41,979 research outputs found
Portability, compatibility and reuse of MAC protocols across different IoT radio platforms
To cope with the diversity of Internet of Things (loT) requirements, a large number of Medium Access Control (MAC) protocols have been proposed in scientific literature, many of which are designed for specific application domains. However, for most of these MAC protocols, no multi-platform software implementation is available. In fact, the path from conceptual MAC protocol proposed in theoretical papers, towards an actual working implementation is rife with pitfalls. (i) A first problem is the timing bugs, frequently encountered in MAC implementations. (ii) Furthermore, once implemented, many MAC protocols are strongly optimized for specific hardware, thereby limiting the potential of software reuse or modifications. (iii) Finally, in real-life conditions, the performance of the MAC protocol varies strongly depending on the actual underlying radio chip. As a result, the same MAC protocol implementation acts differently per platform, resulting in unpredictable/asymmetrical behavior when multiple platforms are combined in the same network. This paper describes in detail the challenges related to multi-platform MAC development, and experimentally quantifies how the above issues impact the MAC protocol performance when running MAC protocols on multiple radio chips. Finally, an overall methodology is proposed to avoid the previously mentioned cross-platform compatibility issues. (C) 2018 Elsevier B.V. All rights reserved
Separation Framework: An Enabler for Cooperative and D2D Communication for Future 5G Networks
Soaring capacity and coverage demands dictate that future cellular networks
need to soon migrate towards ultra-dense networks. However, network
densification comes with a host of challenges that include compromised energy
efficiency, complex interference management, cumbersome mobility management,
burdensome signaling overheads and higher backhaul costs. Interestingly, most
of the problems, that beleaguer network densification, stem from legacy
networks' one common feature i.e., tight coupling between the control and data
planes regardless of their degree of heterogeneity and cell density.
Consequently, in wake of 5G, control and data planes separation architecture
(SARC) has recently been conceived as a promising paradigm that has potential
to address most of aforementioned challenges. In this article, we review
various proposals that have been presented in literature so far to enable SARC.
More specifically, we analyze how and to what degree various SARC proposals
address the four main challenges in network densification namely: energy
efficiency, system level capacity maximization, interference management and
mobility management. We then focus on two salient features of future cellular
networks that have not yet been adapted in legacy networks at wide scale and
thus remain a hallmark of 5G, i.e., coordinated multipoint (CoMP), and
device-to-device (D2D) communications. After providing necessary background on
CoMP and D2D, we analyze how SARC can particularly act as a major enabler for
CoMP and D2D in context of 5G. This article thus serves as both a tutorial as
well as an up to date survey on SARC, CoMP and D2D. Most importantly, the
article provides an extensive outlook of challenges and opportunities that lie
at the crossroads of these three mutually entangled emerging technologies.Comment: 28 pages, 11 figures, IEEE Communications Surveys & Tutorials 201
Can Component/Service-Based Systems Be Proved Correct?
Component-oriented and service-oriented approaches have gained a strong
enthusiasm in industries and academia with a particular interest for
service-oriented approaches. A component is a software entity with given
functionalities, made available by a provider, and used to build other
application within which it is integrated. The service concept and its use in
web-based application development have a huge impact on reuse practices.
Accordingly a considerable part of software architectures is influenced; these
architectures are moving towards service-oriented architectures. Therefore
applications (re)use services that are available elsewhere and many
applications interact, without knowing each other, using services available via
service servers and their published interfaces and functionalities. Industries
propose, through various consortium, languages, technologies and standards.
More academic works are also undertaken concerning semantics and formalisation
of components and service-based systems. We consider here both streams of works
in order to raise research concerns that will help in building quality
software. Are there new challenging problems with respect to service-based
software construction? Besides, what are the links and the advances compared to
distributed systems?Comment: 16 page
Threads and Or-Parallelism Unified
One of the main advantages of Logic Programming (LP) is that it provides an
excellent framework for the parallel execution of programs. In this work we
investigate novel techniques to efficiently exploit parallelism from real-world
applications in low cost multi-core architectures. To achieve these goals, we
revive and redesign the YapOr system to exploit or-parallelism based on a
multi-threaded implementation. Our new approach takes full advantage of the
state-of-the-art fast and optimized YAP Prolog engine and shares the underlying
execution environment, scheduler and most of the data structures used to
support YapOr's model. Initial experiments with our new approach consistently
achieve almost linear speedups for most of the applications, proving itself as
a good alternative for exploiting implicit parallelism in the currently
available low cost multi-core architectures.Comment: 17 pages, 21 figures, International Conference on Logic Programming
(ICLP 2010
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