What Do You Mean By Hash Information Technology Essay

What Do You Mean By Hash Information Technology Essay A hash also called a digest, and informally a checksum is a kind of signature for a stream of data that represents the contents.  The closest real-life analog we can think is a tamper-evident seal on a software package: if you open the box (change the file), its detected. A  cryptographic hash function  is a  deterministic procedure  that takes an arbitrary block of  data  and returns a fixed-size  bit string, the (cryptographic)  hash value, such that an accidental or intentional change to the data will change the hash value. The data to be encoded is often called the message, and the hash values are sometimes called the  message digest  or simply digest. The ideal cryptographic hash function has four main or significant properties: It is easy to compute the hash value for any given message, It is  infeasible  to find a message that has a given hash, It is infeasible to modify a message without changing its hash, It is infeasible to find two different messages with the same hash. Cryptographic hash functions have many  information security  applications, notably in  digital signatures,  message authentication codes  (MACs), and other forms of  authentication. They can also be used as ordinary  hash functions, to index data in  hash tables, for  fingerprinting, to detect duplicate data or uniquely identify files, and as  checksums  to detect accidental data corruption. Indeed, in information security contexts, cryptographic hash values are sometimes called (digital) fingerprints,  checksums, or just  hash values, even though all these terms stand for functions with rather different properties and purposes. Q2. What are the principal elements of a public-key cryptosystem? Ans2. Public-Key Cryptosystems: Secrecy and Authentication, illustrates the essential elements of a public-key encryption scheme. Public key cryptography is an asymmetric scheme that uses a  pair  of keys for encryption: a  public key,  which encrypts data, and a corresponding  private,  or  secret key  for decryption. You publish your public key to the world while keeping your private key secret. Anyone with a copy of your public key can then encrypt information that only you can read. Even people you have never met. Plaintext: This is the original message or data fed into the algorithm as input. Encryption Algorithm: It performs various substitutions and transformation on plaintext. Secret Key: It is used for encryption. Ciphertext: This is the scrambled message produced as output. Decryption Algorithm: This is the encryption algorithm run in reverse. Q3. What types of information might be derived from a traffic analysis attack? Ans3. In a connection-oriented application, the frequency and duration could be determined. In either a connection-oriented or connectionless environment, the number and length of messages between parties could be determined. Traffic analysis attacks aim to derive critical information by analyzing traffic over a network. The two classes of traffic analysis attacks: link-load analysis attacks and flow-connectivity analysis attacks.   Countermeasures for such attacks are usually realized by properly padding the payload traffic so that the statistics of the overall traffic become significantly different from that of the payload traffic. Two basic countermeasure strategies are (a) to pad the traffic with constant inter-arrival times of packets (CIT) or (b) to pad the traffic with variable inter-arrival times (VIT).   Q4. What are three broad categories of applications of public-key cryptosystems? What requirements must a public key cryptosystems fulfill to be a secure algorithm? Ans4. Public-key systems are characterized by the use of a cryptographic type of algorithm with two keys. Depending on the application, the sender uses either the senders private key or the receivers public key, or both, to perform some type of cryptographic function. In broad terms, we can classify the use of public-key cryptosystems into the three categories: à ¢Ã¢â€š ¬Ã‚ ¢ Encryption/decryption: The sender encrypts a message with the recipients public key. à ¢Ã¢â€š ¬Ã‚ ¢ Digital signature: The sender signs a message with its private key, either to the whole message or to a small block of data that is a function of the message. à ¢Ã¢â€š ¬Ã‚ ¢ Key exchange: Two sides cooperate to exchange a session key. Several different approaches are possible, involving the private key(s) of one or both parties. Some algorithms are suitable for all three applications, whereas others can be used only for one or two of these applications. Public key schemes are no more or less secure than private key schemes in both cases the size of the key determines the security. But with public key schemes at least there is usually a firmer theoretical basis for determining the security since its based on well-known and well studied number theory problems. In order to solve the key management problem, the concept of public-key cryptography was introduced. Public-key cryptosystems have two primary uses, encryption and digital signatures. In their system, each person gets a pair of keys, one called the public key and the other called the private key. The public key is published, while the private key is kept secret. The need for the sender and receiver to share secret information is eliminated; all communications involve only public keys, and no private key is ever transmitted or shared. In this system, it is no longer necessary to trust the security of some means of communications. The only requirement is that public keys be associated with their users in a trusted (authenticated) manner (for instance, in a trusted directory). Anyone can send a confidential message by just using public information, but the message can only be decrypted with a private key, which is in the sole possession of the intended recipient. Furthermore, public-key cryptography can be used not only for privacy (encryption), but also for authentication (digital signatures) and other various techniques. Q5. What is digital signature standard? Ans5. This Standard specifies a suite of algorithms that can be used to generate a digital signature. Digital signatures are used to detect unauthorized modifications to data and to authenticate the identity of the signatory. In addition, the recipient of signed data can use a digital signature as evidence in demonstrating to a third party that the signature was, in fact, generated by the claimed signatory. This is known as non-repudiation, since the signatory cannot easily repudiate the signature at a later time. This Standard specifies algorithms for applications requiring a digital signature, rather than a written signature. A digital signature is represented in a computer as a string of bits. A digital signature is computed using a set of rules and a set of parameters that allow the identity of the signatory and the integrity of the data to be verified. Digital signatures may be generated on both stored and transmitted data. Signature generation uses a private key to generate a digital signature; signature verification uses a public key that corresponds to, but is not the same as, the private key. Each signatory possesses a private and public key pair. Public keys may be known by the public; private keys are kept secret. Anyone can verify the signature by employing the signatorys public key. Only the user that possesses the private key can perform signature generation. A hash function is used in the signature generation process to obtain a condensed version of the data to be signed; the condensed version of the data is often called a message digest. The message digest is input to the digital signature algorithm to generate the digital signature. The digital signature is provided to the intended verifier along with the signed data. The verifying entity verifies the signature by using the claimed signatorys public key and the same hash function that was used to generate the signature. Similar procedures may be used to generate and verify signatures for both stored and transmitted data. Q6. Explain authentication function: message encryption, message authentication code and hash function. Ans6. Message encryption: Message encryption is a process that encodes the data of a message so that unauthorized people cannot access it. The process of message encryption converts a message from readable text to scrambled or enciphered text, thus keeping the message content private. Only people who use a private key can read such a message. In fact, message encryption not only safeguards the message but also any attachments included with it. Therefore, message encryption is basically information scrambling, and the technology this process involves is very important for internal security in information technology-driven environments. When message encryption is properly used in such an environment, it helps establish a secure communication channel even in cases where the fundamental system and network infrastructure is not very secure. It is obvious that message encryption is of great significance when a message needs to be transferred through shared systems or network segments in which a number of people may otherwise be able to view it. Message encryption is an invaluable tool in situations where sensitive information needs to be safeguarded so that it cannot be seen or modified by other parties. Message authentication code: One of the reasons that encryption mechanism does not provide a good solution for message authentication is that it is difficult for the receiver to identify the legitimate plaintext. To address this problem, we can apply an error detection code to the message so that only legitimate plaintext can pass the error detection. Such error detection codes are used in the network communication to provide data integrity verification against bit errors introduced by communication channel noise. But it can not provide data integrity protection against malicious attackers. In light of error detection code, we can design a code that uses a secret key. Without the key, modifying the message in a way that it matches the code is impossible. This idea leads to the design of message authentication code (MAC). A MAC  algorithm, sometimes called a  keyed  (cryptographic)  hash function, accepts as input a  secret key  and an arbitrary-length message to be authenticated, and outputs a MAC (sometimes known as a  tag). The MAC value protects both a messages  data integrity  as well as its  authenticity, by allowing verifiers (who also possess the secret key) to detect any changes to the message content. Hash Functions: A hash function H is a transformation that takes a variable-size input m and returns a fixed-size string, which is called the hash value h (that is, h = H(m)). Hash functions with just this property have a variety of general computational uses, but when employed in cryptography the hash functions are usually chosen to have some additional properties. The basic requirements for a cryptographic hash function are: the input can be of any length, the output has a fixed length, H(x) is relatively easy to compute for any given x , H(x) is one-way, H(x) is collision-free. A  hash function  is any  well-defined procedure  or  mathematical function  that converts a large, possibly variable-sized amount of data into a small datum, usually a single  integer  that may serve as an  index  to an  array. The values returned by a hash function are called  hash values, hash codes,  hash sums, or simply  hashes.

Essay --

Based upon the assessment of these important aspects, therapist psycho-educate the family and adolescent about the important findings of the detailed interview and plan out the intervention. Case example of assessment findings in obese adolescent girl: The mother of a 12-year-old girl came for consultation for her daughter’s weight concerns and comments that the girl is concerned about her weight and is being teased about this at school and in the family. There is a family history of obesity in parents and grandparents. During the assessment it was found that the girl’s main interests are sedentary activities like watching T.V., internet use and playing video games. Physical activity is limited, ‘screen time’ is 4-5 hours a day and dietary habits put her at risk of weight gain (skipping breakfast, frequent snacking, consuming soft drinks, and high preference of junk food). The girl has not attained menarche and has a BMI above the 95th percentile on the US-CDC growth chart and normal lipid profile, liver function test, glucose and insulin levels. On psychosocial assessment, she was found to be anxious and depressed due to her increasing weight, body image concerns and previous failed attempts of weight lo ss. She lost her confidence and has low self esteem. She indulged in emotional eating as well to overcome her stress. She has fewer friends as most of the people tease her about her weight. So she prefers to stay alone Impression: Obese with high risk of further weight gain and psycho-social problems. Components & Structure of Cognitive Behaviour therapy There is enough evidence to support the effectiveness of comprehensive behavioural intervention program that include dietary modification and exercise routine as treatment of ... ...cific and realistic goals that can be easily measured (e.g. walking/ running for 40 minutes, five times per week). Give them rewards for achieving goals. 9. Don’t use food as reward. 10. Limit sedentary behaviour Limiting television/computer/video game time gradually from 3 hours/day to 2 hours/day, finally to 1 hours/day (most of the time the strategy of reducing children’s sedentary behaviour can be more effective than a strategy of promoting physical activity). 11. Teach self monitoring to the child Give responsibility to monitor his/ her eating behaviour and physical activity by maintain logbooks/ diaries. Verbally praise the child for taking responsibility. 12. Enhance open communication with the child Let the child be comfortable in sharing his/her feelings with you because many a times child would resort to food to overcome these negative emotions/feelings.

Recruiting and Team Building for Angel Springs Care Essay -- Human Res

Recruiting and team building for Angel springs care Recruitment and selection is a process that takes place at every plane of an organization and is among matters of utmost importance in human resource management. It refers to the process of drawing, ascertaining their competencies, and choosing the individual who fits the job. The process is often the first move towards instituting the competitive power and the essential precedence for the organisations and considering the current global situation, every recruit should thus be most fitting to enable build an effective team (Nankervis, Compton & Morrissey, 2009, p. 15). Some employers dwell only on qualifications and past experience of the applicants so much that additional initiation and guidance is deemed irrelevant. How the job is to be handled is overlooked while professionalism is overemphasized. However, in health and social care organizations just like in many other organizations, recruitment goes beyond acquainting the new employee to co-workers, laying down the basic operations and practices of the place of work (Belbin, 2000, p. 5). Recruitment constitutes an organized operation ranging from rooting the prospective suitors to organizing and carrying out the interviews. The process also demands a lot of time alongside a variety of resources. Fundamentally, a recruitment process involves job evaluation, sourcing, screening and selection and orientation. Job analysis involves documenting the existing or expected job requirements (Nankervis, Compton & Morrissey, 2009, p.27). This is encompassed in a job description and gives the limits and aims of the quest. This majorly comprises a combination of duties carried out previously and there’s need to update them before to en... ...the productivity of the old and new employees under one environment. Since individuals don’t often achieve much in isolation, team work becomes of utmost importance to ensure that the diverging talent of employees is incorporated and harmonised towards a good and common cause. Team building strategies ensure that this is possible as strong teams give a fundamental, reliable source of lasting competitive edge for healthcare organizations. Works Cited Belbin, R. M. (2000). Beyond the team. Oxford: Butterworth-Heinemann. Hough, M. (2002). Group work skills and theory. London: Hodder Arnold. Nankervis, A., Compton, R. & Morrissey, B. (2009). Effective Recruitment and Selection Practices, 5th ed. Albany, NSW: CCH Australia Limited. Pedler M, Burgoyne J and Boydell T. 2007. A Managers guide to self-development. Manhattan, NY: McGraw Hill- Education.

Meaning of Life and Fast Lane Essay

Good coop, bad coop situation. leave well enough alone | let well enough alone Meaning: If you leave well enough alone, or let well enough alone, you don’t try to improve or change something that’s already good enough. For example: The kids seem happy enough now so let’s just leave well enough alone and forget about finding a new school for them.? skate on thin ice- Meaning: If you’re skating on thin ice, you’re doing something risky, or you’re in a situation that could quickly become dangerous. Jockey for position- Meaning: If you jockey for position, you try to get yourself in a good position in relation to others who’re competing for the same opportunity or the same goal. let the cat out of the bag – Meaning: If you let the cat out of the bag, you let someone know a secret. You could have knocked me over with a feather. – Meaning: You can say â€Å"you could have knocked me over with a feather† to show how surprised you were when something happened, or when you heard about something. add fuel to the fire If you add fuel to the fire, you do something to make a bad situation even worse. ahead of the game You are ahead of the game if you have an advantage over your competitors in any activity in which you try to do better than others, such as in business, academia, sports, etc. all the rage Informal If something is all the rage, it’s very popular or it’s in fashion at the moment. asking for trouble If someone is asking for trouble, they’re doing something risky that could lead to a problem. itchy feet Informal If you have itchy feet, you feel the need to go somewhere different or do something different. in the long run If you talk about something â€Å"in the long run†, you mean over a long period of time. At cross-purposes If you’re at cross-purposes with someone, you think you’re both talking about the same thing but you’re actually talking about different things. at loose ends If you’re at loose ends, you feel restless and unsettled because you don’t have anything to do. a blessing in disguise You can say something is a blessing in disguise if it appears to be bad at first, but it results in something very good in the end. back to square one If you have to go back to square one, you have to stop and start again, usually because something isn’t working as well as expected. bite your tongue | hold your tongue If you bite your tongue, or hold your tongue, you force yourself not to say something you really want to to say. the icing on the cake | the frosting on the cake If something is the icing on the cake, or the frosting on the cake, it makes a good situation or a good result even better. joie de vivre If you have joie de vivre, you feel the joy of living. make hay while the sun shines If you make hay while the sun shines, you make good use of the chance to do something while it lasts. Fast friends good, loyal friends. The two of them had been fast friends since college. See also: friend fast one a clever and devious trick. (Compare this with pull a fast one. ) That was a fast one. I didn’t know you were so devious. This was the last fast one like that you’ll ever catch me with. life in the fast lane a very active or possible risky way to live. (See also in the fast lane. ) Life in the fast lane is too much for me. See also: lane, life make short work of something to deal with or finish something quickly We made short work of the food that was put in front of us. fast and furious if an activity is fast and furious, it is done quickly and with a lot of energy The first half of the game was fast and furious with both teams scoring three goals each. Ngn av dessa till din story a queer fish Meaning: If someone’s a queer fish, they are a bit strange and can sometimes behave in an unusual way. For example:Your great grandfather was a queer fish, Johnny. He used to write funny poems and then he’d read them aloud to everyone on the train on his way to work let the cat out of the bag Meaning: If you let the cat out of the bag, you let someone know a secret. For example: We’d planned a surprise party for Donna, but some guy she works with let the cat out of the bag, so now she knows.? Don’t forget that this is a secret, so whatever you do, don’t let the cat out of the bag.? †There? s an elephant in the room† – Meaning: If you make a killing, you make a lot of money from a sale or a deal of some sort. For example: My aunt made a killing when she bought some shares in a company as soon as they were issued, and sold them a few weeks later for three times what she paid.? Lots of people made a killing when property values went so high back in the nineties. †Bark is worse than his bite†, †put your money where your mouth is† – prove it.. alot of not air? all hell broke loose Meaning: You can say â€Å"all hell broke loose† if a situation suddenly became violent or chaotic. Bad news travels fast ’ â€Å"Bad news† means news about â€Å"bad† things like accidents, death, illness etc. People tend to tell this type of news quickly. But â€Å"good news† (passing an exam, winning some money, getting a job etc) travels more slowly. Least said soonest mended Possible interpretation: When we do or say something bad to someone, a long apology and discussion does not help. In such a case, the less we say the better. It’s written all over your face. If you say â€Å"it’s written all over your face†, you’re saying that the expression on someone’s face is showing their true feelings or thoughts. Group 20 ENOUGH IS ENOUGH Words Relating to More Than Enough (did you get it? ) ample copious lavish myriad plethora profuse prolific superfluous surfeit Memory tips: use these mnemonics (memory devices) to boost your vocabulary. Make up your own memory clues for words in this lesson that are personally challenging. Add these tips-and your own-to your Vocabulary Notebook. Copious let yourself see the word copies within copious, and think â€Å"lots of copies. † Certainly â€Å"lots of copies† leads to the defining ideas of abundant and plentiful. Plethora Let the ple lead you to plenty. When you write plethora in your Vocabulary Notebook, underscore the ple with a colored pen or marker. Superfluous The prefix super means over and above. This knowledge is helpful because superfluous means â€Å"above what is needed; extra. â€Å" Surfeit Like super-, sur- is also a prefix meaning over and above. So a surfeit is an amount over and above what is needed. Using apperception, (http://www. merriam-webster. com/dictionary/apperception) link a word you most likely already know, surplus, to the new word, surfeit. These two-syllable synonyms even have the same number of letters! Solidify the meaning of surfeit in your memory. Ample think of the word sample but get rid of the S. and since Ample means more than enough you can think of many samples! Lavish think of marangsvisch with lakris sas! And put the letters LA from the word Lakris instead of S. Profuse(overflodande) think about refuse and proactive, because proactive is â€Å"overflowing† with vitamins. Change the re to pro Prolific, the word productive has the same meaning, so take the PRO from productive and add it with lyric which at least makes me think of lific. So think productive lyric. Myraid (skiftande mangd) think My ride†¦ Group 19 (2nd cluster for Fall Term) Wonderful You Are! Words Relating to Praise and Respect (did you get it? ) Acclaim accolade adulate esteem eulogize exalt extol laud panegyrize revere venerate Laud If you know applaud, then simply connect the new word laud to the word you already know, applaud. The meanings of these two verbs are closely connected. Plaudits means praise. Revere You remember Paul Revere from American History, right? Now, I am sure you’ll agree that it’s only right to respect, or revere one of our nation’s Founding Fathers! Another tip: you can repeat this chant to yourself over and over â€Å"Revere the Reverend. Revere the Reverend. Revere the Reverend† Acclaim think of ass, but with cc, and slajm (slaim)! Accolade think of assa, but with cc and chocolade Adulate ad-ul-ate Esteem think of S team, but with double e Eulogize think ekoloogisk / EU logisk Exalt think Exaltera, without era, since exalterad means vara upprymd like exalt. Extol, ex stol Panegyrize think, pannkakor & risgrynsgrot Venerate Think â€Å"ata vanner†, but switch place, let vanner lead you 2 Vener, and ata-ate.

English Is Important for Our Daily Life Essay

As we all know, English is the one of important language in this world. If we cannot speak English even a little bit, we are called as a very poor in this community. We also cannot improve our life if we worst in English. We will feel loser if we in the group that use English as a medium to speak. According to the research that have been made by the group of University Malay, 70% of undergraduate student especially Malay student are not use English as a medium to speak. It’s show that most of the student do not want to use English as a main language in their life. People always said that we must use our country language so that it indicate we love our country. The statement is not fault but we also must learn English for our future life such as to find a job, to communicate with foreigner, easy to understand if we find information through online and easy for student to survive in university life because most of the university in Malaysia use English as a medium to speak. One of the reason why we must learn English in our daily life is English is important to get a job. In this era, many people are jobless even though they have a degree. It is because they do not have a soft skill. Even though we got the best result in examination but we cannot speak in English, it is hard for us to find a job. Example is, if we want to work with a giant company such as Petronas, Sime Darby, Schlumberger and etc we need to face many process. One of the process is interview. Interview is one of the important process for us to face if we want to work with a giant company. Many giant company have a francais at the other country. So, they use international language that is English as a medium to communicate among the others. Therefore, they must do an interview in English to find an employee. If we have a soft skill like can speak fluently in English, the company will not hesitate to take us as one of their employee.

The use of foul language Essay Example | Topics and Well Written Essays - 500 words

The use of foul language - Essay Example Tracing the origin of the rise of foul language is a very easy task since a quick click of the remote control will you lead you to a world where the utterances of defamatory, explicit, foul language is as natural as breathing. Foul language has already invaded our living rooms and learning it will take only a few minutes. Hence, it is imperative that the government puts into practice laws to control public use of bad language. The first step that our law enforcers should do is to discuss with the students and school authorities ways which could prevent students from using bad language to each other. As the students and the young people are the ones who spend the most time watching TV, they are also the ones who use foul language the most. What's worse is that, many students use defamatory and abusive expressions to each other which sometimes cause deeper problems such as fighting and bullying. School authorities, enforcers and students should make agreements to set up the rules with regards the avoidance of abusive language within the school premises.

Commanding officer Personal Statement Example | Topics and Well Written Essays - 1750 words

Commanding officer - Personal Statement Example As a commanding officer of the 103rd precinct, I am responsible for crime within the district. This 103rd precinct refers to a multi-cultural command around the area. The neighborhoods in these areas comprise of Hollis Park Gardens, downtown Jamaica Business District, Lakewood, Jamaica and Hollis. As a commanding officer of this area, I am responsible for all the crimes that take place within these neighborhoods. In addition, I also shoulder the responsibility of the quality of life within these societies, community affairs, and the level of crime within the community, which is at an all time high. As the new commanding officer of this 103rd precinct, have come up with a number of solid measures that will enable me to control the levels of crimes within these regions, as well as, ensure that the community is a safe and peaceful place to reside, with reigning peace and safety (Addington and Lynch 280). The level of crime within my precinct is very alarming to the extent that some old folks are contemplating moving out of the neighborhoods to safer regions. The region has a wide variety of crimes, which include felony assaults, auto theft and carjacking, burglaries and robberies, street mugging, and rape cases are very common in the area. In addition to these petty crimes, the region also has hardened gangsters who conduct daylight robbery, and fail to consider the quality of lives that they take away in the course of their theft or robbery escapades. All these criminal activities make the region an unsafe place to reside, as well as, a poor place for investments or any other business activity (Eterno and Silverman 66). My responsibilities as the commanding officer of this region are to reduce to a manageable level the rate of crime in the region, as well as, make the region conducive for both habitation and business investments purposes. The first way of reducing these crimes is to analyze the reason and cause behind each criminal activity. Research from crime s tats of the region provides that the main reason why the region has a high level of crime is the lack of proper policing activities in the region. The area has a low ratio of police to citizens. The recommended ratio of police to citizens in this region is three police officers for every VIP, and one police officer for every 750 commoners. However, the current statistics of police to the public provide two police officers for every VIP and one police officer for one thousand five hundred common citizens (Kalinich, Klofas and Stojkovic 45). I intend to increase these ratios of police to the public to the recommended levels. Having the right numbers of police patrolling the region will lead to a considerable reduction of crime in the region. Furthermore, the police we have in the region, the lesser the levels of crime as criminals will feel afraid to perpetrate their criminal activities around a law-enforcing officer. In addition, the public will also feel protected and secure to carr y on their day-to-day activities because of the assured security provided by police patrolling in their neighborhoods. These police department will station posts at strategic points in the region, with special considerations of regions that have high rates of crimes such as ghettos, shanties and slum regions. These officers will also conduct 24/7 patrols across the entire region in order to apprehend criminals who might be robbing or stealing, as well as, maintain general security of the area (Sutton and Trueman 14). The next step of reducing crime in my region will be to introduce a community-policing program. This is a program, which will initiate a unique relationship, as well as, a cooperation pact, between the police department and the public. Through this policy, I intend to bring the police closer to the public and foster a close-knit relationship between these two centers of the community. The resultant effect will be the creation of confidence, trust and loyalty between the two parties involved. As such, it will be