Overall, the energy savings are not as large as we initially expected. The reason turned out to be an artifact of YouTube control traffic which mixes with the content bursts. Figure 6 illustrates what happens during YouTube streaming via the proxy for Nexus One as an example. The client establishes several TCP connections to YouTube servers. The proxy shapes only the traffic of the connection that carries the video content. Those packets are visible as tall bursts (black) in the traffic trace on top and the packets of other connections are visible as shorter spikes (red). The