A series of problems arises with the emergence and fast development of grid. Among all the problems, one of them is how to smoothly connect heterogeneous grid platforms. There are a number of ways to solve this proble...
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Nowadays, Peer-to-Peer technology has been widely used in live streaming applications and many related systems are proposed. However, their single overlay design and unbalanced scheduling methods lead to some ineffici...
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ISBN:
(纸本)9781595937575
Nowadays, Peer-to-Peer technology has been widely used in live streaming applications and many related systems are proposed. However, their single overlay design and unbalanced scheduling methods lead to some inefficiency including high control overhead and bad playback experience. This paper mainly discusses how to address these certain problems. We introduce a hybrid architecture to solve the locality problem and reduce the control overhead. We also propose a scheduling method to achieve load balance. All solutions are implemented in Anysee2.
Metadata management is a key technique of data grid. This paper presents a replication and cache based metadata management system (RCMMS) to improve metadata management of Global Distributed Storage system (GDSS). Sto...
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Metadata management is a key technique of data grid. This paper presents a replication and cache based metadata management system (RCMMS) to improve metadata management of Global Distributed Storage system (GDSS). Storage Service Provider (SSP) of GDSS has dedicated buffer to cache metadata. The design, implementation and evaluation of RCMMS are discussed in this paper. RCMMS provides efficient algorithms to manage highly dynamic metadata replicas. The evaluation demonstrates that replica plus cache metadata management system outperforms existing metadata management system of GDSS.
P2P technology has been widely adopted in live streaming system for its scalability and low commercial cost. However, tree based system or mesh based system still has to face the constraint or tradeoff caused by its s...
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P2P technology has been widely adopted in live streaming system for its scalability and low commercial cost. However, tree based system or mesh based system still has to face the constraint or tradeoff caused by its solo shaped overlay construction. To address this problem, this paper introduces a tree-mesh based hybrid overlay and an optimized scheduling method. These works have been proven efficient in terms of low control overhead and better streaming experience compared with other systems. All algorithms and methods have been implemented in Anysee 2.
Peer-to-peer (P2P) technology encounters serious methodological limitations to guarantee the quality of services (QoS) of P2P networks with very few peers. In this paper, we propose multiple-access channel model (MACM...
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Peer-to-peer (P2P) technology encounters serious methodological limitations to guarantee the quality of services (QoS) of P2P networks with very few peers. In this paper, we propose multiple-access channel model (MACM) to merge different P2P networks as a whole to share their data-transfer capability. The model abstracts the interlaced data links between peers as logical data channels according to their spatial-temporal relations. The channels can be subdivided based on multiplex technology and serve different applications at same time. MACM redefines P2P data-packet structure and organizes data packets into time-related groups according to cascade-packet rule to support controllable data-projection between data pools of peers. MACM-based P2P networks can be created as virtual sub-network or virtual-peer bridging strategy so as to improve the performance of P2P networks with few peers but high priorities within Internet protocol television (IPTV) and wireless sensor network (WSN) applications.
The bandwidth bottleneck and the high rate of losing packets are the major obstacles when extending P2P live streaming system to WLAN. To tide over them, a new wireless multicast agent mechanism (WiMA) based on the IP...
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ISBN:
(纸本)9781424431779
The bandwidth bottleneck and the high rate of losing packets are the major obstacles when extending P2P live streaming system to WLAN. To tide over them, a new wireless multicast agent mechanism (WiMA) based on the IP multicast buffering schedule is proposed. Wireless multicast agent gains media data by interacting with wired neighbor peers as a common P2P node, and sends data to other wireless peers in WLAN by means of multicast pushing and multicast patching. A normal wireless peer requests data according to the strategy of "emergent ones first". Experiments show that WiMA can save bandwidth in WLAN obviously with acceptable start delay and satisfied playing continuity.
Automated trust negotiation (ATN) is an important means to establish trust between strangers through the exchange of digital credentials and access control policies specifying what credentials a stranger must submit i...
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Automated trust negotiation (ATN) is an important means to establish trust between strangers through the exchange of digital credentials and access control policies specifying what credentials a stranger must submit in the open and distributed environment. While ATN brings convenience, there are still two issues unsolved successfully: 1) to protect the transmitting message; 2) to prevent the sensitive information leakage. Hidden credential can provide high security level to protect sensitive resources, policies and credentials from being attacked. Zero-knowledge is an important means to avoid leakage and can be used to protect the user's private context and sensitive information from unauthorized inferences. If hidden credentials and zero-knowledge are well-combined and redesigned, they can jointly make ATN better. Based on these, a hidden credential based oblivious automated trust negotiation model (HBOA) is proposed in this paper. In the model, the negotiation information is carried by hidden credentials, which have the same secure level with elliptic curve. Zero-knowledge protocol is provided by Pedersen commitment scheme, which ensures that no sensitive information can be attained by authorized users. A practical example is given to prove its usability.
In this paper, we propose a scalable service scheme for secure group communication in grid. In the service scheme, a series of methods and strategies are presented, such as the initialization methods for group member,...
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In this paper, we propose a scalable service scheme for secure group communication in grid. In the service scheme, a series of methods and strategies are presented, such as the initialization methods for group member, administrative domain and virtual organization, the key distribution strategy and the rekeying strategy. In order to improve the scalability of this service scheme, the services for a group are logically divided into two hierarchical levels, which is in accordance with the characteristics of group communication in grid. In addition, in order to show the efficiency and the scalability of the service scheme, simulation experiments are done. The results show that the service scheme is efficient and scalable. Thus, the service scheme can satisfy the requirement of people in large-scale, dynamic grid environment.
Efficient search for unstructured peer-to-peer information retrieval systems is a challenging problem. This paper proposes a semantic overlay based on the small world phenomenon that facilitates efficient search for i...
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Efficient search for unstructured peer-to-peer information retrieval systems is a challenging problem. This paper proposes a semantic overlay based on the small world phenomenon that facilitates efficient search for information retrieval in unstructured P2P systems. In the semantic overlay, each node maintains a number of short-range links which are semantically similar to the node, together with a small collection of long-range links that help increase recall rate of information retrieval as well as reduce network traffic. In this paper we present how to construct and maintain a semantic small world overly, and the search strategy utilizing the above semantic overlay. Experimental results show that our model can improve performance by 150% compared to Gnutella and by up to 50% compared to the Interest-based model, a similar shortcut-based search technique
In grid environment, applications are in active competition with unknown background workloads introduced by other users. To achieve good performance, performance models are used to predict the possible status of the r...
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In grid environment, applications are in active competition with unknown background workloads introduced by other users. To achieve good performance, performance models are used to predict the possible status of the resources, and to make decisions of the selection of a performance-efficient application execution strategy. In this paper, we present a scheduling decision method that utilizes the NARX neural network based load prediction to define data mappings appropriate for dynamic resources. This method uses the information of the predicted CPU load interval and variance of future resource capabilities to obtain the CPU load decision, which can be used to guide the scheduling decision. As to the predictor used here, the NARX neural network based predictor learns the model of the system from the external input information and the system itself. It inherits the mapping capability of feed forward networks and, at the same time, captures the dynamic features of load information. In this work, our predictor shows good performance for time series prediction.
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