Reliable Distributed System Research Articles

Reliable distributed systems: review of modern approaches

Called on to refine service-oriented architecture, a new architectural pattern named microservices emerged in the early two-thousands promising to speed up the delivery of new features. All of this is achieved by allowing many teams to work on separate autonomous parts of an application independently, though steepening the learning curve and introducing infrastructure-related issues. Overtime, while gaining more popularity, the initial meaning, as well as peculiarities of distributed systems development and reason for the use of the pattern, has turned out to be less prominent, instead becoming a sliver bullet for monolithic applications, which irreversibly leads to a tremendous increase in complexity of a system as well as other inherent problems. The absence of a single definition as well as the misleading name of the microservices pattern has all contributed to the development of the notoriously known distributed monolith. In this document, a review was conducted to resurrect the notion of microservices, understand their nature, and how and when the pattern should be applied. This is done by firstly understanding the difference between monolithic and distributed systems including their strengths and weaknesses, and defining the single most important reason for microservices to be used. The main part focuses on reducing the coupling in the system, which is the main obstacle during the development of a reliable and agile distributed system. Firstly, by modeling boundaries following domain teams and architectural needs, we ensure autonomous deployable units are created that provide independence during development, isolation, and reliability. Later by analyzing approaches to sharing data and communication, which are two major forces structuring a distributed system, we secure the previously established boundaries.

Modeling and Simulation of a Low-Cost Fast Charging Station Based on a Micro Gas Turbine and a Supercapacitor

In recent years, micro turbine technology has become a continuously reliable and viable distributed generation system. The application of distributed energy power generation sources, such as micro gas turbines (MGT), to charge electric vehicles offers numerous technical, economical benefits, and opportunities. MGT are considered as they are smaller than conventional heavy-duty gas turbines. They also are capable of accepting and operating with different fossil fuels in the range of low–high pressure levels as well as co-generation opportunities. The MGT could provide the fast and reliable output power guaranteed and needed for grid stability. This paper provides a mathematical representation, modelling, and simulation of a low-cost fast charging station based on a micro gas turbine and a super capacitor forming altogether a power generation system suitable for use especially as energy source in fast charging stations and dynamic power systems. All the micro gas turbine’s parameters are estimated according to available performance and operational data. The proposed system generates up to 30 kW output power assuming that it operates with natural gas. The developed model of the system is simulated in the environment of MATLAB/Simulink. Each part of the micro turbine generation system is represented by a mathematical model. On the basis of the developed model of the system, the minimum value of the supercapacitor was determined, which ensures the charging schedule of a selected electric vehicle.

A software design of the equipment management business in Digital Workshop

Firstly, the present situation and business requirements of the digital workshop equipment management business are designed, and a hierarchical functional architecture based on cloud platform is proposed, combined with the top-level function allocation and information integration model of the workshop equipment management business software. Then, combined with the discussion of the key points of software design, the technical approaches of vertical service support and horizontal interconnection integration, such as building a stable, reliable and low delay distributed system framework, real-time equipment state monitoring based on OPC UA, etc. Finally, the feasibility and effectiveness of the software design approach is further verified through the application practice of the equipment management business in an electronics product manufacturing workshop, which helps to improve the automation degree and real-time deterministic effect of the workshop equipment management business, and provides a reference for business planning and condition construction of similar enterprises’ digital workshop.

Towards Building Reliable and Cost-Efficient Distributed Storage Systems

Reliability and cost are two important targets for distributed storage systems. For many years, numerous schemes have been proposed to improve the reliability or cost of distributed storage systems, and they can be divided into three categories: (1) data redundancy schemes; (2) data placement schemes; and (3) data repair schemes. However, it is still unclear regarding how to build a reliable and cost-efficient distributed storage system, because (i) insufficient considerations on the combinations of different schemes; and (ii) insufficient considerations on failures and recoveries of different subsystems (racks, nodes, disks, and sectors). To measure the reliability and cost caused by different schemes, we design and implement CR-SIM, a Comprehensive Reliability SIMulator for distributed storage systems. It considers various affecting factors, such as the system topology, the data redundancy scheme, the data placement scheme, the data repair scheme, and the failure/recovery models of different subsystems. By using CR-SIM, we conduct various simulation-based experiments, and the experimental results reveal several important findings, which are helpful to build reliable and cost-efficient distributed storage systems. For public use, we have open-sourced our source code at https://github.com/yichuan0707/CR-SIM.

Your neighbors alleviate cold-start: On geographical neighborhood influence to collaborative web service QoS prediction

Predicting the unknown quality of service(QoS) for an active user who has not previously accessed a Web service plays a fundamental role in supporting appropriate service selection, high quality service composition and reliable distributed system construction. Existing Web service QoS prediction methods suffer from the problems of data sparsity and cold-start, which dramatically degrade prediction accuracy and even impede their applicability in real scenarios. Additionally, the potentially positive but inconspicuous relation between geographical region and QoS rating interaction among users and Web services has been underestimated in previous studies. In contrast to those studies, we propose a collaborative Web service QoS prediction approach that incorporates the knowledge of geographical neighborhoods. By analyzing the geographical relationships in the real-world dataset WSDream, we observe that users and Web services are positively correlated with their geographical neighbors. Based on this observation, we first design a bottom up neighborhood clustering method for correlating geographical neighbor selection. Then, we construct two diversified similarity neighborhood regularization terms and systemically integrate them into a matrix factorization model, which achieves the knowledge transfer of geographical neighborhoods in improving QoS prediction accuracy. Experimental results have demonstrated that our approach performs more efficiently than existing methods with respect to accuracy, as well as alleviating the data sparsity and cold-start issues.

Pithos

There has been significant research effort into peer-to-peer (P2P) massively multi-user virtual environments (MMVEs). A number of architectures have been proposed to implement the P2P approach; however, the development of fully distributed MMVEs has met with a number of challenges. In this work, we address one of the key remaining challenges of state consistency and persistency in P2P MMVEs. Having reviewed state management and persistency architectures currently receiving research attention, we have identified deficiencies such as lack of load balancing, responsiveness, and scalability. To address these deficiencies, we present Pithos—a reliable, responsive, secure, load-balanced, and scalable distributed storage system, suited to P2P MMVEs. Pithos is designed specifically for P2P MMVEs, and we show that it improves the reliability and responsiveness of storage architectures as compared to existing P2P state persistency architectures. Pithos is implemented as an OverSim simulation running on the OMNeT++ network simulation framework. It is evaluated using up to 10,400 peers, with realistic latency profiles, with up to 15.8 million storage and retrieval requests that are generated to store a total of 2.4 million objects. Each peer in Pithos uses a maximum of 1,950Bps bandwidth to achieve 99.98% storage reliability, while the most reliable overlay storage configuration tested only achieved 93.65% reliability, using 2,182Bps bandwidth. Pithos is also more responsive than overlay storage, with an average responsiveness of 0.192s, compared with the average overlay responsiveness of 1.4s when retrieving objects from storage.

Distributed Secret Sharing Approach With Cheater Prevention Based on QR Code

QR barcodes are used extensively due to their beneficial properties, including small tag, large data capacity, reliability, and high-speed scanning. However, the private data of the QR barcode lacks adequate security protection. In this article, we design a secret QR sharing approach to protect the private QR data with a secure and reliable distributed system. The proposed approach differs from related QR code schemes in which it uses the QR characteristics to achieve secret sharing and can resist the print-and-scan operation. The secret can be split and conveyed with QR tags in the distribution application, and the system can retrieve the lossless secret when authorized participants cooperate. General browsers can read the original data from the marked QR tag via a barcode reader, and this helps reduce the security risk of the secret. Based on our experiments, the new approach is feasible and provides content readability, cheater detectability, and an adjustable secret payload of the QR barcode.

Resource-aware hybrid scheduling algorithm in heterogeneous distributed computing

Today, almost everyone is connected to the Internet and uses different Cloud solutions to store, deliver and process data. Cloud computing assembles large networks of virtualized services such as hardware and software resources. The new era in which ICT penetrated almost all domains (healthcare, aged-care, social assistance, surveillance, education, etc.) creates the need of new multimedia content-driven applications. These applications generate huge amount of data, require gathering, processing and then aggregation in a fault-tolerant, reliable and secure heterogeneous distributed system created by a mixture of Cloud systems (public/private), mobile devices networks, desktop-based clusters, etc. In this context dynamic resource provisioning for Big Data application scheduling became a challenge in modern systems. We proposed a resource-aware hybrid scheduling algorithm for different types of application: batch jobs and workflows. The proposed algorithm considers hierarchical clustering of the available resources into groups in the allocation phase. Task execution is performed in two phases: in the first, tasks are assigned to groups of resources and in the second phase, a classical scheduling algorithm is used for each group of resources. The proposed algorithm is suitable for Heterogeneous Distributed Computing, especially for modern High-Performance Computing (HPC) systems in which applications are modeled with various requirements (both IO and computational intensive), with accent on data from multimedia applications. We evaluate their performance in a realistic setting of CloudSim tool with respect to load-balancing, cost savings, dependency assurance for workflows and computational efficiency, and investigate the computing methods of these performance metrics at runtime.

Effective Metadata Cluster Management for Mass Data Storage

An effective decentralized metadata management schema is critical to a reliable and scalable large-scale distributed storage system. With regard to the defects of huge expansion cost and high sensitivity to cluster alteration borne in both the hash-based and subtree-based metadata management schemas, a metadata server (MDS) clustering schema based on consistent hash structure, named DSVL, is proposed. By introducing virtual MDS into the consistent MDS cluster, it can effectively balance MDS cluster load. Besides, the standby mechanism and the lazy update policy are merged and applied to the MDS cluster to accomplish rapid MDS failover as well as zero data migration in case of cluster alteration. The results of prototype system and simulation test prove that DSVL, with the features of balanced metadata distribution, rapid failover, flexible scalability and zero data migration amount in case of node alteration, can meet the demands for flexible and effective management of large-scale data storage systems with ever increasing data amount.

Reaching Agreement in a Dual Fallible Cluster-Based Wireless Sensor Network

The reliability of the distributed system has been an important topic of research. Agreement problem plays a key role in the design of reliable distributed system, which allow the correct nodes to agree on a common value, have been brought up to aid the reliable execution of tasks. However, most existing agreement protocols are no longer practical in the wireless sensor network. In this paper, agreement problem is reexamined in a cluster-based wireless sensor network (CWSN). The purposed protocol can make all correct nodes reaching agreement with two rounds of message exchange and tolerant the maximal number of allowable fallible components.

Special Issue on the 9th International Symposium on Parallel and Distributed Computing

Welcome to this special issue on the ninth edition of International Symposium on Parallel and Distributed Computing (ISPDC) held in Istanbul in July 2010. ISPDC is dedicated to the advancement of state-of-theart in the area of parallel and distributed computing. The symposium program featured 28 full papers accepted out of 71 submitted papers. The program covered a wide spectrum of topics including parallel models and algorithms, interconnection topologies, GPU programming, grids, P2P, multicores and distributed systems. The three papers in this special issue were selected among the highest rated accepted papers and involve scientific programming on a wide spectrum of computational platforms, namely, Graphics Processing Units (GPUs), multi-cluster systems and grids. These three papers were extended and revised after a new round of review process before being published in Scientific Programming. The first paper titled “Improving accuracy for matrix multiplications on GPUs” by Badin et al. demonstrates the emergence of scientific programming research on Graphics Processing Units (GPU). The paper considers the problem of floating point arithmetic accuracy within the context of matrix multiplication on GPUs. On GPUs that lack double precision support, the problem of numerical accuracy becomes quite important. Hence, new algorithms that deliver high accuracy with little performance cost need to be developed. This paper addresses these issues and proposes doubly compensated summation and Kahan’s compensated summation based algorithms with little performance costs. The second paper titled “Performance models for the Spike banded linear system solver” by Manguoglu et al. investigates the problem of characterizing performance and scalability of banded preconditioners for linear system solvers. The authors develop parallel formulations of a banded solver, called the Truncated Spike solver. They present a highly accurate parallel performance model for the solver and establish the validity of the model on diverse heterogeneous multiclusters. Their performance model supported by actual runs demonstrates high scalability of their solver. The third paper “PetaShare: A reliable, efficient and transparent distributed storage management system” by Kosar et al. addresses the development of a distributed data management system for data-intensive e-science. The authors contribute a reliable and efficient distributed data storage system, called PetaShare, which spans multiple institutions over a wide geographic area. PetaShare provides a front-end with light-weight clients that enable easy, transparent and scalable access. A unified name space and efficient client data movement capability across geographically distributed storage sites are provided by PetaShare. The authors also present the details of their design and implementation and show performance results on reading/writing to remote PetaShare sites.

PetaShare: A Reliable, Efficient and Transparent Distributed Storage Management System

Modern collaborative science has placed increasing burden on data management infrastructure to handle the increasingly large data archives generated. Beside functionality, reliability and availability are also key factors in delivering a data management system that can efficiently and effectively meet the challenges posed and compounded by the unbounded increase in the size of data generated by scientific applications. We have developed a reliable and efficient distributed data storage system, PetaShare, which spans multiple institutions across the state of Louisiana. At the back-end, PetaShare provides a unified name space and efficient data movement across geographically distributed storage sites. At the front-end, it provides light-weight clients the enable easy, transparent and scalable access. In PetaShare, we have designed and implemented an asynchronously replicated multi-master metadata system for enhanced reliability and availability, and an advanced buffering system for improved data transfer performance. In this paper, we present the details of our design and implementation, show performance results, and describe our experience in developing a reliable and efficient distributed data management system for data-intensive science.

An Optimal Share Transfer Problem on Secret Sharing Storage Systems

We have been developing a secure and reliable distributed storage system, which uses a secret sharing scheme. In order to efficiently store data in the system, this paper introduces an optimal share transfer problem, and proves it to be, generally, NP-hard. It is also shown that the problem can be resolved into a Steiner tree problem. Finally, through computational experiments we perform the comparison of heuristic algorithms for the Steiner tree problem.

VAMNET

This article gives a design overview of a new reliable distributed operating system environment, combining the world of functional and distributed programming using a virtual machine approach for hiding system dependencies, offering rapid prototyping facilities. The basic operating system concepts used are derived from the Amoeba operating system by Andrew Tanenbaum and his work group, developed 20 years ago. VAMNET is not only a native operating system. It is a hybrid solution for expanding widely used operating systems like UNIX with a distributed execution environment.

The bounds of faulty components on consensus with dual failure modes

The consensus is an important topic in the reliable distributed system because the system can cope with the influences from faulty components when the agreement is achieved. Siu, Chin and Yang have indicated that the bound on the number of allowable faulty processors in Meyer and Pradhan's scheme is an overestimated one, and they have given a new fixed bound to the allowable faulty processors. However, we find out that the new bound for the allowable faulty processors by Siu et al. still seems to give the scheme too much credit. In this study, we shall give a more accurate estimation to the bound of the allowable faulty processors.

Reaching agreement on an unknown network with partial graphic information

The Byzantine Agreement (BA) is an important topic in the reliable distributed system because the system can cope with the influences from faulty components when the agreement is achieved. In the literature concerned, the BA problem has been well formulated in a Fully Connected Network (FCN) and a Generalized Connected Network (GCN) under the assumption that each processor in the network has the common knowledge of the graphic information about the entire network structure. However, in the real world, each processor may not have the common knowledge of the graphic information about the entire network structure. That is, the processors may only have the partial knowledge as to their own graphic information. In this paper, the Byzantine Agreement problem will be visited in an Unknown Network (UNet) to increase the capability of fault tolerance by allowing faulty processors with dual failure mode. The proposed protocols, the Unknown Agreement Protocol (UAP) and the Relay Channel (RC), use the minimum number of rounds of message exchange and can tolerate the maximum number of faulty processors allowed.

Guest editorial: special issue on reliable distributed systems

ESIGNERS of distributed systems are concerned with developing architectures, networking, software, algorithms, and applications. While research in this direction addresses some of the fundamental issues in distributed computing, topics related to modeling and simulation of multiple processor systems, real-time operation, reliability, fault tolerance, information assurance, performance measurements, and evaluation are also critical for the successful functioning of distributed systems. The purpose of this special issue is to serve researchers, designers, and implementers of distributed systems, with emphasis on system properties such as reliability, availability, and performability. In addition to conceptual advancement, this issue is intended to recognize the efforts that are aimed toward experimentation, testbeds, development, exploratory or emerging applications, and measurements from operational systems. The theme of this special issue was made to coincide with the 19th IEEE Symposium on Reliable Distributed Systems held at Nuernberg, Germany, 2000, but the topics and submissions were not restricted to the proceedings of this symposium. We received a total of 55 submissions, of which we selected 11 regular papers. Every submission was sent to at least five referees. We received a total of 201 reviews back from 141 referees. Several papers that are not included in this special issue have been forwarded for consideration in the regular issues of this transaction. Although we wanted to have a good mix of current, successful efforts, innovative ideas on reliable designs and open problems—both conceptual and experimental, the space limitation in the special issue and the type of submissions we received may have precluded some key topics of reliable distributed systems. Yet, we believe that the special issue encompasses major properties of a reliable distributed system. The selected papers are classified into four groups:

Disk Paxos

We present an algorithm, called Disk Paxos, for implementing a reliable distributed system with a network of processors and disks. Like the original Paxos algorithm, Disk Paxos maintains consistency in the presence of arbitrary non-Byzantine faults. Progress can be guaranteed as long as a majority of the disks are available, even if all processors but one have failed.

Digital Name: A New Access Entity for Organizing Fast Citizen Information System

The information regarding health, literacy rate, economic conditions, unemployment, population growth, law & order, criminal activities etc, about population of different parts of a country is needed by government, non-government and social welfare organizations. This information helps them to plan their socio-economic programs for the needed sections of the society. The compilation of this information is needed periodically so that feedback about the effectiveness of the programs launched for the socio-economic development can be examined and accordingly the programs can be modified and redirected. This requires a fast and reliable distributed population information database system, which can handle more number of queries per unit time. This paper introduces a new concept of Digital Name, which can be useful for organizing fast, reliable, economic and efficient nation wide distributed citizen information system.

Radiowave Tomography: A Case Study of Redeployable Distributed Control Underground

Radiowave tomography is a novel geophysical surveying technique, analogous to the medical CAT scan, which can produce images of the geology between two boreholes. This paper presents RT as an example of a reliable redeployable distributed system, employing intelligent borehole probes, automated winches and a portable PC. Optical fibres are used for robust links between equipment. Modularity and distributed control contribute to simple cabling and rapid testing.