Competitive Assessments for HAP Delivery of Mobile Services in Emerging Countries

In recent years, network deployment based on High Altitude Platforms (HAPs) has gained momentum through several initiatives where air vehicles and telecommunications payloads have been adapted and refined, resulting in more efficient and less expensive platforms. In this paper, we study HAP as an alternative or complementary fast-evolving technology to provide mobile services in rural areas of emerging countries, where business models need to be carefully tailored to the reality of their related markets. In these large areas with low user density, mobile services uptake is likely to be slowed by a service profitability which is in turn limited by a relatively low average revenue per user. Through three architectures enabling different business roles and using different terrestrial, HAP and satellite backhaul solutions, we devise how to use in an efficient and profitable fashion these multi-purpose aerial platforms, in complement to existing access and backhauling satellite or terrestrial technologies

SOS: An Object-Oriented Operating System ―- Assessment and Perspectives

International audienceSOS (SOMIW Operating System) is the result of a four-year effort at INRIA to define an object-oriented operating system. SOS provides support for arbitrary, user-defrned, typed objects. The system implements object migration; this mechanism is generic, but can be tailored to specific object semantics thanks to the prerequisite and upcall concepts. SOS also supports Fragmented Objects (FOs), i.e. objects the representation of which spreads across multiple address spaces. Fragments of a single FO are objects that enjoy mutual communication privileges. A fragment acts as a proxy, i.e. a local interface to the FO. All the other mechanisms of SOS are built upon these basic abstractions. Thanks to prerequisites, migration of data may cause the migration and dynamic type-checking and linking of the corresponding code. A distributed object manager, an object storage service, a naming service, as well as a protocol toolbox and some applications, have been built as FOs. This paper gives a detailed account of the architecture and design decisions of the SOS prototype on UNIX. rùy'e examine both good decisions and problems. The basic good decision is our simple object model, and its ability to map user-defrned semantics (policy decisions) on system-implemented mechanisms. The most important problem is the dynamic nature of Fragmented Objects, and inadequate support for them

An Object-Oriented Approach for Replication Management

One of the main goals of the object-oriented approach issoftware reuse. Research in replication management brings forward many algorithms that often need reinventing the wheel to progress. Our approach consists of providing high-level building blocks for various replication protocols, eachonepaying only for the mechanisms it uses. Our goal is to encourage reusability of distributed abstractions in replication management

FOG/C++: a Fragmented-Object Generator

International audienceWe describe a language and a compiler for writing distributed applications and systems, structured with fragmented objects. The language is an extension of C++. The compiler statically ensures the encapsulation of fragmented objects, the type-safety of remote communication, and generates code for the common cases of remote communication and object migration. It interfaces to the SOS operating system via a set of predefined classes, which are easily portable to other operating system

BOAR: A Library of Fragmented Object Types for Distributed Abstractions

International audienceWe present BOAR, a forest-structured library of predefined Fragmented Objects (FOs) encapsulating commonly used distributed abstractions. We identify three kinds of interaction FO types (channel, sharing, and synchronization), which can be beneficially included in BOAR. A channel FO type encapsulates a remote or group invocation protocol. A sharing FO type encapsulates a sharing mechanisms such as replication or partition. Finally, a synchronization FO type encapsulates a synchronization mechanism. A FO programmer picks-up from BOAR, the FO types implementing the mechanisms which fits best its need

A Study on Simple Geometries for Modeling User Equipment Geospatial Attachment to Mobile Cells

As data-driven solutions will become an important component of next-generation networks, we were faced with the difficulty of developing cross-domain datasets for training machine learning models. In order to understand how external sources of data should be associated with mobile network data at cell level, we have derived a method for splitting simple geometric coverage models for base stations to obtain coverage models for sectorized cells. Then, we developed a method to compare the coverage models with a ground truth of real measurements. We also proposed to use the notions of convex and concave hulls to quantify when a geometry is undersized or oversized. The two types of geometry that were evaluated were the Voronoi polygons and circular shapes, with sector split. All frequency bands considered, the results have shown that Voronoi sector split model combined with upscaling the coverage shapes was the closest to the ground truth, with an average recall of 0.74. Since upscaling Voronoi polygons should be a good practice to improve coverage modelling, we have also proposed an approach using more affordable data (i.e. cell level aggregates) instead of user locations to find the best scaling factor. All frequencies combined, we have observed an average increase of 0.13 points in the recall between the diagram with the default scale and the scale-tuned diagram

Cell selection game in heterogeneous macro-small cell networks

International audienceHeterogeneous networks (HetNets) which include macrocells with short range small cells proved a better coverage and higher user data rates compared to classical networks. Using the same spectrum as the macrocells, small cells would allow increased spatial reuse of bandwidth. In industrialized countries, the deployment of new small cells by another actor (tier) to cover the outage improves the service with a lower cost. In this paper, we investigate cell association issue in heterogeneous networks composed of small and macrocells operating in the same spectrum. In contrast to the related work, we consider that the small cells are a cellular network belonging to another tier. Hence, there is competitiveness between the two tiers in order to selfishly maximize the gain while respecting the User Equipment (UE) Quality of Service (QoS) requirements. We propose a model based on game theory in order to get the best distribution of user equipments among small and macro base stations