1. An apparatus comprising: circuitry configured to receive a transport stream of a digital television broadcast signal having trigger information inserted into not all Program Clock Reference (PCR) packets of the transport stream but only PCR packets at adequate timings to enable successful interlocking with an audio visual content on a network server; circuitry configured to extract the trigger information from the adequate timings of the PCR packets to access data content interlocking with the audio visual content on the network server, wherein the trigger information comprises a diffusion parameter which controls access timing to the network server so as to avoid a concentration of access to the network server, and wherein the diffusion parameter indicates a period of time by which access to the network server is to be delayed; and circuitry configured to initiate access to the data content on the network server based on the trigger information.