Generally, an Electronic Service Guide (ESG) enables a terminal to communicate what services are available to end users and how the services may be accessed. ESG fragments are independently existing pieces of the ESG. Traditionally, ESG fragments comprise Extensible Markup Language (XML) documents or fragments of XML documents, but more recently they have encompassed a vast array of items, such as for example, a Session Description Protocol (SDP) description, a textual file, or an image. The ESG fragments describe one or several aspects of a service or broadcast program, available currently or in the future. Such aspects may include for example: free text description, schedule, geographical availability, price, purchase method, genre, and supplementary information such as preview images or clips. Audio, video and other types of data comprising the ESG fragments may be transmitted through a variety of types of networks according to many different protocols. For example, data can be transmitted through a collection of networks usually referred to as the “Internet” using protocols of the Internet protocol suite, such as Internet Protocol (IP) and User Datagram Protocol (UDP). Data is often transmitted through the Internet addressed to a single user. It can, however, be addressed to a group of users, commonly known as multicasting. In the case in which the data is addressed to all users it is called broadcasting.
One way of broadcasting data is to use an IP data casting (IPDC) network. IPDC is a combination of digital broadband broadcast and Internet Protocol. Through such an IP-based broadcasting network, one or more service providers can supply different types of IP services including on-line newspapers, radio, and television. These IP services are organized into one or more media streams in the form of audio, video and/or other types of data. To determine when and where these streams occur, users refer to an ESG. One example used in Digital Video Broadcasting (DVB) streams is an electronic program guide (EPG). One type of DVB is Digital Video Broadcasting-Handheld (DVB-H), a recently developed technology that increases the capabilities and services available on small handheld devices, such as mobile telephones. The DVB-H is designed to deliver data to a battery-powered terminal device.
The present invention, however, is also is applicable to other traditional digital mobile broadcast systems such as, for example, Terrestrial Digital Audio Broadcasting (T-DAB), Terrestrial/Satellite Digital Media Broadcasting (T/S-DMB), Integrated Services Digital Broadcasting—Terrestrial (ISDB-T), and Advanced Television Systems Committee (ATSC), proprietary systems such as Qualcomm MediaFLO/FLO, and non-traditional systems such 3rd Generation Partnership Project Multimedia Broadcast/Multicast Services (3GPP MBMS) and 3rd Generation Partnership Project 2 Broadcast/Multicast Service (3GPP2 BCMCS).
As images and other large files predominate the ESG transport, a need exists to efficiently transport the ESG fragments across the desired networks to the end receivers. Previous systems transmitted a header before the ESG, however, this is quite inefficient because if containers carrying ESGs are transmitted before the header, the information is inaccessible until the header arrives and there is the risk of not receiving the header, thereby rendering the information in the container useless. Current attempts focus on associating several fragments together; however, these attempts have been largely unsuccessful due to the lack of unique identification of the fragments, an efficient header or indexing structure, or requiring the presence of repetitive parameters. There is also a need in the art for ESGs to be visible to the end user as soon as possible.