  With a sponsored content scheme in a wireless network, a sponsored content
service provider can pay to a network operator on behalf of the mobile
users/subscribers to lower down the network subscription fees at the reasonable
cost in terms of receiving some amount of advertisements. As such, content
providers, network operators and mobile users are all actively motivated to
participate in the sponsored content ecosystem. Meanwhile, in 5G cellular
networks, caching technique is employed to improve content service quality,
which stores potentially popular contents on edge networks nodes to serve
mobile users. In this work, we propose the joint sponsored and edge caching
content service market model. We investigate an interplay between the sponsored
content service provider and the edge caching content service provider under
the non-cooperative game framework. Furthermore, a three-stage Stackelberg game
is formulated to model the interactions among the network operator, content
service provider, and mobile users. Sub-game perfect equilibrium in each stage
is analyzed by backward induction. The existence of Stackelberg equilibrium is
validated by employing the bilevel optimization programming. Based on the game
properties, we propose a sub-gradient based iterative algorithm, which ensures
to converge to the Stackelberg equilibrium.
