KR20030096519A - Asymmetric Interactive Multicasting Packet Data Communication System and its method - Google Patents

Abstract

PURPOSE: A system for performing asymmetric bidirectional multicasting packet data communication is provided to loop-process unicasting packets received from a client's terminal, and to integratedly transmit the processed packets in multicasting packets, thereby supplying the same data in real time and enabling bidirectional communication. CONSTITUTION: A UDP server(237) receives a specific event, and carries out the event. Multicast sockets(235,255,273) transmit or receive packets in a multicasting system. The multicast socket(235) transmits multicasting packets. The multicast sockets(255,273) receive the multicasting packets. Controllers(233,253,271) control various streams in order to logically process the specific event, and maintain organic relations between modules.

Description

Asymmetric Interactive Multicasting Packet Data Communication System and its method

The present invention relates to bidirectional multicasting packet data communication on an asymmetric network. More specifically, the present invention relates to asymmetric bidirectional multicasting packet data that transmits unicasting packet data during uplink transmission, converts it to multicasting packet data, and then transmits the downlink transmission. It's about communication.

In general, packet transmission technology is divided into unicasting, broadcasting, and multicasting.

Unicasting is a one-to-one transmission technology. If there is a terminal that requests data and a server that provides data, the server has to bear the burden of providing data in response to each terminal that requests data. The server has the problem of instantaneous load on the CPU and network traffic.

Broadcasting is a technique of simultaneously transmitting the same type of data from a server to all terminals in the same network segment. This technology has the inherent problems of inefficiency of sending data to unwanted terminals and of not routing packets by routers.

Multicasting, on the other hand, is a one-to-many or many-to-many transmission technology that simultaneously transmits data to terminals that need data on the same network segment and even packet routing by routers. It is a very good packet transfer protocol technology for transmitting. However, multicasting also has many problems. That is, since the multicasting packet passes through the public Internet network, most of them are blocked at the router of the ISP (Internet Service Provider). Also, in the case of satellites, multicasting packets cannot be sent from the VSAT (Very small aperture terminal) terminal. There is a technical difficulty in maintaining the interactivity using casting. Therefore, it consists only of unidirectional products by multicasting tunneling.

Currently, RealAudio's Real Player or Microsoft's Windows Media Player are representative examples of typical multicasting applications that use unidirectional multicasting. The multicasting tunneling technique is used to transmit multicasting. Examples of using multicasting in a network.

On the other hand, the multicasting-based programs supporting the conventional two-way network targets only the network having the same network bandwidth in transmitting and receiving data. In other words, both the server side sending multicasting data and the client side receiving multicasting data in the same network as the LAN or intranet, rather than the public public Internet network, join the same group address. By joining, both the server side and the client side could freely send and receive.

However, asymmetric networks, in particular VSAT satellite networks, cannot implement bidirectional multicasting because they cannot directly join group addresses and transmit multicasting data directly from the VSAT stage to satellites. Also, for asymmetric networks such as ADSL or cable modems, interactive multicasting was not possible for similar reasons.

In particular, although there are many remote education solutions that are conventionally implemented on the Internet through unicasting methods, due to the limitations of unicasting, only a small number of users can be serviced at the same time. The market has not been able to meet the demands of the market that is expected to grow.

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide an asymmetric bidirectional multicasting packet data communication system and method capable of bidirectional communication under an asymmetric network having different up and down speeds.

1 is an overall block diagram of an asymmetric bidirectional multicasting packet data communication system according to the present invention;

2 is a process block diagram of an asymmetric bidirectional multicasting packet data communication system in accordance with the present invention;

3 is an explanatory diagram illustrating a process of converting a unicasting packet into a multicasting packet according to the present invention;

4 is a conceptual diagram of an internet broadcasting network to which the present invention is applied;

5 is a detailed diagram of an internet broadcasting network to which the present invention is applied;

6 is a block diagram of an Internet broadcast studio to which the present invention is applied.

<Explanation of symbols for the main parts of the drawings>

210: server 230: instructor module

250: Interrogator Module 270: Random Client Module

Hub system for asymmetric bidirectional multicasting packet data communication of the present invention for achieving the above object is a UDP server for receiving the unicast packet data transmitted from the first client terminal; A multicast socket converting the unicasting packet data transmitted from the UDP server into multicasting packet data and transmitting the multicast packet downward; And control means for controlling the UDP server and the multicast socket to operate organically.

In addition, the hub system for asymmetric bidirectional multicasting packet data communication of the present invention includes a UDP server for receiving the unicast packet data transmitted from the first client terminal; Data input means for receiving data for a multicasting packet; Converting the unicasting packet data transmitted from the UDP server into first multicasting packet data, converting multicasting packet data output from the data input means into second multicasting packet data, and first multicasting A multicast socket that combines packet data and the second multicasting packet data and transmits the downlink data; And control means for controlling the UDP server and the multicast socket to operate organically.

Preferably, the present invention further includes a TCP client for requesting a command for the first client-side terminal to transmit unicasting packet data in response to a specific control of the control means.

Preferably, the present invention further comprises a TCP server for outputting a command for the first client-side terminal to transmit unicasting packet data in response to the output of the TCP client.

Preferably, the multicast socket of the present invention extracts the data of the unicasting packet received upward, substitutes the data into a parameter of a conversion function to generate a header portion for the multicasting packet, and then combines the data. And generating a multicasting packet.

In addition, the client system for asymmetric bidirectional multicasting packet data communication of the present invention includes a multicast socket for receiving the multicast packet data transmitted downward; Data input means for receiving data for unicasting packet; A UDP client converting data output from the data input means into unicasting packet data and transmitting the data upwardly; And control means for controlling the multicast socket, the data input means, and the UDP client terminal to operate organically.

In addition, the asymmetric bidirectional multicasting packet data communication method at the hub side of the present invention includes a first step of receiving unicasting packet data transmitted from a first client terminal; And a second step of converting the unicasting packet data into multicasting packet data for downward transmission.

In addition, the asymmetric bidirectional multicasting packet data communication method at the hub side of the present invention includes a first step of receiving unicasting packet data transmitted from a first client terminal; A second step of inputting data for multicasting packets into the data input means; And converting the unicasting packet data into first multicasting packet data, converting multicasting packet data output from the data input means into second multicasting packet data, and converting the first multicasting packet data and the first data. And a third step of combining two multicasting packet data and transmitting the data downward.

Preferably, the present invention further comprises a fourth step of requesting a command for the first client-side terminal to transmit unicasting packet data.

Preferably, the present invention further comprises a fifth step of outputting a command for the first client-side terminal to transmit unicasting packet data.

In addition, the asymmetric bidirectional multicasting packet data communication method at the client side of the present invention includes a first step of receiving downlink multicast packet data; A second step of receiving data for a unicasting packet; And a third step of converting the unicasting packet data into unicasting packet data and transmitting the data upwardly.

The present invention transmits the unicasting packet data from the terminal on the client side to the multicasting engine dedicated to the multicasting process on the server side, and then converts the multicasting packet to the multicasting engine by the multicasting engine, and retransmits the data to the plurality of terminals on the client side ( Hereinafter referred to as 'looping unicasting') The multi-casting packet of the server side and the looped unicasting packet of the client terminal are combined and received by multicasting to the remaining client-side terminals. Enable communication.

Taking the distance learning system as an example, the present invention is as follows. When the server side sends the instructor's video, voice, and data to the users who are connected by multicasting packets, and at the same time, one of the many users who are being trained online in real time online such as the Internet, Sending questions (video) and content (voice) to the instructor as a looping unicasting packet allows the rest of the users in training to watch the multimedia communication between two points in real time, I can participate.

Hereinafter, the most preferred embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art can easily implement the technical idea of the present invention. .

1 is an overall block diagram of an asymmetric bidirectional multicasting packet data communication system in accordance with the present invention.

The system according to the present invention includes various contents of the presenter transmitting data, that is, a Windows application 110, a digitized video (H.263, etc.), voice 112 of the presenter transmitted for content description. And when various data such as high-resolution MPEG1 / 2/4 (114) containing real-time blackboard lectures or videos are delivered to the multicasting server engine 120 located on the server of the host, the multicasting server engine 120 sends the server the server. The multicasting packet 130 is converted into a multicasting packet together with the multimedia data on the side, and the converted multicasting packet 130 is transmitted through a network such as the Internet (140), and the user interface in which the transferred multicasting packet is played and drawn on the participant side terminal. 150, and any participant video and audio are transmitted to the unicasting packet 160 by the selection of the host or voluntary participation of the participant. It is fed back to the engine casting 120. The looping unicasting packet 160 is converted into a multicasting packet and retransmitted through the downlink network with the main multicasting multimedia data packets on the server side.

FIG. 2 is a process block diagram of an asymmetric bidirectional multicasting packet data communication system according to the present invention. The configuration of the present invention shown in FIG.

First, for convenience of description, a station generating multicasting data will be referred to as an instructor module, and a station receiving multicasting data will be referred to as a client module.

Looking at the main configuration of the present invention.

The TCP server 211 in the server 210 requests and performs a specific event using TCP, which is a reliable communication protocol mainly used for control communication, and may be located in the dedicated server 210. And may be configured together in the instructor module 230.

The TCP clients 239, 259, and 277 serve to request specific events to the server side using TCP, and are placed in the instructor module 230 and the client modules 250 and 270, respectively.

The UDP server (UDP Server 237) performs a specific event by using UDP, which is a communication protocol used to rapidly process multimedia packets, and the like, and may be placed in the instructor module 230, or may be placed in a dedicated server ( 210 may be placed.

The UDP client 257 serves to request a specific event to the server side using UDP, and is placed in each client module 250 and 270.

The multicast sockets 235, 255, and 273 transmit or receive packets by multicasting, and are placed in the instructor module 230 and each client module 250, 270, and in the instructor module 230. The multicast socket 235 serves to transmit the multicasting packet, and the multicast sockets 255 and 273 in each client module 250 and 270 serve to receive the multicasting packet.

The controllers 233, 253, and 271 of each module maintain the organic relationship between the respective component parts of the system and adjust the overall flow to logically process a specific event, and the instructor module 230 and the client modules 250 and 270 are controlled. The control unit is placed to meet the characteristics of each.

The database 213 stores overall information of subscribers and operators participating in or capable of participating in the communication connection.

The data generators 231 and 251 of each module generate data to be transmitted / received by multicasting, by reproducing images captured from a video camera, voices and sounds captured from a sound card, or those already recorded. Generates data and sends it to a multicasting socket.

In the system of the present invention having the configuration described above, the downlink transmission of the multicasting packet data is generally performed, and thus will be omitted. Hereinafter, transmission and reception of the looping unicasting packet will be described. In particular, any client 250 mutually transmits data transmitted by multi-casting various multimedia data (MPEG1 / 2/4, Windows Application Contents, H263 and voice) from the controller 233 of the instructor module 230. It is a process after permission or application for transmitting its own voice / video to the control unit 233 of the instructor module 230 through TCP communication via the TCP server 211 of the server 210 in order to communicate with each other.

When the control unit 233 of the instructor module 230 gives a command to the corresponding TCP client 239 to transmit the video / audio data to the specific client 250 (S201), the TCP client 239 requests The received video / audio data transmission request command of the specific client 250 is transmitted to the TCP server 211 of the server 210 (S203).

In response to the received command, when the TCP server 211 transmits a command for requesting video / audio data transmission of a specific client (questioner) through the TCP client 259 of the specific client 250 (S205), the TCP client 259 ) Transmits the received command data to the control unit 253 of the specific client 250 to read the command (S207).

Here, the steps S201 to S207 are steps that occur when the instructor gives the questioner an opportunity to ask a question, and thus are not necessarily required, and it is natural that the questioner can ask questions at any time.

If the read command is a command to transmit the video / audio data of the specific client 250, a UDP client 257 to be used for data transmission is generated (S209) and the data generator 251 is operated to operate the video / audio data. In operation S211, the UDP client 257 converts the generated video / audio data 251 into unicasting packet data (S213).

The UDP client 257 receiving the video / audio data of the specific client 250 transmits the video / audio data to the UDP server 237 (S215), and the UDP server 237 receives the video received from the UDP client 257. / Voice data is transmitted to the multicast socket 235 (S217), the multicast socket 235 extracts the data portion of the looping unicasting packet received from the UDP server of the instructor module and passes it as a parameter of the conversion function The multicasting packet is converted into the multicasting packet, and the multicasting packet data is transmitted to the multicast socket 273 of each client together with the multimedia data 231 generated by the instructor module 230 (S219). Meanwhile, in order to convert data into a multicasting packet, it is possible to convert the data using various types of conversion functions such as API functions that are used in the past.

The remaining client module 270 sends the multicasting packet data received on the multicast socket 273 to the data processing module (Draw / Play, 275) (S221), thereby real-time multimedia communication between the instructor and two specific client points to multicasting. You can watch.

On the other hand, unlike the distance education, since there are only a plurality of clients in conducting a remote multi-party conference or seminar, the data generation unit is unnecessary in the instructor module of FIG. 2, and the data transmission request of the instructor module is unnecessary. In addition, the type of data used herein does not necessarily include both voice and video, but may be data including both voice and video or both voice and video.

3 is an explanatory diagram illustrating a process of converting unicasting packet data into multicasting packet data according to the present invention.

When the interrogator video / audio data of the looping unicasting packet is received by the multicast socket 235 of the instructor module 230, the data part of the looping unicasting packet is extracted except for the header part when the unicasting packet is received in the same manner as the conventional method. By substituting into the parameter of the function, the header part for the multicasting packet is generated and combined with the data to generate the multicasting packet.

4 is a conceptual diagram of an internet broadcasting network to which the present invention is applied.

The Internet broadcasting studio to which the present invention is applied is connected with a cable TV local operator (SO) supporting high speed internet to implement various interactive services such as distance education, home shopping, auction, public hearing, culture center, seminar, investment presentation, etc. Show an example. The unicasting packet data sent by the subscriber is transmitted to the Internet broadcasting studio through the local cable TV station SO, and is converted into multicasting packet data in the internet broadcasting studio and transmitted to the entire subscriber in real time.

Here, a plurality of small circles placed on the circumference centering on the headquarters of the Internet broadcasting chain represents the distribution of Internet broadcasting studios by region, and the right side of the district A broadcasting studio is located near the local cable broadcasting station SO. By using a router to connect to the Internet, broadcast studio chain stores and subscribers conceptually show the connection.

Although FIG. 4 shows a connection with a local cable TV operator providing a cable modem service, it may be connected to a local company performing an ADSL service and play the same role.

5 is a detailed diagram of an internet broadcasting network to which the present invention is applied, and shows an embodiment in which an internet broadcasting studio is directly connected to a local operator backbone network or through a router.

FIG. 6 is a block diagram of an Internet broadcasting studio to which the present invention is applied. The Internet broadcasting studio may include a central control station 610 capable of centrally controlling all operations, a file captured by a video camera, or pre-recorded files in MPEG1 /. Server 620 that encodes and streams in multicasting to 2, broadcast video camera 630, server 640 that contains two-way multicasting sockets by looping unicasting, and records and streams all the contents broadcast in real-time two-way. Server 650 for converting a file to be a service, a server 660 containing various information of subscribers and operators and operating a management mode for maintaining a session, login processing of subscribers, online access and other general information processing. It is composed of a web server 670 containing a, and a server 680 for streaming MPEG4 to multicasting.

Since the present invention overcomes the limitations of one-way and interactive multi-casting is implemented, it can be effectively applied to local users such as real-time two-way distance education, seminars, and collaboration of local enterprise processes such as oil complexes for many users. have. In addition, the present invention allows broadcasting, home shopping, auctions, public hearings, etc., which are not limited to the participants, to be implemented under an asymmetric network environment such as VSAT satellite, ADSL, and cable modem.

In addition, the present invention can be used in symmetric networks such as LAN, wireless network, and WAN, and can be applied to various fields such as in-house broadcasting.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited to.

The present invention having the configuration as described above loops the unicasting packet received from the terminal of the client in an asymmetric network environment such as ADSL, cable modem, VSAT satellite, and transmits the multicasting packet in the same way regardless of the number of users in real time. In addition to providing data and enabling two-way communication, it is possible to provide high-quality two-way multimedia communication service to a large number of users in a limited network width and asymmetric network environment that is difficult to implement in unicasting or conventional multicasting. have.

Claims (11)

A UDP server for receiving unicasting packet data transmitted upward from the first client terminal; A multicast socket converting the unicasting packet data transmitted from the UDP server into multicasting packet data and transmitting the multicast packet downward; And Control means for controlling the UDP server and the multicast socket to operate organically Hub system for asymmetric bidirectional multicasting packet data communication comprising a. A UDP server for receiving unicasting packet data transmitted upward from the first client terminal; Data input means for receiving data for a multicasting packet; Converting the unicasting packet data transmitted from the UDP server into first multicasting packet data, converting multicasting packet data output from the data input means into second multicasting packet data, and first multicasting A multicast socket that combines packet data and the second multicasting packet data and transmits the downlink data; And Control means for controlling the UDP server and the multicast socket to operate organically Hub system for asymmetric bidirectional multicasting packet data communication comprising a. The method according to claim 1 or 2, A TCP client that requests a command for the first client-side terminal to transmit unicasting packet data in response to a specific control of the control means Hub system for asymmetric bidirectional multicasting packet data communication further comprising. The method of claim 3, A TCP server that outputs a command for the first client-side terminal to transmit unicasting packet data in response to the output of the TCP client Hub system for asymmetric bidirectional multicasting packet data communication further comprising. The method of claim 4, wherein the multicast socket, Asymmetrical bidirectional multi-characteristics comprising extracting data of a unicasting packet received upward, substituting the data into a parameter of a conversion function to generate a header portion for a multicasting packet, and combining the data to generate a multicasting packet. Hub system for casting packet data communication. A multicast socket for receiving the downcast multicast packet data; Data input means for receiving data for unicasting packet; A UDP client converting data output from the data input means into unicasting packet data and transmitting the data upwardly; And Control means for controlling the multicast socket, the data input means and the UDP client terminal to operate organically Client system for asymmetric bidirectional multicasting packet data communication comprising a. A first step of receiving unicasting packet data transmitted upward from the first client terminal; And A second step of converting the unicasting packet data into multicasting packet data for downward transmission Asymmetric bidirectional multicasting packet data communication method at the hub side comprising a. A first step of receiving unicasting packet data transmitted upward from the first client terminal; A second step of inputting data for multicasting packets into the data input means; And Converting the unicasting packet data into first multicasting packet data, converting multicasting packet data output from the data input means into second multicasting packet data, and converting the first multicasting packet data and the second A third step of combining downlinked multicasting packet data Asymmetric bidirectional multicasting packet data communication method at the hub side comprising a. The method according to claim 7 or 8, A fourth step of requesting a command for the first client-side terminal to transmit unicasting packet data Asymmetric bidirectional multicasting packet data communication method at the hub side further comprising. The method of claim 9, A fifth step of outputting a command for the first client-side terminal to transmit unicasting packet data Asymmetric bidirectional multicasting packet data communication method at the hub side further comprising. A first step of receiving downcast multicast packet data; A second step of receiving data for a unicasting packet; And A third step of converting the unicasting packet data into unicasting packet data and transmitting the data upwardly Asymmetric bidirectional multicasting packet data communication method at the client side comprising a.