world’s largest public computer network, a network of networks that provides a vast array of services to individuals, businesses, and organizations around the world
internet hosts
servers that provide information and services to Internet users
the cloud
an expression that refers to Internet servers
birth of the web shift internet focus
from supporting academic and government interests to supporting public and commercial interests
ethic concerns with internet
freedom of speech, privacy and intellectual property rights
stop online piracy act- failed because gov favor internet user privacy over internet service provider snooping
government agencies working to limit
google’s data collection
internet technologies
work together to provide information and services over the Internet, including a variety of protocols, hardware and software
joining networks together into larger networks so that users on different networks can communicate
depending on the service and service provider internet connection might be:
blazing, fast, slow, filtered or unfiltered, limited or unlimited
Ex of hardware that transfers packets of data that travel over the internet (e.g.- email, photos, videos, etc)
cables, satellites, and routers
computer network
a collection of computing devices connected together to share resources such as files, software, processors, storage, and printers
internet dates back to about
1957- computing done on
large mainframe computers accessed from within an organization through a network of terminal s
sputnik in USSR led U.S to …
Dep. of Defense to advance space technologies, weapons and communication systems, ARPA and NASA , created internet
ARPA commissioned ARPANET
research into networking
initial goal= establish closer communications for research by connecting the computer networks of four research institutions UCLA, Stanford, USSB, UU, nearly 1 billion hosts today vs 13 hosts in 1970
world wide web
in early 90s, provide a graphical interface to the internet that launched the digital information revolution
Web 1.0
one way was the one-way web with information traveling in one direction from servers to consumers
web 2.0
two-way- inspired by the growing popularity of blogs
social networking trend
high quality applications ex
adobe flex, ajax, microsoft silverlight
rich internet apps ex
google docs, hulu
internet backbone
refers to the main internet pathways and connections, made up of the many national and international communication networks that are owned by the major telecom companies such as verizon, at&t and sprint (the same companies and networks that provide telephone services)
-consists mostly of fiber-optic cables
network service providers (NSPs)
large telecom companies that connect their networks so that users on all the networks could share information over the Internet
points of presence (POPs)
utility station used by NSPs to enable internet users to connect to their networks
connected by internet backbone
protocols on which the internet is based are the transmission control protocol (TCP) and internet protocol (IP)
-defining component of internet
-allows many different types of networks and devices to join together in an immense global network
-defines how information travels across the internet
data packet
how data travels across internet
a small coup of bytes that includes the data being sent and a header containing information about the data such as an email message, into small packets to make efficient use of the network
-when delivered packets= reconstructed
defines the format and addressing scheme used for the packets
– required that all devices connected the internet have a unique IP address
use use the information in the packet header to direct the packet to its destination
enables two hosts to establish a connection and exchange streams of data
-guarantees delivery of data and also guarantees that packets are delivered in the same order in which they were sent
IP address
a unique 32 bit identifier for internet isers and hosts
-read as decimal numbers
-4 numbers 0-255 separated by .
-static (permanently assigned to a computer) or dynamic (assigned to computers as needed)
current 32-bit IP address system
(IPv4) 2^32, support about 4.3 billion addresses
-addressed will soon be in short supply
internet assigned numbers authority- process of moving to internet hosts to a new IP version
internet service provider (ISP)
a company that provided individuals and organizations with access to the internet
provide connections to ISP services using an Ethernet cable
notebook computers
can access the internet using a connect card and a data plan from a cell phone service provider
largest ISP
Comcast Cable- boradband caves running through many phones
DSL (digital subscriber line)
-always on connection that uses the customer’s phone line, but there is no dialing up and users can use the internet and talk on the phone simultaneously
BPL (broadband overpower line)
utilizes existing power lines to carry internet signals
-have to plug in BPL modem
DSS < > or = to DSL
cable modem
always on connection that uses a cable tv connection to provide high-speed internet service
cellular data connection
many cell phone companies offers internet access oner their networks at speeds up to 12 Mbps
DSS (digital satellite service)
wireless high-speed internet service that utilizes a satellite and satellite dishes, provided by companies such as earthlink, hughsnet
dial up
low-speed internet service that utilizes the customers existing phone line for internet access
network architecture in which one computer or program (the client) makes a service request from another computer or program (the server), which provides the service
web browser= 1 which requests web page from 2
1 internet explorer is a client
2 web server- ex. www. monster .com
server computers
typically powerful computers that can accommodate many simultaneous user requests
-run 24/7
peer-to-peer (P2P)
a network architecture that does not utilize a central server but facilitates communication directly between clients with computers acting as both client and server
-make a portion of their file system available to other participants to access directly
P2P personal computer
PC acts as both server (as other users access files) and client (at the user accesses others files)
-ex- Gnutella file-sharing system
a type of P2P protocol that speeds up the download process by dividing files into small units and downloading multiple file unties simultaneously form different sources
allows devices to connect directly to each other to share files and services
a network device that manages network traffic by evaluating messages and routing them over the fastest path to their destination
packet-switched network
data that travels over the internet is broken into small data packets to traverse the internet more efficiently
router typically located where
one network is going to another network
DNS (Domaine name system)
maintains a database of all domain names and Ip addresses used on the internet and acts like a phonebook, supplying information to internet nodes and router s working to get data packets to their destination
internet corporation for assigned names and number manage domain names and number
internet uses DNS to
translate domain names into IP addresses
-database of names and addresses stored on DNS
____ root DNS servers make up foundation of DNS
IF DNS fails/corrupts
all internet traffic would be affected , constantly under attack, if some servers fail others take up the load
hacking technique of DNS that replaces IP addresses in the DS with the IP address of fraudulent web sites designed to spread malware
in a computer network context, a port is an address used by clients and servers that is associated with a specific service
-client/server software with the assistance of telecommunications software use port number to determine which service the data packet is requesting
port numbers
-can be used to track activity on the internet
-can be used by hackers to gain access to computer systems
-help servers organize the data packets that they manage, sending packets to correct software for service
ex- server receives web page request on port 80 and dns requests on port 53
client application includes correct port number in the outgoing packet headers
computer trick for hackers
scanning the internet for computers that have open ports- back door into a computer system
good antivirus software will make sure that all ports on all computers are closed except for those being used by a service
voice over internet protocol/ voice over IP/ VoIP
refers to technologies that support voice communications using the Internet Protocol over data networks
-supported by many businesses and smart phones
-ex- xfinity package form comcast
unified communications
when a system combines voice, video, and data communications into one interface
-can boost productivity
internet 2
a research and development consortium led by more than 200 U.S universities and supported by partnerships with industry and government to develop and deploy advanced network applications and technologies for tomorrow’s internet
-group focused on developing new ways to improve the management and performance of the existing internet
internet3 aka national lambdarail (NLR)
cross-country, high speed networking applications in science, engineering, and medicine
gemini observatories
twin 8. 1meter astronomical telescopes- used through internet2
shared virtual reality
provides immersive virtual environments over a network to be shared by participants in different locales
web technologies
the hardware, software, and protocols that allow the web to exist.
the web
aka world wide web is an internet service that provides convenient access to information and services through hyperlinks
-developed by Tim berners-lee in his CERN research in geneva- started as personal organizational tool
process of linking together documents from diverse sources
1. defined system for linking the documents
2. protocols that allow different computers to communicate
3. tools to help create the documents and the links between them
all three links
hyperlinks for docs
hypertext transfer protocol (HTTP) for comm.
HTML for creating and linking
an element in an electronic doc that when clicked opens a related document
controls communication between web clients and servers
web browser
aka browser aka web client (ex- firefox, safari) is used to request web page from web servers, interpret the HTML code in the web page that is delivered, and display it onscreen
-combined with plug ins and ajax allow you to view everything and interact with software
-sends request to web server
-in future may serve as primary user interface
web server
refers to software that fulfills web page requests from web clients and the computers that run such software
open computer project
server design available for other companies to use through an open source program
___ doesn’t define a web server but rather the ____
web hosting company/ web host
company that provides web server services to individuals and businesses interested in maintaining an online presence
-offere FTF, SFTP, SSL, email services, devewlopmental platforms, etc.
most popular web server software
Uniform Resource Locator (URL)
acts as a web page address, incorporating the domain name of the web server and the location of the web page file on the server
http: //= 1
google= 3
1 protocol
2 web server
3 domain name
4 location on server
5 requested file
top-level domain (TDL)
final portion of the domain name, ex- .com, .edu, etc
classify internate locations by type or by location
commercial business
commercial business
educational institution
nonprofit organization
networking service
government agency
personal web site
HTML (hypertext markup language)
the primary markup language used to specify the formatting of a web page
markup language
used to describe how information is to be displayed
now people use ____ instead of typing html tags
software tools that automate much of the production of HTML code
-ex- adobe dreamweaver, word press, etc
today web pages use a combo of
-web programming languages
-database technologies
HTML to ____to ____
XHTML to HTML 5…require less plug ins
XML (extensible markup language)
provides a method for describing and classifying internet-delivered data so that it is easier to organize and manage
-publishers can use XML to separate data from web page formatting
xml web content implemented using several files:
1. defines structure of data
2. provides the actual data
3. defines the format of the data presentation (HTML)
semantic web
an extension of the current web that seeks to provide a common framework to support easier and faster access to information
-combine and integrate information from many sources and application
cascading style sheet (CSS)
allows easy application of visual styles for fonts, colors, layout, and other page attributes to create a visual theme for web pages and sites
-allows style for pages to be stored on site link .css files
-customization of specific HTML tags
web development software
allows developers to create web pages more easily using a word-processing-style environment and automating complex coding activities
-more manageable and accessible
WYSIWYG (pronounced “wizzie-wig”) implies that…
the Web page you design with the Web development software will look the same when published on the Web.
aka http cookie is a small text file placed on a users computer by a web server in order to identify the user whenever he or she returns to visit a website
-behavioral targeting
-create customer profiles
HTTP= stateless protocol
the facts that a web server does not retain information (a particular state) regarding a client, or user, between visits
-treats every request as a new transaction
cookies can threaten security and privacy
most companies- track within one website
but advertiser use “third party” cookies because they are not placed on a computer by the company that owns the site
-can delete cookie files
aka extension aka add-on works with a web browser to offer extended services such as audio players, video, animation, 3D graphics viewers, and interactive media
content streaming
the media begins playing while the file is being delivered
flash player (adobe), most popular plug in
allows flash movies to play in the browser window
microsoft silverlight
similar to flash in purpose, supports media and interactive content
acrobat reader (adobe)
supports adobe pdf docs in he browser window
java runtime environment (oracle)
enables the browser to run programs written with the java programming language
quicktime (apple)
supports viewing and interacting with video, audio, and 3d created with quicktime
realplayer (realnetworks)
plays streaming real audio and real video
windows media player (Microsoft)
plays streaming audio, video, animations, and multimedia presentation in the web browser
web programming
the development of software written to run either in a web browser or on a web server, using web-based input and output
object-oriented programming language that enables software engineers to create programs that run on any computer platform
java script
similar to java in that it provides functionality on web pages through programming code that is embed in an HTML, but language was developed specifically for the web
client side programs
program codes that run in the browser after being delivered by the server
server side programs
(PHP, PER, C++) used to develop software that runs on a web server using the web browser as a user interface
Really simple syndication (RSS)
a web technology used to automatically deliver frequently updated web content, such as blogs, podcasts, and news, in a standardized fashion
-marked by a small orange rectangular icon showing XML or RSS
podcast aggregator software
aka podcast manager uses RSS to allow you to subscribe to your favorite podcasts from one central application
cloud computing
delivers a variety of computing resources from the Internet as a service for free or for a fee, to relieve users from the burden of installing, maintaing, and securing those resources themselves
-no installation, maintenance, or security played in an important role in developing the cloud
-price=benefit for businesses
drawbacks to cloud computing
-only accessible when the user is connected to the internet
-lack of control over the data- not accurately secured
cloud services
include computing services provided over the internet in three categories:
infrastructure, platform, and software
-cloud computing- software as a service
-platform as service-procides access to an operating system desktop running in a virtual machine on a server
-Infrastructure as a service provides hardware resources to users over the internet, encrypts and secures data over firewall
google play
online storage system for media and music
cloud models
serve various environments including private clouds, community clouds, public clouds, and hybrid clouds
private clouds
-service available to general public
private cloud
-created on-premises or hosted by a service provider
-provided for only one company
community cloud
several businesses or organizations
web resources
many and varied, assisting individuals, businesses, and organizations with all facets of life including education, news and information sharing, communication, travel, commerce, employment, and entertainment
search engine
a valuable software tool that enables users to find information on the Web by specifying words that are key to their topics of interest- keywords
-largest search engine
-36 billion annual revenue
-78% global market
automated programs called spiders that follow all web links in an attempt to catalog every web page by topic, stored into database
human powered search
provides search results created by human researchers
-more accurate than search engines
meta search engine
allows you to run keyboard searches on several search engines at once (ex- dog pile returns results from google and other search engines)
a web page that combines useful information and links, and acts as an entry point to the Web – the first page you open when you begin browsing the web
typical web portal includes:
search engine, a subject directory, daily headlines, and other items of interest
horizontal portals
portals cover a wide range of topics
small applications that deliver information and services
vertical portals
pages that provide information and links for special interest groups
corporate portals
aka dashboards provide access to work-related resources such as corporate news and information, along with access to business system tools and databases and communication tools to support collaboration
internet communications
text based communications such as email and instant messaging, voice communications such as voice over IP (VOIP) , video communications, and a variety of group and community forums.
pervasive communication
the ability to communicate with anyone through a variety of formats from anywhere at any time
2 forms of communication: synchronous and asynchronous
1= people communicate in real time, exchange thoughts in a fluid conversation
2= allows participants to leave messages for each other to be read, heard, or watched and to respond to messages at their convenience
communication through high-quality video and audio connections over the internet along with large hd displays to supports meetings (synch.)
online information
information of all kinds- business, personal, government, factual, opinionated, even inaccurate- that is delivered over the internet and web
types of web information
-traditional published works: many publishers and libraries are creating digital forms of past and current published works
-business- info on products, services, etc
-financial- banks and other financial institutions
-opinion- blogs
-personal- social media
-support- help with life issues
online news
newspapers, mags, journals, news, radio, tv, blogs that deliver news and information about current events on the WEB
-text and photos supported by HTML
-video/audio provided in web browser through plug ins and podcasts
-leading new agencies- reuters the assoc press the box
social/citizen journalism
ordinary citizens are more involved in reporting the news than ever before
financial services
support money management, loans, investments, and transactions for individuals, businesses, and organizations
business transactions carried out online
online education
web sites designed to educate or support education and training
distance education
conducting classes over the web with no physical class meetings
open couse ware
MIT offers free online courses- can’t earn credit though
Massively Open Online Courses
or MOOCs
online travel
web sites ans services that support various travel activities, such as preparing for travel, finding your way around new environments, reserving flights and lodging, booking tours and activities, and renting vehicles
priceline- 1
1 name your own price
2 pool a bunch of information from various sites
3 organize all travel plans
Maps and geolocation
provide geographic services for finding your way around, finding people and places, or finding information related to specific locations
-pose threat to security
google latitude tool
lets you see where your friends are
geographic information system (GIS)
provide geographic information layered over a map
technology that allows for tagging information with an associated location
augmented reality
using your phones camera, gps information, compass information, local business information, and sometimes a form of artificial intelligence call pattern recognition, application like google goggles and layer are able to overlay local information about nearby businesses and point of interest
online employment support
refers to web-delivered information and services that support researching employment options and finding employment
career hunt process.
1 select career
2 discover players
3 companies that interest you
4 view job listings at general employment websites
5view job listings at general employment web sites
6 view job listings at industry-specific employment
7 create impressive website to represent self
online music
music delivered through internet based or web-based services and includes internet radio, music subscription services, and music download services
internet radio
digitally delivered to your computer over the internet, lot more choices of stations
digital rights management (DRM)
technology that prevents or limits the users ability to make copies and play the music on multiple players
online tv and video
refers to television programming, motion pictures, movies, and user-generated video available on the web
online games
include the many different types of single-user, multiuser, and massively multiuser games played on the internet and the Web
multiplayer online role playing games types:
-flight simulation
-multiuser dimension or multiuser dungeon (MUD)
-role playing games
social media
online services that support social interaction and publishing
-ex: blogs, wikis
social networking
users to share information about themselves and to find, meet, and converse with other members
employs the power of online communities to accomplish some task
ex- twitter
allows members to report on what they are doing and thinking about throughout the day
media sharing
provide methods for members to store and share digital media files
folksonomy/ collaborative tagging
allows users to associate descriptive tags with photos
creates a tag cloud- a diagram of keyword links with the size of each word representing the amount of photos that use that tag
social bookmarking
a way for users to store, classify, share, and search web bookmarks, add ons on tool bar