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Advanced Information Networking and Applications, 2004. AINA 2004. 18th International Conference on

Date 29-31 March 2004

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  • Multi-path transmission based on overlay network

    Page(s): 330 - 333 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2247 KB) |  | HTML iconHTML  

    We present a throughput enhanced transport approach, multipath overlay transmission (MPOT), which builds an overlay network on top of the IP underlying network, and transmits different data parts via different overlay paths. This multipath transmission approach in overlay network can keep away from the bottleneck link, and increase the throughput with multiple overlay paths. We also introduce the pipeline buffering and dynamic path switching to improve the performance of MPOT. The performance of the MPOT scheme is verified and compared to the standard single-path IP transmission using ns simulations. It is shown that MPOT scheme greatly outperforms standard single-path IP transmission for file transfer and real-time media transport when some bottleneck links are located in the IP single-path. View full abstract»

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  • A packet scheduling scheme for broadband wireless networks with heterogeneous services

    Page(s): 355 - 358 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (261 KB) |  | HTML iconHTML  

    A frame-based packet scheduling scheme, the pinwheel scheduling (PWS) scheme, is proposed and investigated at the medium access control (MAC) layer in broadband wireless networks. The objective of the proposed scheduling scheme is to provide, respectively, low delay and low jitter for real-time traffic and short queue length for nonreal-time traffic. We have demonstrated in this paper that the proposed PWS scheme not only satisfies the packet-level QoS requirements but also has low implementation cost. As the number of constant bit rate (CBR) connections increases, variable bit rate (VBR) traffic would suffer a larger jitter, the PWS with modular strategy (PWS/MS) scheme is proposed to further enhance the PWS scheme. We also introduce two different slot-reuse strategies named real-time traffic first (RTF) and longest queue first (LQF), respectively, to improve the resource utilization. In order to demonstrate the performance of the PWS and PWS/MS schemes, comparisons are made with existing schemes such as the round-robin (RR) and weighted-round-robin (WRR) by using the OPNET software. Simulation results show that the proposed schemes are capable of maintaining the lowest delay and jitter for VBR and CBR traffic while not sacrificing the available bit rate (ABR) traffic. View full abstract»

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  • Can streaming of stored playback video be supported on peer to peer infrastructure?

    Page(s): 200 - 203 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (321 KB) |  | HTML iconHTML  

    Streaming live video over peers in the Internet is gaining popularity since it has the advantage of reducing the load on the server and enable the server to perform other specialized services more effectively. It also helps reduce the server bandwidth and is therefore no more a limiting factor for the number of clients served. We propose a architecture for 'streaming stored video' over peer-to-peer network. While a given peer continues to receive segments of the stream, simultaneously caching these segments locally renders this peer to inturn act as a source for other peers. These peers are highly transient in nature and the exit of a peer from the network results in loss of video segments. We overcome this in our architecture by exploiting the inherent redundancy of FEC encoding of video streams. Through simulations we establish the novelty of our architecture and show that our proposed solution incurs minimum overhead on the peers and does not increase the playback latency much more than the jitter buffer latency. View full abstract»

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  • Recovery protocol for dynamic network reconstruction on disaster information system

    Page(s): 87 - 90 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (715 KB) |  | HTML iconHTML  

    So far, we have developed effective wide area disaster information network (WDN) using Internet over the combination of both wired and wireless network. In this information network, two important functions including resident safety information system and bidirectional video communication system between evacuation places and disaster information center are provided. However, in this WDM, system failure of network and computing facilities by disaster was not considered. In order to recover the information system as soon as possible from the system failure, network protocol has to deal with those requirements. We introduce Wireless Recovery Protocol (WRP) to temporally recover WDM with minimum configuration as soon as possible even though some of network and computing facilities were damaged by disaster, using network management and GPS functions. The design and implementation of the WRP is precisely described. The prototype system and its hardware and software environment to evaluate its functionality are also precisely described. View full abstract»

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  • An identity-based ring signature scheme from bilinear pairings

    Page(s): 182 - 185 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (224 KB) |  | HTML iconHTML  

    At the conference Asiacrypt 2001, Rivest, Shamir and Tauman firstly addressed the concept of ring signature. We propose an identity-based ring signature scheme from bilinear pairings. As compared with the Zhang-Kim scheme (presented at the conference Asiacrypt 2002), our scheme is more efficient in computation and requires fewer pairing operations. View full abstract»

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  • Evaluation of multi-agent model for community formation in network society

    Page(s): 131 - 136 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (346 KB) |  | HTML iconHTML  

    Advances in information technology are changing the social environment, and have brought about the so-called information-oriented network society. One of the major issues in the network society is how to bring people together, that is how to form the communities that share similar interests. The formation of communities brings a great deal of benefits to the members such as social collaboration on the Internet, recommendations from people who are interested in similar topics, etc. However, acquiring information about communities and selecting appropriate communities to join is a burden for most of the people and the burden restricts their lives in the network society. We propose a model of community formation with multi-agents with consideration of the cognitive balance model of the user. Personal agents can help the users by gathering and exchanging information, and recommending or assisting the users in making choices. The proposed model is evaluated through experiments. View full abstract»

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  • A class-based allocation mechanism for delay sensitive traffic in WLANs

    Page(s): 393 - 396 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (262 KB) |  | HTML iconHTML  

    HIPERLAN/2 is a recent standard from ETSI for highspeed wireless LANs. This work explores this standard when providing QoS support to different traffic types. We describe a new bandwidth allocation protocol, which distinguishes among five types of connections, each one of them having its own QoS requirements. We carry out a performance evaluation via simulations that reflects the behavior of the novel MAC protocol. The bandwidth allocation protocol is evaluated in terms of its flexibility and efficiency in supporting delay sensitive traffic. We look particularly to MPEG-4 video communications, an application which is expected to be widely deployed in broadband wireless LANs. View full abstract»

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  • An adaptive medium access control protocol for robot inter-communication in autonomous distributed systems

    Page(s): 545 - 550 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (253 KB) |  | HTML iconHTML  

    In autonomous distributed robot systems many robots cooperate together to carry out many difficult tasks that single robots can not realize. But, in order to cooperate together the robots should communicate with each other. Therefore, the inter-communication among robots is very important problem to be solved. We propose an adaptive reservation-time division multiple access (AR-TDMA) medium access control protocol which can realize a real-time communication among robots in a heterogeneous environment by using a reservation mechanism. Also, by using an adaptive time slot allocation method, the protocol has a flexible behavior and can deal with the changes of number of robots. Furthermore, the proposed protocol can reduce the packet collision probability. View full abstract»

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  • A next generation knowledge management system architecture

    Page(s): 191 - 195 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (390 KB) |  | HTML iconHTML  

    The explosive growth in online information is making it harder for large, globally distributed organizations to foster collaboration and leverage their intellectual assets. Recently, there has been a growing interest in the development of next generation knowledge management systems focussing on the artificial intelligence based technologies. We propose a generic knowledge management system architecture based on ADIPS (agent-based distributed information processing system) framework. This contributes to the stream of research on intelligent KM system to supports the creation, acquisition, management, and sharing of information that is widely distributed over a network system. It will benefit the users through the automatic provision of timely and relevant information with minimal effort to search for that information. Ontologies which stand out as a keystone of new generation of multiagent information systems, are used for the purpose of structuring the resources. This framework provides personalized information delivery, identifies items of interest to user proactively and enables unwavering management of distributed intellectual assets. View full abstract»

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  • Region-based stage construction protocol for fault tolerant execution of mobile agent

    Page(s): 499 - 502 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (473 KB) |  | HTML iconHTML  

    Fault tolerance is essential to the development of reliable mobile agent systems in order to guarantee continuous execution of mobile agents. For this purpose, previous work has proposed fault tolerant protocols for mobile agent execution based on stage construction. However, when previous protocols are applied to a multiregion mobile agent computing environment, the overhead of work such as monitoring, election, voting and agreement is increased. We propose a region-based stage construction (RBSC) protocol for fault tolerant execution of mobile agents in a multiregion mobile agent computing environment. The RBSC protocol uses new concepts of quasiparticipant and substage in order to put together some places located in different regions within a stage in the same region. Therefore, the RBSC protocol decreases the overhead of stage works. Consequently, the RBSC protocol decreases the total execution time of mobile agents. View full abstract»

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  • Access control by using object properties and categorized methods

    Page(s): 397 - 402 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (336 KB) |  | HTML iconHTML  

    We propose an access control model that is suitable for a distributed object oriented environment. Our model has two features: authentication with object properties and method categorization by a security level. The object property is meta information of a client, and the client is vested with it in advance. To use the object properties, a server can identify a huge number of clients in the environment by groups that is categorized with the object properties of the clients. And also, to use a combination of multiple object properties in authentication, an administrator of the server can determine the flexible range of target clients. The security level shows how much impact the method affects server's data. If a designer of the server categorizes the server's methods with a security level, an administrator of the server can set an authorization rule to each category instead of each server's method. The categories constitute a tree structure, since a parent category includes child categories. As a result of this, the administrator can set an authorization rule easier than authorization without categorization by the security level. Furthermore, we implemented above the access control model and we evaluated their efficiency. View full abstract»

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  • WKeeper: a distributed Web filtering system for IPv6 home networks

    Page(s): 471 - 474 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (413 KB) |  | HTML iconHTML  

    We propose a distributed architecture of Web filtering system focused on its operation and implementation for IPv6 home networks. The realized system, called WKeeper, employs the feature of IPv6 anycast to achieve distributed load balance. WKeeper has been proven to be functioning well in both IPv4 and IPv6 networks even with mobility support. In a home network environment, WKeeper efficiently and precisely maintains the URL-block-list database with enormous amount of entries, as well as its operation is robust and with low cost. Besides, experimental result shows that the delay of query response is bounded significantly even if heavy load. View full abstract»

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  • Using RDF/RDFS to support visualized online authoring tool for teachers

    Page(s): 124 - 129 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (551 KB) |  | HTML iconHTML  

    The purpose of this study is to implement visualized online authoring tool (VOAT) by using RDF/RDFS for teachers at primary and junior high school levels in Taiwan to author their teaching materials. Based on the content repository management system (CRMS), this study addresses the interoperability problem consequence of the proliferation of online learning systems, mainly in Internet environments, which is considered by key standardization institutions such as ADL's SCORM specifications. Using mathematics ontologies by RDF/RDFS in this study gives teachers a more intuitive choice of mathematics of the modeling primitives and richer ways to define mathematics concepts and attributes. RDF/RDFS introduces basic ontological modeling primitives into the Web. The result of this study is demostrated by a scenario that selected to explain how teachers authoring a mathematics course on VOAT. Finally, the implications for future research are also proposed. View full abstract»

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  • Distance based location management in cellular PCS network ? a critical study

    Page(s): 95 - 98 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (324 KB) |  | HTML iconHTML  

    A distance-based approach is an efficient strategy for location management of mobile hosts in a cellular PCN. But what is the optimum distance for distance-based location management? Does it depend on cell-size, and/or the movement behavior of an individual user, depending on her movement pattern, more efficient? Or should a simple fixed distance for all users be adopted? We have shown that a fixed distance of 4 is nearly optimum for all the mobile hosts, irrespective of a range of variation of their mobility behavior, and the cell size of the network. A more efficient adaptive distance algorithm, where distance is changed according to mobility behavior, is proposed. View full abstract»

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  • Distributed replication and caching: a mechanism for architecting responsive Web services

    Page(s): 289 - 292 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (253 KB) |  | HTML iconHTML  

    The focus is on the mechanism that supports the provision of the adequate service level by relying on Web system architecture with multinode clustering. Replication of Web documents can improve both performance and reliability of the Web service. Server selection algorithms allow Web clients to select one of the replicated servers which is "close " to them and thereby minimize the response time of the Web service. View full abstract»

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  • Maximum likelihood estimation of integer frequency offset for OFDM

    Page(s): 223 - 226 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (256 KB) |  | HTML iconHTML  

    One of the principal disadvantages of orthogonal frequency division multiplexing (OFDM) is very sensitive to frequency offset. Carrier frequency offset can be divided into two parts: an integer one and a fractional one. The integer frequency offset has no effect on the orthogonality among the subcarriers, however causes a circular shift of the received data symbols, resulting in a BER of 0.5. The maximum likelihood (ML) estimation algorithm of the integer frequency offset is derived under the assumption that the channel impairments only consist of additive noise. Simulation results show that it can perform well even in a time-dispersive channel. Its performance is assessed and compared with the conventional method by computer simulations for the additive white Gaussian noise (AWGN) channel and a multipath fading channel. View full abstract»

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  • Development and evaluation of a minutes system focusing on importance in a meeting

    Page(s): 293 - 298 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (608 KB) |  | HTML iconHTML  

    At meetings, a variety of outputs such as presentation materials, text minutes, video/audio data are generated. Both meeting participants and absentees can easily understand meeting minutes easily if these data are mutually referred and extracted important points. Therefore, focusing on participants' importance, we have proposed and developed the system that automatically produces Web pages by collecting and editing meeting data with much labor saving so as to easily understand a sequence of meeting. The importances submitted by participants are automatically collected and showed their status to participants in this system. We developed, first, prototype version 1 and then enhanced to version 2 by taking into consideration of evaluation results obtained from user feedbacks. Finally, we state evaluation results of new version, and show the validity of our developed system. View full abstract»

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  • Design and implementation of a SIP-based VoIP architecture

    Page(s): 187 - 190 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (236 KB) |  | HTML iconHTML  

    The emergence of the session initiation protocol (SIP) promises simple and efficient handling of multimedia sessions among multiple users. We present the design and implementation of a VoIP system based on SIP. Our SIP-based VoIP system provides a wide range of services multipoint call, multiple audio encoding formats, and complex functionalities such as call muting and call-hold facilities, and personal mobility support. View full abstract»

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  • Development of a test pattern for measurement of color visual MTF properties

    Page(s): 2 - 5 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (226 KB) |  | HTML iconHTML  

    Human visual color MTF (modulation transfer function) properties were measured using special color grating patterns. These patterns printed on paper were based on patterns shown on a computer display. In this work, printed pattern on a paper was developed and measurement using the test patterns was implemented. These test patterns are available for the measurement of the human visual color properties. View full abstract»

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  • Multicast routing representation in ad hoc networks using fuzzy Petri nets

    Page(s): 420 - 423 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (335 KB) |  | HTML iconHTML  

    In an ad hoc network, each mobile node plays the role of a router and relays packets to final destinations. The network topology of an ad hoc network changes frequently and unpredictable, so that the routing and multicast become extremely challenging. We describe the multicast routing representation using fuzzy Petri net model with the concept of immediately reachable set in wireless ad hoc networks which all nodes equipped with GPS unit. It allows structured representation of network topology, and has a fuzzy reasoning algorithm for finding multicast tree and improves the efficiency of the ad hoc network routing scheme. Therefore when a packet is to be multicast to a group by a multicast source, a heuristic algorithm is used to compute the multicast tree based on the local network topology with a multicast source. Finally, the simulation shows that the percentage of the improvement is more than 15% when compared the IRS method with the original method. View full abstract»

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  • A sensor-actuator map for organization of position sensor feedback control for multiple links structure/wire driven system

    Page(s): 551 - 554 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (410 KB) |  | HTML iconHTML  

    Multiple links structure/wire driven (tendon) system is one of robot structures, that has a serial-link structure driven by a wire-drive mechanism. It can be applied to a manipulator like elephant's trunk, a moray arm, the backbone of a humanoid, etc.. However, transformations among coordinates (task-oriented, joint-angles and wire-length) are very complicated. Therefore, it is not clear how sensory feedback control laws should be realized for the system. We propose a sensor-actuator map in which the sensor coordinates and actuator coordinates are arranged. By finding the paths from the sensor coordinates to the actuator coordinates on the map, the sensory feedback control laws can be built. View full abstract»

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  • Functional networks based Internet end-to-end delay dynamics

    Page(s): 540 - 543 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (326 KB) |  | HTML iconHTML  

    Nonstationarity and nonlinearity are found by the analysis of various delay series measured from different Internet links. The fact that different types of links have different degrees of self-similarity is also obtained. By constructing appropriate network architecture and neural functions, functional networks can be used to model the Internet end-to-end nonlinear delay time series. Furthermore, by using adaptive parameter studying algorithm, the nonstationarity can also be well modeled. The numerical results show that the provided functional network architecture and adaptive algorithm can precisely characterize the Internet end-to-end delay dynamics. View full abstract»

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  • Mobile agents as smart virtual counterparts

    Page(s): 270 - 273 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (319 KB) |  | HTML iconHTML  

    Smart spaces should not be bound by physical constraints but should transcend them in order to provide enhanced services. One way of overcoming this is by having smart virtual counterparts represent the real world entities in smart spaces. We propose that mobile agent technology is aptly suited for providing smart virtual counterparts of real-world entities in the virtual world and can be used to enhance the performance of smart spaces. We also present a prototype implementation using the Grasshopper mobile agent toolkit as proof of concept. View full abstract»

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  • Multistory annotation system: a novel application of distance learning

    Page(s): 116 - 119 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (334 KB) |  | HTML iconHTML  

    For effectively browsing and navigation, the semantic annotation is essential for the visual content of movies. It is very important to show the particular object that the movie producer wants to highlight in educational videos or commercials. We propose an interactive and structure-based video annotation system, in which we can describe the video object and make multistory movies. The system provides a manual object-based interface for film producers to select the meaningful object and annotate it. We also provide a video story constructing function to interact with the audience. View full abstract»

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  • Dynamic reconfiguration of telecom services architectures according to mobility and traffic models

    Page(s): 447 - 450 Vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (237 KB) |  | HTML iconHTML  

    Radio multimedia services are constantly evolving. Service providers and operators must follow this evolution to address customers' expectations. With customers' changeable behaviors, a platform must review its architecture and adapt itself to reduce time-to-market of new services and satisfy all demands. In this context, solutions are about auto-adaptation and reconfiguration. These two operations should take place dynamically and rapidly, with no damage to platform functions. They also have to fulfill other features such as security, real time applications, error tolerance, etc. Our aim is to give an architecture which can support the reconfiguration process. We also expose some situations and scenarios to prove that bad situations (low throughput, call drop, bad QoS, etc.) are improved with reconfiguration. View full abstract»

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