Info Tech Final

Front 1

Important changes that TV technologies have brought about.

Back 1

Time shifting, space shifting, and content shifting.

Front 2

Terminal

Back 2

where services are used

Front 3

Examples of terminals

Back 3

display terminal, desktop, and mainframe.

Front 4

Connection between the terminal and the server is via a ________________________

Back 4

communications link

Front 5

Lines and channels are usually ______?

Back 5

physical

Front 6

Links are usually ______________?

Back 6

conceptual connection

Front 7

One important consideration of the communications line is the _________?

Back 7

medium (twisted pair, microwave, satellite, etc)

Front 8

One of the major things that affects transmission speed is the ______?

Back 8

signal to noise ratio

Front 9

Three speed categories

Back 9

narrow-band, voice band, wide band

Front 10

Narrow band

Back 10

slowest band

only used for military and emergency communications

Front 11

Voice band

Back 11

speed necessary to have understandable speech

Front 12

Wide band

Back 12

most forms are now broadband (DSL, cable, etc)

Front 13

Transmission mode

Back 13

digital or analog

Front 14

Modem

Back 14

changes from digital to analog and back

Front 15

Three possibilities for transmission type

Back 15

simplex, half duplex, and full duplex

Front 16

Simplex

Back 16

data moves in only one direction

Front 17

Half duplex

Back 17

data can move in either direction, but only one direction at a time (walkie-talkie)

Front 18

Full duplex

Back 18

data can be sent both directions at the same time

Front 19

Protocol

Back 19

process that needs to be gone through to turn around the signal in the half-duplex lines

Front 20

Two types of lines

Back 20

leased line and switched line

Front 21

Leased line

Back 21

there is a specific channel for the exclusive use of one user. this line is always available

Front 22

Switched line

Back 22

there are a set of lines available. must log on to use line

Front 23

two types of connections

Back 23

point-to-point connections and multidrop connections

Front 24

Point-to-point connections

Back 24

one terminal is connected to server

Front 25

multidrop connection

Back 25

several terminals share the same line

Front 26

two common ways to identify to the server where the message came from

Back 26

polling and CSMA/CD

Front 27

One important feature of the network is how the ___________?

Back 27

connections are arranged

Front 28

Ways connections can be arranged?

Back 28

star, ring, mesh, bus

Front 29

The simplest networks are ____________

Back 29

bridges

Front 30

Network sizes

Back 30

LAN, MAN, WAN, PAN

Front 31

worm

Back 31

like a virus except requires a network

Front 32

logic bombs

Back 32

code in programs that carries out destructive actions when some criteria is met

Front 33

trap doors

Back 33

code that allows actions to be carried out that normally is not allowed

Front 34

authentication

Back 34

determining that someone is who they say they are

Front 35

authorization

Back 35

giving access to the system or parts of the system

Front 36

Three major approaches to authentication

Back 36

what you know

what you have

who you are

Front 37

databases

Back 37

interrelated self-describing set of files

Front 38

metadata

Back 38

data about data

Front 39

storage hierarchy

Back 39

field

record

file

Front 40

field

Back 40

set of contiguous bytes that store one item of information

Front 41

record

Back 41

set of related fields

Front 42

file

Back 42

set of related records

Front 43

key field

Back 43

used to put records in order or locate a specific record

Front 44

two types of key fields

Back 44

group and unique

Front 45

group key

Back 45

allows you to sort records

Front 46

unique key

Back 46

allows to locate a specific record

Front 47

database management systems (DBMS)

Back 47

a set of programs to manage the structure of the database and control access to the data

Front 48

database models

Back 48

hierarchical

network

relational

object oriented

multi-dimensional

Front 49

hierarchical database

Back 49

records organized like a family tree

Front 50

network database

Back 50

similar to hierarchical, but a record can have more than one parent

Front 51

relational database

Back 51

most common form today

data is stored in tables

Front 52

object oriented database

Back 52

data is organized into objects in the database files

Front 53

multi-dimensional database

Back 53

primarily intended for analysis of data

Front 54

two forms of magnetic disks

Back 54

floppy and hard

Front 55

hard disks are usually __________

Back 55

fixed

Front 56

advantages of hard disks

Back 56

greater storage density

faster access speed

Front 57

advantage of floppy disks

Back 57

recording medium is removable

Front 58

two types of disk organization

Back 58

sector and cylinder

Front 59

sector organization

Back 59

each surface is divided into wedge-shaped pieces called sectors

Front 60

cylinder organization

Back 60

there are a number of surfaces

cylinder is the set of all tracks on all surfaces at a particular position

Front 61

optical disks

Back 61

uses light

data is recorded as dark and light spots

Front 62

advantages of optical disks

Back 62

greater storage density

data will last longer

Front 63

disadvantages of optical disks

Back 63

most forms cannot be erased and reused

slower access speed

Front 64

two major ways to input data

Back 64

batch and interactive processing

Front 65

batch processing

Back 65

gathers data over a period of time, transcribes the data into a machine readable format, then processes the data as a group

Front 66

two major phases in batch processing

Back 66

data entry and processing

Front 67

advantages of batch processing

Back 67

economical

data entry can be done offline

Front 68

disadvantage of batch processing

Back 68

there is a time delay

Front 69

when must batch processing be used

Back 69

must be used when results depend on the group of data

Front 70

interactive processing

Back 70

data entered into the system directly and processed immediately

Front 71

advantage of interactive processing

Back 71

no time delay

Front 72

disadvantage of interactive processing

Back 72

more costly

Front 73

when must interactive processing be used

Back 73

when an immediate response is required

when the next input depends on previous outputs

Front 74

two types of equipment used in batch processing

Back 74

data entry equipment and input equipment

Front 75

equipment used in interactive processing

Back 75

keyboards, pointer devices, commercial devices

Front 76

relative pointer devices

Back 76

location is unimportant

control cursor by the way the device is moved

Front 77

absolute pointer devices

Back 77

location of the device is important

can be made to work like a relative device, but not vice versa

Front 78

examples of commercial devices

Back 78

bar code scanners, light wands, magnetic strip readers

Front 79

batch processing tends to use what kind of output equipment

Back 79

printers

Front 80

interactive processing tends to use what kind of output equipment

Back 80

monitors

Front 81

characterizing our printers

Back 81

how character is formed

how character is transferred

what unit is printed

what interface is used

Front 82

how is character formed on a printer?

Back 82

fully-formed

dot-matrix (most common)

image (rarely used today)

Front 83

how is the character transferred to the page?

Back 83

impact vs non-impact

Front 84

impact printer types

Back 84

front-striking (like a typewriter)

hammer striking (hammer presses paper against type element)

Front 85

non-impact printer

Back 85

transfers by other means

laser, ink-jet, thermal

tends to be faster than impact

Front 86

what unit is printed at one time?

Back 86

character

line

page

Front 87

what interface is used?

Back 87

serial or parellel

Front 88

serial interface

Back 88

transfers the bits of the byte one after the other

Front 89

advantage of serial interface

Back 89

less costly

Front 90

disadvantage of serial

Back 90

slower

Front 91

parallel interface

Back 91

transfers all eight bytes at one time

Front 92

advantage of parallel interface

Back 92

faster

Front 93

disadvantage of parallel interface

Back 93

more costly

Front 94

factors in selecting a printer

Back 94

purchase price

print quality

print speed

reliability

cost

flexibility

Front 95

CRT monitors most common has a __________

Back 95

glass tube like in TV sets

Front 96

what does the cathode generate in CRT monitors

Back 96

electrons

Front 97

why is in necessary to redraw the image?

Back 97

the phosphor only glows for a short period of time

Front 98

two ways of forming image

Back 98

vector graphics monitor or raster monitor

Front 99

vector graphics monitor

Back 99

draw the lines that make up the image

Front 100

advantage of vector graphics monitor

Back 100

high resolution

Front 101

disadvantage of vector graphics monitor

Back 101

as the complexity of the image increases so does the memory and the refresh rate decreases

Front 102

raster pattern

Back 102

move the beam in a constant pattern and only turn it on for dots that make up the image

Front 103

pixels

Back 103

dots that make up the image

Front 104

advantage of raster monitor

Back 104

refresh rate is constant

amount of video memory is constant

Front 105

disadvantage of raster monitor

Back 105

resolution is not as high

Front 106

why is the resolution not as high in raster monitors

Back 106

memory

Front 107

display adapters (video cards)

Back 107

circuitry that makes the monitor work

Front 108

different types of display adapters

Back 108

MDA, CGA, EGA, VGA, XGA, and sVGA

Front 109

CGA

Back 109

has color and can display graphics

allows for four colors of a possible sixteen

Front 110

advantage of CGA

Back 110

more flexible

Front 111

disadvantage of CGA

Back 111

requires more memory and computer processing power

Front 112

EGA

Back 112

more colors - 16 of a possible 64

Front 113

advantage of EGA

Back 113

images are clearer and look better because of greater range of colors

Front 114

disadvantage of EGA

Back 114

needs more memory

Front 115

VGA

Back 115

more colors

photo-realistic image

64 of 256K

Front 116

XGA

Back 116

color allowed 128 of 256K

Front 117

sVGA

Back 117

colors same as VGA, but has higher resolution

Front 118

CRT monitors are ______________

Back 118

heavy

bulky

fragile

require a lot of power

Front 119

flat panel monitors are ______________

Back 119

opposite of CRT monitors

Front 120

what is the most common form of display

Back 120

LCD

Front 121

major problem with LCD display

Back 121

it is expensive, low resolution, shallow viewing angle

Front 122

bandwidth (channel capacity)

Back 122

measure of how much data can be sent in a given amount of time

Front 123

ISP

Back 123

internet service providers

Front 124

commercial online services

Back 124

provide the internet connect and other content and services

Front 125

wireless internet service providers

Back 125

like ISP but with a wireless connection

Front 126

point of presence (POP)

Back 126

local connection provided by ISP

Front 127

network access point (NAP)

Back 127

connection for the ISP to the internet

Front 128

backbone

Back 128

set of high speed lines that connect the gateways of a network

Front 129

packets

Back 129

block of data for transmission

Front 130

IP addresses

Back 130

used to identify particular devices

Front 131

URL

Back 131

universal resource locator

Front 132

ICANN

Back 132

prevents conflicting IP addresses and URLs

Front 133

snooping

Back 133

reading personal emails

Front 134

spam

Back 134

unsolicited emails, usually advertising or chain letters

Front 135

spoofing

Back 135

faking legitimate email addresses to appear to come from a known source

Front 136

pharming

Back 136

malicious software sends you to different website even if correct URL is used