KR20040067640A - Method for transmitting and receiving multiple channels in home network system - Google Patents

Abstract

PURPOSE: A method for transceiving a multi-channel in a home network system is provided to enable a server to re-encode an SPTS(Single Program Transport Stream) relative to more than one channel in response to more than one program request signal, and to generate an MPTS(Multi Program Transport Stream) to transmit the MPTS to a client, so that plural TVs can simultaneously receive a multimedia service. CONSTITUTION: If a session setup request is received from one of plural connected TVs, a set top box checks whether a TV is currently serviced(302). If not, the set top box transmits a session setup request message to a server(304). The set top box waits for a response to the session setup request(306). If the server responds to the session setup request, the set top box sets a session with the server(308). The TV can receive a desired service from the server.

Description

Multi-channel transmission and reception method in home network system {METHOD FOR TRANSMITTING AND RECEIVING MULTIPLE CHANNELS IN HOME NETWORK SYSTEM}

The present invention relates to a home network, and more particularly, to a multi-channel transmission / reception method in a home network system for providing a multimedia service to a subscriber.

Typically, at home, information devices such as PCs (Personal Computers), communication devices such as telephones, broadcasting devices such as TVs (Television), AV (Audio and Video) devices including digital video disc (DVD) players or digital cameras, Various devices such as home appliances are used. As described above, a home network is emerging as a technology for connecting a variety of devices used at home to form a network and interworking with various external networks to enable a user to conveniently use. Such home networks have been proposed in various forms.

The home network is attracting attention as a technology representing the 21st century, and multimedia technology, especially digital broadcasting, is at the center of the home network configuration. Unlike conventional analog broadcasting, digital broadcasting not only improves the quality of video / audio through digitized data transmission, but also provides information desired by the receiver out of the one-way broadcasting form from the broadcaster to the receiver. It is pursuing a form of interactive broadcast that may require.

For these home networks, DSMCC (Digital Storage Media Command and Control) is a client-server remote control protocol that can be controlled by a video server by a client for services such as VOD. In other words, the DSMCC format is a standard adopted for use in multimedia networks. 1 shows the structure of this DSMCC.

In the remote VOD server structure, the functions of DSMCC can be classified into user-network (UN) and user-user (UU) network. The UU is a client-server structure containing objects and APIs. The UN is a collection of messages that includes configuration, session control, inetwork resource management, and download. These messages are exchanged between the server, the client, and Session & Resource Management (SRM). The Advanced Television Systems Committee (ATSC) mainly quotes the DSMCC's UN download protocol and functions. DSMCC also provides a way to manage the namespace of streams and other objects. In other words, DSMCC allows you to find an object of interest through a naming layer, which connects to a menu of categories on the client. Initial service is performed using UN protocol. First, it sends configuration message to Session & Resource Management (SRM) by using meaningful address system such as IP. The UN message sent to the SRM is sent to the SG object (Service Gateway), which starts the VOD service or starts the naming service.

Specifically, the DSM-CC defines a series of message formats and session commands for communication between the client user 10, the server user 11, and the network resource manager 12. Communication between the client and server is established by a series of sessions, and messages are communicated between the user (client 10 or server 11 and network manager 12) to configure the client and / or server for communication. Exchanged. These messages are formatted according to the DSMCC UN (User to Network) protocol. Once the communication links are made, the messages are continuously exchanged between the client 10 and the server 11 according to the DSMCC UU (User to User Protocol).

As such, messages are exchanged between a user and a client through SRM (Session & Resource Management) in DSMCC. A system for connecting a server and a client without going through the SRM is being developed. However, although a system for single channel bidirectional communication between a user and a client in a remote multimedia service has been proposed, a system for multichannel bidirectional communication has not yet been discussed. Therefore, there is a need to provide a transmission / reception method for multiple channels supported by DSMCC.

Accordingly, an object of the present invention is to provide a bidirectional multi-channel transmission and reception method in a home network.

1 is a view showing the structure of a DSMCC,

2 is a block diagram of a home network system according to an embodiment of the present invention;

3 is a diagram illustrating a protocol stack structure of an integrated home network system according to an embodiment of the present invention;

4 is a diagram illustrating a control request and a response made on a CCP between a server and a client according to an embodiment of the present invention;

5 is a control flowchart when a session establishment request is received from a TV to which a set-top box as a client is connected according to an embodiment of the present invention;

6 is a control flowchart when a session release request is received from a TV to which a set-top box as a client is connected according to an embodiment of the present invention.

According to an aspect of the present invention, there is provided a multi-channel transmission / reception method for a home network, comprising: a client establishing a session between a server providing a multimedia service and a client connected to a plurality of TVs; Multiplexing a program request signal and transmitting the same to the server; the server re-encodes a single program transport stream (SPTS) corresponding to one or more channels in response to the one or more program request signals, Generating a program transport stream) and transmitting the same to the client.

The present invention provides a Channel Change Protocol (CCP) for broadcasting transmission through a network based on DSMCC. Unlike DSMCC, this CCP establishes a direct session between the server and the client through TCP / IP without going through Session & Resource Management (SRM), which enables session control and channel selection on a single protocol stack. The present invention provides a CCP for a Multi Program Transport Stream (MPTS) developed to simultaneously control multiple channels in one set top box (STB).

According to the present invention, when a request for receiving two or more broadcasts is received in one set-top box, a broadcast received through one network line has a form of MPTS. That is, the MPTS is generated by re-encoding the corresponding Single Program Transport Stream (SPTS) at the system level for the required multiple channels and transmitted to the set-top box. When the set-top box receives the MPTS (Multi Program Transport Stream) according to the present invention, it provides one transport stream (TS) requested by each terminal to one or more connected terminals. The set-top box multiplexes one or more program request signals requested by the terminal according to the present invention and transmits the same to the access network.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

2 is a block diagram of a home network system according to an embodiment of the present invention, in which a service provider 100, an access network 102, and a settop box 130 serving as a client are provided. It consists of the subscriber's house (104). The service providing system 100 includes an HDTV broadcasting encoding apparatus 108, a VOD server 110, and a RAS 112 to provide HDTV broadcasting, VOD services, and Internet access services to subscribers of a home network. The HDTV broadcast encoding apparatus 108 receives an analog broadcast signal such as a CATV (cable television) broadcast, MPEG encodes it, converts it into a standard definition television (METVG) moving picture expert group (MEPG) transport stream (TSP), and terrestrial HDTV broadcast. It receives the signal or cable HDTV broadcasting signal and converts it into HDTV class MPEG TS.

The VOD server 110 stores HDTV-level VOD content and outputs MPEG TS of content according to the VOD service request of the set-top box 130. RAS 112, commonly referred to as " remote access server ", performs IP address assignment and authentication services for connecting the set top box 130 to the Internet 106 in accordance with the Internet access request of the set top box 130.

The access network 102 is located between the service providing system 100 and the set top box 130, and is connected to the service providing system 100 by an optical line and connected to the set top box 130 by the VDSL 120. They receive the HDTV broadcast and VOD content through the VDSL 120 and provides a communication path between the service providing system 100 and the set-top box 130 to access the Internet.

The access network 102 is an example of using an Asynchronous Transfer Mode-Passive Optical Network (ATM-PON), which includes an ATM switch 114 and a plurality of optical line terminals (OLTs) 116 which are optical subscriber devices. An ONU (Optical Network Unit) 118 is provided. The ONUs 118 are connected to the OLT 116 by optical lines and the set-top box 130 by VDSL 120 to provide an interface between the optical lines and the VDSL 120. The OLTs 116 are optically connected to the ATM switch 114 and the ONUs 118 and multiplex upstream signals transmitted from the set top box 130 to the service providing system 100 via the ONUs 118. The downlink signals transmitted from the service providing system 100 to the set top box 130 are demultiplexed and transmitted through the ONUs 118. The ATM switch 114 is optically connected to the HDTV broadcasting encoding apparatus 108, the VOD server 110, the RAS 112, and the OLT 116 of the service providing system 100, and the MPEG of HDTV broadcasting or VOD content is connected. The TS is transmitted to the set-top box 130 through the OLT 116 and provides communication between the corresponding set-top box 130 and the RAS 112 according to the Internet access of the set-top box 130.

In addition, according to the present invention, when the access network requests two or more broadcasts in one set-top box, the access network re-encodes a plurality of single program transport streams (SPTSs) from the service providing system 100 to perform MPTS. Create Accordingly, the broadcast received through one network line in the set top box 130 has a form of MPTS. That is, the present invention re-encodes a corresponding single program transport stream (SPTS) at a system level for a plurality of required channels, generates an MPTS, and transmits the MPTS to the set-top box 130.

The subscriber's house 104 is provided with a client set-top box 130 and a TV 140-144 connected to the set-top box 130. The set-top box 130 in the subscriber's home 104 corresponds to any one of the subscribers of the home network, is connected to the access network 102 through the VDSL 120, and provides service through the access network 102. It is connected to the center 100, provides subscribers with Internet access through VDSL, and receives HDTV broadcasts or VOD contents through the VDSL 120 and provides them to the TVs 140-144 installed in the subscriber's home 104. . According to the present invention, when the set-top box 130 receives the Multi Program Transport Stream (MPTS) from the access network 102, one or more TVs 140-144 request each TV by demultiplexing the SPTS from the MPTS. Provides a transport stream (TS). In accordance with the present invention, the set-top box 130 multiplexes one or more program request signals requested by the connected TVs 140-144 according to the present invention and transmits them to the access network 102. The TV 36 may be an HDTV capable of receiving HDTV-class multimedia services such as HDTV broadcasting or HDTV-level VOD content.

The ONUs 118 are spaced apart from the subscriber's home 104 when the subscriber's home 104 is a general home, but is located in the subscriber's home 104 in the case of a hospital, a hotel, a company, a broadcaster, and the like. In addition, the OLTs 116 and ONUs 118 are connected to each other, for example, up to several kilometers apart with a 2.5 Gbps optical line, and the ONUs 118 and the set-top box 130 are for example 36 Mbps down, 3.6 upward, etc. It is connected as a VDSL 120 of Mbps spaced up to 300m apart.

3 is a diagram illustrating a protocol stack structure of an integrated home network system according to an embodiment of the present invention, and illustrates a protocol stack for exchanging data between a service providing system 100 and a set-top box 130. will be. Here, reference numeral 202 denotes a protocol stack inside the HDTV broadcasting encoding apparatus 108, reference numeral 204 denotes a protocol stack inside the VOD server 110, and reference numeral 206 denotes a protocol stack inside the ATM switch 114. Reference numeral 208 shows a protocol stack inside the ONU 118 and reference numeral 210 shows a protocol stack inside the set-top box 210.

As shown in FIG. 3, the TS from the VOD server 202 or the HDTV broadcast encoding device 204 is provided to the ONU 208 via the ATM switch 206, which provides the ATM stack up to the ONU 208. Is sent through. The ONU 208 delivers the TS through the VDSL stack to the VDSL stack of the set top box 210. When the set top box 210 receives the TS through the VDSL stack, the set top box 210 transmits the TS to a higher layer.

4 is a diagram illustrating a control request and a response made on a CCP between a server and a client according to an embodiment of the present invention. In FIG. 4, the server refers to a network level at which the set-top box 130 as a client requests broadcasting (program).

Referring to FIG. 4, the set-top box 130, which is a client, initially transmits a client ID message including its ID to the server through a control channel. Accordingly, after performing the authentication operation for the server, the server transmits a service guide message in service to the set-top box 130 through the control channel. When the user of the set-top box 130 selects a desired program, the set-top box 130 transmits information on the selected program, that is, a program selection message to the server through a control channel. When the server receives the program selection message, the server transmits a response message to the program selection to the corresponding set-top box 130 through the control channel. Thereafter, the server delivers a plurality of HDTV-level multimedia service programs, that is, a plurality of HDTV-class programs selected by the user, to the set-top box 130 through the video channel.

Specifically, the process of establishing a session between the client set-top box 130 and the server forms a new session through the session request through the SessionSetupRequest of the client and the Session SetupConfirm of the server. Table 1 shows the message format for this session setup.

According to the present invention, when transmission for one or more channels is requested, a new session is requested only when there is no session with the server. The message header is identical to the DSMCC standard. The clientId and serverId use authenticated serial numbers.

Meanwhile, the client set-top box 130 transmits a message for requesting a program to a server in order to select a channel from a plurality of connected TVs. Table 2 shows the message format for this program request.

As shown in Table 2, the client set-top box 130 requests a program through a ProgramSelect Request. The set-top box 130 as a client transmits a plurality of STBStatuss and broadcastProgramIds in columns in the order of NoOfPrograms and TV IDs instead of one BroadcastProgramId. The server responds to the multichannel request with a ProgramSelectConfirm, including a column of NoOfPrograms, a response, and a broadcastProgramId indicating the number of channels requested, such as a ProgramSelectRequest.

NoOfPrograms specifies the number of channels that the service supports on the client. The broadcastProgramId is composed of columns having the size of the number of TVs served by the client, and has the same order as that of the TV ID. Each represents a channel number of a broadcast requested by the corresponding TV, and the broadcastProgramId corresponding to the TV ID without the requested service is treated as '0'. The STBStatus field is used to classify the requested broadcast type (TV broadcast, VOD, etc.), and the broadcastProgramId specifies a channel number of the requested broadcast. The response specifies the error code, etc.

In summary, the program request signal consists of a DSMCC message header, a session ID field of 10 bytes, a "NoOfPrograms" field of 2 bytes that indicates the number of channels the client is supporting the service, and 2 each of which identifies the type of program requested. A "STBStatus" field composed of bytes, a "broadcastProgramId" field composed of four bytes each representing a channel number of a broadcast requested by the TV, and a client ID field.

On the other hand, ReleaseRequest requesting service termination can be requested from both server and client. Client sends ClientReleaseRequest to server only if all the TVs it is serving do not request service. If the service continues, keep the existing session. The server receiving the Client ReleaseRequest terminates the service by responding to the client with ClientReleaseConfirm (Fig. 6). When the server terminates the service, it sends a ServerReleaseRequest to the client to request the service to be terminated. The client responds with a ServerReleaseConfirm and terminates the broadcasting service for all TVs. Table 3 is a diagram illustrating a message format for release between a client and a server. The ReleaseRequest and ReleaseConfirm message formats required by the client and server are the same as shown in Table 3.

On the other hand, when the session is set up between the server and the set-top box 130, the server accepts and responds to the multimedia service request signal for one channel such as channel change or channel selection to the set-top box 130, the client Perform the function. However, there may occur a case where the network connection is abnormally terminated between the server or the service provider server (eg, an HDTV broadcasting apparatus, a VoD server, a web server, etc.) and the set-top box 130 which is a client. In this case, since the established session between the server or the service providing server and the client set-top box 130 is not normally terminated, the service providing server continuously provides the service to the client set-top box 130. In the present invention, in order to prevent such a waste of resources, the server periodically checks the status of the client set-top box 130 using the ServerStatusRequest. This message is sent to the set top box 130 once every predetermined time, for example, at 30 minute intervals. The transmission period of such a message can be changed depending on the system. If the client set-top box 130 does not send a response, the server resends the ServerStatusRequest to the client. If the client does not send a response to the ServerStatusRequest resent by the set-top box 130, the server sends a ReleaseRequest to the set-top box 130, the client to terminate the set session. Table 4 shows a message format for checking status between a client and a server. resourceNumber is a resource number (eg, mpeg) for which status is to be known, and resourceStatus is a field indicating a status of a resource and inputs a status such as whether an MPEG resource is used.

As described above, while the server and the client set-top box 130 exchange messages defined on the DAM-CC, the server performs an HDTV-class multimedia program selected by the user, that is, a corresponding SPTS at a system level for a plurality of channels required. The program transport stream is re-encoded to generate an MPTS and transmit the MPTS to the set-top box 130.

5 is a control flowchart when a session set request is received from a TV to which a client set-top box is connected according to an embodiment of the present invention, and FIG. 6 is a session release from a TV connected to a client set-top box according to an embodiment of the present invention. Control flow chart when receiving a request.

First, the session setup will be described with reference to FIG. 5. When the set-top box 130 receives a session setup request from one of a plurality of connected TVs 140-144, the set-top box 130 checks whether there is a TV currently in service in step 302. If there is no TV currently in service, the set-top box 130 proceeds to step 304 and transmits a session establishment request message to the server. The set top box 130 proceeds to step 306 to wait for a response to the session establishment request. If there is a response from the server to the session establishment request, the set-top box 130 proceeds to step 308 to establish a session with the server. Accordingly, any TV requesting session establishment can receive a desired service from a server.

On the other hand, with reference to Figure 6 with respect to the session release when the set-top box 130 receives a session release request from any of the plurality of TV (140-144) connected in step 312 checks whether there is a TV currently in service. . If there is no TV currently in service, the set-top box 130 proceeds to step 314 and transmits a session release request message to the server. The set top box 130 proceeds to step 316 to wait for a response to the session release request. If there is a response to the session release request from the server, the set-top box 130 proceeds to step 318 to release the session with the server.

As described above, in the present invention, a plurality of TVs connected to one set-top box may be simultaneously provided with a multimedia service without installing a set-top box on each TV to receive a multimedia service.

Claims (7)

In the multi-channel transmission and reception method in a home network, Multiplexing one or more program request signals from a plurality of TVs to the server in a session established between a server providing a multimedia service and a client connected to the plurality of TVs; The server re-encodes a single program transport stream (SPTS) corresponding to one or more channels in response to the one or more program request signals to generate a multi program transport stream (MPTS) and transmits the same to the client. Multi-channel transmission and reception method comprising the. The method of claim 1, further comprising: when the client receives the MPTS from the server, demultiplexing the SPTS from the received MPTS to provide a requested transport stream (TS) to the TV requesting the program. Multi-channel transmission and reception method characterized in that. The program request signal according to claim 1, wherein the program request signal includes a DSMCC message header, a session ID field composed of 10 bytes, a "NoOfPrograms" field composed of two bytes representing the number of channels supported by a client, and a type of a requested program. And a "broadcastProgramId" field consisting of 4 bytes each indicating a channel number of a broadcast requested by the TV, and a client ID field. The method of claim 3, wherein the " broadcastProgramId " field comprises columns having a size equal to the number of TVs serviced by a client. 4. The method of claim 3, wherein the server and the client establish a session directly through TCP / IP, thereby enabling session control and channel selection on one protocol stack. The method of claim 1, further comprising: when the client receives a session establishment request from any of the connected plurality of TVs, establishes a session with the server when there is no TV in service. Channel transmission and reception method. The method of claim 1, further comprising releasing the session with the server when there is no TV in service when the client receives a session release request from any of the connected plurality of TVs. Channel transmission and reception method.