KR19990031323A - Operation Method of Session and Resource Management Processor in On-demand Video System - Google Patents

Abstract

The present invention can provide a near-real-time service by operating the function of a session and resource management processor operating in a user-to-network environment with a pipeline technique in an on-demand video system operated by a DSM-CC protocol. Session and resource management processor operating method. To this end, the method operates the message decoder so that the decoded message for the received message is transmitted only when the status flag of the state machine is in the idle state and at the same time it is returned to the standby state for receiving a new message. If a predetermined message is applied, the status flag is set to busy status to perform the corresponding function. If a predetermined transmission message is generated, the transmission message is transmitted only when the status flag of the message encoder is idle. Operate the state machine to set the state flag to the idle state, set the state flag to busy state when the prescribed message is approved, perform echoing, and if the message is output, set its state flag to the idle state. This is done by operating a message encoder.

Description

Operation Method of Session and Resource Management Processor in On-demand Video System

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of operating a Session & Resource Manager (SRM) processor existing on a network side in a Video On Demand, and in particular, a DSM-CC ( Digital Storage Media Command and Control (hereinafter, referred to as DSM-CC) is a method for operating a session and resource management processor to process a message using a pipeline technique in an on-demand video system supporting a protocol.

On-demand video system is a well-known video provider that provides the video information required by a given client immediately at the time you want to see, information provider consisting of a large server with the ability to store and transmit information ), A network that enables the transmission of information between the client and the information provider and the client, which is a TV user using the actual information, is operated in conjunction.

DSM-CC is defined by ISO to operate the on-demand video system described above, and has a common operation and control function for managing bitstreams stored in media regardless of the digital storage media used in the near or far area. It is a set of protocols. As shown in FIG. 1, the DSM-CC protocol is a user operating as a path for directly transmitting and receiving data between a client (or a client user, hereinafter referred to as a client) and a server (or a server user, hereinafter referred to as a server). There is a user-to-network environment, which operates as a path for transmitting and receiving data between the network and the client or between the network and the server. do.

That is, as shown in FIG. 1, the UN environment is an environment function entity type resident in a client, a network, and a server. The UU environment is an environment function entity type only in a client and a server. In such UN environment and UU environment, a session setup (or session installation) in which a predetermined client or server requests a session setup (SessionSetUpRequest) and session set up confirmation information is transmitted from the network to the client or server and the corresponding session is activated. ) A session disconnect event that causes a release request (ReleaseRequest) from an event and a client or server, and an additional resource request (ServerAdd ResourceRequest) originated from the server to form a Motion Picture Expert Group (MPEG) channel between the client and the server. Resource allocation events, in which the confirmation information is transmitted from the network to the corresponding server, are generated in the above-described UN environment, and the channel is formed before the session is activated and the additional resource request is generated. After that, the actual MPEG data The transfer is done in the UU environment.

On-demand video system operating in UU environment and UN environment has a problem that it is difficult to support multi-user environment because SRM operating in UN environment is configured to be processed by session unit which is basic service.

In order to solve this problem, a method of storing a current progress for each session and allowing access to a new session or another session when there is an idle state between transactions has been proposed. However, this also supports a multi-user environment, but it is not able to receive a new message until the transaction for the message originating from the user is completed, which has some limitations in providing a real-time service. .

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and in the video-on-demand system operated by the DSM-CC protocol, the function of a session and resource management processor operating in a user-to-network environment is a pipeline technique. Its purpose is to provide a session and resource management processor operating method that can provide services in close proximity to real time.

In order to achieve the above objects, a method of operating a session and a resource management processor according to the present invention is configured to include a message decoder, a state machine and a message encoder, so that at least one is connected through an asynchronous network (ATM) in a user-to-network environment. In an on-demand video system having a session and resource management device for accommodating at least one server UN processor and at least one client UN processor, a predetermined message is received from either the server UN processor or the client UN processor via an asynchronous communication network. The message decoder checks whether the message is valid by analyzing a header of the received message; Performing decoding on the received message if the received message is valid as a result of performing the first check step; A second checking step of checking whether a state flag for the state machine is busy after decoding; If the state flag of the state machine is busy, as a result of performing the second check step, a first transmission hold step of suspending transmission of the decoded message until the state flag of the state machine is set to an idle state; When the state flag of the state machine is in the idle state, transmitting the decoded message and returning to the state where the message decoder can receive a new message; When a predetermined message is transmitted from the message decoder, setting a state flag of the state machine to an idle state and performing a function of the state machine corresponding to the transmitted message; A third checking step of checking a state flag of a message encoder when a predetermined transmission message is generated as a result of the execution; A second transmission-holding step of suspending transmission of the outgoing message until the status flag of the message encoder is switched to the idle state as a result of performing the third check step; When the state flag of the message encoder is idle as a result of performing the third check step, transmitting a transmission message to the message encoder and setting the state flag of the state machine to the idle state; If the outgoing message is transmitted, setting a status flag of the message encoder to the busy state and performing encoding on the outgoing message; As a result of the encoding, when the encoded message is output, the step of setting the state flag of the message encoder to the idle state is performed.

1 is a conceptual diagram of an on-demand video system operated by the DSM-CC protocol;

2 is a block diagram of an on-demand video system in a user-to-network environment for performing a method according to the present invention;

3 is a flowchart illustrating a session and a resource management method according to the present invention.

<Description of Symbols for Main Parts of Drawings>

200: server UN (user to network) processor 210: client UN processor

220: ATM switch 230: session and resource management processor

231: ATM network card 232: Session operator

233: resource manager 2321: message decoder

2322: State Machine 2324: Message Encoder

2324: session information saver

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

FIG. 2 is a block diagram of an on-demand video system in a user-to-network (weakly referred to as UN) environment for carrying out the method according to the present invention, wherein the server UN processor 200, which resides on the server side, resides on the client side. The session and resource management (Session & Resource Manager, hereinafter referred to as SRM), which exists on the network side of the client UN processor 210 and which is present on the network side, creates a session between the client UN processor 210 and the server UN processor 200, and allocates and releases resources. Weak)) to the processor 230 and the ATM network to the server UN processor 200 and the SRM processor 230 and the client UN processor 210 and the ATM switch 220 to connect the data communication between the SRM processor 230 is performed. It is composed.

In particular, the SRM processor 230 is an ATM network card 231 that interfaces with the ATM switch 220 to allow data transmission and reception, and a session manager (Session Manager) for controlling the overall functions of the SRM processor 230 ( 232, the resource manager 233 is controlled by the session manager 232 and transmits the information to the ATM network card 231 so that resource allocation and release processing is performed. The session operating unit 232 includes a message decoder 2321, a state machine 2322, a message encoder 2323, and a session information storage 2324 for storing information for each session.

3 is an operational flow diagram for the method according to the invention.

Next, the operation of the flowchart shown in FIG. 3 will be described in detail with reference to FIG. 2.

First, when a message is received in step 301, the process proceeds to step 302, and the message decoder 2321 in the session manager 232 analyzes the header of the received message. As a result of the analysis, it is checked whether ProtocolDiscriminator information is transmitted as valid data. Protocol Discriminator information indicates whether the message is a DSM-CC message. As a result of the check, if it is determined that the ProtocolDiscriminator information is not valid data, the process proceeds to step 304 through step 303 to perform error generation processing and returns to step 301.

However, if it is determined that the ProtocolDiscriminator information is valid data, the process proceeds to step 305 through step 303. In step 305, the message decoder 2321 checks whether the dsmccType information is transmitted as valid data according to the result of analyzing the message header. Here, the dsmccType information is determined to be valid when indicating that the currently authorized message is used in the UN environment.

If the dsmccType information is invalid as a result of the check, the flow proceeds to step 303 to perform error generation processing as described above. However, if the check result of step 305 is valid, if the dsmccType information is valid, it proceeds to step 306 to determine whether the currently received message is sent from the client UN processor 210 according to the result of analyzing the message identifier (messageId). Check whether the message is sent from 200).

As a result of the check, if the received message is a message sent from the client UN processor 210, the process proceeds to step 308 through step 306. However, if the received message is a message sent from the server UN processor 200, the process proceeds from step 306 to step 308 via step 307. At this time, if the received message is not a message sent from any of the client UN processor 210 or the server UN processor 200, the process proceeds to step 304 to perform an error generation process.

In step 308, the message decoder 2321 performs decoding on the received message. In step 309, it is checked whether the state flag (hereinafter, referred to as StateM_busy) for the state machine 2322 is set to one. Here, StateM_busy indicates whether the current state machine 2232 is executing an arbitrary function. In this example, when StateM_busy is set to 1, the state machine 2232 is performing an arbitrary function, and StateM_busy is 0. If set, the state machine 2232 is not performing any function.

Accordingly, as a result of checking in step 309, when StateM_busy is 1, transmission of the decoded message is suspended while the state of StateM_busy is continuously checked. However, if the state M_busy is 0 as a result of the check in step 309, the process proceeds to step 310 and transfers the decoded information to the state machine 2322 and the operation of the message decoder 2321 returns to step 301. And the new message can be received.

On the other hand, when the message is transmitted from the message decoder 2321, the state machine 2322 sets StateM_busy to 1 in step 311, and proceeds to step 312 with reference to session information corresponding to the currently authorized message. It is operated as in the conventional way. At this time, the session information to be referred to is stored in the session information store 2324. The session information store 2324 has information such as the current progress status of each session and which session is present between which server and which client. The recorded session information is updated each time a transmission message is output from the state machine 2322.

When a predetermined transmission message is generated from the state machine 2232 according to the operation of the state machine 2322 in step 312, the flow proceeds to step 314 through step 313 to describe the status flag for the message encoder 2323 (hereinafter referred to as Encoding_busy). Check status).

Encoding_busy also indicates whether the message encoder 2323 is currently performing an encoding operation as in the above-described StateM_busy, and when Encoding_busy is set to 1, the message encoder 2323 is currently performing an encoding operation. If Encoding_busy is set to 0, the message encoder 2323 is not currently performing an encoding operation.

Therefore, when the result of the check in step 314 is Encoding_busy of 1, the check in step 314 is continued while the transmission of the outgoing message is suspended. However, as a result of checking in step 314, if Encoding_busy is 0, the process proceeds to step 315 and transmits the generated outgoing message to the message encoder 2323, and sets the StateM_busy to 0 and returns to step 310 to be transmitted. Maintain a wait for.

If a predetermined message is applied in step 315, the message encoder 2323 sets Encoding_busy to 1 in step 316, and proceeds to step 317 to perform encoding on the authorized message. When the encoding is completed and the corresponding message is output, the process proceeds to step 319 through step 318 to set the Encoding_busy flag to 0, and proceeds to step 315 to wait for encoding for a message to be transmitted from the state machine 2232. Will be maintained.

As described above, the present invention provides a message decoding process, a state machine performing process, and a message encoding process performed in a session and resource management processor operating in a user-to-network environment in an on-demand video system operated by a DSM-CC protocol. By operating by pipeline method, it is possible not only to support the environment for multi-users but also to process 3 messages at the same time, thereby increasing the message processing capability of the session and resource management processor to provide near real-time service for multi-users. It can work.

Claims (1)

Session and resource management configured to include at least one server UN processor and at least one client UN processor over an asynchronous network (ATM) in a user-to-network environment, configured to include a message decoder, a state machine, and a message encoder In an on-demand video system with a device, When a predetermined message is received from either the server UN processor or the client UN processor through the asynchronous communication network, the message decoder analyzes a header of the received message and checks whether the message is valid; If the received message is valid as a result of performing the first check step, decoding the received message; A second checking step of checking whether a state flag for the state machine is busy after performing the decoding; A first transmission hold step of suspending transmission of the decoded message until the state flag of the state machine is set to an idle state as a result of performing the second check step; When the state flag of the state machine is in the idle state, transmitting the decoded message and returning to the state where the message decoder can receive a new message; When a predetermined message is transmitted from the message decoder, setting a state flag of the state machine to an idle state and performing a function of the state machine corresponding to the transmitted message; A third checking step of checking a state flag of the message encoder when a predetermined transmission message is generated as a result of the execution; A second transmission-holding step of suspending transmission of the outgoing message until the status flag of the message encoder is switched to an idle state as a result of performing the third check step; When the state flag of the message encoder is idle as a result of performing the third check step, transmitting a transmission message to the message encoder and setting the state flag of the state machine to the idle state; When the transmission message is transmitted, setting a status flag of the message encoder to a busy state and performing encoding on the transmission message; And when the encoded message is output as a result of the encoding, setting the state flag of the message encoder to an idle state.