Internet and ImpactCS4HS at Marquette University

Internet

What is the Internet? The network of hardware and software systems that

connects many of the world’s computers Typically, people say the Internet and capitalize the “I”

because there is only one Until we meet aliens Or decide to break off from the rest of the world

The World Wide Web is the part of the Internet that is concerned with webpages

The Internet also includes: FTP VOIP Bittorrent Multiplayer video games Much, much more…

Packet switched

The Internet is a packet switched system

Individual pieces of data (called packets) are sent on the network Each packet knows where it is going A collection of packets going from point

A to point B might not all travel the same route

C

BA

D

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Circuit switched

Traditionally, phone lines have been circuit switched

A specific circuit is set up for a specific communication

Operators used to do this by hand Now it is done automatically Only one path for data

C BA1

Circuit vs. packet switching Which one is faster?

Circuit switching Which one is more

predictable? Circuit switching

So, why is the Internet packet switched? More adaptable

Birth of the Internet The Advanced Research

Projects Agency was created in 1958 to respond to the Russians launching Sputnik

The ARPANET connected its first two major nodes over 10 years later

Packet switching was used so that the network could still communicate after a nuclear strike

What the Internet isn't

A big truck A series of tubes Invented by Al Gore

He never claimed it was But he did create the

High Performance Computing Act of 1991 which funded many efforts that brought the Internet to the masses faster

IP addresses

Computers on the Internet have addresses, not names

Google.com is actually [74.125.67.100]

Google.com is called a domain The Domain Name System or DNS

turns the name into an address

IPv4

Old-style IP addresses are in this form: 74.125.67.100

4 numbers between 0 and 255, separated by dots

That’s a total of 2564 = 4,294,967,296 addresses

But there are 7 billion people on earth…

IPv6 IPv6 are the new IP addresses that are

beginning to be used by modern hardware 8 groups of 4 hexadecimal digits each 2001:0db8:85a3:0000:0000:8a2e:0370:7334 1 hexadecimal digit has 16 possibilities How many different addresses is this? 1632 = 2128 ≈ 3.4×1038 is enough to have 500

trillion addresses for every cell of every person’s body on Earth

Will it be enough?!

Other failures in design

Y2K bug 2 bytes for the date is not enough It’s all just going to get messed up in

Y10K Y2038 bug

Unix and Linux machines often use a signed 32-bit integer to represent seconds since January 1, 1970

Zip codes Vehicle identification numbers

Activity

Write down the most important aspect of your day-to-day life that had not been invented 20 years ago

Be specific! Answers like "the Internet" are too vague

My Trip to NYC

Trip to NYC

It's impossible to make a meaningful list of all the CS innovations that have impact now

Let's go on a journey to New York City that I just took with my parents

On the way, I'll try to note all the CS impacts that we come across

Air travel My parents wanted to come visit me in

Philadelphia for my birthday They live in Indiana They searched on Orbitz.com for the best

flight and then booked it through USAirways.com

How did anyone do this before the Internet? According to a 2011 Forbes article, the travel

agent business has shrunk by 14% (12,500 jobs) in the last 5 years

Bus travel From Philadelphia, we took

Megabus to NYC Booked tickets online Printed them out Waved incomprehensible

printouts at the bus driver $14 round trip per person It is possible to book tickets

on the phone, but almost all their business is online

They don't have offices or even proper bus stops But their buses have free

wireless!

Where did we stay?

We wanted to stay in Brooklyn We used AirBnB.com

People rent out their homes to travelers It's cheaper than a hotel You get full kitchen facilities

We paid $135 a night for three people

It's a level up from CouchSurfing.org

What did we eat? My parents are vegan Finding vegan food is hard

Even in NYC I used Yelp.com to find highly

rated vegan and vegetarian restaurants within walking distance

Sometimes we used AllMenus.com to make sure a non-vegetarian place had options

How did we get around?

We didn't take a single cab We walked everywhere and took the

subway I navigated with the GPS in my

iPhone 3GS We didn't make any wrong turns

Who made this possible?

Web developers at Orbitz.com, USAirways.com, Yelp.com, AirBnB.com, and AllMenus.com

Software developers at Google and Apple

Hardware developers at Apple (and the countless firms they contract with)

Network architects and technicians at AT&T

US government who putting GPS satellites in space

Other Changes

Office productivity software In 1971 a third of all working women in

the US were secretaries Now most people type their own e-mail

and printed correspondence A recent Huffington Post article

suggests that spell checking software is ruining our spelling

Few complain about spreadsheets because it's so hard to do the same work by hand

PowerPoint has made us a nation of boring presenters

Digital divide A recent NY Times article says that

the digital divide has changed Children whose parents do not have

a college degree spend 11.5 hours a day consuming media A 4:40 increase since 1999!

Children with more educated parents spend 10 hours a day consuming media

Although computer use has increased in underprivileged segments of the population, the increase has almost all been entertainment, not education

Wikipedia A 2005 Nature article suggested that Wikipedia

is more accurate than Encyclopedia Britannica But student research suffers as they no longer

learn how to track down obscure references Wikipedia has taken criticism for bias in

coverage and tone Male gender bias US cultural bias Liberal political bias

Its open model allows for anyone to vandalize Staff generally reacts quickly to errors and

defacement

Arab Spring Starting in December 2010, a

movement in the Middle East has ousted rulers of Egypt, Libya, Tunisia, and Yemen

There have been massive protests throughout the region, and tensions are still high in Syria

WikiLeaks exposed corruption and human rights abuses

The Arab Social Media Report by the Dubai School of Government confirms that many activities were organized through Facebook and Twitter

Texting

In 2009, one study showed that 286 million Americans (the vast majority of the population) sent 152.7 billion texts per month, averaging 534 each

In 2007, 700 billion texts were sent in China Half of them were spam The government monitors texts in China

Europe texts heavily as well Most plans have unlimited free texting

Finland is famous for its less-interactive society Finns have a stronger bias to talking on the

phone and texting over real-life interactions Interactive TV shows where you text to play

are popular The Prime Minister of Finland allegedly broke

up with his girlfriend over text in 2006

Impacts of texting Texting allows unprecedented

levels of communication A 2009 study showed that young

adults who used “textisms” (lol, brb) in daily writing were worse formal writers But better informal ones!

Texting reduces focus on life around us A 2008 head on train collision that

killed 25 people was likely due to an engineer texting

A 2009 VA Tech study suggests that texting while driving can increase chances of a crash by a factor of 23

Facebook Facebook is 8 and a half years old 900 million users, almost 13% of the world’s

population 50% of users log on every day The average user has 130 friends

Even with a disappointing IPO, its market capitalization is $61.5 billion

It has become a central part of how many people communicate in the developed world

What are its pros and cons?

Privacy Facebook can drastically reduce privacy

A study from CareerBuilder.com suggests that 37% of hiring managers search social media

Credit card numbers Are stolen over the Internet (though

cryptography has helped a lot) 45.6 million credit card numbers were stolen

from TJ Maxx Can be stolen using RFID readers without any

interaction from you Identity theft is on the rise

 At least 641,052 taxpayers were affected by identity theft in 2011, more than twice 2010