%0 Journal Article
%T Peer-to-Peer Multicasting Inspired by Huffman Coding
%A Bartosz Polaczyk
%A Piotr Cho£¿da
%A Andrzej Jajszczyk
%J Journal of Computer Networks and Communications
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/312376
%X Stringent QoS requirements of video streaming are not addressed by the delay characteristics of highly dynamic peer-to-peer (P2P) networks. To solve this problem, a novel locality-aware method for choosing optimal neighbors in live streaming multicast P2P overlays is presented in this paper. To create the appropriate multicast tree topology, a round-trip-time (RTT) value is used as a parameter distinguishing peers capabilities. The multicast tree construction is based on the Huffman source coding algorithm. First, a centrally managed version is presented, and then an effective use of a distributed paradigm is shown. Performance evaluation results prove that the proposed approach considerably improves the overlay efficiency from the viewpoint of end-users and content providers. Moreover, the proposed technique ensures a high level of resilience against gateway-link failures and adaptively reorganizes the overlay topology in case of dynamic, transient network fluctuations. 1. Introduction For previous few years peer-to-peer (P2P) related flows (overlay traffic) have represented a vast majority of the whole Internet traffic. Thus, P2P networking has become an important branch of today¡¯s telecommunications. It involves not only file-sharing (BitTorrent, Ares Galaxy, Gnutella), but also multimedia streaming (PPLive, SopCast), Internet telephony (Skype), anonymous routing (Tor), and many aspects of content distribution networks or cloud networking. With the increased interest in quality-requiring applications, the problem of the quality of service (QoS) assurance is a real challenge in P2P-based streaming. Live streaming transfers based on the P2P paradigm impose strict constraints on latency between a video server and peers (end-users). Since the requirements are not fully addressed by the characteristics of P2P networking, a considerable attention has been put on the overcoming techniques. One of the most basic parameters that highly influence the quality experienced by end-users is the effective downloading speed and its stability over time. A buffering process, observed by end-users as a transient interruption of content delivery, can be minimized, or even avoided, when oscillations of the downloading speed are small. To accomplish the gapless playback, the P2P application-layer links should be set over short distances with additional care about the available capacity. This task is a nontrivial problem as P2P systems were invented to be underlay-agnostic. In practice, they have not usually recognized proximity between the candidate peers nor estimate
%U http://www.hindawi.com/journals/jcnc/2013/312376/