1. A method for identifying content, performed by a computing device, the method comprising the steps of: a) marking a content element with a global mark by a global watermark generation device; b) marking the content element with a local mark by a local server in a local cluster; c) presenting the marked content element; d) detecting at least part of the presented content element; e) extracting the global mark and the local mark from the detected part of the content element; f) identifying the extracted local mark by a local watermark resolution server and the global mark by a global watermark resolution server; and g) identifying the content element based on the global and local mark.