Ruonan Rao

A Multiobjective Resources Scheduling Approach Based on Genetic Algorithms in Grid Environment

Resources scheduling plays an important role in grid. This paper converts resources scheduling problem in grid into a multiobjective optimization problem, and presents a resources scheduling approach based on multiobjective genetic algorithms. This approach deals with dependent relationships of jobs, and regards multi-dimensional QoS metrics, completion time and execution cost of jobs, as multiobjective. Based on Pareto sorting and niched sharing method, our approach determines optimal solutions. Experimental results show that our approach gets less completion time of jobs and total execution cost of jobs than min-min algorithm and max-min algorithm

DWSDM: A Web Services Discovery Mechanism Based on a Distributed Hash Table

Web services enable seamless application integration over the network regardless of programming language or operation system. A critical factor to the overall utility of Web services is an efficient discovery mechanism, but the existing Web services discovery is processed in centralized approaches such as UDDI, which has the limitations of single point of failure and performance bottleneck. In this paper, we propose a decentralized Web services discovery mechanism (DWSDM) based on a distributed hash table (DHT) to solve these problems. DWSDM leverages DHT as a rendezvous mechanism between multiple registry centers. Besides, the proposed layered architecture which decouples application tier for registry center and overlay tier for network topology could facilitate system implementation quickly. Experimental results on the prototype implementation based on improved Chord algorithm show that DWSDM achieves insignificant improvements on both robustness and scalability

ShanghaiGrid in Action: The First Stage Projects towards Digital City and City Grid

The nearest goal of ShanghaiGrid is to going to connect all supercomputers in this metropolis together to form a sharing environment for massive storage and grid computing. The first stage projects of ShanghaiGrid comprise four sub-projects, including 1) research on environment, protocols and standards of information gird infrastructure; 2) development of system software for information grid and establishment of four major grid nodes; 3) development of peer-to-peer based virtual research platform; 4) research on the application of grid based traffic-jam control and guidance. This paper introduces the background of ShanghaiGrid, provides a glimpse at features and challenges of its sub-projects, and summarizes the general goal of them.

Random walk search in unstructured P2P

Unstructured P2P has power-law link distribution, and the random walk in power-law networks is analyzed. The analysis results show that the probability that a random walker walks through the high degree nodes is high in the power-law network, and the information on the high degree nodes can be easily found through random walk. Random walk spread and random walk search method (RWSS) is proposed based on the analysis result. Simulation results show that RWSS achieves high success rates at low cost and is robust to high degree node failure.

The Delivery and Accounting Middleware in the ShanghaiGrid

The ShanghaiGrid is a Grid Computing Environment (GCE) being under construction based on the Grid Service standards and technologies in Open Grid Services Architecture (OGSA). The primary motivation of the grid is to build a general, shared Information Grid Platform and to terminate the history of the case-by-case designing pattern in the development of grids. In this paper, we give a brief introduction to the concept, infrastructure, and key technologies of the ShanghaiGrid. Particularly, we focus on the introduction of the Grid Services Delivery Toolkit and the Grid Accounting Toolkit, which play an important role in the ShanghaiGrid as Grid middleware.

Towards building intelligent transportation information service system on grid

Poor interpretability of current transportation systems has become an obstacle to further develop the intelligent transportation systems (ITS). Our design and implementation of intelligent transportation information service systems (ITIS) focuses on integrating heterogeneous data, transportation systems, and resources by using the grid technique. The ITIS project will refine and summarize the business model in Shanghai transportation information service system, design and set up open standards for intelligent transportation information service and simulation, develop grid supporting platform for transportation information service, integrate and fuse massive dynamic transportation data and legacy transportation systems, construct high performance computing (HPC) platform and dynamic parallel transportation simulation platform. ITIS will provide various high-level transportation information services for both citizens and government, which include optimal dynamic bus riding planning service, dynamic on-board navigation service, bus arrival-time prediction service, network optimization and simulation system, large-scale traffic-flow simulation system. Using these services will help to reduce the traffic congestion and other traffic problems, enhancing the transportation intelligence.

A grid-based application delivery toolkit for ubiquitous computing

In this paper we introduce a toolkit that is designed for distributing and launching applications in grid environments. The toolkit is an important part of Shanghai-Grid, an OGSA compatible grid computing environment being under construction for the large-scale collaboration and information sharing. The primary goal of the toolkit is to provide a facility for delivering the grid-based applications to various digital devices so that even a user of the mobile device can access the powerful grid services. Our toolkit has fully implemented the Java Network Launching Protocol 1.0. It also includes a bundle of APIs that support the grid-based applications.

Random walk spread and search in unstructured p2p

Unstructured Peer-to-Peer applications are very popular on the Internet. An efficient technique for improving performance of search method of these systems is to replicate file location information in P2P. In this paper we present random walk spread mechanism, and random walk spread and search method. Simulation results show that it achieves high success rates at low cost.

A formal model for the Grid Security Infrastructure

The Grid Security Infrastructure (GSI) proposed and implemented in Globus Toolkit has been a widely accepted solution for the security of grids in recent years. But there is no formal analysis or modelling on security mechanisms of GSI emerging in the literature yet. In this paper, we propose a formal logic, and formalize those primary security mechanisms using the logic. Our formalism not only is useful in understanding GSI but also provides us a substantial theoretic basis for some high-level security mechanisms to be developed based on GSI for the emerging service-oriented grid.

A Formal Logic for Shared Resource Access Control in the Grid

This paper presents a formal logic that can be used to model security mechanisms associated with the access-control of shared resources in the grid environment. The logic uses the K45 n , a standard modal logic of belief, and a fine-grained trust relationship to describe and reason about the access-control related issues. In this paper, the motivation, syntax, semantics, inference rules of the logic as well as how to encode credentials and security policies using the logic are introduced. An example that demonstrates how to use the logic in authorization decision making for resource requests within grid environment is also given.