Déploiement À Grande Échelle De La Voix Sur IP Dans Des Environnements Hétérogènes Abdelbasset Trad

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Déploiement À Grande Échelle De La Voix Sur IP Dans Des Environnements Hétérogènes Abdelbasset Trad Déploiement à grande échelle de la voix sur IP dans des environnements hétérogènes Abdelbasset Trad To cite this version: Abdelbasset Trad. Déploiement à grande échelle de la voix sur IP dans des environnements hétérogènes. Networking and Internet Architecture [cs.NI]. Université de Nice Sophia Antipolis, 2006. English. tel-00406513 HAL Id: tel-00406513 https://tel.archives-ouvertes.fr/tel-00406513 Submitted on 22 Jul 2009 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UNIVERSITÉ DE NICE - SOPHIA ANTIPOLIS UFR SCIENCES École Doctorale STIC Sciences et Technologies de l’Information et de la Communication THÈSE DE DOCTORAT Présentée par Abdelbasset TRAD en vue de l’obtention du titre de DOCTEUR EN SCIENCES de l’Université de Nice - Sophia Antipolis Spécialité : INFORMATIQUE Sujet de la thèse: Déploiement à Grande Échelle de la Voix sur IP dans des Environnements Hétérogènes Large Scale VoIP Deployment over Heterogeneous Environments Laboratoire d’Accueil : INRIA Sophia-Antipolis Projet de Recherche : Planète Soutenue publiquement à l’INRIA le 21 Juin 2006 à 14h00 devant le jury composé de: M. Jean-Paul Rigault UNSA/INRIA Président M. Hossam Afifi INT Evry/INRIA Dir. de thèse Mme Houda Labiod ENST Paris Rapporteur M. Pascal Lorenz Université de Haute Alsace Rapporteur M. Tijani Chahed INT Evry Examinateur M. Ken Chen Université de Paris 13 Examinateur À mes grands-parents À mes parents À mon frère et à mes soeurs Remerciements Je voudrais remercier Mme Houda Labiod, Maître de conferences à l’ENST Paris et M. Pascal Lorenz, Professeur à l’Université de Haute Alsace, qui m’ont fait l’honneur d’avoir accepté d’être les rapporteurs de ma thèse. Je remercie également M. Jean-Paul Rigault, Professeur à l’Université de Nice - Sophia Antipolis, qui m’a fait l’honneur de présider mon jury de thèse. Je tiens aussi à remercier M. Tijani Chahed, Maître de conferences à l’INT Evry et M. Ken Chen, Professeur à l’Université de Paris 13, d’avoir bien voulu participer à ce jury. Leur déplacement pour ma soutenance était pour moi un grand honneur et un vrai plaisir. Je tiens à exprimer mes remerciements les plus vifs à M. Hossam Afifi, Professeur à l’INT Evry, qui m’a encadré durant mon stage de fin d’études d’Ingénieur, mon stage de DEA et ma thèse de doctorat, j’ai appris de lui toute une philosophie de travail dans le domaine de la recherche scientifique. La liberté et la confiance qu’il m’a accordées ont beaucoup contribué au developpement de mon autonomie dans le travail. Malgré qu’il n’était pas toujours près de moi, il m’a apporté lors de ses visites à l’INRIA Sophia Antipolis des conseils judicieux, des encouragements, un soutien moral, beaucoup de sympathie et de bonne humeur. J’exprime mes remerciements et ma gratitude à M. Walid Dabbous, Directeur de Recherche et chef du projet Planète de l’INRIA Sophia Antipolis, pour la confiance et l’occasion qu’il m’a accordées afin de faire une grande partie de ma formation en recherche scientifique au sein du projet Planète. Les années que j’ai passées à Planète m’ont permis d’acquérir une expérience précieuse aussi bien sur le plan professionnel que sur le plan humain. Merci individuellement à mes collègues de l’équipe Planète pour leur sympathie et pour l’ambiance amicale qui règne au sein du projet. Un grand merci à M. Denis Caromel de m’avoir permis de concrétiser ma passion pour l’enseignement en donnant le cours “Multimedia sur l’Internet” pour les étudiants du Mastère Télécommunications de l’Université de Nice Sophia Antipolis, cette expérience d’enseignement était très enrichissante au niveau pédagogique et scientifique. Je dois pas oublier de remercier tous mes enseignants depuis l’école pri- maire, c’est eux qui ont éveillé en moi mon amour et ma passion pour la science et pour le savoir. Sans doute je vais pas trouver les mots pour remercier les personnes qui me sont les plus chères: mes parents, pour leur sacrifices, leur patience, et tous ce qu’ils ont fait pour m’apporter le bonheur. Enfin, je tiens à remercier tous mes amis et tous ceux et qui m’ont soutenu surtout pendant les moments délicats, en particulier les membres de ma petite famille qui m’ont accompagné par la pensée tout au long de cette thèse. J’ai également une pensée toute particulière pour mon grand-père décédé cette année. Par son exemple et ses valeures, il a contribué à sa façon à l’aboutissement de ce travail que je lui dédie aujourd’hui. Abdelbasset Trad Sophia Antipolis, France. i DÉPLOIEMENT À GRANDE ÉCHELLE DE LA VOIX SUR IP DANS DES ENVIRONNEMENTS HÉTÉROGÈNES RÉSUMÉ Dans cette thèse, nous nous intéressons au déploiement à grande échelle de la Voix sur IP (VoIP) dans des environnements Internet hétérogènes. Après une description des mécanismes de codage et de transmission de la voix sur l’Internet, nous étudions dans une première partie de la thèse, les limites de performance dans le cas d’une transmission d’un grand nombre de flux de voix sur IP entre deux passerelles téléphoniques. Nous discutons le besoin d’utilisation de mécanismes de con- trôle de congestion pour le trafic de voix sur IP qui est en croissance continue sur l’Internet. Nous proposons un nouveau schéma de contrôle de congestion de la voix sur IP. Ce schéma combine le multiplexage de flux RTP et le mécanisme de contrôle TCP-amical (TCP-friendly) afin d’améliorer l’efficacité et la performance de la transmission des flux de voix sur IP et de garantir l’équité avec les autres types de trafic coexistant sur l’Internet. La deuxième partie de la thèse est consacrée à l’étude de la transmission de la voix dans des environnements de réseaux locaux sans-fil IEEE 802.11e. Nous développons un modèle analytique permettant d’évaluer la capacité d’un réseau 802.11e en nombre de communications de voix sur IP en fonction des paramètres du niveau appli- catif (codage audio utilisé) ainsi que des paramètres relatifs aux canal de transmission sans-fil. Ce modèle peut être utilisé pour ajuster ces paramètres afin d’augmenter la capacité du réseau sans-fil tout en considérant les contraintes strictes des communications intéractives de la voix sur IP. Dans la dernière partie de la thèse, nous étudions le cas de la transmission de la voix sur IP dans des environnements Internet hétérogènes (filaires/sans-fil) constitués en partie par des liens d’accès sans-fil. Nous proposons une architecture basée sur une passerelle de voix sur IP placée au bord du réseau sans-fil. Cette passerelle est utilisée pour adapter les flux de voix aux caractéristiques du réseau sans-fil. Le mécanisme d’adaptation proposé estime dynamiquement l’état de congestion du canal sans-fil et permet la différentiation entre les pertes de paquets causées par la congestion et celles dûes aux erreurs de transmission sur le canal sans-fil. L’adaptation appropriée est alors appliquée. Le mécanisme d’adaptation proposé, ne nécessite pas de modifications du protocole de contrôle d’accès au canal sans-fil (MAC), ce qui facilite son déploiement sur l’infrastructure réseau existante. MOTS CLÉS Voix sur IP, déploiement à grande échelle, codecs audio, contrôle de congestion adaptatif, multi- plexage de flux, contrôle TCP-amical, réseaux IEEE 802.11e, capacité réseau, E-Model. iii LARGE SCALE VOIP DEPLOYMENT OVER HETEROGENEOUS ENVIRONMENTS ABSTRACT In this thesis, we focus on large scale Voice over IP (VoIP) deployment over heterogeneous Internet environments. We first present an overview of VoIP coding and transmission mechanisms. Then, we investigate performance limitations in the case of a large number of VoIP flows transported over wired Internet links between peer VoIP gateways. We address, in the first part of the thesis, the need to design congestion control for the growing class of VoIP traffic and we propose a novel VoIP con- gestion control scheme. This scheme combines RTP voice flow multiplexing and the TCP-friendly congestion control mechanism in order to improve VoIP transmission efficiency and performance while being fair with coexisting Internet traffic. The second part of this thesis deals with VoIP trans- mission over IEEE 802.11e wireless LAN environments (WLAN). We develop an analytical model to evaluate the capacity of an 802.11e network in terms of VoIP communications while condition- ing on the used audio codec and MAC/PHY parameters. This model can be applied to tune IEEE 802.11e standard parameters in order to increase the WLAN capacity while considering stringent requirements of interactive VoIP communications. In the last part of this thesis we study the case of VoIP transmission over heterogeneous Internet environments where WLAN represents the last- hop Internet access link. We propose an architecture that is based on a VoIP gateway located at the edge of the wired and the wireless network, and used to adapt voice flows according to wire- less network characteristics. The proposed adaptation mechanism dynamically estimates wireless channel congestion state and allows the differentiation between congestion loss and loss caused by wireless channel transmission errors. Then, the appropriate adaptation is applied. Specifically, in our proposed adaptive mechanism, the medium-access control (MAC) protocol at the wireless end stations does not need to be modified, making the mechanism more readily deployable over the existing network infrastructure.
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