VSP (video servis sağlayıcıları) tarafından yönetilen DASH (dinamik adaptif iletim) video servisleri

Dynamic adaptive streaming over HTTP (DASH) clients compete with each other over one or more bottleneck links in a network, which results in fluctuations in TCP throughput and QoE, QoE unfairness among clients, and under utilization of the network capacity. We propose both centralized and distributed architectures for collaboration between network service provider (NSP), video service provider (VSP), and users (DASH clients) to provide DASH service over software-defined networks (SDN) with quality-of-service (QoS) reserved network slices. We show that QoS reservation alone is not sufficient to overcome QoE fluctuations per client and unfairness between clients, and clients also need to employ TCP receive window adaptation knowing their fair-share bitrate. To this effect, we propose two collaboration architectures to inform clients about their fair-share bitrates. We first present a centralized collaboration architecture between the NSP, VSP, and the users, where VSP assigns a fair-share bitrate to each DASH client. We then present a distributed collaboration architecture, where a group of DASH clients sharing a reserved network slice collaborate among themselves. The collaboration groups are identified by the VSP using information provided by the NSP, and we propose a protocol that allows clients within a group to share critical parameters with each other so that each client can estimate its fair-share bitrate in a distributed manner. We show that collaboration rather than competition between clients also improves utilization of the reserved capacity in addition to avoiding throughput fluctuations and achieving a smooth QoE. Experimental results demonstrate the superior performance of both types of collaboration over competition between the clients.