Three stakeholders come into play in peer-to-peer (P2P) video-on-demand (VoD), namely peers/viewers, content providers and ISPs. Different design choices have been proposed to improve quality of user experience, to bring down content server bandwidth cost and to reduce ISP-unfriendly traffic. However, it is unclear whether the ability of these design choices to meet interests of one stakeholder comes at the expense of their ability to satisfy the other stakeholders. Yet, another question remains open for two different types of mesh-based P2P VoD protocols: How well do the regular P2P VoD protocol and the network coding-based P2P VoD protocol perform compared to each other? In this paper, we present a simple performance versus cost framework (PCF) to evaluate impact of different design choices. Via detailed PCF-based simulations, we compare the two P2P VoD protocols and show that the two protocols each has its own territory on which it excels at efficiency. We reveal many important findings about P2P VoD design and hope they are useful to P2P VoD designers.
