Contents I. Introduction
Cloud computing is a model used to enable ubiquitous, convenient, on-demand network access to a variety of shared and configurable computing resources (e.g., networks, servers, storage, applications, and services). Not only can the cloud be rapidly provisioned and released, but this can be done with minimal management effort or service provider interaction [1] [2]. According to the abstraction level of the capability provided and the service model of providers, cloud computing services are divided into three classes: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). For instance Amazon Web Services and HP cloud services offer IaaS, where the users have privileges to start/stop the server to customize it by installing software packages, to attach virtual disks to it and to configure access permissions and firewall rules. Google AppEngine is an example of Platform as a Service offering a scalable environment for developing and hosting Web applications. The building blocks may include: a) in-memory object cache (memcache); b) mail service; c) instant messaging service based on XMPP (Extensible Messaging and Presence Protocol); d) image manipulation service; e) integration with Google Accounts authentication service. Salesforce.com relies on the SaaS model and it offers business productivity applications such as CRM (Customer Relationship Management) residing completely on their servers. Thus they allow the beneficiaries to customize and to access the applications on demand. OpenNetInf project is an open-source solution for the implementation of a cloud computing based on network of information [3]. NetInf relies on an information-centric communication paradigm and provides large-scale information dissemination, while also accommodating non-dissemination applications, including interpersonal communication. It inherently supports mobile and multi-access devices, capitalizing on their resources (for instance, storage). NetInf makes it easy and efficient to access Information Objects (lOs) without being concerned with or hampered by underlying transport technologies. Moreover, NetInf provides links between the physical and the digital world, its architecture offering an interface to an application-neutral communication abstraction based on Information Objects. The information model makes it possible to manage these objects in a secure fashion.
