Catálogo de publicaciones - libros

The existing protocol defined in the ISO/IEC 18000-3 standard does not include the cryptographic authentication mechanism. To remove security vulnerabilities, this paper proposes a strong authentication protocol for RFID tag using SHA-1 hash algorithm. The protocol is based on a three-way challenge response authentication protocol between the tags and a back-end server. In addition, three types of the protocol packets are extended for realizing a strong authentication mechanism, which modifies the protocol defined in the ISO/IEC standard.

In order to verify the proposed scheme, a digital Codec is described in Verilog HDL, and simulated using extended three packets as input vectors. The system operates at a clock frequency of 75 MHz on Xilinx FPGA device. From comparison and implementation results, we will show that our scheme is a well-designed strong protocol that satisfies various security requirements in RFID system environment.

In ubiquitous environments, users of multimedia service can access to rich multimedia content any time any where, via user-friendly and easy-to-carry handheld, mobile and wearable devices such as mobile phones, PDAs, laptops and even vehicles. Besides the usual requirement of ensuring the integrity and privacy of these contents as they travel from one device to the next, there is also a need for optimal bandwidth use of these devices to ensure the user’s comfort in hassle-free access.

schemes is one measure used to ensure integrity of content, typically images. Fragile watermarking schemes commonly exploit particular properties of transmitted images and thus provide and features not found in image authentication schemes based on purely cryptographic techniques. The basic idea in an image authentication scheme is to compute and insert an authentication mark into the image, and later during verification to recompute the same mark and compare with the inserted version for a match.

In the context of the optimal bandwidth ubiquitous environment, we formulate the notion of the to his multimedia content. We then propose a fragile watermarking scheme that achieves this notion, thereby making optimal use of the bandwidth. This scheme also prevents two problems that we highlight on a previous fragile scheme by Byun et al. As an aside, our results appear to be the first analysis of the Byun et al. scheme. Furthermore our proposed scheme is one of the only three known SVD-based fragile watermarking schemes to date, and the only one that protects the originator’s rights.

Authentication is the most important issue to control the home networks remotely. In this paper, a strong authentication and key agreement method for a smart home network system is presented. The proposed scheme uses a smart card which stores private information and performs cryptic operations. It also uses a modified 3GPP security system that is suitable for the home network. Our scheme provides not only security features which S/KEY variants schemes have but also new features that they do not have.

Ubiquitous computing environment must provide users with seamless anytime and anywhere access to services. However, the ubiquitous computing environment contains many weaknesses in security, and creates many problems for user’s anonymity and privacy. Therefore, we proposed a novel ticket-based AAA(Authentication, Authorization, Accounting) mechanism for ubiquitous environment. The AAA mechanism is information security technology that systematically provides authentication, authorization and accounting functions, not only in the existing wire network but also in the rapidly developing ubiquitous network, with various ubiquitous services and protocol. Currently, IETF(Internet Engineering Task Force) AAA Working Group deals with about secure AAA protocol in ubiquitous network and studies methods that offer secure authentication through mobility of Mobile Nodes. Therefore, in this paper, the AAAH(Home Authentication Server) authenticates the Mobile device. After that, it uses a ticket issued from AAAH, even if the device moves to a foreign network, and can provide service in foreign network without accessing by AAAH. We also present a mechanism that can offer user privacy and anonymity. This proposed mechanism can reduce the signal and reduce the delay of message exchanged using tickets, can offer persistent service and heightened security and efficiency.

Localization using wireless signal is a hot field now, and the real time indoor localization is a difficult problem for its complex and sensitive to the environment. This paper proposes a method based on grid to convert global to local. Based on the Markov random field, we convert efficiently signals between different environments and achieve high precision and fast speed. The paper also discusses influence of multiple signals to location precision, explains that multiple sets of signal can be used greatly to improve localization precision. To reduce the number of supervised grids in learning data required by the grid-matching algorithm, this paper presents a method which combines the grid matching and the signal strength model. First the position is localized by the grid-matching method and then its location is refined by using the signal strength model in the local area.

The H.264/AVC provides gains in compression efficiency of up to 50% over a wide range of bit rates and video resolutions compared to previous standards. However, these features incur a considerable increase in encoder complexity, mainly because of mode decision. In this paper, we propose an efficient method of fast Inter-skip mode selection algorithm for inter frame coding in H.264/AVC. Firstly, we select skip mode or inter mode by considering the temporal correlation. Secondly, we select variable block size on inter mode by considering the spatial correlation. Simulations show that the proposed method reduces the encoding time by 64% on average without any significant PSNR losses.

The objective of this study is to identify the business process for the photonics industry. This business process used the Unified Modeling Methodology (UMM) which was recommended in the ebXML specification. First, the strength of the UMM was described by comparing it with other business process modeling methodologies. Second, the overall business process of the photonics industry was analyzed. The procurement management process was modeled in detail using the UMM. For the business process analysis of the photonics industry, we visited one corporation which we called the A corporation, a member of the photonics industry and interviewed a business process designer and a procurement manager in depth. The procurement management process of the A corporation was represented by a usecase diagram, activity diagram, class diagram, and a sequence diagram according to the UMM structure. The procurement management process modeling of photonics industry using the UMM could be used as a sample for all the standard business processes for the photonics industry. It could be used for improved communication between the procurement manager and business process designer.

We apply rough set theory to obtain knowledge from the construction of a decision tree. Decision trees are widely used in machine learning. A variety of methods for making decision trees have been developed. Our algorithm, which compares the core attributes of objects and builds decision trees based on those attributes, represents a new type of tree construction. Experiments show that the new algorithm can help to extract more meaningful and accurate rules than other algorithms.

Due to rapid technological innovation and global competitiveness, the component cost, the selling price and the demand rate of Hi-tech industries (such as computers and communication consumer’s products) usually decline significantly with time. From a practical viewpoint, there is a need to develop a replenishing policy with finite horizon when the component cost, the selling price and the demand rate are reduced simultaneously. A numerical example and sensitivity analysis are carried out to illustrate this model. Two cases are discussed in this study: Case A considers fixed replenishment interval, Case B considers varying replenishment interval. From Case A, the results show that decreasing component cost leads to smaller replenishment interval. However, decreasing sensitive parameter of demand leads to larger replenishment interval. When both the component cost and the sensitive parameter decline-rates decrease simultaneously, the replenishment interval decreases. The solutions by Case A and B are sub-optimal and optimal respectively. The net-profit percentage difference between Case A and B is 0.060% approximately, while the computational process of Case A is easier than that of Case B.

This paper considers a production-inventory system with inflation and a random life cycle. Two conditions are discussed: the first is when the product life cycle ends in the production stage and the second is when the product life cycle ends in the non-production stage. We develop a genetic algorithm to find the optimal period time and the lowest expected total cost. Numerical examples and sensitivity analyses are given to validate the results of the production model.