Multimedia streaming and video on demand (VoD) services are among those hottest applications over the Internet. Traditional client/server pattern is stumbled due to the lack of scalability and limitation of service ca...
详细信息
ISBN:
(纸本)0780393112
Multimedia streaming and video on demand (VoD) services are among those hottest applications over the Internet. Traditional client/server pattern is stumbled due to the lack of scalability and limitation of service capacity. Peer-to-Peer paradigm has been introduced to solve these issues. The key idea is that peers not only receive multimedia stream but also serve multimedia data to others. In this paper, we present a novel scheme that builds a multimedia streaming and caching service on a distributed hash table (DHT) based overlay. We adopt DHT to establish a decentralized caching service. The location information of cached segments is distributed among different peers and the information about segments from the same video is organized into an application-level multicast group. We also propose a cache replace algorithm on each peer. In our simulation, our design achieves good scalability with a low service reject rate. Besides, good load balance is also achieved as well as desired quality-of-service.
In this paper we present GPE4CGSP, which targets the interoperability between GPE (grid Programming Environment) and CGSP (Chinagrid Support Platform). The web services technique and gridftp data transfer protocol are...
详细信息
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...
详细信息
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.
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...
详细信息
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.
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...
详细信息
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...
详细信息
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,...
详细信息
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.
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...
详细信息
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.
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,...
详细信息
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...
详细信息
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.
暂无评论