Energy efficient media streaming inwireless hybrid peer-to-peer systems

With the proliferation of sophisticated wireless devices with more than one network interfaces, it is now possible for the devices to form hybrid wireless networks. Specifically, we consider a hybrid wireless networking scenario in which each device has two heterogeneous wireless network interfaces: a server interface (e.g., a CDMA2000 cellular interface) and a peer interface (e.g., a IEEE 802.1 Ig WLAN interface). Our insight is that we could exploit the heterogeneity in energy consumption in such a dual-interface networking capability. In view of the higher energy consumption in using the server interface compared with using the client interface, we propose two novel protocols where neighboring clients form either a master-slave or peer-to-peer relationship to reduce their energy consumption. For the master-slave relationship, each master retrieves media packets from the server and sends them to its slaves via the peer interface. On the other hand, each peer-to-peer relationship consists of one coordinator and at least one helpers. Both coordinator and helpers are responsible for retrieving media packets from the server. Our analysis shows that the two proposed relationships reduce the energy consumption of participating clients. Furthermore, the relationships are stable where rational clients would not voluntarily leave and unilaterally deviate from the coalition. We evaluate their performance in homogeneous and heterogeneous client distributions. Simulation results indicate that both relationships improve streaming performance without violating the energy consumption constraints of clients.