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.
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.
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.
Automated trust negotiation (ATN) is an important means to establish trust between strangers through the exchange of digital credentials and mobile access control policies specifying what combinations of credentials a...
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Automated trust negotiation (ATN) is an important means to establish trust between strangers through the exchange of digital credentials and mobile access control policies specifying what combinations of credentials a stranger must submit. While ATN provides a good mechanism to share resources in the open and distributed environments, there still exist some pitfalls. A notable problem is that the negotiation process is easy to be interrupted, which leads the negotiation to failure. Thereto, current protection techniques are somehow complex and heavyweight, which greatly limits ATN's applications. To solve these problems, an Email Based ATN Model (EBAM) is proposed. A credential template and an access control policy template are specified to carry information. All the transmitted messages are encrypted by private keys. The data exchange is realized through the negotiators' emails. A use case is given to show how it works, which proves the model sound and reasonable.
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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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 problem and the relatively more efficient one is using ontology. Based on this method, we focus on alleviating semantic inconsistency of various platforms and designing a novel ontology. This ontology is depicted by resource description framework (RDF) and transacted by adapters. Finally, we test our method and analyze its performance.
With the increasing scale of data transmitted over Internet, how to effectively query and present mass distributed monitoring data has become a serious problem in distributed monitoring field. Almost all users want to...
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ISBN:
(纸本)9781424413737;1424413737
With the increasing scale of data transmitted over Internet, how to effectively query and present mass distributed monitoring data has become a serious problem in distributed monitoring field. Almost all users want to retrieve data as detail as possible; on the other hand, the practical bandwidth and latency limit the data scale in transmission. In order to solve this conflict, we design a flexible two-level mechanism. In our platform with this mechanism, users can customize various retrieving spaces by submitting their clients' memories. Subsequently, after receiving some request of observing the performance of monitored nodes, the server-end will process the data queried from database according to some rules before responding clients with two-level monitoring data streams (compressed data level and original data level). Through carefully testing, we testify this mechanism is indeed valuable in querying and presenting large-scale monitoring data.
It is still a challenging task to provide large scale video-on-demand (VoD) streaming services based on overlay network due to its inherent dynamicity and heterogeneity. Most of previous work has focused on how to con...
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It is still a challenging task to provide large scale video-on-demand (VoD) streaming services based on overlay network due to its inherent dynamicity and heterogeneity. Most of previous work has focused on how to construct a structured overlay to tackle this issue, i.e., tree-based overlay and DHT. However, they always suffer from inefficient resource utilization and poor reliability. In this paper, we propose a new solution based on unstructured overlay, called gridCast, in which a directional gossip protocol and a score-based partner selection algorithm are designed to explore multiple data suppliers for each joined peer. In this way, gridCast can make efficient use of the available upload bandwidth of peers to achieve better scalability and reliability. The experimental results from our early deployment show that it is feasible to provide scalable VoD services based on unstructured overlay.
Peer-to-Peer (P2P) networks have been shown to be a promising approach to provide large-scale Video on Demand (VoD) services over Internet for its potential high scalability. However, for a normal peer,how to efficien...
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Peer-to-Peer (P2P) networks have been shown to be a promising approach to provide large-scale Video on Demand (VoD) services over Internet for its potential high scalability. However, for a normal peer,how to efficiently schedule media data to multiple asynchronous peers for VoD services in such networks remains a major challenge. Hereby we propose a hybrid scheduling scheme for data dissemination in P2P VoD system in this paper, called OCTOPUS,which is combined with adaptive scheduling scheme at normal time and special scheduling strategy emergently. Usually each peer is given a value,meaning scheduling bandwidth to represent service capacity, which is an integrated evaluation for peer's bandwidth and services ability, also including statistical characteristics about historical data transferring. According to the value, one peer can adjust the expectation of each neighbor's abilities and send scheduling request of media data to all *** case of failure scheduling, emergent scheduling scheme will be called and limited data requests will be sent to media servers. OCTOPUS scheme helps to make sufficient utilization of end-peers' resource,alleviate the load of source server and improve their scalability. Experimental result from a P2P VoD system, gridCast, based on OCTOPUS schemes,shows that OCTOPUS achieves obvious effect.
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