How does the INTERNET work? | ICT #2

Summary

This video script offers an insightful journey into the workings of the internet, explaining how data travels from a Google Data Center to a user's device. It clarifies why satellite communication isn't viable due to latency issues and instead highlights the crucial role of optical fiber cables in connecting data centers to devices. The script delves into the concept of IP addresses, the function of DNS as the internet's 'phone book,' and how data is packetized and routed efficiently across the globe. It also touches on the management of the internet by ICANN and the protocols that govern data packet transmission, providing a comprehensive overview of the internet's infrastructure and operations.

Takeaways

• 🌐 The Internet's infrastructure involves data centers storing videos and other content, which are accessed through a network of optical fiber cables.
• 📶 Satellites are not commonly used for data transmission due to the high latency caused by the long distance signals must travel.
• 🌟 Optical fiber cables are the backbone of the Internet, providing a complex network that connects data centers to end devices.
• 🔢 IP addresses are unique identifiers for every device on the Internet, functioning like a home address for routing data.
• 🏠 Your Internet Service Provider (ISP) assigns an IP address to your device, which can be found by the user.
• 🌐 Servers within data centers store websites and content, and have their own IP addresses for accessing the stored data.
• 🔖 Domain names like 'youtube.com' are easier to remember than IP addresses and are used to access websites via DNS, which translates domain names into IP addresses.
• 🌍 ICANN, an institution in the USA, manages global Internet resources such as IP address assignment and domain name registration.
• 📦 Data is transferred in digital format via optical fiber cables in the form of light pulses, which may travel long distances.
• 📈 The efficiency of the Internet comes from breaking data into small packets, which are transmitted and reassembled at the destination, allowing for the best routing paths.
• 🛑 Internet protocols set the rules for data packet management, including conversion, addressing, and routing, ensuring orderly data flow.

Q & A

How does a video stored in a Google Data Center reach my mobile phone?

A video stored in a Google Data Center reaches your mobile phone through a complex network of optical fiber cables rather than satellites, due to the significant delay and latency issues associated with satellite transmission.

Why are satellites not an ideal method for transmitting data from data centers to mobile devices?

Satellites are not ideal because they are located approximately 22,000 miles above the Earth's equator, causing data to travel a total distance of 44,000 miles and resulting in unacceptable latency for most internet applications.

What is the role of optical fiber cables in the internet infrastructure?

Optical fiber cables form a network that connects data centers to devices like mobile phones and laptops, allowing for the efficient transmission of data in the form of light pulses.

What is an SSD and how does it relate to the storage of videos in a data center?

An SSD, or Solid-State Drive, acts as the internal memory of a server within a data center. It is where videos and other content are stored before being served to users upon request.

What is the purpose of a server in a data center?

A server in a data center is a powerful computer designed to store and provide access to content, such as videos, when a user requests it.

Can you explain the concept of an IP address in the context of the internet?

An IP address is a unique string of numbers assigned to every device connected to the internet, serving as a 'shipping address' to ensure that information reaches its intended destination.

Why are domain names used instead of IP addresses?

Domain names like 'youtube.com' are used instead of IP addresses because they are easier for humans to remember and manage. They correspond to IP addresses, which are resolved through the Domain Name System (DNS).

What is the function of the Domain Name System (DNS)?

The DNS acts as a 'phone book' for the internet, translating human-friendly domain names into IP addresses that computers use to locate and access websites.

How is data transferred through optical fiber cables?

Data is transferred through optical fiber cables in digital format, specifically in the form of light pulses that travel potentially thousands of miles to reach their destination.

What is the role of a router in accessing the internet?

A router converts the light signals from optical fiber cables into electrical signals, which are then transmitted to devices such as laptops via Ethernet cables or to mobile phones via Wi-Fi.

How does the internet manage global tasks like IP address assignment and domain name registration?

These global tasks are managed by an institution called ICANN, which oversees IP address assignment, domain name registration, and other critical functions of the internet infrastructure.

What is the significance of data packets in the transmission of information over the internet?

Data packets are small chunks of data that contain bits of information along with sequence numbers and IP addresses. They are efficiently routed and reassembled at the destination, allowing for reliable data transmission even if some packets are lost or delayed.

What are protocols in the context of internet data transmission, and why are they important?

Protocols are the rules that govern the management of data packet flow, including data packet conversion, attachment of source and destination addresses, and the functioning of routers. They are essential for maintaining order and efficiency in internet communications.

Outlines

00:00

🌐 Understanding the Internet's Infrastructure

This paragraph delves into the complex journey data takes to reach a user's device from a data center, such as Google's. It explains the impracticality of using satellites due to the significant latency caused by the long distance the signals must travel. Instead, the paragraph highlights the crucial role of a global network of optical fiber cables that connect data centers to end-user devices. The paragraph also introduces the concept of solid-state drives (SSDs) as the storage medium within data centers and the role of servers as powerful computers that serve up content upon request. Additionally, it sets the stage for understanding the transfer of data through the complex network of cables by introducing the concept of an IP address, which uniquely identifies each device on the Internet, similar to a home address.

05:01

🌐 The Journey of Data Packets Across the Internet

The second paragraph focuses on the process of data transfer over the Internet, starting from the server in the data center to the user's device. It describes how data is transferred in digital format through optical fiber cables as light pulses, which may traverse challenging terrains like under the sea or through mountains. The paragraph introduces the role of global companies in laying and maintaining these crucial optical cable networks and explains how these cables are laid using ships and plows to create trenches on the seabed. It also touches on the conversion of light signals to electrical signals by routers and the subsequent transmission to devices via Ethernet cables or cell towers. The paragraph further explains the global management of the Internet by organizations like ICANN and the efficiency of data transmission through the division of data into packets. It details the packet routing process, including the use of sequence numbers and IP addresses, and the reassembly of packets at the destination device. Lastly, it compares the Internet's efficiency to a postal network and emphasizes the importance of protocols in managing data packet flow.

Keywords

💡Internet

The Internet is a global network of interconnected computers and servers that communicate with each other using standardized protocols. It is the backbone of modern communication and information exchange. In the video, the Internet is the central theme as it explains how data travels from a Google Data Center to a user's device, highlighting its infrastructure and the technology that makes communication possible.

💡Data Center

A Data Center is a facility that houses a large number of servers used for storing, processing, and distributing data. In the context of the video, the Google Data Center is where the video content is stored before it is transmitted to users. It represents the starting point of the data's journey to the end-user.

💡Optical Fiber Cables

Optical Fiber Cables are thin strands of glass or plastic designed to transmit information as pulses of light over long distances. They form the physical infrastructure that connects different parts of the Internet. The video explains that these cables are used to transmit data from the data center to the user's device, emphasizing their role in the efficiency and speed of data transmission.

💡IP Address

An IP Address is a unique numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication. It serves as the device's identifier and location identifier on the network. The video script mentions IP addresses as the unique identifiers for servers and devices, crucial for routing data packets to their correct destinations.

💡Domain Name

A Domain Name is a human-readable string of characters that represents an IP address on the Internet. It allows users to access websites without needing to remember numerical IP addresses. The video script explains the use of domain names like 'youtube.com' and 'facebook.com' as easier-to-remember alternatives to IP addresses.

💡DNS (Domain Name System)

DNS, or Domain Name System, is the phone book of the Internet. It translates human-friendly domain names into IP addresses that computers use to identify each other on the network. The video describes how the DNS server provides the service of mapping domain names to IP addresses, facilitating the user's ability to access websites.

💡Server

A Server is a powerful computer or system designed to process requests, store data, and deliver content to other computers or devices, known as clients. In the video, the server is the device within the data center that stores the video content and delivers it to the user upon request.

💡Packets

Packets are units of data that are sent through a network. They are the building blocks of data transmission in the Internet, containing bits of information along with routing information. The video script explains how data is divided into packets, each with its own sequence number and IP addresses, to be efficiently transmitted and reassembled at the destination.

💡Router

A Router is a networking device that forwards data packets between computer networks. It uses routing tables and protocols to determine the best path for data to travel. The video mentions routers as the devices that convert light signals from optical fiber cables into electrical signals, directing them towards the user's device.

💡ICANN

ICANN, the Internet Corporation for Assigned Names and Numbers, is a non-profit organization responsible for coordinating the maintenance and procedures of several databases related to the namespaces of the Internet. The video script notes ICANN's role in managing IP address assignments and domain name registrations, which are essential for the functioning of the Internet.

💡Protocols

Protocols are a set of rules governing the format and transmission of data on the Internet. They define the standards for data packet conversion, addressing, and routing. The video script highlights the importance of protocols in managing the complex flow of data packets, ensuring that data is transmitted and received correctly.

Highlights

The video explains the journey of data from a Google Data Center to your device.

Satellite transmission is not ideal due to the long distance and latency.

Optical fiber cables form a complex network connecting data centers to devices.

Devices connect to the internet via cellular data or Wi-Fi, ultimately linking to optical fiber cables.

Data is stored in solid-state devices (SSDs) within data centers, acting as server memory.

Servers are powerful computers that provide content when requested.

IP addresses uniquely identify every device connected to the Internet.

IP addresses function similarly to home addresses for routing data.

Domain names like youtube.com are easier to remember than IP addresses.

Host headers are used to identify websites on servers with multiple sites.

DNS servers act as a 'phone book' for the Internet, translating domain names to IP addresses.

Data is transferred in digital format via optical fiber cables as light pulses.

Optical fiber cables are laid undersea and across terrains by global companies.

Routers convert light signals from optical fibers to electrical signals for devices.

Cellular data sends signals from optical cables to cell towers and then to mobile phones.

ICANN manages IP address assignment and domain name registration globally.

Data transfer efficiency is achieved by chopping data into packets with sequence numbers and IP addresses.

Packets are routed independently and reassembled at the destination based on sequence.

Protocols set rules for data packet management, ensuring efficient data flow.

Transcripts

How does the internet work?

The video you are watching now

traveled thousands of miles from a Google Data Center to reach you.

Let's learn how the internet works by getting to understand the details of this data's incredible journey.

The data center which can be thousands of miles away from you has your video stored inside it.

how does this data reach your mobile phone or a laptop?

An easy way to achieve this goal would be with use of satellites.

From the data center, a signal could be sent to the satellite via an antenna,

and then from the satellite a signal could be sent to your mobile phone

via another antenna near to you.

However, this way of transmitting signals is not a good idea.

Let's see why.

The satellite is parked nearly 22,000 miles above the earth's equator,

so in order for the data transmission to be successful,

the data would have to travel a total distance of 44,000 miles.

Such a long distance of travel causes a significant delay in receiving the signal.

More specifically it causes huge latency which is unacceptable

for most internet applications

so if this video does not reach you via a satellite then

how does it actually get to you?

Well it is done with the help of a complicated

network of optical fiber cables,

which connect between the data center and your device.

Your phone could be connected to the internet via cellular data or any Wi-Fi router,

but ultimately at some point your phone will be connected

to this network of optical fiber cables

We saw at the beginning that the video you are currently watching

is stored inside a data center.

To be more specific, it is stored in a solid-state device within the data center.

This SSD acts as the internal memory of a server.

The server is simply a powerful computer whose job is to provide you the video or

other stored content when you request it.

Now the challenge is how to transfer the data stored

in the data center specifically to your device via the

complex network of optical fiber cables.

Let's see how this is done.

Before proceeding further we should first understand an important concept

which is the concept of an IP address.

Every device that is connected to the Internet

whether it is a server a computer or a mobile phone is identified uniquely by a

string of numbers known as an IP address.

You can consider the IP address similar

to your home address that is the address, that uniquely identifies your home.

Any letter sent to you reaches you precisely because of your home address.

Similarly in the internet world an IP address acts as a shipping address

through which all information reaches its destination.

Your internet service provider will decide the IP address of your device and you are able to see what

IP address your ISP has given to your mobile phone or laptop.

The server in the data center also has an IP address.

The server stores a website so you can access any website just by knowing the

server's IP address. However, it is difficult for a person to remember so

many IP addresses.

So to solve this problem domain names like

youtube.com, facebook.com etc are used which correspond to IP addresses

which are easier for us to remember than the long sequence of numbers

Another thing to notice here is that a server has the capability of storing several websites

and if the server consists of multiple websites all the websites cannot be

accessed with the server's IP address.

In such cases additional pieces of

information, host headers are used to uniquely identify the website.

However, for the giant web sites like Facebook.com or YouTube.com the entire data

center infrastructure will be dedicated to the storage of the particular website.

To access the internet we always use domain names instead of the complex IP address numbers.

From where does the internet get IP addresses corresponding to our domain name requests.

Well, for this purpose the internet uses a huge phone book known as DNS.

If you know a person's name, but don't know their telephone number

you can simply look it up in a phone book.

The DNS server provides the same service to the internet.

Your internet service provider or other organizations can manage the DNS server.

Let's have a recap of the whole operation.

You enter the domain name,

the browser sends a request to the DNS server to get the corresponding IP address.

After getting the IP address,

your browser simply forwards the request to the data center,

more specifically to the respective server.

Once the server gets a request to access a particular website the data flow starts.

The data is transferred in digital format via optical fiber cables,

more specifically in the form of light pulses.

These light pulses sometimes have

to travel thousands of miles via the optical fiber cable to reach their destination.

During their journey they often have to go through tough terrains

such as hilly areas or under the sea.

There are a few global companies who lay

and maintain these optical cable networks.

These visuals show how the laying of optical fiber cables is done with the help of a ship.

A plow is dropped deep into the sea from the ship,

and this plow creates a trench on the seabed and to which places the optical fiber cable.

In fact, this complex optical cable

network is the backbone of the Internet.

These optical fiber cables carrying the

light are stretched across the seabed to your doorstep where they are connected to a router.

The router converts these light signals

to electrical signals.

An Ethernet cable is then used to

transmit the electrical signals to your laptop.

However if you are accessing the Internet using cellular data,

from the optical cable the signal has to be sent to a cell tower

and from the cell tower the signal

reaches your cell phone in the form of electromagnetic waves.

Since the Internet is a global network it has become important to have an

organization to manage things like IP address assignment, domain name registration etc

this is all managed by an institution called ICANN located in the USA.

One amazing thing about the internet is its efficiency in

transmitting data when compared with cellular and landline communication technologies.

This video you are watching from the Google Data Center is sent to

you in the form of a huge collection of zeros and ones.

What makes the data transfer in the internet efficient is the way in which these zeros and ones

are chopped up into small chunks known as packets and transmitted.

Let's assume these streams of zeros and ones are divided into different packets by the

server where each packet consists of six bits.

Along with the bits of the video each packet also consists of the sequence

number and the IP addresses of the server and your phone.

With this information the packets are routed towards your phone.

It's not necessary that all packets are routed through the same path and each packet independently

takes the best route available at that time.

Upon reaching your phone the packets are reassembled according to their sequence number.

If it is the case that any packets fail to reach your phone and acknowledgement

is sent from your phone to resend the lost packets.

Now compare this with a postal network

with a good infrastructure, but the customers do not follow the basic rules

regarding the destination addresses.

In this scenario letters won't be able to

reach the correct destination.

Similarly in the internet we use something called protocols for the

management of this complex flow of data packets.

The protocols set the rules for

data packet conversion, attachment of the source and destination addresses to each packet

and the rules for routers etc for different applications the protocols

used are different.

We hope this video has given you a good understanding about how the internet works,

more specifically about the amazing journey of data packets

from the data center to your mobile phone.

Please don't forget to support us at patreon.com. Thank You!