Ensuring the usefulness of electronic data sources while providing necessary privacy guarantees is an important unsolved problem. This problem drives the need for an analytical framework that can ...quantify the privacy of personally identifiable information while still providing a quantifiable benefit (utility) to multiple legitimate information consumers. This paper presents an information-theoretic framework that promises an analytical model guaranteeing tight bounds of how much utility is possible for a given level of privacy and vice-versa. Specific contributions include: 1) stochastic data models for both categorical and numerical data; 2) utility-privacy tradeoff regions and the encoding (sanization) schemes achieving them for both classes and their practical relevance; and 3) modeling of prior knowledge at the user and/or data source and optimal encoding schemes for both cases.
The solutions offered to-date for end-user privacy in smart meter measurements, a well-known challenge in the smart grid, have been tied to specific technologies such as batteries or assumptions on ...data usage without quantifying the loss of benefit (utility) that results from any such approach. Using tools from information theory and a hidden Markov model for the measurements, a new framework is presented that abstracts both the privacy and the utility requirements of smart meter data. This leads to a novel privacy-utility tradeoff problem with minimal assumptions that is tractable. For a stationary Gaussian model of the electricity load, it is shown that for a desired mean-square distortion (utility) measure between the measured and revealed data, the optimal privacy-preserving solution: i) exploits the presence of high-power but less private appliance spectra as implicit distortion noise, and ii) filters out frequency components with lower power relative to a distortion threshold; this approach encompasses many previously proposed approaches to smart meter privacy.
Certificateless-based signcryption overcomes inherent shortcomings in traditional Public Key Infrastructure (PKI) and Key Escrow problem. It imparts efficient methods to design PKIs with public ...verifiability and cipher text authenticity with minimum dependency. As a classic primitive in public key cryptography, signcryption performs validity of cipher text without decryption by combining authentication, confidentiality, public verifiability and cipher text authenticity much more efficiently than the traditional approach. In this paper, we first define a security model for certificateless-based signcryption called, Complex Conjugate Differential Integrated Factor (CC-DIF) scheme by introducing complex conjugates through introduction of the security parameter and improving secured message distribution rate. However, both partial private key and secret value changes with respect to time. To overcome this weakness, a new certificateless-based signcryption scheme is proposed by setting the private key through Differential (Diff) Equation using an Integration Factor (DiffEIF), minimizing computational cost and communication overhead. The scheme is therefore said to be proven secure (i.e. improving the secured message distributing rate) against certificateless access control and signcryption-based scheme. In addition, compared with the three other existing schemes, the CC-DIF scheme has the least computational cost and communication overhead for secured message communication in mobile network.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
► We model a manufacturer selling many products to two retailers. ► Consumers choose between retailers based on price, variety, search cost. ► High retailer differentiation hurts retailers and ...manufacturer. ► When market is fully covered, channel is coordinated with a wholesale price contract. ► Retailer cost hurts manufacturer more as retailer absorbs the cost.
Manufacturers typically sell consumer products through retailers and the presence of intermediaries has interesting ramifications for their product variety and pricing decisions. Retailers may want higher variety to help reduce price competition but the costs of variety are borne by the manufacturer. The increased variety may increase demand and profits for the manufacturer too but this depends on market-specific factors as well as costs. We explore these interactions through a model wherein a manufacturer sells multiple product variants at a wholesale price to two retailers who in turn compete for consumers. Consumers choose between the retailers based on the price and variety offered by each retailer and the search or transportation cost incurred by the consumer, equivalent to the level of retailer differentiation in our model. Several insights emerge from the analysis. The manufacturer offers the same variety to both retailers and this variety increases with market size and consumer sensitivity to variety. We find that some retailer differentiation benefits the retailers (not the manufacturer) but too much differentiation hurts both the retailers and the manufacturer. If the market is fully covered, then the channel is coordinated even with a simple wholesale pricing contract. If the retailers incur costs to sell the product, the manufacturer surprisingly loses out more than the retailers and in fact absorbs some or all of the retailer costs. Finally, asymmetry between retailers has some unexpected consequences. For example, variety is not impacted by asymmetry in consumer preferences for a retailer and the manufacturer offers the same variety to both retailers.
In this paper, we study the standardization and customization decisions of two firms in a competitive setting, along with variety, lead time, and price decisions. We incorporate consumer ...heterogeneity both in firm preference (or store convenience) and in product attribute preferences. We find that the equilibrium outcome depends on the cost efficiencies of the production technologies as well as the consumer sensitivity to product fit and lead time. We develop an index that signifies the relative attractiveness of the standardization and customization strategies, and the potential outcomes. We identify the strategic roles of product variety and lead time in the competition. In contrast to the previous literature, we find that increasing the variety will not intensify the price competition if there is sufficient firm differentiation. Rather, it relieves the price pressure for the firm as it satisfies consumer needs better and enables higher price premiums. We also analyze the impact of asymmetric variable costs, fixed costs, and brand reputation on the equilibrium decisions.
Owing to the increasing growth in digital communication as well as the multimedia applications, security has now become a very significant problem in the communication as well as storage space of ...such images. The Visual Cryptography (VC) has been used for hiding the information that are in the images which is a special technique of encryption that is decrypted by a human visual system. In this paper, a technique for embedding a secret message within that of a cover-image to ensure the interceptors will not observe the presence of such hidden data is presented. The method has an essential conception by means of a simple Least Significant Bit (LSB) substitution. Being inspired by the steganography approach, the current work splits the cover images into n blocks of 8X 8 pixels and into a secret message of n partitions in order to improve the image quality and to increase the capacity of secret message along with its security level. For the purpose of improving this stego-image quality and for increasing the capacity of secret message along with its security level, being inspired by the current work that splits cover images into the n blocks of 8X 8 pixels and into a secret message of n partitions. In the proposed method, the Cuckoo Search (CS) is used for searching an approximate and optimal solution of finding any optimal substitution matrix to transform the message in every block as opposed to finding a single optimal matrix for substitution and the entire cover-image is presented. The final quality of its resulting in the stego-image, and its secret message and its capacity with the level of security of this method proposed will be calculated and then comparted to the other different methods. The results of the experiment proved that the proposed method outperformed all the Joint Photographic Experts Group (the JPEG) and the Joint Quantization Table Modification (the JQTM) based method in terms of quality of image, security level and embedding capacity.
Quantifying security risk is an important and yet difficult task in enterprise network security management. While metrics exist for individual software vulnerabilities, there is currently no standard ...way of aggregating such metrics. We present a model that can be used to aggregate vulnerability metrics in an enterprise network, producing quantitative metrics that measure the likelihood breaches can occur within a given network configuration. A clear semantic model for this aggregation is an important first step toward a comprehensive network security metric model. We utilize existing work in attack graphs and apply probabilistic reasoning to produce an aggregation that has clear semantics and sound computation. We ensure that shared dependencies between attack paths have a proportional effect on the final calculation. We correctly reason over cycles, ensuring that privileges are evaluated without any self-referencing effect. We introduce additional modeling artifacts in our probabilistic graphical model to capture and account for hidden correlations among exploit steps. The paper shows that a clear semantic model for aggregation is critical in interpreting the results, calibrating the metric model, and explaining insights gained from empirical evaluation. Our approach has been rigorously evaluated using a number of network models, as well as data from production systems.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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