Computer Science Analysis
Unlock all answers in this set
Unlock answersquestion
The internet began when and why
answer
1969, US department of defense, was originally text only. 1990's media became available
question
To connect to the internet, you need:
answer
an access device (computer with a modem), means of connection (phone line, internet hook up, etc), and and internet service provider
question
Bandwidth
answer
Expressed how much data can be sent through a communications channel in a given amount of time
question
Baseband
answer
Slow type of signal that only allows for one signal to be transmitted at a time
question
Broadband
answer
high-speed connections
question
upload
answer
downloading information from local to remote computer
question
downloading
answer
downloading data from remote to local computer
question
narrowband
answer
low speed but inexpensive modem, ie. phone lines or dial up
question
telephone modems
answer
can be either internal or external
question
DSL line
answer
expensive, is always on, high speed, less than 4.5 miles from phone company to work
question
T1 line
answer
very expensive, generally used by large organizations.
question
cable modem
answer
TV cable system with internet connection, company usually supplies a cable modem, is always on, 100 mbps
question
Satellite Dish
answer
transmits data between satellite dish and satellite orbiting the earth, connection is always on,
question
Wi-Fi
answer
wireless fidelity, transmits data wirelessly for up to 54 mbps
question
ISP
answer
internet service provider, local regional or national organization that provides access to the internet for free
question
Wireless Internet Service Provider
answer
WISP, Sprint, AT&T, verison, etc. enables wireless-equipped laptops and tablets and smartphone users to access internet
question
Internet
answer
One huge network that connects a lot of smaller networks
question
client`
answer
Computer requesting data or services
question
server
answer
/Host computer is the central computer that gives out information upon request
question
Point of Presence (POP)
answer
a collection of modems and other equipment in a local area, local gateway access to ISP network
question
Internet exchange point
answer
a routing computer at the point on the internet where several connections come together, run by private companies, allows different ISP's to change internet traffic
question
Internet Backbone
answer
high-speed and high-capacity data transmission lines usually fiber optic, uses the newest technology (sprint, AT&T verison etc.)
question
Internet 2
answer
cooperative University/business education and research project, takes old lines and adds new "toll lanes" to internet to speed things up
question
Handshaking and Authentication
answer
connecting to your ISP's POP, handshaking: fastest speed of transmission established, authentication: User ID and password
question
Protocols
answer
the set of rules a computer follows to electronically transmit data
question
packets
answer
fixed length blocks of data transmission; transmissions are broken up into packets and reassembled at destination
question
IP Address
answer
Internet Protocol address: unique address that connects devices to the internet
question
Dynamic IP VS Static IP
answer
Address changes each time with use, versus not changing at all
question
Web versus internet
answer
web is multimedia based and the internet is what supports the web
question
web sites unique address consists of:
answer
protocol (https://), domain name (barnsandnoble.com), directory name/file path (/sellback), file name and extension (home.htm)
question
Web portal
answer
yahoo, google, bing, ie a gateway website
question
individual search engines
answer
compile their own searchable data bases on the web
question
subject directories
answer
allow you to search information by selecting a list of categories or topics
question
Meta search engines
answer
allows you to search several site engines at once
question
Specialized search engines
answer
helps locate specialized subject matter such as info on movies or health or jobs (think WebMD)
question
wiki
answer
a piece of software that can be downloaded and used to make a website for free that can be corrected or added to by anyone
question
tags
answer
Do-it-yourself labels that people can put on anything found on the Internet, from articles to photos to videos, that help them to find their favorite sites again and to link them
question
Digital
answer
Computers; communicating with 1 and 0s
question
Analog
answer
humans operate in an analog, uses wave variation. sound light and temperature are analog
question
Modems
answer
they convert analog data into digital data that computers can then use
question
Wide area network
answer
WAN; communications network that covers a large geographical area (long distance phone calls)
question
Metropolitan Area Network
answer
MAN; used to communicate in a city or suburb (cellphone users)
question
Local Area network
answer
LAN; connects computers or devices to one another in a close range of each other (ie one office space or building). The organization that has the LAN owns it. (home area network)
question
clients
answer
request data
question
Servers
answer
supply data
question
Peer to peer
answer
all computers on the network are equal and communicate directly with one another with out needing a server
question
intranets
answer
functions as internet but for one company to use and access internally
question
Extranets
answer
similar to intranets but used by external sources (such as suppliers)
question
VPN virtual private network
answer
use a public network (usually the Internet) plus intranets and extranets to connect an organization's various sites) but on a private basis, via encryption and authentication
question
node
answer
any device attached to the network
question
star
answer
all nodes are connected through a central network switch
question
ring
answer
all nodes are connected into a continuous loop
question
Bus
answer
All nodes are connected to a single wire or cable
question
Tree
answer
A bus or network of star networks
question
Mesh
answer
message sent to the destination can take any shorted, easiest route to teach its destination
question
Twisted-pair wire
answer
used for dial up connections; two strands of insulated copper wire twisted around eachother (slow
question
coaxial cable
answer
insulated copper wire wrapped in a metal shield, used for cable TV and cable internet services
question
fiber-optic cable
answer
transmits pulses of light, not electricity, lower error rate, more expensive, more durable, very fast
question
Electromagnetic Spectrum
answer
radiation is the basis of all telecommunications signals, wired and wireless
question
Radio Frequency spectrum
answer
part of the electromagnetic spectrum that carries most communications signals
question
Narrow Band
answer
used for regular telephone communication
question
Satellite Heights
answer
Geo- earth orbit Meo- medium earth orbit Leo - low earth orbit
question
viruses
answer
program that hides in a file program or disk that cause unexpected effects
question
worms
answer
program that repeatedly copies itself onto the computer
question
trojan horses
answer
bad programs that disguise themselves to be useful to infultrate computer information
question
rootkit
answer
allows access to personal information, such as the study of keystrokes
question
Zombies and Bots
answer
gives access to remotely control computer
question
point and shoot camera
answer
automatically adjusts settings for you
question
single lens camera
answer
uses a reflecting mirror to reflect incomping light into crisper photos
