Adaptive Packet Video Streaming Over P2P Networks Using Active Measurements Mubashar Mushtaq and Toufik Ahmed LaBRI – University of Bordeaux 1 351, cours de la Libération 33405 Talence Cedex FRANCE {mushtaq, tad}@labri.fr Abstract In this paper we consider the problem of real-time streaming of IP packet video over Peer-to-Peer networks (P2P) from multiple senders to a single receiver. P2P networks are characterized by a potentially large and highly dynamic population of hosts that join and leave the network frequently. We present the design and evaluation of a quality adaptation streaming mechanism in a multi-source streaming to a single receiver. Multimedia streaming is a real time application so, the main challenges in the design of this mechanism are (1) selection of senders peers nodes; (2) stream switching among the peers; (3) optimizing video quality by active measurements of links; and (4) enhancing the overall Quality of Service (QoS). Our key technique to provide quality adaptation is based on active measurements of network links and selection of sender peers to enhance the overall throughput. We used video traffic organized as MDC (Multiple Description Coding) layers, which provides high error resilient. Our simulations results using ns2 show that our solution allows to efficiently utilize available network bandwidth of sending peers and allow maximizing streaming qualities at the reception peer. Keywords: Peer to Peer streaming, Video Streaming, QoS, Quality Adaptation, Active Measurement. 1. Introduction Content sharing between communities has revolutionized the Internet. During the last few years, we lived a new phenomenon that changed the Internet business model especially for ISP (Internet Service Provider). Peer-to-Peer (P2P) systems have gained tremendous intentions during these years. The Peer-to- Peer (P2P) phenomenon is facilitating information flow from and back to the end users. Unlike traditional distributed systems based on pure client/server model, P2P networks are self organizing networks that aggregate large amount of heterogeneous computers called nodes or peers (nodes and peers are used interchangeably in this paper). In P2P systems, peers can communicate directly with each other for the sharing and exchanging of data, besides this data exchange these peer nodes also share their communication and storage resources. The characteristics of P2P systems make them a better choice for multimedia content sharing/streaming over IP networks. P2P systems are dynamic in nature where nodes can join and leave the network frequently and that might not have a permanent IP addresses and observe dynamic changes over the inter connection links. Virtual networks are built on the top of these networks at the application level in which individual peers communicate with each other and share both communication and storage resources, ideally directly without using a dedicated server. The main concept of P2P networking is that each peer is a client and a server at the same time. P2P media sharing uses two basic concepts. In the ‘open- after-downloading’ mode, the media content is played after downloading all the contents of the file from different participants, while the ‘play-while- downloading’ mode allows playing while downloading the content, which is commonly known as streaming. The ‘play-while-downloading’ has many advantages over ‘open-after-downloading’ as it requires lesser memory and client is not expected to wait for longer time to finish download first. In this paper, we consider the problem of Peer-to-Peer streaming defined as a content streaming from multiple senders Proceedings of the 11th IEEE Symposium on Computers and Communications (ISCC'06) 0-7695-2588-1/06 $20.00 © 2006 IEEE