30142962
A study on contents distribution using electronic cash system
Electronic cash systems are used as payment tools of e-commerce. They should be equipped with independence, transferability, and dividability, which are requirements of digital rights management (DRM) servicing contents. The contents can be recognized in terms of money. Its concept applies to reprint, copy, and anonymous users. This paper shows DRM model which adopted e-cash as a result of examining requirements of e-cash and DRM. The DRM introduces the hierarchical structure, and gives anonymity to the contents or users. Lastly, several methods proposed are examined, compared and analyzed.
36921568
A Study on Key Distribution and ID Registration in the AAA System for Ubiquitous Multimedia Environments
Media environment has been rapidly changed these days. Internet provides multimedia environment and has become a part of our everyday life as a new advertisement media. Authentication methods typically involve an authentication server in the home network from the authentication server of the external network, and then the external network is notified with the authentication result in the home authentication server. This paper discusses and proposes a key distribution protocol that ca be used when the user moves the external network and to ensure secure communication with the external authentication server. As the proposed technology does not receive the reissue of authentication from the home authentication server in case moving between the external authentications servers, authentication server overload can be reduced and the home network can be made to issue the key using the registered password.
140119475
A Study on Efficient Key Distribution and Renewal in Broadcast Encryption
The method of broadcast encryption has been applied to the transmission of digital information such as multimedia, software, and paid TV on the open network. In this broadcast encryption method, only previously authorized users can gain access to digital information. When broadcast message is transmitted, authorized users can first decode the session key using the previously given private key and get digital information using this session key. This way, users retrieve a message or a session key using the key transmitted by broadcasters. For their part, broadcasters need to generate and distribute keys. Broadcasters should also carry out efficient key renewal when users subscribe or unsubscribe. This paper introduces how to generate and distribute key efficiently and how key renewal works. The proposal uses two methods: (1) the server generates keys without the consent of users by anticipating users, and; (2) the server and users generate keys by mutual agreement. The advantage of the two proposed methods is that the receiver can decode broadcast message using a secret key. Even if the key is renewed later, the user can efficiently renew using only a single set of information.
6192203
Authentication for Single/Multi Domain in Ubiquitous Computing Using Attribute Certification
The Ubiquitous computer environment is thing which invisible computer that is not shown linked mutually through network so that user may use computer always is been pervasive. Intend computing environment that can use easily as user wants and it is the smart environment that user provides context awareness that is wanting computing environment. This Ubiquitous computing contains much specially weak side in security. Masquerade attack of that crawl that is quoted to user or server among device that is around user by that discrete various computing devices exist everywhere among them become possible. Hereupon, in this paper, proposed method that has following characteristic. Present authentication model through transfer or device. Suggest two method that realize authentication through device in case of moved to method (MD: Multi Domain) and user ownself space (SD: Single Domain) that realize authentication through device in case of moved user's direct path who device differs.
15096399
A Faster One-Dimensional Topological Compaction Algorithm with Jog Insertion
Abstract. We consider the problem of one-dimensional topological compaction with jog insertions. By combining both geometric and graph-theoretic approaches we present a faster and simpler algorithm to improve over previous results. The compaction algorithm takes as input a sketch consisting of a set F of features and a set W of wires, and minimizes the horizontal width of the sketch while maintaining its routability. The algorithm consists of the following steps: constructing a horizontal constraint graph, computing all possible jog positions, computing the critical path, relocating the features, and reconstructing a new sketch homotopic to the input sketch, which is suitable for detailed routing. The algorithm runs in O(|F| ⋅ |W|) worst-case time and space, which is asymptotically optimal in the worst case. Experimental results are also presented.
19612327
Instruction level redundant number computations for fast data intensive processing in asynchronous processors
Instruction level parallelism (ILP) is strictly limited by various dependencies. In particular, data dependency is a major performance bottleneck of data intensive applications. In this paper we address acceleration of the execution of instruction codes serialized by data dependencies. We propose a new computer architecture supporting a redundant number computation at the instruction level. To design and implement the scheme, an extended data-path and additional instructions are also proposed. The architectural exploitation of instruction level redundant number computations (IL-RNC) makes it possible to eliminate carry propagations. As a result execution of instructions which are serialized due to inherent data dependencies is accelerated. Simulations have been performed with data intensive processing benchmarks and the proposed architecture shows about a 1.2-1.35 fold speedup over a conventional counterpart. The proposed architecture model can be used effectively for data intensive processing in a microprocessor, a digital signal processor and a multimedia processor.
5523767
Closed Partition Lattice and Machine Decomposition
Finite-state machines are widely used to model systems in diverse areas. Often, the modeling machines can be decomposed into smaller component machines and this decomposition can facilitate the system design, implementation and analysis. J. Hartmanis and R.E. Stearns (1966) developed an elegant algebraic theory for machine decomposition that is based on the closed-partition lattice of a machine. In this paper, we study the computation of the closed-partition lattice of finite-state machines for the application to their decomposition. We present efficient algorithms for constructing the closed-partition lattice and for machine decomposition.
17311777
Ziggurat-based hardware Gaussian random number generator
An architecture and implementation of a high performance Gaussian random number generator (GRNG) is described. The GRNG uses the Ziggurat algorithm which divides the area under the probability density function into three regions (rectangular, wedge and tail). The rejection method is then used and this amounts to determining whether a random point falls into one of the three regions. The vast majority of points lie in the rectangular region and are accepted to directly produce a random variate. For the nonrectangular regions, which occur 1.5% of the time, the exponential or logarithm functions must be computed and an iterative fixed point operation unit is used. Computation of the rectangular region is heavily pipelined and a buffering scheme is used to allow the processing of rectangular regions to continue to operate in parallel with evaluation of the wedge and tail computation. The resulting system can generate 169 million normally distributed random numbers per second on a Xilinx XC2VP3O-6 device.
2008990
Dual-Tree Fast Gauss Transforms
In previous work we presented an efficient approach to computing kernel summations which arise in many machine learning methods such as kernel density estimation. This approach, dual-tree recursion with finite-difference approximation, generalized existing methods for similar problems arising in computational physics in two ways appropriate for statistical problems: toward distribution sensitivity and general dimension, partly by avoiding series expansions. While this proved to be the fastest practical method for multivariate kernel density estimation at the optimal bandwidth, it is much less efficient at larger-than-optimal bandwidths. In this work, we explore the extent to which the dual-tree approach can be integrated with multipole-like Hermite expansions in order to achieve reasonable efficiency across all bandwidth scales, though only for low dimensionalities. In the process, we derive and demonstrate the first truly hierarchical fast Gauss transforms, effectively combining the best tools from discrete algorithms and continuous approximation theory.