Denial of service issues and solutions Dissertation

Denial of service issues and solutions - Dissertation Example (Chau) The real intent of those attacks is to shut down a site and not to penetrate it. Purpose may also be vandalism, extortion or social action including terrorism. (Crocker, 2007) 1.3 How DoS works The nature of DoS can be explained using Figure 1.1. In the figure, Bob is the authentic user of the system and he sends messages using the insecure Internet to the server. Darth, the attacker interfere the services offered by server and make the genuine user, Bob, invisible to server. In a normal connection, users transmit a message to the server to get authentication from the server. Then, the server returns a message to authenticate to the user as a genuine user of the system. Also, from the user side, the acknowledge message is sent back to approve the server and the connection between the user and the server is established. Figure 1.1 Denial of Service (Stallings, 2006) When a denial of service attack is taken place, the server receives several authentication requests, seemingly ca me from the authentic users, which have false return addresses. The server fails to successfully locate the user while trying to return the authentication acknowledgement. Then, the server waits so that it can authenticate the user before stopping the connection. In most DoS attacks, the attackers flood the servers with forged requests and make servers delayed. 1.4 Types and Generation of DoS Attacks Generally, there are three major classifications of DoS attacks depending on the victims targeted by attackers—users, hosts or networks though there are several types of DoS attack prevalent on Internet. US Cert advisory suggests that the three main types of DoS attacks are bandwidth, protocol and software vulnerability attacks. The major aspects that most DoS attacks are focusing on are bandwidth, CPU time and memory. Most common DoS attacks can be summarized as the following. 1.4.1 TCP SYN Flood Attack Flood type attacks are the first known form of a DoS attack and their attack ing mechanism of is quite simple – attackers send more traffic to a server than it can handle. (Georgieva, 2009) SYN Flood attack is a protocol type and exploits the weakness of TCP/IP protocol. US CERT advisory defines SYN flood as â€Å"an asymmetric resource starvation attack in which the attacker floods the victim with TCP SYN packets and the victim allocates resources to accept perceived incoming connections†. In TCP SYN flood attack, the legitimate users are ignored when the attacker initiates a TCP connection to the serve with a SYN. The victim server responds to the request with spoofed IP address and waits for ACK from the client side. Then, the connection table of the server is filled up and it neglects all new connections from legitimate users. This phenomenon can be clarified using Figure 1.2. Figure 1.2 Comparison of Normal TCP 3 ways Handshake and TCP SYN Flood attack demonstration (cisco.com) Flood type attacks are so common and powerful. Georgieva (2009 ) suggests that â€Å"even if a webmaster adds more bandwidth, this still is not a sufficient protection against a flood attack†. Because of the bandwidth insufficiency, even the normal volume of legitimate requests may appear as flood attacks. 1.4.2 Ping of Death Attack The Ping of Death or POD attack is another DoS attack with simple principle. It exploits software vulnerab

Exploratory Literature Research Paper Essay Example | Topics and Well Written Essays - 3250 words

Exploratory Literature Research Paper - Essay Example pirical research about the "best" type of leadership we find support for every leadership style from â€Å"the transformational leader†, who encourages followers to ignore their self-interests for the good of the organization, to â€Å"the authoritative leader†, who runs a paternalistic organization, but treats employees with respect. The data also supports the fact that the most effective leadership is one which relies on a variety of tools from transformational to authoritative. The topic that has been chosen by the researcher for the purpose of this study is the comparison of the various management styles impact on employee efficiency. The researcher expects that the study will be greatly useful for the research world as well as the industry. The author expects that the insights from this research will enable industry to understand the impact of the various management styles on employee satisfaction, motivation and efficiency. The findings from the research will enable the industry to find the most appropriate management style. The area of management style has been quite popular amongst researchers. The exploratory research will enable the researcher to present a complete picture of the existing research in the field of management styles. The study will prove to be useful as a basis for future research in the same field. The research method that shall be chosen by the researcher in order to arrive at conclusive answers to the three questions shall be such that it shall give the researcher enough evidence to come to a conclusion. For the first question, the researcher proposes to analyze already available literature in the field to find out what are the various management styles that have already been researched. This method which is called literature review will give a clear picture of the characteristics of various management styles that are into existence. For answering the second question, the author will attempt to find out articles that present

Biochip technology Essay Example for Free

Biochip technology Essay The term global village is one popularized by Canadian communications theorist Marshall McLuhan to refer to the ability of electronic communications technologies to collapse notions of geography and disrupt the conventional wisdom by which society appraises time-space relations. At the heart of the concept of the global village is the idea that because electronic communications technology are exponentially increasing their ability to abnegate space and time limitations, they enable individuals, societies and institutions to operate on a larger scale than before – phone calls can be made across greater distances at reduced costs, e-mails allow instantaneous transmission of readable content and cellular technology increases the mobility of telephony. Whereas the domain we used to operate on was on the village-scale, it is now global: a global village. McLuhan effectively celebrated the development of the global village because he believed that it would expand our social consciousness. Not necessarily make us more socially conscious, but at the very least increase the scale by which we already think. Where we used to think primarily in terms of local affairs and developments that are mostly proximate to our surroundings, the ability to transmit developments instantaneously means that citizens can now think on an enlarged scale. More enthusiastic neo-McLuhanists maintain that the global village will eradicate all barriers to cultures, nations and political institutions. However, there is some concern that this is not entirely a good thing. For example, some have worried that expanding the individual consciousness to meet the scale of the global village comes at a cost. In effect, by thinking on the global scale, individuals may find themselves effectively disengaged from local concerns and proximate issues and at the very worse actively following developments in communities they have no power to affect, and disengaged from local developments that they could realistically make a difference in. Castells (1997) contends, however, that the globalizing effects of Internet and other similar networking technologies will not necessarily eradicate political boundaries. Rather the side effect of the Information Age is that many of the things that have come to define the nation state will be effectively downsized. Sovereignty will no longer figure in the absolute sense that we have understood it before, but rather, nation-states will exist solely due to the network of alliances, commitments, responsibilities and subordinations that are more than just existent for the benefit of the state, but are necessary to its existence, and this becomes possible due to the ability to instantiate relationships through networking technologies. It is this component of Castell’s understanding of globalizing effects which hold some consonance with the views of Ulrich Beck. Beck maintains that much of the failure to really take measure of the effects of globalization is derived from a limited understanding of it. Beck contends that globalization is not something that is limited to economic relationships and complex trade relations, but something that occurs in the most internalized sense, such as the ways by which we navigate culture and social relationships in an expanded transnational view that is the result of a national sense sublimated by globalizing technologies, cultural exchanges and international relationships. However, because of the co-dependencies brought upon by the transition into Castell’s â€Å"network state,† there is a risk that globalization will erode what sovereignty and democracy there is in the weaker nation-states. In other words, rather than acting as a force for solidarity, globalization could erode democratic controls and constitute a political and economic injustice to the nation-state. This is possible when a nation-state is unable to negotiate for the betterment of its community (whether through incompetence and corruption from the weaker country, or exploitation and deception from the stronger one. ) Globalization cannot end democracy per se, but it risks compromising it to the point of rendering it ineffective. REFERENCES Castells, M 1997, The End of the Millennium, The Information Age: Economy, Society and Culture Vol. 3. Blackwell, Cambridge, Massachussetts. Beck, U 2000, What is Globalization? Polity Press, Cambridge. McLuhan, M 1986, The Global Village, Oxford University Press: New York.

Debate on Free Will Vs Determinism

Debate on Free Will Vs Determinism The debate over free will and determinism has been going on for centuries from the time of great thinkers like Thomas Hobbes and Isaac Newton and therefore these debates have been the part of political and economic theories. Centuries back, majority adopted the notion of determinism and destiny which never allowed individuals to think out of the box. It restricted the individuals then to their resources and their philosophy permitted them to want for more. If it was not for free will then a person born disabled would give up all the hopes in life and would not find cure to make his life better, populations would accept oppression and ignore the fact of a revolution. Along with this, law and justice could not be enforced as the judgements would be made on destiny. Although determination is deeply rooted from centuries asit dictates the life of disabled people like Tatyana McFadden and luck plays its part as it did for Justin Bieber, however free will is the ideology of modern world be cause it has given birth to the concept of accountability, struggle, hard work, courage, planning, and therefore effecting norms of social responsibility and renaissance. Free will is making decisions based on desires and then being accountable for the fact that whether it is a bad or good decision. The theory of free will suggests that the individual makes decisions according to his preferences and is responsible for it, i.e. the individual is rational and is not bounded by any external factors and what he chooses is best for him. Doctor Herald Shipman portrays this theory as he first chose to be a doctor and then later used his profession to be a murderer. After witnessing his mother’s sufferings from lung cancer Shipman motivated himself to be a doctor. After graduating as a doctor in 1970, Shipman changed his priorities and chose to kill his patients. He was sent to a rehab when it was found that he is addicted to a painkiller which he used to obtain from his patient’s prescriptions and suffered constant blackouts due to it. However, after two years he was declared fit and got his license reissued. After getting a second chance Shipm an never changed his priorities and ended up killing 250 of his patients intentionally. When proven guilty, Shipman was jailed where he chose to commit suicide. Hence individuals like Shipman chose what they seek are best for them and are held completely responsible for it. Along with this free will has its cons too and it can lead an individual to ignore all the limits and end up in bad acts. It all depends on the personal responsible that how he treats it. Free will can be devastating for a person as in the case of Malcolm X who indulged in larceny, drugs and prostitution before he found the purpose of his life. Malcolm X had a turbulent early life, his house was burnt down. His father died when Malcolm was six years old and his mother suffered emotional breakdown and was sent to rehab. Malcolm had to live in an orphanage for few years. Later he got to know gangsters, thieves, pimps and drug dealers. He ended up being a drug addict and adopted burglary as means of earning; some biographies even say that sometimes he had sex with other men to earn money. He was arrested for burglary at the age of twenty and was imprisoned for seven years. Malcolm X is a great example of free will in itself however he chose activities which disintegrated his life. Furthermore free will impacts the decision making power of an individual as it governs one’s aptitude to struggle, recognize their abilities and ponder over how to make use of them. It empowers one to motivate them and not give up in life. For example Oprah Winfrey had to face harsh realities very early in her life but she never thought of giving up and ended up being an inspirational figure for women all over the world. Winfrey suffered from sexual harassment in her childhood and all the tensions forced her to run from her house in her teen age. However she chose a better life for herself and with her free will and spirit she made decisions which helped her improving her life. Her willpower can be seen from the fact that after such a disappointing childhood Oprah never gave up and sought way in education; winning scholarship at a university. She recognized her abilities as a motivational speaker and joined a radio station at the age of seventeen and later she hosted The Oprah Winfrey show and became the voice of thousands of people. This reflects that her passion and commitment with her work and will to not give up made her one of the most influential personalities in the world. On the contrary, the concept of predestined has a major part as some characteristics are determined by birth and they structure one’s future, i.e. whether that individual gives up or fight hard against the odds. Tatyana McFadden is a great example of the later as she was born with a paralyzed lower part of body but still ended up being gold medallist in Paralympics. When her mother got to know of her daughter’s disability she abandoned her and McFadden lived in an orphanage for six years. McFadden however was optimistic and had to walk on her hands because she was not able to afford a wheelchair. She never got discouraged by her illness and after her adoption she took part in many sports like gymnastics and wheelchair basketball. At the age of eight she won two medals in Athens and since then McFadden hasn’t looked back and went on going to win sixteen medals, including nine gold medals in her career. Hence it can be implicated that free will is the answer to hur dles set by what is determined at the start of one’s life and how that individual wants to go along the life. Along with this destiny determines success for some and over shadow the free will, the very pattern worked for Justin Bieber as his career began through cyber fame. Destiny determined Justin Bieber to be where he is today, it casted away his free will. Bieber’s career started when he uploaded his music videos on You Tube to show his friends and family. He was lucky when Ushers agency contacted him and signed him up for Hollywood. It’s destiny that can change people’s lives in seconds and can ruin it at the same time. There are so many talented people who upload videos on You Tube but all do not have the luck to be famous. Free will does not only direct the life of an individual but thrives the success of many great nations and teams. From all the success stories of independence, fights, revolutions and renaissance it can be seen that it is the will of the people constituting that notion and uniting themselves to bring success. Manchester United is a living model of such teams who combat what is determined for them. On the sixth of February 1958, United’s squad was returning to The UK when their plane crashed at Munich Airport after it was refuelled and out of forty four passengers, twenty one died instantly and many of the team members died later. Nonetheless, United never gave up and the depleted team went on Semi Finals of the European cup the same year. The staff and players together supported each other and were eager to regain their status as champions. This willingness to succeed and not to give up resulted in United becoming the English Champions nineteen times and the European Champions thrice since then. This verifies that free will can lead to hard work and can overturn the routes laid by what is predestined and of that what is to come in future. Free will and determinism are two concepts which are very much different from each other but also related at the same time. Stephen Hawking, an active member at Cambridge University is quoted as saying â€Å"I have noticed even people who claim everything is predestined, and that we can do nothing to change it, look before they cross the road.† Apart from this, success stories of Winfrey, McFadden and Manchester United reflect how individuals are masters of their own ships and they never let the circumstances, determinism or destiny take over them. These people choose their own destiny and outcomes. It is true that determinism exists but if the concept of free will is eliminated then the models of social responsibility, accountability, law and justice, morality, hard work and planning will all fail and life will have no meaning. Therefore it can be concluded that free will navigates the life of individuals as it allows them to tress pass determinism.

Ultimate Frisbee :: sports

  Ã‚  Ã‚  Ã‚  Ã‚  Before you hear about Ultimate Frisbee, you should first know the history of the Frisbee. The Frisbie Pie Company sold their pies all over the East Coast, and it just happened that the pie tins were easy to throw around. At Yale, students began to make up games to play with the tins, and started to call them â€Å"Frisbees†. The name stuck and tossing the tins around became popular at many East Coast colleges. Several years later, an inventor decided to recreate the Frisbee tin. He wanted to make it out of plastic, which was one of the new post-war materials. He shaped his new disk like a U.F.O., complete with little windows. This was the first real Frisbee, and since then, the design hasn’t changed much. People had been tossing Frisbees around for years, but had yet to create a sport using the Frisbee disk. At Columbia High School in New Jersey, students from the school newspaper created a new sport, combining different aspects of soccer, football, basketball, team handball, and hockey, they called it Ultimate Frisbee. These students decided to write an official set of rules for Ultimate Frisbee. At first, it was only played by a few students at Columbia. The sport soon caught on at other colleges and high schools in the area. From then on, Ultimate spread rapidly throughout the United States, and was at first played only in schools. Since then many non-scholastic leagues have formed and many countries have started national teams. Not much has changed since the rules were first published, and since then, Ultimate has spread all over the world.   Ã‚  Ã‚  Ã‚  Ã‚  The Spirit of the Game is the most important part of Ultimate Frisbee. In most sports, players purposefully foul their opponents. In Ultimate, the philosophy is that no one would ever foul an opposing player on purpose, and if a foul is to occur, it is assumed that the perpetrator fouled by accident. Players call their own fouls, and if the opposing team feels that the call was incorrect, they can contest it. Not having a referee involved means less time wasted. Another part of The Spirit of the Game is showing respect for your teammates and opponents. This â€Å"philosophy† is what makes Ultimate Frisbee different from all other sports.  Ã‚  Ã‚  Ã‚  Ã‚     Ã‚  Ã‚  Ã‚  Ã‚  Once you figure out how to throw the disk, Ultimate’s a pretty easy game to learn. The game starts with both teams lining up on opposite end zones, the home team throws off to the opposing team; that starts the point.

Comparison of poems. Essay -- English Literature

Comparison of poems. In this introduction I am intending to compare and contrast two poems. The poems I am contrasting are called ‘London’ and ‘Composed Upon Westminster’. These two poems are written in the 19th century. The writers had the same ideas about the two poems. The poems are both about London. The writers both give a different view of London. The London poem is written by William Blake in 1757-1827. The Westminster poem written by William Wordsworth in 1770 – 1850 Blake’s representation of London is bleak. The title London is short and gets straight to the point. The first verse is a description of the city, streets, rivers and the people in the city. The first line creates a feeling like London is being owned. It is described like hell. The quote is â€Å"I wonder thro each chattered streets, near were the chartered Thames does flow. Blake has a sinister view of London. He describes it like a prison. The second two lines inverse 1 is about the people. The quote is ‘and marks in every face I meet, marks of weakness marks of woe.’ These two lines mean when Blake sees people on the streets of London they have marks on their faces. The last quote means that the people are weak, have grief and sorrow. The imagery Blake creates in the first verse is of the empty streets and the flowing Thames. The second verse is about the people. â€Å"In every cry of every man† â€Å"in every infants cry of fear† the imagery the second verse suggests pain. â€Å"Infants cry† of mental torture â€Å"mind forged manacles†. There is a lot of repetition. In the second verse Blake emphasises on the word ‘every’ to really put the pain across. The third verse is about the institutions and culture. Blake says ‘the chimney sweepers cry’. ... ...s like heaven. Wordsworth is in a dream. He is describing London as romantic. The similarities both of these poems are that Blake says marks of weakness marks of woe. Wordsworth says mighty heart. Blake says blackening church, hapless soldier, palace walls. Wordsworth says ships, towers, domes, theatres, temples. Blake says chimney sweepers and blackening church. Wordsworth says smokeless air. Blake says chartered Thames does flow and Wordsworth says the river glideth at his own sweet will. Blake says midnight streets and Wordsworth says valleys rocks or hills. Blake says midnight and Wordsworth says bright and glittery. He also says morning. Blake says cry in every man and Wordsworth says calm so deep. The poem that gives me a better description of London is Blake’s point of view. He has a simple structure and his description is very descriptive.

Krogstad’s blackmailing of Nora in regards to Nora’s illegal

Henrik Ibsen's â€Å"A Doll's House† is the story of Nora Helmer and the events that led to her independence.   At the end of the play, Nora decides to leave her husband, Torvald.One central event ultimately led to her decision to leave: Krogstad's blackmailing of Nora in regards to Nora's illegal borrowing of money in order to travel with Torvald to Italy for a cure for his illness.   Nora's predicament led to a major life change.   Nora had to leave at the end of the play because she realized who her husband really was, and what her life actually turned out to be.Nora began her awakening when she started secretly working to pay back the money she borrowed illegally for her and Torvald's trip to Italy to cure Torvald of his illness.   This event led to her fully realizing that her life was not what it should be.   Toward the end of the play, when Nora had made up her mind to leave Torvald, she states, â€Å"I lived by doing tricks for you, Torvald.But that's the wa y you wanted it.   You and Daddy did me a great wrong.   It's your fault that I've never made anything of my life.†Ã‚   (Ibsen 1879/1998, act 3; 80).   From this statement, it is obvious that Nora finally realized the truth about her life.   She acted the part of a child, only living to please first her father, then her husband.Toward the end, however, she realized that those two men compelled her to behave in a certain way, and that this behavior had stunted her growth from child to adult.   She had existed only to please men, therefore making nothing of her life.   She decided to leave Torvald, not to punish him, but to make something of her life; to gain independence from other people.Nora had to leave Torvald because she realized that she did not know him like she thought she did.   When Torvald found out about her illegal dealings, Nora thought he would take the blame for her and risk his own honor.When this did not happen, the image of the good and noble hu sband she though Torvald was had been shattered.   Once this happened, a domino-effect was created; Nora's other illusions about her life, such as her having a happy marriage, were also shattered.   She began to see Torvald for who he really is, and this directly led to her leaving her husband.