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Over the last decade the bandwidth required for services such as High Definition TV and Internet has grown explosively. Telecom operators are developing business cases evaluating the deployment of high speed Fiber to the Home (FTTH) networks. The major limiting factor is the deployment cost, mostly related to civil works. Consequently, telecom operators often hesitate to invest and delay the deployment of FTTH networks or opt for gradual and slow deployment. Current FTTH deployment strategies are often motivated by business cases focused on cost aspects. This leads to a deployment strategy minimizing the cost or - for a fixed investment - maximizing the network coverage. This paper introduces a new methodology that identifies the optimal areas for deployment by maximizing the overall return on investment. Through the combination of GIS-based network design and geomarketing-based revenue projections, an increase in revenue of more than 10% can be obtained for the same initial investment.

International audience; This paper presents a context-based awareness mechanism designed for users who access web-based collaborative systems using mobile devices. The limited capabilities of such devices (reduced display size, limited battery and memory capacity...) constitute intrinsic constraints which make even more tenuous the issue of delivering relevant information to collaborative mobile users. We propose here an object-based representation of the notion of context and an awareness mechanism which filters the available information according to both the physical (user's location and device) and organizational (knowledge relative to the collaborative process) contexts of the user.

International audience; Over the years, organizations acquired disparate software systems, each answering one specific need. Currently, the desirable outcomes of integrating these systems (higher degrees of automation and better system consistency) are often outbalanced by the complexity of mitigating their discrepancies. These problems are magnified in the decentralized setting (e.g., cross-organizational cases) where the integration is usually dealt with ad-hoc "glue" connectors, each integrating two or more systems. Since the overall logic of the integration is spread among many glue connectors, these solutions are difficult to program correctly (making them prone to misbehaviors and system blocks), maintain, and evolve. In response to these problems, we propose ChIP, an integration process advocating choreographic programs as intermediate artifacts to refine high-level global specifications (e.g., UML Sequence Diagrams), defined by the domain experts of each partner, into concrete, distributed implementations. In ChIP, once the stakeholders agree upon a choreographic integration design, they can automatically generate the respective local connectors, which are guaranteed to faithfully implement the described distributed logic. In the paper, we illustrate ChIP with a pilot from the EU EIT Digital project SMAll, aimed at integrating pre-existing systems from government, university, and transport industry.

This paper describes the design, implementation and initial evaluation of an object-based Distributed Shared Memory (DSM) middleware system for Java. The resulting implementation allows the construction of event-based distributed systems using a simple programming model, allowing applications to be deployed without hardware or communication channel assumptions. Our implementation utilises standard, freely available, Message Oriented Middleware (MOM). This approach eases DSM development as many reliability and scalability issues associated to DSM may be handled by MOM. In addition to an implementation description, we provide performance results of a prototype system on a Local Area Network.

The Java Community Process (JCP) has recently finalized a Java Specification Request (JSR) to cope with location-awareness (JSR-179) in Connected Limited Device Configuration (CLDC). Implementations of this specification may rely on several location methods, including satellite based methods like GPS, as well as short-range positioning methods based on Received Signal Strength (RSS). Though RSS is a good location fingerprint for indoor positioning, no standard technique to tailor RSS-based approaches to the JSR-179 API has been proposed yet. In this paper we propose such a technique, and we evaluate its effectiveness through a Bluetooth-based prototype. Specifically, we show how to extend the Java APIs for Bluetooth (JSR-82) in order to provide the Location API with RSS-based position-information. Moreover, we show how to adapt RSS-based approaches to Location-API’s semantics. Our solution is based on the insertion of a specific component into the JSR-82 API. This is in charge of producing all the information needed to build Location objects as defined in the JSR-179. We evaluate the effectiveness of the approach by examining preliminary experimental results obtained from the first system prototype.

Explicit behavioural interface description languages (BIDLs, protocols) are now recognized as a mandatory feature of component languages in order to address component reuse, coordination, adaptation and verification issues. Such protocol languages often deal with synchronous communication. However, in the context of distributed systems, components communicating asynchronously through mailboxes are much more relevant. In this paper, we advocate for the use of Symbolic Transition Systems as a protocol language which may deal also with this kind of communication. We then present how this generic formalism, specialized with different mailbox protocols, may be used to address verification issues related to the component mailboxes.

Network infrastructures composed of wireless access points (e.g. IEEE 802.11 APs) connected via a LAN have been enabling a form of mobile computing known as Nomadic Computing (NC). In order to manage migrations of a mobile terminal among different wireless networks, such infrastructures are often decomposed in several domains: a domain can be a building floor, a building room, or a certain zone of a campus. Since the traditional middleware are unsuitable for mobile computing [1], during the past years a great deal of research has been conducted. Research efforts have been progressed along the following directions: i) providing mechanisms, such as context awareness, reconfiguration, spontaneous discovery; ii) dealing with QoS aspects such as security. While we recognize these studies as fundamental milestones for the pursuit of new middleware for mobile computing, most of them do not effectively explore how the distributed interaction (such as RPC or RMI) has to take place.

International audience; In distributed collaborative systems, replicated objects, shared by users, are subject to concurrency constraints. All methods [4, 13, 18, 15, 16, 19, 22] proposed to serialize concurrent operations and achieve copies convergence of replicated objects are based on the use of Operational Transformations. In this context, giving the user the ability to undo an operation has been recognized as a difficult problem [1, 2, 3, 12, 14, 20, 21]. The few general propositions to solve the problem sometimes compromise copies convergence and/or users’ intention, insofar as the Operational Transformations used are unsuitable for undo. This paper has a twofold objective. Firstly, it aims to highlight two general conditions (named C3 and C4) that need to be satisfied by any transformation adapted to undo. Secondly, it presents a general undo algorithm based on the definition of a generic undo-fitted transformation, which automatically verifies these conditions. The interest of the proposed method is that the undoing of an operation obeys to the same processing as the one used for regular operations in collaborative systems such as [15,19].