Reference no: EM132266985

Exercise - Simulation of a bottleneck

Create and simulate a network similar to the one shown in figure 1(attached), using the Netml system.

Links
The links from A (node_0) to X (node_1), B to X, Y (node_3) to C (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).

All links should use the buffer of type pFiFoFastQueueDisc with limit set to 100.

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 upper traffic stream from A to C represents a bulk ftp transfer and it should have the following parameters set:

The traffic stream from B to D is also a bulk ftp transfer and it 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 node at the head 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.

Attachment:- Assignment.rar