Table Of ContentSPRINGER BRIEFS IN COMPUTER SCIENCE
Beniamino Di Martino
Giuseppina Cretella
Antonio Esposito
Cloud
Portability and
Interoperability
Issues and Current Trends
SpringerBriefs in Computer Science
More information about this series at http://www.springer.com/series/10028
Beniamino Di Martino Giuseppina Cretella
(cid:129)
Antonio Esposito
Cloud Portability
and Interoperability
Issues and Current Trends
123
BeniaminoDi Martino Antonio Esposito
Seconda Universitàdi Napoli Seconda Universitàdi Napoli
Aversa Aversa
Italy Italy
Giuseppina Cretella
Seconda Universitàdi Napoli
Aversa
Italy
ISSN 2191-5768 ISSN 2191-5776 (electronic)
SpringerBriefs inComputer Science
ISBN 978-3-319-13700-1 ISBN 978-3-319-13701-8 (eBook)
DOI 10.1007/978-3-319-13701-8
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Luca, Teresa, Virgilio, Francesca, Gio
Paola, Rosaria, Francesco
Preface
Cloud computing is emerging as the most promising technology for software
development,changingthewaycustomersinteractwiththeirdataandapplications.
There are many reasons that drive the choice of moving to cloud:
(cid:129) companies no longer need to buy, store, and maintain expensive hardware
infrastructures,reducingtimeandmoneyinvolvedinmaintaining,updating,and
repairing their own equipments;
(cid:129) hardware dimensioning is not to be related to peak workload any more, but the
infrastructure can be dynamically scaled according to the current needs. This
results in a better use of the existing resources;
(cid:129) customers pay only for the resources they actually use, following a “Pay as you
Go” paradigm;
(cid:129) using distributed resources, including data centers and computing nodes, can
enhance systems’ resiliency and disaster recovery;
(cid:129) thepossibilitytochooseamongabroadrangeofavailableresourcesandservices
can trigger strong competition between cloud providers, thus resulting in better
quality and lower prices for customers.
Theseareonlyafewofthepossiblebenefitsthatcouldderivefromtheadoption
of the cloud computing paradigm but, despite the diffusion of cloud technologies,
issues and limitations still exist. A major issue is the lack of portability and
interoperability between cloud platforms at different service levels, affecting the
cloudcomputingpanoramainseveralwaysandaspects.Thebrokering,negotiation,
management, monitoring, and reconfiguration of cloud resources are nowadays
challenging tasks for the developer or user of cloud applications due to different
businessmodelsassociatedwithresourceconsumptionaswellasduetothevariety
of services—and their features—offered by the variety of cloud providers. These
pointsbecomeverycriticalwhenthelandscapeisamulticloudenvironmentandthe
mainconcernisrepresentedbythevendorlock-inproblem.Infact,cloudproviders
usually propose technological solutions that differentiate them from their compet-
itors: these differences have the drawback of locking the customers as no
vii
viii Preface
alternativesareoffered.Thus,oncecustomershavechosenacloudprovider,either
they cannot change to another provider or they can do it but only at a huge cost.
Vendor lock-in risk also includes reduced negotiation power in reaction to price
increases and service discontinuation (if, e.g., the provider goes out of business).
In the following the structure of the book is illustrated.
In Chap. 1, the notions of cloud portability and interoperability are introduced,
together with the issues and limitations arising when such features are lacking or
ignored.Theillustrationstartswithdefinitionsofportabilityandinteroperabilityas
inherent to the generality of software systems, and then the concepts are tailored,
specialized, and exemplified for the specificity of cloud computing. Some basic
conceptsofthecloudandreferencearchitecturesarereportedtodefinetherecurrent
terms and roles.
Anumber of usecases, accompanied witha concrete case study, representing a
variety of interoperability and portability scenarios are illustrated. Several defini-
tions and use case scenarios are modeled by means of an n-dimensional feature
space, where features represent the different characteristics and abstraction levels
of the cloud domain.
The feature space, the use case scenarios, and the case study are utilized in the
following chapters in order to position, classify, and demonstrate the different
technologies and solutions presented.
Chapter 2 provides an overview of the state-of-the-art methodologies and
technologies, which are currently used or are being investigated to enable cloud
portability and interoperability. These include: Model-Driven Architecture (MDA)
and languages, semantic technologies, cloud patterns, and agent systems. We
illustrate in detail how the use of cloud patterns can enable robust cloud applica-
tions design and development with respect to portability and interoperability. We
positionthedifferentmethodologiesandtechnologiesillustratedwithrespecttothe
use case scenarios and features defined in Chap. 1, and we test them by analyzing
their application to the case study illustrated in Chap. 1. We also mention and
briefly illustrate the contributions coming from projects funded by the European
Commission FP7 program.
Chapter 3 illustrates the main cross-platform cloud application programming
interfacesandhowtheycansolveinteroperabilityandportabilityissuesbybringing
uniformity and standardization to the cloud. This chapter provides an overview of
initiatives that provide cross-platform-based cloud APIs such as DeltaCloud,
SimpleCloud, JCloud, Libcloud, and research projects whose aim is to provide
multicloud APIs (such as mOSAIC). Such APIs are positioned with respect to the
use case scenarios and features defined in Chap. 1, and tested by analyzing their
application to the case study illustrated in the chapter.
Chapter 4 presents a set of ready-to-go solutions which, either for their wide
diffusion in the cloud computing scenario or because they implement the estab-
lished or emerging standards (see Chap. 5), have a fundamental role in providing
interoperable and portable solutions. In particular, Amazon Web Services (AWS)
and OpenStack have imposed themselves as “de facto standards” atthe IaaS level,
since their wide adoption has led other providers to develop APIs and interfaces
Preface ix
whicharecompatiblewiththeiroffers.AtthePaaSlevel,MicrosoftAzure,Google
App Engine, IBM Bluemix, and OpenShift with their multi-language support and
ability to interface with other platform services, surely enhance the application
portability and thus deserve to be cited here. Such solutions are positioned with
respect to the use case scenarios and features defined in Chap. 1, and tested by
analyzing their application to the case study illustrated in the chapter. Finally, we
also present solutions that have been explicitly created for portability and inter-
operability purposes, such as Docker, ElasticBox, and Cloudify.
Chapter 5 presents an overview of the emerging standards for cloud interoper-
ability and portability. In particular, here we consider efforts moving toward the
definitionofsharedstandardsaddressingdifferentaspectsofthecloudenvironment,
spanning from services communication to data description. Among these, we
consider standards such as TOSCA, CIMI, OCCI, and CDMI. Some of these
standardsarepositionedwithrespecttotheusecasescenariosandfeaturesdefined
inChap.1,andtestedbyanalyzingtheirapplicationtothecasestudyillustratedin
the chapter.
We wish to thank Antonio Argenziano, Andrea Barbato, Graziella Carta, Sal-
vatore D’Angelo, Salvatore Maisto, Stefania Nacchia, and Raffaele Sperandeo for
their valuable contribution to the evaluation of the various platforms and solutions
described in the book.
Last but not least, we would like to acknowledge the excellent and relentless
supportoftheSpringerstaffmembers—inparticularViktoriaMeyer,RalfGerstner,
and Aliaksandr Birukou—during all phases of the development of this book.
Beniamino Di Martino
Giuseppina Cretella
Antonio Esposito
Contents
1 Cloud Portability and Interoperability. . . . . . . . . . . . . . . . . . . . . 1
1.1 Cloud Basics and Reference Architectures . . . . . . . . . . . . . . . 1
1.2 Cloud Interoperability and Portability Definitions . . . . . . . . . . 4
1.2.1 Cloud Computing Use Case Scenarios. . . . . . . . . . . . 6
1.2.2 A Case Study. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2 Methodologies for Cloud Portability and Interoperability. . . . . . . 15
2.1 Model-Driven Approach for Design, Provisioning,
Execution, or Migration to the Cloud . . . . . . . . . . . . . . . . . . 15
2.1.1 MDA in MODAClouds. . . . . . . . . . . . . . . . . . . . . . 15
2.1.2 MDA in ARTIST. . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.1.3 MDA in REMICS. . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.1.4 MDA in PaaSage . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.2 Semantic Approaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.2.1 Semantics in mOSAIC . . . . . . . . . . . . . . . . . . . . . . 23
2.2.2 Semantics in Cloud4SOA . . . . . . . . . . . . . . . . . . . . 25
2.2.3 Semantic Sky. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2.3 Multi-Agent Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2.3.1 Brokering, Negotiation, and Monitoring
with mOSAIC’s Cloud Agency. . . . . . . . . . . . . . . . . 28
2.3.2 Agent-Based Cloud Resource Management
Testbed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.4 Cloud Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
2.4.1 How Cloud Patterns Can Enable Interoperability
and Portability . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
2.4.2 IBM Virtual Patterns. . . . . . . . . . . . . . . . . . . . . . . . 31
2.4.3 Azure Cloud Patterns . . . . . . . . . . . . . . . . . . . . . . . 33
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