Nuclear Power Cons Essays - Nuclear Technology, Nuclear Power

Nuclear Power: Cons In our society, nuclear energy has become one of the most criticized forms of energy by the environmentalists. Thus, a look at nuclear energy and the environment and its impact on economic growth. Lewis Munford, an analyst, once wrote, "Too much energy is as fatal as too little, hence the regulation of energy input and output not its unlimited expansion, is in fact one of the main laws of life." This is true when dealing with nuclear power. Because our societies structure and processes both depend upon energy, man is searching for the most efficient and cheapest form of energy that can be used on a long term basis. And because we equate power with growth, the more energy that a country uses, - the greater their expected economic growth. The problem is that energy is considered to have two facets or parts: it is a major source of man-made repercussions as well as being the basis of life support systems. Therefore, we are between two sections in which one is the section of "resource availability and waste", and the other "the continuity of life support systems pertinent to survival." Thus, the environmentalists believe that nuclear energy should not be used for various reasons. First of all, the waste product, i.e. plutonium, is extremely radioactive, which may cause the people who are working or living in or around the area of storage or use, to acquire leukemia and other cancers. They also show how billions of dollars are spent yearly on safety devices for a single reactor, and this still doesn't ensure the impossibility of a "melt down." Two examples were then given of Chernobyl and Three Mile Island, in 1979, when thousands of people were killed and incapacitated. Finally, the environmentalists claim that if society wastes less energy, and develops the means to use the energy more efficiency, then there would be a definite decrease in the requirement for more energy producing plants. On the other hand, some business men and economists say that the present conditions should be kept intact, as the other forms of energy, e.g. oil, natural gas and coal, are only temporary, in dealing with surplus, and give off more pollution with less economic growth. Concurrently, countries wanted a more reliable, smokeless form of energy not controlled by OPEC, and very little uranium was required to produce such a high amount of resultant energy. Lastly, they said that renewable energy is (a) unreliable in that the wind, for example, could not be depended upon to blow, nor the sun to shine, and (b) were intermittent in that a 1,000 mega-watt solar farm may occupy about 5,000 acres of land, compared with less than 150 acres of land for a similar capacity nuclear power generation station. Because the energy technology that society employs directly influences the quantity and quality of life, the energy option that is chosen should have the greatest cost- benefit effectiveness as well as maximizing flexibility and purchases. However, those who believe in continuous energy consumption growth, seem to forget that there is only a limited supply of energy in every energy system, and to "overdo" any resource may provide for an unacceptable impact upon global and regional ecology. Thus, if the business world pushes the environment as far as it can go, Ceribus Paribus, please refer to figure 1. Thus, to use petroleum as a substitute for uranium, which is needed to power the nuclear system, would not be economically or environmentally sensible. I say this because, first of all, there is a major supply of uranium considering it was one of the last energy sources to be found as well as only a small amount of it is required to produce a lot of energy. Secondly, petroleum gives off carbon monoxide which is one of the reasons for ozone depletion; whereas, the uranium does not give off pollution except that it produces plutonium which needs to be buried for more than fifty years to get rid of its radiation. Finally, because so much of the petroleum will be required to power the vast area that nuclear energy can cover, the cost to us as the consumer would be massive! This would mean slower economic growth and/or expansion, especially when compared to nuclear energy. Therefore: Ceribus Paribus - (a) if the cost decreases, the demand increases, and - (b) if the cost increases, the demand decreases. Please refer to figures #2 and #3 respectively. Nuclear plants are now replacing coal burning plants. It will cost the taxpayers far more

Dimensional Analysis in Physics Problems

Dimensional Analysis in Physics Problems Dimensional analysis is a method of using the known units in a problem to help deduce the process of arriving at a solution. These tips will help you apply dimensional analysis to a problem. How Dimensional Analysis Can Help In science, units such as meter, second, and degree Celsius represent quantified physical properties of space, time, and/or matter. The International System of Measurement (SI) units that we use in science consist of seven base units, from which all other units are derived. This means that a good knowledge of the units youre using for a problem can help you figure out how to approach a science problem, especially early on when the equations are simple and the biggest hurdle is memorization. If you look at the units provided within the problem, you can figure out some ways that those units relate to each other and, in turn, this might give you a hint as to what you need to do to solve the problem. This process is known as dimensional analysis. A Basic Example Consider a basic problem that a student might get right after starting physics. Youre given a distance and a time and you have to find the average velocity, but youre completely blanking on the equation you need to do it. Dont panic. If you know your units, you can figure out what the problem should generally look like. Velocity is measured in SI units of m/s. This means that there is a length divided by a time. You have a length and you have a time, so youre good to go. A Not That was an incredibly simple example of a concept that students are introduced to very early in science, well before they actually begin a course in physics. Consider a bit later, however, when youve been introduced to all kinds of complex issues, such as Newtons Laws of Motion and Gravitation. Youre still relatively new to physics, and the equations are still giving you some trouble. You get a problem where you have to calculate the gravitational potential energy of an object. You can remember the equations for force, but the equation for potential energy is slipping away. You know its kind of like force, but slightly different. What are you going to do? Again, a knowledge of units can help. You remember that the equation for gravitational force on an object in Earths gravity and the following terms and units: Fg G * m * mE / r2 Fg is the force of gravity - newtons (N) or kg * m / s2G is the gravitational constant and your teacher kindly provided you with the value of G, which is measured in N * m2 / kg2m mE are mass of the object and Earth, respectively - kgr is the distance between the center of gravity of the objects - m  We want to know U, the potential energy, and we know that energy is measured in Joules (J) or newtons * meter  We also remember that the potential energy equation looks a lot like the force equation, using the same variables in a slightly different way In this case, we actually know a lot more than we need to figure it out. We want the energy, U, which is in J or N * m. The entire force equation is in units of newtons, so to get it in terms of N * m you will need to multiply the entire equation a length measurement. Well, only one length measurement is involved - r - so thats easy. And multiplying the equation by r would just negate an r from the denominator, so the formula we end up with would be: Fg G * m * mE / r We know the units we get will be in terms of N*m, or Joules. And, fortunately, we did study, so it jogs our memory and we bang ourselves on the head and say, Duh, because we should have remembered that. But we didnt. It happens. Fortunately, because we had a good grasp on the units we were able to figure out the relationship between them to get to the formula that we needed. A Tool, Not a Solution As part of your pre-test studying, you should include a bit of time to make sure youre familiar with the units relevant to the section youre working on, especially those that were introduced in that section. It is one other tool to help provide physical intuition about how the concepts youre studying are related. This added level of intuition can be helpful, but it shouldnt be a replacement for studying the rest of the material. Obviously, learning the difference between gravitational force and gravitational energy equations is far better than having to re-derive it haphazardly in the middle of a test. The gravity example was chosen because the force and potential energy equations are so closely related, but that isnt always the case and just multiplying numbers to get the right units, without understanding the underlying equations and relationships, will lead to more errors than solutions.

Brutal Treatment of Women Suffragists at Occoquan

Brutal Treatment of Women Suffragists at Occoquan An email has been circulating that tells of the brutal treatment in 1917 at Occoquan, Virginia, prison, of women who had picketed the White House as part of the campaign to win the vote for women. The point of the email: it took a lot of sacrifice to win the vote for women, and so women today should honor their sacrifice by taking our right to vote seriously, and actually getting to the polls. The author of the article in the email, though the emails usually omit the credit, is Connie Schultz of The Plain Dealer, Cleveland. Is the email true? a reader asks or is it an urban legend? It sure sounds exaggerated but its not. Alice Paul led the more radical wing of those who were working for womens suffrage in 1917. Paul had taken part in more militant suffrage activity in England, including hunger strikes that were met with imprisonment and brutal force-feeding methods. She believed that by bringing such militant tactics to America, the publics sympathy would be turned towards those who protested for woman suffrage, and the vote for women would be won, finally, after seven decades of activism. And so, Alice Paul, Lucy Burns, and others separated in America from the National American Woman Suffrage Association (NAWSA), headed by Carrie Chapman Catt, and formed the Congressional Union for Woman Suffrage (CU) which in 1917 transformed itself into the National Womans Party (NWP). While many of the activists in the NAWSA turned during World War I either to pacifism or to support of Americas war effort, the National Womans Party continued to focus on winning the vote for women. During wartime, they planned and carried out a campaign to picket the White House in Washington, DC. The reaction was, as in Britain, strong and swift: arrest of the picketers and their imprisonment. Some were transferred to an abandoned workhouse located at Occoquan, Virginia. There, the women staged hunger strikes, and, as in Britain, were force-fed brutally and otherwise treated violently. Ive referred to this part of woman suffrage history in other articles, notably when describing the history of the suffragist split over strategy in the last decade of activism before the vote was finally won. Feminist Sonia Pressman Fuentes documents this history in her article on Alice Paul. She includes this re-telling of the story of Occoquan Workhouses Night of Terror, November 15, 1917: Under orders from W. H. Whittaker, superintendent of the Occoquan Workhouse, as many as forty guards with clubs went on a rampage, brutalizing thirty-three jailed suffragists. They beat Lucy Burns, chained her hands to the cell bars above her head, and left her there for the night. They hurled Dora Lewis into a dark cell, smashed her head against an iron bed, and knocked her out cold. Her cellmate Alice Cosu, who believed Mrs. Lewis to be dead, suffered a heart attack. According to affidavits, other women were grabbed, dragged, beaten, choked, slammed, pinched, twisted, and kicked. (source: Barbara Leaming, Katherine Hepburn (New York: Crown Publishers, 1995), 182.) Related Resources: An image of Emmeline Pankhurst, who led the militant British woman suffragists, including hunger strike tactics, which inspired Alice Paul  and the National Womans PartyA firsthand account of this is in Doris Stevens Jailed for Freedom (New York: Liveright Publishing, 1920. (Gutenberg text)The movie Iron Jawed Angels focuses on this period of the woman suffrage movement.Sewall-Belmont House, home of the National Womans Party, is now a museum which includes many archives of these events.The Library of Congress presents some photos of women suffrage prisoners: Suffrage Prisoners

Analyze movie Essay Example | Topics and Well Written Essays - 1000 words

Analyze movie - Essay Example mummy has brought so many questions to light with regards not only to how worthy these claims are but also to the ancient way of life of the past ancestors. The discovery of a man having a copper ax at a time when such thing was not a thing of imagination also begs the question of how accurate the historical dating and recordings are. Many hypotheses were put to explain the discovery of a body in the mount Alps buried in the glacier, the nature of his death and the accuracy of the scientific technology (James). This amazing discovery is what prompted the scripting and finally production of the movie bearing the title â€Å"Iceman Murder Mystery’’. The movie bears all the processes that were involved from the discovery to the final autopsy procedures conducted on the mummified copse of Otzi. The movie however, according to how it was directed depicts or portrays a different theme all together. According to my understanding, the movie tries to portray the fact that human nature remains the same despite the level of advancement achieved in technology and thinking. For this reason, I tend to share a common understanding with Eduard Egarter Vigl on the connection he felt with the Mummy after looking at his face, position of the body and mortality in general. For this reason, was I to be the director of the movie, I would have named or titled it â€Å"Otzi the Stone Age modern man: A Reflection Of human Socio-cultural connectedness to the Past†. The movie in my observation was cast to reflect in the human nature that never changes despite the number of years that pass by. This is supported by almost all the theories that were put forward to explain the cause of death of the Mummy. The theory that now support this argument even further is the one that is seen to be favoured most about the death resulting from not, an animal, not another skirmishes, not any falling glacier but a person from the inside of where Otzi was coming from. This though not well explained in the

Abortion Essay Example | Topics and Well Written Essays - 250 words - 10

Abortion - Essay Example For most women, giving birth changes their lives. Women who are working or schooling can find abortion appropriate. Relationships problem and a desire to avoid single motherhood can also make abortion necessary (Finer et. al. Web). Sometimes conditions exist, both physical and mental that endanger the life of a pregnant woman, an abortion can be performed to save the life (WebMD Web). Additionally, abortion can help a raped woman to cope with the trauma that ensues. In a case of teenage pregnancy abortion affords the girl a chance to continue living her life normally. On the other hand, there are various reasons to support an argument against abortion. Life is precious even for the unborn children, but abortion steals the joy to live. If an abortion the procedure is not safely conducted, the woman risks developing health complications that could lead to death. The guilt associated with terminating pregnancy in some cases, causes women to suffer post-traumatic stress disorder (Operation Rescue Web). Practise of abortion help sidestep the real issues that women experience. Raped women should be concerned with rape rather than opting for an abortion. To conclude, abortion is an issue that requires a cautious

Confessions of an Economic Hit Man | Book Summary

Confessions of an Economic Hit Man | Book Summary Confessions of an Economic Hit Man is an autobiography by John Perkins. It tells the story of how the protagonist, Perkins, experienced a series of events that are astonishingly influential to the world that we live in today. It tells the story of how greed for money and power creates a web of deceit, traitors and shockingly murderers. It portrays how one country can exploit others, rob their natural resources, cause environmental disasters, poison their rivers and guide their politics. Perkins exposes the truth behind his own countrys administrations and its leading role models in the corporate world The United States of America. Perkins begins this book by introducing two concepts; Economic Hit Man (EHM) and corporatocracy. EHMs are a group of people who encourage world leaders to become part of a vast network that promotes U.S commercial interests (p ix). This results in the world leaders becoming trapped in a web of debt and providing the U.S with support politically, militarily and economically. In turn, the world leaders bring airports, power plants and industrial parks to their people and therefore guarantee their thrown. John Perkins provides a precise definition of EHMs that they are highly paid professionals who cheat countries around the globe out of trillions of dollars using techniques such as fraudulent financial reports, rigged elections, payoffs, extortion, sex and murder (p ix). The protagonist was an EHM for the international consultancy firm MAIN and its strategy is to target and persuade poorer country leaders to accept enormous development loans for projects which were to be contracted with U.S companies. They cheat leaders with false economic projections, Your forecasts determine the magnitude of the systems they design and the size of the loans , an EHM is the key (p 17). This form of diabolic manipulation, in their view a strategic investment, proved to be successful in countries such Ecuador, Panama and Saudi Arabia but if the leaders do not comply with the offer for loans and economic growth then the country and their leaders suffered, even murdered. EHM failure was not acceptable. The term corpratocracy as Perkins explains is a collective term describing corporations, banks and governments that work for the progression of the global empire using financial and political muscle to ensure that our schools, businesses and media support the concept of the system that is motivated by the illusion that all economic growth serves for the prosperity of mankind and the larger the growth, the further extended the benefits and that the impoverished are convenient for exploitation. Perkins also gives us an insight of the impact of corporatocracy on us as we are being exploited by the economic engine that creates an insatiable appetite for the worlds resources and results in a system that fosters slavery. This quote emphasises what we encounter everyday in our lives; in banks, governments, Nike and Wal-Mart and nearly every other corporation in the world and that we are convinced by this economic engine and induced to consume, consume, consume (p xii -xiii). A key question is why did John Perkins become an EHM? He implies that his choice of this career path was due to two events in his life; his loyal friendship with Farhad, a son of an Iranian general and his encounter with Anne, his ex-wife (p 5). His parents also played a role in his point of view since he grew up as a poor puritan among so many wealthy. According to the protagonist, living a life of frustration craving sex and money generated a pivotal role in establishing his aspiration to live the good life, which was the lure that MAIN adopted to mould him into an EHM (p 7). But the more vital question here is how was such a disbeliever in the corporatocracy become ensnared in its web of deceit? The answer is the manipulative strategy of exploitation. Perkins wife introduced him to an executive at the NSA (National Security Agency). Perkins then undergone a series of NSA assessments were focused on his frustrations, his upbringing and his relationship with his friend Farhad. This portrayed how seducible the protagonist was and he was later further lured indirectly to be trained as an EHM (p 9). When he began to realize the true nature of EHMs, he became juxtaposed between becoming one and living the good life or walking away. He often questioned if what he was about to engage in was right and suspected he was not but eventually greed and the appealing opportunities MAIN offered won and he justified his decision by presupposing that he will expose the corporatocracy after he advanced deeper (p 17). EHMs have been involved Panama, Saudi Arabia, Iraq and Ecuador. In each case the author describes various strategic tactics they employ and their various outcomes to the countries leaders, politics and people. Panama was ruled by its hero Omar Torrijos at the time Perkins was sent to make his economic forecasts (or in reality an economic hit). Torrijos believed in his countries right to rule its own Panama Canal with no U.S intervention (p38). In 1972, Perkins established a relationship with Torrijos where it appeared that the he knew MAINs true agenda towards Panama as he implies, I understand that your company wants more work and usually gets it by inflating the size of projects.. This time is different Give me whats best for my people .Ill give you all the work you want. It was obvious that this man was solely concerned for the benefit of his country and to benefit the poor as rather than himself and which in my point of view proves that not all leaders are corrupt. Perkins also portrays that Torrijoss selfless attitude would be seen as a threat but Torrijos expressed his knowledge openly that at anytime the U.S could assassinate him and that he will not be destroyed easily, We have the Canal The CIA will have to kill me! (p 72-75). His expectations came to life on July 31st 1981. His death, which my mother described as a mysterious plane crash, was a result of his true devotion to Panama rather than the U.S dollar. He renegotiated the Canal Treaty with the U.S President Jimmy Carter to surrender the Canal to the Panamanians and later refused to renegotiate it with President Reagan. The U.S wanted sole control over the Canal. When anything came in their way, the words CIA assassination are heard (p158-159). This is their strategy, either comply with their strategic exploitation game and sell your beliefs for dollars and power or they send in their jackals or the CIA to intervene. After the tragic assassination of Panamas hero, his replacement, Manuel Noriega, followed in his footsteps particularly with the project of building a new canal financed by the Japanese. This posed a threat to U.S firms; they could lose billions of dollars. During the George H. W. Bush administration a new strategy emerged to deal with Noriegas intentions. It was through loss of reputation and mass murder. In 1986, they developed a corrupt image of drug dealing for Noriega. In 1989, the U.S invades Panama with airstrike assaults on the unharmful Panamanian civilians violating international law (p 173-175). Perkins wrote about Ecuador and how the U.S oil company ChevronTexaco Corp contaminated rivers and open holes with four million gallons of toxic waste water which contained oil, carcinogens and heavy metals which poisons the Ecuadorian people and their animals (p xviii). Their democratically elected President Jaime Roldos wanted oil companies out of his country, unless they implemented plans that would help Ecuadors people, they would be forced to leave his country. His people were frustrated and so was he. This posed a threat to their strategy of corporatocracy, therefore a CIA assassination strategy was implemented and he died in a plane crash two months before Torrijos in 1981 (p 154-156). In 1973, an important event occurred that changed the strategy of corporatocracy, the Oil Embargo. This was due to the U.Ss support to the state of Israel both politically and with foreign aid. This caused five Arab countries including Saudi Arabia to stop oil shipments to the U.S (p 82-83). King Faisal of Saudi Arabia played a great role in this embargo since he believed in the freedom of Palestine and swore to pray in Jerusalems Aqsa Mosque. But like any leader that opposed U.S interests he was murdered in 1975 by his own nephew who coincidentally was just being educated in the U.S. As for their strategy for oil rich and strategically located countries such as Saudi Arabia, they sent EHMs, including Perkins team, to the House of Saud, with their strategic weapon, economic projections. In order to preserve their oil supply, Washington commenced a new strategy to lure the wealthy House of Saud using negotiations offering technical support, military hardware and training, and an opportunity to bring their nation into the twentieth century. This arrangement would guarantee the House of Sauds power and the U.S would receive large portions of petrodollars and forever making Saudis dependent on the U.S companies, such as MAIN. Perkins role was to forecast rough projections of the future of the kingdom if large sums of money were invested in its infrastructure by the aid of U.S construction and engineering companies. He described it as win-win situation (p 83-85). The author was assigned to persuade a member of the Saudi government, Prince W., of a possible new Westernised future of the kingdom in 1975. The protagonist soon realized his weakness for beautiful blondes. And he exploited that weakness and supplied him with his need of women which portrays the measures EHMs result in order to fulfil their assignment. Indeed his technique proved to be a success and Prince W. eventually relented (p 92-95). The diabolic outcome of this strategy is not the result of having a guaranteed unlimited oil support, but is the message the U.S sent; If other countries such as Iran, Iraq threatened embargoes, Saudi Arabia would step in discourage other countries from even considering an embargo (p 90). The U.S can not only further corporatocracy but it can even escape with supporting terrorists for their own gain and later pursuing them as outlaws. The U.S desired the House of Saud to bankroll Osama bin Ladens Afghan war against the Soviet Union in the 1980s and they both generously devoted $3.5 billion to the mujahideen resistance movement (p 99). Washington was supporting who it now name murderers and terrorists to further its political agenda, in fact it was an excellent strategy to exploit such movements and later destroy them. Since the success of the Saudi Arabia strategy in the 70s, the greed of the corporatocracy grew and EHMs were sent to Saddam Hussein of Iraq to exploit his oil reserves in exchange for infrastructural prosperity. Unlike the House of Saud, he did not comply. To Washington, Iraq represented oil, water and its borders with Jordan, Kuwait, Saudi Arabia, Syria, Turkey, and Iran. It is at strike distance with Israel and the former Soviet Union. That would have control over its neighbours; some which are oil rich (p 182-184). Refusing to comply, Iraq was attacked twice breaking international law. Once by George H. W. Bush in the 1990s with air strikes and aerial assaults on civilians. And second, by George W. Bush in 2003 where he deceived the world by claiming Hussein owned weapons of mass destruction. But people implied at that time that he planned to sell his oil for Euros which triggered the war. John Perkins book furthered a vast amount of knowledge to my perception of world leaders. I was always sceptical about many leaders but never did I know about EHMs. I was aware about corruption in governments, the U.S compliance with terrorism and its double standards that caused the murder of generations, the emotional scaring of orphans and the theft of dignity, resources and morals of many countries. Personal examples of this is the differenced between the Egyptian government at the time of Anwar Sadat who fought to help free Palestine and stop the Israeli genocide and now where Israelis are using chemical weapons to bomb schools and orphan children and the Egyptians are denying charities to supply those children with food. In my point of view this is also due to the U.Ss strategic exploitation as Egypt relies on billions of U.S foreign aid. I believe that EHMs were in Egypt. Another example is Saudi Arabia and how its leaders stood watching the U.S butcher Iraqi civilians in the war in 2003 and allowed U.S helicopters fly to Iraq via Saudi Arabia. After reading this book, I also thought of mysterious assassinations of important politicians such as Rafic Al Hariri who was a supporter of Hezbollah who protected Lebanon from Israeli occupation and Benazir Bhutto of Pakistan. Those were people of similar standards as Torrijos and Roldos and perhaps I am right to now believe that those were CIA assassinations. The extent of the use of exploitation strategies by the corporatocracy was appalling and in my point of view the author was convincing and he was right to quit and expose this form of manipulation and terrorism employed by the U.S. As for a solution for corporatocracy, I believe it is in the reason of its existence, the reason why Perkins joined it, the same reason it was created; greed and power hunger. If we can perhaps teach American schools the importance of the life, liberty and pursuit of happiness of every country, not just theirs and about international laws, then they might realise the real terrorists. I agree with J ohn Perkins on his strategy of spreading awareness, using his book and the media, and his idea giving this book and talking about it to friends and family. I would also suggest translating this book in different languages, especially Arabic and giving it to Iraqis and Saudis so they can see for themselves the working of the corporatocracy in their everyday life.

Analysis of Secure Real Time Transport Protocol on Voip over

Mohd Nazri Ismail / (IJCSE) International Journal on Computer Science and Engineering Vol. 02, No. 03, 2010, 898-902 Analysis of Secure Real Time Transport Protocol on VoIP over Wireless LAN in Campus Environment Mohd Nazri Ismail Department of MIIT, University of Kuala Lumpur (UniKL), MALAYSIA [email  protected] unikl. edu. my Abstract- In this research, we propose to implement Secure Real Time Transport Protocol (SRTP) on VoIP services in campus environment. Today, the deployment of VoIP in campus environment over wireless local area network (WLAN) is not considered on security during communication between two parties.Therefore, this study is to analyzed SRTP performance on different VoIP codec selection over wired. We have implemented a real VoIP network in University of Kuala Lumpur (UniKL), Malaysia. We use softphone as our medium communication between two parties in campus environment. The results show that implementation of SRTP is able to improve the VoIP quality between on e-to-one conversation and multi conference call (many-to-many). In our experiment, it shows that iLBC, SPEEX and GSM codec are able to improve significantly the multi conference (many-to-many) VoIP quality during conversation.In additional, implementation of SRTP on G. 711 and G. 726 codec will decrease the multi conference (many-to-many) VoIP quality. Keywords- Codecs, Softphone, SRTP, WLAN I. INTRODUCTION AND RELATED WORKS University of Kuala Lumpur (UniKL) has implemented a real VoIP over wireless LAN in campus environment. This implementation is not covered any security features. Therefore, the objective of this study is to enable the security function using Secure Real Time Transport Protocol (SRTP).We will study the performance of SRTP on different codec such as G. 711, G. 726, GSM, iLBC and SPEEX. iLBC is a speech codec developed for robust voice communication over IP, it uses 13. 33 Kbps. It provides low delay and high packet loss robustness for low-bit rate codec’s. SPEEX codec is open source patent-free audio compression format designed for speech. Codec is an algorithm used to encode and decode the voice conversation. Secure Real Time Transport Protocol (SRTP) defines a profile of Real Time Transport Protocol (RTP), intended to provide ncryption, message authentication and integrity and replay protection to the RTP data in both unicast and multicast applications. Previous work is to evaluate the trade-off existing between quality of service and security when SRTP [6] is employed to protect RTP (Real Time Protocol) sessions on VoIP calls [5]. There is no such study has been conducted on comparison of VoIP one-to-one call and multi conference call (many-to-many) performance using SRTP functionality. With its promise of inclusion, innovation, and growth, VoIP also brings challenges. VoIP is not easy to secure.It suffers all of the problems associated with any Internet application, and VoIP security is complicated by its interconnection to the PS TN. A host of trust, implementation, and operational complexities make securing VoIP particularly complex. In fact, the same aspects that make the VoIP software model so powerful—its flexible, open, distributed design—are what make it potentially problematic [7][8]. Various security requirements have to be met to secure VoIP transmission: Authentication, Privacy and Confidentiality, Integrity, Non repudiation, Non replay and Resource availability [9].The threats faced by a VoIP are similar to other applications including: unwanted communication (spam), privacy violations (unlawful intercept), impersonation (masquerading), theft-of service, and denial-of-service [10]. II. METHODOLOGY We have setup a real wireless network environment to analyze and measure implementation of VoIP service using security function (SRTP) at University of Kuala Lumpur (UniKL) in Malaysia. This study posits several research questions: i) what is the STRP performance level of the VoIP over WLAN based on one-to-one call and multi conference call? nd ii) which codecs are able to provide better improvement of VoIP conversation? Figure 2. 1 and Figure 2. 2 show the flow of VoIP conversation call between one-to-one and multi conference. We measure our voice quality using human perception. Mean Opinion Score (MOS) technique is the best approach to measure and ISSN : 0975-3397 898 Mohd Nazri Ismail / (IJCSE) International Journal on Computer Science and Engineering Vol. 02, No. 03, 2010, 898-902 validate voice quality between one-to-one call and multi conference call. Figure 2. 3 shows the measurement of VoIP performance over WLAN using SRTP implementation.We also test on different codecs selection such G. 711, G. 726, GSM, iLBC and SPEEX. III. ANALYSIS AND RESULTS Figure 2. 1: VoIP over One-to-One Conversation This section measures and compares VoIP performance over WLAN using SRTP function. In voice and video communication, quality usually dictates whether the experience is a good or bad one. Besides the qualitative description we hear, like ‘quite good' or ‘very bad', there is a numerical method of expressing voice and video quality. It is called Mean Opinion Score (MOS). MOS can be tested using: i) human perception; ii) simulation model; and iii) automated system [1] [2].MOS gives a numerical indication of the perceived quality of the media received after being transmitted and eventually compressed using codecs. MOS is expressed in one number, from 1 to 5, 1 being the worst and 5 the best. MOS is quite subjective; as it is based figures that result from what is perceived by people during tests (refer to Table 3. 1). We will select five different users to evaluate and rate the VoIP performance using SRTP and without SRTP functionality. When users cannot get a dial tone or there are excessive delays in ringing the other party’s phone, VoIP performance is unacceptable.Call quality is a function of packet loss rate, delay, and jitter is typically represented as a MOS [3], [4]. Table 3. 1: Mean Opinion Score (MOS) Ratings Mean Opinion Score (MOS) Ratings Excellent 5 (Perfect. Like face-to-face conversation Figure 2. 2: VoIP over Many-to-Many (Multi Conference) Conversation Good Fair Poor Bad or radio reception) 4 (Fair. Imperfections can be perceived, but sound still clear. This is (supposedly) the range for cell phones) 3 (Annoying) 2 (Very annoying. Nearly impossible to communicate) 1 (Impossible to communicate) Figure 3. shows the configuration of codec protocol such as G. 711, G. 726, GSM, iLBC and SPEEX. This 3CX softphone is able to active ‘Echo Cancellation’ and ‘SRTP’. The VoIP experiments will receive two types of modes: i) one-to-one call conversation; ii) multi conference call (many-to-many). Figure 3. 2 shows the result of VoIP one-to-one conversation. Figure 3. 3 shows the result of VoIP multi conference (many-to-many) call. Figure 2. 3: Measurement and Evaluation of VoIP over WLAN using SRTP Approach ISSN : 0975-3397 899 Mohd Nazri Ismail / (IJCSE) International Journal on Computer Science and Engineering Vol. 2, No. 03, 2010, 898-902 improvement on VoIP quality performance and at the same time able to provide element of security (refer to Table 3. 3 and Figure 3. 5). The significant improvement is GSM and SPEEX codecs after implemented SRTP. Table 3. 2: Multi Conference without SRTP User Codec Figure 3. 1: 3CX Softphone Codec and SRTP Configuration G. 711 G. 726 GSM iLBC SPEEX User 1 3 4 1 2 5 User 2 3 3 1 2 4 User 3 2 3 1 3 4 User 4 3 4 1 2 4 User 5 2 4 1 2 5 Figure 3. 2: One-to-One Call Conversation Result Figure 3. 4: Users Rate VoIP for Multi Conference Call Without SRTP Table 3. : Multi Conference with SRTP User Codec G. 711 G. 726 GSM iLBC SPEEX Figure 3. 3: Multi Conference Call (many-tomany) Conversation Result Most of the users agreed and rates this VoIP without SRTP will provide a good quality for G. 711 and G. 726 codecs. Other users agreed a nd rates 4 to 5 ratings for SPEEX codec without using SRTP during multi conference conversation (refer to Table 3. 2 and Figure 3. 4). After implemented SRTP on VoIP during multi conference session occurs, it shows some User 1 2 3 4 5 5 User 2 1 3 4 5 5 User 3 1 2 3 4 5 User 4 2 2 3 4 5 User 5 1 2 3 4 5 ISSN : 0975-3397 900Mohd Nazri Ismail / (IJCSE) International Journal on Computer Science and Engineering Vol. 02, No. 03, 2010, 898-902 Table 3. 5: One-to-One Call with SRTP User Codec G. 711 G. 726 GSM iLBC SPEEX User 1 2 3 2 4 5 User 2 1 3 2 4 4 User 3 1 2 2 4 5 User 4 2 2 2 4 4 User 5 2 3 2 4 5 Figure 3. 5: Users Rate VoIP for Multi Conference Call With SRTP Most of the users agreed and rates this VoIP oneto-one call without SRTP will also provide low quality for G. 711, G. 726 and GSM codecs. Other users agreed and rates 3 and 5 ratings for iLBC and SPEEX codecs without using SRTP during one-to-one call (refer to Table 3. and Figure 3. 6). After implemented SRTP on VoIP during o ne-to-one session occurs, it shows significant improvement on VoIP quality performance for G. 711, G. 726, GSM, iLBC and SPEEX over WLAN (refer to Table 3. 5 and Figure 3. 7). Table 3. 4: One-to-One Call Without SRTP User Codec G. 711 G. 726 GSM iLBC SPEEX User 1 2 1 2 3 5 User 2 2 2 2 3 4 User 3 2 1 2 4 4 User 4 1 1 1 3 4 User 5 1 2 2 4 4 Figure 3. 7: Users Rate VoIP for One-to-One Call with SRTP Figure 3. 8 and Figure 3. 9 show the average MOS score for VoIP conversation over one-to-one call and multi conference call (many-to-many), respectively.VoIP Conversation over Multi Conference Call: Before implemented SRTP, the average MOS score for G. 711 is 2. 5, 3. 5 for G. 726, 1 for GSM, 2. 1 for iLBC and 4. 5 for SPEEX. After implemented SRTP, the average MOS score for G. 711 and G. 726 are decreased the ratings approximately 1 to 2. 5. GSM, iLBC and SPEEX codecs show the average MOS score are 3. 5, 4. 5 and 5. GSM, iLBC and SPEEX codec show the increasing of VoIP performance after i mplemented SRTP (refer to Figure 3. 8). VoIP Conversation over One-to-One Call: Before implemented SRTP, the average MOS score for G. 711 is 1. , 1. 4 for G. 726, 1. 8 for GSM, 3. 5 for iLBC and 4. 2 for SPEEX. After implemented SRTP, the average MOS score shows the significant improvement for G. 711, G. 726, GSM, iLBC and SPEEX codecs. Therefore, implementation of SRTP can improve the VoIP quality performance for one-to-one call over WLAN (refer to Figure 3. 9). Figure 3. 6: Users Rate VoIP for One-to-One Call without SRTP ISSN : 0975-3397 901 Mohd Nazri Ismail / (IJCSE) International Journal on Computer Science and Engineering Vol. 02, No. 03, 2010, 898-902 dependency conditions that could influence voice quality.Future work, we will extend our experiment on VoIP over VPN implementation in Campus environment. References [1]. Moura N. T. ; Vianna B. A. ; Albuquergue C. V. N; Rebello V. E. F & Boeres C. â€Å"MOS-Based Rate Adaption for VoIP Sources†. IEEE International Confe rence on Communication, pp. 628-633, 2007. [2]. Masuda M. & Ori K. â€Å"Delay Variation Metrics for Speech Quality Estimation of VoIP†. Institute of Electronics, Information and Communication Engineers (IEIC) Technical Report, Vol. 101(11), pp. 101-106, 2001. [3]. R. G. Cole & J. H. Rosenbluth. â€Å"Voice over IP Performance Monitoring†. SIGCOMM Computer Communication Rev.Vol. 31(2), pp. 9-24, 2001. [4]. L. Ding & R. Goubran. â€Å"Speech Quality Prediction in VoIP Using the Extended e-Model. Global Telecommunication Conference, GLOBECOM ’03. IEEE, Vol. 7, pp. 3974-3978, 2003. [5]. Alexandre P. ; Edjair M. ; & Edjard M. â€Å"Analysis of the Secure RTP Protocol on Voice over Wireless Networks using Extended MedQoS†. Proceedings of the 2009 ACM symposium on Applied Computing, pp. 86 – 87, 2009. [6]. M. Baugher, D. McGrew, M. Naslund, E. Carrara, & K. Norrman. â€Å"The Secure Real- Time Transport Protocol (SRTP)†. RFC 3711 (Proposed Standa rd), March 2004. [7] Douglas C. Sicker & Tom L. VoIP Security: Not an Afterthought†, FEATURE: Q focus: Voice Over IP, Vol. 2(6), pp. 56-64, 2004. [8] Vesselin I. , Theodor T. , & Amdt T. â€Å"Experiences in VoIP telephone network security policy at the University of Applied Sciences (FHTW) Berlin†, Proceedings of the 2007 international conference on Computer systems and technologies, Bulgaria, Vol. 285(3), 2007. [9] Wafaa B. D. , Samir T. , & Carole B. â€Å"Critical vpn security analysis and new approach for securing voip communications over vpn networks†, Proceedings of the 3rd ACM workshop on Wireless multimedia networking and performance modelling,Chania, Crete Island, Greece, pp. 2-96, 2007. [10] Nekita A. C. , & Chhabria S. A. â€Å"Multiple design patterns for voice over IP security†, Proceedings of the International Conference on Advances in Computing, Communication and Control, Mumbai, India, pp. 530 – 534, 2009. Figure 3. 8: VoIP Conversa tion over Multi Conference Call over WLAN Figure 3. 9: VoIP Conversation over One-to-One Call over WLAN IV. CONCLUSION AND FUTURE WORK Based on the results, implementation of SRTP using GSM, iLBC and SPEEX codecs are able to generate high quality of VoIP conversation WLAN for one-to-one conversation and multi conference call (many-to-many).After implemented SRTP for multi conference call (many-to-many), the MOS result indicates that G. 711 and G. 726 codec will decrease the performance of VoIP conversation over WLAN. Overall of our finding, it confirms that enable SRTP will improve and increase the quality of one-to-one VoIP conversation and VoIP over multi conference call (only for iLBC, GSM and SPEEX codecs). Since the manual/human MOS tests are quite subjective and less than productive in many ways, there are nowadays a number of software tools that carry out automated MOS testing in a VoIP deployment.Although they lack the human touch, the good thing with these tests is that the y take into account all the network ISSN : 0975-3397 902 Copyright of International Journal on Computer Science & Engineering is the property of Engg Journals Publications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.