[GCC-Study] Networking (2)

 

2. Limitations of the Internet

History of 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 were a programmer, you needed to directly interact with these massive computers. That would get real old real fast(빠르게 낡았다), especially if you had several people who wanted to use the only computing resource available. In 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 see 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 was 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 fixed 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. And then, in the span of 50 years, billions of computers. TCP/IP is the protocol we use on the Internet today. Finally, people around the world could send data to one another, but there was still a problem. The information they sent was just text. It wasn't centralized and it was pretty bland(지루함). Then, in the 1990s, a computer scientist by the name of Tim Berners-Lee invented the World Wide Web. It utilized different protocols for displaying information in webpages and became the predominant way of communication in 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 and viewing basic webpages to having video chats and instant news updates. Order food, buy books, and even cars in a matter of seconds. Taking an online course like this wasn't even possible until recently. The creation of the Internet that we know today was a culmination of knowledge and engineering from many brilliant scientists and organizations.

 

DARPA

 

Limitations of the Internet

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. Remember, 32 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.  Just know that we will not be running out of IPv6 addresses anytime soon.

 

Another mitigation(완화) 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.

 

IPv6

 

3. Impact of the Internet

Impact

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(실제적 지식) and started advertising in our local newspaper. We had to pay to list our ad, but at least we were able to reach more people in our neighborhood. Then the Internet boom happened, and we could 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 in other states. Eventually, we could sell to people outside of our own country, all thanks to the Internet.

 

https://en.wikipedia.org/wiki/Garage_sale

Garage sale - Wikipedia

 

https://strangerca.tistory.com/entry/%EB%AF%B8%EA%B5%AD%EC%9D%B8%EB%93%A4-%EC%9D%BC%EC%83%81%EC%9D%98-%EA%B9%A8%EC%95%8C%EA%B0%99%EC%9D%80-%EC%9E%AC%EB%AF%B8-Garage-Sale-%EA%B7%B8%EB%9D%BC%EC%A7%80-%EC%84%B8%EC%9D%BC

미국인들 일상의 깨알같은 재미, Garage Sale (그라지 세일)

 

Globalization is the movement that lets 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 have 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.

 

https://ko.wikipedia.org/wiki/%EC%95%84%EB%9E%8D%EC%9D%98_%EB%B4%84

아랍의 봄 - 위키백과, 우리 모두의 백과사전

 

The Internet has also dramatically changed the way we consume entertainment. A few years ago if you wanted to watch something on TV you had 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 could watch them later. But now, we have access to more TV shows and movies than we can ever watch in our entire lifetime right under fingertips. If you wanted 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 while 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. And 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.

 

VHS

 

That' it for the fourth module. I can learn lightly about Networking.

Make sure to have strong fundemental. 

Only practice makes perfect.