Secure Encounter-based Mobile Social Networks

Secure Encounter-based Mobile Social Networks ABSTRACT: Encounter-based social networks and encounter-based systems link users who share a location at the same time, as opposed to the traditional social network paradigm of linking users who have an offline friendship. This new approach presents challenges that are fundamentally different from those tackled by previous social network designs. In this paper, we explore the functional and security requirements for these new systems, such as availability, security, and privacy, and present several design options for building secure encounter-based social networks. To highlight these challenges we examine one recently proposed encounter-based social network design and compare it to a set of idealized security and functionality requirements. We show that it is vulnerable to several attacks, including impersonation, collusion, and privacy breaching, even though it was designed specifically for security. Mindful of the possible pitfalls, we construct a flexible framework for secure encounter-base d social networks, which can be used to construct networks that offer different security, privacy, and availability guarantees. We describe two example constructions derived from this framework, and consider each in terms of the ideal requirements. Some of our new designs fulfill more requirements in terms of system security,reliability, and privacy than previous work. We also evaluate real-world performance of one of our designs by implementing a proof-of-concept iPhone application called MeetUp. Experiments highlight the potential of our system and hint at the deployability of our designs on a large scale EXISTING SYSTEM: Early work assumed that the parties could communicate over a public but authenticated channel or, equivalently, assumed a passive adversary. This assumption was relaxed in later work, which considered an active adversary who could modify all messages sent between the two parties.In the Traditional Social network site present a dra-matically different set of challenges, not the least of which are security and privacy of users and authenticity of the other party in a conversation. Guarantees that are trivial in traditional social networks, such as authenticity (ensuring one is com-municating with the desired person), become open problems in encounter-based networks. Additionally, requirements like anonymity—a feature that is not needed in most traditional online social networks based on prior face-to-face contact— need to be considered in encounter-based networks. This is desirable because users would expect information about people they happen to meet to stay private. Fu rthermore, since people do not automatically place their trust in others simply based on presence in the same location, it is also desirable to reveal the minimum amount of information required for future secure communication. Sharing detailed personal information is not the primary goal of encounter-based networks, but can of course be easily implemented if both users agree upon the successful verified encounter.. PROPOSED SYSTEM: In proposed system we consider fundamental requirements for encounter-based social networks. We note that in addition to basic functionality like high availability, scalability, and robustness to failure, these systems should provide several security guarantees, including privacy in the form of unlinkability of users sharing an encounter, confidentiality of data exchanged among encounter participants, and authentication of both users in a two-party conversation. We construct a flexible frame-work for secure encounter-based social networks, which can be used to construct networks that offer different security, privacy , and availability guarantees. We describe two example constructions derived from this framework, and consider each in terms of the ideal requirements. Some of our new designs fulfill more requirements in terms of system security, reliability, and privacy than previous work. The first experience of interaction you want to provide an incoming user are the updates and responses about his activity in the system. This keeps the user updated about what’s going on in here. Although encounter-based systems appear very analogous to existing social networks, they present a considerably different set of challenges, out of which are security and privacy of users and authenticity of the other party in a conversation are important. Assurances that are trivial in traditional social networks, such as authenticity (ensuring one is communicating with the desired person), become unwrapped problems in encounter-based networks. Additionally, requirements like obscurity—a feature that is not needed in most usual online social networks based on prior face-to-face contact—need to be considered in encounter-based networks. This is desirable because users would look forward for information about people they happen to meet to stay private. Also, since people do not automatically place their faith in others simply based on presence in the same location, it is also desirable to disclose the minimum amount of information required for future secure communication . Sharing complete personal information is not the primary goal of encounter-based networks, but can of-course be easily put into practice if both users agree upon the successful verified encounter. we consider basic requirements for encounter-based social networks in addition to basic functionality like high availability, scalability, privacy security. We propose specific design architecture for encounter-based social network. In this architecture suggest two possible implementation, each conspicuous a balance between performance and security. To highlights of challenges it was designed for specifically secure centralized server. ARCHITECTURE: MODULES: Privacy or unlink ability. The privacy of two parties sharing an encounter must be protected, even from others in the vicinity who may also participate in simultaneous encounters. In this case, privacy means that an external adversary (even one taking part in the encounter or colluding with a â€Å"bulletin board† or rendezvous server to be used in latter phase) who is not one of the two users of interest should not be able to conclusively determine that two users have made a connection. Authenticity Meaning that when two users decide to make a connection, they should be assured that messages indeed originate from each other. Confidentiality Meaning that information exchanged between two users should be accessible only to them. Availability. As such, the infrastructure to exchange encounter information should be accessible most of the time. The unavailability of individual users should not affect the availability of other users. Since the time at which encounter parties check for potential encounters associated with their activities could be arbitrary, the encounter-based social network is more sensitive to availability than conventional social networks. Scalability. With typical social networks being large in size, any potential social network design, including those based on encounters, should scale to support a large number of simultaneous users. This requires minimizing dependence on a centralized entity.

Fixed Income Securities

ANSWERS TO QUESTIONS FOR CHAPTER 1 (Questions are in bold print followed by answers. ) 2. What is meant by a mortgage-backed security? A mortgage-backed security is a security backed by one or more mortgage loans. Like a bond that is callable, a mortgage-backed security allows the investor to grant the borrower an option. 4. What is the cash flow of a 10-year bond that pays coupon interest semiannually, has a coupon rate of 7%, and has a par value of $100,000? The principal or par value of a bond is the amount that the issuer agrees to repay the bondholder at the maturity date.The coupon rate multiplied by the principal of the bond provides the dollar amount of the coupon (or annual amount of the interest payment). A 10-year bond with a 7% annual coupon rate and a principal of $100,000 will pay semiannual interest of (0. 07/2)($100,000) = $3,500 for 10(2) = 20 periods. Thus, the cash flow is $3,500. In addition to this periodic cash, the issuer of the bond is obligated to pay back th e principal of $100,000 at the time the last $3,500 is paid. 6. Give three reasons why the maturity of a bond is important.There are three reasons why the term to maturity of a bond is important. First, the term to maturity indicates the time period over which the holder of the bond can expect to receive the coupon payments and the number of years before the principal will be paid in full. Second, the term to maturity is important because the yield on a bond depends on it. The shape of the yield curve determines how the term to maturity affects the yield. Third, the price of a bond will fluctuate over its life as yields in the market change.The volatility of a bond’s price is dependent on its maturity. More specifically, with all other factors constant, the longer the maturity of a bond, the greater the price volatility resulting from a change in market yields. 8. Explain whether or not an investor can determine today what the cash flow of a floating-rate bond will be. Floati ng-rate bonds are issues where the coupon rate resets periodically based on a general formula equal to the reference rate plus the quoted margin. The reference rate is some index subject to change.The exact change is unknown and uncertain. Thus, an investor cannot determine today what the cash flow of a floating-rate bond will be in the future. 10. What is an inverse-floating-rate bond? While the coupon on floating-rate bonds reliant on an interest rate benchmark typically rises as the benchmark rises and falls as the benchmark falls, there are issues whose coupon interest rate moves in the opposite direction from the change in interest rates. Such issues are called inverse floaters. 12. (a) What is meant by an amortizing security?The principal repayment of a bond issue can be for either the total principal to be repaid at maturity or for the principal to be repaid over the life of the bond. In the latter case, there is a schedule of principal repayments. This schedule is called an amortization schedule. Loans that have this amortizing feature are automobile loans and home mortgage loans. There are securities that are created from loans that have an amortization schedule. These securities will then have a schedule of periodic principal repayments.Such securities are referred to as amortizing securities. (b) Why is the maturity of an amortizing security not a useful measure? For amortizing securities, investors do not talk in terms of a bond’s maturity. This is because the stated maturity of such securities only identifies when the final principal payment will be made. The repayment of the principal is being made over time. 14. What does the call feature in a bond entitle the issuer to do? The most common type of option embedded in a bond is a call feature.This provision grants the issuer the right to retire the debt, fully or partially, before the scheduled maturity date. 16. What does the put feature in a bond entitle the bondholder to do? An issue wit h a put provision included in the indenture grants the bondholder the right to sell the issue back to the issuer at par value on designated dates. The advantage to the bondholder is related to the possibility that if interest rates rise after the issue date (thereby reducing a bond’s price) the bondholder can force the issuer to redeem the bond at par value. 8. How do market participants gauge the default risk of a bond issue? It is common to define credit risk as the risk that the issuer of a bond will fail to satisfy the terms of the obligation with respect to the timely payment of interest and repayment of the amount borrowed. This form of credit risk is called default risk. Market participants gauge the default risk of an issue by looking at the default rating or credit rating assigned to a bond issue by one of the three rating companies—Standard & Poor’s, Moody’s, and Fitch. 0. Does an investor who purchases a zero-coupon bond face reinvestment risk? The calculation of the yield of a bond assumes that the cash flows received are reinvested. The additional income from such reinvestment, sometimes called interest-on-interest, depends on the prevailing interest-rate levels at the time of reinvestment, as well as on the reinvestment strategy. Variability in the reinvestment rate of a given strategy because of changes in market interest rates is called reinvestment risk.This risk is that the interest rate at which interim cash flows can be reinvested will fall. Reinvestment risk is greater for longer holding periods, as well as for bonds with large, early cash flows, such as high-coupon bonds. For zero-coupon bonds, interest is reinvested at the same rate as the coupon rate. This eliminates any risk associated with the possibility that coupon payments will be reinvested at a lower rate. However, if rates go up, then the zero coupon bond will fall in value because its â€Å"locked-in† rate is below the higher market rate. 22.W hat is meant by marking a position to market? Marking a position to market means that periodically the market value of a portfolio must be determined. Thus, it can refer to the practice of reporting the value of assets on a market rather than book value basis. Marking to market can also refer to settling or reconciling changes in the value of futures contracts on a daily basis. 24. What is risk risk? There have been new and innovative structures introduced into the bond market. Money managers do not always understand the risk/return characteristics of these securities.Risk risk is defined as not knowing what the risk of a security is because those involved in issuing and buying securities are not aware of what can happen. There are two ways to mitigate or eliminate risk risk. The first approach is to keep up with the literature on the state-of-the-art methodologies for analyzing securities. The second approach is to avoid securities that are not clearly understood. 26. What is a pri ce-risk-transferring innovation? A price-risk-transferring innovation is an innovation that provides market participants with more efficient means for dealing with price or exchange rate risk.

The Undisputed Truth About Essay Letter Writing Samples That the Experts Dont Want You to Know

The Undisputed Truth About Essay Letter Writing Samples That the Experts Don't Want You to Know Such letter fall under the class of formal letters. The very first information which you put on an official letter is your name and address. With a wide range of letter writing templates readily available, you can use from a broad assortment of letter formats that may be customizable. Unique styles are typical in formal letters on paper that has the address ready-printed at the very top of the webpage. Letters have played and are still playing an important part in communication across the world. Stay focused on your targets, but in addition on your life. The next thing to do is to demonstrate you have the work ethic, savvy, and enthusiasm it can take to compose a truly tailored cover letter. Write about your function in your loved ones. The 30-Second Trick for Essay Letter Writing Samples Ask for one or more volunteers to speak about how they felt to get the letter. An inform al letter can be written in nearly any way you select, but there are a couple of organizational guidelines you may follow if you're unsure of what to write or the way to format your letter. Opening a letter in the right manner is most important. The experiences you've got and the people that you meet along the way will offer wisdom and insight which you never considered before. Don't wait until you're dying to commence living. You can start to make a list of people 30 people if you wish to send one every day and after that plan out how you're going to send your letters. In any event, you will learn a great deal more about yourself and I feel that's what truly counts in the long run. You may also compose a letter here, this website can help you set the dates to under a year. Show your willingness to be connected with the business in the future and provide your LinkedIn address if you've got one or your email address. The committee is likely to present their approval on Tues day. My report wasn't up-to-date, I will need to revise it tomorrow. As a consequence, letter writing will. What you say will be dependent on the main reason you're writing, so make sure to tailor your letter to fit your own personal and professional circumstance. Letters to strangers often start out with an explanation of the reason behind writing. Single letter writing template is really a good letter that you're able to utilize to set your thoughts into most clear and exact words. The very first paragraph should include an introduction and a concise explanation of your reason behind writing. Remember also that concise does not need to mean bluntyou still will need to consider your tone and the audience for whom you're writing. Asking yourself a few standard questions can be a great method to approach letter writing. Paper letters were once the most and sometimes the sole reliable way of communication between two people in various locations. Writing is a superb method to place your worth into practice. Everything will get much better. In direct mail, you may use emotion. In the end, the tone you take in your letter will help determine if you receive the outcomes you would like. In the event that you were offensive at all, rewrite the letter! Keep in mind it is an official letter, therefore the greeting must be respectful and not too personal. If you're fond of writing a good deal of letters to your nearest and dearest or friends then grant writing template is appropriate for you. Prior to starting, bear in mind a fantastic understanding of suitable spelling, punctuation and grammar may be a real boost to both your business writing and the true success of your enterprise. Along with single word transitions like so'' and and'' there are a variety of excellent transitional phrases which can be used quite effectively. By building a template, in regards to crafting the (nearly) inevitable next job program, you are going to be saving yourself a lot of time and stress. If you intend on mailing your letter, consider sealing it by old-fashioned sealing wax or stickers. Since it's the most crucial line in your whole letter. The aim of the letter should be produced clear in the very first paragraph itself. Skip a line and start the letter. The One Thing to Do for Essay Letter Writing Samples If you want additional info, or when you have any comments or questions, then get in contact with our customer service department today. Include personal offer and data value The start of your cover letter should contain your own personal and contact info, along with the contact information of the continuing organization. Not including a covering letter will most likely guarantee that you won't be regarded as as it shows a deficiency of interest as will using an extremely generic and non personalized letter. Handwritten letters offer you emotional advantages that were identified by psychologists and health-care professionals.

The Financial Aspect On An Incorporated Entity Finance Essay - Free Essay Example

Sample details Pages: 8 Words: 2366 Downloads: 3 Date added: 2017/06/26 Category Finance Essay Type Narrative essay Did you like this example? Let me first begin by explaining what a cash flow statement is. To put it simply, a cash flow statement is rather self-explanatory in that it details the flow of cash in and out of the business. It shows where cash comes from and where the said cash goes to. Don’t waste time! Our writers will create an original "The Financial Aspect On An Incorporated Entity Finance Essay" essay for you Create order For example, a typical cash flow statement would include cash generated from sales and on the flip-side, taxes that are paid. Another form of financial statement is the income statement. The income statement is also sometimes referred to as the profit and loss statement. As with cash flow statements, income statements are also rather self-explanatory. This is perhaps more apparent to the layman if they are referred to as profit and loss statements. These statements show whether a company is running on a profit or a loss for a given period. As with other forms of financial statements, balance sheets also reflect on the financial health of the company. However, balance sheets are typically much more comprehensive and often offer a more detailed look at a companys financial standing. It details who owes the company what, who the company owes, and what properties the company owns, amongst other things. Equity statements on the other hand explains the changes in the companys reta ined earnings. It would typically contain items such as changes in ownership stake in the company and the level of profit or surplus retained over a specified period. Also often detailed are dividend payouts and issuance of stocks. Now armed with some rudimentary knowledge of what financial statements are, we are perhaps better equipped to navigate towards the main focus of this essay the importance of financial statements to various groups. Investors In no particular order, I shall first discuss the importance of financial statements through the lens of a prospective investor. As one might imagine, it would probably not be a very good idea to invest ones hard earned money into a financially ill business. In a nutshell, this is why financial statements bare such great importance to the prospective investor. Financial statements provide a vital look into the inner workings of a business, painting a better picture of how the said business is run and thus helping investors better calculate risk. That in turn helps them make better investment choices, hopefully. For instance, an analysis of an income statement would show whether or not the target of investment is turning a profit. This, is probably as good a yardstick as any in assessing a companies success, at least on the surface. Cash flow statements are also of considerable importance to prospective investors as it displays the the movement of cash through the business. An investor could use the cash flow statement in tandem with the the companies net income to determine whether the volume of cash moving through the company is sufficient to make their investment efforts worthwhile. Balance sheets as discussed above, provide a snapshot of a companies financial wellbeing for a specific duration of time. Balance sheets thus provide integral data detailing the assets of a business which would include prior investments contradicted with the liabilities the business owes. Based on the assumption that no self-respecting investor would want to make a loss on his/her investment, the balance sheet would show clearly if the business in rolling in debt with not much prospect of profitability and that point in itself clearly underlines the importance of the balance sheet to investors. Equity statements like all other forms of financial statements really come in handy when trying to assess the financial standing of a company. Equity statements are used typic ally, but not exclusively, when deducing a companys debt-to-equity ratio. The investor would look at the equity statement and draw a comparison between the companys cumulative debt and the shareholders equity. This helps paint a detailed picture of a companys financial health, specifically and for lack of a better word, its investability. Employees It is often said that a company is but only the sum of its employees. Having argued thus, it is a hardly debatable notion that financial statements are as important to individual employees as they are to anyone. Financial statements can help the individual employee gauge the stability of their current job and decide if it is necessary to perhaps seek greener pastures elsewhere. Now, this might not necessarily be good for the business in question, but from an employees perspective it is a perfectly valid point. Wouldnt you want prior knowledge if the business you work for was free-falling down the financial hill? Additionally, these reports also come in handy when making bargaining agreements with the management in terms of remuneration, promotions and so forth. It is worth nothing, however, that it is these financial statements are more commonly reviewed by workers unions or similarly designated bodies rather that the individual employee himself. Specifically, balance sheets are important as it helps the employee assess the financial stability of the firm he or she is working for. For instance a registered union may review a companies balance sheet and notice that it has $500million in available cash. The union representative may then attempt to persuade the company to raise employee salaries by a margin realistically within the companys financial parameters, say by 5 percent, knowing full well that the raise would only cost the company and additional $2million. A labor representative may also analyze a companys income statement to weigh revenue and expense levels. Taking into consideration the breakdown of the income statement the representative could show, if it is the case, that perhaps salaries of employees only constitute a proportionally small percentage of the companies expenditure. The said representative could then advocate for a raise on behalf of the employees arguing that the cost involved with giving that raise would not adversely affect the company but rather benefit the firm by boosting the morale and hence effectiveness of its staff. Much of the same arguments as to why an employee or a union would want to review a business income statement conveniently also applies to cash flow statements. The differing point here being that what would be reviewed in a cash flow statement is the companies operating cash activities. Its importance towards the employee would be that cash flow statements would show the total cash payments against which total staff salaries could be compared with to gauge whether employees of the business are being fairly compensated. Equity statements on the other hand, are not of much use to the average individual employee. However, the same cannot be said for workers unions. As equity statements would detail things such as dividend payouts, it would show if the directors are being paid massive dividends at the expense of the average employee as was the case with General Motors during the a utomotive industry meltdown last year. Top execs were paid bonuses worth hundreds of millions of dollars while the company as a whole was so deep in financial quicksand that it required a bailout from the US federal government. Lenders Thirdly, we shall consider the importance of financial statements from the perspective of lenders. As providers of capital, lenders namely banks and financial institutions are understandably very concerned with a companys financial health as it reflects directly on the aforementioned companys credit worthiness. Much like how you and I are required to produce income documents upon application of a loan or any other credit facility for that matter, company owners are also usually required to produce a whole bevy of financial statements before any form of credit is issued by the lender. These documents prepared to certain industry standards serve to paint as accurate a picture as possible of the companys current financial standing and when extrapolated help predict how the company will perform for the tenure of the loan. The balance sheet, by detailing a companys asset investments paint a great portion of this picture. Since the balance sheet also list a companys outstanding debt a nd equity components, it helps creditors assess their relative position amongst the rest of a companys capital composition. On the other hand, profit and loss statements or income statements, are of much use to creditors as it would show whether a company has sustained growth or suffering a loss over a specified period. This then assist the lender in plotting the trend which they will then use, in conjunction with other factors to determine how well the company will be able to repay the loan. As with other financial statements, cash flow statements also prove to be of great importance towards creditors in much the same way as the other forms of financial statements discussed above in that it paints a picture of a companys credit worthiness. However, it is worth noting that a paradox exist when it comes to cash flow statements and its relationship with lenders. The more detailed the cash flow statement is, the less likely the applicant business has anything to hide. Bearing thi s in mind, the cost of preparing a financial statement rises exponentially with the level of detail involved. This increase in cost is associated with the practical and logistical constraints of compiling every single cash transaction that the business undertakes. Thus said, it is of utmost importance that businesses strike the golden balance between cost and providing lenders with a sufficient cash flow information within the statement. Suppliers Apart from the aforementioned parties, suppliers also have an interest in the analysis of a companys financial background via financial statements. Suppliers and vendors rely on the statements to asses the financial standing of clients, especially those they intend on establishing a long-term relationship with, to ensure that they are not getting into a bad deal. However, setting themselves apart from the parties discussed above, suppliers tend to rely more on statements containing information on the business partners or owners. The underlying principle behind this phenomenon is the fact that in a trade environment where it would be logistically impossible to check their customers backgrounds in its entirety, credit risk on the part of supplier simply skyrockets. This information is typically used as part of the suppliers due diligence and compliance processes, which are crucial in identifying the risk involved in transacting with a particular client. When these processes are undertaken are largely dictated by the suppliers themselves, however it may also be determined by government or industry regulators. For example, when not governed by regulation, a supplier may choose to play it safe by implementing due-diligence processes prior to establishing a relationship with the client business or only once transactions hit a certain threshold to give clients a chance to sample a vendors goods or services. Another peculiarity with the way vendors or suppliers utilize financial statements is that they generally tend to rely on specific, isolated bits of informations within these statements when financially profiling their clients. These bits might take the form of bankruptcy flags deduced from balance sheets, liquidity data inferred from cash flow statements and even financial statements with an internal focus which they then use to evaluate whether a clients business model is a potentially profitable or otherwise. However, where available, income statement s would be favourable as they negate the need for guess work in determining a client business profitability. Customers Moving on, we shall now consider the importance of financial statements towards the stakeholders perhaps most coveted by businesses the valued customer. Whilst the layman would rarely look into each type of financial statement in isolation, when consolidated and simplified, perhaps into a financial report or an article found in he business section of the daily paper, the information in financial statements can be extremely useful to the consumer. Allow me to illustrate my point. Consumers no doubt prefer doing business with well established companies as these businesses generally offer better after sales service and customer support. However, in some sectors like the automotive and real estate industries, longevity in a company is often at top of a consumers priorities when faced with the choice of who to do business with. Information hypothesized from financial statements provide this valuable insight. Another prime example I shall use to fortify my point has to do with the recen t surge in environmental awareness. Today, more consumers than ever are demanding that companies behave socially and environmentally responsibly. As a direct result, more and more companies are incorporating such metrics into their financial documents to reflect this much desired virtue. Government Lastly, a companys financial statements also play an irreplaceable role to the governments of the nations in which the companies operate. It is common knowledge that a great portion of a governments income comes from corporate tax paid by businesses that operate in that country. Thus, financial statements allow governments the luxury of calculating future budgets by way of approximating the taxes that each company would pay based on its prior and projected performance. In more detail, companies balance sheets are scrutinized by government agencies and regulators to ensure that companies are being run in compliance with legislation passed by the government. On a darker note, law enforcement often analyzes the cash flow statements of companies as it details the migration of cash in and out of the company. As such, this document would be as good as any when looking for evidence of money laundering. Conclusion Dearest reader, much ink has been spilled by both scholars and members of industry alike in an effort to classify financial statements into various groups. Although this has largely been a successful endeavor as discussed in the foreword of the essay, the more minute details of what each type of financial statement is remains till this day a subject of debate and interpretation. Perhaps, though, a more futile question to ask is to whom are financial statements important?. To that question and in concluding this essay, I humbly opine that while financial statements are important to several major groups as outlined throughout the essay, on a broader scale, these mere pieces of paper with numbers jotted across them would be of great importance to any group or individual with an interest in the economic aspect of any particular company.