Opnet lab 4 solutions
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This document summarizes an OPNET lab on network design. The lab involved designing a network for a small company with 4 departments. Different scenarios were modeled and compared, including using separate servers versus one server for all services. High density cables were found to optimize network performance. Using separate servers distributed the load better than one server handling all services. Overall, the lab demonstrated fundamentals of network design and how choices like infrastructure and server configuration impact performance.
Opnet lab 4 solutions
- 1. Lab# 4 Haidarnafia833@gmail.com Opnet Lab 4 Solutions NETWORK DESIGN Planning a Network with Different Users, Hosts, and Services Haider Nafaa Nseif ID:I201521051 9/1/2018 IRAQ
- 2. Lab# 4 Haidarnafia833@gmail.com OVERWIEW: In this lab we developed a company's network having 4 departments. Since it was a small network, we used LAN model. We used OPNET Guru to simulate the network design. Once the design was done we assessed the outcome and tried to excel the network by changing some of the hardware, such as using separate servers for database, files and web vs. using one for all three of them. We also compared the same network using low vs. high density cables. Thus, this lab is about the optimization of network. OBJECTIVE: The main goal of this lab was to show the learning of the fundamentals of network design. In order to doing this we took into account the users, services, and locations of the hosts. IMPLEMENTATION PROCEDURE: To implement this network, we used OPNET Guru as it is one of the greatest tools in Networking. It allows one to simulate the network with any combinations of devices and protocols we have available today. First, we created an empty project and added objects: Application Configuration, Profile Configuration, and a subnet as node_0, node_1 and subnet_0 respectively. Then, we configure services for applications, namely: engineers, researchers, salespeople, and multimedia users. Later, we configure the subnet. Then, we create a 10-workstation star topology LAN. We do this for each of the four departments stated above. Now, we configure all the departments. Now, we configure all three servers based on different services needed for each followed by connecting each department to the subnet.
- 3. Lab# 4 Haidarnafia833@gmail.com Finally, we setup the network to test for statistics about the global page and run the simulation to assess the results. Later, we keep the same setup as in Figure 1 above and change the background utilization to be 99 percent to create the Busy Network. And run the simulation again. Finally, we duplicate the Busy Network and replace the low density cables with high density to observe differences. Now you are you are ready to observe the results and analyze the network.
- 4. Lab# 4 Haidarnafia833@gmail.com OBSERVATION AND RESULTS ANLAYSIS: In figure 4.3 bellow, we observed that the response time of the busy network was much higher than the simple network. Also, the system stabilizes very quick compared to the busy network. From figure 3, high density cables were very helpful in optimizing the results. With high density cables we get busy network producing a response time as if it were a simple network and it stabilizes really fast too. It was apparent that File server stabilizes a lot faster than both the Database Server and the Web Server. Second, Database Server fluctuate the least. It became apparent that one server replacing the three server has the most load, so it CPU Utilization is the most and it somewhat higher than the Web Server alone.
- 5. Lab# 4 Haidarnafia833@gmail.com QUESTION AND ANSWERS: Question 1: Analyze the result we obtained regarding the HTTP page response time. Collect four other statistics, of your choice, and rerun the simulation of the Simple and the busy network scenarios. Get the graphs that compare the collected statistics. Comment on these results. Answer: From the HTTP response time for the simple and busy networks, the simple network is represented in blue and the busy network is represented in the color red. The comparison of the two time delay would result in a conclusion that the delay is much less in the simple network as compared to the busy network. We have considered four other scenarios for comparison and they are depicted in the graph as below: The first plot shows the Ethernet delay time and from the figure we could notice clearly that the delay in the busy network is higher as compared to the simple network.
- 6. Lab# 4 Haidarnafia833@gmail.com The next plot shows the time delay comparisons of the TCP delay. We could understand that the TCP delay for the busy network is fluctuating initially at a higher rate and then it subsides almost even but still at a higher pace. On the other hand the simple network has a very low fluctuating initial time delay and then it has stabilized after a period of time. The graph below represents the response time for the DB entry and the comparison between the simple and busy network shows a great deal of difference. The busy network is a bit fluctuating at the initial stage and then it commences to a stable state. But still the delay is high over here. The simple network is having a quite stable time responde from the beginning. This could be observed from the graph below. The response time for the DB Query is as shown below. In this scenario also the simple network has a quite stable time delay and very small when compared to the initial fluctuating time delay of the busy network.
- 7. Lab# 4 Haidarnafia833@gmail.com Question 2: In the Busy Network scenario, study the utilization% of the CPUs in the servers (Right-click on each server and select Choose Individual Statistics ? CPU ? Utilization). Answer: The CPU utilization during the Busy Network Scenario for the webserver, database server, and file server are as below: From the graphs above, it is obvious that File server stabilizes a lot faster than both the Database Server and the Web Server. Second, Database Server fluctuate the least if you look at the magnitude on the y-axis.
- 8. Lab# 4 Haidarnafia833@gmail.com Question 3: Create a new scenario as a duplicate of the Busy Network scenario. Name the new scenario Q3_OneServer. Replace the three servers with only one server that supports all required services. Study the utilization% of that server’s CPU. Compare this utilization with the three CPU utilizations you obtained in the previous question. Answer: It is apparent from the graph that the one server replacing the three servers has the maximum load, so its CPU Utilization is the most and it somewhat higher than the Web Server in the previous scenario. This is because the web server was using the most CPU time in the previous busy scenario. Question 4: Create a new scenario as a duplicate of the Busy Network scenario. Name the new scenario Q4_FasterNetwork. In the Q4_FasterNetwork scenario, replace all 100BaseT links in the network with 10Gbps Ethernet links and replace all 10BaseT links with 100BaseT links. Study how increasing the bandwidth of the links affects the performance of the network in the new scenario (e.g., compare the HTTP page response time in the new scenario with that of the Busy Network).
- 9. Lab# 4 Haidarnafia833@gmail.com Answer: After making all the changes to the links, we have the following results: From the results above, it is obvious that network response time is much faster and that it stabilizes really fast too. In other words, the Q4_FastNetwork is compatible to Simple Network instead of Busy Network only because we used high density cables.
- 10. Lab# 4 Haidarnafia833@gmail.com CONCLUSION: In conclusion, we learned the basics of designing a network, taking into consideration the users, services, and locations of the hosts. We learned this by using OPNET tool which is great for simulating network systems. We also, learned that using high density cables will optimize the network greatly and can even convert the response time of a network to be so fast as if it were a simple network and it stabilizes the network very fast too. We also noticed that using separate servers for different activities, such as, Database, files and web gives better performance of CPU utilization. Thus, one should consider using high density cables and separate servers for Databases, files and Web to avoid overloading just one server.