Method to determine the completeness of a service guide

摘要

Provided are apparatuses and methods in a digital broadcast transmission system for deducing the contents or topology of an ESG fragment, transport object, container or session. In one example, descriptors may be transmitted on a first channel that may correspond to ESG fragments transmitted on a second channel. The first and second channel can be received at a subscriber terminal. The subscriber terminal may thus be apprised of the topology of the ESG fragments to minimize the amount of information the subscriber terminal needs to receive. This provides an optimized overall retrieval of the ESG fragments.