In recent years, grid technology has emerged as an important tool for solving compute-intensive problems within the scientific community and in industry. To further the development and adoption of this technology, researchers and practitioners from different disciplines have collaborated to produce standard specifications for implementing large-scale, interoperable grid systems. The focus of this activity has been the Open Grid Forum, but other standards development organizations have also produced specifications that are used in grid systems. To date, these specifications have provided the basis for a growing number of operational grid systems used in scientific and industrial applications. However, if the growth of grid technology is to continue, it will be important that grid systems also provide high reliability. In particular, it will be critical to ensure that grid systems are reliable as they continue to grow in scale, exhibit greater dynamism, and become more heterogeneous in composition. Ensuring grid system reliability in turn requires that the specifications used to build these systems fully support reliable grid services. This study surveys work on grid reliability that has been done in recent years and reviews progress made toward achieving these goals. The survey identifies important issues and problems that researchers are working to overcome in order to develop reliability methods for large-scale, heterogeneous, dynamic environments. The survey also illuminates reliability issues relating to standard specifications used in grid systems, identifying existing specifications that may need to be evolved and areas where new specifications are needed to better support the reliability. Published in 2009 by John Wiley & Sons, Ltd.

This article is a U.S. Government work and is in the public domain in the U.S.A.

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Reliability in grid computing systems

This paper presents the first complete, integrated and end-to-end solution for ad hoc cloud computing environments. Ad hoc clouds harvest resources from existing sporadically available, non-exclusive (i.e. Primarily used for some other purpose) and unreliable infrastructures. In this paper we discuss the problems ad hoc cloud computing solves and outline our architecture which is based on BOINC.

Ad hoc Cloud Computing

Corporate bonds : quality and investment performance

ion could be that two modules with the same priority number can be permuted without changing the behavior of the system. Accordingly, the orbit relation partitions two global states into the same orbit if they can be transformed into each other simply by permuting the local states of the modules with the same priority number. As representatives, those states can be picked where e.g. the first module of the particular priority set is given the bus access. 2.1.5 A Novel Abstraction Approach Amongst verification and validation (V&V) approaches, formal verification is seeing increased usage and acceptance. One popular technique is model checking that allows for automated verification (without user guidance) by performing exhaustive simulation on the model of the system. However, model checking faces the problem of state space explosion. Abstraction is a general method to reduce the level of detail in order to reduce the complexity of analysis. Researchers at TU Darmstadt are working on a new technique that is tailored to the characteristic of a large class of distributed protocols [Serafini et al. 2006]. The basic observation is that many protocols exhibit a significant level of symmetry, which arises when all processes execute the same program and communication is synchronous and broadcast-based. Furthermore, most of the time the formulae to be verified are “plane”, i.e., they have the form “all correct processes enjoy a certain property”.ion is a general method to reduce the level of detail in order to reduce the complexity of analysis. Researchers at TU Darmstadt are working on a new technique that is tailored to the characteristic of a large class of distributed protocols [Serafini et al. 2006]. The basic observation is that many protocols exhibit a significant level of symmetry, which arises when all processes execute the same program and communication is synchronous and broadcast-based. Furthermore, most of the time the formulae to be verified are “plane”, i.e., they have the form “all correct processes enjoy a certain property”. The straightforward modeling of a distributed protocol entails modeling the behavior of a single process and then composing the processes together. As a consequence, the state of the system is represented as a tuple of states, one for each process. Our approach is instead to consider all the possible states that any correct process can assume at each round. At each round, we calculate the set of all the possible states of any correct process due to symmetric message exchange with the other correct processes and to the presence of faults. This allows representation of the state of the system as a set instead of as a tuple of states, leading to a considerable reduction of the size of the state space. The verification of global properties is then carried out by checking if the desired properties hold for all the states that any correct process can have. The key challenge is to prove that the abstraction process loses information but preserves certain properties. The abstraction is proved to be sound with respect to plane properties, i.e., if we can prove a plane property in the abstracted model then this also holds for the non-abstracted one. As we represent the set of states of any correct process, it is intuitively clear that our approach allows verification of properties that apply to each process individually, e.g., “each process shall have a variable within a given range”. In this case it is sufficient to visit all the possible states of a correct process and to verify that they satisfy the property of interest. It is more complicated to prove consistency properties, e.g., “all processes shall decide the same value”. For this purpose we partition the set of possible states of a process into consistency sets. At each round, it is guaranteed that if any two correct processes can have different states, these states belong to the same consistency set. The non-determinism in the evolution of the global system states determines the possibility of having several alternative consistency sets. Consistency properties are then required to hold only within each consistency set but not across them, e.g., “within each consistency set, all states shall have the same decision value”. For the sake of simplicity, the approach focuses on the verification problem for core fault tolerant protocols of frame-based, synchronous systems (e.g. consensus, atomic broadcast, diagnosis, membership). The approach, however, can be extended to model-checking of round-based asynchronous protocols. RESIST D12 verif p 16 Part Verif 2 – Model Checking Let us consider a scenario where such a protocol is symmetric (i.e., where each process performs the same operations) and there are no faults. If all processes start from the same initial state, they will perform the same state transitions at each round. Therefore, the state of the system could be modeled by representing only the common state of any process. Its evolution throughout rounds can thus be seen as a single thread. Each of these states is supposed to satisfy the desired properties of the protocol (safety and liveness). We can expand this model by considering the presence of different, asymmetric initial process states. The state of a correct process will now evolve as a tree, where at each round the state of each process at round i is derived according to the state of the other processes at round i − 1. Each combination of states at round i − 1 results in different branches of the tree at round i. At each round, a correct process will find itself in one state among a set of multiple possible states; these are the children of a common parent node. These sets are called consistency sets. Similarly to alternative subtrees, consistency sets are mutually exclusive. As in the previous case, all the possible states at each round, i.e., all the states within each consistency set, are supposed to enjoy the specified properties. When model checking fault tolerant protocols, however, the number of possible communication patterns and state transitions explodes due to the “extended” behavior of faulty nodes, particularly if the fault model allows them to communicate asymmetrically (e.g. under the Byzantine or the receive-omission fault assumption). This greatly increases the number of possible states and considerably reduces the symmetry of the system state. In our modeling approach, these further asymmetries are also handled using consistency sets. In fact, if the protocol is fault tolerant then the desired properties shall hold in spite of faults as well as of asymmetries in the possible initial states. To understand the concept of consistency set we can consider a very simple example of a synchronous system consisting of three processors, where one of the two can be faulty and symmetrically send incorrect messages. Assume that the domain of the messages is {0, 1, 2}. Say that all correct processes start from state S1 and produce the message 0 as initial message in the first round of the protocol. There are three possible states of a correct process after the first communication round: S2, if both processes are correct and send the message 0; S3 or S4, if one of the processes is faulty and symmetrically sends the message 1 or 2 respectively. In this case we would have two consistency sets: {S2, S3} and {S2, S4}. Consistency sets are mutually exclusive and reflect the non-determinism given by the possible presence of faulty messages. By construction, they allow us to deduce that we will never have a situation where one correct process has the state S3 and another correct process has the state S4 (although a correct process can assume both the states S3 and S4). Typically, abstraction techniques are defined considering general state models, for example Kripke structures. Such techniques are generally proved to be sound and complete and can be applied to model check any kind of specification, independent of the specific problem under examination. On the other hand, many papers reporting experiences on model checking distributed protocols introduce abstractions which are tied to the particular protocol and whose soundness and completeness are not shown but rather assumed as “sensible” (see for example [Steiner et al. 2004, Ramasamy et al. 2002]). Such an approach undermines the value of the results obtained by model checking. A contribution of our work is to introduce an abstraction scheme that, while specific for a class of distributed protocols, is rigorous enough to prove its properties mathematically. To achieve this, we first illustrate a modeling framework to express a distributed protocol (modified from [Dolev et al. 1986]). This somehow represents a higher level language if compared to normal specification languages used by model checkers. Then we show how to construct abstracted and nonabstracted models starting from the given specifications. Finally we prove that our abstracted models preserve soundness with respect to their corresponding non-abstracted models. RESIST D12 verif p 17 Part Verif 2 – Model Checking Using a specific protocol specification language, both the models are rigorously defined, allowing soundness and completeness to be proved. In contrast, much previous work on using abstractions to model check distributed protocols focused on defining the abstracted model. We claim that this approach should generally be applied when using domain specific abstraction, i.e. abstractions that are specific to a certain class of problems. Currently, we are running experiments to measure the gain of the abstraction (in terms of state space size and proof execution time). One of our running case studies is a consensus protocol to solve interactive (binary) consensus [Lamport et al. 1982]. 2.2 Process algebras and action-based model checking applied to fault-tolerant systems 2.2.1 Overview In [Bernardeschi et al. 2000], process algebras and action-based model chec

/pdf/resilience-building-technologies-state-of-knowledge-resist-4drhezakl7.pdf

Resilience-Building Technologies: State of Knowledge -- ReSIST NoE Deliverable D12

The aim of this study is to design and develop an autonomous fire proof rescue robot. The robot is designed in such a way, that it can traverse through fire and hazardous situations. Further, it will sense and communicate information regarding these situations in real time with the server. The robot is fixed with multi-sensors and further, a driver circuit has been integrated for communication in these hazardous situations through Zigbee and a data acquisition system (DAQ). In mechanical design first, a 3D solid model is generated using Solid works software to understand the basic structure of robot which provides information regarding robotic platform, size and location of various components. The developed fire fighting robot is a predominately outdoor ground-based mobile robotic system with onboard subdual systems that can traverse autonomously in the hazardous environment. The robot is designed such that it can traverse into the fire and send information regarding the fire behaviour and also the images of the victim’s location by using a camera. Further, a mathematical model which describes the kinematics and dynamic behaviour of robot motion are done. V-REP is used to create the simulation of the robot in a fire simulated fire environment. Finally, for the path planning, various techniques are discussed such as V-REPs inbuilt path planning module, A*, Fuzzy logic and artificial potential fields.

https://publications.drdo.gov.in/ojs/index.php/dsj/article/download/10237/6003

Modelling, Simulation and Mechatronics Design of a Wireless Automatic Fire Fighting Surveillance Robot

due to several reasons such as attentions given to design features and to modification from littler to medium sized system that results in trivial enhancement in performance.In spite of the tremendous achievement of grids which run parallel jobs, there still exists demand of requesting applications to avail opportunistic computing for considering the right selection of prerogative supercomputers. The objective of this research is to build a framework for on the fly computational commencing on socially convolved terrestrial grids to facilitate the sharing of computing workload over wireless networks as virtual supercomputers of unprecedented power. This will assist computing in heterogeneously interconnected mobile assets, Internet of Things, in crowdedscenarios for variable ranges like: stadiums, shopping centers, and so forth.

Quasi Opportunistic Supercomputing for Geospatial Socially Networked Mobile Devices

This paper aims at designing of adaptive framework for supporting collaborative work of different actors in public safety and disaster recovery missions. In such scenarios, firemen and robots communicate each other to reach a common goal. Here, reliable connection is mandatory to ensure the interaction between the actors. But wireless access network and communication resources are vulnerable in the event of a sudden unexpected change in the environment. Also, the continuous change in the mission requirements such as inclusion/exclusion of new actor, changing the actor's priority and the limitations of smart devices need to be monitored. To perform dynamically in such case, we present a framework based on a generic multi-level approach that ensures adaptation by semantic modeling.

https://hal.archives-ouvertes.fr/hal-00683638/document

Ontology-Based Collaborative Framework for Disaster Recovery Scenarios

Grid computing can exploit distributed, underutilized or not, resources to provide massive parallel CPU capacity. Load balancing, applications sharing, as well as geographically dispersed databases features are other Grid's aspects which are of interest for a telecommunications operator (Telco). Building a Grid middleware in order to implement Telco's services is thus a way to assess the validity of this type of architecture for future applications. To achieve a trustworthy platform, the middleware needs to take into account accidental or malicious faults which can impact different resilience aspects. This paper describes a secure and highly available architecture which, besides traditional Grid middleware functionalities (resource broker, job mapping, system monitoring, ...), makes use of fault-tolerant mechanisms (process duplication, failure handling, ...) to guarantee QoS defined in the service level agreement. Security is carried out by analyzing each node's defense capability issue and finding a suitable solution to match this with the appropriate user's job.

A Resilient Telco Grid Middleware

This paper aims at designing of adaptive framework for supporting collaborative work of different actors in public safety and disaster recovery missions. In such scenarios, firemen and robots interact to each other to reach a common goal; firemen team is equipped with smart devices and robots team is supplied with communication technologies, and should carry on specific tasks. Here, reliable connection is mandatory to ensure the interaction between actors. But wireless access network and communication resources are vulnerable in the event of a sudden unexpected change in the environment. Also, the continuous change in the mission requirements such as inclusion/exclusion of new actor, changing the actor's priority and the limitations of smart devices need to be monitored. To perform dynamically in such case, the presented framework is based on a generic multi-level modeling approach that ensures adaptation handled by semantic modeling. Automated self-configuration is driven by rule-based reconfiguration policies through ontology.

Ontology-based collaborative framework for disaster recovery scenarios

This work gives an account of the Credit Score web service application and the primary purpose of a credit score is to help lenders assess individuals' risk of not repaying a loan. Credit scoring assessment, despite the fact that a moderately new idea in the Indian money related business sector, have increased wide acknowledgment among financial specialists. In the meantime, easy-going and narrative confirmation recommends that there are worries among speculators and controllers about the execution of rating offices in India. This paper looks at financial specialists' mindfulness, discernment, understanding level and use of Credit scoring assessment through a poll-based example overview covering individual and additionally institutional speculators. We find high dissemination of rating use among all class of financial specialists, however, there is a recognizable upsetting with the dependability of appraisals, inclination of ensuing minimizing and opportuneness of rating reconnaissance. The review additionally uncovers that the institutional financial specialists have predominant information and comprehension about evaluations than individual speculators. In this way, the review underlines the requirement for rating offices to take a shot at instructing the basic speculators to engender appropriate comprehension and use of Credit

https://www.ijstr.org/final-print/mar2020/Secrecyprotector-A-Novel-Data-Analytics-Based-Credit-Score-Management-System.pdf

Sakkaravarthi Ramanathan

Papers

Quasi Opportunistic Supercomputing for Geospatial Socially Networked Mobile Devices

Ontology-Based Collaborative Framework for Disaster Recovery Scenarios

A Resilient Telco Grid Middleware

Ontology-based collaborative framework for disaster recovery scenarios

SecrecyProtector: A Novel Data Analytics based credit score management system