  Crowdsourced mobile video streaming enables nearby mobile video users to
aggregate network resources to improve their video streaming performances.
However, users are often selfish and may not be willing to cooperate without
proper incentives. Designing an incentive mechanism for such a scenario is
challenging due to the users' asynchronous downloading behaviors and their
private valuations for multi-bitrate coded videos. In this work, we propose
both single-object and multi-object multi-dimensional auction mechanisms,
through which users sell the opportunities for downloading single and multiple
video segments with multiple bitrates, respectively. Both auction mechanisms
can achieves truthfulness (i.e, truthful private information revelation) and
efficiency (i.e., social welfare maximization). Simulations with real traces
show that crowdsourced mobile streaming facilitated by the auction mechanisms
outperforms noncooperative stream ing by 48.6% (on average) in terms of social
welfare. To evaluate the real-world performance, we also construct a demo
system for crowdsourced mobile streaming and implement our proposed auction
mechanism. Experiments over the demo system further show that those users who
provide resources to others and those users who receive helps can increase
their welfares by 15.5% and 35.4% (on average) via cooperation, respectively.
