Active watermarks and watermark agents

An apparatus in a node in a network for monitoring performance of an action involving one or more watermarked digital representations in other nodes in the network, the node including a processor and a memory device to which the processor has access and the apparatus comprising:

• an agent generator in the memory device that, when executed by a processor, generates a watermark agent, the watermark agent including a program that, when executed, reads the watermarked digital representation's watermark in one or more other nodes in which the watermark agent is resident and determines whether the action has been performed and thereupon sends a message concerning the performance to the apparatus for monitoring performance, the watermark agent proceeding to the one or more other nodes, becoming resident therein, and the program being executed therein;
• and
• a message handler in the memory device that, when executed by the processor, receives the message sent by the watermark agent from the one or more other nodes in which the watermark agent is resident and deals therewith.

A method practiced in a node of a network of monitoring performance of an action involving a set of watermarked digital representations resident in the node, the node including a processor and a memory device accessible to the processor and the method comprising the steps performed by the processor of:

• receiving a watermark agent in the node and storing the watermark agent in the memory device, the watermark agent including a program which, when executed in the node, reads the watermarks in the watermarked digital representations of the set, makes a determination whether the action has been performed and/or is potentially performable for each of the watermarked digital representations, and responds to the determination;
• and
• executing the program in the node.