CSC3420 | WIRELESS AND INTERNET TECHNOLOGY | NETML

Wireless and Internet Technology Assignment 1

Assessment:

There will be five moderate-sized assignments which will all be submitted via the online peer-reviewed assessment system. The assignments will all be completed by means of an online network simulation system which makes use of the ns3 simulation system.

• • Simulation

In this course, simulation and modelling will be used as the main technique for learning and understanding. Particular use will be made of the ns3 network simulator. In previous years, in this course, the ns2 simulator was used for this purpose. These simulators have been primarily used for research in the past, however a new interface has been developed recently with the purpose of enabling undergraduate students to make use of ns3 easily for Internet and wireless network simulation and modeling.

Assignment 1

Create and simulate a network similar to the one shown here, using the Netml system.

Links

The links from A (node_0) to X (node_1), C to X, Y (node_3) to B (node_2), and Y to D (node_5) should have a capacity of 10 (in Mbit/sec), and the link from X to Y should have a capacity (d+1)/2 where d is the last digit of your student number (in Mbit/sec).

                                                                                                    

Traffic:

The lower traffic stream from A to C represents On-off traffic which sends UDP packets intensely for a period of time, and then is silent for a period of time, alternately. This trafficstream should have the following parameters set:

The Output

When we run the simulation, we want to collection information about what is happening. There are many ways to do this, so if we are not careful we will collect so much information that we will not be able to make sense of it. For example, we can turn on logging of events relating to different modules in the simulation by making appropriate selections in the ns3 dialog box.

Although we can collect vast amounts of information about a simulation quite easily, in ascii log files, or in packet capture files (pcap files), it is usually much more informative to collect information which can be displayed as graphs. The Netml system has a range of ways in which this can be done. A particularly easy way to do this is to display the throughput of each link, and of each trafficstream, by choosing the appropriate setting in the ns3 dialog for the links and traffic streams.

In this example, the main interest is on the middle link, which can easily be overloaded, because the links which feed into it have higher capacity than it. We therefore would like to know the behaviour of the buffer, at the head of the link from X to Y. To observe this turn on tracing of this buffer, which you can do using the menu of the link from X to Y. The graphs which are produced in this way should be included in your report and explanations provided of what they tell us about the simulation.

Criteria:

• A correctly formatted assignment has been prepared and submitted, including title page, section headings, appropriate headers and footers.
• All diagrams have captions and all diagrams are referenced in the text of the document, by their caption.
• A network has been created using the Netml system and is depicted in the assignment.
• The performance of the network has been monitored by creating a plot containing a graph of the throughput of each link (all these graphs should be on one plot).
• The performance of the network has been monitored by creating a graph of the throughput of each traffic stream (all these graphs should be on one plot).
• The performance of the network has been monitored by creating graphs of the level in the buffer at X.
• The behaviour of the network has been explained in words, referring to the graphs to support your explanation.