A reliable communication system is one of the most crucial component in emergency response. Blockchain technology, known for its distributed and decentralized management, has been extensively used in various contexts, with interest also growing for its applications in the health-care sector. In this paper we propose and evaluate a system incorporating blockchain technology for initial emergency care interventions, i.e. ambulance dispatching. The approach allows a distributed management and coordination of emergency interventions, using smart contracts in place of a central authorithy. The major benefit is the increased ability to trace, and afterward give evidence of, the events occurring when handling emergency calls, without having to rely on a central authority. Moreover, the proposed system combines medical data records storing in the blockchain with additional cryptography to preserve the privacy of healthcare data, while ensuring availability, integrity and persistence.

We present a method, which incorporates knowledge awareness into the symbolic computation of discrete controllers for reactive cyber physical systems, to improve decision making about the unknown operating environment under uncertain/incomplete inputs. Assuming an abstract model of the system and the environment, we translate the knowledge awareness of the operating context into linear temporal logic formulas and incorporate them into the system specifications to synthesize a controller. The knowledge base is built upon an ontology model of the environment objects and behavioural rules, which includes also symbolic models of partial input features. The resulting symbolic controller support smoother, early reactions, which improves the security of the system over existing approaches based on incremental symbolic perception. A motion planning case study for an autonomous vehicle has been implemented to validate the approach, and presented results show significant improvements with respect to safety of state-of-the-art symbolic controllers for reactive systems.

As C/C++ has been widely used for several decades, a huge amount of C/C++ code is available. However, when using a modern processor having several cores, legacy code needs to be adapted for it to achieve the best performances. Modifying C/C++ code manually or automatically is not an easy task, given the complexity of the language. Moreover, it is paramount to check that the modified version keeps the emerging behaviour of the old one, except for the better performances. This paper proposes an automatic approach and the resulting tools to transform existing legacy C/C++ code for achieving parallel execution. The approach includes the automatic generation of test cases, customised for the code that has been converted into a parallel version. Test cases are auto-evaluating, hence a completely automatic cycle of code transformation, test generation, behavioural checking, has been achieved.

This report describes the scope of the VSC track held at the IEEE WETICE 2019 conference. The 2019 edition of WETICE was held in Capri (Naples), Italy, from June, the 12th to 14th. The papers accepted and presented to the VSC track dealt with the analysis of complex systems in order to detect erroneous or unexpected behaviour, especially from the security, and safety perspective.

This report describes the VSC track dealing with security and validation of software systems, within the IEEE WETICE 2017 conference. This year the conference and its tracks were held in Poznan, Poland, in June 21st to 23rd, 2017. The papers accepted and presented to the track dealt with malware detection and platform dependences.

This report provides an introduction to the papers accepted for the VSC track at IEEE WETICE 2016, held in Paris (France), from June 13th to 15th, 2016.

This report provides an introduction to the papers accepted for the VSC track at IEEE WETICE 2015, held in Larnaca Cyprus, from June 15th to 17th, 2015. The VSC track is the third IEEE WETICE event dedicated to systems validation techniques in the context of safety critical applications. Along the previous years the VSC track has provided reasearchers with a venue oriented to exchange results and ideas on the general context of software verification. Some papers have addressed issues related to hardware and software verification. This year we have received a significant number of contributions under the general theme of the track and for ensuring a high quality, by means of an independent reviewing process, we have selected three contributions for the presentation at the VSC track 2015. We thank all the anonymous reviewers and the programme committee members for their dedicated work. We express our gratitude to the WETICE General Chair, Program Chairs and Steering Committee for the opportunity given us to contribute with the VSC track to the lively and friendly research forum provided by the WETICE community.

We present a study on a significantly large and varied set of freely available Java virtual machines implementations. The aim of the study is to assess their level of conformity to the structural constraints of the Java language specification. In order to do that we set up a refined framework for the automated generation of a conformance checking test suite. In the framework, the test cases are generated by model checking the Java language specifications in order to target each a specific constraint. Complete coverage of all the modeled constraints within a limited number of tests is obtained by means of a combinatorial covering technique. Results obtained from the test suite application are presented and discussed and proved the efficacy and validity of the underlying approach to validation.

This report provides an introduction to the papers accepted for the VSC track at IEEE WETICE 2014.

We present a technique to fully automate the conformance testing of a Java virtual machine (JVM) implementation to the structural constraints it must satisfy to enforce type safety of program execution. The approach is based on formal modeling of the JVM as a finite state machine, ruled by the Java standard specifications. The model is used to derive a test suite and corresponding oracle that systematically explores the space of illegal states reachable by a JVM implementation under test. Also, a degree of conformance to the JVM specifications (i.e., too strict or too coarse) can be assessed by counting the number of false positives. Despite the huge test space, the entire proposed process need not human supervision. The technique is black box, fully automated, and can be applied for validating final products or during development i.e. for debugging purposes.

In this paper the CITLAB tool for Combinatorial Interaction Testing is presented. The tool allows importing/exporting models of combinatorial problems from/to different application domains, by means of a common interchange syntax notation and a corresponding interoperable semantic metamodel. Moreover, the tool is a framework allowing embedding and transparent invocation of multiple, different implementations of combinatorial algorithms. CITLAB has been designed tightly integrated with the Eclipse IDE framework, by means of its plug-in extension mechanism. It is intended to easy the spread of CIT testing both in industrial practice and in academic research, by allowing users and researchers to apply multiple test suite generation algorithms, each with its peculiarities, on the same problem models, and let them compare the results in order to select the one that best fits their needs, while alleviating from the pain of knowing all the different details and notations of the underlying CIT tools.

SUMMARY Combinatorial interaction testing (CIT) is a testing technique that requires covering all t‐sized tuples of values out of n parameter attributes or properties modelled after the input parameters or the configuration domain of a system under test. CIT test suites have shown to be very effective in software testing already at pairwise (t = 2) level, and the effectiveness of CIT grows with the tuple width t. Unfortunately, the number of tuples to be tested also does grow. In order to reduce the testing effort, researchers addressed the issue of computing minimal‐sized CIT test suites with effective and scalable algorithms. However, still very few generally applicable t‐wise covering construction algorithms (and tools) do exist in literature. This paper presents an original greedy algorithm to compute t‐wise covering mixed covering arrays with constant space complexity, irrespective of the number of involved parameters and strength of interaction. The proposed algorithm has been implemented in a prototype tool, featuring also support for user constraints over the inputs. Assessment of the tool performance on a set of large, real‐world test systems is reported, with results encouraging its adoption in industrial production environments. Copyright © 2011 John Wiley & Sons, Ltd.

Abstract To implement seamless mobility inside an integrated, multiple (e.g., GPRS/WiFi) access system, a vertical handover policy has to be devised. This is usually done at the mobile terminal, allowing it to be customized from an end‐user's perspective, in order to fit individual needs/preferences. We propose a new approach in taking vertical handover decisions, which are not anymore exclusively based on the knowledge of the available access networks' characteristics but also on higher level parameters which fall in the transport and application layers. To this extent, in this paper a model has been realized and simulations have been run in order to evaluate the impact of the vertical handover and its frequency on a set of typical user's network applications/services. We also take into account the user preferences in terms of cost and quality of service. We believe this approach reflects the optimal settings from the user's point of view with regard to his running services and applications. Our aim is to understand how to define a metric to be used in order to devise a solution which should try to balance the overall cost of vertical handovers with the actual benefits they bring to actual user's networking needs. This way, each mobile user could autonomously apply the handover decision policy, which is more convenient to his specific needs. Copyright © 2005 John Wiley & Sons, Ltd.

To provide IP mobility for wireless users several micro-mobility protocols are currently available. These are capable for supporting this feature inside the scope of a LAN, by means of performing handovers between adjacent WiFi radio-access cells in order to follow users' movements. Also, it is possible to achieve wireless mobility in a larger extent, i.e. across whole network domains. But, in order to do it these protocols have to be used in conjunction with a macro-mobility protocol, like mobile IP. In this context, a problem arises if such domains are so far away from each other that wireless-access gaps exist between them. In fact, this prevents wireless IP users from experiencing access continuity while traveling across these domains. In this paper we describe a solution, which was designed and implemented to cope with the above problem. Starting from the cellular IP protocol, we developed a new mobility framework that extends it to seamlessly manage roaming into the GPRS access network, whenever the mobile host is out of range from any WiFi domain. Also, management of inter-domain macro-mobility is integrated in our framework, eliminating the need to externally rely on mobile IP.

The combination of personal computing devices and wireless ad-hoc networks allows the concept of mobile ad-hoc information system, consisting of a highly dynamic, decentralized and self-organizing network of autonomous and mobile devices that interact as peers [M. Hannicainen et al. (2002), L. Kleinrock, (2000)]. Here we define a middleware layer, named Expeerience. We have decided to adopt as a basic software framework, an emerging P2P open technology such as JXTA. The second issue we address in this work is the integration of some code mobility support in the developed middleware to allow the distribution and execution of services on peers that originally do not own the service code. This has been introduced in our platform by adding a mobile code service, which enables to download and install new services dynamically only if necessary.

Seamless mobility is a requirement whose importance for Internet users nowadays is growing faster than ever Thus many solutions to manage wireless IP mobile access and inter-working with the fixed Internet are already available and more are currently being studied and improved In this paper we described an actual wireless mobility framework we designed and implemented in our university campus, which is spread over a wide metropolitan area. The aim is to let a mobile host, that is a user equipped i.e. with a PDA device, experience real wireless IP mobility while moving on a large spatial scale, by means of a middleware that leverages from three main wireless access technologies: Bluetooth, WiFi and GPRS. In our framework, these are managed as a hierarch), of spatially overlapping access domains. While the user is on the move, the client-side of the middleware running on our mobile PDA device triggers smart switchings between the currently best available and more appropriate wireless access path, based on locally collected information. On the other hand, the network-side part of the middleware manages mobile host location paging and routing-update functions inside the whole campus area with an approach which extends from the Cellular IP micromobility protocol. We call this approach WiFi bridge since it also adds mobile hosts with the capability to seamlessly travel between disjunct WiFi access domains inside the campus by means of a temporary relay onto the GPRS access domain. We implemented and tested the system in a real testbed using IPaq devices running Linux, obtaining encouraging experimental results.

The authors present the design and the implementation of a distributed media service provider for the Internet. The overall architecture consists of several remote video servers whose resources are merged into a logically unique and more powerful service provider. The basic abstraction layer needed to achieve inter-server resource coordination and user-server interoperability has been realized through the use of OMG's CORBA and SUN's Java facilities. The current implementation of the video servers is based on the DAVID video server developed at the University of Catania (http://sun195.iit.unict.it/david).

In this paper a prototype of a distributed video-on-demand server is presented. The technical aspects regarding the realization of this kind of service provider are dealt with, paying particular attention to exploiting the architecture the system is based on. The proposed system easily allows, in any broadband local network environment, the realization of a low-cost/high-performance distributed video server, through the clustering of the local workstations. The system has been implemented and tested, and the results of its performance and scalability are presented in the final sections of this paper.