INFSCI 00102015 Summer Term

LEC4.ppt

Becoming Skilled at Information Technology

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IS 0010 - Summer 2015

Tentative Schedule Week of

(Monday)

1 11-May x2 18-May x3 25-May Memorial Day (no classes)4 1-Jun x5 8-Jun x6 15-Jun7 22-Jun8 29-Jun9 6-Jul Exam (date to be announced)

10 13-Jul11 20-Jul Presentations (date to be announced)12 27-Jul Final work due

Current assignment summary

• Bring an INFSCI article to each class– Due: each class … (ref LEC1)

• Start reading the text– Due: before the exam … (ref LEC1)

• Watch “Code Wars” video– http://www.intellectualtakeout.org/library/video-podcast-media/video-code-wars-america%E2%80%99s-

cyber-threat– Due: before the exam … (ref LEC1)

• Exam questions assignment– Due: one week before the exam … (ref LEC2)

• Extra articles– Net Neutrality due: 6/1/15 … (ref LEC2)– Patriot Act due: 6/8/15 … (ref LEC3)

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New Code Wars link

• Watch “Code Wars” video– http://www.intellectualtakeout.org/library/video-podcast-media/video-code-wars-america%E2%80%99s-

cyber-threat

• Note: The link to Code Wars that is in LEC1.ppt and LEC2.ppt changed and no longer points to the full video. Try the above link.

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Telecom regulation• 1910 – Manns Elkins Act of 1910

– Telephone• 1927 - Radio Act of 1927

– Federal Radio Commission replaces Department of Commerce to regulate radio– Radio licensing

• 1934 – Communications Act of 1934– FCC replaces Interstate Commerce Commission (telephone) and Federal Radio

Commission (radio) to regulate wire (telephone) and radio– Title II – Common Carriers

• 1996 – Telecommunications Act of 1996– First major overhaul of American Telecommunications policy in 62 years

• 2001 – Patriot Act– “Uniting and Strengthening America by Providing Appropriate Tools Required to

Intercept and Obstruct Terrorism Act of 2001“• 2010 – FCC Open Internet Order• http://www.fcc.gov/guides/open-internet-transparency-rule

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The Communications Act of 1934

• The Communications Act of 1934 is a United States federal law, signed into law by President Franklin D. Roosevelt on June 19, 1934, and codified as Chapter 5 of Title 47 of the United States Code, 47 U.S.C. § 151 et seq. The Act replaced the Federal Radio Commission with the Federal Communications Commission (FCC). It also transferred regulation of interstate telephone services from the Interstate Commerce Commission to the FCC.

• The stated purposes of the Act are "regulating interstate and foreign commerce in communication by wire and radio so as to make available, so far as possible, to all the people of the United States a rapid, efficient, nationwide, and worldwide wire and radio communication service with adequate facilities at reasonable charges, for the purpose of the national defense, and for the purpose of securing a more effective execution of this policy by centralizing authority theretofore granted by law to several agencies and by granting additional authority with respect to interstate and foreign commerce in wire and radio communication, there is hereby created a commission to be known as the 'Federal Communications Commission', which shall be constituted as hereinafter provided, and which shall execute and enforce the provisions of this Act."

• On January 3, 1996, the 104th Congress of the United States amended or repealed sections of the Communications Act of 1934 with the new Telecommunications Act of 1996. It was the first major overhaul of American telecommunications policy in nearly 62 years.

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Lecture Notes

• You now have:– LEC1.ppt, LEC2.ppt, LEC3.ppt, LEC4.ppt,

CH1v6.ppt, CH2v6.ppt

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Current reading list

• Read Chapters 1,2,3,4,5,7,8,9 (Versions 5 and 6)• Read Chapters 1,2,3,4,5,8,9,11(Old Version 4)

• No assigned due date (reference class discussion)

Articles

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USA F _ E _ D _ _ A _ _

• What is the USA F _ E _ D _ _ A _ _ ? (ref Patriot Act assignment)

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The Patriot Act6/1/15

• http://www.cnn.com/videos/politics/2015/05/22/the-patriot-act-explained.cnn

• http://www.npr.org/sections/alltechconsidered/2015/06/04/411870819/phone-carriers-are-tight-lipped-over-law-that-overhauls-nsa-surveillance

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Patriot Act vs Freedom ActMay 2015

• The USA Freedom Act would put new constraints on how the government could obtain records under the PATRIOT Act and other national security laws. Instead of obtaining massive troves of data in bulk, the NSA could only ask companies for data on a specific entity like a person, account or device. And the government would have to show that the individual is associated with a foreign power or terrorist group.

• The measure also would change the law to allow surveillance to continue on terrorism suspects after they enter the U.S. And the bill would extend two other parts of the PATRIOT Act set to expire at midnight — “lone wolf” provisions designed to target terrorists acting individually, and “roving wiretap” provisions that let surveillance follow suspects even if they frequently change communications devices.

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Cyber

• Cyber is a prefix used to describe a person, thing, or idea as part of the computer and information age.

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How can we represent an image digitally?(review)

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How many bits?

• How many total bits will it take to represent the entire image screen in the slide above if the display pixels have two possible colors (black and white)?

• How many total bits will it take to represent the entire image screen in the slide above if the display pixels have three possible colors (black ,white, and yellow)?

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Telecommunicationsdigital

• Telecommunications: communicating over a distance

• How to communicate (over a distance):– Voice– Data– Image– Video

Digital

• How to represent data digitally

“Clickin”

• What can we use clickers for?

“Representin”

• Binary representation of text/data

• What is a bit?

Telecommunicationsdigital

• Telecommunications: communicating over a distance

• How to communicate (over a distance):– Voice– Data– Image– Video

Group exercise

• Santa needs to select a reindeer to guide his sleigh• The reindeer will listen for a click (1?) or no-click

(0?) • Use a sequence of clicks and no-clicks (bits) to call

the winning reindeer (create a table of reindeer names and codes)

• (1) If each reindeer must be represented by the same number of bits, what is the minimum number of bits needed to call the winner (assuming Rudolph is not included).

• (2) What are the results if any reindeer can win

How many bits are needed?(minimum number of bits)

• How many bits are needed to represent the 26 letters of the alphabet (caps only) ?

(see next slide for answer)

# of outcomes

• 2n = number of possible outcomes, where n is the number of bits

How many bits are needed?

• 2n = # of possible outcomes

• 2n >= 26

• If n=4, 2n = 2 x 2 x 2 x 2 = 16 (not enough)

• If n=5, 2n = 2 x 2 x 2 x 2 x 2 = 32 (enough)

• 32 – 26 = 6 extra outcomes can be used for other things if desired

• Answer a minimum of 5 bits are needed to represent the 26 letters of the alphabet

Text representation (data)7 bit ascii table

Binary Oct Dec Hex Character

100 0000 100 64 40 @

100 0001 101 65 41 A

100 0010 102 66 42 B

100 0011 103 67 43 C

Binary Oct Dec Hex Character

110 0000 140 96 60 `

110 0001 141 97 61 a

110 0010 142 98 62 b

110 0011 143 99 63 c

Panda

• Text v4 chapter 8 / Text v6 chapter 7

Chapter 2

• CH2v6.ppt

Metaphors• In computing, a metaphor is an icon or image used as

representative or symbolic of a computation

• When designers create a technology, they use metaphors to help users know how to operate their devices without reading a manual

• Example: The desktop metaphor was used by Apple in its Macintosh. This has been a very successful metaphor (with icons representing documents and folders, direct manipulation etc.) and it has been used in a lot of systems since, e.g. in Microsoft's Windows, a lot of graphical workstations etc.

– Example: The trash can metaphor fits nicely into the desktop metaphor. Other business metaphors: files, folders, documents

Instance

• An INSTANCE is one of whatever kind of information the application processes

• A word processor instance is a document

• For MP3 players, an instance is a song

• An instance for a photo editor is a picture

Interface

• What is an interface?

Define: interface

• The boundary/linkage between two things, such as the computer and a peripheral. Common interfaces for peripherals are the serial and parallel ports.

• The common boundary between two substances such as a water and a solid, or two liquids such as water and oil.

• The meeting point between a computer and something or (someone) outside of it. Common interfaces for people are the monitor screen and keyboard.

What not to like about a watch setting interface?

What’s not to like?

Awesome Interface ?

Stingray at Virginia Aquarium

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Next week

• The first webpage assignment will be explained next week (step by step)

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