Traffic and resource management in content-centric networks (design and evaluation)

Dans les dernières années, l utilisation d Internet a sensiblement changé en passant d un modèle de communication centré sur les machines á un centré sur les contenus. La plus part de services utilisés par les clients d Internet aujourd hui sont déjà centré sur les contenus même et pas sur leurs emplacement. Dans ce contexte, beaucoup de projets de recherche proposent un changement de l architecture de l Internet, en mettent des contenu identifié par leur nom au centre du réseau. Ce group de proposition est identifiés sous le nom de Information Centric Networking (ICN). Cette thèse se focalise sur la proposition Content-Centric Network (CCN). Dans une premier temps, nous analysons les performance du modèle de communication CCN en se concentrent sur le partage de la bande passante et de la mémoire et en proposant des formules pour la caractérisation du temps de transfert. Deuxièmement, nous proposons un protocole de contrôle de congestion et des mécanismes de forwarding pour CCN. En particulier on présent un premier mécanisme de contrôle de congestion, Interest Control Protocol (ICP), qui utilise une fenêtre contrôlé avec le mécanisme Additive Increase Multiplicative Decrease au récepteur. En complément avec ça, nous présentons un mécanisme distribué (hop-by-hop) pour obtenir une détection/réaction à la congestion plus rapide. Nous proposons aussi une modification d'ICP en implémentant le mécanisme Remote Adaptive Active Queue Management pour exploiter efficacement le multi-chemin. En fin, nous présentons un mécanisme de forwarding distribué qui base ses décisions sur des mesure de qualité d interface par chaque préfixe disponible dans les tableaux de routage.The advent of the World Wide Web has radically changed Internet usage from host-to-host to service access and data retrieval. The majority of services used by Internet s clients are content-centric (e.g. web). However, the original Internet revolves around host-to-host communication for which it was conceived. Even if Internet has been able to address the challenges offered by new applications, there is an evident mismatch between the architecture and its current usage. Many projects in national research agencies propose to redesign the Internet architecture around named data. Such research efforts are identified under the name of Information Centric Networking. This thesis focuses on the Content-Centric Networking (CCN) proposition. We first analyze the CCN communication model with particular focus on the bandwidth and storage sharing performance, We compute closed formulas for data delivery time, that we use in the second part of the thesis as guideline for network protocol design. Second, we propose some CCN congestion control and forwarding mechanisms. We present a first window based receiver driven flow control protocol, Interest Control Protocol (ICP). We also introduce a hop-by-hop congestion control mechanism to obtain early congestion detection and reaction. We then extend the original ICP congestion control protocol implementing a Remote Adaptive Active Queue Management mechanism in order to efficiently exploit heterogeneous (joint/disjoint) network paths. Finally, we introduce a distributed forwarding mechanism that bases its decisions on per prefix and per interface quality measurement without impacting the system scalability.PARIS-Télécom ParisTech (751132302) / SudocSudocFranceF

Active queue management for LTE uplink in eNodeB

Long-Term Evolution (LTE) is an evolved radio access technology of the 3rd generation mobile communication. It provides high peak bit rates and good end-to-end Quality of Service (QoS). Nevertheless, the wireless link is still likely to be the bottleneck of an end-to-end connection. Thus, having a sophisticated method to manage the queues of the mobile terminal is important. For Wideband Code Division Multiple Access (WCDMA), an Active Queue Management (AQM) algorithm managing the buffer based on the queue size was proposed. In LTE, due to its largely varying bit rates, the queue-size-based approaches are not suitable anymore. Thus, earlier studies have proposed a delay-based AQM to provide a better performance in LTE. For LTE uplink, the existing algorithm is supposed to be implemented in the User Equipment (UE). On the other hand, the implementation of an AQM in the UE is not mandatory. Until now, only a quite simple delay-.based queue management method called Packet Data Convergence Protocol (PDCP) discard is standardized by 3GPP. However, this method is not adaptive and cannot thus guarantee a good throughput. The purpose of this thesis is to develop an AQM method for LTE uplink to enhance the performance of TCP traffic. In order to have a better control of the LTE uplink traffic from the network side, the AQM algorithm is proposed to be implemented in the eNodeB. It retains the delay-based approach; to achieve it, a method is developed to estimate the queuing delays of the UE from the eNodeB side. The delay estimation is based on the changes in Buffer Status Reports (BSRs) and the amount of data delivered in the eNodeB. In LTE, BSRs are created and transmitted by the UE to report the queue length waiting for uplink transmission. A number of simulations are done to study the performance of the delay estimation and the resulting AQM algorithm. The new AQM algorithm is also compared with other algorithms, i.e. delay-based AQM implemented in the UE, PDCP discard and drop-from-front. The results show that the delay-based algorithm implemented in the eNodeB performs almost as well as when implemented in the UE. The results also show that the advantaged of delay-based algorithms comparing to the drop-from-front and PDCP discard are evident; they maintain a high throughput and the low end-to-end delay in most of the scenarios