Introduction (3.0.1.1)
The data networks that we use in our everyday lives to learn, play, and work range from small, local networks to large, global internetworks. At home, a user may have a router and two or more computers. At work, an organization may have multiple routers and switches servicing the data communication needs of hundreds or even thousands of PCs.
Routers forward packets by using information in the routing table. Routes to remote networks can be learned by the router in two ways: static routes and dynamic routes.
In a large network with numerous networks and subnets, configuring and maintaining static routes between these networks requires a great deal of administrative and operational overhead. This operational overhead is especially cumbersome when changes to the network occur, such as a down link or implementing a new subnet. Implementing dynamic routing protocols can ease the burden of configuration and maintenance tasks and give the network scalability.
This chapter introduces dynamic routing protocols. It explores the benefits of using dynamic routing protocols, how different routing protocols are classified, and the metrics routing protocols use to determine the best path for network traffic. Other topics covered in this chapter include the characteristics of dynamic routing protocols and how the various routing protocols differ. Network professionals must understand the different routing protocols available in order to make informed decisions about when to use static or dynamic routing. They also need to know which dynamic routing protocol is most appropriate in a particular network environment.
Class Activity 3.0.1.2: How Much Does This Cost?
This modeling activity illustrates the network concept of routing cost.
You will be a member of a team of five students who travel routes to complete the activity scenarios. One digital camera or bring your own device (BYOD) with camera, a stopwatch, and the student file for this activity will be required per group. One person will function as the photographer and event recorder, as selected by each group. The remaining four team members will actively participate in the following scenarios.
A school or university classroom, hallway, outdoor track area, school parking lot, or any other location can serve as the venue for these activities.
Activity 1
The tallest person in the group establishes a start and finish line by marking 15 steps from start to finish, indicating the distance of the team route. Each student will take 15 steps from the start line toward the finish line and then stop on the 15th step—no further steps are allowed.
Activity 2
A new start and finish line will be established; however, this time, a longer distance for the route will be established than the distance specified in Activity 1. No maximum steps are to be used as a basis for creating this particular route. One at a time, students will walk the new route from beginning to end twice.
Each team member will count the steps taken to complete the route. The recorder will time each student and, at the end of each team member’s route, record the time that it took to complete the full route and how many steps were taken, as recounted by each team member and recorded on the team’s student file.
After both activities have been completed, teams will use the digital picture taken for Activity 1 and their recorded data from Activity 2 file to answer the reflection questions.
Group answers can be discussed as a class, time permitting.