you open the browser type in your favorite website press enter and just like magic you can help the new and

improved Zuckerberg 2.0 sell your private data to the highest bidder while watching motivational reals while the

psychology behind finding joy in Mindless scrolling is quite interesting this is a tech channel so in the next

couple of minutes we'll look at the magic part that makes wasting our lives on the internet possible despite the

apparent Simplicity of accessing a website what you might not realize is that there is a long history of hard

manual labor and fascinating Tech Innovations behind the seamless process of navigating the web we all know that

the internet is a massive network of interconnected computers locally your device might be linked to the network

via Wi-Fi 5G or even a satellite dish on a global scale however around 99% of the world's international data is

transmitted through thousands of miles of fiber optic cables stretching across continents and oceans these cables are

about the size of a garden hose and they are protected by layers of insulation and steel to withstand damages from

fishing net ship anchors and natural events like earthquakes laying these cables is no small Feit picture massive

ships slowly laying cables across the ocean floor navigating underwater mountains and trenches it's a process

that takes years of planning billions of dollars and the kind of patience most of us lost in the age of 10 seconds Tik Tok

videos once these cables are in place they connect Massive data centers spread across continents which require

industrial strength AC sees and liquid cooling while consuming more electrical power than a small town if this sounds

like an exaggeration remember that the average Google data center consumes enough electricity to power 200,000

homes annually as you can imagine the utility bills for these facilities can easily get overwhelming so many data

centers are built in cold places like Iceland or Finland to save on cooling costs and this is just the physical side

of the internet the software protocols algorithms and Engineering behind this infrastructure are even more fascinating

so when you access a website you are looking for that website server in a very complex network of millions of

interconnected nodes each uniquely identified through a combination of numbers called an IP IPS are quite

harder to remember for humans so we use uniform resource locators instead URLs are strings that follow a strict pattern

with a scheme indicating the use protocol and Authority composed of the domain name and the port the path to the

resource a list of parameters where additional data is sent as key value Pairs and a fragment referring to a

specific part of the document once you press enter the first thing the browser does is to map the URL to an existing IP

address these mappings are managed by the domain name system the DNS acts like a huge phone book for the internet

translating human readable domain names into machine readable IP addresses this process is called DNS resolution and

involves several steps first your browser checks its cache to see if it already knows the IP address if not it

asks your operating system which in turn queries a DNS resolver usually provided by your internet service provider or a

public service like Google or Cloud flare the resolver might also have the address cached if it doesn't it starts a

series of queries climbing up the DNS hierarchy it all begins with the root DNS server this is the system that

actually drives the entire internet what's interesting is that it is composed of only 13 servers distributed

across the planet the number might seem low but each of these instances is part of a large network of over 1500 physical

servers distributed globally to ensure redundancy and resilience the route points the resolver to the top level

domain servers associated with the domain the user is looking for this can be.org or any of the other hundreds of

possible extensions these TLD servers then direct the resolver to the authoritative name server for the

specific domain finally the authoritative name server provides the IP address and this is returned to your

browser now that the browser has the IP address the real work can finally begin remember that all these steps are done

by sending information through light over thousands of miles of fiber optic cable in milliseconds just so that

someone has the best user experience possible when they swipe left you since the channel of communication between our

browser and the server is pulsing light traveling through fiber optic cable at 200,000 km/ second the exchange data has

to be divided in very small chunks called packets that can easily travel in this medium the primary responsibility

of tcpip is to create these packets and send them to their final destination ensuring the packets can be put back

together on the other end of the communication packet management is a complex and fascinating topic involving

segmentation sequencing and error handling definitely deserving of its own video to give you a sense of the

complexity involved in managing packets note that each packet of data is typically 1500 bytes so if you're

streaming a 1 GB movie that's over 700,000 packets being sent to your device for the purpose of this

discussion it is enough to know that TCP allows data to be transferred reliably to its destination both the sender and

the receiver must agree on connection parameters before actually establishing the connection in a process known as a

three-way handshake procedure first the client informs the server that it wants to establish a connection by sending a

synchronized package then the server responds with an acknowledgement package and finally the client sends back

another acknowledging message of course each step is done via the network so these packets have to Traverse the

entire distance between the client and the server for each step of the handshake crazy stuff so at this point

your packets might have covered a distance similar to the entire circumference of the world but we are

still far away from receiving and displaying the page in the browser once the TCP connection is established in a

process that feels like an eternity but it actually takes just a few milliseconds the client and server can

finally exchange messages using the hypertext transfer protocol or even better its secure extension this is

where the transport layer security handshake often comes into play ensuring that your data is encrypted and secure

this handshake is performed through another round of server client communication steps once the browser's

request is approved the server will usually send back a success response along with the requested resource when

the first request is made from the client the first packet that arrives as response marks the time to First Bite

this is an important metric that represents the time elapsed since the request was initiated and when the first

chunk of data was received as a response it includes the time taken for the DNS lookup the TCP handshake to establish

the connection and the TLs handshake if the request is made over https once the browser received the server's response

it begins processing the data the HTML structure is parsed external resources like CSS and JavaScript are fetched and

everything is assembled into the web page you see this process known as rendering transforms raw data into the

user interface and is a story for another day if you enjoy this type of content you should check some of my

other videos until next time thank you for watching [Music]