A first query that is substantially similar to a second query is detected. A network of sensors includes a first sensor, a second sensor, and a data-source sensor, the first and second queries are addressed to the data-source sensor, and the first query is forwarded by the first sensor to the data-source sensor and the second query is forwarded by the second sensor to the data-source sensor. The data-source sensor provides, to the first sensor, results answering the first query. The first sensor provides the results to the second sensor.