HIMA 4160Fall 2009

The evolution of the Internet Internet protocols Different options for connecting to

the InternetCommon Internet applicationsCensorship and privacy issuesThe future of the Internet

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http://www.ted.com/talks/rives_controls_the_internet.html

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The largest network of networks in the world.

Uses TCP/IP protocols and packet switching .

Runs on any communications substrate.

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From Dr. Vinton Cerf, Co-Creator of TCP/IP

Internet: largest and most well-known computer network, linking millions of computers all over the world

The Internet furnishes a standard way of sending messages and information across virtually any type of computer platform and transmission media

While Internet has become a household word only during the past decade, it has actually operated in one form or another for much longer than that

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1957 USSR launched sputnik. U.S. formed the APAR (Advanced Research Projects Agency) in DoD.

1962: Paul Baran proposed the packet switching idea. 1968 - DARPA (Defense Advanced Research Projects Agency)

contracts with BBN (Bolt, Beranek & Newman) to create ARPAnet 1970 - First five nodes:

UCLA, Stanford, UC Santa Barbara U of Utah, and BBN. 1972 – First email program was created by Ray Tomlinson

1974 - TCP specification by Vint Cerf 1981 – NSF created CSNET 1983 – Domain Name System (DNS) was created 1984 – On January 1, the Internet with its 1000 hosts

converts en masse to using TCP/IP for its messaging, NSFNet was created.

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1990 – DoD disbanded the APRANET and NSFNET become the backbone. Tim Berners-Lee implemented a hypertext system.

1992 – World Wide Web released by CERN.

1993 – First web browser Mosaic for X. Later become Netscape.

1994 – Yahoo was established 1995 – NSFNet commercialized. Amazon

was launched 1998 – Google was launched. 2001 – “dot-com bubble” bursted. 2004 – the term web 2.0 was coined

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Users (people who use the Internet)

Internet service providers (ISPs) (provide access to the Internet, typically for a fee)

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Internet content providers (provide Internet content)

Application service providers (ASPs) (provide access to Web-based software applications)

Infrastructure companies (own or operating the physical structure of the Internet)

Hardware and software companies The government and other organizations

(Internet Society, ICANN, W3C, etc.)

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Myth 1: The Internet is Free Most people and businesses pay for

Internet access Free services are often in exchange

for providing contact information or viewing advertisements

Fee-based content is growing Micropayments may be implemented

in the future for Web content

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Myth 2: Someone Controls the Internet Governments can somewhat regulate

Internet use within its country but difficult to control it well

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Myth 3: The Internet and World Wide Web Are Identical Internet = physical network WWW = one resource (Web pages)

available via the Internet Other resources are available via FTP,

e-mail, Telnet, etc.

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OSI model Internet Protocols

Application DHCP, FTP , Http, SMTP, Telnet, POP, IMAP

Presentation MIME, SSL

Session DNS

Transport TCP

Network IP

Data Link Ethernet

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Ethernet Protocols at the physical level Used for LAN.

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IP Internet Protocol responsible for moving packet of data

from node to node Forwards each packet based on a four

byte destination address (IP number). This is called IPv4.

Guess what is IPv6?

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TCP Transmission control protocol Responsible for verifying the correct

delivery of data from computer to computer

Detect errors of lost data Trigger retransmission until the data is

correctly and completely retrieved

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DNS Domain Name System Associate IP with domain names Similar to phone book Layers of networks

▪ Countries▪ US

▪ mil, org, com, net, edu, gov

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MIME Multipurpose Internet Mail Extension Extend the format of email to support

▪ Content and attachment in non-text SSL

Secure sockets layer Cryptographic protocols that provide secure

communications on the Internet for such things as web browsing, email and other data transfer.

Https = http + ssl.24

DHCP Dynamic host configuration protocol Used by computers on the network to

obtain IP address and other parameters from a CHCP server.

FTP File transfer protocol Used to transfer data from one computer

to another over the internet.

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HTTP Hypertext transfer protocol Used to transfer or convey information on the

Web. Request/response protocol

Telnet TELecommunication NETwork Terminal emulation Connect the pc to server Command line based

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SMTP Simple Mail Transfer Protocol Used for email transmission across the internet.

POP Post Office Protocol (POP) Retrieve email from remote server using TCP/IP

protocol.

IMAP Internet Message Access Control Allows a local client to access email on a remote

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In TCP/IP system, a port is a special number present in the header of a data packet

Map data to particular process running on a computer FTP port 21 HTTP port 80 SMTP port 24 POP port 110 telnet port 23

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Getting set up to use the Internet typically involves three decisions Determining the type of device Selecting the type of connection desired Deciding on the Internet service

provider tOnce these determinations have

been made, your computer can be set up to access the Internet

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Possible devices include: Desktop, notebook, or tablet

PCs Internet appliances

Mobile devices

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Need to be connected to the Internet to access it

Connections can be: Dial-up (PC has to dial via a phone line

to connect) Direct (PC is continually connected to

the Internet) Direct connections are typically

broadband Home broadband use is growing

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Dial-up connections Conventional dial-up

▪ Slow, but cheap▪ Ties up phone line

ISDN▪ Faster, but pricey▪ Doesn’t tie up phone line▪ Used by businesses more than

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Direct connections T1 lines

▪ High-speed, usually used by schools and large businesses

Cable▪ Most widely used home broadband

connection DSL

▪ Broadband option for locations where it is available (must be less than 3 miles from switching station)

Satellite▪ Broadband option for rural areas

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Direct connections, cont’d Fixed wireless

▪ Broadband option where available Mobile wireless

▪ Access via mobile phone or device▪ 3G is much faster than earlier types

of mobile wireless connections Public hotspots

▪ Both free and fee-based are available

▪ Currently Wi-Fi so short range, but WiMAX may soon be available

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http://www.free-hotspot.com/http://www.speedtest.net/ http://network-tools.com/

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When selecting an ISP, consider

Services (e-mail limits and requirements, Web space, etc.)

Speed (both upstream and downstream speeds, consistency of service, etc.)

Support (free telephone support, response time, etc.)

Cost (local access number for dial-up, hardware costs, set-up fees, etc.)

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To set up your PC Install necessary hardware Install necessary software Set up your telephone dialing software (for

some conventional dial-up connections only) Select user name, access telephone number

(for dial-up connections), and a payment method

Change browser and e-mail settings as needed

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Search sites: Web sites that help you find Web pages containing the information you are seeking Typically use a search engine in

conjunction with a database containing information about Web pages to locate appropriate Web pages

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Types of online communications Discussion groups (message boards,

newsgroups, or online forums) Chat rooms: multiple users chat Instant messaging (IM): exchange of real-

time messages Videoconferencing (teleconferencing or Web

conferencing) Voice over Internet Protocol (VoIP):

Internet telephony applications involve placing telephone-to-telephone calls over the Internet—called VoIP

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Online shopping and investing Be sure all e-commerce activities are

performed via a secure Web server

Online shopping▪ Can purchase items via

manufacturers, large businesses, small businesses, etc/

▪ Usually paid via credit card, though other options may be available

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Online shopping and investing, cont’d Online auctions (eBay, etc.)

▪ Buy from individuals▪ Seller pays auction fees

Online banking (transfer funds, check balances, pay bills, etc.)

Online investing (buy and sell stocks, bonds, and other securities

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Online entertainment

Online music (Internet radio stations, online music stores, etc.)

Online TV (TV broadcast via the Internet) Online videos (often found on news sites,

popular TV show sites, etc.) Video-on-demand (VOD)

▪ Download movies and TV shows ▪ Often only viewable for a limited time▪ Available for cell phones and mobile

devices today as well

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Online entertainment, cont’d

Video-on-demand (VOD)▪ Download movies and TV shows ▪ Often only viewable for a limited time▪ Available for cell phones and mobile

devices today as well

Online gaming (both individual and multiplayer games played via the Internet)

E-books (purchased e-books and library e-books)

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Peer-to-peer file sharing: sharing resources directly between users via the Internet Napster background and issues Both legal and illegal peer-to-peer file

sharing exists today With the availability of legal ways to

obtain digital content, some experts predict that, eventually, legal alternatives will become the norm for consumers

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Online news and research News (online newspapers, magazines, news

sites, etc.) Product, corporate, and government information

(lots of information available online) Reference sites (allow you to look up ZIP codes,

phone numbers, view maps, dictionary terms, etc.)

Portals: designed to be used as a browser’s home page (Yahoo!, MSN, Bolt, etc.)

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Online education Web-based training (WBT) and distance

learning▪ Advantages: Self-paced instruction, flexible

location, up-to-date material, immediate feedback, and customized content

▪ Disadvantages: Technology requirements and problems, anonymity, and lack of face-to-face contact

Online testing (available for both objective and performance-based exams)

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Online writing Blogs (personal Web logs) Wikis (editable collaborative Web

page) E-portfolios (personal online

portfolio)

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Online broadcasting Online radio Podcasting (personal radio) YouTube (personal video

broadcasting)

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Match.comMySpaceFacebookTwitter Monster.comLinkedin.com

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Censorship Free speech vs. offensive or

indecent materials

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Internet Internet filtering: filtering: using software using software or browser or browser options to options to block access block access to particular to particular Web pages or Web pages or types of Web types of Web pagespages

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Web as a platform Harnessing collective intelligence Data is next Intel inside End of the software release cycle Lightweight programming models Software above the level of a single

device Rich user experiences

- What is Web 2.0 by Tim O’Reilly

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Web browsing privacy Cookies: small files stored on the user’s

hard drive by a Web server▪ Add functionality (such as shopping carts

and personal preferences) to Web sites▪ Can be used to track Web activity▪ Cookie information can be personally

identifiable or non-personally identifiable▪ Cookie data can be viewed or deleted▪ Cookie settings can be changed and

software can be used to manage cookies

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Web browsing privacy, cont’d Web bugs: small, usually invisible, images

on a Web page that transmits data to a Web server▪ Difficult to spot or stop▪ Software can be used to notify you when

Web bugs are being used

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Web browsing privacy, cont’d Spyware (transmits data secretly through the

user’s Internet connection) Adware (software supported by onscreen

advertising) E-mail privacy

Only encrypted e-mail can be transmitted privately

Employers and ISPs have access to the e-mail you send through those organizations

Businesses and ISPs typically archive e-mail messages

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Very high speed (home fiber optic)Mobility and portability Alternative interfaceMore interactivity

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Evolution of the Internet Important Internet ProtocolsGetting Set Up to Use the InternetBeyond Browsing and E-MailCensorship and Privacy IssuesThe Future of the Internet

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