Using the Internet: Making the Most of the Web’s Resources

Topics

Internet communications Online annoyances How the Internet works Internet Basics Origin of the Internet Future of the Internet

Communications through the Net

VOIP Wikis Newsgroups Email Mailing lists Social networking E-commerce

Voice over Internet Protocol VoIP - The Internet as a means to place phone calls Uses technology similar to e-mail to send voice data

digitally Requires

a microphone an Internet connection A VoIP provider

Services differ Free services require an account on both ends Paid services connect phone to computer Cable and DSL providers offer phone through broadband WiFi IP phones call through Internet hotspots and wireless

networks

Wikis

A wiki is a Web site that allows anyone to change its content

Wikis provide an excellent source for collaborative writing

Unlike blogs, wikis can be edited for a “common” opinion

Edits can be anonymous or named Be careful of bias in entries “wiki” is a Hawaiian word for “fast” First site with wiki in the name set up in 1995

Newsgroups

Usenet "News" formed in 1980

Online discussion forums

Post and reply to messages publicly

Need a feed from a news server - most ISPs have one

E-mail

fast, convenient, cheap

asynchronous E-mail accounts

Client-based Web-based

Forwarding(image from Wikipedia "How

Email Works")

Mailing lists

"Listservs" people must subscribe messages sent by email sent only to people who subscribe,

not general public do NOT use the "Reply All" option

unless you mean to!

Social Networking

MySpace, FaceBook easy, cheap danger of identity theft danger of revealing information

which can be harmful later danger of sexual predators

E-commerce

buying, selling, advertising, banking look for secure "signed" sites https:// versus http:// check with Better Business before

buying use credit card for purchase

Online Annoyances

Spam – electronic junk mail Pop-ups – intrusive advertising Cookies – tracking user’s browsing

habits Malware - software that has a

malicious intent - spyware, viruses, Trojans, worms, etc.

Phishing and Hoaxes – Ruses to fool and maybe steal from users

Spam Junk e-Mail May soon comprise 90%

of email volume Named after a Monty Python sketch Link Antispam practices

Don’t reply to it, even to “unsubscribe”! Use “dummy” addresses – can get free ones Read privacy statement on a site before you

give them your address Spam filters

Pop-ups

Usually advertising Pop-up

automatically Can also contain

spyware Most browsers can

prevent them Pop-up blockers

Cookies

Text files stored on client computers when visiting Web sites

Used on return visits to Web sites

Unique ID number Personal information

remembered Privacy risk

Selling information

Spyware Added as a program

piggybacked with a requested program

Secretly gathers information, usually about surfing habits

Antivirus software doesn’t detect it

Spyware removal programs are required

Spyware

Very often comes in from file-sharing, P2P sites

Ties up system resources, can modify browser settings, can spawn popups and other ads

Read the EULA for any software you install before you install!

Run Ad-Aware to clean it up

Phishing and Hoaxes

Phishing is a phony communication from a trusted source

Phishing attempts to scam someone into sending vital information

Hoaxes are attempts to scam people into sending money, or join a chain letter

Malware

Software that has a malicious intent Spyware is a form of malware Other forms are viruses, worms, and

Trojan horses Designed to render a computer

useless or control it completely

How the Internet works

Domain Names URLs Navigating the Web

Domain Names

Easy-to-remember names for Internet servers Ends with an extension that indicates its top-

level domain Every domain name corresponds to a

unique IP address Domain Name System cybersquatting

ICANN coordinates technical management of the Internet’s Domain Name System

Domain Names

Most specific information on the LEFT

Top Level Domain Names .gov .com .edu .net

Subnets and Sub Domains uky.edu cs.uky.edu www.cs.uky.edu ftp.cs.uky.edu

Current Top-Level Domains.aero Members of the air transport

industry.biz Businesses.com Can be used by anyone.coop Cooperative associations.edu Degree granting institutions.gov United States government.info Information service providers.mil United States military.museum Museums.name Individuals.net Networking organizations.org Organizations (often nonprofits).pro Credentialed professionals

Top Level Domains - Country Codes

URL

Uniform Resource Locator Unique Internet address

Protocol could be http, mailto, ftp, news, …

NOTE difference between http and https

URL http://

Protocol identifies the means of access

www.nytimes.com/

Domain name contains the host and top-level domain

Pages/cartoons/

Path identifies the subdirectories

within the Web site

Navigating the Web: Web Browsers

Software running locally on your machine

Graphical Enables Web

navigation Popular browsers:

Internet Explorer Firefox Camino (Mac OSX)

Web Sites

Web site: Collection of related Web pages First page known as Home or Index

page Web pages:

HTML documents Hyperlinks

Related pages

The Internet and Copyright

All original material on the Net is copyrighted, © or not

Copyright is violated when you get economic benefit from using the material Exception of "academic fair use"

Plagiarism is different from copyright violation – it is presenting someone else's work as your own Credit your sources!

Search Engines

“Spider” or “Web Crawler” program scans Web pages

Information found is entered in their database

User enters keyword or phrase in search box in browser

Results (hits) are sent to the client software and displayed

Evaluating Web Sites

Who is the author of the article or Web site sponsor?

What audience is the site geared toward?

Is the site biased? Is the information current? Are links available? Who is hosting? Is it a .gov

site? .edu? .com?

File-sharing - P2P networks

Files traded from machine to machine - broadband

Majority of files are copyrighted and permission has not been given for the copying

Risks Legal problems Malware in both the software and the

files

Software Copyrights and Licenses

Different types of software licenses - where the money come from? Commercial software -from sale of licenses Shareware - from registrations and ads Freeware - from advertising and spyware Open source - free labor of volunteers and

donations Public domain - donations from community

The Internet: The Basics

Protocols IP numbers Clients and servers Connecting to the Internet Origin of the Internet The Internet vs. the Web

Internet Protocols

TCP and IP serve as the primary protocols responsible for message transmission on the Internet

Internet Protocol

Messages are divided into small pieces called packets

These are labeled with the IP numbers of the machine they came from and the one they are going to, and a order number ( like 1 of 5)

The protocol says how to route them to get to the destination

Not all packets take the same route!

IP Addresses

IP addresses are addresses that identify computers on the Internet Static IP address Dynamic IP address

IP Addresses

IP addresses have the problem in TCP/IP of running out

Internet 2 consortium designing new protocols that fix the problem

Dynamic IP numbers – short term fix

Client and Server

Client computer: Users connect to the Internet Request data and Web pages

Server computers: Store Web pages and data Return the requested data to the client

Server

Client

Connecting to the Internet Dial-up connection:

Uses standard telephone line

Least costly connection

Requires a modem Converts analog

to digital and vice versa

Slowest connection speed (56Kbps)

Broadband Connections

Digital Subscriber Lines Faster than dial-up

Upload (300Kbps – 1.5Mbps) Download (1Mbps – 1.5Mbps)

Requires special DSL modem Symmetrical

or Asymmetrical

DSL modem

Broadband Connections

Cable: Uses TV coaxial

cable Fast connection

speed (500Kbps – 4Mbps)

Speed depends on number of users

Not available in all areas

Requires a cable modem

Coaxial

cable

Satellite Connections

Uses a satellite dish and coaxial cable Download speed

500 kbps Upload speed 100

kbps Signal is affected

by location and weather

Comparing Internet Connection Options

Connection Option

Maximum Upload Data Transfer Rate (approximate)

Maximum Download Data Transfer Rate (approximate)

Dial-Up 56 Kbps 56 Kbps

DSL (ADSL) 300 Kbps 1 Mbps

DSL (SDSL) 1.5 Mbps 1.5 Mbps

Cable 500 Kbps 4 Mbps

Satellite 100 Kbps 500 Kbps

Choosing an ISP

Factors to consider: Cost Local access numbers Services Offered – email, web page

hosting, news reading Reliability Speed Support and Customer Service

ISP Infrastructure

The Origin of the Internet ARPANET:

Advanced Research Projects Agency Network Funded by the U.S. government in the 1960s, lasts until 90's Allowed computers at leading universities and research

organizations to communicate with each other over great distances

First Working Version of the Packet Switching Network

NSFNet – National Science Foundation Network

Connecting 5 supercomputers and the researchers using them, 1986

commercialization of the Internet - late 80's

NSF stops funding the Net - 1994

Internet Structure

The Web

The Web is a part of the Internet distinguished by: common communication protocols TCP/IP and

HTML special links (called hyperlinks)

Web invented in 1989 by Tim Berners-Lee 1993, National Center for Supercomputing

Applications (NSF) releases the Mosaic browser

Developers of Mosaic release Netscape (1994)

The Internet vs. The Web Internet – part of the system that is primarily

hardware infrastructure (telecommunications, routers, servers, disk drives, etcetera)

Web – part of the system that contains intellectual property in many formats (text files, graphic files, sound files, video files, etc.)

The Internet existed before the WWW interface – people used command line programs

Future of the Internet

Large Scale Networking (LSN): Research and

development of cutting-edge networking and wireless technologies

Internet2: Project sponsored by

universities, government, and industry to develop new Internet technologies

Internet2 backbone supports transmission speeds of 9.6 Gbps

Internet Access Security

"always on" is security risk - turn the computer off!

keep OS and anti-virus software up to date

USE firewall software browser security settings for LAN, use NAT - router Network

Address Translation virtual private network (VPN)

Issue: Free Wi-Fi access

Some people offer wireless access for free to the community

A good point - people who can't afford to pay for it can use it

Broadband providers don't like people giving it away for free

A bad point - can be used for illegal activities