Lesson 11 - The Internet

What is the Internet?
The internet is the world's largest WAN. More than 2 billion people connect to it regularly even though in the 1990's it was limited to few people. In the 1960's the Advanced Research Project Agency (ARPA), better known as DARPA today, created the idea of the internet. They wanted to be able to access any computer regardless of the location. They created the first WAN which was called ARPANET, the first message sent through this was on October 29, 1969. But in 1983 a new protocol called TCP/IP became standard other than ARPANET. Soon after the word internet began to describe any network that used TCP/IP.

What is a protocol?
Protocols control or enable the connection, communication and data transfer between computing endpoints. Then network protocols set the rules for how computers in a network communicate with each other. The first network protocol for ARPANET was in 1969 and after a few years it was used for email, file transfers, chat services and more. By 1981 more than 200 computers were connected to the network. TCP/IP is the new standard protocol but other protocols such as HTTP (hypertext transfer protocol) or FTP are still used today.

What is DNS?
A DNS or Domain Name Service is what the internet uses to find certain web pages. When you look up a certain website domain name into a search bar the DNS goes and finds the website you searched for. It can also find websites based off of key terms you put into a search bar. the DNS searches a query for your key terms and reports back with all the relevant websites. It can even connect with other DNS to find even more specific sites.

Explain what an ISP is and what is does?
An ISP or internet service providers connect routers that are connected to both LANs and WANs to the internet. It is how data on the internet travels. Data goes from router to router to reach its destination. They first appeared in the late-1980's when the internet became more global. ISP's can include email addresses, storage, web hosting services,

What is PING and Firewall?
PING is used to check network connections. You can send a test packet over the internet and it will evaluate if they are received correctly. This tells your computer if connections are working properly. Firewall on the other hand protects your computer from internet threats. Firewall can be hardware or software, but it protects your computer from things such as viruses on the internet. They are even customizable so that you can determine what is allowed on the network and what isn't.

Connecting to the Internet
The internet is collections of small, individual networks communicating. Networks connect together to form the internet. Anywhere from individual home networks, to worldwide businesses connect together. ISP's connects to access points in other networks and are able to communicate freely. These connections are managed by backbones and routers at the highest levels. Backbones are large bundles of fiber-optic cables and routers move data between networks. These things are used to communicate with everyone else.
Internet service providers help everyone connect to the internet. ISP's provide email addresses, storage space, and occasionally web hosting services to manage websites. Customers can choose what they need and what they don't from there ISP's. Cables also are ways to connect to the internet. DSL's or digital subscriber lines are the most common types of consumer connections. They can connect to telephones, cable TV's and other things.
Computers can connect to the internet through different ways but they all are the same at the most basic level. Everyone needs a modem and and ISP. Once your modem is connected with the network it converts signals from your computer to be sent to your ISP. Finally your ISP assigns your computer its IP address which is a number that your computer is identified as on the internet. The exception is wireless devices. Instead of connecting to a modem, it connects to a wireless hub or router.