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A self-healing key distribution enables non-revoked users to recover the lost session keys on their own from the received broadcast messages and their private information. It decreases the load on the group manager and is very suitable for the unreliable wireless sensor networks. In 2008, Du and He [5] proposed a self-healing key distribution with revocation in wireless sensor networks which is claimed to resist to the collusion attack. In this paper, we show that the scheme 2 in [5] is not secure against the collusion attack. A newly joined user colluding with a revoked user can recover the group session keys that are not supposed to be known to them. Then the scheme will be improved and the modified one, through the analysis, is able to resist the collusion attack. Moreover, the modified scheme has the properties of constant storage, long life-span, forward secrecy and backward secrecy. [ABSTRACT FROM AUTHOR]

A significant modification of the mechanical behaviour of cement composites is brought about by fibre reinforcement. The most important feature is crack bridging by fibres. This leads to pseudo strain-hardening in SHCC. The important feature to be considered for durability design of SHCC, which is the focus in this report, is the crack-control exhibited by this class of materials in the strain-hardening phase. The crack control in SHCC subjected to mechanical actions leading to direct tension, but also shear and compression is described here. Short term monotonic actions, long-term actions as well as cyclic actions are discussed. Another mechanical degradation process, namely that of abrasion is described. Finally, self-healing of SHCC is discussed as a promising durability feature of degradation reversal. [ABSTRACT FROM AUTHOR]

The paper forms a basic classification of wireless networks basing on the subsequent functionalities provided by different topologies in comparison to the wired network. Then the focus is placed on the idea of a wireless mesh network as a structure freely mobile and versatile providing many extremely interesting and innovative opportunities in industrial, real-time communication systems. A set of following measurements verifies usability of one of the most popular mesh-based topology control protocols – Spanning Tree Protocol – in terms of different kinds of time-deterministic systems or high reliability systems. In the end final conclusion and an attempt to point the most intriguing issues and directions of research and development is made. [ABSTRACT FROM AUTHOR]

The main intention of this paper is to introduce the proposition of a new role-based approach to self-healing monitoring. This is preceded by an overview of existing approaches to the monitoring of distributed systems using self-healing features. Starting with a discussion of autonomous monitoring systems, we will come to self-healing systems. These systems should be able to automatically resolve the problems that occur in a system under monitoring. The paper provides insight into various aspects of self-healing monitoring systems at the software and hardware level. A detailed description of a new agent-based system, AgeMon, is covered later on. The system is based on the roles played by different types of agents. The self-healing features can be achieved by a form of cooperation of agents, e.g. monitoring agents, rule agents, database agents. The paper discusses the roles and gives an implementation background. [ABSTRACT FROM AUTHOR]

Runtime performance evaluation is necessary for the continuous QoS (Quality of Service) management of Web service-based applications. The analysis is critical in service provisioning since it allows to detect QoS degradation and to identify its source. However, performance analysis in current applications is usually based on QoS reference values that are manually instrumented and pre-established independently from the execution context. It is inflexible to change. The paper extends our previous research on performance evaluation within a self-healing framework and proposes a novel analysis approach based on automatic generation of QoS reference values. These QoS reference values are generated whenever we start the application execution in a new context. This approach enables the detection of QoS degradation, the identification of its nature (like execution or communication level) and the localization of its cause (as scalability issue, node failure or network overload). The carried out experiments show that the dynamic generated QoS reference values are suitable and their associated analysis results are accurate. [ABSTRACT FROM AUTHOR]

The paper considers the complex behavior of a small company in a business ecosystem, time by time leader or supplier or both in one or more supply chains, and points out the data exchange and processing problems it must face for reacting fast to customer requests. Then the paper suggests that in order to meet these requirements it is convenient to provide every company with proper automatic functions, covering its distributed planning, resource scheduling and exception handling needs, whose policies can be fully customised by the company itself to mirror its specific intentions: in short, a practical implementation of the autonomic model. [ABSTRACT FROM AUTHOR]

We propose a solution to achieve a global self-healing process based on local knowledge of each network element using a model-based diagnosis approach. Then we illustrate this solution in an IMS platform and detail the corresponding causal graph and diagnosis process. [ABSTRACT FROM AUTHOR]

The paper describes methods and tools addressing self-healing and resilience of critical infrastructures, specifically power and information networks. Our case study is based on challenges addressed in the ongoing EU project INTEGRAL aiming at integrating DES/RES in cell-based virtual utilities. We propose two experimental environments, EXP II and INSPECT to support a structured approach in identifying, implementing and monitoring suitable self-healing mechanisms entailing an increasing system resilience in our systems. Our approach is based on own results from earlier EU projects and selected approaches from other international projects such as NSF GENI in the US and EU efforts such as SmartGrids and ARECI. [ABSTRACT FROM AUTHOR]

Web services are becoming progressively popular in the building of both inter- and intra-enterprise business processes. These processes are composed from existing Web services based on defined requirements. In collecting together the services for such a composition, developers can employ languages and standards for the Web that facilitate the automation of Web service discovery, execution, composition and interoperation. However, there is no guarantee that a composition of even very good services will always work. Mechanisms are being developed to monitor a composition and to detect and recover from faults automatically. A key factor in such self-healing is to know what faults to look for. If the nature of a fault is known, the system can suggest a suitable recovery mechanism sooner. This paper proposes a novel taxonomy that captures the possible failures that can arise in Web service composition, and classifies the faults that might cause them. The taxonomy covers physical, development and interaction faults that can cause a variety of observable failures in a system΄s normal operation. An important use of the taxonomy is identifying the faults that can be excluded when a failure occurs. Examples of using the taxonomy are presented. [ABSTRACT FROM AUTHOR]

Cloud computing requires a robust, scalable, and high-performance infrastructure. To provide a reliable and dependable cloud computing platform, it is necessary to build a self-diagnosis and self-healing system against various failures or downgrades. This paper is the first to study the self-healing function, a challenging topic in today΄s clouding computing systems, from the consequence-oriented point of view. To fulfill the self-diagnosis and self-healing requirements of efficiency, accuracy, and learning ability, a hybrid tool that takes advantages from Multivariate Decision Diagram and Naïve Bayes Classifier is proposed. An example is used to demonstrate that this proposed approach is effective. [ABSTRACT FROM AUTHOR]

Networked embedded systems which operate in unattended areas with rare maintenance often make use of redundant resources for guaranteeing reliable service. In this paper, we will present novel concepts for dynamically partitioning and assigning functionality to software as well as hardware reconfigurable resources in a network. As a result, self-adaptive and self-healing systems emerge with a good tradeoff between redundancy and reliability. The proposed concepts are embedded in a three step approach, which 1.) reestablishes the functionality after a resource defect, 2.) optimizes the binding of the running tasks and 3.) creates new replicas of the tasks in the network. In this contribution, we will give an overview over all three parts, but focus on the second step. For this second step, called dynamic hardware/software partitioning, we will present algorithms, theoretical optimality bounds for workload distributions as well as experimental results. [ABSTRACT FROM AUTHOR]

Current embryonic attempts at software self–healing produce mechanisms that are often oblivious to the semantics of the code they supervise. We believe that, in order to help inform runtime repair strategies, such systems require a more detailed analysis of dynamic application behavior. We describe how to profile an application by analyzing all function calls (including library and system) made by a process. We create predictability profiles of the return values of those function calls. Self–healing mechanisms that rely on a transactional approach to repair (that is, rolling back execution to a known safe point in control flow or slicing off the current function sequence) can benefit from these return value predictability profiles. Profiles built for the applications we tested can predict behavior with 97% accuracy given a context window of 15 functions. We also present a survey of the distribution of actual return values for real software as well as a novel way of visualizing both the macro and micro structure of the return value distributions. Our system helps demonstrate the feasibility of combining binary–level behavior profiling with self–healing repairs. [ABSTRACT FROM AUTHOR]

Self-healing and recovery informed by environment knowledge (SHRIEK) is an autonomic computing approach to improving the robustness of computing systems. Case-based reasoning (CBR) is used to guide fault diagnosis and enable learning from experience, and rule-based reasoning to enable fault remediation and recovery informed by environment knowledge. Focusing on the role of conversational CBR (CCBR) in the management of faults that rely on user interaction for their detection and diagnosis, we present a hypothesis-driven approach to question selection in CCBR that aims to increase the transparency of CCBR dialogues by enabling the system to explain the relevance of any question the user is asked. We also present empirical results which suggest that there is no loss of problem-solving efficiency in the approach. Finally, we investigate the effects of the environment awareness provided by autonomous information gathering in SHRIEK on the efficiency of CCBR dialogues. [ABSTRACT FROM AUTHOR]

In this paper, we analyze an existing constant storage self-healing key distribution scheme in wireless sensor networks. Then, we show two attacks and propose a modified scheme to overcome the two flaws. At last, we propose a new self-healing key distribution scheme to improve the modified scheme. The most prominent properties of the new proposed scheme are as follows: achieving forward and backward secrecy and resisting to a collusion attack. So that a revoked user with the assistance of the newly joined users cannot get any information of group session keys which it is not entitled to get. [ABSTRACT FROM AUTHOR]

Software systems have become too complex to manage and fix manually. An emerging approach to overcome this problem is software self-healing. Studies in related disciplines have offered several self-healing solutions, however these usually address a single class of problems, or they are not applicable in fielded systems. To address the industrial need for software self-healing, we have initiated the EU SHADOWS project. This project concentrates on self-healing of complex systems, extending the state-of-art in several ways. It introduces pioneering technologies to enable the systematic self-healing of classes of failures which are not solved by other approaches. It additionally introduces an approach to the integration of several self-healing technologies in a common solution framework. It also adopts a model-based approach, where models of desired software behavior direct the self-healing process. Combined, these allow for lifecycle support of software self-healing, applicable to both academic and industrial systems. [ABSTRACT FROM AUTHOR]

Even though self-healing techniques for transactional processes have attracted enough attention in recent years, several critical issues regarding the distributed systems have not been addressed. For example, if we do the recovery under sustained attacks, in which condition the recovery can terminate? Is a synchronized clock necessary for distributed recovery? In this paper, we proposed a dead-lock free algorithm for coordinated recovery and answered related questions. We also proved that under specific situations, we have to freeze the recovery scheme to guarantee that the recovery can make progress. [ABSTRACT FROM AUTHOR]