Hybrid car Free Essays

Facts about Hybrid Cars: Some important facts about hybrid cars:- Hybrid vehicles are a practical solution to the rising greenhouse gas levels and may still be some time till these cars are introduced into the market. Auto Makers like Honda and Toyota have taken initiatives to improve on the existing Hybrid technology by inventing cleaner engines that also give more mileage. A Hybrid vehicle is one which uses an electric motor to provide additional power along with the conventional internal combustion engine. We will write a custom essay sample on Hybrid car or any similar topic only for you Order Now They have a special mechanism that is capable of recharging the batteries without being plugged in. They can also be charged by the gas-engine if need be. As a result, the gas engines can be a little smaller as there is an additional power supply for its aid. The advantage is that the gasoline engine can then be quite small, since power is obtained from not one but two sources. When the car comes to a sustained stop, the gas engine shuts down saving fuel. When the car is ready to accelerate, the electric motor kicks in till the time the gasoline engine can resume on its Job. Hybrid Subs may be the alternative to those gas-guzzling, pocket- ripping Subs which could manage very little mileage. EPA mileage estimates about 33 MPEG as city/highway average. The Toyota Pries is estimated to give an average of 55 MPEG. Apparently, it has a better mileage in city conditions rather than the highway. That’s because the battery pack comes into use more frequently in city conditions than on the highway. Advantages of Hybrid car: Hybrids combine clean energy of the electrical motor with the power of the gas- powered engine which results into lower emissions and better mileage. Thanks to the ever improving technology, hybrids perform at par with the normal gas-powered vehicles, if not better. Hybrids are reliable and comfortable as any traditional car ND they have a tax benefits(only till 2006). There are purchase incentives for Hybrid vehicle owners (varies by state). Hybrids are much cleaner cars than normal vehicles with lesser CO and other greenhouse gas emissions. Hybrids provide a better mileage. The future for hybrids looks bright with rapid developments in hybrid technol ogy to improve engine efficiency. Due to the Regenerative Braking technology, the batteries need not be charged by an external source. Disadvantages of Hybrid Cars: Hybrid cars, though useful, have some disadvantages. The point to be noted here is that the advantages far exceed the disadvantages. High cost: hybrids cost anywhere from $2,000 to $5,000 more their non-Hybrid versions. More weight due to battery packs. Some states charge additional fees for registration. In the event of an unfortunate accident, there is a risk of exposure to high voltage wires. They have a complicated system which needs to be taken care of by experienced mechanics only. Spare parts maybe hard to find and may be costly. Usually, hybrids have a lower acceleration than that their normal counterparts. The hybrid car can be considered to be the car of the millennium. This is a very environment friendly car that hardly produces any combustion at all. This is a car that basically runs on two sources of energy; one being a fuel, and another a battery. With the presence of two sources of energy to the hybrid car, there is obviously a lower requirement of fuel in the car. This is because most of the driving is managed with the energy the battery provides. The battery provides sufficient energy for the driver to use the car for its normal uses of transportation. How to cite Hybrid car, Papers

Information technology and profitability - MyAssignmenthelp.com

Question: Discuss about Information technology and profitability. Answer: Introduction In the modern times it has become necessary for the firms to take use of advanced technology. As information and technology has not only fasten the speed of operation but it has also enhanced the efficiency of the firms (Rai Tang, 2013). IT is being utilised in various fields of business. It has become essential for the companies to use IT systems that helps in making work process easier. Customised IT systems for various industries has helped firm in making their operational procedures easier and efficient. Every department within an organisation is somehow interconnected with information technology. This has empowered management to have control over the operations of the firm while sitting far away from their workplace. This report highlights the ways in which IT has affected the business in positive and negative senses. It also underlines the empowerment that is given by advanced software and hardware to various businesses. Use of IT in business This is the Era of technology which has forced companies to make use of IT systems for their operations (Venkatesh, Thong and Xu, 2012). There are many kinds of systems that are available for operations in various fields of business. Some of the most widely used technologies in various operations are as possible. Marketing: Todays marketing has shifted from traditional ways to the digital mediums. It has made the processes simpler and has a potential of reaching to larger sections of the society (Wu, Straub and Liang, 2015). Use of websites and apps has given direct contact with consumers which help them in showcasing various aspects of the products to consumers and hence increasing sale. Apart from this it is also to be understood that use of modern software and social media sites reduces the overall cost of operation as well as it gives the larger view of the market. Data management: It has become essential for the firms to manage its data. Use of technology in this regard has reduced the complexity of the problems (Tanriverdi and Uysal, 2011). Many Multinational companies have their operational units in various parts of the world and hence it has become necessary for them to have centralised data storage and access system. Cloud software provides excellent solution in tis regards. Decision making: Various software are available with the firm which helps them in making quick decisions. These software evaluate the data that is stored by the company from their operations in past. This helps them in understanding the scenario and taking decisions accordingly. Sale: Companies are taking use of various websites like their own site or some other e-commerce website for selling their products (Business 2 Community, 2018). This has reduced the efforts of employees as multiple products can be made available to the consumers and they can select as per their choice. This helps company in enhancing their sale as more options gets available to potential consumers as per their demand. Manufacturing: There are several kinds of manufacturing processes in which IT is being used. One of the most significant roles of IT is in automation which helps them in performing operations without excess manual interventions. IT software helps firm in detecting any flaws as well as performing operations as per the requirement without delay and with an ultimate accuracy. Monitoring: IT systems have helped companies in monitoring various processes like performance management system. This helps managers in understanding complexity of the work as well as finding things that are actually reducing the efficiency of the firm and making changes in them so as to maintain the efficiency of the firm ( J, 2018). There are many software that are available with the firm which helps in checking any kinds of deviations if occur in daily processes. Designing: IT systems also helps in designing of the whole process as it measures all the complexities that is present in the working process and acts accordingly to design various products. This is done by the analysing the demands and trends of the market as well as the quality and quantity of resources that is available with the firm. Transaction processing systems: This is a system that is extremely beneficial for the accounts department as all the transaction between consumers and firm is done through this system. This helps in maintaining the records of the total sale all over the world as well as reducing any kind of discrepancies in accounting. Market research: It has become essential for the firm to analyse the marketing environment that is present around the company. For this purpose market research is being conducted. This helps in understanding the trends and demands of the market which is beneficial for making decisions in a better way which will give them edge over the other rivals. Benefits of using IT in business There are several kinds of benefits of using IT in business. Some of the most effective use of IT in business is as follows: Efficiency: These systems are highly efficient and are capable of resolving many kinds of problems (Otim, Dow, Grover and Wong, 2012). They are accurate and hence they provide effective solutions to the issues that arise in day to day operations. There are many kinds of checking software that are present which helps in any kinds of deviations that occur in the processes. Speed: All these IT technologies not only provide efficiency but also enhance the speed of operations. There are faster algorithms available for IT software which helps in enhancing the overall speed of procedures that are operated in various departments of the firm. This also ensures timely delivery of the products to consumers which is essential factor for maintaining employee satisfaction. Reduction in errors: Since this is a competitive era of business and hence it has become essential for the firm to have higher focus on reducing errors in production of products and services. IT systems are very beneficial in this regard as they are highly accurate and show the details immediately in case any discrepancies occur in the processes. This helps in maintaining the quality of products as they have promised to their customers. Issues in use of IT within business While there are larger numbers of benefits that are associated with the use of IT systems, there are several kinds of issues that are present in the use of IT systems. These issues reduce the performance of the firm as well as pose a greater threat. This can lead to failure of business which is not affordable in the present competitive environment. Some of the prominent issues that are present in the use of IT in business are as follows: Security: Threat of security is one of the biggest issues that are present in the modern day business while taking use of IT systems (Mithas, Tafti, Bardhan and Goh, 2012).Various cybercrimes have been noticed in the past which has led to huge loss for the company. These security breaches are extremely harmful for the company as the hacker intends to steal many kinds of information related to the business which can result in strategic failure. It is essential for the firms to take use of firewalls so as to ensure that there is no easy injection of corrupted program inside the system. These security breaches can be by internal or by external sources. Privacy: There are many kinds of private data that are available with the company and are stored in information system. These data are extremely crucial and if they get in some others hand, they can utilise them for their personal benefit. Loss to such important data can lead to strategic failure and giving edge to other rivals. Passwords or some kind of authentications can help company in securing data since it prevents from any kind of unauthorised access. High cost: These technological advancements are of higher cost and the changes in the technology are faster and hence company has to invest a lot. It is estimated that in every six months technology in the industry gets doubled which enhances the need of the firms to upgrade their technology. This requires a whole lot of money which ultimately reduces the overall revenue of the firm. Maintenance: These systems need regular maintenance and if not properly handled then it may produce outcomes that are undesirable. It is essential for the firm to keep a system or a group of workers who are responsible for maintaining the information system. These systems are complex hence considerable amount of knowledge is required for maintaining the systems. Ways to resolve these issues Use of malwares: This helps in reducing the amount of attacks through various sources. They restrict other infectious viruses to enter into the system. But it is essential that they regularly upgrade this software so as to maintain the protection against such software. Use of authentication password: It is important to maintain the privacy and hence it is essential to take use of authentication system like password protection system or OTP. These are highly helpful in protecting effective data. Maintenance: It is essential that company gives timely training to the employees so that they can maintain the information system in a better way. It helps in maintaining the standards according to industry which helps in making competitive edge over the others. Conclusion From the above based report it can be concluded that information and technology is highly beneficial for the business as it enhances the efficiency of the work as well as maintain the quality of operations. Information systems enhance the speed of operations and hence help in enhancing consumer satisfaction which is necessary for the firm. There are several issues that are present in the use if IT. It is crucial for the firm to look at all these issues so as to maintain their quality. One of the biggest problem that companies faces while using IT technologies is the problem of maintaining the quality of the whole information system. For this purpose it is important that firm train their employees on regular basis. Processes like marketing, sales, transactions, decision making process and data management has become easier and hence has facilitated management in making changes as per the requirement. Reference Business 2 Community, 2018. [Online]. Available at: https://www.business2community.com/tech-gadgets/importance-information-technology-business-today-01393380. [Accessed on: 25th January 2018]. Cichetti. J, 2018. [Online]. Role of Information Technology in Business. Available at: https://bizfluent.com/facts-5977213-role-information-technology-business.html. [Accessed on: 25th January 2018]. Mithas, S., Tafti, A.R., Bardhan, I. and Goh, J.M., 2012. Information technology and firm profitability: mechanisms and empirical evidence. Otim, S., Dow, K.E., Grover, V. and Wong, J.A., 2012. The impact of information technology investments on downside risk of the firm: alternative measurement of the business value of IT.Journal of Management Information Systems,29(1), pp.159-194. Rai, A., Tang, X. 2013. Research commentaryinformation technology-enabled business models: a conceptual framework and a coevolution perspective for future research.Information Systems Research,25(1), 1-14. Tanriverdi, H. and Uysal, V.B., 2011. Cross-business information technology integration and acquirer value creation in corporate mergers and acquisitions.Information Systems Research,22(4), pp.703-720. Venkatesh, V., Thong, J.Y. and Xu, X., 2012. Consumer acceptance and use of information technology: extending the unified theory of acceptance and use of technology. Wu, S.P.J., Straub, D.W. and Liang, T.P., 2015. How information technology governance mechanisms and strategic alignment influence organizational performance: Insights from a matched survey of business and it managers.Mis Quarterly,39(2), pp.497-518.

Antitrust practices Essay Example

Antitrust practices Essay Example Antitrust practices Essay Antitrust practices Essay Antimonopoly patterns are patterns carried on by concerns that end up destructing perfect competition in the market. Antitrust Torahs are Torahs prepared to seek and advance healthy market competition by forestalling anti-competitive patterns by companies. Some of the illegal patterns that constitute to antimonopoly behaviour include corporate amalgamations. monopolies and monetary value repair confederacies ( Bailey. 2010 ) . The Clayton Act of 1914 was passed by the U. S Congress. It was an antimonopoly jurisprudence that was amended to halt and forestall patterns that led to unhealthy competition in the market. The Clayton Act was amended in order to complement an earlier version of the antimonopoly jurisprudence referred to as the Sherman antimonopoly Act of 1980. This was a federal jurisprudence that sought to forestall patterns that were harmful to consumers such as trusts. monopolies and other unjust concern patterns ( California Association of REALTORS. 2005 ) . Google Company One of the recent houses to be investigated for antimonopoly behaviour is Google Company that leads the online seeking industry. Harmonizing to Weiss ( 2014 ) . the house late was being investigated by Competition Commission of India ( CCI ) for claims that it abused its laterality in the on-line hunt engine industry by chiefly advancing its ain services over those of its challengers. This ground is considered to make unhealthy competition in the concern as the hunt engine company dominates its challengers in what is considered about a monopolistic market. Antimonopoly behaviour brings about both monetary and non-pecuniary costs. Since it amendss healthy competition in the market. monopolies can ensue and this has inauspicious effects to the monetary values of trade goods. The merchandises end up going dearly-won and expensive for the clients and. hence. impacting the society negatively ( Bailey. 2010 ) . On the other manus. antimonopoly behaviour leads to the end product of merchand ises falling below the market competitory degree and this is chiefly witnessed in monopolistic markets. Then once more. the antimonopoly patterns can be dearly-won for any company that has engaged in them since if probes prove that the company is guilty of the said Acts of the Apostless so heavy punishments can be imposed on them. Furthermore. this can destroy the repute of any company and. hence. stoping up losing its clients ( Bailey. 2010 ) . Monopolies and Oligopolies Monopolies and oligopolies are non ever good for the society. Their presence in any market merely means they have all the power to command the monetary values of their merchandises and services. This is non favourable to the clients since monetary values can ever travel up any clip particularly when the demand for certain trade goods is high. One good illustration of an oligopoly is the Coca Cola and Pepsi Companies. These are the world’s largest drink companies and demand for their merchandises is neer diminishing. However. these two companies represent a market with few providers while the consumers are many. They have all the power to order their products’ monetary values and the consumers have no power whatsoever ( Hovenkamp. 2011 ) . On the other manus. some authorities monopolies can be considered good to the members of the society. Many authoritiess in the current universe control the production and supply of electricity and other signifiers of energy. This is ut ile because the authoritiess aim at supplying such services to the citizens at low-cost monetary values and across the states. It is the duty of the authorities to heighten substructure development in the state and. hence. running such sectors of the economic system can be good to consumers. Decision In decision. it is of import to indicate out that antimonopoly patterns are unwanted behaviours since they destroy healthy competition among concerns. However. the jurisprudence is rigorous on companies that engage in these patterns and heavy punishments can be imposed on them. Antimonopoly patterns include monetary value repair. corporate amalgamations and creative activity of monopolies ( Reeves. 2010 ) .

Demostration Speech Essay Example

Demostration Speech Essay Example Demostration Speech Essay Demostration Speech Essay Grade: 95Instructor: Dr. Hayes Cynthia Horne Date: 9-25-2012 Topic: How to Check Your Blood Pressure Type: Demonstration Speech Mode: Memorized Introduction: I asked several questions to get the attention of my audience. This speech was a chance for me to share steps and experience on checking your blood pressure only takes 30 seconds. The steps were clearly stated, first choose the right equipment, second, stabled patient and third the right size blood pressure cuff. Blood pressure issues can strike at any age. The chaos, confusion and disorder in life will still be there. Keeping your pressures check will ensure you not having a heart attack or stroke. I spoke of having to check my blood pressure on regular basis. These easy steps are how I keep my doctor informed on the high and low of my pressure on a weekly basis. Body: My thoughts were organized logically. The main points were clearly explained. I took the listeners systematically step by step; bring in a short YouTube video of two ways on how to check your blood pressure manually by using the arm cuff or using a wrist cuff. I demonstrated this on a live patient. I included a little comedy build up to make my patient feel more relaxed. I wanted to get the best effect as possible. A source was cited as stated in the video, normal pressure is 120/80. The three steps I used to show how to check your blood pressure was supported in my speech. The evidence was clear and current. Conclusion: I have been battling high blood pressure for a few years now. I was on my way to having a stroke. Thankfully it was caught in time. It is a frightening experience that will challenge who you are, what is genuinely important to you and what your life is all about. I suggested to my audience to take The American Red Cross vital signs course that lasts about 2 or 3 hours. It is easy to take your blood pressure. It only takes 30 seconds. I adapted to my listeners feedback. My story received maximum impact. Other: I took a couple of slow deep breaths before I started. I focus in on my audience. Instead of looking down while doing my speech I look around the room making eye contact with everyone. I remembered that they are individual people, they are my classmates. I worked on the introduction so my speech will get off to a good start. I use video to create interest, draw attention away from me. My voice was not as shaky; therefor my tone of voice was smooth. I used my arm and hands to help tell my story effectively and drive home my main point. Materials List Omron Automatic Blood Pressure with cuff Live patient YouTube video Brochures Comments: Evaluations from my peers was on a grading scale from 1 to 5, with 5 being the strongest. I received a majority score of 5 strong points for organization, content, and delivery.

Illegal immigration Essay Example | Topics and Well Written Essays - 1500 words

Illegal immigration - Essay Example The end of the Civil War grew the desire to restrict immigration of specific groups to the United States. In 1875, the first statute was passed to restrict immigration which was barring prostitutes and convicts from admission (Nadadur, 2010). Various laws were enacted some to curb the issue of illegal immigration and others to ensure that regardless of their situation the immigrants are not subjected to any discrimination or unfair treatment. Undocumented people go through a lot of discriminations in the United States. Institutions that have been set up by the government are sometimes seen to be the perpetuators of these kinds of injustices (Obama, 2015). From the health sector, education, finance and even housing, they are seen to discriminate against the undocumented regardless of these areas handling the basic needs of any human being. Although these people access the United States without all the required documentation, they deserve to be respected and be treated as human beings. On the health sector, the undocumented also face discrimination. Disease breakouts are sometimes among the reasons why people migrate from their country to the United States. The migration is usually in search of a better health environment but the reception they get at the health facilities is not as they expect. The health insurance and policies available have not put them into consideration making access to health facilities difficult (Rhodes et al., 2015). Yet, access to health services constitutes the main determinant of the quality of life for all human beings. The employment world in the United States is another key area where the undocumented face discrimination. Most of the undocumented are people who come to the United States in search of a better job. Upon their arrival, they may have the qualifications needed to perform a particular task but an American will be given the priority. Once immigrants

BUS303 MODULE 2 LP Essay Example | Topics and Well Written Essays - 500 words

BUS303 MODULE 2 LP - Essay Example I actually commend the University for according students with the opportunity to make partial payments through accomplishing a Promissory Note form, which is to be secured from the Dean’s office prior to major examinations. Since my financial sources were not enough, I secured the form and lined up at the Cashier to make a partial payment. After about 30 minutes of queuing, the system experienced technical difficulties and those in line were told to either wait, try to pay through an authorized bank, or return the next day. The follow day, I directly went to the cashier; and true to her word, accepted my partial payment. I proceeded to the registrar to validate the payment and secure my examination permit, only to be told that the Promissory Note (PN) needed to be signed first at the Dean’s office. When I went to the Dean’s office, the line of students securing the signature on their respective PNs was longer than the eyes could see. After a patient wait and when one’s turn was due, the authorized signatory informed me that I needed to pay an additional $xxx amount; otherwise, I would not be given an exam permit despite the amount that I already paid. I had to go back to the Cashier, have the PN signed, return to the registrar and finally secure the exam permit. It would have been so much easier to have communicated all the payment protocols during orientation; or to have a flowchart of procedures posted near the Cashier and Accounting Offices. I hereby enjoin University personnel in charge of creating policies and procedures to publish payment protocols and avoid students queuing and being referred back to departments to secure signatures or make additional payments, which are fairly easy to comply with explicitly disseminated guidelines. This would likewise facilitate payment and collection and avoid unnecessary returns. Hoping for your immediate action in this regard. In writing the persuasive memo, the guidelines in writing persuasive

The Media Access Delay Information Technology Essay

The Media Access Delay Information Technology Essay OPNET Modeller is the network development software. OPNET permits design and learn communication networks, devices, protocols, and application. OPNETs object-oriented modelling stylishness and graphical user interface (GUI) let easy of developing models from the real world network, hardware devices, and protocols. Modeller supports all major network forms and technologies, permitting you to design and test various situations. (Opnet) Introduction I have deliberated various Medium Access Control (MAC) protocols for Wireless local Area (WLAN) Networks. To choose the best one surrounded by the existing protocols, it is necessary to have a network model scenario and some performance metrics on the basis of which they can be assessed. In this paper, various metrics for comparing the performance of MAC protocols and a network model to carry out simulation is discussed. At the end of this chapter, results obtained from the simulation in the form of graphs will be presented. DCF EDCF Metrics Picking the correct metrics or parameters in the evaluation of the QoS (Quality of Service) mechanisms is vital to the result and rationality of the evaluation. The metrics used are Throughput, Access Delay, and End to End Delay in case of real-time multimedia traffic like VoIP, Video streaming (Video conferencing), response time in case of Telnet or Remote Login; type applications which cannot tolerate delay and loss of data. Retransmission Attempts in case a station does not get a chance due to internal collision. The following list below is the item of metrics used: Throughput The Throughput for different priority levels shows how well the QoS schemes can provide service differentiation between the various priorities. The Throughput of all stations shows the utilization of the wireless medium. Wireless bandwidth is a scarce resource, so efficient use of it is vital. Media Access Delay We measure access delay as the time from when the data reaches the MAC layer until it is successfully transmitted out on the wireless medium. The reason for studying average access delay is that many real-time applications have a maximum tolerable delay, after which the data will be useless. Therefore, it is important to provide low delay for real-time flows. Retransmission Attempts Total number of Retransmission Attempts by all Wireless Local Area Network MACs in the network until either packet is successfully transmitted or it is discarded as a result of reaching short or long retry limit. For 802.11e-capable MACs, the Retransmission Attempt counts recorded under this statistic also include retry count increments due to internal collisions. This factor plays important role in Performance of WLAN. Data Dropped Data Dropped due to unavailability of access to medium. This factor largely affects the reliability of WLAN. Simulation Scenario Creating a simulation scenario that is corresponding to real world scenario is the first step of simulation. In this simulation, the wireless topology consisted of several wireless stations and one base station in the wireless LAN. The base station was connected to a wired node (Figure 2.1) which serves as a sink for the flows from the wireless domain. All wireless stations are located such that every station is able to detect a transmission from any other station, and there is no mobility in the system. This means our results will not be impacted by mobility and phenomenon such as the hidden node problem. Figure 2.1 Wi-Fi network models The simulation experiments are carried out using OPNET Simulator version 9.1 on Windows XP SP3. For this simulation, a data rate of 11 Mbps is chosen. Various MAC and PHY (Physical Layer of OSI) parameter values used in our experiment are according to IEEE 802.11e default values given in Table 2.1. We have run the simulation for 5 minutes for each scenario, and then compared the results obtained from them. Figure 2.1 shows a network model for the experiment. Table 2.1: MAC and PHY parameter values used in Experiment ATTRIBUTE VALUE Physical Characteristics Direct Sequence Data Rate (bps) 11 Mbps Transmit Power (W) 0.005 Buffer Size (bits) 256000 BSS Identifier Auto Assigned Channel settings Auto Assigned Roaming Capability Disabled AP Beacon Interval (secs) 0.02 Large Packet Processing Drop Simulation Method To compare the performance of DCF (Distributed Coordination Function) and EDCF (Enhanced Distributed Coordination Function) two scenarios were created; medium access in first scenario was supported by DCF and in second, EDCF protocol was used at the MAC layer. Network environment factors which were used as a benchmark configured same for both scenarios. Detailed specifications are given in the Table 2.1 showing the MAC and PHY parameters used in experiment. The performance evaluation is done by simulating both scenarios one by one in OPNET simulator and then comparing the graphs obtained. Results After choosing metrics, the simulation is done for 5 minutes for a scenario. Then results were gathered. Analysis of EDCF In case of EDCF, all four traffic classes were fed into the MAC layer from higher layer, which are corresponding to AC (0), AC (1), AC (2) and AC (3) respectively to check how efficient the new protocol is to provide service differentiation required for real time application. (Note that DCF does not support service differentiation, so no provision of Access category). For this, in the application profile of scenario (for EDCF protocol) different application was configured for different access category. Details are shown in the Table 4.1. Table 4.1 Access Category corresponding to an application ACCESS CATEGORY APPLICATION CONFIGURED DESIGNATION AC(0) HTTP (LIGHT) BACKGROUND AC(1) REMOTE LOGIN (HEAVY) EXCELLENT EFFORT AC(2) VIDEO CONFERENCING INTERACTIVE MULTIMEDIA AC(3) VOIP INTERACTIVE VOICE In the profile configuration, a profile for clients was configured that uses all the four applications. In simulation scenario, 15 stations were configured to use these services randomly. In the simulation, we assumed that each traffic class has the equal portion of the total data traffic in terms of the average number of packets generated per unit time. The results obtained are as follows: Throughput of Different Access Categories Figure 4.2 Throughputs of Different Access Categories It is observed from figure 4.2 that the Throughput of Access category 3 is way high than the Access category 0 and 1. Throughput for Access category 2 lies in between 3 and 1. It means that Throughput for applications like Voice over IP and Video conferencing, EDCF provides maximum Throughput by providing them more priority over the other services like simple HTTP. Media Access Delay for Different Access Categories Figure 4.3 Wireless LAN Media Access Delay It is observed from figure 4.3 that the Media Access Delay for Access category 3 is at minimum among all Access categories. Media Access Delay for Access category 2 is just 3 to 4 seconds more than AC (3). It means that the medium is assigned to the application according to the priority. Thus, EDCF provides lesser Medium Access Delay for real-time applications. Comparative Analysis of DCF and EDCF Next step is to check the performance of both protocols in terms of Throughput, Media Access Delay, Retransmission Attempts and Data Dropped. These four metrics are determining factors in terms of overall performance of both the protocols. Throughput Figure 4.4 Throughput of DCF vs. EDCF It is observed from figure 4.4 that in the first 30 seconds of simulation, Throughput of both DCF and EDCF is high, but then after that, it decreases with time and stabilizes for both protocols. Throughput in first 30 seconds is high due to less number of Retransmission Attempts (less number of backoffs). From Graph analysis, one fact is clearly visible, that curve of DCF is marginally higher than that of EDCF. We can conclude that DCFs overall Throughput is somewhat more than the EDCF. Retransmission Attempts Figure 4.5 Retransmission Attempts of DCF vs. EDCF It is observed from figure 4.5 that in the first 30 seconds of simulation, Retransmission Attempts for both DCF and EDCF are less, but then after that, it decreases with time and stabilizes for both protocols. Retransmission Attempts in first 30 seconds are less due to less number of backoffs assigned to wireless stations. There is a small noticeable difference between curves of Retransmission Attempts of DCF and EDCF protocol. That small difference implies that the overall Retransmission Attempts made in DCF protocols are a bit lesser than EDCF protocol. Media Access Delay Figure 4.6 Media Access Delay of DCF vs. EDCF In Figure 4.6, for the first minute of simulation the Medium Access Delay for both protocols increases at equal pace, and then after that, DCF suffers somewhat lesser Access Delay than EDCF. The increase in the Medium Access Delay for both protocols is due to increase in the number of nodes competing to gain access of medium. Data Dropped Figure 4.7 amount of Data Dropped of DCF vs. EDCF It is observed from figure 4.7 that the first 30 seconds of simulation, DCF suffers a sudden high Data Drop, but Data Drop in EDCF increases gradually. The reason of varying Data Drop gradually in EDCF is the service differentiation which provides priority based scheme to handle different kind of data. After 2.5 minutes of simulation, curves of Data Dropped of DCF and EDCF remain same for both protocols, EDCF finishes at less Data Dropped than DCF. Conclusions Conclusion The results obtained from simulation shows that Enhanced Distribution Coordination Function provides efficient mechanism for service differentiation and hence provides quality of service to the Wireless LAN. However, this improvement comes at a cost of a decrease in quality of the lower priority traffic up to the point of starvation. The acquisition of the radio channel by the higher priority traffic is much more aggressive than for the lower priority. Higher priority traffic benefited, while lower priority traffic suffered. In terms of overall performance (under the used simulation conditions in this particular study of QoS of Wireless LAN), DCF performs marginally well than EDCF. This happens due to reason that in EDCF mechanism, each AC function acts like a virtual station for medium access, so more collision will be expected for EDCF scenario. But in terms of Quality of Service for real-time applications (like Video conferencing) EDCF outperforms DCF. EDCF has been purposed as the medium access control protocol for IEEEs upcoming standard IEEE 802.11e. Presently, all of the wireless devices use DCF as the default MAC protocol and PCF as the optional functionality.