Kuo-Qin Yan

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 hybrid load balancing policy underlying grid computing environment

In recent years, network bandwidth and quality has been drastically improved, even much faster than the enhancement of computer performance. The various communication and computing tasks in the fields such as telecommunication, multimedia, information technology, and construction simulation, can be integrated and applied in a distributed computing environment nowadays. However, as the demands of many researches for computing resources gradually grow, Grid Computing integrated with a distributed computing environment and the Internet (network) has gained more attention. The so-called Grid Computing is to utilize the idle computing resources (nodes) on the network to facilitate the execution of complicated tasks that require large-scale computing. In other words, the composition of Grid resources is dynamic and varies with time. Thus, when selecting nodes for executing a task, the dynamic of the nodes in the Grid must be considered, and to exploit the effectiveness of the resources, they have to be properly selected according to the properties of the task. This study proposed a hybrid load balancing policy which integrated static and dynamic load balancing technologies to assist in the selection for effective nodes. In addition, if any selected node can no longer provide resources, it can be promptly identified and replaced with a substitutive node to maintain the execution performance and the load balancing of the system.

Byzantine Agreement in a generalized connected network

Traditionally, the Byzantine Agreement (BA) problem is studied either in a fully connected network or in a broadcast network. A generalized network model for BA is proposed in this paper. A fully-connected network or a broadcast network is a special case of the new network architecture. Under the new generalized network model, the BA problem is reexamined with the assumption of malicious faults on both processors and transmission medium (TM), as opposed to previous studies which consider malicious faults on processors only. The proposed algorithm uses the minimum number of message exchanges, and can tolerate the maximum number of allowable faulty components to make each healthy processor reach a common agreement for the cases of processor failures, TM failures, or processor/TM failures. The results can also be used to solve the interactive consistency problem and the consensus problem. >

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.

Grouping Byzantine Agreement

The reliability of the distributed system has always been an important topic of research. Byzantine Agreement (BA) protocol, which allows the fault-free processors to agree on a common value, is one of the most fundamental problems studied in a distributed system. In previous works, the problem was visited in a fully connected network or an unfully connected network with fallible processors. In this paper, the BA problem is reexamined in a group-oriented network, which has the feature of grouping, and the network topology does not have to be fully connected. We also enlarge the fault tolerant capability by allowing dormant faults and malicious faults (also called as the dual failure mode) to exist in a group-oriented network simultaneously. The proposed protocol is more efficient than the traditional BA protocols and can tolerate the maximum number of tolerable faulty processors.

Asynchronous consensus protocol for the unreliable un-fully connected network

In order to achieve reliability in the distributed system, we need a mechanism to enable the system as a whole to continue to function despite the system has some faulty components. The Consensus problem is for the fault-free processors to cope with the faulty components and reach a common value from each other in the distributed system. Traditionally, the Consensus problems were solved in the synchronous network. Subsequently, Chandra and Toueg solved the Consensus problem with crash faulty processor in the asynchronous fully connected network in 1996. In this paper, we will solve the Consensus with dual failure mode (both crash fault and malicious fault) on communication links. The proposed protocol uses the minimum number of rounds of message exchange and can tolerate the maximum number of allowable faulty communication links to make each fault-free processor reach a common consensus value.