Work-Related Project Analysis Essay Example for Free

Work-Related Project Analysis Essay Note: Usethe same project addressed in the Work-Related Project Analysis, Part II. Consider this as a follow-up, incorporating the transition from design to implementation for selected business system at the department or division level. Write a 1,400- to 2,100-wordpaper describing the development and implementation stages for the situation specified in previous weeks.Include the following:  · A discussion of major activities, including coding, testing, installation, documentation, training, and support.Include specific descriptions of how each activity would be planned for the individual project. Provide reasonable assumptions where needed.  · A discussion of benefits of using defined and repeatable processes for accomplishing these activities for implementation Include 3 to 4 references relevant to the assignment, in addition to the assigned readings. These should relate to the best practices in the area being discussed this week. References should not only provide definitions to  the words used, but also validate your discussion in the paper. Format your paperconsistent with APA guidelines. AS you already know, there are as many ways to succeed in college as their are to fail. The important thing is to know yourself and create a college plan that works for your lifestyle, your learning style and work ethic. Us the tips from the article above to create your own winning c To download this tutorial follow the link https://bitly.com/12BNn3Z AS you already know, there are as many ways to succeed in college as their are to fail. The important thing is to know yourself and create a college plan that works for your lifestyle, your learning style and work ethic. Us the tips from the article above to create your own winning college strategy. Business General Business Individual Work-Related Project Analysis, Part III Resources: Work-Related Project Analysis, Parts I and II Note: Usethe same project addressed in the Work-Related Project Analysis, Part II. Consider this as a follow-up, incorporating the transition from design to implementation for selected business system at the department or division level. Write a 1,400- to 2,100-wordpaper describing the development and implementation stages for the situation specified in previous weeks.Include the following:  · A discussion of major activities, including coding, testing, installation, documentation, training, and support.Include specific descriptions of how each activity would be planned for the individual  project. Provide reasonable assumptions where needed.  · A discussion of benefits of using defined and repeatable processes for accomplishing these activities for implementation Include 3 to 4 references relevant to the assignment, in addition to the assigned readings. These should relate to the best practices in the area being discussed this week. References should not only provide definitions to the words used, but also validate your discussion in the paper.

Oedipal Complex in the Tragedy of Hamlet Essay Example for Free

Oedipal Complex in the Tragedy of Hamlet Essay How might the Oedipal complex factor into the tragedy of Hamlet? Oedipal complex Freud’s theory of stages of development for boys To describe a boy’s feelings of desire for his mother and jealously and anger towards his father Also thought boys felt they were in a completion with their father for possession of his mother His father is looked at as a rival They boy is observing his father in hopes of being like him or even better Those that carry on these feelings into adulthood are considered to have an Oedipus Complex During the Gibson movie Hamlet hates his uncle/step father; Claudius which Freud says is alright. Claudius is now the new king of Denmark We guess Hamlet would have taken the throne eventually if Queen Gertrude had not remarried. It seems like Claudius and Hamlet have built a rivalry and are in a competition for Gertrude. Because Hamlet feels like Claudius has taken his place next to Gertrude. One of the most controversial scenes in the Gibson movie is when Hamlet goes into Gertrude’s bedroom and confronts her about Claudius. He tells her not to have sex with Claudius (jealousy) He’s obsessed with the thought of his mother in bed During this confrontation there is a lot of sexual tension between the two The movie shows them passionately kissing What other comparisons can we draw between Hamlet and Oedipus? Similarities Differences Oedipus earned the trust of his people Oedipus acts on his actions How could one make the argument that the mother figure is the root of all problems in the play? What is the role of King Hamlet’s ghost in the play? How do you know that it is not a figment of Hamlet’s imagination? Why can’t Gertrude see it? Does Hamlet love Ophelia? How does one obtain power in Hamlet? Explain the importance or lack of importance of thinking and action. How do the Id, Ego, and Superego emerge in the play? At what point in the movie do you believe Hamlet crossed â€Å"a line of madness†? Does he come back? When? How is Hamlet being portrayed in the Gibson movie, the other movie, and the play? What other dramatic differences can you identity among the play’s text, the Gibson version, and the third version that you viewed? The biggest difference between the play and the Gibson version is that Fortinbus isn’t mentioned.

Asthma Essay With Conclusions

Asthma Essay With Conclusions Asthma is one of the major chronic respiratory conditions which alter the respiratory function of the body. The World Health Organisation or WHO (2012) defines asthma as a chronic inflammatory disease of the airways characterised by frequent episodes of breathlessness and wheezing. This difficulty in breathing is caused by the swelling and constricting of the airways. Exposure to allergens, pollutants, cold air, infection and exercise can increase the risk of asthmatics having an attack (Funnel, Koutoukidis and Lawrence 2009). This essay will discuss on the pathophysiology, diagnosis, medical management and clinical manifestations of asthma. It will also cover the client education needed to provide for those with asthma, asthmas risk factors and its prognosis. According to the National Asthma Council of Australia or NACA (2006) more than 2.2 million Australians are suffering from asthma. This essay will therefore also describe how asthma impacts on its victims and their life style. Kaufman (2011) describes the pathophysiology of asthma as a pathologic condition which affects the lower respiratory tract by narrowing the airways as a result of epithelial damage, excessive mucus production, oedema, bronchoconstriction and muscle damage. In asthma the cells in the epithelium layer can be destroyed and peel away, making the respiratory tract more susceptible to allergens and infections, thereby contributing to airway hyper-responsiveness (Kaufman 2011). Asthma also triggers the development of mucus cells and mucus glands. This increases mucus production, thus forming mucous plugs which can obstruct the airways (Monahan et al. 2007). Airway oedema is another change that occurs in the respiratory tract due to asthma. It involves the dilation and leaking of capillaries in the airway walls which limits airflow (Kaufman 2011). Monahan et al. (2007) add that increased capillary permeability and leakage can obstruct the airways due to swelling. They also explain that the i nflammatory agents such as histamine, tryptase, leukotriences and prostaglandins act on smooth muscles of airway walls and cause bronchoconstriction which restricts the airflow to alveoli. Brown and Edwards (2012) write that wheezing, breathlessness, chest tightness and cough are the most common clinical manifestations of asthma. They can occur especially at night and in the early morning and can vary from person to person. It is not necessary to have all the symptoms at once as different symptoms can occur at different times. According to NACA (2006) frequent cough, feeling weak, wheezing after exercise, shortness of breath and sleeping difficulties can be early signs of asthma while severe wheezing, continuous cough, rapid breathing, anxiety, chest pain, blue lips and fingernails are the symptoms of severe asthma attacks. Diagnosing asthma can be done by obtaining a detailed history, performing physical examinations, pulmonary function testing, and laboratory assessments (Ignatavicius and Workman 2010) According to Ignatavicius and Workman (2010) it is important to ask patients about any experiences of having shortness of breath, cough, chest tightness, wheeze and increased mucus production as well as about their smoking habits and any family history of asthma. The same source write that physical examinations can be performed by listening to the patients chest for any wheezing sounds and observing respiratory effort by assessing the respiratory rate and examining whether the patient is using any accessory muscles to breathe. They add that the shape of the chest also needs to be examined, as a barrel-shaped chest can be a sign of prolonged asthma. In addition, the oral mucosa and nail beds need to be examined for any bluish tinge (Ignatavicius and Workman 2010). Ignatavicius and Workman (2010) write that pulmonary function tests (PFTs), usually using spirometry, are the most accurate tests that can be performed to diagnose asthma. According to the National Heart Lung and Blood Institute (2012) this test measures how much air the patient can breathe in and out as well as how fast the patient can exhale it. Christensen and Kockrow (2011) add that PFTs determine the reversibility of bronchoconstriction which helps to diagnose asthma. In addition, arterial blood gases testing (ABGs) and sputum for culture testing are both laboratory tests that can be used to diagnose asthma further. The results of ABGs are used to assess the oxygen and carbon dioxide levels in the blood during an asthma attack, while the presence of eosinophils is assessed in sputum testing (Monahan et al. 2007). Finally, chest X-rays can be used to track any changes in chest structure such as hyperinflation, mucous build up and lung collapse (Brown Edwards 2012). There is no known cure for asthma. Its medical management therefore involves managing its symptoms, either by maintaining stability with long term medications or quickly relieving symptoms of an attack (Brown Edwards 2012). Christensen and Kockrow (2011) write that maintenance drugs aim to prevent and minimize asthmas symptoms but need to be taken regularly. According to Tiziani (2010) these drugs are called symptom controllers. They include salmeterol and formoterol, (catergorised as long acting beta-2-agonists), and inhaled corticosteroids such as fluticasone and budesonide. Leukotriene modifiers are also used for the treatment of chronic asthma (Christensen and Kockrow 2011). Symptom relievers, on the other hand, are used for the immediate treatment and relief of symptoms in an acute asthma attack. They include short-acting beta-2 agonists (Salbutamol, terbutaline), oral or IV corticosteroids and epinephrine (Christensen and Kockrow 2011). According to Christensen and Kockrow (2011) short-acting beta-2-agonists are the most effective drugs for relieving asthma symptoms. They add that epinephrine can be administered subcutaneously and intramuscularly when asthmas symptoms cannot be relieved by beta-2-agonists. Oxygen therapy is also an essential immediately treatment for an acute asthma attack, write Christensen and Kockrow (2011). Because of the absence of a cure and a need for its management, client education on managing asthma is an important role undertaken by health care professionals. Clients should be educated about the signs and symptoms of asthma and its triggers, in order to lessen and prevent asthma attacks (Monahan et al. 2007). According to Ignatavicius and Workman (2010) clients should also be educated to assess their respiratory status, take their medication at the correct dosage and determine when to see their health professionals. Clients therefore need to be educated about the method of using peak flow meters, metered dose inhalers and inhalers with spacers. Monahan et al. (2007) add that a nurse should teach relaxation exercises to patients and the importance of not smoking. Ignatavicius and Workman (2010) describe that patients also need to be educated to have adequate rest and sleep, proper nutrition and fluid intake. According to NACA (2012) the risk factors of asthma are allergens, pollutants, drugs, infections, smoking, occupational factors, exercise and temperature change. Allergens known to trigger asthma include house dust mites, animal fur, moulds, pollens, tobacco smoke, bushfire smoke, paint fumes, household cleaning products and air pollutants (National Asthma Council Australia 2012). Asprin, other NSAIDs and complementary medicines can trigger asthma as well, according to Brown and Edwards (2012). Cold and flu can act as infection triggers while dust, chemicals and stress are considered occupational factors that can trigger an attack. The prognosis of asthma, however, is generally good because it can be managed by proper and timely treatment. According to Harvey (2011) most deaths from asthma are preventable, while mild to moderate asthma can be improved with proper management, making some adults symptom-free. Severe episodes also can be managed, depending on the treatment and the degree of obstruction in the airways. On the other hand, asthma causes irreversible problems in lung function for about 10% of patients even though it is well treated while poor treatment and control can lead to prolonged asthma and permanent disabilities (Harvey 2011). Other relevant information about asthma includes 235 million people suffering from it globally, with most asthma-related deaths occurring in lower and middle income countries (WHO 2012). In addition, the prevalence of asthma increases with the age and it is also more common in females than males after the teenage years (AIHW 2012). According to Andrews (2010) fruits and vegetables in the diet improve lung function while foods rich in Omega 3, (such as fish, sardines and salmon), helps to prevent asthmas symptoms. Asthma is a disease which affects people physically, psychologically and socially as well. Gelfland (2008) writes that its coughing, breathlessness, wheezing and chest tightness affects the wellbeing of the client, limiting their involving in normal day to day activities. He also states that the condition keeps some children from going to school and some adults from work. According to the Australian Centre for Asthma Monitoring or ACAM (2004) 20% of children with asthma report not being involved in any physical activities such as playing and riding bicycles and of feeling anger, frustration and social isolation. Asthmas limiting of activities means life is felt to be more difficult as assistance is needed for activities such as shopping and housework. The National Sleep Foundation (2011) describes how most people with asthma suffer from coughing, wheezing and short of breath in night which prevents them getting enough sleep and makes them more anxious and weak. The effects during an asthma attack can also be serious. Fear and anxiety can rise, even the fear of dying due to the experience of shortness of breath. Fear of an attack can cause constant anxiousness among some asthmatics (University of Chicago Department of Medicine 2007). Asthmas discomfort and stress can also make some persons more aggressive, or to lose control of their lives, leading to less self care in general (University of Chicago Department of Medicine 2007). ACAM (2004) adds that an asthmatic can feel embarrassment over taking their medications and can also develop stress and confusion as they try to understand their asthma. ACAM (2004) also describes an Australian study that showed children and adolescents with asthma having lower self esteem, more behavioural problems, poor physical and mental status and worse sole functioning dimensions than others without it. In addition, asthma can socially isolate people by restricting their participation in social events, limiting their working and other activities, taking more sick days at work and engaging in avoidance behaviour that impairs relationships with family, friends, relatives and colleagues (ACAM 2004). Asthma can also create financial problems due to long term work limitations and decreased education. Sufferers are therefore more likely to experience anxiety, stress and depression (ACAM 2004). Conclusion In conclusion asthma can be described as a chronic respiratory condition which can be identified by breathing difficulty, wheezing, cough and chest tightness. Narrowing and swelling of the airways and increased mucus production are the major episodes looked for to establish an asthma condition. Physical examinations, pulmonary function tests, blood tests and chest X-rays are also used to determine asthma. The medications used to manage asthma long term are symptom preventers and symptom controllers. Symptom reliever medications are used for the immediate control of its symptoms. Inhalation or ingestion of allergens and pollutants, exposure to cold weather, exercises, infections and occupational factors such as dust and chemicals can be considered asthmas risk factors, and healthcare professionals need to provide client education in order to prevent and minimize asthma attacks. Chronic asthma conditions affect client physical, psychological and social wellbeing.

Will Computer Growth Ever Slow Down :: Essays Papers

Will Computer Growth Ever Slow Down It all started in 1930, when Vannevar Bush created what he called a â€Å"differential analyzer† for what amounted to simple calculations (Epstein 919). Who knew then that this simple technology would evolve into something as diverse and complex as it has today? These machines and the plethora of technology that surrounds them continue to be produced and improved upon at a phenomenal, almost break-neck, and somewhat frustrating pace for consumers. We are left to wonder if and when the computer industry will ever slow down; and what are the repercussions if it does not? Will there be any jobs left for the human race? Or perhaps there could be some frightening future in store for us if artificial intelligence gets less artificial and more intelligent. Questions upon questions continue to surface as the computer era continues to rage on, leading to one significant query: will this computer revolution ever slow down? Since the 80’s, a massive shift in our country’s industry has occurred. Almost any and every aspect of this great nation and other nations’ industry has become saturated with computer technology. From automated teller machines, to robots that build our cars for us, every warehouse on earth seems to have an â€Å"electronic buddy† helping their production. Beginning with ideas to assist us and leading to something much greater, we have become dependant on machines to do a great variety of tasks for us. With such enormous human interest and demand for products that will do our work for us, there are companies that will do much of anything to create or I prove upon a marketable product. What is known as one of the largest industries in the world, c9omputers gross†¦(annual net income) Ranking among the car industries of the world, which gross†¦(annual net income) So it would seem that the greatest force pushing this industry is money. And with money companies need to utilize whatever edge is available. In the United States, and other countries alike, that edge would be innovation. With the large amount of college graduates, (computer science majors graduating college) and the occasional genius, these companies have the resources to continually create a great product, keeping ideas as fresh as possible. In part this is why the computers we had a couple of years ago or even a few months ago, are deemed obsolete.

Sir Gawain and the Green Knight :: Sir Gawain and the Green Knight

Sir Gawain and the Green Knight Lines 1372-1453 from The Norton Anthology of English Literature Sir Gawain and the Green Knight was written in the fourteenth century by an anonymous poet who was a contemporary of Geoffrey Chaucer. The story was originally written in a Northern dialect. It tells the story of Sir Gawain's first adventure as a knight. This section of Sir Gawain and the Green Knight pertains to the agreement between Bercilak de Hautdesert, the host, and Gawain. Bercilak is to go hunting in the morning, while Gawain sleeps. Upon the return of Bercilak from his hunting trip, he is to give to Gawain all that he has caught. In return, Gawain is to return all that he has won in his "hunt." They make this bargain three times, at the end of each day. The segment begins with Bercilak showing Gawain the fruits of his hunting trip. Gawain returns the fruits of his "hunt" by bestowing on Bercilak a kiss. The source of the kiss given to Gawain remains anonymous. However, Gawain is not aware that Bercilak knows exactly where and from whom Gawain has received his gift. Sir Gawain and the Green Knight consists of three hunts, three temptations, and three different animals. It is not by accident that the first day's hunt is for deer. The deer represents the innocence and purity of Gawain as a knight. The lengthy and detailed description of the hunt and the capture of the deer serve to emphasize the symbolism of the deer. The even more detailed description of the slaughter and butchering of the meat further emphasizes the symbolism. It can be inferred that the butchering of the deer is similar to the fate that awaits Gawain when he meets with the Green Knight. The next day's hunt is for a wild boar. The fierce animal is symbolic of Gawain's reactions to the increasing advances from Bercilak's wife. The boar is fierce and much more difficult to catch and kill, just as Gawain is steady in his resistance to temptation. Bercilak is aware that Gawain is resistant to all temptation at this point. Gawain is true to his reputation of a chivalrous, worthy knight. The third day's hunt is for the wily and cunning fox. This is symbolic of the clever way that Gawain resists temptation. Sir Gawain and the Green Knight :: Sir Gawain and the Green Knight Sir Gawain and the Green Knight Lines 1372-1453 from The Norton Anthology of English Literature Sir Gawain and the Green Knight was written in the fourteenth century by an anonymous poet who was a contemporary of Geoffrey Chaucer. The story was originally written in a Northern dialect. It tells the story of Sir Gawain's first adventure as a knight. This section of Sir Gawain and the Green Knight pertains to the agreement between Bercilak de Hautdesert, the host, and Gawain. Bercilak is to go hunting in the morning, while Gawain sleeps. Upon the return of Bercilak from his hunting trip, he is to give to Gawain all that he has caught. In return, Gawain is to return all that he has won in his "hunt." They make this bargain three times, at the end of each day. The segment begins with Bercilak showing Gawain the fruits of his hunting trip. Gawain returns the fruits of his "hunt" by bestowing on Bercilak a kiss. The source of the kiss given to Gawain remains anonymous. However, Gawain is not aware that Bercilak knows exactly where and from whom Gawain has received his gift. Sir Gawain and the Green Knight consists of three hunts, three temptations, and three different animals. It is not by accident that the first day's hunt is for deer. The deer represents the innocence and purity of Gawain as a knight. The lengthy and detailed description of the hunt and the capture of the deer serve to emphasize the symbolism of the deer. The even more detailed description of the slaughter and butchering of the meat further emphasizes the symbolism. It can be inferred that the butchering of the deer is similar to the fate that awaits Gawain when he meets with the Green Knight. The next day's hunt is for a wild boar. The fierce animal is symbolic of Gawain's reactions to the increasing advances from Bercilak's wife. The boar is fierce and much more difficult to catch and kill, just as Gawain is steady in his resistance to temptation. Bercilak is aware that Gawain is resistant to all temptation at this point. Gawain is true to his reputation of a chivalrous, worthy knight. The third day's hunt is for the wily and cunning fox. This is symbolic of the clever way that Gawain resists temptation.

History of the internet :: essays research papers fc

History of the internet Introduction The Internet has revolutionized the computer and communications world like nothing before. The invention of the telegraph, telephone, radio, and computer set the stage for this unprecedented integration of capabilities. The Internet is a world-wide broadcasting capability, a mechanism for gathering information, and a medium for communication and interaction between individuals and their computers without regard for geographic location. The Internet represents one of the most successful examples of the benefits of sustained investment and commitment to research and development of information infrastructure. Beginning with the early research in packet switching, the government, industry and academia have been partners in evolving and deploying this exciting new technology. Today, the average person commonly uses terms like ‘mclennox@ilink.nis.za’ and ‘http://lennox.w3.to’. The Internet today is a widespread information infrastructure, the initial prototype of what is often called the National Information Infrastructure. Its history is complex and its influence reaches not only to the technical fields of computer communications but throughout society as we move toward increasing use of online tools to accomplish electronic commerce, information acquisition, and community operations. The Initial Internet Concepts The original ARPANET grew into the Internet. Internet was based on the idea that there would be multiple independent networks, beginning with the ARPANET as the pioneering packet switching network, but soon to include packet satellite networks, ground-based packet radio networks and other networks. In this approach, the choice of any individual network technology was not dictated by a particular network architecture but rather could be selected freely by a provider and made to interwork with the other networks. Up until that time there was only one general method for federating networks. This was the traditional circuit switching method where networks would interconnect at the circuit level, passing individual bits on a synchronous basis along a portion of an end-to-end circuit between a pair of end locations. Kleinrock had shown in 1961 that packet switching was a more efficient switching method. Along with packet switching, special purpose interconnection arrangements between netwo rks were another possibility. While there were other limited ways to interconnect different networks, they required that one be used as a component of the other. In an open-architecture network, the individual networks may be separately designed and developed and each may have its own unique interface which it may offer to users and other Internet providers. Each network can be designed in accordance with the specific environment and user requirements of that network.

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.