Optimal Content Transmission Policy in Publish-Subscribe Mobile Social Networks

We consider the problem of dynamic content distribution in publish-subscribe mobile social networks. Mobile users subscribe to the content provider. Then, when new content is created, the provider transmits it to subscribers (i.e., mobile users) through the base station. The mobile users who have the social relationship (i.e., mobile users in the same community) can transfer the fresh content when they move and meet each other. From the content provider´s perspective, the content transmission policy by the base station can be optimized so that the number of mobile users having the fresh data is maximized subject to the constraint on the maximum waiting time of the new content. An optimization formulation is presented for the content provider to obtain this optimal content transmission policy. Performance evaluation results show that with the optimal content transmission policy, the average number of mobile users having fresh content is larger than that if the new content is transmitted immediately.