Date Added: Mar 2011
Recently, sensor databases have been used for many applications such as environment observations or weather forecasting. To construct sensor databases, some researches focus on the rounding sink approach. In the approach, rounding sinks repeatedly round in the area that sensors are deployed and collect data from each sensor. Compared with the traditional wireless sensor network approach, the rounding sink approach can reduce communication traffic since rounding sinks collect sensor data directly from sensors. Some data collection protocols to improve the effectiveness of the data collection by rounding sinks have been proposed, but they do not consider the data amount that each sensor has.