Cluster-Based Load Balancing Algorithms for Grids

E-science applications may require huge amounts of data and high processing power where grid infrastructures are very suitable for meeting these requirements. The load distribution in a grid may vary leading to the bottlenecks and overloaded sites. We describe a hierarchical dynamic load balancing protocol for Grids. The Grid consists of clusters and each cluster is represented by a coordinator. Each coordinator first attempts to balance the load in its cluster and if this fails, communicates with the other coordinators to perform transfer or reception of load. This process is repeated periodically. We analyze the correctness, performance and scalability of the proposed protocol and show from the simulation results that our algorithm balances the load by decreasing the number of high loaded nodes in a grid environment.Comment: 17 pages, 11 figures; International Journal of Computer Networks, volume3, number 5, 201

Fault Tolerant Resource Allocation for Query Processing in Grid Environments

International audienceIn this paper, we propose a new algorithm for fault-tolerant resource allocation for query processing in grid environments. For this, we propose an initial resource allocation algorithm followed by a fault-tolerance protocol. The proposed fault-tolerance protocol is based on the passive replication of stateful operators in queries. We provide theoretical analyses of the proposed algorithms and consolidate our analyses with the simulations

Complex networks: an algorithmic perspective

Network science is a rapidly emerging field of study that encompasses mathematics, computer science, physics, and engineering. A key issue in the study of complex networks is to understand the collective behavior of the various elements of these networks.Although the results from graph theory have proven to be powerful in investigating the structures of complex networks, few books focus on the algorithmic aspects of complex network analysis. Filling this need, Complex Networks: An Algorithmic Perspective supplies the basic theoretical algorithmic and graph theoretic knowledge needed by every

Cluster Based Distributed Mutual Exclusion Algorithms for Mobile Networks

Abstract. We propose an architecture that consists of a ring of clusters for distributed mutual exclusion algorithms in mobile networks. The mobile network is partitioned into a number of clusters periodically using a graph partitioning algorithm called Fixed Centered Partitioning first. Each cluster is represented by a coordinator node on the ring which implements various distributed mutual exclusion algorithms on behalf of any member in the cluster it represents. We show the implementation of Ricart-Agrawala and Token-based algorithms on this architecture. The message complexities for both algorithms are reduced substantially using the proposed architecture...

A Real-time Total Order Multicast Protocol

Abstract. We describe, analyze and submit results of a real-time total order multicast protocol developed on a distributed real-time system architecture that consists of hierarchical rings with synchronous packet delivering characteristics. The protocol is structured on and closely interacts with the distributed clock synchronization and the real-time group management modules. The synchronous characteristics of the protocol makes it suitable for hard real-time applications where total ordering is required. The complexity analysis of the protocol is given and the performance results are shown for several scenarios. We show that the developed protocol is correct, scalable and real-time...

A Replication-based Fault Tolerance Protocol using Group Communication for the Grid

Abstract. We describe a replication-based protocol that uses group communication for fault tolerance in the Computational Grid. The Grid is partitioned into a number of clusters and each cluster has a designated coordinator that manages the states of the replicas within its cluster. The coordinators belong to a process group and the proposed protocol ensures the correct sequence of message deliveries to the replicas by the coordinators. Any failing node of the Grid is replaced by an active replica to provide correct continuation of the operation of the application. We show the theoretical framework along with illustrations of the replication protocol and its implementation results and analyze its performance and scalability.

A Hierarchical Connected Dominating Set Based Clustering Algorithm for Mobile Ad Hoc Networks

15th IEEE International Symposium on Modeling, Analysis and Simulation of Computer and Telecommunication Systems -- OCT 24-26, 2007 -- Bogazici Univ, Dept Comp Engn, Istanbul, TURKEYWOS: 000265212400009We propose a hierarchical Connected Dominating Set (CDS) based algorithm for clustering in Mobile Ad hoc Networks (MANETs). Our algorithm is an extension of our previous Connected Dominating Set Based Clustering (CDSC) Algorithm [1]. We extended the levels of the CDS to two levels and improved functionality at each level by providing additional rules to make sure that every node belongs to a single cluster. In the first level of the algorithm, the elements of the CDS are formed, based on CDSC Algorithm heuristics with improved functionality. The second level of the algorithm is executed among the CDS elements to find the second level CDS where each element belonging to the set represents a group of CDS elements, therefore a group of clusters. We show that this approach is more scalable and simpler to implement than a single level algorithm and that it also provides more balanced two level clusters due to its distributed nature. We also show that the number of levels of the algorithm can be extended to more than two layers providing more populated clusters, therefore providing a level of cluster and group membership structure within the MANET. This hierarchical groups can be used for different application needs at each level such as multi-cast communication or security purposes in MANETs.IEEE, IEEE Comp Soc, AC