Internet Hardware

Summary

This video script offers a comprehensive overview of the Internet's hardware infrastructure, explaining how networks are interconnected through physical systems. It clarifies that the Internet is a vast network of routers, not a single entity, and delves into how data is transmitted via electricity, light, and radio waves. The script also touches on crucial concepts like bandwidth, bitrate, and latency, which are essential for understanding data transmission speeds and delays. By simplifying complex technical details, the script aims to make the functioning of the Internet more accessible.

Takeaways

• 🌐 The Internet is a network of networks, connecting individual networks through a vast system of routers.
• 💻 A network is a group of two or more computer systems linked together for data exchange.
• 🔌 To scale networks beyond simple connections, routers are used as middlemen to manage data traffic.
• 🏠 For small networks like homes or schools, a single router can manage connections, but for larger networks, multiple routers are required.
• 🌐 The Internet is not a single router but a massive network of interconnected routers, each only connected to a few others.
• 📡 Internet Service Providers (ISPs) provide the routers that individual networks connect to, like Comcast or AT&T.
• 🔢 Data is transmitted across the Internet as digital information, represented as a series of zeros and ones.
• 💡 The physical representation of these zeros and ones can be through electricity (Ethernet cables), light (fiber-optic cables), or radio waves (Wi-Fi, cellular).
• 🚀 Fiber-optic cables are used for long-distance data transmission due to their ability to cover vast distances with minimal signal degradation.
• 📶 Radio waves facilitate wireless communication, used in Wi-Fi and cellular networks, but are limited by short transmission distances.
• 🕒 Latency is a critical factor in network performance, referring to the time it takes for a bit to travel from sender to receiver, with fiber-optic cables offering the lowest latency.

Q & A

What is the Internet?

The Internet is a network that connects individual networks, allowing for the exchange of information between devices.

What is a network?

A network is a group of two or more computer systems that are linked together, enabling the sharing of information.

Why is it impractical to connect every device directly to every other device?

Directly connecting every device to every other device is not scalable due to the exponential increase in connections required as the number of devices grows.

What is a router and how does it simplify network connections?

A router is a networking device that forwards data packets between devices connected to it. It simplifies connections by allowing each device to connect to a single router instead of every other device.

How does the Internet handle connections between many local networks?

The Internet connects many local networks by using a vast network of interconnected routers, where each router is connected to only a few others.

What is an Internet Service Provider (ISP) and what role do they play?

An Internet Service Provider is a company that provides access to the Internet by offering routers for individual networks to connect to. Examples include Comcast and AT&T.

How is information represented and sent across the Internet?

Information is represented as binary code, using zeros and ones, which are then sent across the network using various physical methods.

What are the three main methods used to send information from one computer to another?

The three main methods are using electricity (e.g., Ethernet cables), light (e.g., fiber optic cables), and radio waves (e.g., Wi-Fi and cellular networks).

Why is it necessary to use a clock in digital communication?

A clock is used to synchronize the sending and receiving of bits, ensuring that the sender and receiver agree on the timing of bit transmission to avoid data corruption.

What is bandwidth and how is it measured?

Bandwidth is the capacity of data transfer in a system, measured by bitrate, which is the number of bits that a system can send in one second.

What is latency and why is it important in networks?

Latency is the time it takes for a single bit to travel from the sender to the receiver. Low latency is desirable for fast and efficient network communication.

Outlines

00:00

🌐 Understanding the Internet's Hardware

This paragraph introduces the concept of the Internet as a network of networks, connecting individual computer systems through various hardware systems. It explains the scalability issue with direct connections between computers and how routers act as middlemen to efficiently manage data transmission. The discussion then moves to the Internet's structure, which is a vast system of interconnected routers rather than a single entity. The paragraph concludes by emphasizing the role of Internet Service Providers (ISPs) in providing access points for local networks to connect to the global Internet. The core functionality of the Internet is described as the transmission of digital information, encoded as binary data (zeros and ones), highlighting the use of electricity, light, and radio waves as the primary methods for sending bits across the network.

05:01

🚀 Exploring Data Transmission Methods

This paragraph delves into the three main methods of data transmission over the Internet: electricity, light, and radio waves. It explains how Ethernet cables use electrical signals to represent binary data, with high and low voltages for zeros and ones, respectively. The use of fiber optic cables for long-distance data transmission through light signals is discussed, emphasizing their high cost and effectiveness over vast distances. The paragraph also covers the use of radio waves for wireless communication, as seen in Wi-Fi and cellular networks, which have the advantage of wireless connectivity but are limited by short transmission ranges. The concept of a 'clock' is introduced to synchronize bit transmission and reception, ensuring data integrity. The importance of bandwidth and bitrate in determining data transfer speed is highlighted, with examples provided to illustrate the difference between low and high bandwidth scenarios. Lastly, the paragraph introduces the concept of latency, which is the time taken for a bit to travel from sender to receiver, and how it varies with the transmission medium used.

10:03

🌌 The Physical Backbone of the Internet

In this concluding paragraph, the focus is on the physical infrastructure that enables the Internet to function. It summarizes the key points discussed in the previous paragraphs, emphasizing that the Internet relies on a combination of electrical, optical, and wireless technologies to transmit data across the globe. The paragraph reiterates that the Internet is built on a foundation of physical hardware, which includes the various methods of sending bits—through electrical currents in Ethernet cables, light pulses in fiber optic cables, and radio waves in Wi-Fi and cellular networks. The summary reinforces the idea that the Internet's global reach is made possible by the sophisticated interplay of these technologies, which work together to send and receive data across vast distances.

Keywords

💡Internet

The Internet is a global network that interconnects various individual networks, allowing devices to communicate and share information. In the video, the Internet is described as a network of routers that connect smaller networks, such as home, school, or coffee shop networks, enabling communication between devices that are not directly connected. The script explains that the Internet is not a single entity but a complex system that facilitates the exchange of digital information across the globe.

💡Network

A network, as mentioned in the script, is a collection of two or more computer systems that are connected in some way. Networks can be as simple as two computers linked together or as complex as the Internet itself. The video uses the concept of networks to illustrate how data can be shared between devices, and how routers are used to manage the flow of information within and between these networks.

💡Router

A router is a networking device that forwards data packets between computer networks. In the context of the video, routers act as middlemen, allowing multiple devices to connect to the Internet without each device needing a direct connection to every other device. The script explains that routers solve the scalability problem of connecting numerous devices by managing the paths that data takes to reach its destination.

💡Bandwidth

Bandwidth refers to the maximum rate of data transfer across a given path. It is a critical concept in the video as it relates to the capacity of a network to transmit information. The script mentions that increasing bandwidth allows for faster data transfer, which is essential for activities like downloading songs or streaming videos. The video uses the term to explain the need for high-speed connections in modern networking.

💡Bitrate

Bitrate is the number of bits that a system can send per second, which is a measure of the data transfer speed. The video script uses bitrate to explain how the speed of data transmission is quantified. It contrasts low bitrates, like one bit per second, with higher bitrates, such as five megabits per second, to illustrate the difference in data transfer capabilities.

💡Latency

Latency is the time it takes for a single bit of data to travel from the sender to the receiver. In the video, latency is presented as a crucial factor in network performance, with lower latency indicating a faster and more efficient connection. The script provides examples of how different mediums, like fiber optic cables and Ethernet, affect latency due to the speed of light and electrical signals.

💡Electricity

Electricity is used in the video to describe one of the methods for sending bits of information over a network. Ethernet cables, for example, use electrical signals to transmit data. The script explains that by varying the voltage—high for a 1 and low for a 0—computers can send and receive digital information through electrical means.

💡Light

Light, specifically in the form of laser pulses, is used in fiber optic cables to transmit data. The video script highlights fiber optic cables as a means of sending information over long distances, such as undersea cables that connect continents. It explains that light signals are used to represent bits, with different light intensities corresponding to 0s and 1s.

💡Radio Waves

Radio waves are a wireless method of transmitting data, as discussed in the video in the context of Wi-Fi routers and cell towers. The script explains that radio waves can carry information through the air, with different frequencies representing 0s and 1s. This technology allows for wireless connectivity but is limited by its range and the need for a clear line of sight to the transmitter.

💡Encoding

Encoding in the video refers to the process of representing information as a series of binary digits (bits), which are the fundamental units of data in digital systems. The script explains that all information sent over the Internet, regardless of its original form, is encoded into bits as zeros and ones before being transmitted. This encoding process is essential for the digital transmission of data across networks.

Highlights

The Internet is a network that connects individual networks.

A network is a group of two or more computer systems linked together.

Connecting every pair of computers in a network is not scalable for large numbers of devices.

Routers act as middlemen to forward requests in a network.

The Internet is a massive network of interconnected routers.

Routers in the Internet are not connected to every single other router, only a few.

Internet Service Providers (ISPs) provide routers for individual networks to connect to the Internet.

Data transmission in the Internet involves encoding information into zeros and ones.

Electricity is used to send bits through Ethernet cables.

Light is used in fiber optic cables for long-distance data transmission.

Radio waves enable wireless data transmission through Wi-Fi and cellular networks.

A clock is introduced to synchronize bit sending and recording to prevent data loss.

Bandwidth is the capacity of data transfer in a system, measured by bitrate.

Latency is the time it takes for a bit to travel from sender to receiver.

Fiber optic cables offer the best latency due to the speed of light.

Ethernet connections are typically shorter and have higher latency compared to fiber optics.

The physical systems of the Internet include hardware for sending bits using electricity, light, and radio waves.

Transcripts

hi in this video we'll be learning about

the hardware of the Internet

the physical systems that the Internet

is built on so what is the Internet well

the Internet is a network that connects

individual networks what do I mean when

I say network

well introducing networks so a network

is a group of two or more computer

systems that are somehow linked together

so let's look at a simple network here

we have two computers and they share a

link that just means we can get

information from this computer send it

over the link and it is received on this

computer so that's great that's a simple

network it's two computers that are

connected now what happens when we have

four computers how can we connect all of

these well one solution is to simply

connect every pair of computers so now

each computer shares a link with every

other computer now this works but the

problem is this is not scalable when we

get to the point where we have hundreds

thousands millions of devices it's not

realistic for every device to have a

link to every single other device so the

solution is to introduce a middleman we

call it a router so in this scenario

each device only needs one connection it

needs to connect to the router then the

router takes care of actually forwarding

each request to the intended recipient

so if the top left computer wanted to

send a message to the bottom left

computer it would tell the router that

and the router would forward along that

message and this system is great for

small simple networks a single router

can connect computers that are close

together either in one room or in one

building now the problem is there exists

several of these small simple networks

and we need to be able to connect them

to each other so let's say one of these

is your home one of these is your school

and one of these is a coffee shop and we

need the ability for two computers in

separate local networks to send messages

to each other so the solution there is

to add another router that connects each

of the routers now there exists a path

from a computer in one network all the

way to a computer in a separate Network

now this solution is good for a small

number of simple networks but the

problem is once we have too many simple

networks one router can't handle it it's

too much so now we get to the Internet

now the Internet is not one big router

that connects all the individual

networks the internet is actually itself

massive network of routers and each

router is not connected to every single

other router it's only connected to a

few of them so it ends up being this

complicated interconnected system of

routers so that way when these

individual tiny networks say a house or

a coffee shop wants to connect to the

Internet it just needs to pick one

router and connect to it and so these

routers that the individual networks

connect to are provided by what's called

an Internet service provider so someone

like Comcast or AT&T now we don't really

have to worry about what's going on

inside this crazy network of routers

right now we're only worried about how

data is being transmitted in the

individual networks so for now let's

just abstract all that away call it the

Internet and just know that it is a

massive network that connects these

individual simple networks so that's

what we mean when we say that the

Internet is a network connecting

individual networks it is a big network

of routers that just has these endpoints

that you can connect to so really what

we're concerned with is sending

information that is the core

functionality of the Internet we want to

be able to get this smiley face from the

computer on the left all the way to the

computer on the right but what's

actually happening there we're not

actually sending a physical smiley face

across the network instead we're gonna

use the power of digital information

we're gonna use the power of encoding to

represent any information we want to

send as zeros and ones and that's what

we send across the network so what a

symbolic level the Internet is really

just a way to get zeros and ones from

point A to point B but the physical

level how is that actually happening how

can we represent a zero and one inside

the network this is where the internet

hardware comes in so we mainly use three

methods to send information from one

computer to the other and those three

methods are electricity light and radio

so how do we send bits with electricity

so you may have seen Ethernet cables and

Ethernet cables are simply copper wires

that were able to hook up to a computer

and send electricity through so the pros

of sending bits of electricity is that

it's cheap and the cons in that it only

covers medium distances we're not able

to send bits very far on an electric

cable before the signal starts to fade

it's the physical way that we send bits

using electricity is we just set the

wire to be a high voltage to represent

a1 and we set the wire to have a low

voltage

to represent zero and just switching off

between high and low voltages these

computers are able to tell whether a

zero or a one is being sent how about

sending bits with light well to do that

we use fiber optic cables and these are

the big guns these are the connections

that are going across oceans going

across continents most of the distance

covered on the Internet is through fiber

optic cables so the pros to fiber optic

cables is they can travel very long

distances they can travel across the

floor of the ocean the cons is that very

expensive this is why you're not really

going to use it for your home network or

for your coffee shop instead this is

what the Internet service providers are

using to transfer information between

the Internet routers so how do we

physically send bits with light well all

we have to do is set the connection to

have a bright light for one and a dim

light or no light for zero so the

computers can simply look at the state

of the connection and if it's bright

it's a 1 and if it's dim it's a zero how

about radio waves so how do devices send

bits using radio waves well real life

examples of sending bits with radio

waves include a Wi-Fi router which you

probably have in your home or your

school and a cell tower so this is what

cell phones are using to send bits

through the air using radio waves so the

pros with radio waves are that it's

wireless the cons are that it only

covers a very short distance you have to

be pretty close to a cell tower or to a

Wi-Fi router in order for your signal to

be picked up so how do radio waves

physically send zeros and ones well if a

computer wants to send a 1 it just

produces a high frequency wave so the

wave is very tight and close together if

it wants to send a 0 produces a low

frequency wave so the wave is really far

apart so those are the three main ways

that we send bits using computers let's

look an example of how a short message

is sent over a connection this

connection is purely symbolic

it could be just light it could be just

radio wave it could be a combination of

them in some way these two computers are

connected and they are able to set the

state of that connection to a 1 or a 0

so let's send the one that could either

mean a high frequency wave or a high

voltage but this computer sends the 1

and computer notices and says hey I see

a 1 then it sends a 0 it notices and

sees a zero changes it to 1 the computer

on the right notices and receives a 1

and then it sends a 0 and the computer

on the right receives a 0 perfect

we have a message that was reliably sent

from one computer to another what

happens though if we have three zeros in

a row in this case we can set the wire

to a one and the computer notices and

records a one now we set it to a zero

and then we set it to zero again and

then we set it to zero again since there

was no change in the wire the computer

didn't know to record any bit finally we

send that last one and the message

received is different from the message

sent this is a problem so to fix this we

introduce a clock with this clock both

computers can agree to send and record

bits at the same rate so let's say we're

gonna send a bit per second now one

second goes by and we set it to a one

another second goes by and the wire is

set to a zero another second and it's

still zero it records a new bit another

second goes by records a new bit and

lastly sets it to a one and we are able

to receive the full message now the

problem is one bit per second is

incredibly slow

luckily computers can move a lot faster

than one bit per second so if we want to

download a song or a video or a program

in a matter of seconds or minutes we

need to increase our bandwidth so

introducing bandwidth bandwidth is the

capacity of data transfer in a system

and it is measured by bitrate so you can

think of bandwidth as the speed of data

transfer in the network and it's

measured by bitrate bitrate is the

number of bits that a system can send in

one second so an example of low

bandwidth might be something like we

just saw one bit per second if we want a

really high bandwidth we got to increase

it up to five megabits per second and

that's actually pretty reasonable

several networks have at least five

megabits per second as a bitrate there's

one more important term when we're

talking about networks and sending data

and that is latency so latency is the

time it takes for a single bit to get

from sender to receiver now when it

comes to late and see we want low

latency if we have a low latency that is

a very fast connection now fiber optic

cable has the best latency because it's

using light and so it's traveling close

to the speed of light using a fiber

optic cable one bit can travel a full

kilometer in only five microseconds

with Ethernet on the other hand takes

about 300 microseconds to travel one

kilometer and we should note that

Ethernet connections are typically

shorter than one kilometer but should

the connection be one kilometer that

is how long a bit would take to travel

so to recap a network is simply a group

of two or more computers that are

somehow connected and they're typically

connected through routers and what do

these connections look like how do

computers actually send bits from one

computer to the other well one way is

electricity for example Ethernet another

way is light for example two fiber-optic

cables and lastly we can use radio and

this is what's being used in Wi-Fi and

cellular no matter the connection all

you're doing is sending bits and it can

be through radio waves it can be through

voltages it can be through lights but

that is what it boils down to is that

you are encoding the information you

want to send in bits sending it over the

network and then the zeros and ones will

be reconstructed to produce the original

data at the other end also to recap

three important terms we have bandwidth

and that is the capacity of data

transfer in a system and that is

measured by bitrate bitrate is the

number of bits that a system can send in

one second and that can range from bits

per second to kilobits per second

megabits per second even gigabits per

second and last we have latency and

latency is the time it takes for a bit

to get from a sender to the receiver and

that largely depends on the material

that is being sent through and so these

are the physical systems that the

internet is built upon this is the

physical hardware that is used to send

bits across the globe