Resilient Video Streaming with Path Diversity For Heterogeneous Networks Divyashikha Sethia Department of Computer Science Indian Institute of Technology (IIT), New Delhi, India. (91) 935-017-1161 csa0303@cse.iitd.ernet.in Huzur Saran Department of Computer Science Indian Institute of Technology (IIT), New Delhi, India. (91) (11) 2659-1291 saran@cse.iitd.ernet.in ABSTRACT We consider the problem of peer-to-peer video streaming for a critical private webcast, for a medium sized heterogeneous network. The nodes can form an overlay network based on multicast tree at application level. The nodes are assumed to have different bandwidths and reliabilities, with a majority of the nodes having low bandwidths and low reliability such that they can only receive the video stream. A simulation model has been implemented to compare the single streaming scheme and error resilience schemes with Dual Disjoint Multicast Trees: Stream Replication and Multiple Description Coding (MDC). Simulation results indicate that MDC error resilience scheme provides lower average outage, better video quality and network utilization as the packet loss and node failure probability increases. The error resilience schemes require multiple path diversified, disjoint trees. We discuss the significance of considering heterogeneous bandwidth and node reliability factor for maintaining multiple disjoint trees for error resilience. We propose a disjoint tree algorithm Multi Level Dual Disjoint Trees (MLDDT) that further improves the results of MDC error resilience scheme. Categories and Subject Descriptors C.2 [Computer-Communication Networks]: Distributed Systems; C.4 [Performance of Systems]: Performance attributes. General Terms Algorithms, Measurement, Performance, Reliability, Experimentation, Verification. Keywords Video Streaming, Error Resilience, Multiple Description Coding (MDC), Path Diversity. 1. INTRODUCTION The problem of video distribution over Internet is of considerable importance. Many people have looked into the problem of video content distribution for live events. A central server could be used for distributing video stream to group of people interested. The problem with this approach is that the video server will be heavily loaded and hence the scheme is not scalable. Alternately, the video stream can be distributed in a peer-to-peer manner with each peer receiving the video stream as well as forwarding it further. Ideally IP Multicast could have addressed this problem. However large-scale deployment of IP multicast has not turned feasible among ISPs across the globe [1]. Most research in peer-to-peer video streaming has been focused into peer-to-peer distribution using an overlay network, with an application level multicast protocol. Various application level protocols have evolved like ALMI (Application Level Multicast Infrastructure) [2], CoopNet [3], SplitStream [4] and Narada [5]. ALMI uses a centralized approach, forming a single minimum spanning multicast tree at application level. It has been used in implementing PGP Key server [6]. The issue of interest here is achieving a good load distribution and fault tolerance so as to maintain a consistent and continuous video quality in presence of network errors. Recent work includes work from Microsoft Research (CoopNet and SplitStream), which use the idea of maintaining multiple distribution trees to provide redundant paths and data. They use MDC [8] [9] (Multiple Description Coding) to provide error resilience. Internet TV like P2P TV [11] uses MDC and provides channels for public viewing across the globe. But these types of applications cannot be used to webcast a private group event for a medium-sized group of people (numbering in hundreds or even thousands). The event could be a private community event or a corporate lecture session with the viewers spread across the globe, where there is also a need to retain privacy. Additionally, the private group event can be a critical event, where it is important to retain the continuity of video for the entire session. However, the network is prone to error conditions such as node and link reliability issues and bursty packet losses. A less reliable node or link can fail due to power or ISP connection failure. In a peer-to-peer video streaming distribution using a single multicast tree organization, if a node or link goes down, its descendents in the tree will stop receiving the video stream. They Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. QShine’06, August 7–9, 2006, Waterloo, Ontario, Canada. Copyright 2006 ACM 1-…$5.00.