INT - How the Internet Functions (Lesson)

How the Internet Functions

Introduction

Now we are ready to examine the internet and how we use it. The world wide web is like a giant library of information. The library is housed all over the world. The Internet allows you to access and exchange information with others in a global network, allowing communication with people wherever they are connected to the internet. Add a computer, smartphone, tablet, or other device that allows internet access and you are connected. This is end node connection architecture. The end nodes are the smarter components; the internet is the travel network to pass the information.

The internet, with the help of a search engine (browser), allows us to type in words to help us locate information and provides addresses for the information through the use of the www. Remember the web allows us to select, retrieve, and use the information, the internet connects the computers to allow us to access to facilitate the transfer of the information to our computer.  The purpose of the internet is to allow for the transfer of information around the world.  The function of the internet is how the internet works to meet the purpose of the internet.

In 1974 Elizabeth Feinler and her group at the Network Information Center of Stanford Research Institute developed and controlled the assignment of the first Domain Names, creating the need for domain name servers (DNS) of today. A DNS is like a phonebook. The servers (a large computer) takes the domain name, www.gavirtualschool.org, and looks it up and find the associated IP  (Internet Protocol) address, like we would have looked up a phone number in a printed phone book by a person's name not that long ago. The DNS then provides the IP address needed to reach the domain name that you requested. Now, the message can be used on the internet as everything is routed using the IP address of the computing device connected to the internet. Are all computers connected directly to the internet? No, many are connected within a controlled network which has a computer or router connected to the internet to send messages onto the internet. At home, you may have a router and a local area network, thus you will have internal IP addresses for your home devices, assigned by the router, and not actual internet IP addresses. In an office or school, there may be a local area network within a wide area network. Access to the internet is controlled through the servers of the school or the office, and your computer does not necessarily go directly to the internet.

When you search for a topic, a list of information is displayed by the search engine, a software program that helps you locate information. It is important to review the list and pick appropriate sites of authority if we are doing a paper. If we are looking for the journal thoughts of others we may look for a blog, opinions of the blog creator and others that post to the blog. Not exactly an authority site. Looking at the ending of the URL helps identify the authority of the information. Here are some common endings and their meanings.

  • .com - a commercial site, a business
  • .edu - an education site, colleges, universities, and other education levels
  • .gov - reserved for US government sites
  • .net - mostly internet provider sites
  • .org - an organization which may be for profit or not for profit

Note that this is not an exhaustive list. Just as the United States uses .gov and .us for some of sites within the country, other countries have "." endings as well. Regardless of the type, verify information for credibility. Some .edu sites at universities may lend space to students. Students are not the education entity authority.

IP - Internet Protocol

When we ask for information on a particular topic, information is retrieved based on the URL, the uniform resource locator and returned to our computer for us to examine and use.

What is key to the address that your device or router is given when it is connected to the internet?

IP stands for Internet Protocol. Watch the video below to find how the request from your computer gets to where it needs to go and returns information back to you.   Note that this is done in small pieces called packets. Packets allow information to travel in smaller pieces to allow faster travel of all information. The information must then be reassembled when received.

Data Flow on the Internet

Now watch the more detailed information on packet switching. Information that you request or send over the internet is broken into packets, not necessarily traveling the same method to the destination computer and then reassembled to be handled by the receiving computer.  

Spanning Tree Algorithm

Below is Radia Perlman's Spanning Tree Algorithm poem to explain the algorithm.  An algorithm is the method , the steps, to solve a problem. Getting the packets from one place to another required creating a network that allowed for different routes like branches of a tree to get packets within a corporation, university, or other internal internet (intranet) out to the internet to be routed to where they need to go.   As noted in the video, packets will travel in different routes and be reassembled at the destination computer to allow for faster travel.   Note, spanning trees are not new, but the use of the algorithm to connect internal intranet to the outside internet was important in the development of the wide spread use of the internet by many people. Previously only a few computers could be connected together.

text of poem Algorhyme

Perlman is now working on a new algorithm called TRILL (Transparent Interconnection of Lots of Links) using a new method of forwarding Ethernet packets to the internet. 

 

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