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Making cities smarter is the future. By bringing more technology into existing city infrastructure, smart city applications can arise. Whether these applications track devices e.g. public lightning, environmental measurements e.g. temperature or air quality, or analyze video streams e.g. for people density, it is expected that these will require a (near-) real time data connection. Upcoming 5G networks will be able to handle large amounts of connections at high speeds and low latencies and will therefor outperform current technologies such as 4G and low-power wide-area networks. In order to do so, these 5G networks fall back to numerous fiber connected small cells for up & downlink to the Internet. In this publication, we are looking into the additional fiber equipment and deployment cost to connect the required smart city network infrastructure, taking into account a Fiber-to-the-Home (FTTH) network is already available or will be installed as part of the smart city network rollout. More concretely, we are proposing a methodology comparing an anticipated and incremental planning approach for a number of different extensions upon the FTTH-network: connecting all electrical cabinets, connecting public lightning, and the connection of 5G using small cells. From this, we want to learn how much the total rollout cost can be reduced using a future-oriented smart city approach taking into account all future extensions, compared to an incremental short-time planning only planning additional fiber when required. In the meantime, we want to show the additional cost of creating a smart city network is limited when it is being combined with a FTTH rollout. Results of the proposed methodology and use case will be modeled planning and design software Comsof Fiber and will be published in a future work.

In this paper, different optical ring architectures are considered and the optical add/drop multiplexer (OADM) functional architecture is described. In addition, different aspects of ring network design and their impact on the network architecture are discussed.

The two-volume set LNCS 7044 and 7045 constitutes the refereed proceedings of three confederated international conferences: Cooperative Information Systems (CoopIS 2011), Distributed Objects and Applications - Secure Virtual Infrastructures (DOA-SVI 2011), and Ontologies, DataBases and Applications of SEmantics (ODBASE 2011) held as part of OTM 2011 in October 2011 in Hersonissos on the island of Crete, Greece. The 55 revised full papers presented were carefully reviewed and selected from a total of 141 submissions. The 27 papers included in the first volume constitute the proceedings of CoopIS 2011 and are organized in topical sections on business process repositories, business process compliance and risk management, service orchestration and workflows, intelligent information systems and distributed agent systems, emerging trends in business process support, techniques for building cooperative information systems, security and privacy in collaborative applications, and data and information management.

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.

The introduction of FTTH leads to high costs, especially in fiber deployment. In operations we face a high complexity and corresponding high cost of fiber splicing compared to copper welding. However, fiber based access networks are less vulnerable to degradation because of outside plant conditions, leading to lower failure rates. In order to correctly calculate the business case for a new FTTH network deployment, the capital expenditures need to be balanced with the expected gains in operational expenditures compared to the current (e.g. copper based) access network. In this paper we present a hierarchical approach for getting a clear and balanced view on the costs of an FTTH deployment. This includes a gradual increasing level of detail and a clear view on the trade-offs in each step, an integrated calculation model containing both CapEx and OpEx and the interaction between both. We focus on the modeling of the network maintenance (preventive repair) and repair process and highlight the key differentiators between the copper and the fiber based case.

When introducing a new telecom service it is very important for the operator to set the tariff right. Being too prudent by setting the tariff too high will most probably put the operator out of competition. On the other hand, setting the tariff too low might skim profits, lead to cannibalization of other services, forcing the operator to raise the tariffs - which clearly has a negative impact on the user satisfaction and coupled market share. Current telecom networks make progressively use of an all IP network, in which all services run over the same infrastructure. While this move allows reducing costs due to economies of scale and scope, it disguises the costs of each of the different services within the full costs of the network. As the tariff is expected to be sustainable in the long run, the costs associated to the roll-out of the new service should at least be covered by the (forecasted) revenues. Different allocation schemes can be used for discovering the costs associated to each of the services over the network, and their use leads to a better understanding of the margins on sustainable tariffs as opposed to stand alone or break even calculations. The whole calculation is largely dependent on the forecasts of adoption, bandwidth growth and cost evolution. Within this paper we will first investigate the sensitivity of the calculated tariff margins on changes of these inputs. In a second phase we will investigate what impact the calculated tariff margin might have on the adoption of the service. We also indicate that there are important changes to these margins when quantifying this impact and using iterative calculations.

In this paper, the method of Garabedian is applied to finite difference equations derived from the elliptic diffusion operator ?D Δ +? over rectangular and triangular nets. An example is given for which GARABEDIAN'S method yields a useless result.

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.

Nowadays the World Wide Web has become the most important platform for publishing scientific materials. The first advantages of online publication are instant access and easy, low-cost, distribution and duplication. But of great impact in middle term success of electronic publication is the availability of systems that support citation and metrics to evaluate the performances of the different actors in the scientific sector. EPICA is an new infrastructure technology supporting integration of uniform and persistent naming systems and declarative expression of metrics used to asses performances. This way independent actors are allowed to cooperate in a common infrastructure. The key element to support this integration is the semantic mapping between metrics and scientific publications available in the Web. This paper discusses this vision and proposes preliminary results related to the definition of a Metrics Assessment Data Model to express this semantic mapping.

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.

There is an increasing demand for realizing communication services for nomadic environments, capable to provide applications with mobility management facilities and application-aware adaptation support. This paper proposes a novel mobility management and communication architecture specifically suited for nomadic environments, offering communication facilities and adaptation support by means of an API, named NCSOCKS. The driving idea is to provide application and middleware developers of nomadic services with essential mobility-enabled communication support, while hiding network heterogeneity in terms of wireless technology and leveraging the availability level of communication in spite of transient signal degradations. Transient signal degradations, due to device movements and/or shadowing, have the effect of increasing the handoff frequency. The proposed architecture integrates a novel mechanism to improve the connection availability by reducing the number of unnecessary handover procedures. In order to evaluate the proposal, an approach based on combined use of simulation and prototype-based measurements is adopted.

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].

International audience; Asynchronous communications are prominent in distributed and mobile systems. Often concurrent systems consider an abstract point of view with synchronous communications. However it seems more realistic and finer to consider asynchronous communicating systems, since it provides a more primitive communication protocol and maximize the concurrency. Several languages and models have been defined using this communication mode: agent, actor, mobile computation, and so on. Here we reconsider a previous component model with full data types and synchronous communications with an asynchronous flavour. The dynamic behaviour of a component is represented as a structured symbolic transition system with mailboxes. We also present an algorithm devoted to an analysis of the dynamic behaviour of the system. This algorithm decides if the system has bound mailboxes and computes the reachable mailbox contents of the system. The component model and the algorithm are illustrated on a flight system reservation.

18 pages; International audience; Awareness has now become a widely accepted central feature in groupware systems. In this context, providing an awareness support consists in delivering to users involved in a collaborative task, information concerning their group, other users, their past, present or future roles or activities, etc. However, one of the potential underlying risks of such a support is to produce too much information. As a matter of fact, this amount of information may reveal itself cumbersome, leading to a cognitive overload for users which slows down the global activity of the group. In this paper, we propose to address this issue by stratifying the awareness information space into different levels of details. Such stratifications give users a progressive access to information: first, they can access to the most relevant information linked to their current activity and profile, and then, they can gradually access to the rest of awareness information. The proposed architecture relies on a generic Data Model for Awareness Information (DMAI) and on a Progressive Access Model (PAM), we have previously designed in the context of Web-based Information Systems. We show, on an example, how the coupling between the DMAI and the PAM allows groupware systems designers to describe a progressive access to awareness information. The defined stratifications can also be used as filters which save a given user, involved in a given role and performing a given activity, from useless, irrelevant or forbidden information.