KR100715667B1 - Device and method for forking stream using multicasting in media gateway system - Google Patents

Abstract

The present invention relates to a stream branching apparatus and method in a media gateway for providing HDTV services of various image quality from one service source.

In the media gateway system according to the present invention, a stream branching apparatus using a multicast method includes a transcoding module for outputting a plurality of output streams having different transcoding rates using HDTV stream input, and an output stream of the transcoding module. It is characterized in that it comprises a switching module for transmitting to the transcoding module again or to an external network.

According to the present invention, by transmitting one HDTV high-definition high-capacity streaming data at various streaming rates according to the network speed, the user can use a stream having a quality suitable for the user according to the internet situation. In addition, by sending various services by different multicast group addresses, there is an advantage of reducing network bandwidth waste.

Media Gateway, Multicast, Switching, Transcoding

Description

Stream branching apparatus and method using multicast method in media gateway system {DEVICE AND METHOD FOR FORKING STREAM USING MULTICASTING IN MEDIA GATEWAY SYSTEM}

1 is a diagram illustrating a network providing HDTV service according to an embodiment of the present invention;

2 is a detailed configuration diagram of a streaming branch apparatus using a multicast scheme according to an embodiment of the present invention;

3 is a multicast group address usage table according to an embodiment of the present invention;

4 is a flowchart of a multicast group address processing operation according to an embodiment of the present invention.

The present invention relates to a high definition television service (hereinafter referred to as "HDTV"), and more particularly, to a stream branching apparatus in a media gateway for providing HDTV services of various image quality from one service source; It is about a method.

In general, streaming refers to a technology capable of continuously and continuously processing data continuously transmitted over a network. These streaming technologies are of increasing importance as the Internet grows rapidly. In the case of downloading a large amount of multimedia files on the Internet, most of them do not have a fast connection line to download these large files immediately. In such cases, streaming technology makes the data available to the client side receiving the data even before all the files have been transmitted.

In order to provide HDTV-class streaming over the Internet, a technology for transmitting a large capacity of 19.2 Mbps through MPEG2 video compression technology has been created. However, in the current network situation, since there is no network capable of providing 19.2 Mbps of streaming, the service is provided with several different quality with one HDTV quality video. This technique is called transcoding technology. In other words, using transcoding technology, it is possible to provide a variety of services from 384 Kbps to 19.2 Mbps for the original video of 19.2 Mbps according to the network situation.

In the current network, a unicast technology for transmitting a low quality stream source through a network is used. However, when the unicast technology is applied, the user capacity is low, which makes it difficult to apply to a new technology that provides a large amount of streaming.

Therefore, IP multicast technology, which is a technology that does not use unicast between a source and a user and only broadcasts one stream until reaching an access router and finally broadcasts, is used.

 IP multicast technology joins a specific group through Internet Group Management Protocol (IGMP) using the D-class in the IP address range and the address from 224.0.0.1 to 239.255.255.255 as a group address from the client side. It is a technology that receives desired data. For such multicast, the server side sends a data packet with the aforementioned multicast group address as the destination address. The intermediate routers then send data to the registered multicast clients by checking whether they send data packets coming in through the multicast client-to-protocol protocol or sending a different route through packet copying. This multicast technology has the advantage of reducing the waste of bandwidth and infinitely increasing the capacity of the client.

However, the multicast technology does not provide a lot of services due to the following problems in the current network situation. In other words, once the multicast group is formed and the service is executed when the multicast technology is applied, even if one end user is registered in the multicast group, all users of the same LAN network can receive the service without charge. have. In addition, when multicast technology is applied, multicast is always performed to the place where multicast group users are located, thus increasing the amount of traffic in the network. In addition, regardless of the network speed to the end users, the same group is provided with the same speed only, there is a problem that can not provide a differentiated service.

Meanwhile, Korean Patent Application No. 10-2003-7007244 'Advanced Access Control for Video Delivery and Other Services, Network Access Unit and Service Provider Server' includes a channel request inspection unit and an authorization channel to stabilize service delivery through a regional access network. A method and apparatus are disclosed for providing stable multicast over a local access network by means of a network access unit having a list. Here the channel request from the subscriber is checked against the grant channel list and sent only if allowed. The authorization list is dynamically updated under headend control to prevent users from subscribing to or subscribing to services as required. However, in the above-mentioned invention, multicast streaming of one source to one channel for the security (security) when performing multicast, but does not solve the above-mentioned problems in the multicast application.

An object of the present invention for solving the above problems is to provide an apparatus and method for providing HDTV high-definition high-capacity streaming data at various streaming rates according to the network speed.

It is another object of the present invention to provide an apparatus and method for achieving an optimized switch function using a multicast function.

In order to achieve the above object, a stream branching apparatus using a multicast method in a media gateway system includes: a transcoding module configured to output a plurality of output streams having different transcoding rates using HDTV stream input; And a switching module for transmitting the output stream of the transcoding module to the transcoding module or the external network using a multicast group address.

In addition, in another media gateway system according to the present invention, in the stream branching apparatus using the multicast scheme, the transcoding module includes a plurality of transcoding engines, and each of the plurality of transcoding engines has a unique transcoding rate. A stream input to each transcoding engine is converted into the unique transcoding rate and provided to the switching module.

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Further, in another media gateway system according to the present invention, the stream branching apparatus using the multicast scheme is characterized in that the switching module is capable of inputting packets having a multicast group address as many as the number of the transcoding engines.

In another media gateway system according to the present invention, the stream branching apparatus using the multicast scheme is characterized in that the HDTV stream input is a stream of 19.2 Mbps.

In addition, in another media gateway system according to the present invention, a stream branching apparatus using a multicast method may include the switching module having a plurality of 10 / 100Mbps Ethernet input ports.

In another media gateway system according to the present invention, the stream branching apparatus using the multicast method is characterized in that the plurality of Ethernet input ports are divided into different groups according to the type of the HDTV stream input.

In addition, in another media gateway system according to the present invention, the stream branching apparatus using the multicast method is characterized in that the switching module has a 1 Gbps Gigabit Ethernet output port.

In addition, a stream branching method using a multicast method in a media gateway system according to the present invention for achieving the above object comprises: a first step of outputting a stream having a predetermined rate by a transcoding module to a multicast group address; A second step of determining, by a switching module, a type of the multicast group address; And transmitting, by the switching module, the stream to the transcoding module or an external network according to the multicast group address.

In addition, the stream branching method using the multicast method in another media gateway system according to the present invention, after the transcoding module generates a plurality of output streams having different transcoding rates by using the stream received from the switching module It further comprises a fourth step of providing to the switching module.

In addition, in another media gateway system according to the present invention, in the stream branching method using the multicast scheme, in the third step, if the multicast group address is designated to be transmitted to the transcoding module, the stream is transmitted to the transcoding module. Otherwise, the transmission to the external network.

Further, in another media gateway system according to the present invention, in the stream branching method using the multicast scheme, in the third step, a stream transmitted to the transcoding module and a stream transmitted to the external network may have different transcoding rates. It is characterized by having.

DETAILED DESCRIPTION A detailed description of preferred embodiments of the present invention will now be described with reference to the accompanying drawings. It should be noted that the same reference numerals and the same elements among the drawings are denoted by the same reference numerals and symbols as much as possible even though they are shown in different drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a diagram illustrating a network providing an HDTV service according to an exemplary embodiment of the present invention.

Referring to FIG. 1, an HDTV media gateway 100, an HDTV live camera 130, an MPEG2 encoder 140, an HDTV streaming server 150, and an external network 160 may be provided in a network providing HDTV service according to an exemplary embodiment of the present invention. , Routers 170, 171, and clients 180, 181, 182 exist. In addition, the stream branching apparatus 101 using the multicast scheme according to an embodiment of the present invention is configured in the HDTV media gateway 100, and the stream branching apparatus 101 includes a transcoding module 110 and a switching module ( 120).

The transcoding module 110 receives an input HDTV live stream or a stored HDTV stream as an input, and performs a function of changing the transcoding rate at various transcoding rates. In addition, the transcoding module 110 has a plurality of transcoding engines configured therein, and can generate a plurality of output streams having various rates by using one input stream.

The switching module 120 performs a multicast function by receiving a stream output from the transcoding module 110 and performs a switch function of transmitting a plurality of output streams through one output port. The input of the switching module 120 comes in through several 10/100 Mbps Ethernet (FastEthernet) input ports. Here, the HDTV stream source may be one or more, and in this case, the input Ethernet port may be divided into different groups according to the type of the HDTV stream source. And the output of the switching module 120 is made through a 1 Gbps Giga Ethernet output port.

The HDTV live camera 130 is an HDTV camera, and the output has a DVB / ASI interface. The output of the HDTV live camera 130 corresponds to a live broadcast video up to 1.485Gbps.

The output of the HDTV live camera 130 is processed by the MPEG2 encoder 140 into an MPEG2 image of 19.2 Mbps. The output interface of the MPEG2 encoder 140 has DVB / ASI, and the output stream is input to the transcoding module 110.

In addition, unlike the HDTV live camera 130, the HDTV streaming server 150 is responsible for delivering a stored stream source. The output of the HDTV streaming server 150 uses a DVB / ASI interface, and the output stream is input to the transcoding module 110 of the HDTV media gateway 100.

The external network 160 is an internet network having the plurality of routers 170 and 171. The end router 171 is directly connected to the clients 180, 181, and 182, and is a copy of the streaming.

Clients 180, 181, and 182 are user terminals that receive streaming services.

2 is a detailed configuration diagram of a streaming branch apparatus using a multicast scheme according to an embodiment of the present invention.

Referring to FIG. 2, the stream branching apparatus 101 using the multicast scheme according to the embodiment of the present invention includes a transcoding module 110 and a switching module 120. The transcoding module 110 has a plurality of transcoding engines 111 to 114 therein. In addition, the switching module 120 has a multicast switching module 121 therein.

Hereinafter, the functions and operations of the stream branch apparatus 101 using the multicast scheme according to the embodiment of the present invention will be described. The transcoding engines 111-114 of FIG. 2 each have a unique transcoding rate and are responsible for converting the source streams coming into the input into their respective unique transcoding rates. Accordingly, the transcoding engines 111 to 114 may output streams having various streaming rates.

In particular, unlike the other transcoding engines 2, 3, and 4 (112, 113, and 114), the transcoding engine 1 111 may be configured to output the input MPEG-2 19.2 Mbps stream 200 as it is. . The MPEG-2 19.2 Mbps stream 200 corresponds to a transport stream (TS), and the TS stream 200 is converted to a 19.2 Mbps Packetized Elementary Stream (PES) 220 through the transcoding engine 1 (111). Is converted.

Then, the multicast switching module 121 receives the output stream 220 of the transcoding engine 1 111 and then branches to the transcoding engines 2, 3, 4 (112, 113, 114) to input the stream 221, 222, 223. Can be provided. In addition, the multicast switching module 121 may perform an external stream output 224.

The transcoding engines 2, 3, 4 (112, 113, 114) use the same stream inputs (221, 222, 223) to output (230, 231, 232) streams with different transcoding rates, respectively.

Thereafter, the multicast switching module 121 outputs the stream outputs 233, 234, and 235 as it is, the streams 230, 231, and 232 received from the transcoding engines 2, 3, and 4 (112, 113, and 114). In the embodiment of the present invention, four transcoding engines 111 to 114 are configured, but a larger number of transcoding engines and various streaming rates can be provided.

3 is a table of multicast group address usage according to an embodiment of the present invention.

2 and 3, first, the multicast group address 229.0.1.1 (300) receives the multicast address from the switching module 120, and outputs to the other transcoding engines 112, 113, and 114 as well as the output to the external network. An example of an address that gives input. That is, when the stream 220 having the multicast group address 229.0.1.1 (300) is input from the transcoding engine 1 111 to the switching module 120, the switching module 120 replaces the input stream 220 with another. It transmits to the transcoding engines 112, 113, 114, and also to the external network 160.

Among the IP multicast group addresses in Fig. 3, 229.0.1.2 to 229.0.1.4 (301, 302, 303) are addresses of outputs of the transcoding engines 112, 113, and 114, respectively. When the outputs of the transcoding engines 112, 113, and 114 are input to the switching module 120, the switching module 120 outputs all streams having addresses of 229.0.1.2 to 229.0.1.4 (301, 302,303) without an internal multicast. Switch to the network 161 and output. As such, the streams 224, 233, 234, and 235 output from the switching module 120 have various streaming rates 320 to 323 and 330 to 333, and the user has a stream having a quality suitable for the user according to the internet situation. Can be received and used.

IP multicast group address 229.0.1.1 300 of FIG. 3 is for HDTV live broadcast service 340 from HDTV live broadcast camera 130. And IP multicast group address 229.0.2.1 (310) is an example of an address for servicing 341 input from streaming storage server 150. And streaming rates (Mbps) 320 to 333 are examples of transcoded stream rates carried in each multicast group address 300 to 303 and 310 to 313.

4 is a flowchart of a multicast group address processing operation according to an embodiment of the present invention.

The multicast group address processing operation according to the embodiment of the present invention is performed by the multicast switching module 121. Referring to FIG. 4, first, in step 401, the multicast switching module 121 receives and inputs a packet having a multicast group address from the transcoding module 110 (step 401). Here, the multicast switching module 121 may receive packets as many as the number of transcoding engines 111 to 114 of the transcoding module 110. In addition, the transcoding engines 111 to 114 may add as many packet receptions as the switching module 120 can support. In this case, the multicast group addresses 300 to 313 of FIG. 3 also increase.

The multicast switching module 121 then checks whether the multicast group address of the received packet belongs to the internal multicast group address (step 402). Herein, the internal multicast group address refers to an address where the stream received by the multicast switching module 121 is used as another input of the transcoding engines 2, 3, and 4 (112 to 114). That is, 229.0.1.1 (300), which is an example of FIG. 3, refers to a 229.0.2.1 (310) that receives an input from the HDTV stream server 150 or a 229.0.1.1 (300) multicast group address.

As a result of the determination in step 402, if the multicast group address of the received packet belongs to the internal multicast group address, multicasting is performed to all ports connected to the group (step 403). That is, not only the stream inputs 221, 222, and 223 that enter the transcoding engines 2, 3, 4 (112 to 114) from the multicast switching module 121, but also the output streams connected to the outside from the multicast switching module 121 ( 224).

However, if the multicast group address of the received packet does not belong to the internal multicast group address as a result of the determination in step 402, the multicast group does not connect to the internal port but multicasts to the external output port (step 404).

The stream branching method using the multicast method in the media gateway system according to the present invention can be embodied as computer readable codes on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, and also include those implemented in the form of carrier waves such as transmission over the Internet. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims below, but also by those equivalent to the claims.

According to the present invention as described above, by delivering a single HDTV high-definition high-capacity streaming data at various streaming rates according to the network speed, the user can receive and use a stream having a quality suitable for the user according to the Internet situation .

In addition, according to the present invention, by using the multicast function in the media gateway server having a transcoding module and a switch module, not only can the performance of the transcoding module be improved, but also the performance of the switching module can be improved. There is this.

In addition, according to the present invention by sending various services by different multicast group address, there is an advantage of reducing network bandwidth waste due to the existing unicast.

Claims (12)

A transcoding module for outputting a plurality of output streams, each having a different transcoding rate, using an HDTV stream input; And And a switching module for transmitting the output stream of the transcoding module to the transcoding module or the external network using a multicast group address. The transcoding module of claim 1, wherein the transcoding module comprises a plurality of transcoding engines, the plurality of transcoding engines each having a unique transcoding rate and the streams input to the respective transcoding engines. Stream diverter using a multicast scheme in a media gateway system, characterized in that the conversion to the coding module to the switching rate. delete The method of claim 3, wherein the switching module, And as many as the number of transcoding engines, input a packet having a multicast group address. The method according to any one of claims 1 to 4, The HDTV stream input is a stream branch device using a multicast method in the media gateway system, characterized in that the stream of 19.2Mbps. The method according to any one of claims 1 to 4, The switching module has a plurality of 10 / 100Mbps Ethernet input port stream diverter using a multicast method in a media gateway system. The apparatus of claim 6, wherein the plurality of Ethernet input ports are divided into different groups according to the type of the HDTV stream input. The method according to any one of claims 1 to 4, The switching module is a stream branch apparatus using a multicast method in a media gateway system, characterized in that the 1Gbps gigabit Ethernet output port. Outputting, by the transcoding module, a stream having a predetermined rate to a multicast group address; A second step of determining, by a switching module, a type of the multicast group address; And And a third step of transmitting the stream to the transcoding module or an external network according to the multicast group address in the switching module. The method of claim 9, wherein the transcoding module further comprises a fourth step of generating a plurality of output streams having different transcoding rates by using the stream received from the switching module, and providing the output stream to the switching module. Stream branching method using a multicast method in a media gateway system, characterized in that. The method of claim 9 or 10, wherein the third step, And transmitting the multicast group address to the transcoding module if the multicast group address is specified to be transmitted to the transcoding module. Otherwise, the multicast group address to the transcoding module. The method of claim 9 or 10, wherein in the third step, The stream branching method using the multicast method in the media gateway system, characterized in that the stream transmitted to the transcoding module and the stream transmitted to the external network have different transcoding rates.

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