Martino Fornasa

VISIONS: A Service Oriented Architecture for Remote Vehicle Inspection

This paper presents a system for remote vehicle inspection developed within the VISIONS (vehicular system interface for open network service) research project funded by the European Commission. The system architecture allows digital service exchange between vehicles and road infrastructures (e.g., road, tunnel, terminal containers) and makes available a large set of significant vehicle data (e.g., engine status, tire pressure, cargo documents) directly to the infrastructure information system applications. The VISIONS system, based on the service oriented architecture, includes appropriate extensions to such an architecture to meet domain-specific requirements such as highly dynamic event handling and short service persistence in the network. The paper describes the architecture, the system prototype and the experimental results obtained in a pilot system located in the Mont Blanc Tunnel

A Platform for Smart Object Virtualization and Composition

One of the most challenging objectives of the Internet of Things (IoT) domain is the identification of interaction paradigms and communication standards to integrate smart objects (SOs), i.e., physical objects able to interact with the network. Such interaction paradigms and communication protocols belong to what can be called the IoT application layer, on which this paper focuses. This paper presents app execution platform (AEP), a platform that supports the design, deployment, execution, and management of IoT applications in the domain of smart home, smart car, and smart city. AEP was designed to coherently fulfill a set of requirements covered only partially or in a fragmented way by other IoT application platforms. AEP focuses on SO virtualization and on composite application (CA) orchestration and supports dynamic object availability.

Extensive GPRS Latency Characterization in Uplink Packet Transmission from Moving Vehicles

The GPRS (general packet radio service) broad availability is driving a widespread development of mobile telemetry systems for fleet management, supply chain management and dangerous goods monitoring applications. In this paper we present the results of extensive measurements of the GPRS network-layer uplink latency performed over a four-month period from about fifty road trucks using telemetry service, providing an uplink latency characterization in a moving vehicle environment. The results show the relationship between vehicle speed and latency. Furthermore, the performances of the stop-and-wait in a moving vehicle environment are evaluated in order to design a variant of such a protocol based on a vehicle speed-aware retransmission timeout.

Always-on distributed spreadsheet mashups

We present a platform that supports the creation of distributed data Mashups, implemented through the composition of multiple spreadsheets. The basic idea is to link cell ranges belonging to different spreadsheets in such a way to come up with a distributed spreadsheet. While such a behavior is already supported in private file spaces, our platform extends the operating principle and the functionality to the Internet in a secure way, using a SOA infrastructure as a communication bus. The platform consists of a client component, installed as a Plug-in in spreadsheet applications, and of a server component, accessible as a Web Service, that orchestrates the data exchanges among the client spreadsheets. One of the most original functionalities provided by the platform and described in the paper is that of guaranteeing the propagation of values along chains of linked spreadsheets even when some of the component spreadsheets are off-line. In addition to the description of the platform the paper also includes the description of a Spreadsheet Mashup framework specifically suited to hierarchical organizations such as those of enterprises. The architecture of the framework is presented in the light of a real-life example.

Development of a service-oriented architecture for the dynamic integration of mobile remote software components

The paper presents the work in progress of a project funded by the European Commissions aimed at enabling the integration between software components running on onboard truck terminals and ground based information systems to increase safety, efficiency and quality of road infrastructures. Despite the fact that the system originates in a automotive context, the architecture can be used for a wide range of control applications characterized by mobile software components. The system architecture goals are to collect vehicle data and make such data accessible from external information system through open application interfaces over standard wireless network technology

Collaboration and real-time analysis in the spreadsheet space

The SpreadSheet Space is a virtual space to connect spreadsheets. Users can configure permanent connections among spreadsheets as well as between spreadsheets and external data sources to keep their spreadsheets aligned among them and/or synchronized with external data sources. The paper focuses on two ways to exploit the Spreadsheet Space paradigm, namely Collaboration, which refers to spreadsheet alignment, and real-time data, which refers to synchronization with external data sources. In addition, the paper presents the architecture of the software platform which provides the operational and management services needed to support the SpreadSheet Space. The main idea proposed in this paper is to use Excel as a software client for collaboration and real-time data analysis.

Scalable Service Composition Execution through Asynchronous I/O

In the last few years different solutions have been proposed for the composition of Web APIs. In this paper we focus on the scalability problems appearing when the software platform in charge of executing Service Compositions (which are defined as Directed Acyclic Graphs, DAGs) is supposed to support huge numbers of concurrent executions. This is the case of viral applications as well as of Cloud Computing scenarios where Service Compositions are deployed and executed in multi-tentant platforms implementing different paradigms such as Business Process as a Service, Mashup as a Service, Service Composition as a Service. The proposed solution exploits the Asynchronous I/O paradigm for the efficient utilization of system resources such as threads and memory.

Event-Driven Mashup Orchestration with Scala

We describe the organization of a Server-side platform supporting the execution of Event-Driven Mashups (i.e., composite applications combining services and smart objects through events). To support a large number of concurrent Mashup executions, Mashup Execution Platforms (MEPs) must exploit the processing power of multi-processor computer architectures as well as appropriate concurrency models and programming languages. In order to do so, we describe a MEP based on the emerging Scala programming language which provides an efficient concurrency model - based on the actor model - that is suitable for the execution on multi-processor systems. Since the MEP architecture considered in this paper has been previously implemented in Java we also describe its porting from Java to Scala taking advantage of the compatibility between the two programming languages. Finally, the Java-based and the Scala-based implementations are compared from a performance point of view.

Experiments and Analysis on Hypervisor-Based Fault Tolerance in Virtualized Cloud Environments

Virtualization is the key technology for the Infrastructure as a Service (IaaS) paradigm in Cloud computing. A IaaS provider operates a hardware system on the top of which the users deploy their computing infrastructures, implemented as Virtual Machines. Such Virtual Machines may be required to guarantee different service levels, in particular for what concerns scalability and Fault Tolerance. The paper focuses on a promising technique called Hypervisor-based Fault Tolerance. The analysis is based on a set of ‘black-box’ experiments on the proprietary VMware’s technology called vSphere. The paper’s contributions include a description of how the VMware Fault Tolerance system works and a description of how the performance of different types of applications (in particular I/O-intensive and CPU-intensive) are affected by the inclusion of such a Fault Tolerance mechanism.

Passive access capacity estimation for QoS measurement

The passive estimation of Internet access capacity is interesting both from a scientific perspective, because it requires the development of techniques and tools to extract such a capacity from a noisy set of traffic measurements; and from an industrial perspective, because it supports, in principle, the possibility to measure the Service Levels of IP Access Service offered by Internet Service Providers. This paper proposes models, techniques and tools aimed at passively estimating the maximum achievable downlink network-layer rate (capacity) of an access link to the Internet from inside a network. We propose a method that extends the well-known packet-dispersion approach to network capacity estimation by considering longer TCP packet sequences to minimize the impact of measurement noise and to obtain reliable estimation without the need of a large amount of data. The proposed approach has been validated on some small-scale experiments performed on residential ADSL lines under different interfering traffic conditions.