Project 3: Representing to Learn

Gems of Pedagogy
Participant: Dan Loos
January 2012

Project 3: Representing to Learn

Research Project

In NET 120 students learn about and must memorize the Open Systems Interconnection (OSI) model. This model is a theoretical model that describes procedures and standards for how data is sent over a network. There are seven layers to the model and each layer explains the function of each level, the protocols used at each layer and how each layer interfaces with the layer above and below it.

Because the model is theoretical and the textbook descriptions of each of the layers are filled with details and technical terms that students have yet to experience or see in action, it is hard for students to understand the purpose and usefulness of the model and to visualize what the OSI model is representing.

To help students visualize what the model is trying to convey, I will give the students two tasks, both of which will ask students to trace an email message from sender to receiver using the OSI model. See the written directions to students at the end of this document.
Task 1
The first task will ask students to trace an email message from the sender to the receiver through the 7 layers of the OSI model in the form of puzzle pieces. There will be a total of 14 pieces. Students will need to put the pieces together in the correct OSI layer order--from the email message being typed and processed to the data being ready to travel over a network (via cable or air). At the receiving end, the email message data will be received and processed through the different layers in reverse order to reach the other computer. The puzzle pieces will contain a description of what is happening to the data. The students will need to put the puzzle pieces in the correct order. The students will also be given labels for the titles of each layer which they must place correctly next to the descriptions.

Task 2

The second task will again ask the students to trace the email message from sender to receiver through the OSI layers, but this time the students will be responsible for generating the map on their own.

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Demonstrating Your Understanding of the OSI 7 Layer Model Name: ______

PART 1
Directions

1. Your teacher will give you two sets of cards: 1) OSI Functional Descriptions and 2) Names of OSI layers. The cards will be mixed up.
2. You want to show the pathway of data and what happens to it when you send data from one computer to another computer over a network. In this exercise, you will use the OSI model to map the pathway of an email message.
3. In your group, place the cards on a table or desk in three columns in the correct order following the figure below.

1. In pencil, on each card draw an arrow that shows the direction of the flow of the data of the email message from sender to receiver.
2. In your group, discuss what you notice about the movement, direction, and changes to the data as it travels over the network from the sender to the receiver.
3. Gather all of the cards and place them back into their envelope.

PART 2
Directions

On the back of this paper, please draw the pathway of an email message from sender to receiver showing the movement and changes that occur to the data throughout the different levels of the OSI model. This is similar to Part 1 of this exercise, but this time you are producing and recreating the information on your own.

The students were very engaged in the task. I thought the task would be easy and that they would finish it in just a couple of minutes. In fact, it took them nearly 50 minutes to finish the task! It was very satisfying to see one of the students have an Ah Ha moment. By being able to physically hold the cards and pile them together, he understood the data transformation through both additive and decremented process of moving down through the OSI layers from the sender and up the layers to the receiver. The students gave positive feedback to the activity and I would do it again in future classes.