Limitations of the Internet

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Google의 강좌에서

Technical Support Fundamentals

12533개의 평가

Google

Technical Support Fundamentals

12533개의 평가

Specialization Google IT Support Professional Certificate에서 5의 강좌 1

This course is the first of a series that aims to prepare you for a role as an entry-level IT Support Specialist. In this course, you’ll be introduced to the world of Information Technology, or IT. You’ll learn about the different facets of Information Technology, like computer hardware, the Internet, computer software, troubleshooting, and customer service. We’ll go through what a technical interview could look like, and provide tips on how to best prepare for one. This course covers a wide variety of topics in IT that are designed to give you an overview of what’s to come in this certificate program. By the end of this course, you’ll be able to: ● understand how the binary system works. ● assemble a computer from scratch. ● choose and install an operating system on a computer. ● understand what the Internet is, how it works, and the impact it has in the modern world. ● learn how applications are created and how they work under the hood of a computer. ● utilize common problem-solving methodologies and soft skills in an Information Technology setting.

수업에서

Networking

In the fourth week of this course, we'll learn about computer networking. We'll explore the history of the Internet and what "The Web" actually is. We'll also discuss topics like Internet privacy, security, and what the future of the Internet may look like. You'll also understand why the Internet has limitations even today. By the end of this module, you will know how the Internet works and recognize both the positive and negative impacts the Internet has had on the world.

History of the Internet4:10

Limitations of the Internet3:51

강사 만나기

Google

We've mentioned IP addresses a lot in

this course but we haven't actually gone into detail about them.

They are actually different versions of IP addresses.

The current Protocol, Internet Protocol version four or IPv4

is an address that consists of 32 bits separated into four groups.

Remember, 42 bits is four bytes and one byte can be stored

up to 256 values from 0 to 255.

So IPv4 addresses, can be something like 73.55.242.3.

Even though it might seem like a lot of possible IPv4 addresses,

there are less than 4.3 billion IPv4 addresses.

There are way more than 4.3 billion websites out on the web today.

Some IPv4 addresses are even reserved for special purposes.

So, the number of usable IP addresses is even less.

A device that wants to connect to the internet,

needs to have an IP address but

devices around the world have already exceeded those numbers.

So, where have we been getting IP addresses?

IP addresses have been able to keep up with the amount of devices in the world,

thanks to IPv6 or Internet Protocol version six addresses.

IPv6 addresses consist of a 128 bits,

four times the amount that IPv4 uses.

Which means way more devices can have IP addresses.

The adoption of IPv6 addresses has been slow but steady.

Eventually, you will start seeing more and more IPv6 addresses in the wild.

An example IPv4 for address can be something like 172.14.24.1.

But an IPv6 address can be something like what you see here,

quite a bit of a difference, don't you think?

Here's an analogy for how big this difference is between IPv4 and IPv6.

With IPv6 there are 2 to the 128 power possible IP addresses,

2 to the 128 power is an insanely huge number.

So huge, that scientists had trouble describing with words just how big this number is.

So, here's an analogy.

Think of a grain of sand,

if you scoop up a handful,

do you know how many grains you have in your hand?

Probably a lot but that is not even close to the number we are talking about.

Now, take all the grains of sand in the entire world,

assuming there are roughly 7 and a half

times 10 to the 18th power grains of sand in the world.

That still would not be enough IPv6 addresses.

Now, let us take all the sand from multiple earths,

now you are close to what that number would be.

It is a crazy large number.

Just know that we will not be running out of IPv6 addresses anytime soon.

Another mitigation tool that we have been able to use

is NAT or Network Address Translation.

This lets organizations use

one public IP address and many private IP addresses within the network.

Think of NAT like a receptionist at a company.

You know what number to dial to get to the company and once you reach the receptionist,

he can transfer your call to one of the private numbers inside the company.

Now, instead of companies using hundreds of public IP addresses,

they can just use one IP address.

Remember the routers we talked about earlier?

One task you might need to perform when you are an I.T.

support specialist, is to configure NAT on a router to

facilitate communication between your company's network and the outside world.

There are lots of other limitations that we have had to deal with.

You'll learn more about them in the networking course.

For now, you should have a general understanding of why IPv4 is

so limiting for us today and how IPv6 helped solve that.

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