The teaching methods reviewed are all alternatives to the traditional direct-instruction approach in which a teacher presents information to a class via a lecture. The researchers created a categorisation system for the various teaching methods used in the research papers: visualisation methods, virtualisation methods, active-learning methods, and practical hands-on lab exercises.
Packets of data move around a computer network invisibly, and so it can be difficult for learners to understand the various protocols and stages involved in network data transmission. Visualisation techniques allow learners to ‘see’ the journey that data takes across a network. Some examples of teaching activities using these techniques include using animation or a multimedia presentation to show learners what happens as data moves from one point in a network to another. Packet tracing can also show the ‘hops’ that data takes in a more concrete way. There are also network simulator applications that can simulate the layered network model and the details of network protocols.
Virtualisation methods use a type of learning environment that combines real network devices with simulation-based design. You can use tools to help create virtual labs, such as virtual machines, which allow students to experiment with real network devices via remote, internet-based connections. These techniques allow students to learn from any place and without time limitations. This approach has been shown to be beneficial for students because it enables them to experiment and learn from their mistakes (helloworld.cc/cui2012).
The review of existing research found that many courses use active learning methods to help learners engage with networking topics. An example discussed in this category of teaching approaches is cooperative learning, which involves students working together to achieve a common learning goal. It encourages critical thinking and helps students to develop communication skills. In this type of learning, the teacher has a supportive role and the students collaborate to share ideas and solve problems. Teachers can combine cooperative learning activities with problem-based learning, in which they design a network with deliberate errors and learners work together to discover the cause of the network failure.
Finally, hands-on lab exercises involve learning about networks by configuring real equipment, although the researchers note that the existing research suggests these types of learning activities depend on first understanding the theory behind network design.
Benefits and challenges
In the reviewed literature, the researchers found a number of advantages of using the various methods. Some of these advantages are practical: for example, it can be cheaper to use virtualisation methods than hands-on lab exercises. Other benefits relate to the motivation and engagement of students, which studies suggested are increased by using the active-learning paradigm. Perhaps most importantly, some benefits relate to the skills students develop and the knowledge they gain. Visualisation methods support students’ understanding of some very abstract theoretical topics by tracing packet journeys across a network. Meanwhile, in hands-on lab exercises, scenarios involving fixing faulty networks were shown to develop students’ critical-thinking skills.
Thinking about the challenges of using these methods, it’s perhaps unsurprising that educators had to overcome problems with group working and motivation when using active-learning techniques, while in hands-on lab exercises, the difficulties related to troubleshooting the technical equipment. The technical expertise required by both teachers and students to successfully set up and complete learning exercises was also highlighted as a potential challenge in virtualisation activities. However, research into visualisation techniques found that most potential challenges related to student understanding of the underlying theoretical concepts — studies that explored the use of analogies, animations, and multimedia found a risk of superficial learning or student misconceptions.
Many of the research studies included more than one of these teaching methods. Although the researchers did not find any evidence to suggest that there was an ideal combination of methods, the analysis suggests that a mixture of theory and practical learning activities is essential.
Effective learning about computing
The research review found evidence that all of these teaching methods led to greater learning gains than traditional direct-instruction methods. Some of the researchers’ conclusions applied across all the teaching methods, as follows:
Using step-by-step instructions: in some learning activities, such as device configuration, it is essential to follow a set of instructions. However, as these limit students’ critical thinking about the task they are performing, the researchers suggest that educators avoid these where possible.
Virtual versus practical: studies suggest that students learn more when using virtual labs than when taking part in hands-on activities, because their learning has fewer distractions and is more task-focused.
Matching methods to topics: the team concludes that there is not yet enough evidence in the existing research to decide which method is suitable for each topic in a computer networks curriculum. They suggest that this would be a useful focus for future research.
You can read about some of these methods in action in this issue: check out the article on page 22 for a summary of network simulator tools, or Ben Hall’s article to learn about an active-learning technique for primary students.
Classifying networking teaching
Four overarching methods for teaching about computer networks are presented in the research, as follows:
Visualisation techniques: Animations, network simulators, multimedia presentations, packet tracing, visual analogies
Virtualisation methods: Setting up a network in a virtual lab that accesses real-life equipment via a configured connection
Active-learning methods: Student collaboration and competition, problem-based learning, playing games, failure and counter-examples
Practical hands-on lab exercise: Setting up a network in a hands-on lab using real-life equipment