THE INTERNET Computer Fundamentals

TODAY I AM:  Learning about the complexity of sending messages over the Internet  Translating web addresses into IP addresses  Solving problems! SO THAT I CAN:  Understand the flow of the Internet while learning about web addresses, IPs and the DNS I’LL KNOW I’VE GOT IT IF:  I can differentiate between: WiFi, DSL and Fiber Optic  Work together with my classmates to translate messages

TERMS TO KNOW:  IP (Internet Protocol)  IP Address  DNS (Domain Name Service)  URL (Universal Resource Locator)  Internet  Network  Packets  Routing  Servers  Fiber-Optic Cable  WiFi  DSL/Cable

WHAT IS THE INTERNET? The Internet, also called the Net, is a worldwide collection of networks that links millions of busi- nesses, government agencies, educational institutions, and individuals.

WHERE DID THE INTERNET START?  Department of Defense  Goals:  Allowed scientists to share information  Function even if part of the network was disabled or destroyed  Became functional in September 1969

THE INTERNET  The Internet consists of many local, regional, national, and international networks.  Both public and private organizations own networks on the Internet.  These networks, along with telephone companies, cable and satellite companies, and the government, all contribute toward the internal structure of the Internet.

THE INTERNET Each organization on the Internet is responsible only for maintaining its own network. No single person, company, institution, or government agency controls or owns the Internet.

CONNECTING TO THE INTERNET Many home and small business users connect to the Internet via high-speed broadband Internet service. With broadband Internet service, your computer or mobile device usually is connected to the Internet the entire time it is powered on.

EXAMPLES OF BROADBAND INTERNET  Cable Internet service: provides high-speed Internet access through the cable television network via a cable modem.  DSL (digital subscriber line): provides high-speed Internet connections using regular telephone lines  Fiber Optic: Uses fiber-optic cable to provide Internet access  Fixed wireless: provides high- speed Internet connections using a dish-shaped antenna on your house or business to communicate with a tower location via radio signals  WiFi (wireless fidelity): uses radio signals to provide high- speed Internet connections to wireless computers and devices

GETTING TO A WEBSITE  All addresses inside the internet are actually combinations of numbers, rather than names.  When you ask for a specific website, the inquiry goes out to the internet to translate that name into an IP address  After a series of steps, the inquiry comes upon the DNS TranslationTable, where it can get the numerical version of the URL address that you originally entered  At last, you’re there!

BUT WAIT! Believe it or not, the Internet isn’t able to send and receive an unlimited amount of information at one time.

HOW INFORMATION IS SENT  Think of it as sending all your favorite photos to your grandma in a single envelope  It wouldn’t fit!  Break up the “packet” into smaller pieces  Send several “packets” so you can get grandma your pic s

WHAT IF THERE IS A DELAY IN THE MAIL? How will grandma know if all the “packets” arrived? How will she know what order to open them?

DNS Translation Table Code.org Thinkersmith.org CSEDweek.org CSisFun.com khanacademy.org