A distributed processing system (DPS) contains many autonomous nodes, which contribute their own computing power. DPS is considered a unified logical structure, operating in a distributed manner;the processing tasks a...A distributed processing system (DPS) contains many autonomous nodes, which contribute their own computing power. DPS is considered a unified logical structure, operating in a distributed manner;the processing tasks are divided into fragments and assigned to various nodes for processing. That type of operation requires and involves a great deal of communication. We propose to use the decentralized approach, based on a distributed hash table, to reduce the communication overhead and remove the server unit, thus avoiding having a single point of failure in the system. This paper proposes a mathematical model and algorithms that are implemented in a dedicated experimental system. Using the decentralized approach, this study demonstrates the efficient operation of a decentralized system which results in a reduced energy emission.展开更多
The load balance is a critical issue of distributed Hash table (DHT), and the previous work shows that there exists O(logn) imbalance of load in Chord. The load distribution of Chord, Pastry, and the virtual serve...The load balance is a critical issue of distributed Hash table (DHT), and the previous work shows that there exists O(logn) imbalance of load in Chord. The load distribution of Chord, Pastry, and the virtual servers (VS) balancing scheme and deduces the closed form expressions of the probability density function (PDF) and cumulative distribution function (CDF) of the load in these DHTs is analyzes. The analysis and simulation show that the load of all these DHTs obeys the gamma distribution with similar formed parameters.展开更多
As a solution for data storage and information sharing for peer-to-peer(P2P)networks,a novel distributed hash table(DHT)structure called PChord is presented in this paper.PChord adopts a bi-directional searching mecha...As a solution for data storage and information sharing for peer-to-peer(P2P)networks,a novel distributed hash table(DHT)structure called PChord is presented in this paper.PChord adopts a bi-directional searching mechanism superior to Chord and enhances the structure of the finger table.Based on Hilbert space filling curve,PChord realizes the mapping mechanism for multikeyword approximate searching.Compared with the Chord and Kademlia protocols,PChord evidently increases speed on resource searching and message spreading via theoretic proof and simulation results,while maintaining satisfactory load balance.展开更多
文摘A distributed processing system (DPS) contains many autonomous nodes, which contribute their own computing power. DPS is considered a unified logical structure, operating in a distributed manner;the processing tasks are divided into fragments and assigned to various nodes for processing. That type of operation requires and involves a great deal of communication. We propose to use the decentralized approach, based on a distributed hash table, to reduce the communication overhead and remove the server unit, thus avoiding having a single point of failure in the system. This paper proposes a mathematical model and algorithms that are implemented in a dedicated experimental system. Using the decentralized approach, this study demonstrates the efficient operation of a decentralized system which results in a reduced energy emission.
基金supported by the National Development and Reform Commission of China (CNGI-04-12-1D).
文摘The load balance is a critical issue of distributed Hash table (DHT), and the previous work shows that there exists O(logn) imbalance of load in Chord. The load distribution of Chord, Pastry, and the virtual servers (VS) balancing scheme and deduces the closed form expressions of the probability density function (PDF) and cumulative distribution function (CDF) of the load in these DHTs is analyzes. The analysis and simulation show that the load of all these DHTs obeys the gamma distribution with similar formed parameters.
基金supported by the National Natural Science Foundation of China (Grant No.60773041)the Natural Science Foundation of Jiangsu Province,China (No.BK2008451)+6 种基金the National High Technology Research and Development Program of China (No.2006AA01Z219)the High Technology Research and Development Program of Nanjing City (Nos.2007RZ106,2007RZ127)Foundation of National Laboratory for Modern Communications (No.9140C1105040805)Project supported by the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (No.07KJB520083)Special Fund for Software Technology of Jiangsu Province,Post-doctoral Foundation of Jiangsu Province (No.0801019C)Science&Technology Innovation Fund for Higher Education Institutions of Jiangsu Province (Nos.CX08B-085Z,CX08B-086Z)the six kinds of Top Talent of Jiangsu Province.
文摘As a solution for data storage and information sharing for peer-to-peer(P2P)networks,a novel distributed hash table(DHT)structure called PChord is presented in this paper.PChord adopts a bi-directional searching mechanism superior to Chord and enhances the structure of the finger table.Based on Hilbert space filling curve,PChord realizes the mapping mechanism for multikeyword approximate searching.Compared with the Chord and Kademlia protocols,PChord evidently increases speed on resource searching and message spreading via theoretic proof and simulation results,while maintaining satisfactory load balance.