A tag adapted to be applied to an object is disclosed. The tag includes a wireless communication interface, a processor and a memory. A univocal code, a cipher key and a count value are store in the memory. The tag generates a dynamic code as a function of the cipher key and the count value. Next, the tag varies the count value according to a determined operation, and stores the varied count value in the memory. The tag transmits the univocal code and the dynamic code to a reader device. The tag may transmit the univocal code and the dynamic code in a URL.