Packet-Hiding Method for Preventing Selective Jamming Attack

Packet-Hiding Method for Preventing Selective Jamming Attack Abstract The open nature of the wireless medium leaves it vulnerable to intentional interference attacks, typically referred to as jamming. This intentional interference with wireless transmissions can be used as a launchpad for mounting Denial-of-Service attacks on wireless networks. Typically, jamming has been addressed under an external threat model. However, adversaries with internal knowledge of protocol specifications and network secrets can launch low-effort jamming attacks that are difficult to detect and counter. In this work, we address the problem of selective jamming attacks in wireless networks. In these attacks, the adversary is active only for a short period of time, selectively targeting messages of high importance. We illustrate the advantages of selective jamming in terms of network performance degradation and adversary effort by presenting two case studies; a selective attack on TCP and one on routing.We show that selective jamming attacks can be launched by performing real -time packet classification at the physical layer. To mitigate these attacks, we develop three schemes that prevent real-time packet classification by combining cryptographic primitives with physical-layer attributes. We analyze the security of our methods and evaluate their computational and communication overhead. Algorithm 1. Symmetric encryption algorithm 2. Brute force attacks against block encryption algorithms Algorithm Description We propose a solution based on All-Or- Nothing Transformations (AONT) that introduces a modest communication and computation overhead. Such transformations were originally proposed by Rivest to slow down brute force attacks against block encryption algorithms . An AONT serves as a publicly known and completely invertible pre-processing step to a plaintext before it is passed to an ordinary block encryption algorithm. Architecture Existing System Jamming attacks are much harder to counter and more security problems. They have been shown to actualize severe Denial-of-Service (DoS) attacks against wireless networks. In the simplest form of jamming, the adversary interferes with the reception of messages by transmitting a continuous jamming signal , or several short jamming pulses jamming attacks have been considered under an external threat model, in which the jammer is not part of the network. Under this model, jamming strategies include the continuous or random transmission of highpower interference signals Proposed System In this paper, we address the problem of jamming under an internal threat model. We consider a sophisticated adversary who is aware of network secrets and the implementation details of network protocols at any layer in the network stack. The adversary exploits his internal knowledge for launching selective jamming attacks in which specific messages of high importance are targeted. For example, a jammer can target route-request/route-reply messages at the routing layer to prevent route discovery, or target TCP acknowledgments in a TCP session to severely degrade the throughput of an end-to-end flow To launch selective jamming attacks, the adversary must be capable of implementing a classify-then-jam strategy before the completion of a wireless transmission. Such strategy can be actualized either by classifying transmitted packets using protocol semantics, or by decoding packets on the fly. In the latter method, the jammer may decode the first few bits of a packet for recovering useful packet identifiers such as packet type, source and destination address. After classification, the adversary must induce a sufficient number of bit errors so that the packet cannot be recovered at the receiver [34]. Selective jamming requires an intimate knowledge of the physical (PHY) layer, as well as of the specifics of upper layers Modules:- 1. Network module 2. Real Time Packet Classification 3. Selective Jamming Module 4. Strong Hiding Commitment Scheme (SHCS) 5. Cryptographic Puzzle Hiding Scheme (CPHS) Module Descriptions Network module- We address the problem of preventing the jamming node from classifying m in real time, thus mitigating Js ability to perform selective jamming. The network consists of a collection of nodes connected via wireless links. Nodes may communicate directly if they are within communication range, or indirectly via multiple hops. Nodes communicate both in unicast mode and broadcast mode. Communications can be either unencrypted or encrypted. For encrypted broadcast communications, symmetric keys are shared among all intended receivers. These keys are established using preshared pairwise keys or asymmetric cryptography. Real Time Packet Classification Consider the generic communication system depicted in Fig. At the PHY layer, a packet m is encoded, interleaved, and modulated before it is transmitted over the wireless channel. At the receiver, the signal is demodulated, deinterleaved, and decoded, to recover the original packet m. Moreover, even if the encryption key of a hiding scheme were to remain secret, the static portions of a transmitted packet could potentially lead to packet classification. This is because for computationally-efficient encryption methods such as block encryption, the encryption of a prefix plaintext with the same key yields a static ciphertext prefix. Hence, an adversary who is aware of the underlying protocol specifics (structure of the frame) can use the static ciphertext portions of a transmitted packet to classify it. 3. Selective Jamming Module We illustrate the impact of selective jamming attacks on the network performance. implement selective jamming attacks in two multi-hop wireless network scenarios. In the first scenario, the attacker targeted a TCP connection established over a multi-hop wireless route. In the second scenario, the jammer targeted network-layer control messages transmitted during the route establishment process selective jamming would be the encryption of transmitted packets (including headers) with a static key. However, for broadcast communications, this static decryption key must be known to all intended receivers and hence, is susceptible to compromise. An adversary in possession of the decryption key can start decrypting as early as the reception of the first ciphertext block. 4. Strong Hiding Commitment Scheme (SHCS) We propose a strong hiding commitment scheme (SHCS), which is based on symmetric cryptography. Our main motivation is to satisfy the strong hiding property while keeping the computation and communication overhead to a minimum. The computation overhead of SHCS is one symmetric encryption at the sender and one symmetric decryption at the receiver. Because the header information is permuted as a trailer and encrypted, all receivers in the vicinity of a sender must receive the entire packet and decrypt it, before the packet type and destination can be determined. However, in wireless protocols such as 802.11, the complete packet is received at the MAC layer before it is decided if the packet must be discarded or be further processed . If some parts of the MAC header are deemed not to be useful information to the jammer, they can remain unencrypted in the header of the packet, thus avoiding the decryption operation at the receiver. 5. Cryptographic Puzzle Hiding Scheme (CPHS) we present a packet hiding scheme based on cryptographic puzzles. The main idea behind such puzzles is to force the recipient of a puzzle execute a pre-defined set of computations before he is able to extract a secret of interest. The time required for obtaining the solution of a puzzle depends on its hardness and the computational ability of the solver. The advantage of the puzzlebased scheme is that its security does not rely on the PHY layer parameters. However, it has higher computation and communication overhead We consider several puzzle schemes as the basis for CPHS. For each scheme, we analyze the implementation details which impact security and performance. Cryptographic puzzles are primitives originally suggested by Merkle as a method for establishing a secret over an insecure channel. They find a wide range of applications from preventing DoS attacks to providing broadcast authentication and key escrow schemes System Requirements: Hardware Requirements: System: Pentium IV 2.4 GHz. Hard Disk: 40 GB. Floppy Drive: 1.44 Mb. Monitor: 15 VGA Colour. Mouse: Logitech. Ram: 256 Mb. Software Requirements: Operating system :- Windows XP Professional Front End :- JAVA, Swing(JFC),RMI Tool :Eclipse 3.3

Science Education Reform :: essays papers

Science Education Reform The entire purpose of educational reform is to improve the learning of the students. With that in mind, state governments have been and continue to implement programs in their school systems geared towards improving academic performance. Topics under consideration and implementation include lengthening the school day and, in turn, lengthening the school year. This would allow more time for more time for instruction. An important part of educational reform is the reform of teacher education. Nationwide, state school systems are improving the preparation and performance with more meticulous graduation requirements, performance based pay, and â€Å"career ladders† that will require the teachers to continue their education (Blosser, 1989). Most of this educational reform blossomed in the 1980’s, a period which is now referred to as the school reform movement. It was during this time that many of the ideas of educational reform came into public view. Science Teacher Education Most colleges in the U.S. require science teacher candidates to enroll in a vigorous course of study. There are many more areas of study beyond science necessary in order to adequately prepare the students for the teaching world (National Science Teacher’s Association, 2001). For example, at Towson University science education students must complete special education, psychology, communications, and information technology classes in addition to their core science and general education courses. These additional classes help to better prepare the candidates for what they might encounter in the professional world (www.towson.edu, 2001) Certification In the state of Maryland, there are many requirements to receive and hold certification to teach in the state. According to the Maryland State Teacher’s Association, candidates who wish to obtain certification must â€Å"possess an earned bachelor's degree or higher from a regionally accredited institution of higher education in a discipline appropriate to an assignment in the elementary or secondary school curriculum, receive an average of "B" or better in courses related to area of assignment, submit qualifying scores on teacher certification tests- Praxis I and II (Basic Skills and Content tests only), and complete 135 clock hours of study prior to employment as a resident teacher.† Basically, this means that the candidate must attend a four-year school and graduate with a degree. They have to get a B or better in their science and education courses, pass both Praxis exams, and complete one semester of student teaching.

Drilling vs Solar Power

I choose solar power over drilling oil. I chose this â€Å"side† because drilling oil is hazardous to the environment. Solar energy is from energy directly from the sun’s radiation and Drilling is coming from below the ocean floor. The oil spill in the gulf 2010 was devastating to the environment and is still being looked at as one of the worst environmental disasters of all time. Solar power is better for the environment and we can use it for years to come. The key habits for hindering my thinking when looking at the opposing view, was stereotyping that oil drilling is not safe and causes a lot of problems for the environment because of what I heard in the news. I was also was resistance to change, I don’t like change but when it comes to the environment I believe we have to stand up for what we believe in. I also used the â€Å"mine is better habit† where I thought my opinion was the right one until I researched the topic. After researching I found out that oil spills can be devastating to wildlife. Drilling oil creates jobs which is influential for the economy. In return solar power is better for the environment because it uses natural process for energy. In order for solar energy to work you must have temperature, it is an important factor that may affect the performance of solar power. I still believe that solar power is more beneficent because we are protecting our wild life and environment. What I can do to overcome my habits hindering my thinking is to not be resistant to change. Try and not believe that my opinion is the right one, I have to do my research so I can back up what I am saying. Try not to stereotype that all drilling is bad. I need to examine my first impression of the problems and issues. I need to research all views of the situation and then determine what is best. I did research benefits of solar power and drilling and then researched the disadvantages of both I stand by my choice that if I had to choose between the two I would still choose solar power. I found both topics to be intriguing and informative.

Time Management Strategies for Students

Time Management Strategies for Students Time Management Strategies for Students How Not to Let Game of Thrones  Fail Your Exams It’s 9 pm and you got a fresh new season of Game of Thrones to watch! But, first you promise yourself only 1 episode. Half way through the video you are hooked and by the time it ends, you throw your hands in despair, John Snow and the White Walkers! I have got to know what happens next! Soon enough you end up watching the entire series. Whew †¦ That was one hell of a season. You suddenly notice its morning, and remember you have a Math exam just in two hours! Two hours!? It’s all your fault, Starks and Lannisters! It’s a matter of urgency and you can’t let Game of Thrones fail your exams! Well, let’s identify the problem. The challenge you face is poor time management. Time management is simply planning, prioritizing, delegating, controlling, understanding yourself and identifying your problematic habits. Once you know how to manage time you will be surprised how easily you can accomplish a lot of activities in only 24 hours! Planning You need to make a comprehensive plan besides a simple to-do list. Your plan should include how you target to carry out an effective time management routine. Before that find free online resources, read article, books and keep on changing your plan when necessary. Prioritizing Divide your work into four main areas: Urgent Put all the urgent work in this area, for instance, upcoming exams, assignments or quiz. Moreover, allocate the most of your time in this zone. Plan to do This is perhaps the most essential part but you have to give it the second most importance. This part usually includes work that matters to you. For instance, researching or networking with other student, scheduling and planning other work related activities. Reject Explain Put here work that causes useless distractions such as email notification or requests from others. Resist and Cease You must try to spend the least amount of time for work that involves in this region such as meaningless doodles, watching Game of Thrones marathon, or listening to songs. Delegating First, take the free delegation review form to see how good you are in this matter. Second, follow these simple steps in a sequent manner: Define the task Select the individual or team for the assignment Provide resources Delegate the task to the individual or team Make a feedback system Review Controlling You have an effective plan or a routine. What happens when you fail to abide by it? You end up letting Game of thrones fail your exams all over again! You must practice your routine and use your plan in a controlled manner until you are accustomed to it. Understanding yourself Understand yourself and the conditions you work best in. Ask yourself these questions:- Do I study better under pressure? Do I study better in a calm or a busy environment? Which time of the day am I most productive? Identifying problematic habits Everyone has some problematic habits such as procrastinating, checking the phone every 5 min, chatting with friends while working, taking a break every now and then and so forth. You must identify all the awkward habits in order to address these matters as soon as possible. See? Time management is not an impossible task. Once you apply this knowledge as well as other resources available you can easily manage your time and if you are smart enough you might even be successful at acing exams that you claim you have no time to study for! Our term  paper writing service can be very useful for you during your exams in college and university.

Ceremonies And Duties Of A Knight Essays - Knight, Jousting, Squire

Ceremonies And Duties Of A Knight Essays - Knight, Jousting, Squire Ceremonies and Duties of a Knight Introduction Knights were a important part in medieval times. They were used as protection on the manors to stop invading enemies. The worst hated were the Vikings. Knights did more than just sit around and wait for someone to attack them.The trained for when there was going to be a battle and also taught soon to be knights. They also had tournaments for practice and entertainment. Probably the most common tournament known today is jousting. Jousting is where two opponents are on horses going as fast as they can with very big and long poles and try to hit there opponent off of their horse which is also moving and the opponent also has a pole. In the tournaments they first used very sharp and pointy jousting sticks but too many people were getting hurt and no one thought it would be fun to enter a tournament where you get hurt so then everyone agreed to use blunt jousting sticks instead of using sharp pointy jousting sticks so that people wouldn?t get hurt as bad. Jousting then lead to a ! game called tilting that became popular back in the 1400?s. Two knights would be on horses heading towards there opponent in narrow lanes so the horses could not hit into the other horse. The knights would carry jousting sticks and try to hit there opponent of of their horse. There was also many other games that took place at the tournaments like sword fighting and many others. * Training Before becoming a page you would learn take care of the woman in his family.Also during this time he learned how to take care of horses and how to ride a pony.To become a knight you would first have to go through many years of hard work. You would first start of at the age of seven as a page until your teens. During this time a page would learn how to fight with swords and play games that helped him learn strategy and skill. He would also learn how to hunt with birds like hawks and falcons. He also learned manners. When you became a squire you were mainly the knight?s servant. A squire would also take care of prisoners in a battle. A squire had to help out his master. If your master went to war you would have to go to war with him. If your master was hurt you would have to dress his wounds. Then if your master died you would have to make sure that your master had the proper burial grounds and funeral. Then i f your were very good and proved it to your master you might become ! a knight. But becoming a knight just didn?t happen over knight. (That was a play on words.) Becoming a knight didn?t happen until you were eighteen and that was only if you were one of the best pages and squires. Most squires were knighted at a time of peace but some squires were knighted on the battlefield i f they had shown great bravery. The first knighting ceremonies were very simple but then later in time the ceremonies were more complex.For example, in early knighting ceremonies all a knight did was buckle the armor on the squire and he was knighted. In later ceremonies one knight would buckle on the armor and another knight would put on the spurs. The squire then knelt before the knight that was going to knight him. Then the knight would give the squire a blow to the back with his hand. Then the knight tapped the squire on the back again with his sword but he did not cut him because he used the side of the sword that wasn?t sharp. After that the knight said ?I dub you! knight? and then he was a knight. When the knight tapped him with the side of the sword it was called the accolade which means neck from the French word col. When Christianity became more popular Christianity was linked in with knighthood. The night before a knight was going to be knighted he would place his armor on the alter and pray all knight. He also would confess,

Investigation About Forklift Essay Example | Topics and Well Written Essays - 750 words

Investigation About Forklift - Essay Example This essay stresses that the forklift operators must be trained and retrained time again so that they can always remember not to push or shove bins while workers are in front of the line, as this may trigger an accident. In addition, employees have to be keen while working at all times, in this case, if Tina was keen, she would have seen the forklift that is if she did not have her back turned. The forklift operator is normally trained and must have received a tool box talk on not pushing or shoving bins while workers are in front of the line. If proper disaster management were in place medical officers would have been in the place of incident at the right time. This can be attributed to poor event management. Moreover, an accident may be caused by unattended medical issues in employee’s body. This paper makes a conclusion that lack of educating the employees on the safety measures is one of the principal causes of the incident that happened to Mrs. Tina. The accident would be avoided if a proper education was carried out and proper safety equipment put in place. Also, the employees would be in a better place to handle Tina’s case if they had skills in first aid operations. Management should heavily invest in training its employees on the site’s safety program can only be successful when employees on the site receives sufficient training to comprehend what their safety responsibilities and opportunities are and how to fulfill them. Consequently, training forum is a high priority to ensure a safe workplace.

Casual Factors Essay Example | Topics and Well Written Essays - 750 words

Casual Factors - Essay Example mer includes such factors as genetic disposition and peri-natal conditioning, chemical imbalances, damages to the central nervous system, etc., while the latter includes such factors as schooling system, family and other cultural aspects. The remainder of this essay will foray into ways of identifying these factors, their consequences, and ways of mitigating them (Dodge, 1993) Emotional disorders caused by family can take several shapes. For example, a child that is constantly exposed to domestic violence, sexual abuse, excessive insults, constant poverty and loss of a parent can develop symptoms related to anxiety and depressive disorders. Some tell-tale signs of family-induced psychological disorders are: an introverted personality, academic underperformance, poor social skills, juvenile delinquency, etc. Recognizing early signs can be difficult as the affected children can assume a normal external disposition (Dodge, 1993). Usually, the underlying problem comes to light only after a traumatic episode. Nevertheless, child counselors can play a significant role in remedying some of the emotional and behavioral patterns through application of such techniques as Cognitive Behavioral Therapy (CBT), Primal Therapy, etc. Medications such as lithium, Buspirone, Fluoxetine, Bupropion, etc. can also be useful but have to be used with caution. Also, medications d on’t provide permanent cure but only temporary symptomatic relief. Hence, a prolonged counseling regime to change negative cognitive and behavior patterns is the most efficacious of the treatment options (Stewart, 1999). Emotional disturbances that are caused by an unsuitable school environment are similar to those that are caused by chaotic family circumstances. Inappropriate corporal punishments, bullying by peers, lack of proper attention from teachers, etc., can make the child feel sad and lonely. The child is also likely to experience feelings of guilt and worthlessness. The afflicted child