Internet Hardware
Summary
TLDRThis 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
🌐 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.
🚀 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.
📶 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.
Mindmap
Keywords
💡Internet
💡Network
💡Router
💡Bandwidth
💡Bit Rate
💡Latency
💡Electricity
💡Light
💡Radio Waves
💡Encoding
💡Internet Service Provider (ISP)
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
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