Service Set Identifier (SSID)

What does SNR stand for in relation to radio frequency interference?

Singnal-to-noise ratio

The original 802.11 wireless Ethernet standard defined methods by which devices may communicate using _____, which broadcasts data in small, discrete chunks over the different frequencies available within a certain frequency range.

Spread-spectrum radio waves

What does TKIP stand for?

Temporal Key Integrity Protocol

WPA works by using an extra layer of security, called the _____, around the WEP encryption scheme.

Temporal Key Integrity Protocol (TKIP)

Whats the difference between a WAP and an AP?

They are the same items, AP is just a shorter term used to describe a WAP

creating a pool of VLANs for a single SSID and randomly assigning wireless clients to one of the VLANs is called _____.

VLAN pooling

_____ is a nefarious activity that involves looking for wireless networks by using omnidirectional antennas connected to laptops using wireless sniffing programs

War driving

What does WPA stand for?

Wi-Fi Protected Access

What does WPS stand for?

Wi-Fi Protected Setup

What does Wi-Fi stand for?

Wi-Fi originally stood for wireless fidelity to make it equated with high fidelity (Hi-Fi), but it doesn't really stand for anything anymore.

What does WEP stand for?

Wired Equivalent Privacy

_____, uses a 64- or 128-bit encryption algorithm to scramble data frames.

Wired Equivalent Privacy (WEP)

_____ networks use CSMA/CD, whereas _____ networks use CSMA/CA.

Wired Ethernet, Wi-Fi

What does WAP stand for?

Wireless Access Point

What does WLAN stand for?

Wireless Local Area Network

For a many WAP network, what type of device is used to configure multiple WAPs simultaneously?

Wireless controller

Is there a difference in how frames are addressed and encapsulated between 802.11 and 802.3 Ethernet frames?

Yes

Non-metallic building materials such as brick, sheetrock and wood absorb radio signals, greatly reducing or in some case eliminating a Wi-Fi signal completely. This phenomenon is called _____.

absorption

in 802.11 _____ mode, two or more devices communicate directly without any other intermediary hardware.

ad hoc

802.11 networks run in one of two modes: _____ mode, or _____ mode

ad hoc, infrastructure

_____ is the progressive loss of radio signal strength as radio waves passes through different mediums

attenuation

With CSMA/CD, each sending node detects the collision and responds by generating a random timeout period for itself, during which it doesn't try to send any more data on the network—this is called a _____.

backoff

In almost every midsized or larger wireless network, the 2.4-GHz band is filled to capacity, even with careful use of multiple channels. This is known as _____.

bandwidth saturation

Aside from the SSID, WAP broadcast traffic includes the _____, essentially a timing frame sent at regular intervals.

beacon

Many WAPs enable you to deny specific MAC addresses from logging onto the network, creating a _____.

blacklist

Many public facilities like airports employ a _____ to control access to their public Wi-Fi networks. An attempt to connect to the network opens a Web browser that insists you follow the terms of service

captive portal

Every Wi-Fi network communicates on a _____, a portion of the spectrum available.

channel

Later 802.11g manufacturers incorporated _____ into their devices, enabling the devices to use two channels for transmission.

channel bonding

Frames transmitted on the network from two different devices at the same time will corrupt each other's signals. This is called a _____.

collision

Every wireless network adapter needs two pieces of software to function with an operating system: a _____ to talk to the wireless NIC and a _____ utility.

device driver, configuration

We overwork WAPs in many different ways, but one of the most common is by attaching too many devices to a single SSID over time, what's called _____.

device saturation

The standard straight-wire antennas that provide the most omnidirectional function are called _____ antennas

dipole

What does DSSS stand for in relation to spread-spectrum broadcasting?

direct sequence spread-spectrum

The 802.11 standard defines three different spread-spectrum broadcasting methods: _____, _____, and _____.

direct sequence spread-spectrum (DSSS) frequency-hopping spread-spectrum (FHSS) orthogonal frequency-division multiplexing (OFDM).

A(n) _____ is a rogue AP that intentionally mimics an existing SSID in order to get people to connect to it instead of the proper WAP.

evil twin

What does FHSS stand for in relation to spread-spectrum broadcasting?

frequency-hopping spread-spectrum

_____ is the ratio of increase and is measured in decibels (dB)

gain

Wireless networking has a lot of overhead. The actual number of useful bits per second is called the _____ of the wireless network.

goodput

All the methods used in wireless network security—authentication, encryption, MAC address filtering—can be considered network _____techniques.

hardening

802.11 _____ mode uses a WAP that, in essence, acts as a hub for all wireless clients.

infrastructure

In CSMA/CD when detecting traffic, the waiting period is the length of the current frame plus a short, predefined silence period called a(n) ______.

interframe gap (IFG)

In wireless networking, too much signal interference can increase _____, making the network sluggish and slow to respond.

latency

Using a wireless network adapter, you can determine important things like the _____ (whether your wireless device is connected) and the _____ (a measurement of how well your wireless device is connecting to other devices).

link state, signal strength

Ad hoc mode does not use a WAP and instead uses a _____ topology.

mesh

The 802.11n specification requires all but handheld devices to use multiple antennas to implement a feature called _____, which enables the devices to make multiple simultaneous connections called streams.

multiple in/multiple out (MIMO)

If an 802.11g network only had 802.11g devices connected, the network ran in _____ mode at up to 54 Mbps, whereas when 802.11b devices connected, the network dropped down to _____ mode and all communication ran up to only 11 Mbps. (different terms)

native, mixed

In an ad hoc network, each wireless node must be configured to use the same _____.

network name (SSID)

A(n) _____ antenna radiates the signal outward from the WAP in all directions.

omnidirectional

What does OFDM stand for in relation to spread-spectrum broadcasting?

orthogonal frequency-division multiplexing

What are the two types of wireless bridges?

point-to-point, point-to-multipoint

WPS works in two popular modes: _____ method and _____ method.

push button, PIN

What does QAM stand for in relation to broadcasting methods for wireless networking?

quadruple-amplitude modulated

For a broadcasting method, the 802.11n and 802.11ac devices use a special version of OFDM called _____.

quadruple-amplitude modulated (QAM)

a wireless network uses _____ to enable devices to communicate with each other.

radio frequency (RF) waves

Metallic materials like pipes, radiators, metal doors and windows frames will reflect (or bounce) radio waves, sending them in unsuspected directions and keeping them from getting to their target device. This phenomenon is called _____.

reflection

Glass is notorious for bending radio waves as the waves pass through them. What may look like a straight line between a WAP and client suddenly may run into problems if a glass door is placed between them. This phenomenon is called _____.

refraction

As clients move through the space covered by the broadcast area of an ESS, they will change WAP connections seamlessly, a process called _____.

roaming

An unauthorized access point is known as a _____

rogue access point

A _____ will reveal any obstacles to creating the wireless network and will help determine the best possible location for your access points.

site survey

With multiple WAPs in an ESS, clients will connect to whichever WAP has the _____.

strongest signal

Any WAP that you can access directly and configure singularly via its own interface is called a _____. A WAP that can only be configured by a wireless controller is called a _____.

thick client, thin client

802.11n throughput, range (ideal conditions), spectrum, and frequency?

throughput: 100+ Mbps range: 300 ft spectrum: OFDM (QAM) frequency: both 2.4 and 5.0 GHz

802.11b throughput, range (ideal conditions), spectrum, and frequency?

throughput: 11 Mbps range: 300 ft spectrum: DSSS frequency: 2.4 GHz

802.11a throughput, range (ideal conditions), spectrum, and frequency?

throughput: 54 Mbps range: 150 ft spectrum: OFDM frequency: 5 GHz

802.11g throughput, range (ideal conditions), spectrum, and frequency?

throughput: 54 Mbps range: 300 ft spectrum: OFDM frequency: 2.4 GHz

802.11ac throughput, range (ideal conditions), spectrum, and frequency?

throughput: Up to 1 Gbps range: 300 ft spectrum: OFDM (QAM) frequency: 5.0 GHz

Many 802.11n WAPs employ _____, a multiple-antenna technology that helps get rid of dead spots.

transmit beamforming

A(n) _____ antenna focuses a radio wave into a beam of sorts.

unidirectional

A table stored in the WAP lists the MAC addresses that are permitted to participate in the wireless network, called a _____.

whitelist

A _____ is a device designed to interconnect wireless network nodes with wired networks.

wireless access point (WAP)

A _____ is any device that looks for and documents all existing wireless networks in the area.

wireless analyzer or Wi-Fi analyzer

Many companies make _____, devices that pick up your Wi-Fi signal and rebroadcast it.

wireless range extenders