MXPA00002644A - Access system and method for providing interactive access to an information source through a networked distribution system - Google Patents

Abstract

An access system (10) and method provide interactive access to an information source, such as the Internet, through a networked distribution system, such as a television distribution system (11). Each user in the television distribution system can access the Internet through an associated terminal (54) by sending commands through an upstream channel (22) to a headend server (38) which is interfaced between a television network headend (34) and an Internet Service Provider (ISP) (60). The headend server manages all Internet information requests from the terminals by forwarding the requests to the ISP and receiving the requested information therefrom. An Internet Protocol (IP) address is assigned only to the headend server which keeps track of the terminals requesting information by means of terminal identification numbers or codes associated with each request. The headend server also maintains a plurality of Internet browser applications (75) active at all times to insure that a terminal requesting Internet access can be immediately interfaced to the ISP through one of the active browser applications. Each of the downstream television signals includes a vertical synchronization signal that is preferably employed to generate a framing signal for synchronizing upstream transmission of the data packets comprising the information requests from the terminals.

Description

SYSTEM AND METHOD OF ACCESS TO PROVIDE ACCESS INTERACTIVE TO AN INFORMATION SOURCE THROUGH A SYSTEM OF DISTRIBUTION BY NETWORK TECHNICAL FIELD The present invention generally relates to a system and method of access to provide interactive access to a source of information without the need to acquire hardware and software for expensive and difficult to use computers. More particularly, the present invention relates to a system and method for providing access to a source of information, such as the Internet, through a network distribution system, such as a television distribution system.

BACKGROUND OF THE INVENTION As is well known, "Internet" is a network of computers interconnected worldwide, access to which can be had for reasons of communication, research, entertainment and the like. However, such access normally requires the use of relatively expensive and complex equipment that includes a personal computer, and related hardware and software. In addition, the use of a personal computer and related equipment requires a relatively high degree of sophistication and commitment. Consequently, even if a user could buy a system that included a personal computer, a printer, a modem, cables and other necessary related equipment, the user would have to install, connect and properly configure each device, he would have to learn to use each device and would have to update the hardware and software as necessary to maintain the system. Accordingly, there is a need for an access system and method that is relatively inexpensive for the user, requiring only a minimum of technical sophistication commitment and that is relatively easy to use.

DESCRIPTION OF THE INVENTION The present invention satisfies the above need by providing a system and method for accessing a source of information, such as the Internet, through a network distribution system, particularly, a cable television distribution system. Conventional television distribution systems include a television distribution network that is interfaced through communication links (e.g., coaxial cables, optical fibers, wireless radio and satellite links, etc.) to a plurality of television sets of user. Typically, each user television is connected to a converter box or terminal or terminal that is interfaced between the communication link and the television to receive and decode the television signals that come from the distribution network. In the television distribution system employed in the preferred embodiment of the present invention, at least one upstream communication channel is provided between each user and the distribution network, which allows users to communicate in real time with the same. In addition, the television distribution network is interfaced with a source of information, such as the Internet, by means of an entry end server and router. A service provider, such as an Internet service provider (ISP), is typically employed to access the Internet, although direct access to the Internet can also be available. In case the source of information is Internet, each user can access the Internet by sending access commands and requests for information through the communication channel upstream to the endpoint server. The incoming end server then forwards the information requests of each user to the ISP. After the requested information is removed by the ISP, it is sent to the incoming end server which then drops it to the requesting user through a plurality of downstream television signal channels. In the preferred embodiment of the present invention, the information requested from the ISP can be downloaded to each user terminal. In an embodiment of the present invention, this is achieved by inserting the information in the vertical blanking interval (VBI) of the analog television signals that are transmitted concurrently by the television distribution network over the downstream channels. Alternatively, the information can be digitally encoded and packaged along with control information. Depending on the type of television distribution network, these packaged data are then used to modulate a selected carrier that is transmitted over the downstream channels, or the data is sent directly without additional modulation. In a cable television system, this insertion or encoding takes place at the input end of the network or cable. Accordingly, each converter box or terminal includes an extractor or decoder, and a terminal processor for extracting the information and formatting it for visual presentation on the user's television. A time division multiple access (TDMA) communication scheme is preferably employed in which the data transmitted through the upstream channels are packaged, and inserted into slots in the channels. This facilitates the transmission of data from multiple users through only one of the upstream channels. To provide an adequate synchronization of upstream channel data that will be transmitted from each user terminal to the distribution network, the terminal processor in each user terminal senses a vertical synchronization signal that is present in the current television signals below, and uses this signal to generate a TDMA framing signal to synchronize the transmission of upstream data. In another mode, the upstream data is packaged, but sent without a framing signal. Instead, the terminal processor continues to forward such data until such time as it receives acknowledgment from the entry end indicating that it has already been received. Therefore, the individual entry end server processes all requests for access and information on the Internet that come from each of the users connected to the television distribution network. To administer this arrangement, the present invention employs two remarkable features. First, to ensure that any user can quickly access the Internet, the incoming end server maintains a plurality of Internet browsing applications available by actively running at any given time so that a user requesting access to the Internet can immediately connect to it. through one of these available active browsers. This drastically reduces the entry time that is normally required to open the navigation application and access the Internet. To implement this feature of the invention, the inbound end server is programmed to keep open, at any time, a number of browsing applications in excess of those currently being used by users. The inbound end server monitors the number of available active browsers, and when the number falls below a certain predetermined number, the incoming end server causes additional browsing applications to open. Another significant feature of the present invention relates to the allocation of Internet Protocol (IP) addresses. In conventional Internet access systems, IP addresses are assigned either permanently or temporarily to each networked machine to facilitate communication between the Internet and the user. In the present invention, it is envisioned that a very large number (e.g., 1000) of television users would have the ability to access the Internet through a single end-of-entry server interfaced with the television distribution network. With this provision, it would be prohibitive to assign an IP address to each user. The present invention overcomes this problem by assigning a permanent ID address only to the incoming end servers that transmit all requests for Internet information to, and receive the requested information from, the Internet through the ISP. The entry end server must therefore include certain means to identify the user making each request, as well as the user to whom the requested information will be transmitted. This is achieved by providing each user terminal with a terminal identification number or code that is transmitted with each access request or information in conjunction with a session ID. Using the identification number or code, the incoming end server can keep track of which user requested the Internet information when it is received by the endpoint server from the Internet through the ISP.

BRIEF DESCRIPTION OF THE DRAWINGS The features and advantages of the present invention will become apparent from the following detailed description of preferred embodiments thereof, taken in conjunction with the accompanying drawings in which: Figure 1 is a block diagram of the structure of a system of access and a television distribution system constructed in accordance with a preferred embodiment of the present invention; Figures 2A and 2B are timing diagrams of channels downstream and upstream, respectively, of the television distribution system of Figure 1; Figure 3 is a block diagram of the input end server shown in the figural; Figure 4 is a block diagram of the cable entry end equipment shown in Figure 1; Figure 5 is a block diagram of the application server shown in Figure 3; Figure 6 is a block diagram of one of the converters or terminals shown in Figure 1; Figure 7 is a diagram of a downstream packet transmitted in one of the downstream channels shown in Figure 2A; Figures 8A and 8B are diagrams of payment charges that can be sent in the downstream package shown in Figure 7; Fig. 9 is a diagram of an upstream packet transmitted on one of the upstream channels shown in Fig. 2B; Figures 10A and 10F are diagrams of payment charges that can be sent in the upstream packet shown in Figure 9; Figure 11 is a flow diagram showing the recognition process carried out in the preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings in detail, where like numbers are used to indicate similar elements throughout, a preferred embodiment of an access system 10 is shown in Figure 1 to provide interactive access to a source of information through a television distribution system 11. As shown, the components of the access system 10 and the television distribution system 11 are by necessity mixed. Preferably, the television distribution system 11 is a cable television distribution system 11 comprising a nodal television distribution network 12 of branch lines of coaxial cable and / or optical fiber. As will be appreciated by one skilled in the art, said television distribution system 11 and network 12 are well known and widely used by cable television service providers throughout the United States. However, one skilled in the art will also recognize that other types of network distribution systems may be employed without departing from the spirit and scope of the present invention. Such other types of network distribution systems include but are not limited to in-orbit satellite systems, terrestrial wireless cable systems and the like. The television distribution network 12 has a network input end 14 and a plurality of terminal ends 16. As will be understood, and now referring to FIGS. 2A and 2B, the network 12 has a frequency spectrum that is divided into a plurality of downstream channels modulated by RF 20 (FIG. 2A) and a plurality of upstream channels modulated by RF 22 (FIG. 2B), wherein each downstream channel carries one or more television transmissions 24 from the input end of network 14 to terminal ends 16, and each upstream channel carries data transmissions 26 that come from terminal ends 16 towards the network input end 14. As illustrated in Figure 2A, each television transmission 24 over a channel respective downstream 20 according to a first embodiment of the present invention includes a plurality of sequentially transmitted image fields 28, wherein each of the image fields tr Answers 28 includes an image range 30 which corresponds to a transmission of pixelated image data, and a blank interval or vertical blanking interval 32 which corresponds to a transmission of non-pixilated image data. As is known, the blank interval 32 is necessary due to restrictions imposed by electronic cannon display devices. Most particularly, most television display devices employ an electronic cannon and a phosphorescent screen to visually display a television transmission 24, and an image from a transmitted image field 28 is created on the screen by focusing the electronic cannon to Shoot electrons on the screen in a series of horizontal lines applied sequentially from the top of the screen to the bottom of the screen. Accordingly, after the end of a first image field 28, a vertical erase interval 32 is required at the start of a second image field 28 to allow time for the electron gun to retrace from the bottom of the screen to the top of it. As is known, each transmitted image field 28 also includes a horizontal erase interval between each horizontal line transmitted to allow time for the electronic cannon to move back from the end of one line to the start of another line. As is also known, each image field 28 in the transmission convention of E.U.A. It is 1 / 60th. one second in temporal length T, and two image fields 28 combine to form an image frame. In another embodiment of the present invention, television transmissions are digitized, and include a plurality of digitally packaged data streams containing the required video, audio and control information that is sent directly or modulated for downstream transmission. It is understood that such techniques and apparatus for packaging, modulating and transmitting digital data streams are well known to those skilled in the art and do not require further description. As illustrated in FIG. 1, the network input end 14 of the television distribution system 11 is connected to a cable entry end 34, and the cable entry end 34 includes input end equipment or equipment. cable entry end distribution 36 and an entry end server 38. As will be described in more detail below, the entry end server 38 communicates with a source of information through a router 40 and a service unit of channel / data service unit (CSU / DSU) 42. Referring now to Figure 4, the cable entry end equipment 36 includes a conventional cable network entry end controller 44 for controlling the distribution of the television transmissions 24 over the respective downstream channels 20 of the television distribution network 12. For each downstream channel 20, the cable entry end equipment 36 can also include a codific optional video recorder 46 for receiving television transmissions 24 in the form of video programming and encoding video programming (only one video encoder 46 is shown in Figure 4). An RF 48 modulator is included in the cable input end equipment so that each downstream channel 20 modulates the respective television transmission 24 to the downstream channel frequency 20 (only one RF modulator 48 is shown in FIG. 4) , and a single RF 50 combiner receives the emissions of all Rf 48 modulators and combines these emissions to form a single signal. The emission of the individual signal coming from the combiner RF 50 is fed to a duplex filter 52 and then to the network input end 14. As will be understood, the duplex filter 52 also receives the upstream data transmissions 26 on the upstream channels 22 and separates said upstream data transmissions 26 to send them further upstream. Referring again to Figure 1, the television distribution system 11 also has a plurality of converters or terminals 54, each terminal 54 being interfaced with a terminal end 16 of the television distribution network 12 for receiving the transmissions of television 24 on the respective downstream channels 20. As will be understood, each terminal 54 facilitates the selection of the downstream channels 20 and is interfaced with a display device 56 for visually displaying the television transmission 24 carried on the selected downstream channel 20. Typically, the display device 56 is a tuneable television set, although one skilled in the art will recognize that a non-tuneable television monitor can also be employed. Having thus far described the television distribution system 11, the access system 10 will now be described. Referring still to FIG. 1, the access system 10 includes an input device 58 associated with one of the terminals 54 for entering the same a command for a source of information. As illustrated in Figure 6, the command input at the terminal 54 by the input device 58 is transmitted by an upstream transmitter 106 on an upstream channel modulated by RF 22 of the television distribution network 12 from the terminal 54 to the cable entry end equipment 36. Preferably, the information source is the well-known Internet communications network, and the entry end server 38 communicates with it through a provider such as a provider of information. Internet services (ISP) 60. However, it will be understood that the source of information may be a source of local information at the cable entry end 34, an email exchange, an exchange of a "chat room", the application server 68 itself, or similar. Referring again to Figure 4, all upstream channels 22 are received from the network input end 14 of the cable distribution network 12 in the duplex filter 52, are separated by the duplex filter 52 of the current channels down 20, and are forwarded to RF demodulators 62, an RF demodulator 62 for each upstream channel 22 (only one RF demodulator 62 is shown in Figure 4). Accordingly, the RF-modulated upstream channel 22 having the transmitted command is demodulated, and the command is forwarded to an upstream data receiver 64 which in turn forwards the received command to the incoming end server 38 (as illustrated in Figures 1 and 3). As an alternative, although not illustrated, the present invention may use alternative upstream channels, such as telephone and / or RF transmissions other than cable. With such alternatives, the transmitted commands can be routed either directly to the upstream data receiver 64, or through the RF demodulator 62 to the upstream data receiver 64, as required. The inbound end server 38 is associated with the cable entry end equipment 36 and is interfaced with the ISP 60. Accordingly, the inbound end server 38 transmits a command based on the command forwarded from the current receiver up 64 to the ISP 60 by means of the router 40 and the CSU / DSU 42. More specifically, and referring now to Figure 3, the entry end server 38 is preferably divided into a communications controller 66 and a server 68. The command coming from the upstream receiver 64 is received by the communication controller 66 and is then forwarded to the application server 68. As will be described more fully below, the communications controller 66 packs data downstream, unpacks data upstream, handles session requests coming from terminals 54, and otherwise performs functions necessary to maintain communications between the application server 68 and terminals 54. Referring now to Figure 5, the application server 68 includes a communication module 70 in communication with the communication controller 66 for interfacing the application server 68 and the communication controller 66. The command received from the controller communications 66 is forwarded to the communications module 70 and is then forwarded to a session manager 72. As will be understood, the session manager 72 manages multiple sessions of multiple terminals 54, and therefore maintains an association between the received command and the terminal 54 that originated the received command. More particularly, as will be described in greater detail in conjunction with Figure 9, each command or information request received by the session manager 72 includes an identification number or code to identify which of the terminals 54 sent the command or request . The session manager 72 keeps track of this information so that when the requested information is received from the ISP 60, the session manager 72 will know to which of the terminals 54 the information should be downloaded. It should be noted that the ISP 60 communicates only with the application server 68 within the inbound end server 38, and thus does not communicate directly with any of the terminals 54. This is an important feature of the present invention because it eliminates the need to assign Internet Protocol (IP) addresses to each of the terminals 54. Instead, the system 10 requires the assignment of only an individual IP address to the application server 68 to manage all access requests and information on the Internet that comes from each of the terminals 54. After a command is received from one of the terminals 54, the session manager 72 forwards it to one of several user agents 74, depending on the command and the current application . The user agents 74 include a plurality of browsers 75 to navigate through the ISP 60, an email agent to facilitate the sending of emails through the ISP 60, a chat agent to facilitate online chat sessions, and Similar. In response to a received command, a user agent 74 issues one or more additional commands based on the received command in a format not understandable by the ISP 60, and the issued commands are forwarded to the ISP 60 by means of a post office 76 , a cache machine 78, or deriving the mail office 76 and the cache machine 78. As will be understood, the mail office 76 facilitates the sending and receiving of electronic mail, and the cache machine 78 stores and forwards traffic in any address In addition, the cache machine 78 can keep track of the commands issued and store certain data if requested on a regular basis. As will also be understood, the post office 76 and the cache machine 78 can be derived when they are not required, that is, during an online chat session. As with user agents, post offices and caching machines are well known and therefore do not require a more detailed description. Another significant feature of the present invention is the provision of a plurality of browsers 75 in the application server 68.

The session manager 72 controls the activation of the browsers 75 so that at any given time, several of the browsers 75 that are not being used are activated by any of the users. The purpose of this provision is to ensure that a user can be connecting to the Internet without the delays to enter that normally occur during the opening of a navigation application. In this way, when the application server 68 receives a request from a user for the connection to the Internet, the session manager 72 immediately establishes the connection through one of the available active browsers 75. When the user sends a request to conclude the session on the Internet, the session manager 72 then causes one of the navigation applications 75 to be closed. Session manager 72 is programmed to monitor the number of active browsers 75 available. When users connect to the Internet through browsers 75, the number of available active browsers decreases. Once this number reaches a predetermined minimum, for example 3, then the session manager 72 causes a predetermined number, for example, 5, of the browsers 75 to be reactivated to ensure that an active browser is always available when a browser is received. request for Internet access from a user. Preferably, the application server 68 also includes a user database manager 80A and an associated user database 80 for managing user information of the access system. As will be understood, said information includes information about each user, certain characteristics and attributes associated with each user, information about the information frequently accessed for each user and the like. The application server 68 may also have a billing interface module 82A for the purpose of charging users the use of the access system 10. As will be recognized by one skilled in the art, the billing interface 82A may be connected to any of the a plurality of known accounting systems for billing purposes, including the accounting system for billing use of the television distribution system 11. Preferably, the application server 68 includes an interface 84 for enabling the application server 68 communicate with the source of information through any protocol that the source of information could expect. For example, if the information source is Internet, and the ISP 60 is used, the protocol would preferably be the TCP / IP protocol (transmission control protocol / Internet protocol) normally used to communicate on the Internet. However, depending on the sources of information, one skilled in the art will recognize that other protocols may be employed without departing from the spirit and scope of the present invention. Referring again to Figure 1, interface 84 in Figure 5 preferably communicates with ISP 60 via router 40 and CSU / DSU 42 associated with the cable entry end 34. As will be understood, the router 40 is connected to the interface 84 for routing / pipe data between the ISP 60 and the interface 84, and the CSU / DSU 42 is a service unit for interfacing the router 40 and the ISP 60. Both the routers and the CSUs / DSUs are well known and therefore no further description is necessary. In addition, one skilled in the art will recognize that other methods for interfacing the ISP 60 with the inbound end server 38 may be employed without departing from the spirit and scope of the present invention. In addition, one skilled in the art will also recognize that not all commands have to be forwarded to the ISP 60. For example, if the requested information is already available in the application server 68 on the cache machine 78 (a highly Internet page). requested, for example), it is not necessary to establish communication with the ISP 60 to procure the requested information. Also, if the command is a message that comes from a first terminal 54 to a second terminal 54 via the inbound end server 38 (as described below), no communication has to be established with the ISP 60. Once the ISP 60 has received a command, the ISP 60 preferably processes the command to produce information in response thereto. The information produced is transmitted by the ISP 60 to the input end server 38, and then has to be sent to the terminal 54 from which it originated to the corresponding command. Accordingly, and as illustrated in Figure 5, the information that comes from the ISP 60 is received in the application server 68 via the interface 84 and is forwarded through the post office 76 and / or the mail machine. cache 78 to the appropriate user agent 74. As will be recognized, depending on the source of information, the information that comes from the source of the information may not be in a compatible form for visual presentation on the visual display device 56 associated with the terminal 54. Most particularly, if the information source is Internet and the ISP 60 is used to access information about it, the information will possibly include graphics in a first graphic form (for example, a screen that has 640 pixels x 480 pixels x 256 colors), while the terminal 54 and display device 56 possibly expect the information to be in a second graphic form (for example 320 pixels x 220 pixels x 16 colors). Accordingly, the graphics portion of the information must be converted by a graphics processor 86 in communication with the cache machine 78. The operation of a graphics processor to convert graphics data from one form to another and does not require an additional description herein. The information that comes from the ISP 60 is forwarded by the user agent 74 to a terminal visual display manager 88. Preferably, the terminal visual display manager 88 is designed to minimize the actual amount of information that must be transmitted to the user. terminal 54. Accordingly, it is preferable that the terminal display manager 88 make screens on the application server 68 for visual display in the appropriate terminal 54, that the terminal display administrator 88 retain information on the screen that in that moment is being presented in the appropriate terminal 54, and that the terminal visual display manager 88 transmits only the information necessary to refresh portions of a screen that will be changed. The process of making screens for visual presentation by a screen producer or the like is well known and does not require an additional description here. As will be understood, transmitting only refreshed information can greatly reduce the amount of downstream information that must be sent to terminal 54, especially if only a small change in a screen is necessary. Preferably, terminal 54 is programmed to operate based on said refreshed information. The refreshed information coming from the terminal image manager 88 and other information coming from the application server 68 is forwarded to the communication controller 66 by means of the communication module 70. Referring again to figure 4, the communications controller 66 receives the forwarded information and in turn forwards said information to a data modulator 90. The data modulator 90 can be, for example, a vertical erase interval inserter (VBI), or a horizontal erase interval inserter (HBI). ), or a QAM modulator, with or without an accompanying RF modulator. As will be understood, one of the data modulators 90 is provided for each downstream channel 20 (only one modulator 90 is shown in Figure 4) to insert sequential portions of the information forwarded from the communications controller 66 in the television transmissions 24 of the channel downstream 20 respectively. Each data modulator 90 is interposed in a downstream flow between the cable input end controller 44 and a respective duplex filter 22. In addition, the downstream path may also include a video encoder 46, RF modulator 48 and RF combiner 50 in accordance with techniques and systems known to those skilled in the art. As appreciated by those skilled in the art, different data modulation schemes and techniques may be employed without departing from the spirit and scope of the present invention. Referring now to Figure 6, the terminal 54 includes an RF tuner 94 and a downstream data extractor 92. Most particularly, the RF tuner 94 is preset to tune and demodulate the downstream channel 20 having the television transmission 24 with the inserted information, and the data extractor 92 extracts the inserted sequential portions of the inserted information from the blank intervals 32 of the sequential image fields 28 of the demodulated television transmission 24. The information extracted is then forwarded to a processor terminal 96. Assuming that the equivalent baud rate of each blank line in a VBI is approximately 12.5K, and assuming that eight lines of each VBI are used by the access system 10 of the preferred embodiment of the present invention, would achieve an equivalent baud rate of 100K using the VB insertion technique! for information transfer. For even higher data rates, it will be understood that the information could also be interspersed through video and audio streams. Preferably, the inserted information sent downstream from the cable entry end equipment 36 is encoded and / or compressed by the terminal visual display manager 88 using well-known techniques to minimize transmission time. Preferably, the processor 96 includes software to perform the function of decoding and decompressing the cooled information encoded and / or compressed. Alternatively, the terminal 54 may include a decoding and / or decompression module 98 interposed between the data extractor 92 and the processor 96 for decoding and decompressing the cooled and / or compressed information before said information is presented to the terminal processor. 96. As illustrated in Figure 6, the terminal processor 96 may be associated with a memory 100 to facilitate the various processing functions carried out by it. Preferably, the terminal processor 96 and the memory 100 produce display information from the information extracted, and the display information is presented on the display device 56. Preferably, the information extracted includes the screens produced by the terminal visual display manager 88 of the application server 68. Preferably, and as illustrated in FIGS. 1 and 6, the input device 58 for entering the commands in terminal 54 is a computer-type keyboard 58. Accordingly , a user of the access system 10 can type commands of word, email and the like. Likewise, the keyboard 58 preferably includes a mouse device for moving a graphic pointer presented on the display device 56. Preferably, the mouse pointer image is made by the terminal processor 96 in the terminal (converter) 54 during an improved response time. An infrared (IR) transmitter 102 is provided to transmit key stroke signals from the keyboard 58 in the form of an IR transmission to an IR receiver 104 to receive the IR transmissions from the keyboard 58 and to forward the signals corresponding to the signals keystroke transmitted to terminal processor 96. However,, the keyboard 58 may be attached to the terminal 54 without departing from the spirit and scope of the present invention. Alternatively, the keyboard 58 can be replaced with a remote control device having directional buttons and an execution button. Said remote control devices are of the type typically employed with a terminal 54 in a television distribution system 11 for entering in the terminal 54 a selection of one of a plurality of downstream channels 20 for visual presentation on the display device 56. Regardless of the command source, terminal 54 transmits the command via the upstream transmitter 106 as a data transmission 26 on one of the upstream channels 22 of the television distribution network 12. In the access system 10 of the preferred embodiment of the present invention, the input end server 38 is a centralized processor for each of the plurality of terminals 54. Accordingly, the upstream receiver 64 may receive a plurality of commands entered from a plurality of the terminals 54 over one or more of the upstream channels 22 of the distribution network 12, and then forwarding the respective received commands to the inbound end server 38. As will now be understood, the inbound end server 38 transmits commands based on the respective forwarded commands to the ISP 60, and the ISP 60 transmits the information to the outbound end server. entry 38 in response to the respective forwarded commands. The data modulator 90 receives information based on the respective transmitted information from the input end server 38 and inserts sequential portions of the received information in at least one of the television transmissions 24, and each of the data extractors 92 at the respective terminals 54 extracts the respective inserted sequential portions of the information. Preferably, the inbound end server 38 which acts as a centralized processor for each of the plurality of terminals 54 allows terminal-to-terminal communications, at least between the terminals 54 in the television distribution system 11. As shown in FIG. will understand, in said communication, a message is sent from a first of the terminals 54 to the entry end server 38, and then it is routed by the entry end server 38 to a second of the terminals 54, thereby deriving the ISP 60. Preferably, the message is an email message or is a message transmitted during a chat section, or some other application that provides peer-to-peer communications. As will be better described in conjunction with FIGS. 7-1 OF, the upstream data transmission between the terminal 54 and the communications controller 66 is preferably implemented using a conventional time division multiple access (TDMA) scheme, in the which data is fragmented into packets that are multiplexed into slots in upstream channels 22. To implement a TDMA scheme, a synchronization or time regulation signal known as a TDMA framing signal is required to synchronize the transmission of data packets. . In the preferred embodiment of the present invention, the TDMA framing signal for each of the upstream channels 22 is conveniently obtained from the vertical synchronization signal which is present in the television signals on the downstream channels 20. In this manner, the terminal processor 96 is preferably programmed to detect the vertical synchronization signal in the downstream data received from the data extractor 92 or the decoding and decompression module 98, and generating a TDMA frame signal that is fed to the upstream transmitter 106. The TDMA framing signal makes it possible for the transmitter upstream 106 send its data packets through the upstream channel 22 at the appropriate time to ensure that the data does not interfere with upstream data coming from the other transmitters 54 that are transmitting on the same upstream channel 22. The using the vertical synchronization signal in this way to generate the upstream TDMA framing signal thus eliminates the need to generate a separate time regulation signal, and ensures that the upstream data transmissions coming from terminals 54 are synchronized with each other. The data transmission upstream and downstream between the terminal 54 and the communications controller 66 of the input end server 38 will now be described in greater detail with reference to FIGS. 7-10F. Preferably, each upstream channel 22 of the television distribution network 12 is multiplexed into a plurality of upstream slots 108, as illustrated in Figure 2B, where the temporal length T of each slot 108 equals temporal length. T of the image field 28, as illustrated in Figure 2A. Likewise, a plurality of the upstream channels 22 is preferably paired with each downstream channel 20. In the preferred embodiment of the present invention, up to four upstream channels 22 are paired with each downstream channel 20. Also, each terminal 54 in the system 10 is preferably assigned to at least one of the upstream slots 108 at any time. Referring now to Figure 7, each downstream data transition coming from the communications controller 66 of the inbound end server 38 is preferably in the form of at least one downstream pack 110. As illustrated in Figure 7 , the downstream packet 110 includes a cyclical redundancy check (CRC) value of 4 bytes based on the rest of the downstream packet 110, where the CRC value is used to detect any corruption of the data in the packet 110. The Use of CRC values is well known and therefore does not require additional description. The downstream pack 110 also includes four SND bytes (SND A - SND D), wherein each SND byte corresponds to an upstream channel 22 associated with the downstream channel 20 on which the downstream pack 110 is sent. SND byte contains a section ID of a transmitter (ie, a terminal 54) which is allowed to transmit data upstream in the next upstream slot 108 of the corresponding upstream channel 22. For example, if the byte SND B has a value of '1', then the terminal 54 to which the session ID was assigned can transmit in the next upstream slot 108 on the upstream channel 22 corresponding to 'B' . Preferably, if a particular SND byte has a value of zero, any terminal 54 is allowed to transmit in the next upstream corresponding slot 108, for example, to request a new session.

Each downstream pack 110 also has four recognition bytes (ACK A-ACK D), where each byte ACK corresponds to an upstream channel 22 associated with the downstream channel 28 on which the downstream packet 110 is being sent. As will be understood, each byte ACK is sent in response to the successful reception of data upstream on a respective upstream channel 22 in the upstream slot 108 above. Preferably, each ACK byte includes the session ID of the transmission terl 54 and a revision bit indicating whether the serial number of the upstream packet being recognized is an even or non-numbered number. The downstream packet 110 also has a two-byte packet serial number, followed by a multi-byte payload. Referring now to FIG. 8A, it is illustrated that a downstream data payload 112 includes a one-byte payload session ID to identify the session ID of the desired receiving terl 54 for the payload. , a two-byte length indicator, and the contents of the data that is being sent in the packet. As will be understood, although all terls 54 on the downstream channel 20 will receive all downstream packets 110, a particular terl 54 will ignore the contents of the data being sent in pack 110 unless the data payload 112 has a payload session ID corresponding to the session ID of terl 54. Preferably, a downstream packet 110 periodically has a payload of home handling 114 in lieu of a data payload 112, as illustrated in Figure 8B. As illustrated, the house management payload 114 includes four channel bytes, each channel byte identifying a respective upstream channel 22 of the four associated with the downstream channel 20 over which the current packet is being sent. below 110. Accordingly, if a terl 54 wishes to initiate a session in the access system 10, the terl 54 must listen on the downstream channel 20 for a home management package 114, and after receipt of said management package. can deter which upstream channels 22 are associated with the downstream channel 20. The terl 54 can then send a session request over one of the associated upstream channels 22. If the session requests were made recently and were executed by the communications controller 66, the home management payment load 114 also includes a number of session request acknowledgments (access) (LACKs). In particular, the house management payment charge 114 includes a one-byte indicator of the number of LACKs, followed by each LACK. As illustrated, each LACK includes a 'box ID' which corresponds to a unique terl ID number associated with a requesting terl 54, a one-byte session ID which identifies the requesting terl 54 during the session, an indicator of downstream two-byte channel indicating the downstream channel 20 to which the requesting terl 54 is to be tuned, and a channel indicator upstream of a byte indicating the upstream channel 22 in which the terl 54 must transmit. Referring now to Figure 9, the upstream data co from the terl 54 is sent in the form of an upstream packet 116. As illustrated, each upstream packet 116 includes a CRC value of 4 bytes, as with each downstream packet 110, a one-byte identifier having the session ID assigned to the terl 54 and a revision bit indicating whether the upstream packet 110 has an even number or a data length indicator of a byte that indicates the length of a payload upstream of multiple bytes in packet 116, and the payload. As illustrated in Figure 10A, the upstream payment load has a structure 118 that includes a two-byte length indicator and the contents of the payload. Figures 10B-10F are examples of the contents of several upstream payment charges. As illustrated in FIG. 10B, a session or entry request 120 that comes from a terminal 54 includes a one-byte flag, which means that the upstream packet 116 is an access request 120 and the single-box ID of the requesting terminal 54. As illustrated in FIG. 10C, an upstream recognition payload 122 includes a one-byte flag, which means that the upstream packet 116 is an upstream flag 122, a serial number of two bytes of the downstream packet 110 that is being recognized, and a one-byte acknowledgment (ACK) flag. Occasionally, an expected downstream data packet 110 is not received, or is received with a corruption or error. Accordingly, and as illustrated in FIG. 10D, an upstream packet 116 may have an upstream forwarding request payload 124 that includes a one-byte flag, which means that the upstream packet 116 is a request. of forwarding 124, and a two-byte serial number of the downstream packet 110 that must be forwarded. If the data being sent upstream by terminal 54 is a key stroke of a computer-type keyboard 58 or other input device 58, then upstream pack 116 has an upstream key-strike payload 126, as illustrated in FIG. 10E, which includes a one-byte flag, which means that the upstream packet 116 is a key-hit payload 126, and a two-byte keypad code. As will be understood, if the key stroke comes from a keypad 58, the key hit code includes information about whether a CTRL / ALT / SHIFT key is being pressed at the moment a key is hit. As previously described, the input device 58 preferably includes a mouse or mouse-type device, and the movements of the mouse are input to the terminal 54 and the access system 10 as commands. Accordingly, an upstream packet 116 may include in upstream mouse movement formation 128, as illustrated in FIG. 10F. The mouse movement information 128 includes a one-byte flag, which means that the upstream packet 116 is a mouse movement payload 128, a one-byte mouse hit code, a mouse X-coordinate of two bytes and a two-byte mouse Y coordinate. As will be understood, the one-byte mouse hit code includes information about whether or not a SHIFT / CTRL / ALT key is being pressed, and left, middle and right mouse button information. As will be readily appreciated by one skilled in the art, the particular structures of the upstream and downstream packages 110, 116 can be changed without departing from the spirit and scope of the present invention. For example, if only three upstream channels 22 are assigned to a downstream channel 20, only three SND bytes and three ACK bytes are needed in the downstream pack 110 (FIG. 7). Similarly, the fields in the packets 110, 116 may be added, deleted or changed in terms of structure or size. With the access system 10 as described above, a terminal 54 requests a session in the following manner. Preliminary, the terminal 54 is tuned to a downstream channel 20 on which the downstream packets 110 are being sent, and listens to a home management pack 114 (as illustrated in FIG. 8B) to determine which upstream channels 22 are associated with the downstream channel 20. A random channel is selected from the upstream channels 22, and an input request 120 (FIG. 10B) is sent in an upstream slot 108 that has not been preassigned by a respective SND byte (as illustrated in FIG. 7). If an input acknowledgment (LACK) is subsequently received (FIG. 8B) within a predetermined number of time periods T (corresponding to the length of an image field 28 (FIG. 2A) and to the length of an upstream slot (FIG. figure 2B)), the session request is successful. If not, a new downstream and upstream channel 20, 22 random can be attempted. In the unlikely event that two terminals 54 send a session request in the same upstream slot 108, the communication controller 66 will receive data that has crashed and no terminal 54 will receive a LACK. Preferably, each terminal 54 then waits for a random amount of time and attempts a second session request. The process is repeated until both session requests are handled by communications controller 66. Once entered, and after terminal 54 issues an upstream command, the terminal waits for a downstream packet 110 that has been addressed to the terminal 54 in response to the command. Preferably, each downstream packet 110 received checked to determine if the serial number of the packet is correct. If the serial number of the packet is incorrect, a resend request 124 is sent (figure 10D) with the packet serial number of the last packet that was successfully received. Preferably, the inbound end server 38 interprets a forward request 124 as a request to forward the packet 110 having the forward serial number and each packet 110 sent later. If a forwarding request 124 is sent several times without any result, or if a downstream packet 110 has not been received by the terminal 54 within a predetermined period of time, the terminal 54 may attempt to reconnect. Preferably, in an attempt to reconnect, the terminal makes a request for session 120 on a new downstream and upstream channel 20, 22. As mentioned above, each downstream packet 110 and upstream packet 116 is quickly recognized (ACKed ) by the receiver of the package, as illustrated in figures 7 and 10C. As will be understood, said fast ACKs are necessary to solve the noise problem (as mentioned above) and to provide real-time access to the ISP 60. Preferably, a packet sender waits up to two upstream slots 108 or image fields 28 to receive an ACK from a packet receiver. If an ACK is not received at this time by a terminal 54, the terminal 54 preferably forwards the upstream packet 116 for which recognition is sought. If a terminal 54 is forced to forward data a predetermined number of times, an attempt to reconnect is preferably made on new upstream and downstream channels 20, 22. It is preferable to employ the following method to send commands and receive information in the access system 10 as described above. In the method, and now referring to Figure 11, first data is input to the input end server 38 on one of the terminals 54 (step S1101), and is transmitted from the terminal 54 on an upstream channel 22 of the distribution network 12 (step S1102). The first transmitted data is then received on the upstream channel 22 of the distribution network 12 in the communication controller 66 of the input end server 38 (step S1 103), and a first acknowledgment (ACK) of the first received data it is transmitted from the input end server 38 on a downstream channel 20 of the distribution network 12 (S1 104). The first transmitted ACK is then received on the downstream channel 20 of the distribution network 12 at the terminal 54 (step S1 105) to indicate that the first entered data was received successfully. Preferably, the first ACK is received by the terminal 54 in approximately two image fields 28 or upstream slots 108 (2T). In the method shown in FIG. 1 1, second data is also transmitted from the communications controller 66 of the input end server 38 to a downstream channel 20 of the distribution network 12 (step S1 106) and are received by the terminal 54 (S1 107). In response, the terminal 54 transmits a second ACK of the second received data on an upstream channel 22 of the distribution network 12 (step S1 108), and the second ACK transmitted and received by the entry end server 38 (step S1 109) to indicate that the second data was successfully received by terminal 54. As will be understood, and as already described previously, each transmission step on a downstream channel 20 in the real-time recognition method described above includes the step of inserting sequential portions of information (ie, the second data or the first ACK) in the blank intervals 32 of sequential image fields 28 of at least one of the television transmissions 24, and each of the steps of reception on a downstream channel 20 includes the step of extracting the inserted sequential portions of the blank interval information 32 from the sequential image fields 28 of the television transmissions 24. In summary, the present invention comprises a new and useful system and access method for accessing information from a remote information source. The access system is particularly useful because it takes advantage of an existing network distribution system, because a user of the access system does not have to invest substantial resources in personal computers, modems and the like, because a user does not have to be technically sophisticated , and because a user does not need to occupy a telephone line to obtain said information. In addition, the equivalent baud rate of said access system is significantly higher than that available from a conventional telephone modem with a baud rate of 28.08K. Those skilled in the art will appreciate that changes can be made to the embodiment described above without departing from the inventive broad concepts thereof. For example, and as already mentioned previously, although the preferred embodiment of the invention is implemented by inserting information from the ISP 60 or other source of information in the vertical blanking interval of a conventional analog television signal, it should be understood that the invention it could also be implemented using a fully digital coding format, such as MPEG II, for example. Furthermore, it can be appreciated that a personal computer can be interfaced with the terminal 54 to provide improved access, while still being within the spirit and scope of the present invention. Moreover, although the preferred embodiment employs a television distribution system, the present invention can be implemented using any network distribution system, such as a radio transmission network, location network, etc. Therefore, it is understood that this invention is not limited to the particular embodiment described, but is designed to cover modifications within the spirit and scope of the present invention defined by the appended claims.

Claims (27)

NOVELTY OF THE INVENTION CLAIMS

1. - An access system for providing interactive access to a source of information through a network distribution system, comprising: a) a distribution network that includes a network input end, a plurality of endpoints, a plurality of downstream channels connected between said network input end and said terminal ends, and a plurality of upstream channels connected between said network input end and said terminal ends; b) a plurality of transmitters connected, one each, to said corresponding terminal ends, for transmitting commands through said upstream channels to said network input end requesting information from said information source, each of said commands includes a identification code that identifies one of said terminals that the command sends; and c) a server in interface between said network entry end and said information source, said server has an Internet Protocol address assigned thereto to facilitate communication with said information source; and includes means for sending a request for information to said source of information in response to a command coming from one of said terminals, receiving said requested information from said source of information, identifying from said identification code, one of said terminals that said command sent, and download said requested information through said end of network input and one of said channels downstream to said one of said terminals.

2. The system according to claim 1, further characterized in that said server further includes: 1) a plurality of navigation applications for concurrent use by a corresponding number of said terminals; 2) means for maintaining a number of said navigation applications in an active state, wherein said number exceeds the number of said navigation applications that are currently being used by said terminals; and 3) means for connecting one of said terminals to one of said active browsers when an access command is received by said server from said one of said terminals.

3. The system according to claim 2, further characterized in that said means for maintaining further comprise means for monitoring the number of available active navigation applications, and means for activating additional navigation applications when said number of available active navigation applications fall below a predetermined number.

4. The system according to claim 1, further characterized in that said upstream channels are multiplexed by time division, the data for said upstream channels being inserted as packets in said upstream channels.

5. - The system according to claim 4, further characterized in that said downstream channels carry television signals from said network input end, said signals include a vertical synchronization signal; and means are provided to employ said vertical synchronization signal to generate a frame signal for data on said upstream channels.

6. The system according to claim 1, further characterized in that said distribution network comprises a television distribution network, said source of information comprises the Internet, and said server is interfaced with an Internet service provider.

7. The system according to claim 6, further characterized in that said television distribution network further comprises a cable television distribution network.

8. An access system for providing interactive access to a source of information through a network distribution system, comprising: a) a distribution network that includes a network input end, a plurality of endpoints, a plurality of downstream channels connected between said network input end and said terminal ends, and a plurality of upstream channels connected between said network input end and said terminal ends; b) a plurality of transmitters connected, one each, to said corresponding terminal ends, for transmitting commands through said upstream channels to said network input end requesting information from said information source; and c) an interface server between said network input end and said information source, said server includes: 1) a plurality of navigation applications for concurrent use by a corresponding number of said terminals; 2) means for maintaining a number of said navigation applications in an active state, wherein said number exceeds in number of said navigation applications that are currently being used by said terminals; and 3) means for connecting one of said terminals to one of said active browsers when an access command is received by said server from said one of said terminals.

9. The system according to claim 8, further characterized in that said means for maintaining further comprise means for monitoring the number of available active navigation applications, and means for activating additional navigation applications when said number of available active navigation applications fall below a predetermined number.

10. The system according to claim 8, further characterized in that said upstream channels are multiplexed by time division, the data for said upstream channels being inserted as packets in said upstream channels.

11. The system according to claim 10, further characterized in that said downstream channels carry television signals from said network input end, said signals include a vertical synchronization signal; and means are provided to employ said vertical synchronization signal to generate a frame signal for data on said upstream channels.

12. The system according to claim 8, further characterized in that said distribution network comprises a television distribution network, said source of information comprises the Internet, and said server is in interface with an Internet service provider.

13. The system according to claim 12, further characterized in that said television distribution network further comprises a cable television distribution network.

14. An access system for providing interactive access to a source of information through a television distribution system, comprising: a) a television distribution network that includes a network input end and a plurality of endpoints terminals; b) a plurality of downstream channels connected between said network input end and said terminal ends for transmitting television signals from said network input end, said television signals each including a vertical synchronization signal; c) a plurality of upstream channels connected between said network input end and said terminal ends, said upstream channels being multiplexed by time division with each other; and d) means for employing said vertical synchronization signal to generate a frame signal for data on said upstream channels.

15. - A method for providing interactive access to a source of information through a television distribution system, comprising the steps of: a) providing a television distribution network that includes a network input end, a plurality of endpoints terminals, a plurality of downstream channels connected between said network input end and said terminal ends, and a plurality of upstream channels connected between said network input end and said terminal ends; b) providing a plurality of transmitters connected, one each, to said corresponding terminal ends; c) providing an interface server between said network input endpoint and said information source, said server has an Internet protocol address assigned thereto to facilitate communication with said source of information; d) transmitting a command from one of said terminals through one of said upstream channels to said network input end, said command requesting information from said information source and including an identification code identifying one of said terminals that send the command; e) forwarding said command to said server; f) sending a request for information from said server to said source of information in response to said command; g) send the requested information from said source of information to said server; h) identifying said identification code from one of said terminals that sent said command and i) downloading said requested information from said server through said end of the network input and one of said channels downstream to said one of said terminals.

16. The method according to claim 14, further comprising the steps of: j) causing said server to activate a plurality of Internet browsing applications for concurrent use by a corresponding number of said terminals and k) connecting said one of said terminals to one of said active navigation applications when said command is received by said server from said one of said terminals.

17. The method according to claim 16, further comprising the steps of: I) causing said server to monitor the number of said available active browsers that are not currently connected to one of said terminals and m) causing said server activate additional navigation applications when the number of active navigation applications falls below a predetermined number.

18. The method according to claim 15, further characterized in that said step of transmitting a command from one of said terminals through one of said upstream channels to said network input end further comprises: 1) forming said command as at least one data packet and 2) inserting said at least one data packet into at least one corresponding slot in said upstream channel.

19. The method according to claim 18, further comprising the step of: 3) employing a vertical synchronization signal in a television signal transmitted through one of said downstream channels as a frame signal to transmit said signal. at least one packet to said end of network input.

20. The method according to claim 15, further characterized in that said step of providing a distribution network further comprises providing a television distribution network, and said step of sending a request for information from said server to said source of information it further comprises sending a request for information from said server to an Internet service provider, and forwarding said request from said Internet service provider to the Internet.

21. The method according to claim 20, further characterized in that said step of providing a television distribution network further comprises providing a cable television distribution network. 22.- A method to provide interactive access to a source of information through a television distribution system, comprising the steps of: a) providing a television distribution network including a network input end, a plurality of endpoints, a plurality of downstream channels connected between said network input end and said terminal ends, and a plurality of upstream channels connected between said network input end and said terminal ends; b) providing a plurality of transmitters connected, one each, to said corresponding terminal ends; c) providing an interface server between said network input end and said information source, said server controlling the activation of a plurality of navigation applications; d) causing said server to activate a plurality of navigation applications; e) transmitting a command from one of said terminals through one of said upstream channels to said network input end, said command requesting information from said information source; f) forwarding said command to said server; g) connecting said one of said terminals to one of said active navigation applications, and sending a request for information from said server to said source of information in response to said command; h) sending requested information from said information owner to said server and i) downloading said requested information from said server through said network entry end and one of said channels downstream to said one of said terminals. 23. The method according to claim 22, further comprising the steps of: I) causing said server to monitor the number of said available active bros not currently connected to one of said terminals; and m) causing said server to activate additional navigation applications when the number of active navigation applications falls below a predetermined number. 24. The method according to claim 22, further characterized in that said step of transmitting a command from one of said terminals through one of said channels upstream to said network input end further comprises: 1) forming said command as at least one data packet and 2) inserting said at least one data packet into at least one corresponding slot in said upstream channel. The method according to claim 24, further comprising the step of: 3) employing a vertical synchronization signal in a television signal transmitted through one of said downstream channels as a frame signal to transmit said signal at least one packet towards said end of network input. The method according to claim 24, further comprising the step of: 3) repeatedly sending said at least one data packet to said network input end until a recognition is received from said input end of network, that said at least one packet has been received. 27.- A method to synchronize the transmission of data in a system to provide interactive access to a source of information through a television distribution system, which comprises the steps of: a) providing a television distribution network that includes a network input end and a plurality of endpoints; b) providing a plurality of downstream channels connected between said network input end and said terminal ends for transmitting television signals from said network input end to said terminal ends, each of said television signals including a synchronization signal vertical; c) providing a plurality of upstream channels connected between said network input end and said terminal ends for transmitting data from said terminal ends to said network input end; and d) multiplexing a plurality of data packets through said upstream channels by generating a frame signal for said data packets in response to said vertical synchronization signal in said television signals. SUMMARY OF THE INVENTION An access system and method provide interactive access to a source of information, such as the Internet, through a network distribution system, such as a television distribution system; each user of the television distribution system can access the Internet through an associated terminal by sending commands through an upstream channel to an input end server that is interfaced between a television network input endpoint and a Internet service provider; the incoming end server manages all requests for Internet information from the terminals by forwarding the requests to the internet service provider and receiving the required information from it; an Internet protocol address is assigned only to the entry-end server that keeps track of the terminals requesting information by means of terminal identification numbers or codes associated with each request; the entry end server also maintains a plurality of active Internet browsing applications all the time to ensure that a terminal requesting Internet access can be immediately put into an interface with the Internet service provider through one of the applications active navigation; each of the downstream television signals includes a vertical synchronization signal which is preferably used to generate a frame signal to synchronize the upstream transmission of the data packets containing the information requests coming from the terminals. J N / avc * ecm * jtc * eos * elt * P00 / 307F