Monday, June 3, 2019
Firewall Effects on Network Performance | Evaluation
Firewall Effects on Network Performance EvaluationIn an age where our society relies so heavily on electronic communication, the contract for culture security is constantly increasing. Given the value and confidential nature of the development that exists on todays earningss, CIOs are finding that an investment in security is extremely beneficial. Without security, a company rout out suffer from theft or alteration of data, legal ramifications, and other issues that all result in monetary losses. The Best Damn Firewall volume PeriodCorporations are realizing the need to create and enforce an reading security insurance. As aresult, IT professionals are constantly being challenged to secure their vanes by installing firewalls that earmark more secure Cisco Security Specialists Guide to PIX Firewall.Firewalls are essential components in improving network security. Most firewalls are deployed at the edge of the network to reach legitimate traffic, and can be deployed in the cor e of the network to further supplement and protect the capability of the network and the application running everyplace the network to deliver required services to the end user. Firewalls cast off become increasingly complex, evolving from offering traditional firewall capabilities to protect networks, to offering application-aware processing of several cyberspace protocols.Brief literature reviewFirewalls are the first front line defense mechanism against intruders ,a firewall system can operate at five of the sevensome layers of the OSI reference model. However, most firewall systems operate at only quaternary layers the data link, network, transport, and, possibly, application layers. Based on the simplicity or complexity of a firewall reaping or solution, the number of layers covered varies. For example, a standard IP access control list (ACL) on a Cisco router functions at OSI Layer 3, and an wide IP ACL functions at Layers 3 and 4. cisco press cisco router firewall se curityFirewalls work by inspecting assorted fields in headers of the packet, finding the matching rule and doing the action stipulate in the rule. Common firewalls (and rules) examine at least IP addresses, next protocol type (TCP or UDP) and in case of TCP or UDP their various(prenominal) port numbers. That usually gives five different variables (source destination address, protocol, source destination port) to work with. Optimizing firewall performance. Performance depth psychology of the Linux firewall in a host. As example ,a firewall that operates at only Layers 3 or 4 can filter only on IP protocol information, IP addresses, and TCP or UDP port numbers it cannot filter on application information such as user au whencetication or commands that a user enters. Therefore, the more layers a firewall can process information from, the more granular it can be in its filtering process. cisco press cisco router firewall securityThere are many considerations that organizations shoul d include in their firewall selection and planning processes. Organizations need to determine which network areas need to be protected, and which types of firewall technologies forget be most effective for the types of traffic that require protection. Guidelines on Firewalls and Firewall indemnity. In addition, Incorporating a firewall into a network structure is likely to increase processing and even create bottlenecks Evaluation of Firewall Effects on Network Performance ,whereas Each rule that a firewall has to analyze results in spare processing overhead. This means that the more rules a firewall has, the longer it will take for the firewall to determine whether or not the packet in question may be given through. Firewalls Overview and Best Practices.As result Firewalls are one key factor in network performance. If they cant process their rules fast enough then the substantial network slows slash. Optimizing firewall performanceSome studies shows that the firewall is se nsitive to the number of rules, the type of filtering, and the transmission rate. The results of our first scenario demonstrate that for each type of filtering, latency increases linearly as the number of rules increase. Performance epitome of the Linux firewall in a hostScope and limitation of the studyThere are some points may represent the scope and limitation of the study, includingThis project focus on evaluating the effect of firewall performance using an OPNET Modeler network simulator and analyzing on different scenarios and to compare the performance collision when firewall employ.This project excessively focusing on effectuate of firewall filtering on network performance.In this study we are going to select special type of firewall application firewallThe number of workstation is limited which wont exceed cc nodes.The result will be collected is carnald on the simulation so may be this result will not be applicable in real hardware.Statement of the research problemTh is research reports on the evaluation of using firewall in three different scenarios, which can show the impact of applying the application firewall on the performance of the network. Therefore, the research addresses the following research problemHow can we make trade-off between the security and performance?Essentially I argue that in order to investigate the feasibility of exciteting the trade-off of using the firewall, its necessary to compare the result when the firewall applied in different scenario, it magnate be depends on the policy or function nodes.Research questionsTo address the research problem identified in the previous section, the following research questions have been designedWhat are banish aspects of firewall?What are positive aspects of combined security and performance?What are the effect of firewall in the link utilization?What are the effects of firewall in the Real time application?Research objectivesThe main objective of this research is to investigate the impact of firewall policy on the performance of the network.To identify negative aspects of firewall.To determine positive aspects of combined security and performance.To examine the effects of firewall in the link utilization.To identify the impact of firewall in real-time application.To compare the result from different scenario to estimate the effects of policy.Significance of the studyThe growing Demand for using firewall by the internet users and companies to provide more protection for them and the influence of apply firewall policy in the network performance gave the impetus for this study. To verify that we propose here three different scenarios,CNTs as the one of the components of MMIC transmission lines to enhance the electrical performance. This hearty offer some remarkable characteristics for microelectronics applications and their large kinetic inductance (skin effect), long mean free paths, high current carrying capability and high thermal conduction made them id eal candidates for RF/microwave applications as transmission lines.Research methodologyThe research methodology work will go through four microscope stages namely a priori stage, data analysis and design stage, lab stage, and evaluation stage.Theoretical stageThe objective of the theoretical stage is to constitute a theoretical frame to enable the success of the lab stage through that frame.Data analysis and design stageIn this stage, all related data obtained in the theoretical stage will be analyzed and then a selection process will be through in order to get the high quality CNT and the right design for CNT-based TLs to be able to accomplish the research questions through tax write-off and expo positive(predicate) process.Lab stageAt this stage, firstly, the offset parameters will be optimized by using chemical vapor deposition harvest-home method In order to produce large scale and well-aligned CNTs. Next, the characterization process will be through on the samples. SEM, F ESEM, and HRTEM techniques will be used to study the word structure of the samples. XRD and EDEX techniques are used to study the samples crystallographic structures and composition elements in the samples respectively. For electrical characterization, I-V and resistivity measurements using four point probes will be applied for low frequency. Lastly, in the implementation process, the determined high quality CNT will be used to fabricate transmission lines, and then RF characterization will be done using VNA at different frequencies.Evaluation stageThe experimental results are analyzed to evaluate the effectiveness of the new variables in order to get the best CNT for the TLs.Current StageFor device applications, the orientation of the CNT is in particular important. Therefore currently, the ontogenesis parameters are optimized by using chemical vapor deposition growth method and then, scanning electron microscopy (SEM) is used to study the morphology of the samples in order to g et large scale and well-aligned CNTs.The fabrication of CNTs on P-type silicon substrates size 1 cm by 1 cm were done using nickel (Ni) as gas pedal. The first process is to remove any impurity and oxidization on the Si substrate surface. The substrate will go through stages of cleaning process, starting with acetone, methanol and then rinsed with deionized water to remove organic contaminants and particles. Then, the Si wafer was cleaned by hydrogen gas to remove natural oxide. Next, a thin Ni film was deposited on a substrate as catalyst using Electron-Beam evaporator and the substrate was placed on alumina boat sooner placed inside a double-heater TCVD. The first heater was set at gramC to decompose methane, while the second was set at 800 to 1000C for pre-treatment of the catalytic film. As A. Awang Teh et. al. proposed 41 a precursor of ammonia and methanol solution at ratios of 58 was used to enhance the growth of CNT in methane ambient. The second heater was first switched in flowing Argon at 100 sccm. When the temperature of the second heater reached setting point and stayed stable, first heater was then switched on and methane gas was flown at flow rate of 10-50 sccm. The total growth time of the CNTs varied from 30 to 3 hours. Finally, methane gas was turned off and the furnaces were cooled down to room temperature in flowing Argon at 100 sccm to avoid carbon oxidation. After fabrication is completed, The CNT morphology was examined using SEM.Figures 1- 6 show the growth of CNTs on Si substrate using Ni with different thicknesses and subjected to methane ambient at 850 oC for 2 hours. One of the first things to note is that the catalyst thickness affects the diameter and density of the CNT. The catalyst film thicker, the larger diameter and more density CNT we can get. Also, it can be seen clearly this relationship from the SEM results shown in fig.11 to 14. Furthermore, from the SEM image shown in figure 4 the least nickel or carbon nanoparticles protrude from the nanotubes was observed. These conductive nanoparticles cause electrical shorts between interconnects for device fabrication. For this reason we can consider that the optimum nickel catalyst thickness in our case is 10 nm. A final point to note is that there is no CNT at all in figure 1. It means that the catalyst film thickness is very thin and after recombination the size of catalyst nanoparticles is too small to synthesis CNTs.Another key parameter to affect CNT growth is temperature gradient. As we can see from the SEM results shown in figures 7-20, by controlling the growth temperature we can increase the growth efficiency and purity. At reaction temperature 900C, the growth of clean CNTs was observed. However, no CNTs were formed when the growth temperature exceeded 900C. Instead, amorphous carbon was observed on the surface of the substrate.Besides catalyst and temperature gradient, carbon source flow rate likewise plays an important role in the CNT growth. It can be stand out from experimental results shown in figures 21 to 28 that a higher flow rate will increase the decomposition rate, and consequently the growth rate of CNT. However, when the flow rate of Ni was 10 sccm there is not enough reactant to react with the catalyst and just catalyst nanoparticles were observed.The gas flow rate affects not only CNT density but also nanotubes diameter. The higher gas flow rate, the larger diameter of nanotubes will grow. However, after a critical point, increasing the flow will change the carbon mathematical product from CNTs to carbon nano-fibers (CNFs), as it was observed from the result.The last growth parameter we have optimized is syntheses time. From experimental results shown in figures 29 to 32 we can find the relationship between the syntheses time and the length on nanotubes. Longer synthesis time with longer catalyst lifetime, longer CNT we can get.More optimization and characterizations must be done on the samples in order to get well-aligned and density MWCNT, before transmission line fabrication.Preview of the thesisThis thesis is organized into five chapters.Chapter One serves as an introduction to this study, providing the theoretical framework, research objectives and significance of the present study. It also offers a brief overview of the methodology that is employed. Definitions and delimitations that map out the boundaries for the present study are also outlined.Chapter Two provides the literature review for this study and serves to develop key issues related to the theoretical framework.The third chapter is on methodology. This study approaches the issues of fabrication, simulation and modulation.The fourth chapter reports the results of the content analysis and discusses the findings.The fifth chapter reviews the research questions and summarizes the thesis. This chapter also provides suggestions for future research.Network Security is one of the most important fields dealing with the Interne t. The ability to access and transfer information in a few seconds allows the government, companies, educational institutions, and individuals to accelerate the decision process or simply be informed. However, information can be very invaluable and there is a need for better and faster security systems to protect information and networks.Therefore, it is best to limit the number of rules to no more than 30-50. However, for best performance, slight than 25 rules are recommended. Also, firewalls process their rule base from the top down. As soon as the firewall finds a rule that applies to a particular packet, the rule is applied and the packet is processed (either allowed to continue or dropped). It is recommended that the most important and most utilized rules should be at the top of the rule list. This prevents the firewall from having to process through a number of rarely used rules to finally get to rules that apply to the majority of the network traffic. Determining the correc t order of rules for a particular implementation is an current process. Initially, there is a significant amount of testing and trial-and-error involved in determining the correct order that the rules should be in. Also, the rule base should be reviewed periodically to see if the organizations requirements or network usage has changed that would require the reordering of existing rules as well as adding or removing rules. Finally, one should make sure to keep the number of domain objects in the rule base to a minimum, and also make sure that these objects are kept towards the bottom of the rule base list.Firewalls Overview and Best PracticesThere are many aspects to firewall management. For example, choosing the type or types of firewalls to deploy and their positions within the network can significantly affect the security policies that the firewalls can enforce. Policy rules may need to be updated as the organizations requirements change, such as when new applications or hosts a re implemented within the network. Firewall component performance also needfully to be monitored to enable potential resource issues to be identified and addressed before components become overwhelmed. Logs and alerts should also be continuously monitored to identify threats-both successful and unsuccessful. Firewall rulesets and policies should be managed by a formal change management control process because of their potential to impact security and business operations, with ruleset reviews or tests performed periodically to ensure go along compliance with the organizations policies. Firewall software should be patched as vendors provide updates to address vulnerabilities. Guidelines on Firewalls and Firewall PolicyThe firewall can become a bottleneck. All network traffic that passes between the Internet and the DMZ, the DMZ and the private network, and potentially, the Internet and the private network, must be inspected by the firewall. This can result in the firewall becoming a bottleneck and reducing the performance between the network and the Internet.
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