In peer-to-peer overlay or video broadcast, peers contribute a portion of the bandwidth to the overlay in return or the service. In the presence of network heterogeneity, it is not well understood how much bandwidth peers should contribute and receive in return. Existing protocols implicitly assume peers are either completely altruistic (which leads to airness concerns) or completely selfish (which leads to sub-optimal performance). In this paper, we argue that altruism should be explicitly considered. We propose a policy framework in which a wide range of altruism can be modeled and parameterized. The key findings are (i) the level of altruism has significant implication on the overall performance of the receivers; even a small degree of altruism goes a long way in improving their performance, and (ii) a wide range of altruism policy can be implemented efficiently in a distributed fashion. We validate these claims using simulation, with traces from real Internet broadcast events.
['Yang-hua Chu', 'Hui Zhang']
Considering altruism in peer-to-peer internet streaming broadcast