Near-Far Effect on Coded Slotted ALOHA

International audienceMotivated by scenario requirements for 5G cellular networks, we study one of the candidate protocols for massive random access: the family of random access methods known as Coded Slotted ALOHA (CSA). A recent trend in research has explored aspects of such methods in various contexts, but one aspect has not been fully taken into account: the impact of path loss, which is a major design constraint in long-range wireless networks. In this article, we explore the behavior of CSA, by focusing on the path loss component correlated to the distance to the base station. Path loss provides opportunities for capture, improving the performance of CSA. We revise methods for estimating CSA behavior, provide bounds of performance, and then, focusing on the achievable throughput, we extensively explore the key parameters, and their associated gain (experimentally). Our results shed light on the behavior of the optimal distribution of repetitions in actual wireless networks

Adaptive Multiplicity Codes based PIR Protocol for Multi-Cloud Plateform Services

International audienceOur contribution consists in deriving an adaptive multiplicity code based PIR protocol based on a code selection algorithm which guarantees minimal communication overhead for a given system architecture. We formulate the related constrained optimization problem, analyze it and introduce an algorithm for enabling the adaptive Information Theoretical secure PIR protocol to operate in highly dynamic multi cloud platform services. In addition, we prove that this algorithm also solves the feasibility problem and achieves optimal solution

Reed Solomon Codes On Graph for DVB-SH Streaming Services

Abstract—Our study aims at bringing a software-based alternative for decoding Reed Solomon over the MPE-IFEC in the DVB-SH system, at the cost of a lower complexity and a good performance. The MPE-IFEC is operating in the Link layer, where the lost packets are considered as erasures. In this context, we propose to recover losses by decoding on a graph the binary image of the Reed Solomon code over a Binary Erasure Channel. Our approach is based on the recent advances in codes on graph theory, and reveals Maximum Likelihood performance. I