Switched LANs And Network Design Anatomist Essay

The GEOGRAPHIC AREA Systems (LANs) can provide only a small geographic area and there's a limitation for the full total amount of hosts that may be attached to a single network. To be able to communicate between your hosts network devices like hubs and switches are used. Thus a set of LANs that are interconnected by switches will form switched LANs and this lab is focused on the performance evaluation of the switched LANs.


The main goal of this lab assignment is to compare and review the performance of turned local area networks (LANs) that are integrated through the hubs and switches. The performance study of various guidelines like throughput, amount of collisions, and wait of the network is performed through the simulations extracted from the project implementations and the questions are responded from the simulations.


The execution of the turned LANs is done through OPNET IT Master software. The software provided detail by detail procedures. Inside the first step, the network is established with the hub configuration having nodes from node_0 through node_15 and the hub is known as as HUB_1. The Ethernet connection 10BaseT, manages at 10Mbps and is employed to link between the 16 hosts present in the network. The network nodes are then separately configured for the traffic generation guidelines and packet generation parameters features. As the hub construction would send the packets received at its input to all or any the end result lines regardless of the destination the hub construction network design is really as shown below.

The second settings uses both the hub and the change. Here a switch is used between the two hubs named HUB_1 and HUB_2. Each hub is linked to 8 nodes and the connection is established through the Ethernet 10BaseT link. The primary difference between the hub and the swap is usually that the switch runs on the store and forwards mechanism. Thus it'll onward the packets received at its suggestions port to the required vacation spots and sometimes buffers because of the network traffic. The network construction for such a mixture of hub and move is detailed in the below simulation design.

The above two network configurations are analyzed for the characteristics packet generation and traffic generation parameters. Both of them are similar and the packet era occurred for every 100 seconds. The simulation of the configured network is run for each and every 2 minutes and the details are captured for further evaluation.


The simulation results for the configured systems are plainly depicted by the graphs. Fig 3 details the traffic delivered over the hub and the hub-switch combination. From the graph we can identify the amount of traffic directed across both configurations remained the same. Fig 4 shows the packets that are received at the destination for both configurations. Through the graph we can declare that the hub-switch settings is more efficient on the hub alone construction.

The analysis of that time period wait in Fig 5 gives a clear idea about the efficiency of hub-switch construction. The hub-switch settings had a hold off of 0. 020 secs constantly for a particular load and there is absolutely no such criterion for the hub only construction.

The collision matter in Fig 6 depicts that the collision count up for the hub exclusively is practically 2300 for a frequent timeframe and the truth with the hub and change combination is far less which matters to practically 900. Thus we can say from the graphs that the efficiency of hub and turn network construction is more when compared to the hub by itself network configuration.


Question 1: Explain why adding a transition makes the network perform better in terms of throughput and wait.

Answer: Through the simulation results it is apparent that a move performs well by dividing the network into smaller collision domains. Thus the throughput could be increased and also the switch provides the network bandwidth of 10 Mbps completely on each of the nodes and therefore the wait of the network is reduced effectively.

Question 2: We analyzed the collision matters of the hubs. Is it possible to review the collision count number of the "Switch"? Discuss your answer.

Answer: Yes. The collision count of a switch can be examined with the habit of the transition. The switch uses a store and frontward mechanism. Thus it also offers the capability of buffering the packets in times of network traffic. These major top features of the turn would permit the move to have no collision. Thus switches tend to be more preferred.

Question 3: Create two new scenarios. The first one is the same as the OnlyHub circumstance but replace the hub with a transition. The next new scenarios is equivalent to the HubAndSwitch situation but replace both hubs with two switches, take away the old turn, and connect the two switches you merely added together with a 10BaseT hyperlink. Compare the performance of the four scenarios in conditions of delay, throughput, and collision matter. Analyze the results. Note: To displace a hub with a switch, right-click on the hub and assign ethernet16_turn to its model attribute.

Answer: The results extracted from the simulation graphs would show the throughput and time hold off in different configurations. From Fig 7, it sometimes appears that hub and swap configuration gets the increase in throughput and the hub only settings has the least throughput on the list of four. Enough time delay between your four configurations is examined from the Fig 8. Here the two switches construction has a least time delay because the usage of switches would boost the delay in time. This is clear from the simulation graph as the time delay is just about about 0. 002 moments. The evaluation of collision matter is already reviewed in question 2. When two switches are being used by the property of the switches the collision count up would be zero. Thus switches are the best construction devices as compared to hubs.


Thus, the Switched LANs laboratory assignment gave an extremely clear perspective for the decision of network construction in a preferred location by learning the hub and switch basics. The simulation results were noticeable to verify the better efficiency of any switch than a hub. Hence, the marketing of network with a switch rather than a hub will produce cost efficiency.



In this laboratory we developed a company's network having 4 departments. Since it was a small network, we used LAN model. We used OPNET Expert to simulate the network design. After the design was done we assessed the outcome and tried out to excel the network by changing some of the hardware, such as using different servers for databases, data files and web vs. using one for all those three of them. We also compared the same network using low vs. high thickness cables. Thus, this laboratory is about the optimization of network.


The main goal of this laboratory was to show the learning of the fundamentals of network design. To be able to accomplishing this we took into consideration the users, services, and locations of the hosts.


To put into practice this network, we used OPNET Master as it is one of the greatest tools in Networking. It allows one to simulate the network with any mixtures of devices and protocols we have on the market. First, we created a clear task and added things: Application Configuration, Profile Settings, and a subnet as node_0, node_1 and subnet_0 respectively. Then, we configure services for applications, specifically: engineers, researchers, salespeople, and media users. Later, we configure the subnet. Then, we generate a 10-workstation superstar topology LAN. We do this for each and every of the four departments mentioned above. Now, we configure all the departments. Now, we configure all three machines based on different services needed for each and every followed by hooking up each division to the subnet.

Finally, we setup the network to check for reports about the global site and run the simulation to examine the results. Later, we keep the same setup as with Amount 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 reduced density cords with high density to observe distinctions. You now are you will be ready to observe the results and analyze the network.


In physique 4. 3 bellow, we noticed that the response time of the active network was higher than the easy network. Also, the machine stabilizes extremely swift set alongside the busy network.

From number 3, high denseness cables were very helpful in optimizing the results. With high denseness cables we get occupied network producing a response time as though it were a straightforward network and it stabilizes really fast too.

It was obvious that File server stabilizes faster than both the Database Server and the net Server. Second, Repository Server fluctuate minimal. It became clear that one server updating the three server has the most load, so that it CPU Usage is the most and it relatively higher than the net Server together.


Question 1: Review the result we obtained about the HTTP page response time. Pull together four other figures, of your choice, and rerun the simulation of the Simple and the busy network scenarios. Find the graphs that compare the gathered statistics. Comment on these results.

Answer: In the HTTP response time for the easy and busy networks, the simple network is symbolized in blue and the active network is symbolized in the color red. The contrast of both time wait would lead to a summary that the wait is a lot less in the easy network as compared to the occupied network.

We have considered four other situations for comparison and they're depicted in the graph as below

The first storyline shows the Ethernet delay time and from the shape we're able to notice obviously that the hold off in the occupied network is higher as compared to the easy network.

The next plot shows enough time delay comparisons of the TCP hold off. We could recognize that the TCP wait for the active network is fluctuating at first ata higher rate and then it subsides almost even but still at at an increased pace. Alternatively the easy network has a ver low flutuating primary time wait and then it has stabilized over time of energy.

The graph below represents the response time for the DB access and the comparison between the simple and active network shows a great deal of difference. The busy network is a lttle bit fluctuating at the initial stage and then it commences to a well balanced state. But nonetheless the wait is high over here. The easy network is having a quite steady time responde right from the start. This could be noticed from the graph below.

The response time for the DB Query is as shown below. In this particular scenario also the easy network has a quite steady time delay and incredibly small in comparison with the initial fluctuating time delay of the occupied network.

Question 2: Inside the Busy Network situation, study the utilization% of the CPUs in the servers (Right-click on each server and select Choose Individual Figures ? CPU ? Utilization).

Answer: The CPU utilization through the Busy Network Scenario for the webserver, repository server, and record server are as below

From the graphs above, it is evident that Data file server stabilizes a lot faster than both Repository Server and the Web Server. Second, Databases Server fluctuate the least if you go through the magnitude on the y-axis.

Question 3: Create a new situation as a duplicate of the Busy Network situation. Name the new situation Q3_OneServer. Replace the three servers with only 1 server that helps all required services. Research the usage% of that server's CPU. Compare this usage with the three CPU utilizations you obtained in the last question.

Answer: It is noticeable from the graph above that the one server replacing the three servers gets the maximum fill, so its CPU Utilization is the most and it somewhat higher than the Web Server in the last scenario. This is because the net server was using the most CPU amount of time in the previous occupied scenario.

Question 4: Create a new circumstance as a duplicate of the Busy Network scenario. Name the new circumstance Q4_FasterNetwork. Inside the Q4_FasterNetwork circumstance, replace all 100BaseT links in the network with 10Gbps Ethernet links and replace all 10BaseT links with 100BaseT links. Analyze how increasing the bandwidth of the links influences the performance of the network in the new circumstance (e. g. , compare the HTTP web page response time in the new situation recover of the Busy Network).

Answer: After making all the changes to the links, we have the following results:

From the results above, it is evident that network response time is a lot faster which it stabilizes really fast too. In other words, the Q4_FastNetwork is compatible to Simple Network rather than Busy Network only because we used high denseness cables.


In realization, we learned the fundamentals of creating a network, considering the users, services, and locations of the hosts. We discovered this by using OPNET tool which is great for simulating network systems. We also, learned that using high thickness cables will enhance the network greatly and may also convert the response time of a network to be so fast as if it were a simple network and it stabilizes the network extremely fast too. We also noticed that using separate servers for different activities, such as, Data source, files and web offers better performance of CPU usage. Thus, one should consider using high thickness cables and individual servers for Directories, files and Web to avoid overloading just one server.

Also We Can Offer!

Other services that we offer

If you don’t see the necessary subject, paper type, or topic in our list of available services and examples, don’t worry! We have a number of other academic disciplines to suit the needs of anyone who visits this website looking for help.

How to ...

We made your life easier with putting together a big number of articles and guidelines on how to plan and write different types of assignments (Essay, Research Paper, Dissertation etc)