Finding available services in TOSCA-compliant clouds

The OASIS TOSCA specification aims at enhancing the por-ta-bility of cloud applications by defining a language to describe and manage them across heterogeneous clouds. A service template is defined as an orchestration of typed nodes, which can be instantiated by matching other service templates. In this paper, we define and implement the notions of {em exact} and {it plug-in matching} between TOSCA service templates and node types. We then define two other types of matching ({em flexible} and {em white-box}), each permitting to ignore larger sets of non-relevant syntactic differences when type-checking service templates with respect to node types. The paper also describes how a service template that plug-in, flexibly or white-box matches a node type can be suitably adapted so as to exactly match it

Matching cloud services with TOSCA

The OASIS TOSCA specification aims at enhancing the portability of cloud-based applications by defining a language to describe and manage service orchestrations across heterogeneous clouds. A service template is defined as an orchestration of typed nodes, which can be instantiated by matching other service templates. In this thesis, after defining the notion of exact matching between TOSCA service templates and node types, we define three other types of matching (plug-in, flexible and white-box), each permitting to ignore larger sets of non-relevant syntactic differences when type-checking service templates with respect to node types. We also describe how service templates that plug-in, flexibly or white-box match node types can be suitably adapted so as to exactly match them

Modelling the behaviour of management operations in cloud-based applications

How to flexibly manage complex applications over heterogeneous clouds is one of the emerging problems in the cloud era. The OASIS Topology and Orchestration Specification for Cloud Applications (TOSCA) aims at solving this problem by providing a language to describe and manage complex cloud applications in a portable, vendoragnostic way. TOSCA permits to define an application as an orchestration of nodes, whose types can specify states, requirements, capabilities and management operations — but not how they interact each another. In this paper we first propose how to extend TOSCA to specify the behaviour of management operations and their relations with states, requirements, and capabilities. We then illustrate how such behaviour can be naturally modelled, in a compositional way, by means of open Petri nets. The proposed modelling permits to automate different analyses, such as determining whether a deployment plan is valid, which are its effects, or which plans allow to reach certain system configurations

An experimental analysis of abrasive water jet engraving of Italian marbles / Analisi sperimentale del processo di marcatura su marmi italiani tramite getto d’acqua ad alta pressione con abrasivo

English: This article concerns characterizing and optimizing the process of water-jet engraving on stone materials through experimental analysis. The purpose is to find possible relationships between work parameters for an abrasive water-jet and the geometrical parameters created by grooves. Samples of White Carrara and Perlato of Coreno marbles were used in testing. An optical profilometer was used to measure the transversal profile of the groove, objectively characterized by a number of measurements described in the article, including two parameters of visual quality. Statistical analysis made it possible to indicate optimal settings to enter on the basis of desired results; for example, increases in width, depth or the degree of groove contrast. Italian: Questo articolo affronta la caratterizzazione e ottimizzazione del processo di incisione di materiali lapidei mediante water jet attraverso un’analisi sperimentale. La finalità è trovare possibili relazioni tra parametri impostati per la lavorazione, tramite idrogetto con abrasivo, e parametri geometrici ricavati dai solchi. Per questo studio sono stati analizzati dei campioni di marmo Bianco di Carrara e di Perlato di Coreno. Per mezzo di un profilometro ottico è stato possibile misurare il profilo trasversale del solco, caratterizzato in maniera oggettiva tramite alcune misure descritte nell’articolo, inclusi due parametri di qualità visiva. Attraverso un’analisi statistica è stato possibile indicare le impostazioni ottimali da settare in base al risultato desiderato: es. aumento della larghezza, profondità o livello di contrasto del solco

SeaClouds: An Open Reference Architecture for Multi-Cloud Governance

A. Brogi, J. Carrasco, J. Cubo, F. D'Andria, E. Di Nitto, M. Guerriero, D. Pérez, E. Pimentel, J. Soldani. "SeaClouds: An Open Reference Architecture for Multi-Cloud Governance". In B. Tekinerdogan et al. (Eds.): ECSA 2016, LNCS 9839, pp. 334–338, 2016.We present the open reference architecture of the SeaClouds solution. It aims at enabling a seamless adaptive multi-cloud management of complex applications by supporting the distribution, monitoring and reconfiguration of app modules over heterogeneous cloud providers.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Analysing Multiple QoS Attributes in Parallel Design Patterns-Based Applications

Parallel design patterns can be fruitfully combined to develop parallel software applications. Different combinations of patterns can feature different QoS while being functionally equivalent. To support application developers in selecting the best combinations of patterns to develop their applications, we hereby propose a probabilistic approach that permits analysing, at design time, multiple QoS attributes of parallel design patterns-based application. We also present a proof-of-concept implementation of our approach, together with some experimental results

Self-healing trans-cloud applications.

Trans-cloud applications consist of multiple interacting components deployed across different cloud providers and at different service layers (IaaS and PaaS). In such complex deployment scenarios, fault handling and recovery need to deal with heterogeneous cloud offerings and to take into account inter-component dependencies. We propose a methodology for self-healing trans-cloud applications from failures occurring in application components or in the cloud services hosting them, both during deployment and while they are being operated. The proposed methodology enables reducing the time application components rely on faulted services, hence residing in “unstable” states where they can suddenly fail in cascade or exhibit erroneous behaviour. We also present an open-source prototype illustrating the feasibility of our proposal, which we have exploited to carry out an extensive evaluation based on controlled experiments and monkey testing.Open access funding provided by Universitá di Pisa within the CRUI-CARE Agreemen

Comparison of Static Analysis Architecture Recovery Tools for Microservice Applications

Architecture recovery tools help software engineers obtain an overview of their software systems during all phases of the software development lifecycle. This is especially important for microservice applications because their distributed nature makes it more challenging to oversee the architecture. Various tools and techniques for this task are presented in academic and grey literature sources. Practitioners and researchers can benefit from a comprehensive overview of these tools and their abilities. However, no such overview exists that is based on executing the identified tools and assessing their outputs regarding effectiveness. With the study described in this paper, we plan to first identify static analysis architecture recovery tools for microservice applications via a multi-vocal literature review, and then execute them on a common dataset and compare the measured effectiveness in architecture recovery. We will focus on static approaches because they are also suitable for integration into fast-paced CI/CD pipelines