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.
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.
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.
6967475
Protocol System Integration, Interface and Interoperability
Heterogeneous network protocol systems are integrated together to fulfill complex tasks and their interoperability is a major hurdle for the network reliability and quality of services. We identify a new equivalence relation of states that preserves the integrated system interface behaviors. Based on this state equivalence we study the minimization of the system components with respect to their interfaces and design an efficient polynomial time minimization algorithm. We apply our technique to GMPLS protocols and obtain a significant state space reduction. We discuss integrated protocol system verification and interoperability testing with the minimized state system without resorting to the global state space information.
33611736
RAGOBOT: A New Platform for Wireless Mobile Sensor Networks
We present Ragobot, a fully-featured validated platform for use in mobile sensor networks. Ragobot is a robot of small dimensions with features that surpass those provided by many other robots in this category. Ragobot hardware and software are implemented with modularity as one of the main considerations; therefore, these are easy to upgrade and customize according to the needs of each specific application. Moreover, we present Ragoworld, a controlled physical space for the development and evaluation of mobile sensor network algorithms.
7389460
Fault Detection of Hierarchical Networks with Probabilistic Testing Algorithms
As communications networks are expanding to larger areas the control and maintenance of routing information are becoming a formidable task. To cope with its size and complexity and to make the network reliable and scalable hierarchical network has been proposed with new features to support the information infrastructure. However, the network hierarchy adds more complications to the network design and implementations and that hampers the network reliability and quality of services. Conformance testing is known to be a powerful tool for network fault detection yet most of the works in the published literature are on networks without hierarchy. We present probabilistic algorithms for testing hierarchical networks along with the added features. Based on a formal model of the networks, we provide a formal analysis that shows that our probabilistic algorithms guarantee a high fault coverage with a feasible number of tests. To further reduce the number of tests we identify test equivalence classes and that enables us to significantly reduce the number of tests yet without losing the fault coverage. Experimental results on Internet OSPF protocol are reported.
41830429
An Optimal Algorithm for Roundness Determination on Convex Polygons
Abstract In tolerancing, the Out-Of-Roundness factor determines the relative circularity of planar shapes. The measurement of concern in this work is the Minimum Radial Separation, as recommended by the American National Standards Institute (ANSI). Here we show that the algorithm given in Le and Lee [6] runs in θ ( n 2 ) time even for convex polygons. Furthermore, we present an optimal O ( n ) time algorithm to compute the Minimum Radial Separation of convex polygons, which represents not only a factor n improvement over the previously best known algorithm, but also a factor of log n improvement over Le and Lee's conjectured complexity for the problem.
14664253
A Bit-Width Optimization Methodology for Polynomial-Based Function Evaluation
We present an automated bit-width optimization methodology for polynomial-based hardware function evaluation. Due to the analytical nature of the approach, overflow protection and precision accurate to one unit in the last place (ulp) can be guaranteed. A range analysis technique based on computing the root of the derivative of a signal is utilized to determine the minimal number of integer bits. Fractional bit requirements are established using an analytical error expression derived from the functions that occur along the data path. Global fractional bit optimization across multiple computation stages is performed using simulated annealing and circuit area estimation functions