IST 2

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There is an access point that serves eight wireless hosts. On how many channels will these devices transmit and receive during the course of an hour or two?

1

CAT 5e and CAT 6 wiring can carry Ethernet traffic 100 meters up to ________.

1 Gbps

The 5 GHz band usually supports about ________ non-overlapping 20 MHz channel(s).

12

The maximum length for the data area of a frame is how many bytes?

1500

A wireless host sends a packet to a server on the company's wired Ethernet LAN via an access point. How many frames will be involved in this one-way transmission?

2

In 802.11g, channel bandwidth usually is ________.

20 MHz

What is the maximum power for POE Plus in the standard?

25 watts

The 2.4 GHz band supports ________ possible non-overlapping 20 MHz channel(s).

3

What type of copper wiring is widely used in Ethernet?

4-pair UTP

In the 5 GHz band, how many channels can you have with 802.11ac with 80 GHz channels?

6

We use the terms Wi-Fi and ________ interchangeably in this book

802.11

Wi-Fi Standards come from the ________ Working Group.

802.11

Which of the following is the newest Wi-Fi standard discussed in the text book?

802.11ac

Which of the following only operates in the 5 GHz band?

802.11ac

The standard for roaming among access points is ________.

802.11r

The 802.11 standard for mesh networking is ________.

802.11s

The protocol standard for VLANs is

802.1q

What 802 Working Group creates Ethernet standards?

802.3

According to the textbook, which light wavelength dominates in LANs?

850 nm

A single access point and the set of hosts it serves is called a(n) ________.

BSS

Given the following information, Switch 1 Host A connected on port 15 and is on VLAN 42 Host B connected on port 10 is on VLAN 27 Trunk link connected on port 25 to Switch 2 Switch 2 Host C connected on port 3 is on VLAN 27 Host D connected on port 5 is on VLAN 27 Host E connected on port 6 is on VLAN 42 Trunk link connected on port 32 to Switch 1 Which host or hosts can Host B communicate with?

C, D

The 802.11 standard has two mechanisms for media access control. One of two mechanisms is mandatory; it is ________.

CSMA/CA+ACK

Which of the following is more efficient and faster?

CSMA/CA+ACK

What organization CREATES Ethernet standards? (Give the most specific answer.)

IEEE

Ethernet addresses were FORMERLY called ________ addresses but are now called ___________.

MAC, EUI-48

________ is a technique for preventing two wireless stations from transmitting at the same time and therefore interfering with each other.

Media access control

According to the textbook, which of the following is used most heavily in LANs for fiber transmission links?

Multimode fiber

An access point can transmit to more than one wireless client at a time with ________.

Multiuser MIMO

Wireless network standards are ________ standards.

OSI

Ethernet UTP terminates in a(n) ________ connector.

RJ-45

In ________, when a wireless host wishes to send, it first sends a message to the wireless access point asking for permission to send. When the access point sends back a response, the host sending the original message may transmit. All other hosts must wait.

RTS/CTS

To use an access point, you need to know its ________.

SSID

What happens if two nearby access points use the same channel?

They will interfere with each other.

If an uplink from switch to switch is forwarding traffic on multiple VLAN's, we call this uplink a _____.

Trunk

In LANs, ________ typically is for ________.

UTP, access lines

Select the correct wire map for the EIA/TIA 586B standard, with the connector's tab down and the contacts facing up and away from you.

White/Orange, Orange, White/Green, Blue, White/Blue, Green, White/Brown, Brown

________ have SSIDs.

Wireless access points

The other wireless device is far away in a known direction. It would be better to use ________.

a dish antenna

An Ethernet switch knows ________.

a list of unique EUI-48 addresses and their associated port number

In digital signaling there is (are) ________ state(s).

a small number of

At 10 meters, a signal has a strength of 40 mW. About how strong will it be at 20 meters?

about 10 mW

What propagation problem is especially bad in moist air?

absorptive attenuation

An extended service set (ESS) is a group of BSSs that ________.

are connected to the same distribution system and have the same SSID

Which of the following is relatively immune to small errors?

binary signaling

The Ethernet data field contains ________.

both a packet and the LLC subheader

Which UTP quality levels can send signals at 10 gigabits per second?

both category 6 and category 6A

Beamforming can allow an access point to ________.

both direct power to individual clients and send signals to two different clients at the same time

Under the standard, Ethernet switches can provide enough power over UTP for ________.

both wireless access points and voice over IP telephones

Channels with wide bandwidths are called ________ channels.

broadband

To transmit data very rapidly, you would want a ________ channel.

broadband

Which UTP quality levels are needed to send signals 100 meters at 10 gigabits per second?

category 6A

To handle multiple conversations in radio transmission, you normally use multiple ________.

channels

Using VLANs can reduce _______

congestion

In optical fiber, light travels through the ________.

core

What type of switch connects switches to other switches?

core switches

The Ethernet length field gives the length of the ________.

data field

Ethernet standards are specified at the ________ layer.

data link

Link aggregation can increase trunk speed by a factor of ________.

depends on the number of links you aggregate

The purpose of LLC subheader is to ________.

designate the type of packet in the data field

If an Ethernet receiver detects an error in an arriving frame, it ________.

drops the frame

Optical fiber cords use two strands ________.

for full-duplex transmission

Wireless radio transmission speed is usually measured in terms of ________.

frequency

Optical fiber's main advantage over UTP is ________.

greater distance span

In a ________ topology, there is only one possible path between any two hosts.

hierarchical

Switches in an Ethernet LAN are organized in a ________ topology.

hierarchical

If more users move to an access point, this decreases ________.

individual throughput

Spread spectrum transmission is used in WLANs because ________.

it is required by regulators

Ethernet becomes the dominant of LAN technology primarily because of its ________.

low cost, compared with competing technologies

Companies are moving to the 5 GHz band because there is ________ than in the 2.4 GHz band.

more bandwidth

Modal dispersion limits transmission distance in ________.

multimode fiber

The most serious problem with wireless transmission in WLANs is ________.

multipath interference

Ethernet's hierarchical topology makes it ________.

neither expensive nor reliable

A channel extends from 55 MHz to 60 MHz. Its bandwidth is ________.

none of the above

What propagation problem becomes worse as frequency increases?

none of these

A cellular telephone uses a(n) ________.

omnidirectional antenna

A local area network operates ________.

on a customer premises

Access points take ________ from wireless devices and send them on to devices on the wired LAN. They also do the converse. (CAREFUL)

packets

Ethernet standards are specified at the ________ layer.

physical

Ethernet usually has a 100 meter distance limit for ________.

physical links

UTP categories rate the ________ of UTP cabling.

quality

CSMA/CD+ACK is ________.

reliable

Using VLANs can increase _______

security

Wireless access points typically link wireless clients to ________.

servers on a wired network

Like FM radio and Broadcast TV, in WLANs 2.4 GHz and 5 GHz are ________.

service bands

What propagation problem becomes worse as there is a large and dense object between sender and receiver?

shadow zones or dead zones

Physical layer standards govern ________.

signaling

The longest transmission distances are possible with ________.

single-mode fiber

Signals in a transmission usually ________.

spread over a range of frequencies

Untwisting wire pairs no more than 1.25 cm (a half inch) at their ends reduces ________.

terminal crosstalk interference

Wireless network standards operate at ________.

the data link layer

Access points in the same ESS communicate via ________.

the distribution system

If an 802.11n client tries to use an 802.11ac access point, ________.

they will communicate using 802.11n

The frequency spectrum extends ________.

to infinity

MIMO ________.

transmits multiple signals in the same channel

In LANs, optical fiber typically is used in ________.

trunk lines

In binary signaling there is (are) ________ state(s).

two

WLANs normally use ________.

unlicensed bands

Which of the following can increase reliability considerably in an Ethernet LAN?

using the Rapid Spanning Tree Protocol

What type of switch connects users to the network

workgroup switches

In unlicensed bands, ________.

you can use radios wherever you please


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