Internet Hardware

Summary

This video script delves into the physical infrastructure of the internet, explaining how networks of connected computers are linked through routers. It highlights the scalability issue with direct connections and introduces routers as intermediaries. The script further explains how the internet is a vast network of routers, each connected to only a few others, and how internet service providers facilitate connections. It details the three primary methods of data transmission: electricity via Ethernet cables, light through fiber optic cables, and radio waves for Wi-Fi and cellular networks. The video also covers concepts of bandwidth, bit rate, and latency, emphasizing their importance in data transmission speed and efficiency.

Takeaways

• 🌐 The internet is a network that connects individual networks.
• 💻 A network is a group of two or more computer systems linked together.
• 🔗 Connecting multiple computers directly is not scalable for large networks.
• 🛂 Routers act as middlemen to efficiently connect devices within and between networks.
• 🌉 The internet is a massive network of routers, not a single large router.
• 🏠 Internet Service Providers (ISPs) provide routers for individual networks to connect to the internet.
• 🔢 Information is sent as digital bits (zeros and ones) across the network.
• 💡 Electricity, light, and radio waves are the three main methods used to transmit bits.
• 📡 Ethernet cables use electricity to transmit bits over medium distances.
• 🌊 Fiber optic cables use light to transmit bits over long distances, like undersea communication.
• 📶 Wi-Fi and cell towers use radio waves to transmit bits wirelessly over short distances.
• 🕒 A clock is used to synchronize the sending and receiving of bits to avoid data loss.
• 🚀 Bandwidth refers to the data transfer capacity, measured in bits per second.
• ⏱️ Latency is the time it takes for a bit to travel from sender to receiver, with fiber optic having the lowest latency.

Q & A

What is the internet?

The internet is a network that connects individual networks, allowing computers to communicate and share information.

What is a network?

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

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

It is impractical due to scalability issues; as the number of devices increases, it becomes unrealistic for each device to have a direct link to every other device.

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

A router is a networking device that forwards data between different networks. It simplifies connections by allowing multiple devices to connect to it, rather than to each other, and then handles the routing of data to the correct destination.

How does the internet handle the connection of many small networks?

The internet connects many small networks by using a vast network of interconnected routers, where each router is only connected to a few others, creating a complex web of connections.

What is an internet service provider and what role do they play?

An internet service provider (ISP) is a company that provides access to the internet. They supply the routers that individual networks connect to in order to join the internet.

How is digital information represented and sent across the network?

Digital information is represented as a series of zeros and ones, or binary code, which is 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., through Ethernet cables), light (e.g., through fiber optic cables), and radio waves (e.g., Wi-Fi and cellular signals).

How does electricity transmit data in Ethernet cables?

Electricity transmits data by representing ones with high voltage and zeros with low voltage, allowing the receiving computer to interpret the signal.

What are the advantages and disadvantages of fiber optic cables?

Advantages include the ability to transmit data over long distances, like under oceans. Disadvantages include the high cost and limited use to large-scale networks due to expense.

How does the use of radio waves for data transmission work?

Radio waves transmit data by encoding ones as high-frequency waves and zeros as low-frequency waves, allowing devices like Wi-Fi routers and cell towers to send bits through the air.

What is meant by bandwidth and how is it measured?

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

What is latency and why is it important?

Latency is the time it takes for a single bit to travel from sender to receiver. Low latency is desirable for fast connections, and it varies depending on the medium used for transmission.

Outlines

00:00

🌐 Understanding the Internet's Hardware

This paragraph introduces the concept of the internet's hardware, which refers to the physical systems that support the internet's functionality. It explains that the internet is a network of networks, connecting individual networks through a series of routers. The paragraph discusses the scalability issue of direct connections between computers and how routers act as middlemen to manage data transmission efficiently. It also touches on the role of internet service providers in providing access to the internet through these routers.

05:00

🚀 How Data is Transmitted Over the Internet

This section delves into the methods by which data is transmitted over the internet. It explains that data is represented in binary form (zeros and ones) before being sent across the network. The three primary methods of data transmission are identified as electricity (using Ethernet cables), light (using fiber optic cables), and radio waves (used in Wi-Fi and cellular networks). The pros and cons of each method are discussed, including the trade-offs between cost, distance, and speed. The paragraph also introduces the concept of a clock to synchronize data transmission and avoid errors due to consecutive bits of the same value.

10:02

📶 The Role of Bandwidth and Latency in Internet Communication

The final paragraph focuses on the importance of bandwidth and latency in internet communication. Bandwidth is described as the capacity for data transfer, measured in bit rate, which indicates the number of bits that can be sent per second. The paragraph contrasts low bandwidth with high bandwidth, giving examples of typical bit rates for different types of networks. Latency, defined as the time taken for a bit to travel from sender to receiver, is also discussed, with fiber optic cables highlighted for their low latency due to the speed of light. The paragraph concludes by summarizing the physical systems that underpin the internet, emphasizing the use of electricity, light, and radio waves to transmit bits globally.

Keywords

💡Internet

The Internet is a global network that connects individual networks, allowing devices to communicate with one another. In the video, it is described as a network of routers that facilitate the exchange of information across vast distances. It is the core infrastructure that enables the sharing of digital content and communication worldwide.

💡Network

A network refers to a group of two or more computer systems that are linked together to share resources and exchange information. The video script explains that networks can be as simple as two computers connected by a single link or as complex as the Internet, which connects millions of devices through routers.

💡Router

A router is a networking device that forwards data packets between computer networks. It acts as a middleman, connecting individual devices or networks to a larger network and directing data to its intended destination. The video emphasizes the importance of routers in scaling networks beyond direct connections between every device.

💡Bandwidth

Bandwidth is the capacity of data transfer in a system, measured by bit rate. It represents the speed at which data can be transmitted over a network. The video script mentions that increasing bandwidth allows for faster data transfer, which is crucial for downloading large files or streaming high-quality media.

💡Bit Rate

Bit rate is the number of bits that a system can send in one second, and it is a measure of the data transfer speed. The video script uses bit rate to illustrate the difference between slow and fast networks, with higher bit rates indicating faster networks capable of handling more data in less time.

💡Latency

Latency is the time it takes for a single bit to travel from the sender to the receiver. The video script explains that low latency is desirable for fast connections, with fiber optic cables offering the best latency due to the speed of light transmission, making them ideal for long-distance data transfer.

💡Electricity

Electricity is one of the three methods used to send information across the Internet, as mentioned in the video. It is used in Ethernet cables, which send data through copper wires by representing bits as different voltage levels. The video script points out that while electricity is a cost-effective method, it is limited in the distance it can cover before the signal degrades.

💡Light

Light is used in Fiber Optic Cables to transmit data over long distances, as explained in the video. It is a more expensive method compared to electricity but offers the advantage of covering vast distances without significant signal loss. The video script uses light to illustrate how data can be sent across continents and under oceans.

💡Radio Waves

Radio waves are used for wireless data transmission, as discussed in the video script. They are the technology behind Wi-Fi and cellular networks, allowing devices to send and receive data without physical connections. The video notes that while radio waves offer convenience and mobility, they are limited by short transmission ranges and can be affected by interference.

💡Encoding

Encoding in the context of the video refers to the process of representing information as a series of zeros and ones, or binary code, which is how data is transmitted over the Internet. The video script explains that whether the data is sent as electricity, light, or radio waves, it is first encoded into bits to be sent across the network.

💡Internet Service Provider (ISP)

An Internet Service Provider is a company that provides access to the Internet. The video script mentions ISPs like Comcast and AT&T, which offer the necessary routers and connections for individual networks to join the global Internet. ISPs play a critical role in providing the infrastructure that connects homes, businesses, and other organizations to the worldwide network of 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.

Routers act as middlemen to forward requests in a network.

The internet is a massive network of routers, not a single entity.

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

Data transmission involves encoding information into zeros and ones.

Electricity, light, and radio are the three main methods to send information.

Ethernet cables use electricity to represent bits as high or low voltages.

Fiber optic cables use light to transmit bits over long distances.

Radio waves are used in Wi-Fi and cellular networks for short-range communication.

A clock is introduced to synchronize bit transmission and avoid data loss.

Bandwidth is the capacity of data transfer, measured by bit rate.

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

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

Ethernet connections are typically shorter than 1 km due to latency concerns.

The physical systems of the internet include hardware for sending bits globally.

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 there

exist 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 computer in a

separate Network now this solution is

good for a small number of simple

networks but the problem is when 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 a 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 going

to use the power of digital information

we're we're going to 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 at a symbolic level the

internet is really just a way to get

zeros and ones from point A to point B

but at 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 with electricity is that

it's cheap and the cons are 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

so the physical way that we send bits

using electricity is we just set the

wire to be a high voltage to represent a

one and we set the wire to have a low

voltage to represent a 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 fiberoptic cables is they

can travel very long distances it can

travel across the floor of the ocean the

cons is that it's 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 one 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 one it just

produces a high frequency wave so the

wave is very tight and close together if

it wants to send to zero it 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 at an example of

how a short message is sent over a

connection and 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 one or a zero so let's send the one

that could either mean a high frequency

wave or a high voltage but this computer

sends the one and the computer notices

and says hey I see a one then it sends a

zero it notices and sees a zero changes

it to one the computer on the right

notices and receives a one and then it

sends a zero and the computer on the

right receives a zero 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 Y 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 going to 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 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 bit rate so you can think of

bandwidth as the speed of data transfer

in the network and it's measured by bit

rate bit rate 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 5

megabits per second and that's actually

pretty reasonable several networks have

at least 5 megabits per second as a bit

rate 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 latency 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 5

micros with ethernet on the other hand

takes about 300 microseconds to travel 1

km and we should note that ethernet

connections are typically shorter than 1

km but should the connection be 1

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 the 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're 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 bit rate bit rate 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 lastly 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 it's 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