A new section of each course starts monthly. If enrolling in a series of two or
more courses, please be sure to space the start date for each course at least two
months apart.
All courses run for six weeks, with a two-week grace period at the end. Two lessons
are released each week for the six-week duration of the course. You do not have
to be present when lessons are released. You will have access to all lessons until
the course ends. However, the interactive discussion area that accompanies each
lesson will automatically close two weeks after the lesson is released. As such,
we strongly recommend that you complete each lesson within two weeks of its release.
The final exam will be released on the same day as the last lesson. Once the final
exam has been released, you will have two weeks to complete all of your course work,
including the final exam.
Week One
Wednesday - Lesson 01
In our first lesson, you'll learn about the concept of a network stack. After a succinct review of essential network and networking terms, we'll compare the theoretical structure of a network stack—commonly called the OSI model—to real-world networking. We'll then trace how data travels through the computer for transmission on the network.
Friday - Lesson 02
We'll pick up right where the last lesson left off today when we begin our discussion on how a unit of computer data—called a packet—gets from one computer to another. You'll learn all about how packets are formed, how packets are sometimes chopped then reassembled to go across WAN links, and how the receiving computer handles packets upon arrival. You'll also learn why the network's most important device is the router.
Week Two
Wednesday - Lesson 03
Today's lesson is dedicated to helping you understand how routers operate. You'll learn all about how routers create a virtual map of the entire Internet. You'll also see how routers connect to different network types—an Ethernet segment and an ATM link, for example—transmit data across those different mediums. Then we'll discuss why routers have their own special languages, called routing protocols.
Friday - Lesson 04
Today you'll learn the language of routers: routing protocols. You'll learn why some routing protocols are appropriate for smaller networks, and why very large networks require specialized routing protocols. You'll also learn about the two most revealing measurements of a router's capability: latency and packets per second (pps).
Week Three
Wednesday - Lesson 05
You've heard of TCP/IP, but its details may seem mysterious. After you complete this lesson, those mysteries will be banished forever! You'll learn about IP addressing, the four primary IP address classes, and all about the various protocols that come packaged within TCP/IP. Prepare to demystify TCP/IP!
Friday - Lesson 06
Security is on everyone's mind these days, so in this lesson, you'll learn the fundamentals of how computers enforce security. You'll learn what a security descriptor is and how it can allow some people to only read a document, while others can delete or modify the document as much as they like. You'll also learn the difference between a security implementation and security protocols. Finally, you'll find out how security operates in a Windows environment, including exactly what happens during log on, authentication, and authorization.
Week Four
Wednesday - Lesson 07
In today's lesson, we'll explore encryption, a method used to secure data for transmission over the Internet. You'll learn about various encryption schemes, and you'll get firsthand knowledge of how a chunk of data gets encrypted, how it gets decrypted on the receiving end, and how this process can be secure. You'll also learn how Secure Sockets Layer (SSL) makes it safe for you to order merchandise online, and how SSL ensures that your connection to the seller's Web site is secure.
Friday - Lesson 08
The Internet is a great public network, but what if you need it for private communication? For example, what if a salesman needs to make a private connection to her company's network to check on special bulk pricing? In today's lesson, you'll learn how you can create a virtual private network out of your Internet connection. You'll get a hands-on view of how these private connections are made, and why they're so useful.
Week Five
Wednesday - Lesson 09
The Internet, and almost every other network today, uses Domain Name System (DNS) to translate names we understand (like www addresses) into IP addresses that computers can use. It's important to understand how this system works, so in this chapter you'll learn details about how DNS operates. You'll learn how resource records are the building blocks of DNS, and how DNS scales to the entire Internet by being broken into zones.
Friday - Lesson 10
We'll expand on our discussion of DNS in this lesson. Here you'll learn about the most important types of resource records, including A records, SOA records, and others. You'll also learn about the two types of DNS queries: recursive and iterative. There are many other resource record types, and you'll learn about those today, too. By the end of this lesson, it'll be clear just how important DNS is to our daily lives!
Week Six
Wednesday - Lesson 11
In this lesson, you'll learn how Internet Servers operate, including how a Web page is requested and transmitted to your computer, then displayed on your screen. You'll also learn about the two primary Web protocols—HTTP and HTML. There are other Internet-based services, such as e-mail servers, news servers, and instant messaging, and we'll investigate those in this lesson, too.
Friday - Lesson 12
Have you ever wondered about the difference between a desktop computer and a server? Have you heard of cloud computing, but don’t know exactly what it means? In our final lesson, we'll go over the differences between server-class operating systems and server-class computers, and we’ll talk in-depth about the various hardware components that comprise a true server-class computer. Understanding why a desktop computer shouldn't be used as a departmental server is important! You’ll also learn what cloud computing is, why it’s such a compelling platform, and how datacenters provide all that computing power.