Spinozas Theory of Emotions Essay Example

Spinozas Theory of Emotions Paper Christian Scherrer, student number: 013851259 Analysing and synthesizing passions Aspects of Cartesian and Spinozist method It has often been noted that in the third part of his „Ethicsâ€Å" Spinoza follows in his list of definitions of affects to a great extent the one of passions given by Descartes in his â€Å"Passions de lAme† (apart from divergent evaluations of some of the passions1, like Spinoza? s refusal to include admiratio among them). It also appears that both of them are building a taxonomy of passions that introduces some kind of hierarchical order among these. We find both in Descartes as well as in Spinoza a set of passions2 out or by means of which further, in some sense more complex or specific passions are being developed from. What will be my guiding interest in this essay, is to compare and distinguish the two theories of passion according to the sense in which basic or primary passions are named thus and the way they are being discovered or identified and thereby hinting at a difference on the more general level of methodology. I want to begin with what is a starting point in Descartes? and Spinoza? s defining the passions in a general manner. We will write a custom essay sample on Spinozas Theory of Emotions specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Spinozas Theory of Emotions specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Spinozas Theory of Emotions specifically for you FOR ONLY $16.38 $13.9/page Hire Writer It is very interesting and insightful to compare the procedures through which they arrive at their different conceptions of passions and at identifying and defining the basic ones. It is true that they both operate with the notion of causa as a starting point for their distinction between action and passion, but we should draw our attention to what follows and what comes in between their principles of causality and the definitions of the basic affects to rightly appreciate the differ ence in their approaches. In reality, though, we already find important differences in the relational structure between the notions of action, passion and cause. In the very first paragraph of the â€Å"Passions de lAme†, Descartes starts with a very general principle, adopted from other philosophers, which consists in distinguishing within the components of a causal event between two things: an 1 As Spinoza, like Descartes, names several of the defined entities in part III of the „Ethicsâ€Å" „passionsâ€Å", except from those actions whose „adaequata possimus esse causaâ€Å" (see EIIID3), I will subsequently continue to talk about pas sions, without differentiation between their being cartesian or spinozist, where this distinction by Spinoza can be applied. The references in my quotations from Spinozas â€Å"Ethics† I will always abbreviate with â€Å"E†, followed by roman num bers for the respective part, then the letters â€Å"D† for â€Å"definitione†, â€Å"P† for â€Å"propositio† plus the respective arabic numbers, â€Å"Sch† for â€Å"scholium†, â€Å"Cor† for â€Å"corollarium† etc. References to the â€Å"Passion de lAme† will be abbrevi ated by â€Å"P† plus â€Å" §Ã¢â‚¬  and the respective number of the paragraph. Also here it is adequate to speak only of passions in Spinoza`s use or the term because indeed in part 3 of the Ethics we find such affects that are derived from tristitia (which is always a passion) and laetitia only as far as „in nobis aliquid fit vel ex nostra natura aliquid sequitur, cujus nos non nisi partialis sumus causaâ€Å" (EIIID2), which means being passive. Whether kinds of active joy or even such with compon ents of passive joy can be derived from the basic affects is another question and we will shortly come back on this again. Christian Scherrer, student number: 013851259 active and a passive part in relation to which one and the same event may be called either an action or a passion. So in every single case that falls under this kind of structure we necessarily have one active and one passive component that will determine the perspective on the event relating them and decide whether it is an action or a passion. In Spinoza, on the other hand, we find a completely different structure in the relational field among these notions and we may suppose that this will have consequences on his further proceeding. First we have to consider that for Spinoza it is not enough or even wrong to say of a thing that it is active or acting insofar as it is producing an effect on some other thing. Instead, he is connecting the property of being active to self causality, when he writes in part I that God alone, as a free cause, exists and acts solely out of the necessity of his own nature 3. As God is not only causing all the finite modes but unlike these and primarily himself, it would be absurd to say that he is therefore active and passive at once. Thus, we somehow find the paradigm for activity in God? s self-causation. This also means that we can only define action and passion in their meaning for human beings in a different, more specific sense, namely, characterized as affections (and their ideas) that either augment or diminish some body? s potentia agendi. Compared to Descartes then, we also get a different idea of cause and effect, as they are not in every case identifiable as one active and one passive component connected through some affection that is always action and passion at the same time; rather, insofar as we are the adequate cause of this affection in us it is an action and we can be called active, whereas insofar as we are only an inadequate and partial cause of some affection in us we suffer a passion and are passive 4. So, what is a passion and what an action is less seen in relation to a cause and it? s effect as the one acting on the other, but rather in relation to a contextual or local conception of cause. It seems that one and the same affection can be seen in Spinoza? s thinking as action and passion at once just in case that it can be achieved to conceive of the cause in question (an idea for example) as at the same time adequate and inadequate concerning the scope that the idea of this cause comprises 5. As God can never be conceived of as 3 See EIP17Cor I and II. There is of course a very delicate aspect about the use of the words „inâ€Å" and „extraâ€Å" when Spinoza for example writes: „Nos tum agere dico, cum aliquid in nobis aut extra nos fit, cujus adaequata sumus causa ( )â€Å" (EIIID2). One might ask in what sense there can be effects outside of us insofar as we (our ideas, the affections of our body) have to be seen as their adequate causes without which the effect can not be conceived of nor exist (see EIID2, where „es senceâ€Å" is defined which is not easy to distinguish from an adequate cause). What one can follow along such considerations is a certain expansive trait in Spinoza? s theories of body and mind. 5 Therefor Spinoza writes in EIIIP1: „Further, whatever necessarily follows from an idea which in God is adequate, not insofar as He not only comprises the mind of a single man, but also the minds of other things together with the mind of this man, of this [†¦] the mind of this man is not the adequate, but the partial cause, and therefor (according to definition 2 of this part), insofar as the mind has inadequate ideas, it necessarily suffers some things. (Mind that all the English quotations from primary literature will be my translations from the original language (in this case Latin) with support drawn from the respective German translation, which is due to my lack of English edition at the time of writing this essay. ) 2 Christian Scherrer, student number: 013851259 partial cause of himself, he can only be thought of as active. A changing from passion to action in a mode is not being accomplished then by changing the direction in the relation between cause and effect, but by changing the affective condition of the mode by expanding it and transforming it to an adequate cause of the affect that has been a passion. I would like now to concentrate on the two philosophers proceeding in establishing the basic passions; and here I think we can observe some important features that can help us to recognize the pe culiarities of their methodologies which are commonly referred to as analytic in Descartes? ase and geometrical or synthetic in Spinoza? s. Unlike Spinoza, who gives us a ready definition of affects that already includes the two possible versions of them (actions and passions) in the beginning of part III after not even having mentioned them in the preceding text 6, Descartes first has to go through a long process by employing his general principle of action and passion to the relationship between body and soul to arrive at a defini tion of passions. After distinguishing what we can find as the soul? s and the body? proper functions and he makes us realize that there is a number of mental functions that could rightly be called passions of the soul; namely all those perceptions or cognitions (P §17: â€Å"toutes les sortes de perceptions ou connoissances†) which have the body as their cause and not the soul itself (see P §19). Then he goes on to distinguish different sorts of such perceptions among themselves, relying in every step of analysis on criteria of how their formation dependence from soul or body or if they show a relation to a notable and determinate perceptual cause that has been transmitted to the soul by nerves 7. Among the latter sort of perceptions, he again distinguishes and at last finds to which the name â€Å"passions of the soul†, following an ordinary restriction in the use of the expression, can be applied8, defining them in a general manner as follows: â€Å"After having considered in what the passions of the soul differ from all the other thoughts, it seems to me that one can generally define them as perceptions or sentiments or emotions of the soul which particularly referred to her, and which are caused, maintained and fortified by some movement of the animal spirits. (P §27) 6 Apart from one rather nontechnical occurrence in part one and one very general reference to affects as â€Å"modi cogit andi† in the third axiom of part two. 7 See P §21: â€Å"Or encore que quelques unes de ces imaginations soient des passions de lame, en prenant ce mot en sa plus propre plus particuliere signification; quelles puissent estre toutes ainsi nommees, si on le prend en un e signification plus generale: toutefois, pource quelles nont pas une cause si notable si determinee, que les perceptions que lame recoit par lentremise des nerves (†¦), il faut considerer la difference qui est entre ces autres. 8 See P §25: â€Å"Or encore que toutes nos perceptions (†¦) soient veritablement des passions au regard de nostre ame, lors quon prend ce mot sa plus generale signification: toutefois on a coustume de le restreindre a signifier seulement celles qui se rapportent a lame mesme. Et ce ne sont que ces dernieres, que jai entrepris icy dexpliquer sous le nom de passions de lame. † 3 Christian Scherrer, student number: 013851259 We can already see in this process that, what Descartes does, is a systematic and methodical analysis of notions that we usually do not understand properly. We are aware that there is something in each of us that we commonly call passions. But we do not, until now, really understand what they are, in what they consist, how they come about, etc. So if we want to understand our passions, just like with all the other phenomena that our scientific mind can be concerned with, we in the end need to understand their causes. In his monography â€Å"Expressionism in Philosophy, Spinoza†, Gilles Deleuze characterizes Descartes? analytic method as a process of rendering on the basis of clear and distinct ideas of effects the initially confused ideas of their causes clear and distinct. One can even say that the clear and distinct knowledge of a cause depends on the clear and distinct knowledge of its effect9. Spinoza, opposing these basic ideas in Descartes method, conceives of the right way to attain to real knowledge in an entirely different way in thinking that we always have to proceed from adequate ideas of some causes to adequate ideas of their effects and that the former consist in definitions that are appropriate for expressing the essence of this cause and also involve already the essence of its effects. So we can see how from Spinoza? s point of view the whole procedure of Descartes tries to go in a wrong direction. What has to be done first in Descartes method is not to elaborate a definition that adequately expresses the essence of the cause of the things that we want to explain and get to know, but to attain to clear and distinct ideas of those things whose causes we subsequently want to discover, â€Å"and thence show that the effect would not be what we know it to be, did it not have such a cause on which it necessarily depends†10. In Descartes? iew, the synthetic method is nothing more than a way of demonstrating a proof what has been found by means of the analytic method that has the disadvantage of not demonstrating the concrete way in which we really attained to the demonstrated knowledge, how effects really depend on their causes (which can only be achieved by analytic demonstration) and only has the merit of expositing the strict dependency of the propositions befo re discovered11. So, if Descartes demands starting with elaborating a clear and distinct idea of the effect that we want to examine, we can see now how he attains to this in the first part of the â€Å"Passions de lAme†. Descartes speaks of the causes of our perceptions with a different interest before in part two he starts to develop the particular definitions of the single passions. First his aim appears to be exactly to form a clear and distinct idea of the passions in a general sense concerning which the main prob9 See Deleuze, Gilles: â€Å"Expressionism in Philosophy, Spinoza†, pp. 155-156 10 Ibid. , p. 156. In a footnote to this sentence, Deleuze quotes Descartes third meditation to give an example that is apt to show the extreme difference to Spinoza? method: â€Å"I recognize that it would not be possible for my nature to be as it is, that is, that I should have in myself the idea of God, did not God really exist. † 11 See Deleuze, Gilles: â€Å"Expressionism in Philosophy, Spinoza†, p. 159; Roth, Leon: â€Å"Spinoza and Cartesianism (II)†, p. 161 4 Christian Scherrer, student number: 013851259 lem seems to be that we usually feel our passions like effects in our soul itself, without seeing any proximate (physical or nervous) cause 12. Only by distinguishing them from the other (passive) perceptions we can have a clear and distinct idea of our passions in general. But in part two Descartes explains that for gaining knowledge of the particular passions this knowledge of the proximate physical cause (some particular movement in the pineal gland) will not suffice and that instead we have to ask for their first cause in order to distinguish the single passions. But, having in mind that Descartes wants to proceed from clear and distinct ideas to their causes and render them clear and distinct as well, the question seems to be again: How can we find the causes of the single passions, if we dont have a clear and distinct idea of them yet? And: Do we not need first the causes of the single passions in order to be able to distinguish them and see them clearly? How do we, so to say, fill the gap which is lurking here? But, as we can see in  §51, there is really a priority of the knowledge of effects over the knowledge of their causes, as Descartes writes: â€Å"( ) still it can be inferred from what has been said that all of these passions can be aroused by the objects that move the senses, and that these objects are their most common and principal causes: from this it follows that, for finding them all, it is sufficient to consider all the effects of these objects. In the next paragraph Descartes specifies that we have to consider, in enumerating and ordering the effects (the passions) in the soul, nothing than the different manners in which their causes have importance or are useful for us, and these manners we can find in the effects themselves before we can know their exact (physical) causes. After having distingu ished the single passions we then can go on to infer their exact causes and define them in a precise way. It is important to notice that the â€Å"passions principales† that Descartes enumerates in the beginning of the second part correlate to the clear and distinct ideas of the effects through which we want to infer their necessary causes, but that there is an additional step in between. It is actually the conclusion from a reduction along these preliminary characterizations to the six passions that are recurring in these everywhere to the reduction to physical causes through which we will be able to explain especially those â€Å"simple primitives† passions, which gives us the sense in which they are conceived as simple and primitive. According to Descartes, we do not need and will not find an independent, distinct cause for each of the principal passions, but as we saw that some of them are contained in the clear and distinct ideas of others and that those few together cover all of them, it will be sufficient to discover their causes alone. The explanations of the â€Å"passions particulieres† (at least in their physiological part) will depend solely on them. Even more, Descartes seems to infer that these six 12 See P §25: â€Å"Les perceptions quon raporte seulement a lame, sont celles dont on sent les effets comme en lame mesme, desquelles on ne connoist communement aucune cause prochaine, a laquelle on les puisse raporter. † 5 Christian Scherrer, student number: 013851259 basic passions are also â€Å"primitive† in a developmental psychological sense when he is tracing back the specific movements of the blood and animal spirits while feeling love, hate, joy, sadness and desire to first experiences of basic physiological processes in the soul after being connected with the body. Thus, the â€Å"primitive passions† are also more primitive as they occur first in every individuals life (see P §Ã‚ §107-111). And in a third sense they are primitive or simple as they can be conceived as simple or pure when we think of their initial occurrences in an individual and also the possibility of their being isolated from certain inclinations and dispositions or their combination/mixture with other primitive passions 13. So, we can read in  §82 about the different kinds of love that, if freed from all desires to possess, the love of a father to his children is pure, as well as can be (especially) admiratio and the other primitive passions. Thus Descartes â€Å"passions particuliers† are found to be complex, secondary passions as a result of his analytical or reductive method: First, they are explainable by means of the definitions or causes of the simple passions. Secondly, they develop in the process of experiences, in the interaction between body and soul out of the primitive passions. Thirdly, they are always mixed out of simple passions, they are their proportions in addition to certain physical inclinations and provoked by cer tain ideas. So, how does Spinoza arrive at defining primary passions and and how does he relate further ones to them? What are the principles behind his taxonomy? As we know, Spinoza does not use the concept of affect in a significant way before his definition in the beginning of the third part. This seems strange and dissatisfying from the perspective of Descartes` method. Does Spinoza just invent a definition? But as inventing does not at all appear like a methodical step in an inquiry, there seems to be a arbitrary element14. There are no conceptual analyses by means of relevant distinctions and no inferences of proximate or first causes from ideas that we can perceive clearly in our mind. What is rather the source for the general definition of affects in part three, the ground on which it rests, is Spinoza`s theory of mind and body, developed in the preceding part, whose major characteristic is its parallelism and which again has its origin in the metaphysics of substance mon 13 Indeed we find in most of the definitions of the particular passions in the third part of the â€Å"Passions de lAme† either an explanation through a certain inclination or disposition of the soul which are caused by a certain movement of the animal spirits in the brain that leave impressions which in return reinforce certain ideas that we form about an object (like in the case of esteem and disdain: see P §149). On the other hand there are those passion that are defined as mixtures of the movements that cause one or the other primitive passion (like in the case of hope and fear: see P §165) 14 See chapter 4 in Jonathan Bennett? s â€Å"A Study of Spinoza? s Ethics†, where he criticizes Spinozas geometrical method as highly self-referential or idiosyncratic and therefore not well founded. I believe that he is misinterpreting what Spinoza himself saw as the merits of his method, on which his â€Å"Tractatus de intellectus emendatione† can shed some light. 6 Christian Scherrer, student number: 013851259 ism in part one. Contrary to Descartes in the â€Å"Passions†, he therefore does not grasp an idea, like passion, action, perception and the like, to subsequently try through a process of analysis to arrive at an adequate definition of this concept by distinguishing it from other ideas; but really begins from his definition of substance, God, or Nature, from which he attempts to show that everything else follows. In the â€Å"Tractatus de intellectus emendatione†, Spinoza stresses that in attaining knowledge through a right method we can only proceed from causes to effects 15 and that we have therefore to start with the best definitions of what we take as a cause: â€Å"Quare recta inveniendi via est ex data aliqua definitione cogitationes formare: quod eo felicius et facilius procedet, quo rem aliquam melius definiverimus. †16. According to this, Spinoza`s way can be described rather like a productive process of construction (truly reminding of the geometrical sense) in which the developed figures are a posteriori given names that have already been familiar to us, like â€Å"action† and â€Å"passion†, â€Å"joy† and â€Å"sadness†. He is less looking for their appropriate content, but rather encounters or meets proceeding along the axioms, definitions and laws that he establishes by and by, and thus with a method – the true natures of those things of which we have always had only inadequate ideas. We can very well observe this procedure in how Spinoza arrives at his definitions of the basic af fects and we can also try to rightly understand the sense in which they are primitive or primary and the others composite or deduced. The crucial step in developing something that can bear the name â€Å"affect† is maybe, when in EIIIP4 first we find the proof (based on evidence) that a thing can only be destroyed by an external cause and then in EIIIP6, Spinoza concludes that, as nothing contrary to a subject? s existence can be part of it, there has to be a strive for self-perseverance in every thing according to its own nature. It is the conscious idea of this strive which explains our first basic affect: desire (cupiditas). The deduced strive for self-perseverance, named conatus, then also serves as the concept by which our two other primary affects can be understood: an alteration in our mind that conforms to our conatus will be called joy (laetitia), while an alteration opposed to it will be called sadness (tristitia). We should note here that between desire on the one hand and joy and sadness on the other there seems to be a certain difference, as Spinoza calls the latter ones in the same passage where he defines them â€Å"passiones†, whereas the former is first characterized only as affect and in 15 See the â€Å"Tractatus de intellectus emendatione†: â€Å"Nam revera cognitio effectus nihil es, quam perfectiorem causae cognitionem acquirere. (†¦) Sed optima conclusio erit depromende ab essentia aliqua particulari affirmativa, sive a vera et legitima definitione. †, p. 70; and also Deleuze, Gilles: â€Å"Expressionism in Philosophy, Spinoza†, pp. 157f. An important aspect is that Spinoza correlates a legitimate and true definition to an affirmative essence. There we can see that defining a certain thing can not consist in showing difference to another thing, be it even an essential difference, but only in affirming its positive essence. 16 Spinoza: â€Å"Tractatus de intellectus emendatione†, p. 70 7 Christian Scherrer, student number: 013851259 deed it seems difficult to conceive of how desire, as being the conscious idea of our conatus could be a passion. But Spinoza will specify (in EIIIP58 f. ) that joy as well as desire must and indeed only they can be called active insofar as their cause consists in an adequate idea. So, although desire might be taken somehow to follow from the two other basic affects, expressing rather a current condition of our mind than a transition into a different state of perfection, the guiding distinction that accounts for Spinoza? exclusive occupation with definitions of passions in part three, separates active desire and joy from passive desire, joy and sadness. Spinoza tells us in the same paragr aph in which he is introducing joy and sadness that he is acknow ledging only these along with desire as the three primary passions and that he will show how all the remaining originate in them 17. But how exactly does he achieve this? The main means which will allow him to account for a diversity of passions will be certain mechanisms or – better – dispositions of the mind by which it is urged to behave in a certain way and to proceed from one idea or one affect to another. The main enetic principles guiding the deduction of the variety of passions in part three are those of attribution of causality (through which love and hate are being defined), associ ation of affects (we can suffer a certain affect just because it has regularly accompanied another one, by which we are affected now, in the past), similarity (unknown things can cause affects in us simply because of their similarity to things we have already been affected by) and imitation (insofar as we have an idea of something similar to us suffering an affect, we will be naturally brought to suffer the same)18. Of great effectiveness are also Spinoza? s assumptions about how the mind will behave in reaction to certain ideas (for example to exclude the existence of a thing which is thought of as the cause of our sadness). These principles seem to suffice to develop the same variety of passions as have been defined by Descartes. But, as we have seen, there is obviously a significant difference between the two methods insofar as Spinoza, so to say, meets our common notions for passions on the way and annexes or almost usurps them for his purposes. The main focus about his method is on the deductive and genetic force of his concepts and definitions. This is why we often have to realize that, in spite of their relative conformity with how we would intuitively describe what our passions consist in, Spinoza is giving quite unconventional definitions that would maybe not convince us if taken out of the context of their interrelation. It is therefore not surprising that in several passages we find con 17 See EIIIP3: â€Å"( ) et praeter hos tres nullum alium agnosco affectum primarium: nam reliquos ex his tribus oriri in seqq. ostendam. † 18 See Renz, Ursula: â€Å"Spinoza: Philosophische Therapeutik der Emotionen†, pp. 322-327. 8 Christian Scherrer, student number: 013851259 iderations concerning the relation between his definitions and our common language for emotions, an aspect that is not at all as noticeable in Descartes because of his analytic approach that allows him to use our common language already before att aining to the knowledge of those phenomena we do have words for. Most remarkably, Spinoza admits that in defining the most important passions he does not want or can not (for some reason which might be very interesting to ask for as an explana tion of this fact) detach himself completely from the usual meanings of the names he adopts: â€Å"Haec nomina ex communi usu aliud significare scio. Sed meum institutum non est verborum significationem, sed rerum naturam explicare easque iis vocabulis indicare, quorum significatio, quam ex usu habent, a significatio, qua eadem usurpare volo, non omnino abhorrent, quod semel monuisse sufficat. † (EIIIDef. XX) On the other hand there is more than one passage in which seems to be completely indifferent to wards any affinities between his definitions and common meanings, as he repeatedly asserts that we can find much more affects than we have words for: â€Å"Et ad hunc modum concipere etiam possumus odium, spem, securitatem et alios affetus admirationi junctos; atque adeo plures affectus deducere poterimus, quam qui receptis vocabularis indicari solent. Unde apparent affectuum nomina inventa esse magis ex eorum vulgari usu quam eorundem accurata cognitione. † (EIIIP52Sch) Here again, it is significant that Spinoza talks of deducing an indefinite number of affects, while Descartes talks about distinguishing (see P §68). We also find the awareness in Descartes that he uses the general and particular words for our passions in a different way than we usually do (which seems always to go along with elaborating a theory). It may as well be supposed that Descartes ex pects there to be new combinations of the primitive passions that might lack a correspondent name in our ordinary language. But my comparison should have shown that the idea about generating new passions is of completely different kind than in Spinoza`s theory. Bibliography Beaney, Michael: Analysis, in: The Stanford Encyclopedia of Philosophy (Summer 2009 Edition), Edward N. Zalta (ed. ), URL = . Bennett, Jonathan: A Study of Spinoza? s Ethics, Cambridge: Cambridge University Press 1984. Christian Scherrer, student number: 013851259 Deleuze, Gilles: Expressionism in Philosophy: Spinoza, New York: Zone Books 1990. Descartes, Rene: Die Leidenschaften der Seele, Hamburg: Felix Meiner 1984. Renz, Ursula: Spinoza: Philosophische Therapeutik der E motionen, in: Klassische Emotionstheori en – Von Platon bis Wittgenstein, Hilge Landweer Ursula Renz (ed. ), Berlin/New York: Walter de Gruyter 2008. Spinoza, Baruch de: Opera/Werke, zweiter Band (Tractatus de Intellectus Emendatione/Ethica), Darmstadt, Wissenschaftliche Buchgesellschaft 1978. Spinoza, Baruch de: Ethik in geometrischer Ordnung dargestellt, Hamburg: Felix Meiner 2007. 10

Advice From an Energy-Efficient Architect

Advice From an Energy-Efficient Architect The most energy-efficient houses function like living things. They are designed to capitalize on the local environment and to respond to the climate. Australian architect and Pritzker Prize-Winner Glenn Murcutt is known for designing earth-friendly homes that imitate nature. Even if you live far from Australia, you can apply Glenn Murcutts ideas to your own home-building project. 1. Use Simple Materials Forget the polished marble, imported tropical wood, and costly brass and pewter. A Glenn Murcutt home is unpretentious, comfortable, and economical. He uses inexpensive materials that are readily available in his native Australian landscape. Notice, for example, Murcutts Marie Short House. The roof is corrugated metal, the window louvers are enameled steel, and the walls are timber from a nearby sawmill.   How does using local materials save energy? Think of the energy used beyond your own home- what fossil fuels were burned to get supplies to your work site? how much air was polluted to create cement or vinyl? 2. Touch the Earth Lightly Glenn Murcutt is fond of quoting the Aboriginal proverb touch the earth lightly because it expresses his concern for nature. Building in the Murcutt way means taking special measures to safeguard the surrounding landscape.   Nestled in an arid Australian forest, the Ball-Eastaway House in Glenorie, Sydney NSW, Australia hovers above the earth on steel stilts. The main structure of the building is supported by steel columns and steel I-beams. By raising the house above the earth, with no need for deep excavation, Murcutt protected the dry soil and surrounding trees.   The curved roof prevents dry leaves from settling on top. An exterior fire extinguishing system provides emergency protection from forest blazes that are so prevalent in Australia. Constructed between 1980 and 1983, the Ball-Eastaway house was built as an artists retreat. The architect thoughtfully placed the windows and meditation decks to create a sense of seclusion while still providing scenic views of the Australian landscape. The occupants become part of the landscape. 3. Follow the Sun Prized for their energy efficiency, Glenn Murcutts houses capitalize on natural light. Their shapes are unusually long and low, and they often feature verandas, skylights, adjustable louvers, and movable screens. Horizontal linearity is an enormous dimension of this country, and I want my buildings to feel part of that, Murcutt has said. Notice the linear form and expansive windows of Murcutts Magney House. Stretching across a barren, wind-swept site overlooking the ocean, the home is designed to capture the sun. 4. Listen to the Wind Even in the hot, tropical climate of Australias Northern Territory, houses by Glenn Murcutt do not need air conditioning. Ingenious systems for ventilation assure that cooling breezes circulate through open rooms. At the same time, these houses are insulated from the heat and protected from strong cyclone winds. Murcutts Marika-Alderton House is often compared to a plant because the slatted walls open and close like petals and leaves. When we get hot, we perspire, says Murcutt. Buildings should do similar things. 5. Build to the Environment Every landscape creates different needs. Unless you live in Australia, you are not likely to build a house that duplicates a Glenn Murcutt design. You can, however, adapt his concepts to any climate or topography. The best way to learn about Glenn Murcutt is to read his own words. In the slim paperback Touch This Earth Lightly Murcutt discusses his life and describes how he developed his philosophies. In the words of Murcutt: Our building regulations are supposed to prevent the worst; they in fact fail to stop the worst, and at best frustrate the best- they certainly sponsor mediocrity. I’m trying to produce what I call minimal buildings, but buildings that respond to their environment.† In 2012 Great Britains Olympic Delivery Authority (ODA) rigorously used sustainability principles similar to Murcutts to develop Olympic Park, now called Queen Elizabeth Olympic Park. See how this urban revitalization happened in How to Reclaim the Land - 12 Green Ideas. In light of climate change, why cant our institutions mandate energy efficiency in our buildings? In Glenn Murcutts Own Words: Life is not about maximizing everything, its about giving something back - like light, space, form, serenity, joy.- Glenn Murcutt Touch This Earth Lightly: Glenn Murcutt in His Own Words ​​Source: Biography by Edward Lifson, Director of Communications, The Pritzker Architecture Prize (PDF) [accessed August 27, 2016]

The Role of Religion in Kwame Appiahs analysis Essay

The Role of Religion in Kwame Appiahs analysis - Essay Example One principle that Appiah beholds is the existent of a commonality in all human beings despite the various cultural backgrounds and is responsible for the diversity in the world. Case in point, Appiah demonstrates how his experience with a Ghanaian festival resonates with the attributes of a celebratory environment and feeling over the world in different festivals. Appiah explains that each culture has its own festival and one other worldwide event that appears to make a difference in non-existent culture is globalization. In this regard, Appiah identifies globalization’s main objective as promotion of commonness while getting rid of divisions amongst the world’s citizens. Appiah’s analysis has a religious perspective too. In one instance, Appiah identifies the role of Cosmopolitanism in elimination of what is morally wrong. In this regard, Cosmopolitanism plays the same role as religion would in the world. This expose elucidates the role of religion in Appiahâ⠂¬â„¢s analysis while comparing his approach to my approach. Appiah identifies globalization as an event each individual in the world identifies with. In this regard, he further identifies that the role of globalization is to make the one solid unit where people eliminated the divisions between them and embraced each other as one common people despite their race, religion, and ethnic affiliations. In addition, this commonness in people, as promoted by globalization, should exist regardless of different heritages. The roles of religion while Appiah carried out his analysis is that, religion enabled individuals acquire a global perspective (Livingston). In this regard, a global perspective amongst individuals enabled them to view the world as one homogenous group regardless of the different cultures and religions different people and individuals practiced. Appiah’s approach is not different from in regards to homogeneity of people through globalization. My approach to globalization is that, regardless of the different religions practiced in the word, people are one homogenous group since the role of religion is to enable individuals view others as one homogenous group. However, Appiah identifies people’s fear that the magnitude of globalization in the world posed a challenge whereby western civilization could greatly affect cultural diversity. Nevertheless, he analyses the situation and puts it that the right approach involves taking individuals as the appropriate object of moral apprehension instead of a nation or a particular plan. In this regard, religion plays a role in Appiah’s analysis in that, religions identifies each person as independent of a group regardless of what binds the groups together in this case religion being the common link. In addition, judgment will be passed to a person on an individual capacity (Livingston). This is true of the role of religion in that, an individual is independent of the religion, or creed they practiced. In addition, religion notes that we are humans. In ef fect, we think and reason as individuals and not as societies or as collectives on what is morally right or wrong. This approach is similar to my approach of life that there is nothing like collective thinking. In addition, each individual is responsible for their own actions that are independent of the creed they practiced and their society. Appiah notes that Cosmopolitan, denotes a citizen of this world and further acknowledges that each one of us has a responsibility over the other individual. In addition, it means that it is all right for us to be different but have differences in ideals while acknowledging that we are responsible for each

Cutco corporation Case Study Example | Topics and Well Written Essays - 500 words

Cutco corporation - Case Study Example Proper marketing is very important in making sure that information reaches the appropriate target group and gives appropriate information about the organization and what it is about. The situation analysis gives information that the cooperation may require to take on a different form of advertisement. Considering a SWOT analysis of the situation combined with the 5Cs of marketing the following can be concluded. The method of advertisement that is currently in used is based on basic factors. One of this methods is the use of social media to advertisement is the use of social media in order to recruit sales persons and gain more customers. This method helps others become aware of the Cutco Company and how their products are helpful. However, there needs to be a clearer description of the material they sell and their use. What is highly required is that the organization is able to balance between the use of directness and the promotions of their cutlery to other unknown regions. There needs to be brand recognition among the alternatives offered before the customer. Factors such as brand personality are very important in establishing an emotional connection between the customer and the particular product that they need. Therefore, the Cutco Company should attempt to find a method that will enable their product lead to a sort of connection to their customers. This will promote the attachment that the customers will have with their products and even lead to more sales for the company. The chosen alternative is much helpful to the organization in that for one, they will have earned the loyalty of the customers. Therefore, each time the customer goes to purchase cutlery, they will prefer the cutlery made by this company. The other factor is that promoting brand personality will also promote the awareness about this product as people recommend to each other the cutlery by this company. As a result, there will be more sales and more revenue being earned by the

Nursing research Essay Example | Topics and Well Written Essays - 250 words - 37

Nursing research - Essay Example In effect, a higher proportion of BSNs reduces the risks associated with child mortality. It is evident that different organizations and licensure guide professionals in their practice. In effect, some of the guidelines may appear unfair since the guidelines may require different approaches to perform a similar task in different professions. For example, double-checking medicine is more emphasized in nurses than  it is emphasized to doctors. While this practice may seem unfair, it is important to point out that the requirement, which might appear unfair to nurses, is put in place only to ensure the delivery of quality services to patients. On the other hand, it is evident that doctors and nurses undergo different training in med school and nursing school respectively with doctors training being more  intense  than the training for nurses. Hence, the requirement to double-check medicine has a basis on the training that these two different professionals

Internet Protocol Version 4 Analysis

Internet Protocol Version 4 Analysis Chapter 2: Literature Review 2.1 Introduction Multimedia streaming over internet is getting its revolutionary in the communication, entertainment and interactive game industries. The web now becomes a popular medium for video streaming since the user does not have to wait to download a large file before seeing the video or hearing the sound. Instead, the media is sent in a continuous stream and is played as it arrives. It can integrate all other media formats such as text, video, audio, images and even live radio and TV broadcasts can all be integrated and delivered through a single medium. These applications may require in terms of bandwidth, latency and reliability than traditional data applications to support the growth of multimedia technology in the future [1]. The transportation of multimedia traffic over networks become more complicated because multimedia is becoming cheaper and cheaper and therefore used more and more. Problems with bearing multimedia flows on networks are mainly related to the bandwidth they require and to the strict maximum delay requirements that must be met [2]. This is important when multimedia applications have to provide users with real-time interaction. Because of the rapid growth of Internet usage and the requirement of different applications, the IPv4 is no more relevant to support the future networks. Many new devices, such as mobile phones, require an IP address to connect to the Internet. Thus, there is a need for a new protocol that would provide new services. To overcome to these problems, a new version of Internet Protocol has been introduced. This is called Internet Protocol next generation (IPng or IPv6), which is designed by the IETF [3] to replace the current version Internet Protocol, IP Version 4 (IPv4). IPv6 is designed to solve the problems of IPv4. It does so by creating a new version of the protocol which serves the function of IPv4, but without the same limitations of IPv4. IPv6 is not totally different from IPv4. The differences between IPv6 and IPv4 are including in five major areas which is addressing, routing, security, configuration and support for mobile devices [4]. Like all the development and new inventio ns, the problems of current Internet Protocol made researcher to develop some new techniques to solve these problems. Even they have tried to make some changes on the current protocol, these changes still didnt help a much. So, at the end the way came to development of a new protocol which is known as IPv6 or IPng. 2.2 OSI 7 Layer Computer networks are complex dynamic systems and difficult task to understand, design, and implement a computer network. Networking protocols need to be established for low level computer communication up to how application programs communicate. Each step in this protocol is called a layer and divided into several layers simplifies the solution. The main idea behind layering is that each layer is responsible for different tasks. The Open System Interconnection (OSI) Reference Model defines seven layers [5]. Physical Layer. This layer deals, for instance, with conversion of bits to electrical signals, bit level synchronization. Data Link Layer. It is responsible for transmitting information across a link, detecting data corruption, and addressing. Network Layer. The layer enables any party in the network to communicate with each other. Transport Layer. It establishes reliable communication between a pair in the system, deals with lost and duplicated packets. Session Layer. This layer is responsible for dialogue control and changing. Presentation Layer. The main task of this layer is to represent data in a way convenient for the user. Application Layer. Applications in this case include Web browsing, file transferring, etc. The Network Layer is the layer that is the most interesting in the context of this project. The following section gives a better view of this layer. 2.3 Network Layer As was mentioned before, this layer is responsible for enabling the communication between any party. The most used method for transporting data within and between communications networks is the Internet Protocol (IP). 2.3.1 Internet Protocol IP is a protocol that provides a connectionless, unreliable, and best-efforts packet delivery system. More details on these network service types are given below [5]. In a connectionless model the data packets are transferred independently from all others and containing full source and the destination address. It is worth mentioning that another type is the connection oriented model. However, the connection-oriented model and its details are beyond the scope of this project and thus will not be pursued in this report. The reader can consult [5] for further information on this type of service. Unreliable delivery means that packets may be lost, delayed, duplicated, delivered non-consecutively (in an order other than that in which they were sent), or damaged in transmission. 2.4 Internet Protocol Version 4 As we know, IPv4 is the current protocol for communication on the Internet. It is the protocol that underlies most communication on networks today, such as TCP/IP and UDP/IP. The largest weakness of IPv4 is its address space [7]. Each IPv4 address only have 32 bits and consists of two parts, defined as network identifier and host identifier [5]. A standard method of displaying an IPv4 address is as decimal value of four octets, each separated a period, for example: 192.168.2.5. Traditionally [6], IP addresses are presented by classfull addressing. 5 classes of address were created, which is A to E. Class A consists of 16,777,214 hosts while class B consists of 65,534 hosts and class C consists of 254 hosts. Class D is reserved for use with multicasting and class E is a block of IP addresses reserved for future use [7]. The class D and E addresses are not used to address public host, so this leaves the rest of the entire range of IP addresses carved up into classes A C. As soon as a site is connected to the Internet, it needs to be given an entire class C. Assuming that many sites only need one or two addresses then this waste over 200 addresses. Once a site reaches over 254 full addressable machines it would need an entire class B, which would waste over 65,000 addresses and so on. This allocation system is obviously insufficient and wastes much of a limited resource. 2.4.1 Header Header is a part of the IP packet[5]. There is a number of fields in an IPv4 header. Below are the some explanations for each field. 2.4.2.1 Version This field (4-bit long) is used to determine the version of IP datagram that is considered. For IPv4 it is set to 4. 2.4.2.12 Internet Header Length (IHL) The Internet Header Length is the length of the header. 2.4.2.3 Type of Service Theoretically, this field (1 octet long) should indicate something special about the protocol. However, it has never really been used. 2.4.2.4 Total Length Total is the length of data in the fragment plus the header. 2.4.2.5 Identification This field is useful for fragmentation only. Its purpose is to enable the destination node to perform reassembly. This implies that the destination node must know which fragments belong to each other, i.e. the source, destination, and protocol fields should match. 2.4.2.6 Offset Offset indicates the point at which this fragment belongs in the reassembly packet. The field is related to fragmentation mechanism and has similar vulnerabilities as the identification field. 2.4.2.7 Time to Live TTL measures the time duration of the datagram presence in a network. This guarantees that no datagram exists forever in the network. 2.4.2.8 Protocol This field identifies the transport protocols, for example UDP or TCP. Since the field contains an arbitrary value that indicates some protocol, encapsulation of one datagram into another (IP tunneling) is possible. 2.4.2.9 Header Checksum The checksum is used to detect transmission errors. However, this field was removed in IPv6. 2.4.2.10 Source Address. This field specifies the source address. 2.4.2.11 Destination Address The destination address (4 octets long) is specified in this field. No attacks related to this field are known. 2.4.2.12 Options The field (variable size) was designed to improve the IP communication. There are several options defined for this field. Among them are: security, source routing, and route recording. 2.4.2.13 Padding The field (variable size) is used to fill the IP header with zeros if the header length is less than 32 bits. 2.5 Internet Protocol Version 6 IPv6 is a new version that is specified in RFC2460 [5] to overcome the weakness of the current protocol in certain aspect. It uses a 128 bit long address field which is 4 times longer than Ipv4 addresses. This size of address space removes one of the worst issues with IPv4 and IPv6 doesnt have classes of addresses. In general, IPv4 and IPv6 have a similar in their basic framework and also many differences. At a first view, there are obviously differences in the addresses between IPv4 and IPv6. IPv6 addresses range from 0000:0000:0000:0000:0000:0000:0000:0000 to ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff. In addition to this preferred format, IPv6 addresses may be specified in two other shortened formats: Omit leading zeros Specify IPv6 addresses by omitting leading zeros. For example, IPv6 address 1050:0000:0000:0000:0005:0600:300c:326b may be written as 1050:0:0:0:5:600:300c:326b. Double colon Specify IPv6 addresses by using double colons (::) in place of a series of zeros. For example, IPv6 address ff06:0:0:0:0:0:0:c3 may be written as ff06::c3. Double colons may be used only once in an IP address. The IPv6 addresses are similar to IPv4 except that they are 16 octets long. A critical fact to be observed is that the present 32-bit IP addresses may be accommodated in IPv6 as a special case of IPv6 addressing. The standard representation of IPv6 addresses is a hexadecimal value of 16-bit each separated by a colon. Not only does IPv6 have different address representation, but it also discards the previous concept of network classes. The 6-byte addresses are very popular in the 802 LANs. The next generation of LANs will use 8-byte address space specified by the Institute of Electrical and Electronics Engineers (IEEE) [9]. Thus, the IPv6 addresses should be 8 bytes long. 2.5.1 IPv6Header Some of  IPv4 header fields excluded in IPv6, and some of  them has been made optional. As a result of this the packet processing time and packet header size is reduced. The header consists of two parts, which are: the basic IPng header and IPng extension headers. 2.5.2.1 Version This field (4-bit long), same as in IPv4 case, is used to determine the version of IP datagram and is set to 6 in the present case. This field is the same in both versions. The reasoning for this is that these two protocols should coexist during the transition period. 2.5.2.2 Flow Label This field is 20 bits long and, as yet, there is no specific functionality assigned to it. 2.5.2.3 Payload Length Only IPv6 has this field. Since the header length is constant in IPv6, just one field is needed. This field replaces IHL and Total Length fields in IPv4. It carries information about the length of data (the headers are not included). 2.5.2.4 Next Header Next Header field replaces the Protocol field in the IPv4 header. 2.5.2.5 Hops limit This field is a hop count that decrements. This field redefines the Time to Life field present in IPv4. 2.5.2.6 Source Address The source address is indicated by this field (16 octets long). No attacks related to this field have been experienced. 2.5.2.7 Destination Address This field (16 octets long) specifies the destination address. No attacks related to this field are known. IPv6 brings major changes to the IP header. IPv6s header is far more flexible and contains fewer fields, with the number of fields dropping from 13 to 8. Fewer header fields result in a cleaner header format and Quality of Service (QoS) that was not present in IPv4. IP option fields in headers have been replaced by a set of optional extensions. The efficiency of IPv6s header can be seen by comparing the address to header size. Even though the IPv6 address is four times as large as the IPv4 address, the header is only twice as large. Priority traffic, such as real time audio or video, can be distinguished from lower priority traffic through a priority field [8]. Based on the [27] experiment, it clearly show the brake-down of the various headers in both IPv4 and IPv6, it is evident that the overhead incurred is minimal between IPv4 and IPv6. In theory, the performance overhead between these two protocols is so minimal that the benefits of IPv6 should quickly overshadow the negatives. Table 1: Packet breakdown and overhead incurred by header information 2.6 Streaming Overview In recent years, there has been major increasing in multimedia streaming application such as audio and video broadcast over internet. The increasing number of internet subscribers with broadband access from both work and home enables multimedia applications with high quality can be delivered to the user. However, since the best effort internet is unreliable with a high packet lost and inconsistency in packet arrival, it does not provide any QoS control. This is a crucial part when dealing with real-time multimedia traffic. The multimedia streaming is a real-time application includes audio and video which is stored in stream server and streamed its content to client upon request. The example includes continuous media server, digital library, and shopping and entertainment services. Prior to streaming, video was usually downloaded. Since, it took a long time to download video files, streaming was invented with the intention of avoiding download delays and enhancing user experience. In streaming, video content is played as it arrives over the network, in the sense that there is no wait period for a complete download. Real-time streaming has a timing constraint such that the data are played continuously. If the packet data are not arrive in time, the playback is paused and will cause the in smoothness in multimedia presentation and its definitely annoying to the user. Because of this factor, multimedia streaming require isochronous processing and QoS [10] from end to end view. The lack of QoS has not prevented the rapid growth of real-time streaming application and this growth is expected to continue and multimedia traffic will form a higher portion of of the internet load. Thus, the overall behavior of these applications will have a significant impact on the other internet traffic. 2.7 Downloading Versus Streaming Application Basically downloading applications such as FTP involve downloading a file before it is viewed by a user. The examples of multimedia downloading applications are downloading an MP3 song to an IPod or any portable device, downloading a video file to a computer via P2P application such as BitTorrent. Downloading is usually a simple and easiest way to deliver media to a user. However, downloading has two potentially important disadvantages for multimedia applications. First, a large buffer is required whenever a large media file such as MPEG-4 movie is downloaded. Second, the amount of time required for the download can be relatively large, (depends on the network traffic), thereby requiring the user to wait minutes or even hours before being able to view the content. Thus, while downloading is simple and robust, it provides only limited flexibility both to users and to application designers. In contrast, in the streaming mode actually is by split the media bit stream into separate packet which can be transmitted independently. This enables the receiver to decode and play back the parts of the bit stream that are already received. The transmitter continues to send multimedia data packet while the receiver decodes and simultaneously plays back other, already received parts of the bit stream. This enables low delay between the current data is sent by the transmitter to the moment it is viewed by the user. Low delay is of paramount importance for interactive applications such as video conferencing, but it is also important both for video on demand, where the user may desire to change channels or programs quickly, and for live broadcast, but the delay must be finite. Another advantage of streaming is its relatively low storage requirements and increased flexibility for the user, compared to downloading. However, streaming applications, unlike downloading applications, have de adlines and other timing requirements to ensure continuous real-time media play out. This leads to new challenges for designing communication systems to best support multimedia streaming applications. [12] 2.8 Standard/Protocols for Streaming A good streaming protocol is required to achieve a quality of continuous playback in multimedia streaming over the internet with the short delay when a user downloading a multimedia content over the internet. The streaming protocol provides a service such as transport, and QoS control mechanism including quality adaptation, congestion control and error control. The streaming protocol is built on the top of network level protocol and the transport level protocol. The multimedia streaming protocol is based on IP network and â€Å"User Datagram Protocol† (UDP) is mainly used, despite of some streaming application using TCP. Like TCP, UDP is a transport layer protocol, but UDP is a connectionless transport protocol. UDP does not guarantee a reliable transmission and in order arrival packet. Under UDP also, there is no guarantee that is packet will arrive to its destination [16]. The UDP packet may get lost in the network when there is a lot of network traffic. Therefore, UDP is not suitable for data packet transfer where a guarantee delivery is important.UDP is never used to send important data such as webpage, database information, etc; UDP is commonly used for streaming audio and video. Streaming media such as Windows Media audio files (.WMA), Real Player (.RM), and others format use UDP because it offers speed. The reason UDP is faster than TCP is because there is no form of flow control or error correction. The data sent over the Inte rnet is affected by collisions, and errors will be present. Remember that UDP is only concerned with speed. This is the main reason why streaming media is not high quality. However, UDP is the ideal transport layer protocol for streaming application which the priority is to transfer the packet from the sender to its destination and does not contribute any delay which is the result of the transmission of lost packets. Since UDP does not guarantee in packet delivery, the client needs to rely Real time Transport Protocol (RTP) [10]. The RTP provides the low-level transport functions suitable for applications transmitting real-time data, such as video or audio, over multicast or unicast services The RTP standard consists of two elementary services, transmitted over two different channels. One of them is the real-time transport protocol which carries the data and the other works as control and monitor channel named RTP control protocol (RTCP) [13]. RTP packets are encapsulated within UDP datagrams. This step incorporates a high throughput and efficient bandwidth usage. The RTP data packets contain a 12 byte header followed by the payload, which can be a video frame, set of audio samples etc. The header includes a payload type indicating the kind of data contained in the packet (e.g. JPEG video, MP3 audio, etc), a timestamp (32 bits), and a sequence number to allow ordering and loss detection of RTP pa ckets [11]. According to the standard [14], the transport of RTP streams can use both UDP and TCP transport protocols, with a strong preference for the datagram oriented support offered by UDP. The primary function of RTCP is to provide feedback on the quality of the data distribution. The feedback may be directly useful for control of adaptive encodings along with fault diagnostics in the transmission. In summary, RTP is a data transfer protocol while RTCP is control protocol. The Real-time Streaming Protocol (RTSP) [25] is a client-server signaling system based on messaging in ASCII format. It establishes procedures and controls, either one or more time-synchronized streams continuous media such as audio and video. The protocol is intentionally similar in syntax and operation to HTTP and therefore hires the option of using proxies, tunnels and caches. RTSP and works well both for large audiences, and single-viewer media-on-demand. RTSP provides control functionality such as pause, fast forward, reverse and absolute positioning and works much like a VCR remote control. The necessary additional information in the negotiation is conducted in the Session Description Protocol (SDP), sent as an attachment of RTSP appropriate response [13]. The Requirement for Multimedia Application Various multimedia applications have different requirements for QoS describes in the following QoS parameters such as throughput, delay, delay variation (jitter) and packet loss. In most cases, the application of QoS requirements can be determine by the user which are the factors that affect the quality of applications [17]. For example, from experimenting concluded that acceptable quality, one-way delay requirements for interactive voice should be less than 250 ms. This delay includes the value of the delays imposed on all components of the communication channels, as a source of delay, transmission delays, delays in the network and the determination of the delay. There are some factors which affect QoS application requirements such as interactive and noninteractive applications, User/Application characteristics (delay tolerance and intolerance, adaptive and nonadaptive characteristics) and application criticality (Mission-critical and non-mission-critical applications) [15]. The thr ee types for this application requirement will be discuss in next section. 2.10.1 Interactive and Noninteractive Applications An interactive application involves some form of between two parties such as people-to-people, people-to-machine or machine-to-machine. An example of interactive applications is: People-to-people application such as IP telephony, interactive voice/video, videoconferencing People-to-machine application such as Video-on-demand (VOD), streaming audio/video Machine-to-machine application: Automatic machine control The time elapsed between interactions is essential to the success of an interactive application. The degree of interactivity determines the level of severity or delay the requirement. For example, interactive voice applications, which involve human interaction (conversation) in real time, are stringent requirements of delay (in order of milliseconds). Streaming (play), video applications involve less interaction and do not require real-time response. Applications streaming, therefore, are more relaxed requirements of delay (in order of seconds). Often applications tolerance delay is determined by users tolerance delay (ie, higher delay tolerance leads to more relaxed delay requirements). Jitter delay is also related to QoS support for interactive tasks. The delay jitter can be corrected by de-jittering techniques buffer. However, the buffer introduces delay in the original signal, which also affects the interactivity of the task. In general, an application with strict requirements de lay also has a strict delay jitter requirements [15]. 2.10.2 Tolerance and Intolerance Tolerance and intolerance also one of the key that affect in QoS parameter values require by the user. Latency tolerance and intolerance determines the strictness of the delay requirement. As we already mentioned, streaming multimedia applications are more latency tolerant than interactive multimedia applications. The level of latency tolerance extremely depends based on users satisfaction, expectation, and the urgency of the application such as mission critical. Distortion tolerance to the commitment of the application quality depends on users satisfaction, users expectation, and the application media types. For example, users are more tolerant to video distortion than to audio distortion. In this case, during congestion, the network has to maintain the quality of the audio output over the quality of the video output [15]. 2.10.3 Adaptive and Nonadaptive Characteristics Adaptive and nonadaptive aspects mostly describe the mechanisms invoked by the applications to adapt to QoS degradation and the common adaptive techniques are rate adaptation and delay adaptation. Rate adaptive application can adjust the data rate injected into the network. During network congestion, the applications reduce the data rate by dropping some packets, increasing the codec data compression, or changing the multimedia properties. This technique may cause degradation of the perceived quality but will keep it within acceptable levels. Delay-tolerant adaptive applications are tolerate to a certain level of delay jitter by deploying the de-jittered buffer or adaptive playback technique. Adaptation is trigged by some form of implicit or explicit feedback from the network or end user [15]. 2.10.4 Application Criticality Mission-critical aspects reflect the importance of application usage, which determines the strictness of the QoS requirements and Failing the mission may result in disastrous consequences. For example: Air Traffic Control Towers (ATCTs): The Traffic controller is responsible to guide the pilot for direction, takeoff and landing process. Life and death of the pilot and passenger may depend on the promptness and accuracy of the Air Traffic Control (ATC) system. E Banking system: The failure of this system may lead to the losses to the bank and user is unable to make an online transaction (view account summary, account history, transaction status, manage cheques and transfer funds online) and to make a online payment ( loans, bills, and credit card) and other transaction. 2.10.6 Examples of Application Requirements Video applications can be classified into two groups: interactive video (i.e., video conferencing, long-distance learning, remote surgery) and streaming video (i.e., RealVideo, Microsoft ASF, QuickTime, Video on Demand, HDTV). As shown in table 2, video applications bandwidth requirements are relatively high depending on the video codec. Video codec Bandwidth Requirement Uncompressed HDTV 1.5 Gbps HDTV 360 Mbps Standard definition TV (SDTV) 270Mbps Compressed MPEG2 25-60 Mbps Broadcast quality HDTV 19.4 Mbps MPEG 2 SDTV 6 Mbps MPEG 1 1.5 Mbps MPEG 4 5 kbps 4 Mbps H.323 (h.263) 28 kbps 1 Mbps Table 2 : Video Codec Bandwidth Requirement [15] 2.11 Packet Delay Delay has a direct impact on users satisfaction. Real-time media applications require the delivery of information from the source to the destination within a certain period of time. Long delays may cause incidents such as data missing the playback point, which can degrade the quality of service of the application. Moreover, it can cause user frustration during interactive tasks. For example, the International Telecommunication Union (ITU) considers network delay for voice applications in Recommendation G.114 and defines three bands of one-way delay as shown in table 2. Range in Millisecond (ms) Description 0 150 Acceptable for most user application. 150 400 Acceptable provided that administrators are aware of the transmission time and the impact it has on the transmission quality of user applications. > 400 Unacceptable for general. However in certain cases this limit exceeds. Table 3: Standard for delay limit for voice In the data transmission process, each packet is moving from its source to its destination. The process of data transmission usually starts with a packet from a ho Internet Protocol Version 4 Analysis Internet Protocol Version 4 Analysis Chapter 2: Literature Review 2.1 Introduction Multimedia streaming over internet is getting its revolutionary in the communication, entertainment and interactive game industries. The web now becomes a popular medium for video streaming since the user does not have to wait to download a large file before seeing the video or hearing the sound. Instead, the media is sent in a continuous stream and is played as it arrives. It can integrate all other media formats such as text, video, audio, images and even live radio and TV broadcasts can all be integrated and delivered through a single medium. These applications may require in terms of bandwidth, latency and reliability than traditional data applications to support the growth of multimedia technology in the future [1]. The transportation of multimedia traffic over networks become more complicated because multimedia is becoming cheaper and cheaper and therefore used more and more. Problems with bearing multimedia flows on networks are mainly related to the bandwidth they require and to the strict maximum delay requirements that must be met [2]. This is important when multimedia applications have to provide users with real-time interaction. Because of the rapid growth of Internet usage and the requirement of different applications, the IPv4 is no more relevant to support the future networks. Many new devices, such as mobile phones, require an IP address to connect to the Internet. Thus, there is a need for a new protocol that would provide new services. To overcome to these problems, a new version of Internet Protocol has been introduced. This is called Internet Protocol next generation (IPng or IPv6), which is designed by the IETF [3] to replace the current version Internet Protocol, IP Version 4 (IPv4). IPv6 is designed to solve the problems of IPv4. It does so by creating a new version of the protocol which serves the function of IPv4, but without the same limitations of IPv4. IPv6 is not totally different from IPv4. The differences between IPv6 and IPv4 are including in five major areas which is addressing, routing, security, configuration and support for mobile devices [4]. Like all the development and new inventio ns, the problems of current Internet Protocol made researcher to develop some new techniques to solve these problems. Even they have tried to make some changes on the current protocol, these changes still didnt help a much. So, at the end the way came to development of a new protocol which is known as IPv6 or IPng. 2.2 OSI 7 Layer Computer networks are complex dynamic systems and difficult task to understand, design, and implement a computer network. Networking protocols need to be established for low level computer communication up to how application programs communicate. Each step in this protocol is called a layer and divided into several layers simplifies the solution. The main idea behind layering is that each layer is responsible for different tasks. The Open System Interconnection (OSI) Reference Model defines seven layers [5]. Physical Layer. This layer deals, for instance, with conversion of bits to electrical signals, bit level synchronization. Data Link Layer. It is responsible for transmitting information across a link, detecting data corruption, and addressing. Network Layer. The layer enables any party in the network to communicate with each other. Transport Layer. It establishes reliable communication between a pair in the system, deals with lost and duplicated packets. Session Layer. This layer is responsible for dialogue control and changing. Presentation Layer. The main task of this layer is to represent data in a way convenient for the user. Application Layer. Applications in this case include Web browsing, file transferring, etc. The Network Layer is the layer that is the most interesting in the context of this project. The following section gives a better view of this layer. 2.3 Network Layer As was mentioned before, this layer is responsible for enabling the communication between any party. The most used method for transporting data within and between communications networks is the Internet Protocol (IP). 2.3.1 Internet Protocol IP is a protocol that provides a connectionless, unreliable, and best-efforts packet delivery system. More details on these network service types are given below [5]. In a connectionless model the data packets are transferred independently from all others and containing full source and the destination address. It is worth mentioning that another type is the connection oriented model. However, the connection-oriented model and its details are beyond the scope of this project and thus will not be pursued in this report. The reader can consult [5] for further information on this type of service. Unreliable delivery means that packets may be lost, delayed, duplicated, delivered non-consecutively (in an order other than that in which they were sent), or damaged in transmission. 2.4 Internet Protocol Version 4 As we know, IPv4 is the current protocol for communication on the Internet. It is the protocol that underlies most communication on networks today, such as TCP/IP and UDP/IP. The largest weakness of IPv4 is its address space [7]. Each IPv4 address only have 32 bits and consists of two parts, defined as network identifier and host identifier [5]. A standard method of displaying an IPv4 address is as decimal value of four octets, each separated a period, for example: 192.168.2.5. Traditionally [6], IP addresses are presented by classfull addressing. 5 classes of address were created, which is A to E. Class A consists of 16,777,214 hosts while class B consists of 65,534 hosts and class C consists of 254 hosts. Class D is reserved for use with multicasting and class E is a block of IP addresses reserved for future use [7]. The class D and E addresses are not used to address public host, so this leaves the rest of the entire range of IP addresses carved up into classes A C. As soon as a site is connected to the Internet, it needs to be given an entire class C. Assuming that many sites only need one or two addresses then this waste over 200 addresses. Once a site reaches over 254 full addressable machines it would need an entire class B, which would waste over 65,000 addresses and so on. This allocation system is obviously insufficient and wastes much of a limited resource. 2.4.1 Header Header is a part of the IP packet[5]. There is a number of fields in an IPv4 header. Below are the some explanations for each field. 2.4.2.1 Version This field (4-bit long) is used to determine the version of IP datagram that is considered. For IPv4 it is set to 4. 2.4.2.12 Internet Header Length (IHL) The Internet Header Length is the length of the header. 2.4.2.3 Type of Service Theoretically, this field (1 octet long) should indicate something special about the protocol. However, it has never really been used. 2.4.2.4 Total Length Total is the length of data in the fragment plus the header. 2.4.2.5 Identification This field is useful for fragmentation only. Its purpose is to enable the destination node to perform reassembly. This implies that the destination node must know which fragments belong to each other, i.e. the source, destination, and protocol fields should match. 2.4.2.6 Offset Offset indicates the point at which this fragment belongs in the reassembly packet. The field is related to fragmentation mechanism and has similar vulnerabilities as the identification field. 2.4.2.7 Time to Live TTL measures the time duration of the datagram presence in a network. This guarantees that no datagram exists forever in the network. 2.4.2.8 Protocol This field identifies the transport protocols, for example UDP or TCP. Since the field contains an arbitrary value that indicates some protocol, encapsulation of one datagram into another (IP tunneling) is possible. 2.4.2.9 Header Checksum The checksum is used to detect transmission errors. However, this field was removed in IPv6. 2.4.2.10 Source Address. This field specifies the source address. 2.4.2.11 Destination Address The destination address (4 octets long) is specified in this field. No attacks related to this field are known. 2.4.2.12 Options The field (variable size) was designed to improve the IP communication. There are several options defined for this field. Among them are: security, source routing, and route recording. 2.4.2.13 Padding The field (variable size) is used to fill the IP header with zeros if the header length is less than 32 bits. 2.5 Internet Protocol Version 6 IPv6 is a new version that is specified in RFC2460 [5] to overcome the weakness of the current protocol in certain aspect. It uses a 128 bit long address field which is 4 times longer than Ipv4 addresses. This size of address space removes one of the worst issues with IPv4 and IPv6 doesnt have classes of addresses. In general, IPv4 and IPv6 have a similar in their basic framework and also many differences. At a first view, there are obviously differences in the addresses between IPv4 and IPv6. IPv6 addresses range from 0000:0000:0000:0000:0000:0000:0000:0000 to ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff. In addition to this preferred format, IPv6 addresses may be specified in two other shortened formats: Omit leading zeros Specify IPv6 addresses by omitting leading zeros. For example, IPv6 address 1050:0000:0000:0000:0005:0600:300c:326b may be written as 1050:0:0:0:5:600:300c:326b. Double colon Specify IPv6 addresses by using double colons (::) in place of a series of zeros. For example, IPv6 address ff06:0:0:0:0:0:0:c3 may be written as ff06::c3. Double colons may be used only once in an IP address. The IPv6 addresses are similar to IPv4 except that they are 16 octets long. A critical fact to be observed is that the present 32-bit IP addresses may be accommodated in IPv6 as a special case of IPv6 addressing. The standard representation of IPv6 addresses is a hexadecimal value of 16-bit each separated by a colon. Not only does IPv6 have different address representation, but it also discards the previous concept of network classes. The 6-byte addresses are very popular in the 802 LANs. The next generation of LANs will use 8-byte address space specified by the Institute of Electrical and Electronics Engineers (IEEE) [9]. Thus, the IPv6 addresses should be 8 bytes long. 2.5.1 IPv6Header Some of  IPv4 header fields excluded in IPv6, and some of  them has been made optional. As a result of this the packet processing time and packet header size is reduced. The header consists of two parts, which are: the basic IPng header and IPng extension headers. 2.5.2.1 Version This field (4-bit long), same as in IPv4 case, is used to determine the version of IP datagram and is set to 6 in the present case. This field is the same in both versions. The reasoning for this is that these two protocols should coexist during the transition period. 2.5.2.2 Flow Label This field is 20 bits long and, as yet, there is no specific functionality assigned to it. 2.5.2.3 Payload Length Only IPv6 has this field. Since the header length is constant in IPv6, just one field is needed. This field replaces IHL and Total Length fields in IPv4. It carries information about the length of data (the headers are not included). 2.5.2.4 Next Header Next Header field replaces the Protocol field in the IPv4 header. 2.5.2.5 Hops limit This field is a hop count that decrements. This field redefines the Time to Life field present in IPv4. 2.5.2.6 Source Address The source address is indicated by this field (16 octets long). No attacks related to this field have been experienced. 2.5.2.7 Destination Address This field (16 octets long) specifies the destination address. No attacks related to this field are known. IPv6 brings major changes to the IP header. IPv6s header is far more flexible and contains fewer fields, with the number of fields dropping from 13 to 8. Fewer header fields result in a cleaner header format and Quality of Service (QoS) that was not present in IPv4. IP option fields in headers have been replaced by a set of optional extensions. The efficiency of IPv6s header can be seen by comparing the address to header size. Even though the IPv6 address is four times as large as the IPv4 address, the header is only twice as large. Priority traffic, such as real time audio or video, can be distinguished from lower priority traffic through a priority field [8]. Based on the [27] experiment, it clearly show the brake-down of the various headers in both IPv4 and IPv6, it is evident that the overhead incurred is minimal between IPv4 and IPv6. In theory, the performance overhead between these two protocols is so minimal that the benefits of IPv6 should quickly overshadow the negatives. Table 1: Packet breakdown and overhead incurred by header information 2.6 Streaming Overview In recent years, there has been major increasing in multimedia streaming application such as audio and video broadcast over internet. The increasing number of internet subscribers with broadband access from both work and home enables multimedia applications with high quality can be delivered to the user. However, since the best effort internet is unreliable with a high packet lost and inconsistency in packet arrival, it does not provide any QoS control. This is a crucial part when dealing with real-time multimedia traffic. The multimedia streaming is a real-time application includes audio and video which is stored in stream server and streamed its content to client upon request. The example includes continuous media server, digital library, and shopping and entertainment services. Prior to streaming, video was usually downloaded. Since, it took a long time to download video files, streaming was invented with the intention of avoiding download delays and enhancing user experience. In streaming, video content is played as it arrives over the network, in the sense that there is no wait period for a complete download. Real-time streaming has a timing constraint such that the data are played continuously. If the packet data are not arrive in time, the playback is paused and will cause the in smoothness in multimedia presentation and its definitely annoying to the user. Because of this factor, multimedia streaming require isochronous processing and QoS [10] from end to end view. The lack of QoS has not prevented the rapid growth of real-time streaming application and this growth is expected to continue and multimedia traffic will form a higher portion of of the internet load. Thus, the overall behavior of these applications will have a significant impact on the other internet traffic. 2.7 Downloading Versus Streaming Application Basically downloading applications such as FTP involve downloading a file before it is viewed by a user. The examples of multimedia downloading applications are downloading an MP3 song to an IPod or any portable device, downloading a video file to a computer via P2P application such as BitTorrent. Downloading is usually a simple and easiest way to deliver media to a user. However, downloading has two potentially important disadvantages for multimedia applications. First, a large buffer is required whenever a large media file such as MPEG-4 movie is downloaded. Second, the amount of time required for the download can be relatively large, (depends on the network traffic), thereby requiring the user to wait minutes or even hours before being able to view the content. Thus, while downloading is simple and robust, it provides only limited flexibility both to users and to application designers. In contrast, in the streaming mode actually is by split the media bit stream into separate packet which can be transmitted independently. This enables the receiver to decode and play back the parts of the bit stream that are already received. The transmitter continues to send multimedia data packet while the receiver decodes and simultaneously plays back other, already received parts of the bit stream. This enables low delay between the current data is sent by the transmitter to the moment it is viewed by the user. Low delay is of paramount importance for interactive applications such as video conferencing, but it is also important both for video on demand, where the user may desire to change channels or programs quickly, and for live broadcast, but the delay must be finite. Another advantage of streaming is its relatively low storage requirements and increased flexibility for the user, compared to downloading. However, streaming applications, unlike downloading applications, have de adlines and other timing requirements to ensure continuous real-time media play out. This leads to new challenges for designing communication systems to best support multimedia streaming applications. [12] 2.8 Standard/Protocols for Streaming A good streaming protocol is required to achieve a quality of continuous playback in multimedia streaming over the internet with the short delay when a user downloading a multimedia content over the internet. The streaming protocol provides a service such as transport, and QoS control mechanism including quality adaptation, congestion control and error control. The streaming protocol is built on the top of network level protocol and the transport level protocol. The multimedia streaming protocol is based on IP network and â€Å"User Datagram Protocol† (UDP) is mainly used, despite of some streaming application using TCP. Like TCP, UDP is a transport layer protocol, but UDP is a connectionless transport protocol. UDP does not guarantee a reliable transmission and in order arrival packet. Under UDP also, there is no guarantee that is packet will arrive to its destination [16]. The UDP packet may get lost in the network when there is a lot of network traffic. Therefore, UDP is not suitable for data packet transfer where a guarantee delivery is important.UDP is never used to send important data such as webpage, database information, etc; UDP is commonly used for streaming audio and video. Streaming media such as Windows Media audio files (.WMA), Real Player (.RM), and others format use UDP because it offers speed. The reason UDP is faster than TCP is because there is no form of flow control or error correction. The data sent over the Inte rnet is affected by collisions, and errors will be present. Remember that UDP is only concerned with speed. This is the main reason why streaming media is not high quality. However, UDP is the ideal transport layer protocol for streaming application which the priority is to transfer the packet from the sender to its destination and does not contribute any delay which is the result of the transmission of lost packets. Since UDP does not guarantee in packet delivery, the client needs to rely Real time Transport Protocol (RTP) [10]. The RTP provides the low-level transport functions suitable for applications transmitting real-time data, such as video or audio, over multicast or unicast services The RTP standard consists of two elementary services, transmitted over two different channels. One of them is the real-time transport protocol which carries the data and the other works as control and monitor channel named RTP control protocol (RTCP) [13]. RTP packets are encapsulated within UDP datagrams. This step incorporates a high throughput and efficient bandwidth usage. The RTP data packets contain a 12 byte header followed by the payload, which can be a video frame, set of audio samples etc. The header includes a payload type indicating the kind of data contained in the packet (e.g. JPEG video, MP3 audio, etc), a timestamp (32 bits), and a sequence number to allow ordering and loss detection of RTP pa ckets [11]. According to the standard [14], the transport of RTP streams can use both UDP and TCP transport protocols, with a strong preference for the datagram oriented support offered by UDP. The primary function of RTCP is to provide feedback on the quality of the data distribution. The feedback may be directly useful for control of adaptive encodings along with fault diagnostics in the transmission. In summary, RTP is a data transfer protocol while RTCP is control protocol. The Real-time Streaming Protocol (RTSP) [25] is a client-server signaling system based on messaging in ASCII format. It establishes procedures and controls, either one or more time-synchronized streams continuous media such as audio and video. The protocol is intentionally similar in syntax and operation to HTTP and therefore hires the option of using proxies, tunnels and caches. RTSP and works well both for large audiences, and single-viewer media-on-demand. RTSP provides control functionality such as pause, fast forward, reverse and absolute positioning and works much like a VCR remote control. The necessary additional information in the negotiation is conducted in the Session Description Protocol (SDP), sent as an attachment of RTSP appropriate response [13]. The Requirement for Multimedia Application Various multimedia applications have different requirements for QoS describes in the following QoS parameters such as throughput, delay, delay variation (jitter) and packet loss. In most cases, the application of QoS requirements can be determine by the user which are the factors that affect the quality of applications [17]. For example, from experimenting concluded that acceptable quality, one-way delay requirements for interactive voice should be less than 250 ms. This delay includes the value of the delays imposed on all components of the communication channels, as a source of delay, transmission delays, delays in the network and the determination of the delay. There are some factors which affect QoS application requirements such as interactive and noninteractive applications, User/Application characteristics (delay tolerance and intolerance, adaptive and nonadaptive characteristics) and application criticality (Mission-critical and non-mission-critical applications) [15]. The thr ee types for this application requirement will be discuss in next section. 2.10.1 Interactive and Noninteractive Applications An interactive application involves some form of between two parties such as people-to-people, people-to-machine or machine-to-machine. An example of interactive applications is: People-to-people application such as IP telephony, interactive voice/video, videoconferencing People-to-machine application such as Video-on-demand (VOD), streaming audio/video Machine-to-machine application: Automatic machine control The time elapsed between interactions is essential to the success of an interactive application. The degree of interactivity determines the level of severity or delay the requirement. For example, interactive voice applications, which involve human interaction (conversation) in real time, are stringent requirements of delay (in order of milliseconds). Streaming (play), video applications involve less interaction and do not require real-time response. Applications streaming, therefore, are more relaxed requirements of delay (in order of seconds). Often applications tolerance delay is determined by users tolerance delay (ie, higher delay tolerance leads to more relaxed delay requirements). Jitter delay is also related to QoS support for interactive tasks. The delay jitter can be corrected by de-jittering techniques buffer. However, the buffer introduces delay in the original signal, which also affects the interactivity of the task. In general, an application with strict requirements de lay also has a strict delay jitter requirements [15]. 2.10.2 Tolerance and Intolerance Tolerance and intolerance also one of the key that affect in QoS parameter values require by the user. Latency tolerance and intolerance determines the strictness of the delay requirement. As we already mentioned, streaming multimedia applications are more latency tolerant than interactive multimedia applications. The level of latency tolerance extremely depends based on users satisfaction, expectation, and the urgency of the application such as mission critical. Distortion tolerance to the commitment of the application quality depends on users satisfaction, users expectation, and the application media types. For example, users are more tolerant to video distortion than to audio distortion. In this case, during congestion, the network has to maintain the quality of the audio output over the quality of the video output [15]. 2.10.3 Adaptive and Nonadaptive Characteristics Adaptive and nonadaptive aspects mostly describe the mechanisms invoked by the applications to adapt to QoS degradation and the common adaptive techniques are rate adaptation and delay adaptation. Rate adaptive application can adjust the data rate injected into the network. During network congestion, the applications reduce the data rate by dropping some packets, increasing the codec data compression, or changing the multimedia properties. This technique may cause degradation of the perceived quality but will keep it within acceptable levels. Delay-tolerant adaptive applications are tolerate to a certain level of delay jitter by deploying the de-jittered buffer or adaptive playback technique. Adaptation is trigged by some form of implicit or explicit feedback from the network or end user [15]. 2.10.4 Application Criticality Mission-critical aspects reflect the importance of application usage, which determines the strictness of the QoS requirements and Failing the mission may result in disastrous consequences. For example: Air Traffic Control Towers (ATCTs): The Traffic controller is responsible to guide the pilot for direction, takeoff and landing process. Life and death of the pilot and passenger may depend on the promptness and accuracy of the Air Traffic Control (ATC) system. E Banking system: The failure of this system may lead to the losses to the bank and user is unable to make an online transaction (view account summary, account history, transaction status, manage cheques and transfer funds online) and to make a online payment ( loans, bills, and credit card) and other transaction. 2.10.6 Examples of Application Requirements Video applications can be classified into two groups: interactive video (i.e., video conferencing, long-distance learning, remote surgery) and streaming video (i.e., RealVideo, Microsoft ASF, QuickTime, Video on Demand, HDTV). As shown in table 2, video applications bandwidth requirements are relatively high depending on the video codec. Video codec Bandwidth Requirement Uncompressed HDTV 1.5 Gbps HDTV 360 Mbps Standard definition TV (SDTV) 270Mbps Compressed MPEG2 25-60 Mbps Broadcast quality HDTV 19.4 Mbps MPEG 2 SDTV 6 Mbps MPEG 1 1.5 Mbps MPEG 4 5 kbps 4 Mbps H.323 (h.263) 28 kbps 1 Mbps Table 2 : Video Codec Bandwidth Requirement [15] 2.11 Packet Delay Delay has a direct impact on users satisfaction. Real-time media applications require the delivery of information from the source to the destination within a certain period of time. Long delays may cause incidents such as data missing the playback point, which can degrade the quality of service of the application. Moreover, it can cause user frustration during interactive tasks. For example, the International Telecommunication Union (ITU) considers network delay for voice applications in Recommendation G.114 and defines three bands of one-way delay as shown in table 2. Range in Millisecond (ms) Description 0 150 Acceptable for most user application. 150 400 Acceptable provided that administrators are aware of the transmission time and the impact it has on the transmission quality of user applications. > 400 Unacceptable for general. However in certain cases this limit exceeds. Table 3: Standard for delay limit for voice In the data transmission process, each packet is moving from its source to its destination. The process of data transmission usually starts with a packet from a ho