Shu-Ching Wang

Towards a Load Balancing in a three-level cloud computing network

Network bandwidth and hardware technology are developing rapidly, resulting in the vigorous development of the Internet. A new concept, cloud computing, uses low-power hosts to achieve high reliability. The cloud computing, an Internet-based development in which dynamically scalable and often virtualized resources are provided as a service over the Internet has become a significant issue. The cloud computing refers to a class of systems and applications that employ distributed resources to perform a function in a decentralized manner. Cloud computing is to utilize the computing resources (service nodes) on the network to facilitate the execution of complicated tasks that require large-scale computation. Thus, the selecting nodes for executing a task in the cloud computing must be considered, and to exploit the effectiveness of the resources, they have to be properly selected according to the properties of the task. However, in this study, a two-phase scheduling algorithm under a three-level cloud computing network is advanced. The proposed scheduling algorithm combines OLB (Opportunistic Load Balancing) and LBMM (Load Balance Min-Min) scheduling algorithms that can utilize more better executing efficiency and maintain the load balancing of system.

An Integrated Intrusion Detection System for Cluster-based Wireless Sensor Networks

A Wireless Sensor Network (WSN) consists of many low-cost, small devices. Usually, as they are deployed to an open and unprotected region, they are vulnerable to various types of attacks. In this research, a mechanism of Intrusion Detection System (IDS) created in a Cluster-based Wireless Sensor Network (CWSN) is proposed. The proposed IDS is an Integrated Intrusion Detection System (IIDS). It can provide the system to resist intrusions, and process in real-time by analyzing the attacks. The IIDS includes three individual IDSs: Intelligent Hybrid Intrusion Detection System (IHIDS), Hybrid Intrusion Detection System (HIDS) and misuse Intrusion Detection System. These are designed for the sink, cluster head and sensor node according to different capabilities and the probabilities of attacks these suffer from. The proposed IIDS consists of an anomaly and a misuse detection module. The goal is to raise the detection rate and lower the false positive rate through misuse detection and anomaly detection. Finally, a decision-making module is used to integrate the detected results and report the types of attacks.

A Three-Phases Scheduling in a Hierarchical Cloud Computing Network

Network bandwidth and hardware technology are developing rapidly, resulting in the vigorous development of the Internet. A new concept, cloud computing, uses low-power hosts to achieve high usability. The cloud computing refers to a class of systems and applications that employ distributed resources to perform a function in a decentralized manner. Cloud computing is to utilize the computing resources (service nodes) on the network to facilitate the execution of complicated tasks that require large-scale computation. Thus, the selecting nodes for executing a task in the cloud computing must be considered. However, in this study, a three-phases scheduling in a hierarchical cloud computing network is advanced. The proposed scheduling can utilize better executing efficiency and maintain the load balancing of system.

Optimal agreement protocol in malicious faulty processors and faulty links

Traditionally, the problems of Byzantine agreement, consensus, and interactive consistency are studied in a fully connected network with processors in malicious failure only. Such problems are reexamined with the assumption of malicious faults on both processors and links. The proposed protocols use the minimum number of message exchanges and can tolerate the maximum number of allowable faulty components to make each fault-free processor reach a common agreement for the cases of processor failure, link failure, or processor and link failure. >

Achieving efficient agreement within a dual-failure cloud-computing environment

Fault-tolerance is an important research topic in the study of distributed systems. To counter the influence of faulty components, it is essential to reach a common agreement in the presence of faults before performing certain tasks. However, the agreement problem is fundamental to fault-tolerant distributed systems. In previous studies, protocols dealing with the agreement problem have focused on a fully connected network or on a general connectivity. However, cloud-computing, an Internet-based development in which dynamically scalable and often virtualized resources are provided as a service over the Internet has become a significant issue. In a cloud-computing environment, the connected topology is not very significant. Therefore, previous protocols for the agreement problem are not suitable for a cloud-computing environment. To enhance fault-tolerance, the agreement problem in a cloud-computing environment is revisited in this study. The proposed protocol is called the Dual Agreement Protocol of Cloud-Computing (DAPCC). DAPCC achieves agreement on a common value among all nodes in a minimal number of message exchange rounds, and can tolerate a maximal number of allowable faulty components in a cloud-computing environment.

Towards a hybrid load balancing policy in grid computing system

Grid computing has become conventional in distributed systems due to technological advancements and network popularity. Grid computing facilitates distributed applications by integrating available idle network computing resources into formidable computing power. As a result, by using efficient integration and sharing of resources, this enables abundant computing resources to solve complicated problems that a single machine cannot manage. However, grid computing mines resources from accessible idle nodes and node accessibility varies with time. A node that is currently idle, may become occupied within a second of time and then be unavailable to provide resources. Accordingly, node selection must provide effective and sufficient resources over a long period to allow load assignment. This study proposes a hybrid load balancing policy to integrate static and dynamic load balancing technologies. Essentially, a static load balancing policy is applied to select effective and suitable node sets. This will lower the unbalanced load probability caused by assigning tasks to ineffective nodes. When a node reveals the possible inability to continue providing resources, the dynamic load balancing policy will determine whether the node in question is ineffective to provide load assignment. The system will then obtain a new replacement node within a short time, to maintain system execution performance.

A minimized makespan scheduler with multiple factors for Grid computing systems

Most scheduling heuristics applied to Heterogeneous Computing (HC) focus on the search of a minimum makespan, instead of the reduction of cost. However, relevant studies presume that HC is based on high-speed bandwidth and communication time has ignored. Furthermore, in response to the appeal for a user-pay policy, when a user submits a job to a Grid environment for computation each implementation of a job would be charged. Therefore, the Apparent Tardiness Cost Setups-Minimum Completion Time (ATCS-MCT) scheduling heuristic considers both makespan and cost, and it composes of execution time, communication time, weight and deadline factors. This study simulates experiments in a dynamic environment, due to the nature of Grid computing being dynamic. The ATCS-MCT is compared to frequent solutions by five scheduling heuristics. This study indicates that the ATCS-MCT achieves a similarly smaller makespan, and lower cost than Minimum Completion Time (MCT) scheduling heuristic, which is the benchmark of on-line mapping.

Reaching fault diagnosis agreement on an unreliable general network

Recently, Siu et al. failed in their attempt to use the FDAMIX protocol to eliminate the fault diagnosis agreement (FDA) problem with mixed faults on the processors in a general network. Therefore, in this study, a new protocol, the FDAL protocol, is introduced to solve the FDA problem with mixed faults on the links. The FDAL is capable of detecting/ locating faulty links to reconfigure the unreliable general network into a reliable network, and is able to increase the system performance and strengthen network integrity.

Reaching Agreement among Virtual Subnets in Hybrid Failure Mode

Fault-tolerance is an important research topic in the study of distributed systems. To cope with the influence of faulty components, reaching a common agreement in the presence of faults before performing certain tasks is essential. However, the Byzantine Agreement (BA) problem is a fundamental problem in fault-tolerant distributed systems. In previous studies, protocols dealing with the BA problem focused on static networks; however, these do not perform well in dynamically changing mobile networks. The most well known mobile network is the Mobile Ad-hoc Network (MANET). To enhance fault-tolerance and MANET reliability, the BA problem in virtual subnets of MANET is revisited in this paper. The proposed protocol is called the Hybrid Agreement Protocol (HAP). It achieves agreement on a common value among all functional mobile processors in a minimal number of message exchange rounds, and can tolerate a maximal number of allowable faulty components in the virtual subnet of MANET.

Byzantine Agreement on Mobile Ad-Hoc Network

Mobile Ad Hoc Network (MANET) has been more and more popular. MANET is a self-organizing, self-configuring and instantly deployable multi-hop wireless network in response to application needs without any fixed infrastructure. Moreover, the fault-tolerance and reliability of the MANET has also been an important topic. Toward this goal, we need a mechanism to allow a set of nodes to agree on a common value. The distributed Byzantine Agreement (BA) problem is one of the most important issues to take into consideration in designing a fault-tolerance system. In many cases, reaching a common agreement among fault-free nodes to cope with the influence from faulty components is crucial in a fault-tolerance system. In this study, the BA problem is visited in a MANET, in which the components may be subject to malicious fault.