Opnet Assignment 1

Assignment 1 – Network Design and Performance

Instructions

Answer questions in this assignment inline. Please write your answers below the questions. Assignment submitted after due date will not be evaluated. Upload/e-mail a pdf version of the document.

Due Date: 5 pm, September 18, 2015.

Submitting this Assignment

You will submit this assignment on blackboard.

Write your answer and paste screenshots (if any) after each question in this document. Name the document as A1_Opnet_CSD340_John_Doe.pdf in case your name is John Doe. Upload this document by the due date and time. In case of any technical glitch with Black Board, please take error screenshot of the error

faced and email to ns997 only after submission deadline gets over. Report the error to [email protected] also with error screenshot.

Grading Criteria

Correct and to-the-point answers will be awarded full points. This assignment has 10 points (with weightage of 2% in your overall 100 points). You are required to submit it by the due date.

Introduction to Riverbed OPNET Modeler

Objective

This assignment teaches the basics of using Riverbed OPNET Modeler. OPNET’s user-friendly interface with drag-and-drop features enable students to effectively model, manage and troubleshoot real-world network infrastructures.

You will learn to create a new project and get familiar with the project editor. You will learn to create different scenarios and learn to simulate and capare results for different scenarios.

Remember that the exercise may have been created for an earlier version of Opnet. There may be slight changes in the menus and options.

Overview

OPNET provides a Virtual Network Environment that models the behaviour of networks, including its routers, switches, protocols, servers, and individual applications. The Virtual Network Environment allows IT managers, network and system planners, and operation’s staff to more effectively diagnose difficult problems, validate changes before they are implemented, and plan for future scenarios such as traffic growth and network failures.

You can do “what if” analyses (called scenarios in OPNET) on network designs, just as you can on spreadsheets with financial business models. However, instead of looking at “bottom line” financial numbers, you will be looking at how response times, latency (delays) and other network performance

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measures will change under different network design approaches.

To create a network simulation (called a project in OPNET), you specify the nodes (computers, switches, routers, etc.) in your network, the links between nodes, and the applications that will be running on the nodes.

In this lab you will learn to built a simple network with a few user clients, some swithces and servers. You will learn how to configure each device and run the simultations. You will also learn how to collect results and ananlyse the obtained resutls.

NOTE 2: Do not go and change anything in the process model. Your models will stop compiling

Lab Instructions

Step 1: Design and Configure the basic network

OPNET consists of projects and scenarios. Scenarios may contain different versions of the same network or models of different networks. A project consists of one or more network scenarios. In this lab, you will create 2 different scenarios comparing application performance with different connection speeds.

1. Click Start → OPNET modeler

2. You will see the license agreement – Accept it

3. You will now see the modeler.

4. To create a new project click on File → New.You will see the following dialog box.

5. Select Project and Press ok.

6. You project editor workspace will open now. Enter project name as LAB0 and change scenario name to “slow_scenario”


7. From the next dialog box, select “Create empty scenario” and press Next

8. From the next dialog box, select “Campus” and press Next

9. Don’t change the size, just press Next.


10. Don’t select any technology, just press Next.

11. The setup is complete. Press Finish

12. You will now be able to see the object palette and the Project workspace

13. Select and Ethernet Workstation for the object palette and put it on the workspace


14. Now construct the following network. Use 10BaseT links to connect the devices. Set appropriate names for the devices.

15. Now configure the applications and the profiles.


16. Now add the services to the server and add the profile to the client


17. Choose the statistics that you want to collect. Right click on the empty workspace and select Choose individual DES statistics. Choose the client HTTP, Server HTTP, IP from the Node Statistics and the point-to-point statistics from the Link Statistics


18. Now Run the Simulation. Do not change any simulation parameters. This may take some time. Press Close after the simulation completes.

Click on this icon to run the simulation:

19. Now check your results. To see you results click on DES → Results → View Results or you can do Right Click on the workspace → view results.

Answer the following questions:

Setp 1: In scenario 1

1. Copy the scenario 1 that you created.


2. Copy and paste the graph that you obtained for the average Object response time and page re-sponse time for Client 1. Why is the Page response time more than the object response time?

Answer: Object Response Time (sec) Specifies response time for each inlined object from the HTML pagePage Response Time (sec) Specifies time required to retrieve the entire page with all the con-tained inline objects. So page response time is more than object because it is comparatively larger than object.


3. Copy paste the graph for the load on the server, task processing time, traffic received and traffic sent. Explain the graphs keeping in mind the type of application used.

Answer: The graph below shows the load, task processing time, traffic sent, traffic received on the server which is http hence the amount of load going on the server, traffic received on the http server and traffic sent has been simulated on opnet.


4. Record the queuing delay and utilization of the link. Explain the graph (paste a copy). Why do you see two records of the utilization of the link? Why are they different?Answer There are two records of utilization because one is for switch to server when data is coming in and other when data is going out and both need to be different because both the cases the processed data is different and hence we see the variation in graphs


Step 2: Configure the Link to 100BaseT

In the previous scenario, we had use 10BaseT for the links. Now we have to create a new scenario.

1. Click on Scenarios → Duplicate Scenarios

2. Add the new name: Fast_Scenario

3. Now change the links to 100BaseT

4. Run the simulation and compare the results with the previous scenario. You can you DES → Re-sults → Compare Results

5. Answer questions 2, 3 and 4 from scenario 1 when you replace the link? Is there a need to re-place the link – explain? Answer : Yes there is a need to change it because we see a difference in the response time of the graphs.Ques2: Copy and paste the graph that you obtained for the average Object response time and page response time for Client 1. Why is the Page response time more than the object response time?Object Response Time

Page Response Time


Ques3: Copy paste the graph for the load on the server, task processing time, traffic received and traffic sent. Explain the graphs keeping in mind the type of application used.Load On Server


Task Processing Time

Traffic Received

Traffic Sent


Combined

Ques4: Record the queuing delay and utilization of the link. Explain the graph (paste a copy). Why do you see two records of the utilization of the link? Why are they different?

Queuing Delay


Utilization


Step 3: Extend the network

Add one more client and one more server. Configure the server as an Email server. Client 2 should access both email and web services. This will require creating a new profile which supports both services and assiging this profile to Client 2.

Create two scenarios again, for 10Base T and 100Base T. Compare the Web Response times and Email response times for the two scenarios.

6. Copy paste the graphs from scenario 3. Label the scenarios appropriately

7. Answer questions 2, 3 and 4 from scenario 1. Compare with the results that you obtained from scean-rio 1 and sceanrio 2

Ans For 100BaseT Link:.









Utlization (Switch to Client)


Utilization ( Switch to Server):


Queueing Delay

Switch to Server


Queueing Delay:

Switch to Client:


For 10Base T links:

Page Response and Object Response Time


For Email Response time:


Load on server:


Task Processing time:


Traffic received (Bytes/sec):


Traffic sent (bytes/sec):


Queuing Delay ():


Queuing Delay ():


Utilization ():


Utilization ():


There is a difference between this scenario and the above scenario as we get variations in the graph and variations are comparatively a bit more because addition of client and server changes the amount of load and traffic.


Documents

Opnet Assignment 1