Minecraft is a popular game with more than 20 million paying users and many more playing the free version. However, in multiplayer mode, only a few thousand users can play together. Our measurements show that, even reducing the landscape, i.e., the map, to a uniform flat land, a server cannot host significantly more users.For a common use case, when players cannot modify the map, we have designed and implemented Manycraft, an architecture to scale the number of users. Minecraft protocol messages are of three kinds: control, entity and map. In our approach, Kiwano, a distributed infrastructure for scaling virtual worlds, takes care of the entity related messages while the others are processed by a Minecraft server assigned to the player.

In today's virtual worlds, even in the massively multi-player games, the number of avatars together in a virtual place barely reaches thousands. Regarding the billions of users dwelling the web, this is astonishingly low. In this paper we identify spatial indexation as the bottleneck that impedes scalability and we propose Kiwano, a distributed system to scale up to millions and more. In order to split the load, Kiwano dynamically divides the space in zones, each having a server maintaining a spatial index of all moving objects within the zone. This allows to timely compute which objects are in the neighborhood of any avatar. Thus, knowing its immediate environment, the client is able compute the local scene.

Internet of Things (IoT) applications, systems and services are subject to law. We argue that for the IoT to develop lawfully, there must be technical mechanisms that allow the enforcement of specified policy, such that systems align with legal realities. The audit of policy enforcement must assist the apportionment of liability, demonstrate compliance with regulation, and indicate whether policy correctly captures legal responsibilities. As both systems and obligations evolve dynamically, this cycle must be continuously maintained. This poses a huge challenge given the global scale of the IoT vision. The IoT entails dynamically creating new services through managed and flexible data exchange. Data management is complex in this dynamic environment, given the need to both control and share information, often across federated domains of administration. We see middleware playing a key role in managing the IoT. Our vision is for a middleware-enforced, unified policy model that applies end-to-end, throughout the IoT. This is because policy cannot be bound to things, applications, or administrative domains, since functionality is the result of composition, with dynamically formed chains of data flows. We have investigated the use of Information Flow Control (IFC) to manage and audit data flows in cloud computing; a domain where trust can be well-founded, regulations are more mature and associated responsibilities clearer. We feel that IFC has great potential in the broader IoT context. However, the sheer scale and the dynamic, federated nature of the IoT pose a number of significant research challenges.

Abstract. By using the PLM (Product Lifecycle Management) principle on the formwork case study, after determining the functions and the technical solutions, the application must be made as optimum as possible in order to assure productivity and provide the necessary information as quick as possible. The concept is to create a complex management for the formwork based on augmented reality. By taking into account the development rate of the information, augmented reality is tending to be one of the widest (in term of domain) visualization instrument. Also used in the construction domain, augmented reality can be applied also for the case of formwork design and management. The application of the solution will be retrieved in the construction of the product, its transportation and deposit. The usage of this concept will help reduce, even eliminate human or technical errors and can offer a precise state of a specific required formwork from the stock.

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