By Marilyn Ellis
Before starting coursework on network systems such as Novell or Windows NT, students need a solid and comprehensive foundation in basic computer networking. Understanding protocols, cabling, cable connectors, network cards, phone line types, and wireless communications is fundamental to understanding and managing a network system. This basic knowledge will also help students learn the various network topologies (bus, star, and ring configurations) and types of networks (peer-to-peer and client/server).
I incorporated as much hands-on experience as I could into the network fundamentals class I taught because hands-on work was not used in the training I had taken and because new textbooks are incorporating hands-on examples.
Hands-on training comes with all distance-learning classes because of the nature of the class. Students experience working with one type of network (the Internet) through e-mail, chat, and Internet research. Students also complete work at home on their own PC.
The challenge in the classroom was to create this same “networking environment” for students taking the course on campus. Although the book had plenty of assignments designed to do this, my students learned the college network by using it every day, similar to what the Internet class had experienced on the Web.
Start with shared folders
To start the first lesson, I created a shared folder on my teacher computer. Second, I printed a handout showing students how to set up their own folders for sharing. When they finished the setup, I gave them the pathway to my share, where I posted all instructions and homework assignments for them. They would get what they needed, print it out, and turn in answers for homework. I did not provide them with any more paper handouts after this exercise.
Students also created shares with each other to work on their final group projects. First, they had to create shares for each computer in their group, which could be password protected, then they posted and edited their work for their final project back and forth across the network.
Class information on the network
In addition to using shared folders to familiarize students with working on a network, I kept electronic versions of tests and reference material on the network as well. A body of references for the course was online at the college’s main computer, and I gave the pathway link to my students. At the large reference site, they found weekly quizzes, printed them, and answered the questions, which they turned in for a grade.
Also, students were required to take exams online. The exams were scheduled for a certain date and time during the class period. I set up exams with Course Test Manager by Course Technology, and set user names and passwords for each student so they could access the online exam. When students finished the exam, they clicked a button to get their score as well as instant feedback on the questions they missed.
Watching data transfer with Network Monitor
In addition to understanding navigation on a network, I wanted my students to understand how data was physically transmitted. To make this easier to understand, I set up Network Monitor on my computer, and used it to illustrate the seven-layer Open Systems Interconnection (OSI) reference model. This model is a framework for understanding how information is passed from one computer to another. Many systems—including Novell, Windows NT, Mac, SNA, and UNIX—are based on this standard.
According to the model, the sending computer adds bytes to a data frame before sending it to the network. These bytes can compress the data, add address information for both sending and receiving computers, and check for errors. The receiving computer network then strips off all the added data until only the session message is left.
Network Monitor reads the incoming frame information and shows the number of bytes in the frame as it enters the system. For example, the total frame length of a piece of data is 228 bytes. Bytes are stripped off as the data passes through a layer, so that after the IP layer, there are 214 bytes remaining, after the TCP layer, 174 bytes. The Session Message in Network Monitor correlates with the Application layer of the OSI model, and is the size of the actual data in the frame. The rest of the data in the frame correlates with the Presentation, Session, Transport, Network, Data Link, and Physical layers of the model, each adding its own transportation information.
Once the students had seen me use Network Monitor, they downloaded the executable file, installed Network Monitor on their computers, and ran a small capture of data to examine themselves.
Hands-on work to reinforce the theory
In all my network classes, I held tours, many at computer companies like Compaq, or engineering firms like Fluordaniel. This particular class had a tour of the network room at the college. Students had a chance to talk to the technicians, and view servers, wiring configurations, hubs, phone lines, and other hardware housed in the main network room at the college. Then they examined a wiring closet in another building on campus.
To add to this hands-on experience, I brought in many types of wires, network cards, motherboards, RAM chips, and other hardware to class for students to examine. They practiced snapping network cards into the motherboard, and examined the wiring and the punch down cards to get a feel for what they were studying.
A good beginning
When the students finished this networking fundamentals class, they had learned more than just information from a book and were better prepared to take the exams necessary to get their MCSE or NTE, although a great deal more class work is required beyond this course.
Do you teach fundamentals before going into the specifics of a certain type of network? How do you illustrate network topologies or the OSI reference model? Send us your tips for teaching networking so we can share them with other readers.
Marilyn J. Ellis, MCSE, has a master’s of science in occupational education with a specialization in training and development that included graduate courses taught with various distance learning techniques. From January 1998 through July 2000, she taught data communications in the classroom and online at Tomball College in Tomball, TX.