No abstract

No abstract

With the multi-fold development in communication technology, there has been a rapid growth in consumption of multimedia services using mobile devices. In particular, lots of research has been done to provide multimedia services using a 3G/WLAN dual mode to mobile device users. All users download contents from content providers through cellular networks and can share their contents with their neighbors. However, we believe that selfish users (or users with limited resources) are not willing to cooperate or share their contents with other users.In this paper, we propose an incentive scheme that gives the benefit of contents sharing to users in a 3G/WLAN dual mode supporting network. There are two types of users: premium users and ordinary users. Premium users can get high quality contents at the expense of spending their own money and resources of power and bandwidth, while ordinary users receive plain quality contents freely or with paying little amount of money. Our incentive mechanism designs the content provider to offer each premium user a discounted price for downloading high quality contents. Through our approach, each premium user will receive some incentive of a discounted price for receiving high quality contents in proportion to the contribution to the content provider. By doing so, the content provider can increase its total utility too. Our simulation results confirm that our proposed incentive scheme performs well.

In this paper, we propose a novel P2P VoD streaming system, named PECAN where each peer adjusts its cache capacity adaptively to meet the server's upload bandwidth constraint and achieve the fairness. For doing so, we first propose a new cache replacement algorithm that designs the number of caches for a segment to be proportional to its popularity. Second, we mathematically prove that if the cache capacity of a peer is proportional to its segment request rate, the fairness between upload and download amounts at each peer can be achieved. Third, we propose a method that determines each peer's cache capacity adaptively according to the constraint of the server's upload bandwidth. Through simulations, we show that PECAN meets the server upload bandwidth constraint, and achieves the fairness well at each peer.

No abstract