Week 4: Networking

Hi, my name is Victor Escobedo and
I’m a corporate operations engineer. I’m excited to spend the next few
lessons with you before my colleague and friend Jeon takes the reins and wraps up
the rest of the lessons on the internet. Before we dive in though, I’d like to
tell you a little bit about myself. My passion for IT began way back
when I was nine years old, and my dad brought home our first computer. He was a mechanical engineer and started using the computer to
help him with his CAD work. This was the first time I
was exposed to computers and later realized you can install new
software on it, including computer games. As I tinkered with the computer, surely
to my dad’s dismay, I became more and more interested in how it worked and
eventually started to open up the case and peek inside. I found pieces that could be removed and
even some that shouldn’t, learning through trial and
error along the way. I couldn’t really explain what it was but I just found the mechanics of how it
all worked together so fascinating. Looking back, these were
the seeds that inspired my career. But, you see where I grew up,
going to college and pursuing a career wasn’t exactly
talked about or heavily encouraged. I’m a first generation Mexican American,
and there weren’t a lot of people I
knew pursuing a career in tech. My friends and family were mostly
worried about graduating high school and making sure they had jobs,
not really thinking about careers. My school didn’t have the resources
to offer many technical classes and even though my father was working
in mechanical engineering, computers were a tool to him like a mill,
ruler, or a hammer. My parents encouraged me to work hard and
pursue computers but they couldn’t really give advice
about college or a career in tech to no real fault of their own, they
just didn’t have the necessary experience. When I decided to go to college,
I decided to try my hand at computer science since it
could feed my curiosity for how computers worked at
a more fundamental level. I realized that having this foundational
knowledge really allowed me to understand some of the higher level concepts that
were important in a career in tech. So while in school, I took on my
first IT job for local small company. I’ve been working in IT now for 12 years, with the last 7 years
being here at Google. I now work on managing deployment of large
internal IT projects for the company. Applying the knowledge I picked up over
the years in my initial IT helpdesk roles to make sure that I understand
how I’m impacting our users and various support teams. Now that you know a little bit about me,
let’s dig into the internet. The internet made it possible for us to
connect with almost anyone in the world. Before the internet,
you had to use paper maps and write down step by step directions
to get where you wanted to go. If you wanted to see what your friends
were up to, you’d have to call them, actually talk to them. If you wanted to learn something new,
you had to go to a library and hope they have a book on
the subject you wanted to learn. People didn’t really discover new
restaurants unless they heard about it from someone else or it was advertised. There was no Yelp or other website that
rates restaurants like we have today. For some of us, life without the internet
seems unimaginable, we get it, it’s become an integral part of our lives. In the next few lessons, you’ll be
learning about what the internet is, how it came to be, and how it has impacted
us both in negative and positive ways.

What is networking?

Networking is the practice of connecting computers and devices together so that they can communicate with each other. Networks can be small, such as a home network, or large, such as the Internet.

Components of a network

The basic components of a network are:

• Devices: The computers, printers, routers, switches, and other devices that are connected to the network.
• Media: The physical cables or wireless signals that carry data between the devices on the network.
• Protocols: The rules and standards that govern how the devices on the network communicate with each other.

Types of networks

There are many different types of networks, but some of the most common ones include:

• Local area networks (LANs): These are small networks that are confined to a single location, such as a home or office.
• Wide area networks (WANs): These are large networks that connect multiple LANs over long distances.
• Metropolitan area networks (MANs): These are networks that connect LANs within a city or metropolitan area.
• Virtual private networks (VPNs): These are secure networks that are created over the public Internet.

Networking terminology

Here are some of the most important networking terms to know:

• IP address: A unique identifier that is assigned to each device on a network.
• MAC address: A unique identifier that is assigned to each network interface card (NIC).
• Router: A device that forwards data packets between different networks.
• Switch: A device that connects devices on the same network.
• Hub: A device that connects multiple devices on the same network, but does not filter or forward data packets.
• Gateway: A device that connects a network to another network, such as the Internet.
• Protocol: A set of rules that govern how data is exchanged between devices on a network.

Networking concepts

Here are some of the most important networking concepts to understand:

• Packet: A unit of data that is sent over a network.
• Transmission control protocol (TCP): A reliable protocol that guarantees the delivery of data packets.
• User datagram protocol (UDP): An unreliable protocol that does not guarantee the delivery of data packets.
• Ethernet: A common networking technology that uses copper cables to transmit data.
• Wi-Fi: A common networking technology that uses radio waves to transmit data.
• Firewall: A device that protects a network from unauthorized access.
• Intrusion detection system (IDS): A device that monitors a network for suspicious activity.
• Intrusion prevention system (IPS): A device that blocks suspicious activity on a network.

Networking applications

Networking is used in a wide variety of applications, including:

• File sharing
• Email
• Internet browsing
• Voice over IP (VoIP)
• Video conferencing
• Remote access
• Data backup
• Network security

Learning networking

There are many ways to learn about networking. You can take networking courses, read networking books, or watch networking tutorials. You can also get hands-on experience by setting up and configuring a home network.

Conclusion

Networking is a complex and ever-evolving field, but it is essential for anyone who wants to work in IT. By understanding the basics of networking, you will be well on your way to a successful career in IT.

A(n) ______ is an interconnection of computers.

network

You got it! You can connect many computers together to form a network.

In an IT field, managing, building, and designing networks is known as ______.

networking

Great job! The management and building of networks is known as networking.

When most people think
of the Internet, they think of a
magical cloud that lets you access your
favorite websites, shop online, and you assumingly endless
stream of cat pictures, but there isn’t any
magic involved. There’s no mysterious entity that grants us a cat
picture on-demand. The Internet is just
an interconnection of computers around the world, like a giant spider web that
brings all of us together. We call the interconnection
of computers a network. Computers in a network can talk to each other and
send data to one another. You can create a simple network
with just two computers. In fact, you might already
have your own network at home connecting all
of your home devices. Let’s think on a bigger scale. What about the computers at
your school or workplace? Are they in a network?
They sure are. All of the computers there are linked together
in a network. Can we link your home, school, and workplace’s
networks together? We absolutely can. Your workplace connects
to a bigger network, and that network connects to an even bigger network
and on and on. Eventually, you’ve got billions of computers
that are interconnected, making up what we
call the Internet. You, like most people, probably access the
Internet through a browser like Mozilla Firefox, Google Chrome, Microsoft
Edge, or something else. This is done through
the World Wide Web. But don’t make the
mistake of thinking the Internet is the
World Wide Web. The Internet is the
physical connection of computers and wires
around the world. The web is the information
on the Internet. We use it to access
the Internet through a link like www.google.com. The World Wide Web isn’t the only way we can
access the Internet. Your email, chat, and file-sharing programs are also ways you can access
the Internet. In the IT field, managing, building, and designing networks
is known as networking. Networking is a super important
and large field in IT. There are specialized jobs,
college degree programs, and tons of literature dedicated
entirely to networking. If you work in the IT field, it’s super critical that you understand the fundamentals
of networking. The Internet is composed of a massive network
of satellites, cellular networks, and physical cables buried
underneath the ground. We don’t actually connect
to the Internet directly. Instead, computers called servers connect directly
to the Internet. Servers store the
websites that we use, like Wikipedia, Google,
Reddit, and BBC. These websites serve content. The machines that we use, like our mobile phones, laptops, video game consoles, and more are called clients. Clients request the
content like pictures, websites from the servers. Clients don’t connect
directly to the Internet. Instead, they
connect to a network run by an Internet
service provider or ISP, like CenturyLink, Level 3, Comcast, Telefonica
and things like that. ISPs have already
built networks and run all the unnecessary physical
cabling that connects millions of computers
together in one network. They also connect to other
networks and other ISPs. These other networks connect
to the networks of Google, Reddit, universities, basically all the other
networks in the world. Together, they form
one giant network of computers called
the Internet. But how do the clients know
how to get to servers? Well, how would you send
a letter to someone? You’d put your address on
the letter and send it to the address of the person you’re sending the letter to. Computers have addresses
just like houses. Computers on a network have an identifier called
an IP address. An IP address is
composed of digits and numbers like 100.1.4.3. When we want to
access a website, we’re actually going
to their IP address, like 172.217.6.46. Devices that can connect
to a network have another unique identifier
called a MAC address. MAC addresses are generally permanent and hard-coded
onto a device. A sample MAC address can
be something like this. When you send or receive
data through a network, you need to have both an
IP and a MAC address. You might be wondering
why we need to have two different numbers
to identify something. That’s a good
question. Think again of the letter analogy
we use before. An IP address is
your house address, while the MAC address is the name of this
recipient of the letter. You want to make sure
your letter gets to the right location and
to the right person. A more simplified example of the letter delivery
would go like this. I’m in New York city and I got a letter that I want to
send to a friend, May. May’s halfway across
the world in Tokyo. Our letter, we’ll
go through lots of places before it reaches her. I put her name and
address on there and I also put my name
and address on there too. When I drop my letter
off at the post office, the mail person looks at it. He thinks, I don’t know how
to get to Tokyo from here, but there’s a truck
that’s headed to Texas. He puts my letter in that truck at the post office in Texas. A mail person looks at
the letter and says, I don’t know how to get
to Tokyo from here, but we have a truck
going to San Francisco. She puts my letter
in that truck. At the post office
in San Francisco, yet another mail person
looks at my letter. He says, there’s
a plane headed to Tokyo and puts the
letter on that plane. When it finally reaches Tokyo, the postman there says, I know where May lives and
delivers the letter to her. Obviously, there are
many more nuance to mail delivery than
what I described, but this process
is similar to how information gets routed
across the Internet. One thing to call out
is that data that’s sent through a network
is sent through packets. There’s little bits of data and you guessed it,
ones and zeros. It doesn’t matter
if it’s pictures, email, music, or text. When we move data
through the network, we break them down into packets. When a packet gets
to its destination, it will rearrange
itself back in order. Think of a packet like a letter. Let’s actually look at
this process again, but this time we’ll use IP
addresses and MAC addresses. Natalie has a computer
with IP address 113.8.81.2 and she wants to go to google.com and
search for pictures of cats. Before she does that,
her computer has to send a packet to ask google.com if it can access their website. Our packet knows google.com’s IP address is 172.217.6.46, but it doesn’t know how
to get there just yet. The packet travels
from one place to another at each
destination where it asks, hey, do you know
where google.com is? Eventually it’ll be routed to another destination that can get the packet closer and
closer to google.com. Once it reaches a
destination that can deliver the packet to
aserver@google.com, Google will send
Natalie a packet saying she can access an unlimited
number of cat pictures.

Networking hardware is the physical components that make up a computer network. This includes devices such as routers, switches, hubs, and bridges. Networking hardware allows computers and other devices to communicate with each other and share resources.

Types of networking hardware:

• Routers: A router is a device that connects two or more networks together. It is responsible for routing traffic between the networks. Routers use network protocols to determine the best path for data to travel.
• Switches: A switch is a device that connects multiple devices on the same network together. It acts as a traffic manager, directing data to the correct device. Switches are typically used to connect computers, printers, and other devices to a network.
• Hubs: A hub is a simple networking device that connects multiple devices together. It acts as a repeater, broadcasting all data packets to all connected devices. Hubs are no longer commonly used, as they can cause network congestion.
• Bridges: A bridge is a device that connects two similar networks together. It acts as a filter, only forwarding data packets to the intended network. Bridges are often used to connect Ethernet networks together.

Other types of networking hardware include:

• Modems: A modem is a device that converts digital signals to analog signals so that they can be transmitted over a telephone line. Modems are used to connect computers to the internet.
• Firewalls: A firewall is a security device that monitors and controls incoming and outgoing network traffic. Firewalls are used to protect networks from unauthorized access and malicious attacks.
• Wireless access points (WAPs): A WAP is a device that allows devices to connect to a wireless network. WAPs are typically used in homes and businesses to provide wireless internet access.

Networking hardware is essential for building and maintaining computer networks. By understanding the different types of networking hardware and their functions, you can create and troubleshoot networks more effectively.

Now that we understand what networks are. Let’s talk about how they’re connected. There are a lot of ways you can
connect computers to a network, we’ll only cover a few of
the major ones in this course. First, there’s an ethernet cable which
lets you physically connect to the network through a cable. On the back of the desktop we
worked in the previous lessons, there’s a network ports that you
plug your ethernet cable into. Another way to connect to
a network is through Wi-Fi, which is wireless networking. Most modern computing systems have
wireless capabilities like mobile phones, smart televisions and laptops. We connect to wireless networks
through radios and antennas. The last method will go over uses fiber
optic cables to connect to a network. This is the most expensive method since
fiber optic cables allow greater speeds than all the other methods, fiber optic
gets its name because the cables contain glass fibers that move data through
light instead of electricity. This means that we send ones and
zeros through a beam of light instead of an electrical current
through a copper wire. How cool is that? But our cables have to
connect to something. We don’t just have millions
of cables going in and out of computers to connect them together. Instead, computers connect to a few
different devices that help organize our network together. The first device that your
computer connects to is a router. A router connects lots of
different devices together and helps route network traffic,
let’s say we have four computers, A, B, C and D connected together
through a router in the same network. You want to send a file from
computer A to computer B. A packets go through the router and the router utilizes network protocols to
help determine where to send the packet. So now our packet gets routed from
computer A to computer B, sweet. What if we wanted to send a packet
to a computer not in our network? What if we wanted to send a packet
to our friend Alejandro’s computer. Alejandro is on a different
network altogether. Fortunately, our router knows how to
handle that to the packet will get routed outside our network to our ISPS
network using networking protocols, it’s able to figure out where
Alejandro’s computer is. During this process, our packet is
traveling across many different routers, switches and hubs, switches and hubs are
also devices that help our data travel. Think of switches like
mail rooms in a building, routers get our letters to the building, but once we’re inside we use the mail room
to figure out where to send a letter. Hubs are like company memos, they
don’t know who to send the memo to, so they send it to everyone. Working with network devices is important
to understand because it’s likely that one day you’ll have users reporting
problems accessing the Internet, you’ll want to investigate your way up
the network stack, a technology stack. In this case a network stack
is just a set of hardware or software that provides
the infrastructure for a computer. So the network stack is all the components
that makes up computer networking. You might need to investigate
the network stack in your job. You’d start with making sure the end
user computers are working properly. Then you turn your attention to
other possible points of failure, like the cabling, switches and routers
that work together to access the Internet.

TCP/IP, or Transmission Control Protocol/Internet Protocol, is a suite of protocols that are used to connect devices to the internet. It is the most widely used protocol suite in the world.

TCP/IP is made up of four layers:

• Application layer: This layer is responsible for providing network services to applications, such as web browsing, email, and file transfer.
• Transport layer: This layer is responsible for providing reliable end-to-end communication between applications. The two main transport protocols are TCP and UDP. TCP provides reliable delivery of data, while UDP does not.
• Internet layer: This layer is responsible for routing data packets between devices on different networks. The main internet protocol is IP. IP is responsible for assigning IP addresses to devices and routing packets to the correct destination.
• Link layer: This layer is responsible for transmitting data packets over a physical medium, such as an Ethernet cable or Wi-Fi.

TCP and IP are the two most important protocols in the TCP/IP suite. TCP is responsible for ensuring that data is delivered reliably from one computer to another. IP is responsible for routing data packets to the correct destination.

How TCP/IP works:

When you send data over the internet, your computer breaks it down into packets. Each packet contains the destination IP address, the source IP address, and the data itself.

The packets are then routed through the internet by routers and switches. Routers use routing tables to determine the best path for the packets to take.

When the packets reach the destination computer, they are reassembled into the original data. TCP ensures that the packets are delivered in the correct order and that none of them are lost.

TCP/IP is a complex protocol suite, but it is essential for the operation of the internet. By understanding the basics of TCP/IP, you can better understand how the internet works and how to troubleshoot network problems.

Here are some examples of how TCP/IP is used in everyday life:

• When you browse the web, TCP/IP is used to transfer data between your computer and the web server.
• When you send an email, TCP/IP is used to transfer the email message between your computer and the email server.
• When you download a file from the internet, TCP/IP is used to transfer the file from the web server to your computer.
• When you stream a video from the internet, TCP/IP is used to transfer the video data from the video server to your computer.

TCP/IP is a powerful and versatile protocol suite that is used to connect devices to the internet and other networks. It is essential for the operation of the modern world.

There are lots and lots of
network protocols used, and they’re all
necessary to help us get our packets in
the right place. Think of network
protocols like a set of rules for how we transfer
data in a network. Imagine if you sent a letter
to your friend Sasha, who lives in California, but your post office
sends it out to another Sasha who
lives out in New York. That would hopefully
never happen since the post office has rules that they follow to make sure your letter is sent to
the correct address. Our networking protocols
do the same thing. There are rules that make sure our packets are
routed efficiently, aren’t corrupted, are secure, go to the right machine, and are named appropriately. You get the idea. We’ll cover specific network
protocols later on. But there are two protocols
that you need to know. The Transmission
Control Protocol and the Internet Protocol, or TCPIP for short, which had become the predominant protocols of the Internet. The Internet Protocol, or IP, is responsible for delivering our packets to the
right computers. Remember those addresses that computers use to find
something on a network? They’re called IP addresses or Internet Protocol Addresses. The Internet Protocol helps
us route information. The Transmission Control
Protocol, or TCP, is a protocol that handles reliable delivery of information from one network to another. This protocol was an important
part of the creation of the internet since
it led us share information with
other computers. For now, you’ve got a high level
understanding of how the Internet works with TCP, IP.

The web is a system of interconnected hypertext documents that are accessed via the internet. It is the most popular way to access information online.

The web is based on the Hypertext Transfer Protocol (HTTP), which is a communication protocol that allows web servers to send web pages to web browsers. Web pages are written in HTML, which is a markup language that is used to structure and format web content.

To access a website, you type its URL into a web browser. The URL stands for Uniform Resource Locator and is the web address of the website. The URL is made up of three parts:

• The protocol, which is usually http or https
• The domain name, which is the name of the website
• The top-level domain, which is the ending of the domain name, such as .com or .org

When you type a URL into a web browser, the browser sends a request to the web server for the web page. The web server then sends the web page to the browser. The browser then displays the web page to you.

The web in IT

The web is an important part of IT. It is used to deliver a wide range of IT services, such as:

• Web applications: Web applications are software applications that are delivered over the web. Examples of web applications include email, web browsers, and online banking.
• Web APIs: Web APIs are programming interfaces that allow developers to access data and services from other websites. Examples of web APIs include the Google Maps API and the Twitter API.
• Web hosting: Web hosting is the service of providing space on a web server for websites.
• Content delivery networks (CDNs): CDNs are networks of servers that are distributed around the world. They are used to deliver content to users in a fast and reliable way.

Web development

Web development is the process of creating and maintaining websites. Web developers use a variety of programming languages and tools to create websites. Some of the most popular web development languages and tools include:

• HTML, CSS, and JavaScript: These are the three core web development technologies. HTML is used to structure and format web content, CSS is used to style web content, and JavaScript is used to add interactivity to web content.
• PHP, Python, and Ruby on Rails: These are three popular server-side web development languages. They are used to create web applications that are hosted on web servers.
• React, Angular, and Vue.js: These are three popular JavaScript frameworks that are used to create web applications.

Conclusion

The web is an important part of IT and web development is a growing field. If you are interested in a career in IT, consider learning about web development.

Lots of different ways to use
the internet, we all know that. But I want to cover one of the more
prevalent ways that people access the internet, through the web. All websites can be
accessed through the web. Websites are basically text documents
that we format with HTML or HyperText Markup Language. It’s a coding language
used by web browsers. Web pages are generally made
up of very basic components. They contain multimedia content like text,
images, audio and video. When you want to navigate to a website, you would type in URL like,
www.reddit.com. A URL which stands for Uniform Resource Locator is just a web
address similar to a home address. Notice the www in the URL,
it stands for World Wide Web. The second portion, reddit.com is
something we call a domain name. Anyone can register a domain name,
it’s just our website name. Once a name is taken it will
be registered to ICANN, the Internet Corporation for
Assigned Names and Numbers. Once a domain name is registered with,
ICANN, no one else can take that name
unless it becomes available again. The last part of the URL,
in this case is dot com. But you can also use different domain
endings like reddit.net or reddit.org. The different domain name
endings are standards for what type of website it might be. So a domain that ends in .edu is mainly
used for educational institutions. Remember how computers use IP
addresses to find another computer. Well, you can do the same if you wanted
to find a computer on the internet. Let’s go ahead and type 172.217.6.46
into a web browser and hit enter. Wait a minute, what happened? How come we’re at Google’s homepage? It turns out the IP address
172.217.6.46 maps to Google’s homepage through a critical web
protocol Domain Name System or DNS. DNS acts like our internet directory. And let’s just use human readable
way words to map to an IP address. The computer doesn’t
know what Google.com is. It only knows how to get
to an IP address with DNS. It’s able to map google’s
IP address with Google.com. Every time you go on a website, your
computer is performing a DNS look up to find the IP address of
the website name you typed in. This trick can be a good first step in
diagnosing certain kinds of DNS issues. So if you’re able to access
a website by its IP address but not its human readable domain name,
then there’s a good bet that there’s probably a problem somewhere in the DNS
configuration your network is using. Understanding IP addresses can come in
handy in all sorts of other situations you might encounter as an IT
support specialist. The source of internet requests
are usually identified by IP addresses in server logs. Many pieces of IT infrastructure
need to have some kind of IP address configuration
applied to them in order to work. DNS is a huge system and
we’ll be discussing more about it later. Now that you understand the basics
of how the internet works. I’ll sign off for now, and leave you in
the very capable hands of my friend and colleague Jeone Spicuzza. I’ll see you again in course to the bits
and bytes of computer networking. But in the next lessons, Jeone is going to talk about
the incredible boom of the internet age.

[MUSIC] My first IT job I was essentially
a glorified spam filter. They hired me part time to go
through the spam folder and then find anything that got mislabeled the
spam and forward it to people’s inboxes. So I did that for about a week and then I
was like this is insane, there is no way that huge companies are paying people to
sit in the back of the room and do this. So I started installing at the time, I was like spam assassin is
like open source mail filter. Yeah, and then I basically like automated
that away and I told my boss about it and I was like hey this is like
we don’t need this anymore, I don’t need to do that anymore. So then I started doing other things and I’m like I would create new accounts
that would delete all accounts. And I kind of just did that. I grew into eventually becoming
like the full time sys admin for for the company there. When I graduated I started looking at
other large companies that I might be excited to work for. So Google was one of them and
I threw my resume together and I sent it over for
one of the IT jobs that they had here and I didn’t really think
I was going to get it. I was literally in the means of
moving to Seattle when they told me like can you start in four weeks? So I had to figure it out. I had four weeks to change my plans
entirely and I started here and I learned like what IT really
looked like in a huge environment.

History of the Internet in IT

The Internet has become an essential part of our lives, both personally and professionally. It is used for everything from communication and entertainment to education and business. But how did the Internet come to be?

The history of the Internet can be traced back to the 1950s, when the US Department of Defense created a network called ARPANET (Advanced Research Projects Agency Network). ARPANET was designed to connect computers at different universities and research institutions so that scientists could share data and resources.

In the 1970s, two computer scientists named Vint Cerf and Bob Kahn developed a set of protocols called TCP/IP (Transmission Control Protocol/Internet Protocol). TCP/IP is the set of rules that computers use to communicate with each other over the Internet.

In the 1980s, ARPANET was opened up to commercial use, and the Internet began to grow rapidly. In the 1990s, the World Wide Web was invented, which made it possible to display information in web pages. The World Wide Web made the Internet even more popular, and it is now used by billions of people around the world.

The Internet has had a profound impact on the IT field. It has made it possible for IT professionals to collaborate with each other and share information more easily. It has also created new opportunities for IT professionals, such as web development and network security.

Here is a more detailed timeline of the history of the Internet:

• 1957: The Soviet Union launches Sputnik, the first artificial satellite. This event spurs the US government to invest heavily in research and development, including computer networking.
• 1962: J.C.R. Licklider publishes a paper titled “A Galactic Network,” which outlines his vision for a global computer network.
• 1969: ARPANET is launched, connecting four universities in the United States.
• 1971: Ray Tomlinson invents email.
• 1973: Vint Cerf and Bob Kahn publish a paper describing TCP/IP.
• 1983: The Domain Name System (DNS) is introduced.
• 1985: The National Science Foundation (NSF) creates NSFNET, a high-speed network that connects universities and research institutions.
• 1989: Tim Berners-Lee invents the World Wide Web.
• 1991: The World Wide Web is made available to the public.
• 1993: Mosaic, the first popular web browser, is released.
• 1995: Netscape Navigator, another popular web browser, is released.
• 1998: Google is founded.
• 2001: Wikipedia is launched.
• 2004: Facebook is launched.
• 2005: YouTube is launched.
• 2006: Twitter is launched.

The Internet continues to evolve today. New technologies and applications are being developed all the time. The Internet is a powerful tool that has changed the world in many ways. It is essential for IT professionals to understand the history of the Internet and how it works.

Impact of the Internet on the IT field

The Internet has had a profound impact on the IT field. It has made it possible for IT professionals to collaborate with each other and share information more easily. It has also created new opportunities for IT professionals, such as web development and network security.

Here are some specific examples of how the Internet has impacted the IT field:

• Collaboration: The Internet makes it easy for IT professionals to collaborate with each other, regardless of where they are located. This can be done through email, instant messaging, video conferencing, and other online tools.
• Information sharing: The Internet is a vast source of information for IT professionals. They can access information on a variety of topics, such as new technologies, troubleshooting problems, and best practices.
• New opportunities: The Internet has created new opportunities for IT professionals, such as web development, network security, and cloud computing.

The Internet is an essential tool for IT professionals. It allows them to stay up-to-date on the latest technologies, collaborate with each other, and find new opportunities.

You’ve learned what the Internet is and a little bit
about how it works. Now, we’re going to take a step back and learn why
it was created. But before we do that, I’d like to introduce myself. My name is Gian Picasa and I’m a Program Manager in
Android Security. I help protect Android’s two billion plus
users by managing new security
features for each of Android’s deserts or
versions of Android. I’ve always loved
technology and I worked in IT since I was 16 and
throughout university, I would fill my past time
reading about new tech and building servers from old computer parts
in my basement. My earliest memory of working on tech is waiting for my
parents to go to sleep so I could quietly dial up the Internet while the
phone was free and just browse websites all night long and read about
random tech things. My first jobs were as a one-person IT crew at three
non-profit organizations. It was both stressful and really exciting to be responsible
for everything, from configuring and
administrating backup servers to just showing new
employees how to access email and use
their computers. I’m really excited
to be here with you. I was never a really
great test taker and my grades reflected that. But I knew with hard
work and perseverance, I could build a great career
in IT and so can you. Let’s get started and dig in
a bit more on the Internet. The Internet has become an
essential part of our lives. Our bank accounts,
entertainment, news and education are
all on the Internet. It’s important to
learn why that is, since some of the
original designs of the Internet have reached
their limitations. As an IT support specialist, you should understand
what the future of the Internet holds and why. Let’s go back in time to the
1950s where it all started. Remember, back then computers
were huge and bulky. If you’re a programmer, you needed to directly
interact with these massive
computers that would get real old real fast, especially if you had
several people who wanted to use the only computing
resource available. The late 1960s,
the US government spun up a project called DARPA. It went on to create
the earliest version of the Internet that we’ve seen
today with the ARPANET. Eventually, computer
programmers were able to share a single computing resource by being able to remotely
access the computer. But there were still
a big problem. Networks couldn’t
talk to each other. It wasn’t until the
1970s that we had a critical breakthrough in computer networking
that fix this problem. It was thanks to
computer scientists, Vinton Cerf and Bob Kahn who
created the method we call the Transmission
Control Protocol and the Internet
Protocol, or TCP/IP. First, only a handful of
computers in universities, governments and businesses
adopt TCP/IP, then hundreds. Then in the span of 50 years,
billions of computers. TCP/IP is the protocol that
we use on the Internet today. Finally, people around the world could send
data to one another. But there were still a problem. The information they
sent was just text, it wasn’t centralized
and it was pretty bland. Then in the 1990s, a computer scientist
by the name of Tim Berners-Lee invented
the worldwide web. It utilized different protocols for displaying information in webpages and became
the predominant way of communication and
accessing the Internet. Anyone who had an
Internet connection at that time was able to access the information
source of the World Wide Web. It’s been 30 years since the creation of the
World Wide Web. We’ve gone from sending
simple email messages in the viewing basic
web pages to having video chats and
instant news updates, order food, buy books, and even cars in a
matter of seconds, taking the online
course like this wasn’t even possible
until recently. The creation of the
Internet that we know today was the
culmination of knowledge and engineering from many brilliant scientists
and organizations.

We’ve mentioned IP addresses
a lot in this course, but we haven’t actually gone
into detail about them. There 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. 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. 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. 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 6 addresses, IPV6 addresses
consists of 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’ll start seeing more and more IPV6
addresses in the wild. An example of IPV4 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 two to the 128th power
possible IP addresses. Two to the 128th power is
an insanely huge number, so huge that
scientists had trouble describing with words just
how big this number is. 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’s not even close to the number
we’re talking about. Now, take all the grains of
sand in the entire world. Assuming there are roughly
seven and a half times ten to the 18th power grains
of sand in the world that still wouldn’t be
enough IPV6 addresses. Now, let’s take all the
sand from multiple Earths. Now you’re close to what
that number would be. It’s a crazy large number. Just know that we won’t
be running out of IPV6 addresses anytime soon. Another mitigation tool
that we’ve 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 that like a
receptionist that a company. You what number to dial
to get to the company. 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’re an IT support specialist
is to configure NAT on a router to facilitate communication between your company’s network
and the outside world.

Limitations of the Internet in IT

The Internet is a powerful tool that has revolutionized the way we live and work. However, it also has some limitations. IT professionals should be aware of these limitations so that they can plan for them and mitigate their impact.

Here are some of the limitations of the Internet:

• Security: The Internet can be a dangerous place. There are many threats to security, such as malware, phishing attacks, and cybercrime. IT professionals need to take steps to protect their networks and systems from these threats.
• Reliability: The Internet is not always reliable. Outages and performance problems can occur for a variety of reasons. IT professionals need to have plans in place to deal with these outages and performance problems.
• Cost: The Internet can be expensive, especially for businesses and organizations that need high-speed bandwidth and reliable uptime. IT professionals need to budget for the cost of the Internet when planning their networks and systems.
• Bandwidth: The amount of data that can be transferred over the Internet is limited by the bandwidth of the connection. IT professionals need to be aware of the bandwidth limitations of their networks and systems when planning for applications and services.
• Latency: The time it takes for data to travel over the Internet, also known as latency, can be an issue for some applications and services. IT professionals need to be aware of the latency requirements of their applications and services when choosing an Internet connection.

In addition to these general limitations, there are also some specific limitations of the Internet in IT. For example, the Internet can be used to spread misinformation and disinformation. It can also be used to harass and bully others. IT professionals need to be aware of these potential problems and take steps to mitigate them.

Here are some tips for mitigating the limitations of the Internet:

• Security: Implement security measures such as firewalls, intrusion detection systems, and encryption to protect your networks and systems from threats.
• Reliability: Use a reliable Internet service provider and have backups of your data in case of an outage.
• Cost: Choose an Internet service plan that meets your needs and budget.
• Bandwidth: Use a high-speed Internet connection if you need to transfer large amounts of data.
• Latency: If latency is an issue for your applications and services, choose an Internet connection with low latency.
• Misinformation and disinformation: Educate your users about the dangers of misinformation and disinformation and how to identify it.
• Harassment and bullying: Have policies in place to deal with harassment and bullying online.

By being aware of the limitations of the Internet and taking steps to mitigate them, IT professionals can help to ensure that their networks and systems are secure, reliable, and secure.

[MUSIC] A lot of the skills from my previous jobs, such as at the call center that I can
apply now, is my attention to detail. Having the soft skills of being creative,
thinking outside of the box, those have all helped
me in my new position. >> All the jobs that I’ve had prior to IT, their main fundamental
was customer service. It’s that same customer service
fundamental that has transferred to my current IT position. >> I definitely think that working,
especially for the police department, did get me prepared for this. Because when you’re
working in a 911 center, you really never know
what’s going to happen. >> I was already in a really high
position as a restaurant manager, and that’s when I felt like I plateaued. I couldn’t do that for
the rest of my life. And here I am as an IT
consultant entry level. I have health insurance. I have plenty of time off. [MUSIC]

There’s no doubt that the
Internet has made it much easier for us to connect
with our friends and family. But it’s also made it easier to connect with everyone
else in the world. We’re no longer confined to
our local neighborhoods. Decades ago, if you
wanted to sell something, you’d place your goods
in your driveway and put up signs
for a garage sale. The only way someone
would see this is if they drove by your neighborhood
and saw your sign. We got a little more
savvy and started advertising in our
local newspaper. We had to pay to list their ad, but at least we were able to reach more people in
our neighborhood. Then the Internet boom happened, and we can use sites
like Craigslist to post an advertisement for free and reach more
people in our city. Then we were able to sell to
people outside of our city, to cities and other states. Eventually, we could sell
the people outside of our own country all
thanks to the Internet. Globalization is the movement that let’s governments,
businesses, and organizations
communicate and integrate together on
an international scale. It’s been made possible by the internet and
information technology. Countries can communicate
with each other faster. News happening on
the other side of the world reaches
us before we can blink and global and financial trade
has increased dramatically. Globalization has transformed
almost every aspect of human society as we know it. Media and social movements
have become globalized too. In 2011, several countries
in the Middle East started riots and protests against their
government regimes, known as the Arab
Spring protests. Because of outlets
like social media, their movement gained worldwide
attention and citizens of many different countries banded together to take
collective action. Social media movements like this have been
going on for years, gathering together people
from all over the world and unifying them
under a single cause. The Internet has
also dramatically changed the way we
consume entertainment. A few years ago, if you wanted
to watch something on TV, you’ve got to actually
sit in front of your TV right when it aired
or else you’d miss it. Then we started
recording our shows first on VHS and then
on things like TiVo, so we can watch them later. But now we have access to more TV shows and movies than we can ever watch in our entire
lifetime at our fingertips. What if you wanted to listen to a new song by your
favorite band? You used to have to wait until they release
their album in a store. You couldn’t just buy one song, you had to buy the
entire album on a CD, cassette tape, or even a
vinyl record back in the day. If you want it to
get the day’s news, you had to wait
until the next day when the newspaper
would print it. Even then you
weren’t able to get a fraction of a fraction of a fraction of the news you can get on the Internet today. Retail stores aren’t
the only place you look when you want to
buy something anymore. Now you can order food, clothes, books, and well, just about
anything on the Internet. But you don’t just buy
stuff off the web. You can even get an education. Colleges and universities
worldwide are taking education out of the classroom and putting it into your homes. Online courses are becoming a popular way for people to get a quality education at a more convenient
location, time, and price. It’s not just degrees. There’s an almost
infinite amount of educational tools
available on the Internet. A few years ago, all
this information on the Internet had to be reached through your laptop or desktop. Now, more than ever, people are going mobile and can access all of this information
with their smartphones. It’s truly an amazing time to be alive in this technological age. The takeaway here
is that the only constant in the field of
technology is change. As an IT support specialist, You’ll have to stay on
your toes to keep up with this dynamic
shifting landscape.

Impact of the Internet Tutorial

The Internet has had a profound impact on every aspect of our lives, from the way we communicate to the way we do business. Here is a brief overview of some of the key impacts of the Internet:

Communication: The Internet has made it easier than ever to stay in touch with friends and family members around the world. We can communicate with each other through email, social media, and video chat. The Internet has also made it possible for us to connect with people who share our interests, regardless of where they live.

Business: The Internet has revolutionized the way businesses operate. Businesses can now reach a global audience with their products and services. The Internet has also made it possible for businesses to automate many tasks, which has led to increased efficiency and productivity.

Education: The Internet has made education more accessible and affordable. Students can now take online courses from top universities around the world. The Internet has also made it possible for students to access a wealth of educational resources, such as online libraries and databases.

Entertainment: The Internet has changed the way we consume entertainment. We can now watch movies and TV shows on demand, listen to music streaming services, and play games online. The Internet has also made it possible for us to create and share our own content with the world.

Commerce: The Internet has made it easier and more convenient to buy and sell goods and services. We can now shop online from retailers all over the world. The Internet has also made it possible for us to start our own businesses with relatively low upfront costs.

In addition to the impacts listed above, the Internet has also had a significant impact on the following areas:

• Government: The Internet has made it easier for citizens to participate in the democratic process and to hold their governments accountable.
• Healthcare: The Internet has made it easier for patients to access information about their health and to find healthcare providers.
• Transportation: The Internet has made it easier to plan and book travel.
• Science and research: The Internet has made it easier for scientists and researchers to collaborate and share information.

Overall, the Internet has had a positive impact on society. It has made our lives easier, more convenient, and more connected. However, it is important to be aware of the potential negative impacts of the Internet, such as cyberbullying, online scams, and the spread of misinformation.

Here are some tips for using the Internet safely and responsibly:

• Be careful about what information you share online.
• Be aware of the risks of cyberbullying and online scams.
• Be critical of the information you find online.
• Take breaks from the Internet and spend time with friends and family in person.

The Internet is a powerful tool that can be used for good or for bad. It is important to use it responsibly and to be aware of the potential risks.

Internet of Things (IoT) Tutorial

The Internet of Things (IoT) is a network of physical objects that are embedded with sensors, software, and other technologies to connect and exchange data with other devices and systems over the internet. These devices range from simple everyday objects, such as thermostats and light bulbs, to industrial machines and complex systems, such as self-driving cars and smart cities.

IoT devices collect and share data about their environment and usage patterns, which can be used to improve efficiency, automate tasks, and make better decisions. For example, a smart thermostat can learn your daily routine and adjust the temperature in your home accordingly, saving you energy and money. A smart irrigation system can track the weather and soil conditions to water your lawn only when needed, conserving water.

IoT devices are becoming increasingly common in our homes and workplaces. Here are just a few examples of IoT applications:

• Smart homes: IoT devices can be used to automate many tasks in the home, such as controlling lights, thermostats, and security systems. This can make our lives more convenient and save us time and money.
• Smart cities: IoT devices can be used to improve traffic flow, reduce energy consumption, and monitor air quality. This can make cities more livable and sustainable.
• Wearable devices: IoT devices, such as smartwatches and fitness trackers, can track our health and activity levels. This data can be used to improve our health and fitness goals.
• Industrial IoT (IIoT): IoT devices are being used to improve efficiency and productivity in manufacturing, healthcare, and other industries. For example, IoT sensors can be used to monitor the condition of equipment and predict when it needs maintenance.

The IoT is still in its early stages of development, but it has the potential to revolutionize many aspects of our lives. Here are just a few of the ways that the IoT could impact the future:

• Personalization: IoT devices can collect data about our individual preferences and habits. This data can be used to personalize our experiences, such as recommending products and services that we are likely to be interested in.
• Autonomy: IoT devices can automate many tasks that we currently perform manually. This could free up our time for other activities and make our lives more convenient.
• Efficiency: IoT devices can help us to use resources more efficiently, such as energy and water. This could save us money and reduce our environmental impact.
• New products and services: The IoT is enabling the development of new products and services that were not possible before. For example, self-driving cars and smart cities are just two examples of new products and services that are being made possible by the IoT.

The IoT is a powerful technology with the potential to improve our lives in many ways. However, it is important to be aware of the potential challenges and risks associated with the IoT, such as cybersecurity and privacy concerns.

Here are some tips for using the IoT safely and responsibly:

• Be careful about what information you share with IoT devices.
• Choose IoT devices from reputable manufacturers.
• Keep your IoT devices up to date with the latest security patches.
• Use strong passwords for your IoT devices and change them regularly.
• Be aware of the privacy settings on your IoT devices and configure them to protect your privacy.

The IoT is still a new technology, but it is one that is rapidly developing. It is important to be aware of the IoT and its potential impact on our lives.

You may have heard of
the phrase Internet of Things or IoT. This concept is pretty new, but already has a major impact on the future of computing. The concept is fairly simple. Basically, more and
more devices are being connected to the
Internet in a smarter fashion. Did you know that there
are now smart thermostats. Instead of manually programming them when you’ll be
out of the house, they’ll just know
when you leave and turn off the air
conditioning for you. It’s not just your thermostat. Many companies out there are making smarter
household devices. There are fridges that can keep track of what foods
you have in there, toasters that can be
controlled by your smartphone, lights that can change
depending on your mood and cars that drive you instead
of you driving them. The world is moving
towards connecting manual devices to the internet
and making them smarter. These decisions have many
societal implications though, especially when it comes to cybersecurity, or
personal privacy. But there’s also a huge
potential for IoT to completely transform the world in ways we have yet to see. In the future, people may
be shocked to learn that we had to do manual things
like make your own coffee, or drive to the grocery store. While you may not experience working with an Internet
of Things device, you should be aware
that it will become a large part of the
future of computing.

My name is Gian Bokassa, and I’m a Program Manager with
the Android Security Team. The Android Security
Team is responsible for protecting over two billion Android devices
are on the world. But specifically, what I
do with the team is I work with anywhere from the
end-users to our partners, all the way up to the
engineering teams within Google on each Android
dessert release, which is what we call
versions of Android. Depending on what
needs to be done for that release and that
cycle, I’m the person. We have lots of discussions with external partners and
phone manufacturers on helping them adopt
new security features that run on Android for
their next phone release. Internally, we’re
always trying to think one step ahead and
try and think of what the next vulnerability or next area that we can improve
the platform exists in. Security is important to
everyone in the chain because as more and more of our
data becomes digitized, it’s even more important
to keep it all protected. From a programming perspective, you can say build
a secure system. But if there’s one
flaw somewhere in that software and that
flaw could be one byte. The whole system could be open insecure and anyone
can just take it down.

The added convenience made
possible by the Internet also makes it harder and harder
for us to maintain anonymity. When you purchase
something online, you’re buying habits
can be logged, and you may be targeted
with marketing, even when you want to
do something simple, like book a dinner reservation, your name, phone number, email, and maybe even a credit
card number are required. Now think about the
information you post publicly; name, pictures, family, friends, and even your location may be available
to anyone online. Be aware of what you’re
sharing by reviewing the privacy policy of the
service before you use it. It’s up to you to decide
if the trade-offs of a service are worth sharing
your personal information. In most cases,
companies are trying to build great products that
make our lives easier. They may offer their
products for free because you provide
them with free data. Just make sure your information won’t fall into the wrong hands. Privacy doesn’t just affect
us on a personal scale. It’s also become a
concern for governments. In Europe, data regulation
and privacy are strictly protected to help EU citizens gain more control over
their personal information. COPPA, or the Children’s
Online Privacy Protection Act, also regulates the
information we show to children under the age of 13. There are many more examples of government regulation
of privacy. It’s no longer
something we can think of on an individual scale. Another concern that’s
grown with the rise of the Internet is the
issue of copyright. Imagine you create
a beautiful graphic and upload it on the web
for your friends to see, then some random stranger
takes your graphic, claims that as their own, and sells it for profit. Thankfully, several companies have been founded and designed specifically to help
solve this issue of copyright and intellectual
property theft. There are also efforts in place that you’ve
learned about, like open source projects that benefit from
being on the Internet. In these cases,
open collaboration allows a project to thrive. On top of privacy and
copyright considerations, computer security is
another issue that you may face in both your personal
and professional life. More and more
companies are being targeted in
cybersecurity attacks. For example, the WannaCry
attack that started in Europe, infected hundreds of thousands of computers across the world. The financial loss
of that attack has been estimated at over
a billion dollars. Hospital computers
were even infected. In a critical life threatening moment,
every second matters. Not being able to perform
basic medical duties, like pulling medical
records took time away from
doctors and nurses, and more importantly, the
lives of their patients. Before the WannaCry attack, there were lots of other
worldwide attacks. In 2011, the Sony PlayStation
network was attacked and around 77 million user accounts had personal
information exposed. Everything from entire
governments to businesses that handle the data of millions of people have been compromised. Computer security is no longer the job of specialized
security engineers. It’s everyone’s responsibility. As an IT support specialist, you’ll need to have a
fundamental understanding of computer security. I spend every day
working in security. I love working in the field
because I get to help protect people and their devices
from all over the globe.

Privacy and Security in IT

Privacy and security are two of the most important considerations in IT. Privacy is the right to keep your personal information confidential. Security is the protection of your data and systems from unauthorized access, use, disclosure, disruption, modification, or destruction.

Privacy

There are a number of things you can do to protect your privacy online:

• Be careful about what information you share online. Only share information with trusted websites and services.
• Review the privacy policy of a website or service before using it. This will tell you what information is collected and how it will be used.
• Use strong passwords and enable two-factor authentication whenever possible.
• Be careful about what links you click on and what attachments you open. Phishing attacks are a common way for hackers to steal personal information.
• Use a VPN when connecting to public Wi-Fi networks.

Security

There are a number of things you can do to protect your security online:

• Keep your software up to date. Software updates often include security patches.
• Use a firewall and antivirus software.
• Be careful about what files you download and what websites you visit.
• Back up your data regularly.
• Be aware of common scams and attacks.

Additional tips for IT professionals

As an IT professional, you have a responsibility to protect the privacy and security of your organization’s data and systems. Here are some additional tips:

• Implement and enforce strong security policies and procedures.
• Train your employees on security best practices.
• Regularly monitor your systems for suspicious activity.
• Have a plan in place to respond to security incidents.

Conclusion

Privacy and security are essential in IT. By following the tips above, you can help to protect yourself and your organization from cyber threats.

[MUSIC] My name is Heather Adkins. I’m director of information security and
privacy here at Google. And our job is to keep the hackers out. Every day at Google for me is a new day. It’s like a new job every day. Hackers are very interesting and very
diverse in the way that they do things. They’re either hacking for fun and fame
because they’re intellectually curious and they want to understand how things work. Or they’re hacking for money because
they want to steal money from people or they’re hacking because they
want to steal information. And so for us we try to understand
how the hackers work so that we can understand what kinds of things we have
to do to prevent them from doing it. You have to understand
how the internals work, you have to understand how the programmer
built it, and this is really thrilling. You get to ride alongside
the programmer and understand what they were thinking when
they were designing the software and anticipate what mistakes
they might have made. We prepare for being hacked by
understanding how hacking works. And this is often the most exciting
part of our work because we get to break the systems and I think a lot
of us who get into the field think what would it be like to rob a bank, what
would it be like to hack into a system? And here we get to play
the other side of that. So we have hackers of our own who hack
our systems and tell us how they did it. And we also study how the actual attackers
in the world are hacking other people. I think that the field of security is so
exciting for us, those of us who do it as a profession,
because it’s changing all the time. That presents us with new
challenges every single day. And it also appeals to us, I think because
it means that we’re protecting users. Google has a service offered to
billions of people on the planet, and we do it because we want to protect them. [SOUND]

The world changes. Things change. I was cleaning up the other day, and I was throwing away old disks from our first computer, those little floppy disks. Nobody use that anymore. But I thought floppy disks
were cool back then. So if I weren’t a
lifelong learner, I’d still be stuck
like that floppy disk. I believe it’s never too late
to go in a new direction, and I think IT is my thing. I think that’s going
to be my thing.