P. Victer Paul

QoS enhancements for global replication management in peer to peer networks

Replica Management is a key issue to reduce the bandwidth consumption, to improve data availability and to maintain data consistency in large distributed systems. Global Replica Management (GRM) means to maintain the data consistency across the entire network. It is preferable particularly for multi-group distributed systems. On the other hand, GRM is not favorable for many applications because a very large number of message passes is needed for replica management processes. In this paper, in order to reduce the number of message passes needed to achieve the efficient GRM strategy, an interconnection structure called the Distributed Spanning Tree (DST) has been employed. The application of DST converts the peer network into logical layered structures and thereby provides a hierarchical mechanism for replication management. It is proved that this hierarchical approach improves the data availability and consistency across the entire network. In addition to these, it is also proved that the proposed approach reduces the data latency and the required number of message passes for any specific application in the network.

Efficient service cache management in mobile P2P networks

Service oriented computing is growing as the prominent technology both in the technical and business perspectives. Due to the rapid growth in the volume of service repositories and services, obtaining the appropriate service is becoming tedious in the current scenario. Though advanced techniques are proposed to handle these challenges in conventional environments, still it is in its critical stage in the resource constrained scenarios, particularly in wireless mobile environments. The work presented in this paper proposes a Service Cache Management (SCM) for Mobile Peer-to-Peer (MP2P) networks to facilitate the efficient retrieval of services. We used a communication structure called Distributed Spanning Tree (DST), in which nodes of MP2P are made to form a forest of spanning trees in a distributed fashion. Using the DST structure, fast service cache and retrieval can be achieved within MP2P. Further to enhance the effectiveness of the proposed system, the DST network is optimized with Ant Colony Optimization (ACO), to identify the simplest path between nodes of each layer on the DST. The merits of the proposed techniques are demonstrated in terms of reduced time requirement for cached service search, increased availability, enhanced consistency, scalability and improved hit ratios.

Improving Efficiency of Peer Network Applications by Formulating Distributed Spanning Tree

Peer to Peer (P2P) networks are the important part of the next cohort of Internet. But in Peer networks, achieving required efficiency for any application is difficult. This is because efficiency of application evidently depends on the effective communication. For any communication process in peer network very large number of message passes needed because the message may go through a node multiple times. In order to limit the number of message passes needed for effective communication in any peer network, we follow an interconnection structure called Distributed Spanning Tree (DST) which defines each node as the root of a spanning tree. DST will make the peer network into a layered structure to improve the effective routing and data availability. In this paper, we propose a technique to formulate DST in peer network and determined efficiency improvement in various P2P applications using DST.

A new population seeding technique for permutation-coded Genetic Algorithm: Service transfer approach

Abstract Genetic Algorithm (GA) is a popular heuristic method for dealing complex problems with very large search space. Among various phases of GA, the initial phase of population seeding plays an important role in deciding the span of GA to achieve the best fit w.r.t. the time. In other words, the quality of individual solutions generated in the initial population phase plays a critical role in determining the quality of final optimal solution. The traditional GA with random population seeding technique is quite simple and of course efficient to some extent; however, the population may contain poor quality individuals which take long time to converge with optimal solution. On the other hand, the hybrid population seeding techniques which have the benefit of good quality individuals and fast convergence lacks in terms of randomness, individual diversity and ability to converge with global optimal solution. This motivates to design a population seeding technique with multifaceted features of randomness, individual diversity and good quality. In this paper, an efficient Ordered Distance Vector (ODV) based population seeding technique has been proposed for permutation-coded GA using an elitist service transfer approach. One of the famous combinatorial hard problems of Traveling Salesman Problem (TSP) is being chosen as the testbed and the experiments are performed on different sized benchmark TSP instances obtained from standard TSPLIB [54] . The experimental results advocate that the proposed technique outperforms the existing popular initialization methods in terms of convergence rate, error rate and convergence time.

Performance analyses over population seeding techniques of the permutation-coded genetic algorithm

A review on population seeding techniques for Permutation-coded Genetic Algorithm.Experiments are performed on large sized Traveling Salesman Problem instances.The experimentation analyses are carried out using ANOVA and DMRT statistical tools.Best performing population seeding techniques are identified w.r.t. assessment criteria. The genetic algorithm (GA) is a population based meta-heuristic global optimization technique for dealing with complex problems with very large search space. The population initialization is a crucial task in GA because it plays a vital role in the convergence speed, problem search space exploration and also the quality of the final optimal solution. Though the importance of deciding problem specific population initialization in GA is widely recognized, it is hardly addressed in the literature. In this paper, different population seeding techniques for permutation-coded genetic algorithm such as random, nearest neighbor (NN), gene bank (GB), sorted population (SP), selective initialization (SI) along with three newly proposed ordered distance vector based initialization techniques have been extensively studied. The ability of each population seeding technique has been examined in terms of a set of performance criteria such as computation time, convergence rate, error rate, average convergence, convergence diversity, nearest-neighbor ratio, average distinct solutions and distribution of individuals. One of the famous combinatorial hard problems of traveling salesman problem (TSP) is being chosen as the testbed and the experiments are performed on large sized benchmark TSP instances obtained from standard TSPLIB. The experimentation analyses are carried out using statistical tools to claim the unique performance characteristic of each population seeding techniques and best performing techniques are identified based on the assessment criteria defined and the nature of the application.

Ant Colony Optimization for Data Cache Technique in MANET

Mobile ad hoc networks (MANETs) are collection of distributed nodes which communicate using multi-hop wireless links. In order to manage the frequent topology change and ineffective communication, Distributed Spanning Tree (DST) interconnection technique can be used. DST technique guarantee network connectivity, efficient routing and maintain network performance in MANET. In MANET, nodes work for tasks of similar goal (common interest). So, most of the nodes try to access the similar data at different period. By using Data cache system (DCS), we can improve the efficiency of MANET to some extent [1]. In this paper, Ant Colony Optimization (ACO) technique is used to enhance the efficiency of data cache system in MANET at higher level. ACO technique improves the data transfer speed by finding optimal path between nodes of MANET in dynamic fashion. Analysis from simulation of our proposed work shows that data cache system efficiency can be improved using DST technique.

Algorithm and direction for analysis of Global Replica Management in P2P network

In the past decade, peer-to-peer (P2P) applications have made the main part of the Internet traffic. Data replication is generally used to improve the data availability, reduce data access delay and network traffic. Global Replica Management (GRM) is the method to preserve the replica consistent all through the network which is much required in major email, file hosting servers and in collaborative work environments. But GRM is not encouraging for many internet applications, since it increases the network traffic because of large number of message exchanges. In this paper, we have developed a comprehensive pseudo-code based algorithm for GRM in a tree structured P2P network. We have also discussed about the direction for performance analysis methodology for the algorithm to pave the way to justify its effectiveness.

Analytical inspection for Replica Management in WANET using Distributed Spanning Tree

Replica Management is an important methodology to reduce bandwidth utilization, to get better data accessibility and to preserve data consistency in Wireless Ad hoc Networks (WANET). Global Replica Management (GRM) is the method to preserve data consistent throughout the network which is necessary in many multi-locational collaborative applications. But GRM is not encouraging for those applications because of huge number of messagepasses are needed for replica management. To reduce the message passes required to accomplish GRM, we follow an connection organization called Distributed Spanning Tree (DST). In our previous work [1], an efficient technique for formulation of DST in wireless environment is dealt and analysis shows that the DST reduces the messagepasses required for communication between the nodes in wireless network. In this paper, we propose an analytical inspection on efficiency improvement in Replica management application in DST formulation wireless network over the ordinary wireless network.

A novel security model for cloud using trusted third party encryption

Cloud Computing is the recent trend in IT industry that changes the way the business is done by delivering computing as a service on demand to the user by pay per use model. Major advantages such as reduced cost, flexibility ensure cloud computing to be much sorted technology in the computing industry. Cloud computing moves the data to the large data centers which is not trustworthy as there is chance for the cloud service provider to misuse the data without the knowledge of the users. We introduce a novel model which reduces the fear of loss of data confidentiality in the cloud service provider side. This model has third party security vendor which takes care of encryption and decryption of the data based on the preference of the user. So data can reside safely on the cloud service provider side.

An effective model for QoS assessment in data caching in MANET environments

In Mobile Ad Hoc Network MANET, every neighbouring node is likely to have similar interests and need to access the similar data at different times. So, by caching the frequently accessed data item within MANET, it is possible to reduce the cost of accessing the same data from the external source. In this perspective, an effective data cache mechanism is proposed by Paul et al., using the distributed spanning tree as a communication structure to lessen network overload. As an enhancement, ant colony optimisation technique has been applied on DST to cope with the fragile nature of the MANET. In this paper, a theoretical model has been formulated to assess the performance factors such as cooperative cache, mobility and hand-off and routing technique. In addition to these, the performance improvement of DCM in MANET has been proved experimentally using cache hit and data consistency using appropriate simulation.