Audio Transcript Auto-generated
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Good morning everyone
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today
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I will talk to you about the internet infrastructure.
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So
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what will I tell you about precisely
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firstly
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I will tell you about the definition of internally
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moreover
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about packets, routing availability
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I. P. Addresses indians
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and lastly
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http and html.
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So
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what's the internet?
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The internet is a tangible physical system that was made to move information.
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Internet ships, binary
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information made of bits
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because of it has two possible states.
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We call it binary code.
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It beats correspond to one bite,
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1024 Bytes,
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one kilobyte etcetera.
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Fights are the items and information
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today we physically send bits by electricity. Light and radio waves
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to send information faster.
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We need to increase the bandwidth
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which is the maximum transmission capacity of a device
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bandwidth is measured by bitter it
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which is the number of bits
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that we can send over a given period of time. Usually measured in seconds.
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A different measure of speed is the lead agency which is the amount of
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time it takes for a bit to travel from one place to another.
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So
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with what sort of cable can you send? This message is over
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with electricity
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which is cheap but
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it has a signal loss light which is really fast.
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It doesn't have signal loss but it's very expensive and it's hard to work
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with or radio which is totally mobile but it has a short range.
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How does information get transferred from one computer to another
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Information on the internet because from one computer to another
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in what we call packet of information
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A pack it travels from one place to
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100 on the Internet depending on traffic congestion
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or road condition. You might choose or be forced
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to take a different route
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to get to the same place.
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Many kinds of digital information
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can be sent with iP packets
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but there are some limits.
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Since it's that on a computer the
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computer can send information into smaller packets.
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Each packet has the internet address of where it came from, january school
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special computers on the internet called boaters
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act like traffic managers to keep the packets moving
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to the network smoothly.
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If one route is congested,
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individual packets may travel different routes
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to the internet and may arrive at the destination
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at slightly different times or even out of work,
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how does it work?
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Every order
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keeps track of multiple paths for sending packets
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and they choose the cheapest based on destination
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address for the bucket
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having options for paths.
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Makes the network fault tolerant,
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which means the network and keep sending packets
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even if something was horrible.
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This is the basis for a key principle of the internet.
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Where are you based?
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What if you request on data and not everything is delivered.
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Thanks to the CCP which stands for transmission control protocol,
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everything you request will arrive to.
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How does the TCP work
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when your packets arrive
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disappeared as a full inventory,
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it sends back acknowledgements of each package received.
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If all packets are their TCP signs for
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your delivery and you're done.
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If TCP finds some packets are missing, it won't say anything
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Back in the 1970s. There was no standard method for networks to communicate.
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It took the work of vince cerf and bob
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Kahn to invent an enter work inter networking protocols
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to make communication possible.
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The internet is a design of philosophy
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and then architecture expressed in a lot of protocols.
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A protocol is a well known set of rules and standard
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that if all parties agrees to use it,
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it will allow them to communicate without trouble.
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All the different devices on the internet have unique addresses,
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addresses on the internet
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is just
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a number similar to a phone number
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or a sort of a street address
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that's unique to each computer or device
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at the edge of the network.
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A computer's address
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it's called its I. P. Address
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visiting our website
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is really just your computer asking another computer for information.
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Your computer sends a message
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to the other computer's IP address
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and it also sends along its original address.
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So the other computer
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knows where to send its responses.
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Traditional I.
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P addresses are 32 bits longer with eight bits for each part of the addresses.
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There are two types of
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I. P addresses.
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There is I. P. V. Four which is a version of I. P. Addressing designed in
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1973
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And was widely adopted in the early 80s
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and provides for more than four billion unique
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addresses for devices connecting to the Internet.
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We are now in the middle of a multi year transition to a longer I. P. Address
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Format called i. p. v. 66
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which uses that
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128 bits
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parameters and provides over
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340
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and the Sicilian unique addresses.
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Your computer uses the DNS which stands for domain name system
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to look up domain names and get the associated I.
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P.
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Because of its openness.
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DNS is success doble to cyberattacks
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which means
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that people can
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heck you
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how do the computers all across the world actually communicate with each other?
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Let's look at web browsing
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firstly. You open a web browser
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that you used to access the web based
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such as chrome
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edge.
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Then you type in the web address or you are
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l which stands for uniform resource locator of the website.
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You want to visit.
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Your computer starts talking
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to another computer
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called server.
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And in milliseconds your computer asked the server for a website
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and that server starts talking to your computer in a language called http
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which stands for hypertext transfer protocol.
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Html
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stands for hypertext markup language.
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And you can think of it
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as the language you used to tell a web browser how to make a page look.
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But how does a website remember who you are?
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Thanks to cookie data.
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The internet is completely open.
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Its connections are shared
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and its information is sent in plain text
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which means that hacker may snoop on any of
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your personal information that you send on the Internet.
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But websites prevent this by asking your Web browser to communicate
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on a secure channel using something called the secure sockets layer
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and its successor transport layer security.