KR100277826B1 - Multicast Service Operation System and Operation Method Using Satellite Channel - Google Patents

Abstract

The present invention relates to a multicast service operating system and a method using a satellite channel for providing a unidirectional or bidirectional multicast service to a terminal station using a satellite channel in a satellite internet network.

Multicast service operating system according to the present invention; The central station is a multicast service providing server that converts the service contents into IP datagrams using a multicast Internet Protocol address to provide a service, and a program allocated for the multicast IP address. A transmitter configured to receive the IP datagram and reconstruct it into a transport stream packet using an identifier (PID: Program Identifier) / table identifier (TID); When the subscriber wants to receive a specific multicast service, the terminal station receives the multicast service using a personal computer (PC) of the subscriber that generates information on the multicast service and information provided by the personal computer. And a set-top box for reconfiguring IP datagrams of transport stream packets received from the transmission unit of the central station according to the set PID / TID.

Description

Multicast Service Operation System and Operation Method Using Satellite Channel

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite internet system, and more particularly, to a multicast service operating system and a method for operating a multicast service using a satellite channel for providing a single station or a bidirectional multicast service to a terminal station using a satellite channel in a satellite internet network.

Currently, for individuals wishing to use the Internet, Internet access service providers offer services up to 28.8 Kbps in both directions via telephone modems. However, such a service transmission rate is insufficient to provide an internet service having various types of traffic characteristics. Accordingly, there is a need for a network capable of providing high-speed internet services, and development of a satellite internet system capable of providing internet services using a satellite internet network having broadcast characteristics and capable of high-speed transmission is required. .

Due to this demand, the development of satellite Internet system is being made, but the development of services is still insufficient. In particular, the satellite Internet network has broadband characteristics and, unlike the land network, consists of one network. That is, in the satellite Internet network, since all terminal stations are connected to one network (network), many terminal stations must share a limited satellite channel. Therefore, it is necessary to provide a service in a manner that uses the least number of satellite channels as possible according to the service characteristics to be provided.

In addition, while the terrestrial network can always use the transmission path permanently, the satellite Internet network has a very complicated routing problem to provide a multicast service because separate sub-networks constitute a network.

However, at present, there is no multicast service that can efficiently use the characteristics of the satellite Internet network, and there is no method for providing a multicast service. Multicast service is classified into paid service and free service according to the provided service, which means that a specific multicast service (that is, paid service) must be registered to subscribe to a service. do. In addition, the subscriber should be able to receive the corresponding multicast service without registering any more services already registered, and in this case, provide a one-way multicast service. Therefore, a method of providing a multicast service suitable for each service by analyzing the characteristics of a pay / free multicast service and a unidirectional / bidirectional multicast service should be provided.

Accordingly, the present invention has been made to solve the above-mentioned problems of the related art, and provides a multicast service to a plurality of terminal stations using a satellite channel based on MPEG-2 (Moving Picture Experts Group-2) in a satellite Internet network. An object of the present invention is to provide a multicast service providing method using a satellite channel for efficient provision.

1 is an overall configuration diagram of a satellite internet system to which the present invention is applied;

2 is a block diagram of a multicast service operating system using a satellite channel according to an embodiment of the present invention;

3 is a communication protocol configuration diagram of the multicast service operating system shown in FIG. 1;

4 is a block diagram of an MPEG-2 transport stream packet of the multicast service operating system shown in FIG. 1;

5 is a flowchart illustrating a multicast service registration processing method according to an embodiment of the present invention;

6 is a flowchart illustrating a multicast service deletion processing method according to an embodiment of the present invention;

7 is a flowchart illustrating a multicast service subscription application processing method according to an embodiment of the present invention;

8 is a flowchart illustrating a multicast service unsubscription processing method according to an embodiment of the present invention;

9 is a flowchart illustrating a multicast service providing processing method according to an embodiment of the present invention.

※ Explanation of code about main part of drawing ※

110: central station 111: terminal station

112: satellite 113: multicast service providing server

114: Internet 115: Multicast Service Management System

116 resource management system 117 transmission unit

118: network management system 119: set-top box

120: personal computer (PC)

In the multicast service operating system using a satellite channel according to the present invention for achieving the above object, in the multicast service operating system using a satellite channel having a central station and a terminal station for establishing a satellite Internet network,

The central station includes a multicast service providing server for converting the service contents into IP datagrams using a multicast Internet Protocol address to provide a service;

A transmitter that receives the IP datagram and reconfigures it into a transport stream packet using a program identifier (PID) / table identifier (TID) allocated for a multicast IP address. Including,

The terminal station, the subscriber's personal computer (PC) for generating information on the multicast service when the subscriber wants to receive a specific multicast service,

Setting a PID / TID for receiving a multicast service using information provided by the personal computer, and reconstructing an IP datagram with a transport stream packet received from a transmission unit of the central station according to the set PID / TID; It is characterized by including a set-top box.

In addition, the multicast service operating method using a satellite channel according to the present invention, in order to register a new multicast service,

To register a new multicast service,

A first step in which an operator configures a web page for handling subscription / unsubscription of a multicast service in a multicast service management system and stores a multicast client program;

A second step of an operator allocating multicast service information and a program identifier (PID) / table identifier (TID) and a program number necessary for transmitting the multicast service information and the multicast service information to a resource management system;

A third step in which the resource management system transmits the multicast service registration information to a transmission unit, and the transmission unit stores the multicast service registration information, and

And a fourth step in which the resource management system transmits the multicast service registration information to all terminal stations.

In addition, the multicast service operating method using a satellite channel according to the present invention, in order to delete the pre-registered multicast service,

A first step in which an operator deletes a web page that can handle subscription / unsubscription of a multicast service from a multicast service management system and deletes a multicast client program;

A second step of an operator deleting multicast service information and information necessary for transmitting the multicast service information from a resource management system;

A third step of the resource management system transmitting the multicast service deletion information to a transmission unit, and the transmission unit deleting the multicast service information using the transmitted information; and

And a fourth step in which the resource management system transmits the multicast service deletion information to all terminal stations.

In addition, the multicast service operating method using a satellite channel according to the present invention, in order to apply for subscription to the multicast service,

A first step in which a subscriber selects a multicast service to be provided on a screen of a personal computer;

A second step of connecting a channel between a terminal station and a central station if the multicast service is a service requiring subscription and is not currently subscribed;

A third step in which the personal computer connects a web page capable of handling the subscription / unsubscription of the multicast service stored in the multicast service management system,

A fourth step of the subscriber applying for the multicast service subscription to the multicast service management system through the web page, and

And a fifth step in which the multicast service management system and the personal computer record and store multicast service subscription information.

In addition, the multicast service operating method using a satellite channel according to the present invention, in order to cancel the subscription application for the paid multicast service,

A first step in which a subscriber selects a multicast service to be decommissioned on a screen of a personal computer;

A second step of connecting a channel between the terminal station and the central station;

A third step in which the personal computer connects a web page capable of handling the subscription / unsubscription of the multicast service stored in the multicast service management system,

A fourth step in which the subscriber requests to unsubscribe from the multicast service to the multicast service management system through the web page, and

And a fifth step in which the multicast service management system and the personal computer delete the multicast service subscription information.

In addition, in the method of operating a multicast service using a satellite channel according to the present invention, in order for a central station to provide a paid multicast service to a subscriber of a terminal station,

A first step of performing a multicast service providing program by the multicast service providing server;

A second step of transmitting, by the multicast service providing server, an encrypted service content to a set top box;

A third step of selecting a multicast service to be provided by a subscriber using a personal computer;

A fourth step of delivering, by the personal computer, request information for the selected multicast service to a set-top box;

A fifth step in which the set-top box extracts the service contents of the corresponding multicast service from the encrypted service contents provided from the multicast service providing server and provides them to the personal computer; and

And a sixth step in which the personal computer receives a service content by executing a multicast client program.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram of a satellite Internet system to which the present invention is applied. The satellite Internet system for providing Internet access is composed of a central station 110, a terminal station 111, and a multicast service providing server 113.

The central station 110 is composed of a transmission unit 117, a network management system 118, a resource management system 116, a multicast service management system 115, the Internet 114 and a multicast service providing server 113 Is connected to the terminal station 111 to provide the terminal station 111 with various types of Internet service and multicast service through the satellite 112. The terminal station 111 is composed of a set-top box 119 and a PC 120, and receives various types of services and multicast services through the central station 110 and the satellite 112.

2 is a block diagram of a multicast service operation system using a satellite channel according to an embodiment of the present invention, and shows the configuration of main systems of the central station 200 and the terminal station 201.

The central station 200 includes a resource management system 202, a multicast service management system 203, a multicast service providing server 204, a transmitter 205, a receiver 206, and a radio frequency (RF) unit ( 207). The multicast service providing server 203 transmits an IP protocol (Internet Protocol datagram) to the transmission unit 205 to provide a service. Receiving the IP datagram, the transmission unit 205 uses the program identifier (PID) and the table identifier (TID) assigned for the received multicast IP address to transmit the MPEG-2 trans. A port (TS: Transport Stream) packet is constructed and transmitted to all terminal stations 201 through the RF unit 207.

The set top box of the terminal station 201 is composed of an RF unit 208, a transmitter 209, a receiver 210, and a processor 211. When a subscriber wants to receive a specific multicast service, the personal computer (PC) 212 transmits information on the multicast service to the set-top box. The processor 211 of the set top box requests the receiver 210 to set a PID / TID for receiving a multicast service using the information requested by the PC 212. The receiver 210 processes the received MPEG-2 TS packet using the corresponding PID / TID, generates an IP datagram, and delivers the IP datagram to the processor 211. The processor 211 transfers the received IP datagram to the PC 212 through Ethernet.

The multicast service may be classified into a paid service and a free service. In the case of a paid service, the multicast service may be registered in the multicast service management system 203 to receive a service. The multicast service information registered by the subscriber is encrypted and recorded in the storage devices in the multicast service management system 203 and the PC 212. As a result, the registered service can be directly provided with the multicast service without a separate request to the central station 200, and illegal users can not be provided with the paid multicast service free of charge.

The multicast service management system 203 continuously transmits a transmission plan message to the terminal station 201 at regular intervals within the transmission period, and the terminal station 201 receiving the message receives a software (S / W) receiving program. Is performed. The multicast service management system 203 divides the software (S / W) into packets from the time of transmission, and transfers the divided packets to the transmission unit 205 in the form of IP datagram via Ethernet. At this time, the destination IP address of the IP datagram becomes a multicast IP address allocated for software (S / W) transmission. The transmitter 205 reconstructs the received packets into MPEG-2 TS packets using the PID / TID allocated for software (S / W) transmission, and then transmits them to the terminal station 201 through the RF unit 207. send.

The PC 212 reconstructs the received IP datagram into packets, and determines whether there is an error in the packets. If all packets are received without error, all packets are reconstructed into one file. The multicast service providing server 204 repeatedly processes the software (S / W) transmission process a predetermined number of times. As a result, the PC 212 may receive a packet not received within a specific period in the next period. The multicast service providing server 204 periodically transmits a transmission plan message to the terminal station 201, which receives the terminal station 201 executing a software (S / W) receiving program at any time within the transmission period. Let's do it.

3 is a communication protocol configuration diagram of the multicast service operating system shown in FIG. 1 and illustrates a communication protocol model between major systems required to provide a multicast service.

In order to provide a multicast service, the multicast service providing server 113, the multicast service management system 114, the resource management system 116, the transmission unit 117, the set-top box 119, and the PC 120 ). The multicast service providing server 113 includes a server program 301 for providing a multicast service, a UDP protocol 302 for reconstructing a UDP segment (User Datagram Protocol Segment), and an IP protocol for reconstructing a UDP segment into an IP datagram. 303 has a protocol structure composed of Ethernet 304 for reconstructing an IP datagram into an Ethernet frame.

The transmission unit 117 receives the Ethernet frame from the multicast service providing server 113 and reconfigures the IP datagram to the Ethernet 305, the IP protocol 307 to receive and process the IP datagram from the Ethernet 305, It has a protocol structure composed of MPEG-2 TS / CDMA (Code Division Multiplex Access) 306 that configures an IP datagram into an MPEG-2 TS stream. Here, the MPEG-2 TS / CDMA 306 receives the CDMA frame from the set top box 119 to generate an IP datagram, and the IP protocol 307 processes the IP datagram. In addition, the Ethernet 305 converts the IP datagram into an Ethernet frame and transmits it to the multicast service providing server 113.

The set-top box 119 is an MPEG-2 TS / CDMA 308 for receiving an MPEG-2 TS stream from the transmission unit 117 and generating an IP datagram, an IP protocol 309 for receiving and processing an IP datagram, It has a protocol structure consisting of Ethernet 310 to convert the received IP datagram into an Ethernet frame to process. Here, the Ethernet 310 receives an Ethernet frame from the PC 120, and the IP datagram received from the Ethernet 310 is processed in the IP protocol 309. MPEG-2 TS / CDMA 308 reconstructs the IP datagram into CDMA frames.

The PC 120 receives the Ethernet frame from the set-top box 119 and reconstructs the IP datagram into the Ethernet 311, the IP protocol 312 receiving and processing the IP datagram from the Ethernet 311, and the IP datagram. It has a protocol structure composed of a UDP protocol 313 for converting into a UDP segment, and a multicast client program 314 for receiving and processing a UDP segment received from the UDP protocol 313.

FIG. 4 is a configuration diagram of an MPEG-2 Transport Stream Packet (TS packet) of the multicast service operating system illustrated in FIG. 1, and has a structure of an MPEG-2 TS packet 400 used by the transmission unit 117. Indicates.

The MPEG-2 TS packet 400 is composed of a 4-byte TS header, a 3-byte PS header, and a 181-byte payload. There is a 13-bit PID field 403 in the PS header 401, and an 8-bit TID field 404 in the TS header 402, whereby one service channel is configured. There can be 256 (2 ⁸ ) distinct services per PID, and the total number of service channels that can be configured with such PID / TID is 2 ¹³ * 256.

Each multicast service uses independent PID / TID values. This information is information recognized by the transmitter 117 and the set-top box 119, the transmitter 117 is a PID / TID value assigned to the IP datagram having a multicast IP address among the received IP datagram After reconstructing the packet into the MPEG-2 TS packet, the packet is transmitted to the set-top box 119.

5 is a flowchart illustrating a multicast service registration processing method according to an embodiment of the present invention, and illustrates functions to be performed in each system when registering a new multicast service.

In order to register a new multicast service, the operator requests the multicast service management system 115 to register a new multicast service. The multicast service management system 115 constructs a web page that can handle subscription and release of the multicast service, and uses the multicast service used by the PC 120 to receive the multicast service. The cast client program is stored (step S100). In addition, the operator stores the multicast service information in the resource management system 116 and allocates a PID / TID and a program number necessary for transmitting the multicast service to be registered (step S101).

After the step S101 proceeds, the resource management system 116 transmits the multicast service registration information to the transmission unit 117, and the transmission unit 117 stores the received information (step S103). In addition, the resource management system 116 loads the multicast registration information in the system specific information (PSI / SI: Program Specific Information / System Information) of the program specification information and transmits it to all the terminal stations 111 (step S102).

The set top box 119 compares the version information of the item related to the multicast service from the received PSI / SI information (step S104). At this time, if the version is different, the PSI / SI table recorded therein is reconstructed (step S105), and the multicast service item information is transmitted to the PC 120. The PC 120 changes the PC screen by using the received multicast service information and provides a screen about the registered service to the subscriber (step S106).

6 is a flowchart illustrating a multicast service deletion processing method according to an embodiment of the present invention, and illustrates functions to be performed in each system when releasing a multicast service.

If the user wants to release a specific multicast service among the services that provided the multicast service, the operator requests the service release of the multicast service management system 115. The multicast service management system 115 deletes the web page associated with the multicast service and deletes the client program associated with the multicast service (step S200). In addition, the operator requests the resource management system 116 to release the service, the resource management system 116 deletes the corresponding multicast service information, and releases the PID / TID and program number assigned to the multicast service ( Step S201).

The resource management system 116 transmits the multicast service deletion information to the transmission unit 117. The transmitting unit 117 deletes the received multicast service information and releases the PID / TID information allocated for the multicast service (step S203). In addition, the resource management system 116 loads multicast deletion information on the PSI / SI and transmits it to all the terminal stations 111 (step S202).

When the PSI / SI information is received, the set-top box 119 compares version information of items related to the multicast service among the PSI / SI information (step S204). At this time, if the version is different, the PSI / SI table recorded therein is reconstructed (step S205), and the multicast service information is transmitted to the PC 120. The PC 120 changes the PC screen by using the received multicast service information, but does not show the screen about the deleted service to the subscriber (step S206).

7 is a flowchart illustrating a multicast service subscription application processing method according to an embodiment of the present invention, and illustrates functions to be performed in each system when a subscriber wants to receive a paid multicast service.

If the subscriber wants to subscribe to the paid multicast service, the subscriber selects the corresponding multicast service from the screen provided by the system using the PC 120 (step S300). The PC 120 determines whether the service selected by the subscriber is a service requiring subscription (step S301), and when the free service does not require registration, performs the multicast service providing processing method of FIG.

However, if a subscription is required, it is determined whether the service is already subscribed using the data stored therein (step S302). If the service is already subscribed, the multicast service provision processing method of FIG. Do this. On the other hand, in the case of a service not subscribed to in step S302, it is determined whether a return channel is currently configured for the own terminal station 111 to connect to the central station 110 (step S303). The connection control process is performed (step S304). If the connection is established, the PC 120 automatically connects to the corresponding multicast service subscription web page stored in the multicast service management system 115 via a web browser (step S305).

The subscriber subscribes to the multicast service through the web, and the multicast service management system 115 compares the received service subscription request information with the multicast service subscription information recorded in an internal database, and then subscribes to the service. The application result is transmitted to the PC 120 via the web (step S306). When the subscriber confirms the service subscription request result, the PC 120 transmits the service subscription request result confirmation information to the multicast service management system 115 through the Web and records the service subscription information in the internal storage device ( Step S307). The multicast service management system 115 records and stores service subscription information in an internal database using the received multicast service subscription application result confirmation information (step S308).

8 is a flowchart illustrating a multicast service subscribing processing method according to an embodiment of the present invention, and illustrates functions to be performed in each system when a subscriber intends to unsubscribe to a paid multicast service.

If the subscriber wants to unsubscribe the paid multicast service, the subscriber selects the corresponding multicast service release button on the screen provided by the system using the PC 120 (step S400). The PC 120 determines whether the service selected by the subscriber is a subscribed service using data stored therein (step S401), and if the service is not subscribed, terminates the service subscription release procedure.

However, in the case of a subscribed service, it is determined whether a return channel for connecting the own terminal station 111 to the central station 110 is currently configured (step S402). If connection of the return channel is required at this time, connection control processing is performed (step S403). However, if the connection is already established, the PC 120 automatically connects via the web browser to the corresponding multicast service unsubscribe web page stored in the multicast service management system 115 (step S404).

The subscriber subscribes to the multicast service subscription via the web, and the multicast service management system 115 compares the received service subscription release information with the multicast service subscription information recorded in the internal database, and then applies for service subscription cancellation. The result is transmitted to the PC 120 via the web (step S405). When the subscriber confirms the result of the service unsubscription application, the PC 120 transmits the service unsubscription application result confirmation information to the multicast service management system 115 through the web, and transmits the service subscription information recorded in the internal storage device. It deletes (step S406).

The multicast service management system 115 deletes the subscriber's multicast service subscription information from the internal database using the received multicast service subscription release result confirmation information (step S407).

FIG. 9 is a flowchart illustrating a multicast service providing processing method according to an embodiment of the present invention. When the multicast service is provided from the central station 110 to the terminal station 111, functions to be performed in each system are shown. Indicates.

The multicast service providing server 113 registered in the satellite internet network performs a multicast service providing program to provide a multicast service (S500). The content of the service is converted into an IP datagram using the assigned multicast IP address and then transmitted to the transmission unit 117. The transmitter 117 obtains the PID / TID value assigned to the multicast service from the received IP datagram (step S501), configures the MPEG-2 TS packet again, and sets the packet-converted content into the set-top box 119. (Step S502). At this time, the set-top box 119 does not receive the contents of the MPEG-2 TS packet having the PID / TID value without setting the PID / TID value in the demultiplexer.

The subscriber selects the corresponding multicast service item to be provided from the list of multicast services provided by the system (step S503). The PC 120 determines whether the corresponding service is a registered service by using the service subscription information stored in the internal storage device (step S504), and automatically processes the service subscription application of FIG. 7 when the service is not the subscribed service. Perform the procedure. In the case of a service applied for subscription, it is determined whether the corresponding multicast service is a bidirectional service (step S505).

In step S505, in the case of a bidirectional service, connection control processing is automatically performed to configure a bidirectional channel (step S506). When the channel configuration is completed, the PC 120 transmits the service request information to the set-top box 119 by using the program number for the corresponding service, and performs the corresponding multicast client program (S508).

The set top box 119 obtains a PID / TID value of the program number among the received service request information and sets the PID / TID value to the demultiplexer (step S507). After this, the set-top box 119 extracts the desired content from the MPEG-2 TS packet received from the transmission unit 117 using the set PID / TID value (step S509), and extracts the extracted MPEG-2 TS packet content. Is converted into an IP datagram (step S510). The set top box 119 delivers the converted IP datagram content to the PC 120, and the PC 120 delivers the received IP datagram content to the corresponding multicast program for processing (step S511).

In the case of a multicast service requiring a bidirectional channel, the subscriber configures a separate unicast channel to communicate with the multicast service providing server 113 (step S512).

As described above, the present invention varies the service providing method according to the characteristics of the multicast service in order to effectively provide various types of multicast services to numerous terminal stations through MPEG-2 based satellite channels. In particular, in the case of a paid multicast service, the subscriber can register the service in the multicast service management system and directly receive the corresponding multicast service without requesting the central station for the multimedia service that the subscriber applied for. Their multimedia services are easy to use, and illegal users have the effect of not being able to receive the paid multicast service.

Claims (16)

In a multicast service operation system using a satellite channel having a central station and a terminal station for constructing a satellite internet network, The central station, In order to provide a service, a multicast service providing server that converts the service content into an IP datagram using a multicast Internet Protocol address, A transmitter that receives the IP datagram and reconfigures it into a transport stream packet using a program identifier (PID) / table identifier (TID) allocated for a multicast IP address. Including, The terminal station, A subscriber's personal computer (PC) that generates information about the multicast service when the subscriber wants to receive a specific multicast service; Setting a PID / TID for receiving a multicast service using information provided by the personal computer, and reconstructing an IP datagram with a transport stream packet received from a transmission unit of the central station according to the set PID / TID; Multicast service operating system using a satellite channel, characterized in that the set-top box. The system of claim 1, further comprising a multicast service management system for managing paid multicast service information and subscriber information subscribed to the paid multicast service. The server of claim 1 or 2, wherein the multicast service providing server comprises: A server program for providing a multicast service, a UDP protocol for reconfiguring the contents of the multicast service into a User Datagram Protocol (UDP) segment, an IP protocol for reconfiguring the UDP segment into an IP datagram, and an Ethernet frame for the IP datagram. Reconfigured to have a protocol structure consisting of Ethernet provided to the transmission unit of the central station, The transmission unit, To process the Ethernet frame received from the multicast service providing server, the Ethernet frame received from the multicast service providing server is received and converted into an IP datagram, and the IP datagram to be transmitted to the multicast service providing server is converted to the Ethernet frame. An Ethernet protocol for converting the data into an Ethernet protocol; It has a protocol structure consisting of the CDMA protocol for receiving a Code Division Multiplex Access (CDMA) frame from a set-top box and converts it into an IP datagram, The set top box, MPEG-2 TS protocol for receiving MPEG-2 transport packets from the transmission unit and reconstructing them into IP datagrams, IP protocol for receiving and processing the IP datagrams, and receiving and reconstructing the IP datagrams into Ethernet frames. A protocol comprising an Ethernet frame reconstructed from the personal computer (PC) into an IP datagram and provided to the IP protocol, and a CDMA protocol configured to reconstruct an IP datagram to be transmitted to the transmitter into a CDMA frame Have structure, The personal computer (PC), Ethernet for receiving an Ethernet frame from the set-top box, an IP protocol for receiving and processing an IP datagram from the Ethernet, a UDP protocol for converting the IP datagram into a UDP segment, and a multicast for receiving and processing the UDP segment. Multicast service operating system using a satellite channel, characterized in that the protocol structure consisting of a client program. To register a new multicast service, A first step in which an operator configures a web page for handling subscription / unsubscription of a multicast service in a multicast service management system and stores a multicast client program; A second step of an operator allocating multicast service information and a program identifier (PID) / table identifier (TID) and a program number necessary for transmitting the multicast service information and the multicast service information to a resource management system; A third step in which the resource management system transmits the multicast service registration information to a transmission unit, and the transmission unit stores the multicast service registration information, and And a fourth step in which the resource management system transmits the multicast service registration information to all terminal stations. The method of claim 4, wherein the fourth step, A fifth step in which the resource management system loads multicast service registration information into program specification information / system information (PSI / SI) to a set-top box of a terminal station; A sixth step of the set-top box comparing version information of an item related to a multicast service in program specification information / system information; A seventh step of reconstructing the program specification information / system information table recorded therein and transferring the multicast service information to the personal computer when the version is different as a result of the comparison in the sixth step; and And an eighth step of displaying, by the personal computer, the screen for the registered multicast service by using the received multicast service information. To delete a previously registered multicast service, A first step in which an operator deletes a web page that can handle subscription / unsubscription of a multicast service from a multicast service management system and deletes a multicast client program; A second step of an operator deleting multicast service information and information necessary for transmitting the multicast service information from a resource management system; A third step of the resource management system transmitting the multicast service deletion information to a transmission unit, and the transmission unit deleting the multicast service information using the transmitted information; and And a fourth step of the resource management system transmitting the multicast service deletion information to all terminal stations. The method of claim 6, wherein the second step, The operator deletes the corresponding multicast service information from the resource management system and releases a program identifier (PID) / table identifier (TID) and a program number assigned to the multicast service. How to operate a multicast service. The method of claim 6, wherein the fourth step, A fifth step of the resource management system loading multicast service deletion information on program specification information / system information (PSI / SI) to a set-top box of a terminal station; A sixth step of the set-top box comparing version information of an item related to a multicast service in program specification information / system information; A seventh step of reconstructing the program specification information / system information table recorded therein and transferring the multicast service information to the personal computer when the version is different as a result of the comparison in the sixth step; and And an eighth step of erasing the screen for the deleted multicast service by using the received multicast service information by the personal computer. To apply for subscription to a paid multicast service, A first step in which a subscriber selects a multicast service to be provided on a screen of a personal computer; A second step of connecting a channel between a terminal station and a central station if the multicast service is a service requiring subscription and is not currently subscribed; A third step in which the personal computer connects a web page capable of handling the subscription / unsubscription of the multicast service stored in the multicast service management system, A fourth step of the subscriber applying for the multicast service subscription to the multicast service management system through the web page, and And a fifth step in which the multicast service management system and a personal computer record and store multicast service subscription information. The method of claim 9, wherein in the first step, If the multicast service selected by the subscriber is not a multicast service requiring subscription, or the subscriber is currently subscribed to the multicast service, And a sixth step of receiving a multicast service without applying for a multicast service subscription. In order to cancel your subscription to the paid multicast service, A first step in which a subscriber selects a multicast service to be decommissioned on a screen of a personal computer; A second step of connecting a channel between the terminal station and the central station; A third step in which the personal computer connects a web page capable of handling the subscription / unsubscription of the multicast service stored in the multicast service management system, A fourth step in which the subscriber requests to unsubscribe from the multicast service to the multicast service management system through the web page, and And a fifth step in which the multicast service management system and the personal computer delete the multicast service subscription information. The method of claim 11, wherein in the first step, If the subscriber is not subscribed to the multicast service selected, the multicast service operating method using a satellite channel, characterized in that it further comprises a sixth step of terminating the unsubscription process. In order for the central station to provide a paid multicast service to subscribers of the terminal station, A first step of performing a multicast service providing program by the multicast service providing server; A second step of transmitting, by the multicast service providing server, an encrypted service content to a set top box; A third step of selecting a multicast service to be provided by a subscriber using a personal computer; A fourth step of delivering, by the personal computer, request information for the selected multicast service to a set-top box; A fifth step in which the set-top box extracts the service contents of the corresponding multicast service from the encrypted service contents provided from the multicast service providing server and provides them to the personal computer; and And a sixth step of receiving, by the personal computer, a service content by executing a multicast client program. The method of claim 13, wherein the encryption process of the second step, A seventh step in which the multicast service providing server converts the service contents into an IP datagram using a multicast Internet Protocol address, and then delivers the contents to the transmission unit; And an eighth step of the transmission unit reconstructing the IP datagram into an MPEG-2 transport packet by using a program identifier (PID) / table identifier (TID) assigned to the multicast service and delivering the IP datagram to a set-top box. A method of operating a multicast service using a satellite channel. 15. The method of claim 13, further comprising a ninth step of connecting a bidirectional channel when the multicast service selected by the subscriber is a bidirectional service. The method of claim 13, wherein the fifth step, A tenth step in which the personal computer delivers the program number for the multicast service to the set-top box; An eleventh step of obtaining, by the set-top box, a program identifier (PID) / table identifier (TID) corresponding to the program number; A twelfth step of extracting service contents having the program identifier / table identifier among the encrypted service contents provided from the multicast service providing server and converting the service contents into an IP datagram; and And a thirteenth step of delivering the IP datagram to a personal computer.