KR20030096334A - A method for providing data services for a large number of small-sized data files - Google Patents

Abstract

An apparatus for repeatedly searching for a plurality of data file broadcasts during at least a first time interval and a second time interval comprises: means for receiving at least one file request 303 from a user selecting at least one of the broadcast data files ; Means for initiating a file retrieval process (306, 308) authorized to retrieve at least a first portion of at least one selected data file broadcast during a first time interval; Means for displaying (310) at least a portion of the first portion of the at least one data file among at least a portion of the second time interval; Means for retrieving a second portion of at least one data file broadcast during a second time interval; And means for playing back at least a portion of the second portion of the at least one data file.

Description

A METHOD FOR PROVIDING DATA SERVICES FOR A LARGE NUMBER OF SMALL-SIZED DATA FILES}

In the current information age, people require quick access to all entertainment, news, goods and services. Currently, there is no service that can quickly provide a large number of small data files, such as karaoke audio / video files, to a large number of individual consumers. Internet web pages provide rich text on a variety of topics, but they require two-way communication and require a long time to access existing modem technology. Also, a typical internet web site can send a typical file to a limited number of recipients.

Prior Art FIG. 1 shows a simplified functional block diagram of a data on demand (DOD) system 10. A user makes a selection of audio / video services (such as karaoke music files) listed on an electronic program guide (EPG) on a display screen, such as a television 12, and a set top box (STB) coupled to the television 12 ( 14) to order audio / video selections. The STB 14 may communicate to the DOD server 18 via a bidirectional network via a broadband network 16 such as the Internet. Once the DOD server 18 receives a request from a user (viewer), the DOD server 18 accesses a bank of disk arrays 20 that stores a selection of audio / videos available as EPGs and selects the selected audio. Retrieves the video / video file and sends the selected file to the user over the broadband network. This conventional bidirectional distributed infrastructure 16 consists of a combination of telephone networks and / or cable TV systems. In transmitting the selected file, the video data is encoded based on the appropriate protocol required to achieve the maximum efficiency of the overall system.

Prior Art FIG. 2 is a simplified functional block diagram of the prior art STB 14. The STB 14 includes a demodulator 29, a transport stream demux 22, a video decoder 24, an audio decoder 26, and a clock control unit 28. Once the user's request is processed by the DOD server, the data is sent to the user STB 14. The general prior art STB 14 sends an incoming transport stream to demodulator 20 to demodulate the incoming signal. The demodulated signal is then separated into its separate components by transport stream demux 22. The video data component of the incoming stream is decoded by the video decoder 24 and the audio data component is decoded by the audio decoder 26. The incoming transport stream also provides timing information used by the clock control unit 28. The clock control unit 28 provides the corresponding audio data with a timing output used to correspond to or synchronize the video data.

Prior Art FIG. 3 is a block diagram of a prior art method 40 for DOD transmission of small data files over a network. In order for the user to select a particular audio / visual option, an EPG is provided to the user that includes the available choices and timing. In step 30, the STB 14 tunes to the appropriate channel and receives the transmitted EPG. Next, in step 32, STB 14 provides the user with which to view the EPG. In step 34, user input is sent to the DOD server 18 in the form of a request for a particular audio / visual selection. The STB 14 then predicts the receipt of the requested data file and tunes to the appropriate channel or allocated bandwidth. In step 38, a client request data file is received by the STB 14 and provided to the client in the form of a displayable image after demodulating, demultiplexing and decoding incoming signals. Typically, prior art systems have download speeds of 2 Mb / s to 6 Mb / s. For DOD files, the download speed must be fast enough to allow real time playback of the video.

Typically, karaoke music files are encoded in MPEG format (MPEG-1 or MPEG-2) or in VBR such as DVD format, where the bit rate varies from CBR (constant bit rate) 1.5 Mbs to 4 Mbs. The music playback time varies from 1 to several minutes. Assuming an encoding bit rate of 1.5 Mb / s (MPEG-1), the file length for a 3-minute karaoke song is about 34 Mbytes, much smaller than most movies or other audio / visual files.

There are a number of limitations in current DOD broadcast systems used to transport multiple small data files. The transmission bandwidth required by conventional DOD server systems depends on the number of DOD users since many users demand more bandwidth in proportion. Conventional DOD server systems require bidirectional communication. Conventional DOD systems cannot reproduce files at bit rates faster than the transfer bit rate of the file downloaded for streaming video.

Existing systems require broadband bandwidth and are limited by the number of clients they can service at one time, primarily due to bandwidth requirements. In addition, prior art transmission methods lack the ability to exploit the features and processing capabilities of new STBs with the knowledge of downloading files using more flexible and efficient algorithms.

Therefore, what is needed is a DOD broadcast system that can transmit multiple small data files to multiple clients simultaneously without the need for bidirectional communication with a narrow bandwidth. What is more needed is a more bandwidth-efficient way to download data files by processing the transmitted data using intelligent STB features such as more complex protocols.

Summary of the Invention

The present invention provides a DOD broadcast system capable of transmitting a plurality of small data files to a plurality of clients simultaneously without the need for bidirectional communication with a narrow bandwidth. The present invention provides an STB capable of downloading a data file at a bit rate greater than the data file playback bit rate, which allows data files to be downloaded faster than the files are played. Further provided is a more bandwidth efficient way of processing data transmitted using intelligent STB features such as more complex protocols to download data files.

Briefly, one aspect of the present invention provides for retrieving a plurality of data file broadcasts repeatedly during at least a first time interval and a second time interval: at least one file request from a user selecting at least one of the broadcast data files. Means for receiving; Means for initiating an authorized file retrieval process for retrieving at least a first portion of at least one selected data file broadcast during a first time interval; Means for displaying at least a portion of the first portion of the at least one data file among at least a portion of the second time interval; Means for retrieving a second portion of at least one data file broadcast during a second time interval; And means for playing back at least a portion of the second portion of the at least one data file.

Another embodiment of the present invention teaches a method of transmitting a plurality of small files to a plurality of consumers, the method comprising the steps of: transmitting a plurality of data files to a plurality of users, wherein the authority to receive the data file is provided. Authorized consumers receive, and consumers who are not authorized to receive the selected file are prevented from receiving the file. The method includes transmitting an electronic program guide (EPG) to a plurality of users, where the user selects the selected data file using the electronic program guide. Each data file is sent repeatedly. In addition, each data file has an allocated bandwidth, and the data files are repeatedly transmitted in the corresponding bandwidth.

In one embodiment of the method, an icon corresponding to each data file is displayed via the EPG so that the user selects the data file by selecting the displayed icon. In another embodiment, at least one of the plurality of data files is a karaoke music file that includes audio and visual data.

Alternatively, at least one of the plurality of data files is a text file comprising a graphic and a plurality of pages, wherein at least one page includes text information. The service corresponding to the transaction feature included in the text file is activated by the first user.

The present invention relates generally to on-demand data broadcasting systems. In particular, the present invention relates to a digital DOD broadcast system for transmitting multiple small data files to multiple end users.

1 is a simplified functional block diagram of a DOD system;

2 is a simplified functional block diagram of a conventional STB;

3 is a block diagram of a DOD transmission method over a network;

4 is a simplified block diagram of a DOD broadcast server according to an embodiment of the present invention;

5 is an operational block diagram of a DOD server system according to an embodiment of the present invention;

6 is a block diagram of an intelligent set-top-box in accordance with one embodiment of the present invention;

7 is a flowchart illustrating a method for downloading data files according to one embodiment of the present invention;

7A shows another two-way authentication process for purchasing selected DOD services according to one embodiment of the present invention;

8 is a simplified diagram illustrating data block transmission according to an embodiment of the present invention;

9 is a simplified diagram illustrating data block transmission according to another embodiment of the present invention;

10 is a flow chart illustrating a text / graphic file download operation according to an embodiment of the present invention; And

11 is a flow chart illustrating text / graphic file handling in accordance with one embodiment of the present invention.

The present invention provides a DOD broadcast system capable of transmitting multiple small data files to multiple clients simultaneously without the need for bidirectional communication in narrowband. The present invention provides an STB capable of downloading a data file at a bit rate greater than the data file reproduction bit rate, and allows data files to be downloaded faster than the files can be reproduced. This is accomplished by repeatedly sending each small data file to all existing consumers over its own allocated bandwidth. The consumer uses an intelligent STB to access any selected data file with only a short delay. The intelligent STB also restricts consumers access to services to which they were not subscribed. In this way, individual files do not have to be sent to individual consumers to restrict access.

4 is a simplified block diagram of a transmission server according to an embodiment of the present invention. The DOD server 200 includes a plurality of channel servers 211, a plurality of up converters 212 corresponding to the channel servers 211, a combiner / amplifier 214, a central control server 202, and a central storage device. 204 and coupled as shown via data bus 206. As described below, the central control server 202 not only controls the off-line operation of the channel server 211 but also initiates real time transmission when the channel server 211 is ready. The central storage 204 typically stores data files in digital form. However, any suitable mass storage storage device may be used.

In an exemplary embodiment, the data files stored in the central storage device 204 are over a standard network interface (eg, an Ethernet connection) by an authorized computer connected to the network, such as the central control server 202. Accessible. Channel server 211 provides the data file retrieved from central storage 204 according to instructions from central control server 202. The retrieval of digital data and the scheduling of transmission of digital data for the DOD are performed "off-line" to prepare each channel server 211 for real-time data transmission. Each channel server 211 notifies the central control server 202 when it is ready to provide the DOD, at which time the central control server 202 can control the channel server 211 to initiate DOD transmission.

In a preferred embodiment, the central control server 202 includes a graphical user interface (not shown) through which service providers can transfer data by drag-and-drop operations. The central control server 202 also authenticates and controls the channel server 210 to start or stop according to the delivery matrix. Systems and methods for providing a one-way DOD broadcast matrix, filed May 31, 2000, Koh Hoang, entitled “SYSTEM AND METHODS FOR PROVIDING VIDEO ON DEMAND SERVICES FOR BROADCASTING SYSTEMS”, having application number 09 / 584,832. Is taught in a patent application, which is incorporated herein by reference.

Each channel server 211 is assigned to a channel and coupled to receive up-converter 212. The channel server 211 transmits DOD information to each up-converter 212. The output of each channel server 211 is a quadrature amplitude modulated (QAM) modulated intermediate frequency (IF) signal with an appropriate frequency for the corresponding up-converter 212. The QAM-modulated IF signals depend on the adopted standard. The standard currently adopted in the United States is the data-over-systems-interface-specification (DOCSIS) standard, which requires approximately 43.75 MHz IF frequencies.

Up-converters 212 convert IF signals received from channel servers 211 into radio frequency signals (RF signals). RF signals, including frequency and bandwidth, depend on the desired channel and the adopted standard. For example, under current standards in the United States for cable television channel 80, the RF signal has a frequency of approximately 559.25 MHz and a bandwidth of approximately 6 MHz.

The outputs of the up-converters 212 are applied to the combiner / amplifier 214. The combiner / amplifier 214 amplifies, adjusts and combines the received RF signals and then outputs the signals to the data network 52 (FIG. 5). According to one embodiment, the data network is a cable television distributed network, or other one-way data distributed network.

In an exemplary embodiment, 20 broadcast channels are allocated for the transmission of karaoke files and other small data files. Karaoke music files are typically encoded in MPEG format (MPEG-1 or MPEG-2) or in VBR such as DVD format, where the bitrate varies from CBR (constant bit rate) 1.5 Mbs to 4 Mbs. The music playback time varies from 1 to several minutes. Assuming an encoding bit rate of 1.5 Mb / s (MPEG-1), the file length of a 3-minute karaoke song is about 34 Mbytes.

For example, assume that each channel has 36 Mbs of available bandwidth (for an 8 MHz kale system using QAM64). Each small data file is allocated to a 1 Mbs transmission band. This allows 36 karaoke files to be sent on each channel and a total of 720 karaoke data files to be sent on 20 channels. If the subscriber is authorized to access the normal karaoke file (3-minute playback time encoded using MPEG-1), the download time is approximately 4.5 minutes ((3 minutes X 1.5 Mbs) / 1 Mbs). The table below shows an example of the relationship between bit rate, allocated bandwidth, number of small data files downloaded and download time for a typical three minute karaoke song.

TABLE 1

Encoded Bit Rate (Mbs) Allocated Bandwidth (MHz) Number of karaoke titles Max download time (minutes) 1.5 One 36 4.5 1.5 2 18 2.25 2 One 36 6.0 2 2 18 3.0

5 illustrates a DOD broadcast system 50 according to an embodiment of the present invention. The DOD broadcast server 200 transmits an RF signal including a plurality of small data files (such as karaoke files) to the plurality of receiving STBs 100 through the broadcast transmission medium 52. According to one embodiment, transmission medium 52 is a cable television transmission medium, such as a medium used by existing cable television providers. Unlike conventional DOD broadcast systems, all receiving STBs 100 receive all transmitted data files. The user STB must have appropriate authorization to view or store the selected data files.

6 shows a simplified operational block diagram of an intelligent STB 100 in accordance with an embodiment of the invention. The STB 100 couples these devices as shown, QAM demodulator 102, CPU 104, local memory 108, buffer memory 110, decoder 112 with video and audio decoding capabilities, and as shown. And a fast data bus 122. CPU 104 selects data in response to a client request, decodes the selected data, decompresses the decoded data, reassembles the decoded data, and stores the decoded data in local memory 108 or buffer. It stores in the memory 110, and controls the overall operation of the intelligent STB 100 to transfer the stored data to the decoder (112). In an exemplary embodiment, local memory 108 includes both non-volatile memory (eg, hard drive) and secure memory (eg, ROM chip), and buffer memory 110 includes volatile memory. do.

In one embodiment, the QAM demodulator 102 includes a transmitter and receiver module and one or more of the following: a personal encryption / decryption module, a forward error correction decoder / encoder, tuner control, downstream and upstream processors, a CPU And memory interface circuitry. The QAM demodulator 102 receives the modulated IF signals, stores the data by sampling and modulating the signals.

In an example embodiment, when access is granted, decoder 112 decodes the data blocks of the selected data files into images displayable on output device 124. The decoder 112 supports commands from subscribing clients, such as play, stop, stop, step, rewind, fast forward, and the like. The decoder 112 provides the decoded data to the graphic overlay module 114. The graphic overlay module 114 improves the displayed graphic quality, for example by providing alpha blending or picture in picture (PIP) capabilities. The graphic overlay module then provides an output device 124 for displaying the improved display signal to the user. In an exemplary embodiment, the graphics overlay module 114 may be used for graphics acceleration during game play mode, for example when the service provider provides an on-demand game using the system according to the invention. The output device 124 is a suitable device such as a television, a computer, any suitable display monitor, a VCR, or the like.

The user interface 118 enables user control of the STB 100 and is any suitable device such as a remote control device, a keyboard, or the like. Communication link 120 provides additional communication connections. It is coupled to another computer or used to implement bidirectional communication. The data bus 122 is a commercially available "fast" data bus suitable for performing data communication in a real time manner as required by the present invention. Suitable embodiments are USB, firmware, and the like. Although the services are broadcast to all cable subscribers, only DOD subscribers with STB 100 authorized to view the selected DOD service can decode and enjoy the selected service.

According to an embodiment, the intelligent STB 100 may play the file before the selected data file is completely downloaded. This process is discussed in more detail with reference to FIG. 8 below.

7 shows a process 300 for ordering one or more small data files (such as karaoke files) in accordance with an embodiment of the present invention. The process 300 begins at step 302 where the STB 100 (FIG. 5) receives an EPG program from the DOD broadcast server 200 (FIG. 5). The EPG program lists all the files available from the DOD server. In step 303, the user selects one or more titles from the EPG by pressing a button associated with each desired file. In step 306, the STB determines if the user is authorized to view the selected data file. This involves examining the values stored in STB 100 (FIG. 5) and comparing these values to the level of subscription required for each selected data file. Such authentication methods are taught in Koi Hoang's patent application “CONTROLLING DATA-ON-DEMAND CLIENT ACCESS” filed on July 9, 2001 and having application number 09 / 902,503. Other methods of authenticating access to the selected data file include bidirectional communication with the DOD server 200 (FIG. 5) or other remote locations.

If the user is authorized to view the selected data file (step 308), the process proceeds to step 309. In step 309 the STB begins storing the selected files. In step 310 the STB plays the title selected for viewing by the user.

If the user is not authorized to view the selected data file (step 308), the STB displays a message denying access at step 312. The STB also displays a message with an indication of how the user can gain access to the rejected service.

7A shows another two-way authentication process 350 for purchasing selected DOD services. The process 350 begins at step 352 where the STB 100 (FIG. 5) receives an EPG program from the DOD broadcast server 200 (FIG. 5). The EPG program lists all the files available from the DOD server. In step 353, the user selects a title from the EPG by pressing a purchase button associated with the desired title. In step 354, the STB forwards a request to the server 200 (FIG. 5) for permission to view the desired selection. This request is sent to the server 200 via a telephone modem or uplink.

In step 356, server 200 updates the payment system by forwarding to the STB requesting authentication for the selected title and debiting the user's account. Authority is communicated via transmission medium 52 (FIG. 5) via either modem or downstream. In step 358, the STB initiates receiving the rights and storing the requested title. In step 360 the STB plays the title selected for the user to watch.

8 is a diagram of an exemplary broadcast of two separate small data files, such as karaoke files at 400. In this example, two titles are repeatedly broadcast on two separate bandwidths in the same channel. The first title 402 (title 1) takes two minutes of playback time and one minute to download. The second title 404 (title 2) takes four minutes of playback time and two minutes to download. Each title is repeatedly broadcast simultaneously in its own allocated bandwidth.

Once the desired title (e.g., Title 1 and Title 2) is selected, step 303 (FIG. 7), STB 100 starts downloading Title 1 and Title 2, and starts playing Title 1 one minute later. . When STB 100 starts to play Title 1, the STB 100 continues to download Title 2, which takes another minute. Once Title 1 completes playback, STB 100 starts playback of Title 2.

The STB 100 can always download each selection with a minimum amount of time by assembling data blocks from the end of one transfer of the title and from the start of subsequent repeated transfers of the same title. This process is taught in Koi Hoang's patent application “METHOD AND APPARATUS FOR TRANSMITTING NON-VOD SERVICES”, filed October 25, 2000, with agent control number 60595-301801, which is incorporated herein by reference. The STB can download multiple files simultaneously because each file is allocated to a separate transmission bandwidth.

In a preferred embodiment, STB 100 can download files at a bit rate that is greater than the bit rate that files can reproduce. In this embodiment, the transmitted data files consist of a sequence of data blocks containing data related to the selected file. The STB may start playing the selected title as soon as the first data block of the sequence corresponding to the selected title is received. The STB must be able to download data blocks of the selected title faster than the title is played for the user to ensure smooth playback of the title. In one embodiment, the STB calculates the scheduled download time to determine when the data file can be played. This calculation depends on the encoded bit rate and the transmission bit rate, and the buffer block size. Since the download starts with a data block other than the first data block of the file, the waiting time is greater than the standard download time. The time at which the STB starts playing the selected file can be calculated as follows:

Ts≥Tp * (Td / Tp- (NB-1) / NB (Equation 1)

Ts: the time to start playback for the data file

Tp: time required to play the data file

EBR: Encoded Bit Rate

TBR: Transmission Bit Rate

Td: time required to download the complete file (Td = file size / transfer bit rate)

NB: Number of data blocks in the file (NB = data file size / buffer block size)

For example, assuming a buffer block size of 1.5 MB, 3 minutes, a 45 MB file (NB = 30) encoded at 2 Mb / s, and a transmission rate of 1 Mb / s, a waiting time Ts of approximately 186 seconds is required. Ts = 3 * (2 / 1- (30-1) / 30) = 186 seconds. In the second embodiment, assuming a buffer block size of 1.5 MB, 1 minute, a 6 MB file encoded at 2 Mb / s (MB = 4), and a transfer rate of 1 MB / s, a wait time Ts of approximately 75 seconds is taken. . Ts = 1 minute * (2 / 1- (4-1) / 4) = 75 seconds.

9 illustrates another method of transmitting multiple small data files on a shared bandwidth of a single transport channel. 9 illustrates a sequence of data blocks transmitted in a first transmission bandwidth 502 and a second transmission bandwidth 504 of an exemplary transport channel. The first bandwidth 502 may first determine the data blocks 506 of the first sequence corresponding to the first karaoke song, followed by the data blocks 508 of the second sequence corresponding to the second karaoke song, and finally Data blocks 510 of the third song are transmitted. The bandwidth 502 repeats the transmission of three karaoke songs in this sequence infinitely. The second transmission bandwidth 504 transmits a fourth karaoke song 512, a fifth karaoke song 514, a sixth 516 and a seventh karaoke song 518. The bandwidth 504 also repeats this sequence indefinitely. According to this aspect of the invention, more small data files are available for the same number of allocated channels, but larger latency is required.

10 shows a process 600 for receiving a digital on-demand text (TOD) service in accordance with one embodiment of the present invention. The process 600 begins at step 602 where the STB 100 (FIG. 5) receives an EPG program from the DOD broadcast server 200 (FIG. 5). The EPG program lists all files (books, magazines, periodicals, etc.) available from the DOD server. File types include movies, digital text files, music, and the like. In step 604, the user selects the desired digital text file from the EPG by pressing a remote control button associated with the desired service, which remote control has an integrated mouse or roller ball. In step 606, the STB determines if the user is authorized to view the digital text file. This involves examining the values stored in STB 100 (FIG. 5) and comparing these values to the subscription level required for each selected digital text file. Such authentication methods are taught in Koi Hoang's patent application “CONTROLLING DATA-ON-DEMAND CLIENT ACCESS” filed on July 9, 2001 and having application number 09 / 902,503. Other methods of authenticating access to the selected digital text file include bidirectional communication with the DOD server 200 (FIG. 5) or other remote locations.

If the user is authorized to view the selected file (step 606), the process proceeds to step 610. In step 610, the STB begins storing the selected file. In step 610, the STB begins storing the requested text. In step 612, the STB displays the text to the user.

In one embodiment, 4000 programs (services / channels) with as many as 250 pages / channels (100k total pages) may be transmitted on a single physical channel. However, multiple programs transmitted on a single physical channel cause longer response times for accessing the desired service. Each program includes a number of pages. The more pages a program has, the more time it takes to access the program. The programs include a page index that describes the content of each text page.

Text / graphical displays are also possible, but this requires a corresponding increase in the number of data and response times. Available formats include JPEGs, bitmaps, and the like. The page can include text and graphical images. The page may also include a hypertext language (HTML, etc.).

Text files may include publications such as newspapers, magazines, books, and government publications. Other information available in the text may include weather, transportation schedules, hotel information, stock information, shopping, breaking news, and third party payment services.

11 shows a process 700 for performing a transaction on a display page in accordance with the present invention. In step 702, the STB receives a text page that includes one or more interactive transaction features. In step 704 the STB displays the page to the user. The transaction features are identified starting from the displayed page. The features are bold or other colors. Possible transaction features may include icons for paying from a third vendor, purchasing selected goods or services, voting on political elections, and the like. The home shopping channel page may include, for example, icons for purchasing the selected item. The stock channel page may have purchase order icons that indicate various stocks, quantities or prices.

In step 706 the user activates the selected transaction feature. In step 708, the STB delivers a message corresponding to the content of the selected feature to a location corresponding to an entity corresponding to the selected feature. For example, if a user double-clicks a purchase of IBM's 100 shares for $ 100, the STB sends a message requesting a purchase to the stock broker website associated with the icon via a telephone modem, local area network, or other network. To pass. If, for example, the user selects a gas cost payment icon, the STB forwards a message authorizing the transfer to the appropriate utility.

In step 710, the receiving site performs any function corresponding to the specific message delivered.

The foregoing examples illustrate certain exemplary embodiments of the invention, from which other embodiments, variations, and modifications will be apparent to those skilled in the art. Accordingly, the invention is not limited to the specific embodiments discussed above, but will be defined by the following claims.

Claims (41)

Transmitting a plurality of data files to a plurality of users immediately, wherein at least one of the data files is transmitted at a rate greater than a play rate of the data file. To send to a plurality of users. 2. The method of claim 1, comprising transmitting an electronic program guide (EPG) to the plurality of users, wherein the user can select the selected data file using the electronic program guide. The method of claim 1, wherein each data file is transmitted repeatedly. 4. The method of claim 3, wherein each data file has an allocated bandwidth such that the data file is repeatedly transmitted at the corresponding allocated bandwidth. 3. The method of claim 2, wherein an icon corresponding to each data file is displayed via an EPG so that the user can select the data file by selecting the displayed icon. 2. The method of claim 1, wherein at least one of the plurality of data files is a karaoke music file comprising audio and visual data. The method of claim 1, wherein at least one of the plurality of data files is a text file comprising text information. 8. The method of claim 7, wherein the text file includes a plurality of pages, and at least one page includes text information. 10. The method of claim 8, wherein at least one of the pages comprises a graphical image. 10. The method of claim 9, wherein the graphic image is formatted as a JPEG image. The method of claim 8, wherein at least one of the plurality of pages is an index including information representing the content of at least one other page. 8. The method of claim 7, wherein a service corresponding to a transactional feature included in the text file can be performed by the first user. 13. The method of claim 12, wherein a set top box (STB) delivers the electronic message in response to the activation of the transactional feature. The method of claim 13 wherein the electronic message includes an order for purchase of a product from a third provider. The method of claim 13, wherein the electronic message includes an order for purchase of a service from a third provider. The method of claim 13, wherein the electronic message includes an order instructing the funds to be deposited in an account for payment. Receiving a user input indicating at least one selected data file; Initiating an approved download of the first part of the selected data file broadcast during the first time interval; Displaying at least a portion of said first part of a selected data file; At least a portion of the first part is displayed during a second time interval to retrieve a second part of the data file broadcast during the second time interval; And Displaying at least a portion of the second part of the selected data file; And periodically downloading the data file broadcast using the intelligent STB. The method of claim 17, Retrieving additional parts of the data file broadcast for additional time intervals; And Rearranging all parts to reconstruct the complete data file; How to include more. The method of claim 17, Determining the required waiting time before playing the data file to confirm that data blocks corresponding to the data file are retrieved before they are scheduled to be played. Means for receiving a file request from a user who has selected at least one of the broadcast data files; Means for initiating approved file retrieval processing to retrieve at least a first part of a data file broadcast during a first time interval; Means for displaying at least a portion of the first part of a data file at at least a portion of a second time interval; Means for retrieving a second portion of a data file broadcast during a second time interval; And Means for displaying at least a portion of the second portion of a data file; And repeating the retrieval of the data file broadcast over at least the first and second time intervals. 21. The apparatus of claim 20, further comprising means for requesting approval for retrieval of the requested file. 21. The apparatus of claim 20, further comprising means for retrieving a third part of a data file broadcast during a third time interval, and means for rearranging the first, second, and third parts to reconstruct a complete data file. Containing device. 21. The apparatus of claim 20, wherein the EPG is received by the user STB and provided to the user. 21. The method of claim 20, wherein the user STB automatically determines the download time and playback time from the data sent with the EPG corresponding to the file selected by the user and automatically displays at least a portion of the file after the waiting period, The waiting period duration corresponds to the download time and the playback time. 22. The apparatus of claim 21, wherein the user STB automatically calculates a waiting period duration in correspondence with the playback time and the download time. 23. The apparatus of claim 22, wherein the waiting period further corresponds to the number of data blocks containing the file. An input device for receiving a file request from a user who has selected at least one of the broadcast data files; A processor that initiates an approved file retrieval process to retrieve at least a first part of a data file broadcast during a first time interval; And An output device for displaying at least a portion of said first part of a data file in at least a portion of a second time interval; Wherein the processor is further operable to search for a second portion of the data file broadcast during the second time interval, wherein the processor repeatedly retrieves the data file broadcast for at least the first and second time intervals. 28. The apparatus of claim 27, further comprising a communication port for requesting approval for retrieval of the requested file. 28. The system of claim 27, wherein the processor is further operated to retrieve a third part of the data file broadcast for a third time interval and to rearrange the first, second, and third parts to reconstruct the complete data file. Device characterized in that. 28. The apparatus of claim 27, wherein the EPG is received by the user STB and provided to the user. 28. The apparatus of claim 27, wherein the user STB automatically determines the download time and playback time from the data sent with the EPG corresponding to the file selected by the user and automatically displays at least a portion of the file after the waiting period, wherein the waiting The duration of time corresponds to the download time and the playback time. 29. The apparatus of claim 28, wherein the user STB automatically calculates a waiting period duration in correspondence with the playback time and the download time. 30. The apparatus of claim 29, wherein the waiting period further corresponds to the number of data blocks containing the file. A DOD broadcast server for broadcasting a plurality of data files; A transmission medium in communication communication with the DOD broadcast server; And A plurality of receivers in communication with the DOD broadcast servo via the transmission medium; Including; The DOD broadcast server repeatedly transmits a plurality of data files to the plurality of receivers via the transmission medium, The receiver is operative to allow the user to select at least one data file, The receiver is operative to perform an authorization check associated with the selected data file, The receiver is further operated to accept the selected data file, and The receiver is further operative to display a portion of the selected data file to the user, On-demand data (DOD) broadcast system for transmitting many small data files. A user input device for selecting a predetermined data file; A first communication link for requesting permission to access the selected data file; A second communication link for accepting permission to access the selected data file; A processor for tuning within a bandwidth corresponding to the selected data file; And A third communication link for receiving the selected data file; Set-top box device for accessing small DOD data file broadcast over a wide area network including a. 36. The apparatus of claim 35, comprising a display device for displaying at least a portion of the selected data file. 36. The apparatus of claim 35, wherein the processor is further operable to automatically display the selected data file when the minimum portion of the selected data file is accepted. 37. The apparatus of claim 36, wherein the input device is operative to receive a user input activating transaction feature, and visual data associated with the transaction feature is displayed via the display device. A storage server for storing data files; A channel server for retrieving a selected data file from the storage server; And A transmitter that repeatedly transmits a first data file over an allocated bandwidth to allow a receiver to access the first data file within a predetermined time interval; DOD broadcast server device for transmitting a plurality of small DOD data files to a plurality of recipients over a wide area network comprising a. 40. The apparatus of claim 39, wherein the time interval is smaller than the time required to download the first data file. The method of claim 39, A service approval processor operative to accept an authorization request from the client and provide an authorization code for the client to view the selected data file, The service approval processor is operable to transmit information indicating the selected data file to a billing device, and The billing device is operative to update a client expense record in response to the information; Device characterized in that.