  Instant social video sharing which combines the online social network and
user-generated short video streaming services, has become popular in today's
Internet. Cloud-based hosting of such instant social video contents has become
a norm to serve the increasing users with user-generated contents. A
fundamental problem of cloud-based social video sharing service is that users
are located globally, who cannot be served with good service quality with a
single cloud provider. In this paper, we investigate the feasibility of
dispersing instant social video contents to multiple cloud providers. The
challenge is that inter-cloud social \emph{propagation} is indispensable with
such multi-cloud social video hosting, yet such inter-cloud traffic incurs
substantial operational cost. We analyze and formulate the multi-cloud hosting
of an instant social video system as an optimization problem. We conduct
large-scale measurement studies to show the characteristics of instant social
video deployment, and demonstrate the trade-off between satisfying users with
their ideal cloud providers, and reducing the inter-cloud data propagation. Our
measurement insights of the social propagation allow us to propose a heuristic
algorithm with acceptable complexity to solve the optimization problem, by
partitioning a propagation-weighted social graph in two phases: a
preference-aware initial cloud provider selection and a propagation-aware
re-hosting. Our simulation experiments driven by real-world social network
traces show the superiority of our design.
