KR0174943B1 - How to cancel session backup in DMC protocol - Google Patents

Abstract

The present invention relates to a method for canceling a client initiated session backup in DSM-CC protocol, comprising: authorizing a client session backup cancel request message from the client to the network; When a client session backup cancel request message is received from the client, forwarding a server session backup cancel command message to the server; In response to the server session backup cancellation instruction message transmitted from the network, if the server can cancel the session backup, cancel the session backup of the server, the server session backup cancellation response message indicating that the session backup of the server has been canceled Transmitting to the network; And upon receiving the server session backup cancellation response message from the network, canceling the session backup of the network and delivering a server session backup cancellation confirmation message to the client informing that the session backup of the network has been cancelled. do.

Description

How to cancel session backup in DSM-CC protocol

1 is a diagram illustrating a regular procedure for session initiation initiated by a client under a DSM-CC protocol.

2 is a block diagram of a sub, a network, and a client to which the present invention is applied.

3 is a flowchart illustrating a method for canceling session session in a DSM-CC protocol according to the present invention.

* Explanation of symbols for main parts of the drawings

100: client 102: network interface

104: MPEG2 transport 106: MPEG2 decoder

108: graphic control unit 110: system control unit

112: cancel command processor 114: memory

200: network 202: session controller

204: Cancel command processor 206: Resource control unit

300: server 302: storage unit

304: MPEG2 stream control unit 306: Application program control unit

308: Command control unit 310: Cancel command processor

The present invention relates to a command processing method between an interactive CATV and a server and a network, and in particular, a client-initiated session in a digital storage media command and control (hereinafter abbreviated as DSM-CC) protocol. Session cancellation method in the DSM-CC protocol for canceling a configuration.

Many digital storage media have different defined control commands. Thus, a user must know a set of differently defined digital storage media control commands in order to access MPEG bitstreams from other digital storage media.

The DSM-CC standard proposed by ISO to address these shortcomings is based on the ISO / IEC 11172 (MPEG-1) bitstream and ISO / IEC stored in the media, regardless of what digital storage media is used in the near or far-area. 13818 (MPEg-2) A set of protocols that define common operations and control functions for managing bitstreams.

On the other hand, to support a variety of applications such as video-on-demand (VOD), interactive video services, or video networks that respond instantly to demand in stand-alone and diverse network environments. Currently, DSM-CC has drafted an extension of the DSM-CC protocol (ISO / IEC 13818-6) in addition to the management of existing MPEG streams.

FIG. 1 is a diagram for explaining a regular procedure in which a command sequence proceeds when a client initiates session establishment under the prior art DSM-CC protocol.

In the first step, the client sends a Client Session SetUp Request message to the network to begin setting up a new session. The value of the session-ID field contains a client-ID and sessionNum unique to the client, and the value of the client-ID field is a unique identifier used to uniquely identify the client throughout the network. The value of the Server-ID field identifies the server that the client requests to establish a session. The field value of the user data counter (UserDataCount) is equal to the number of user data bytes displayed in the rest of the message.

In a second step, upon receiving the Client Request for Retrieval message, the network retrieves whether the Client-ID and Server-ID fields indicate the entities known to the network. If the value of this field is valid and the network can support a new session, the network sends a Server Session SetUp Indication message to the server identified by the Server-ID field. The value of the session-ID field is selected by the network and used to identify the session for the duration of the session, the value of the client-ID field being the same as the value received from the client. The values of the user data counter (userDataCount) and user data byte (userDataByte) fields are the same as the values for receiving the client session request message.

In the third step, the server checks the Client-ID field to ensure that it is a known client to the server as soon as it receives the server session instruction, and if the value of the Client-ID field is valid and the server can support a new session, Initiates a resource agreement for the session based on sending a server session response message to the network. The value of the Session-ID field is equal to the value of the Session-ID field of the Server Session Instruction Message from the network. The server uses the resource counter to initially set the number of resource types required to establish a session. For each resource type requested, the server includes a resource descriptor field in the ServerAddResourceRequest message. do.

In the fourth step, as soon as the network receives the server add support request message, it determines whether it is possible to repeatedly fulfill each individual resource request through the requested resource list. If the network can assign attached request values as the server is mandatory-negotiated for all resources, then the network is then forced-negotiated, non-enforced-negotiated, and non-enforced-non-enforced. It attempts to assign a value to those resources that are attached by agreement. Then create a server add support request message. This is the same value as the Support Counter field in the message, and for each resource requested, the network includes the Resource Descriptor field in the server add support-confirmation message.

In a fifth step, upon receiving a ServerAddResourceConfirm message having a response field encoded as a response OK, the network sends a ClientSessionSetUpConfirm message to the client. The value of the session-ID field is the same as the session-ID value received in the server support response. The value of the response field is response OK. The value of the resource counter field indicates the total number of resources initially allocated to the client side of the session. For each type of resource allocated, the network includes a resource resource descriptor field.

In the seventh step, as soon as the client receives the client session access confirmation message, it determines whether it is capable of using the resources allocated for the session by the network. If the client can use all allocated resources, the client determines if there is a user data byte passed to the server. If no user data byte is sent to the server, the session is considered active.

The related information of the command is briefly described as follows.

Client Session Backup Request: Session-ID, Client-ID, Server-ID, User Data Count, User Data Byte.

Server Session Instructions: Session-ID, Client-ID, Server-ID, User Data Count, User Data Byte.

Additional server resource requirements: session-ID, resourcecount, resource descriptor, user data count, user data byte.

Server Additional Resource Check: Session-ID, Response, ResourceCount, ResourceDescriptor, User Data Count, User Data Byte.

Server Session Backup Response: Session-ID, response, user data count, user data byte.

Client Session Check Up: Session-ID, Response, ResourceCount, ResourceDescriptor, User Data Count, User Data Byte.

Client Connection Request: Session-ID, User Data Count, User Data Byte.

Server Connection Instruction: Session-ID, User Data Count, User Data Byte.

As mentioned above, the interactive CATV is a series of command sequences for a session session command between the client, the network, and the server. Or more commands are sent and received between three subjects: client, network and server.

However, in some cases, the first request for a session backup command may require that the session backup command be changed due to a cancellation of the user or a change in the network environment before receiving the confirmation command. In this case, since there is no command for processing the DSM-CC protocol of the prior art, the exchange of a new command can be performed only after a series of command negotiations are completed. In more detail, once a session session command is initiated, the new session session cancel command must be provided again after receiving the confirmation command for the session session. As a result, the session back-up cancellation method of the conventional DSM-CC protocol has a disadvantage in that the utilization of time and resources is greatly reduced by repeatedly performing two command exchanges.

Accordingly, the present invention has been made to solve the above drawbacks, and an object of the present invention is to provide a method for canceling session backup in the DSM-CC protocol for canceling session initiated by a client. have.

According to the present invention for achieving the above object, a first step of authorizing a client session backup cancellation request message from the client to the network in order to cancel the session backup; When the client session backup cancellation request message is received from the client, transmitting a server session backup cancellation request message from the network to the server; A third step of determining whether the server can cancel the session backup in response to the server session backup cancel instruction message transmitted from the network; If the server cannot cancel the session backup, the server sends a first server session backup cancellation response message indicating that the session backup has not been canceled, and if the server can cancel the session backup, Canceling the session backup of the server and sending a second server session backup cancel response message to the network informing that the session backup of the server has been cancelled; When the first server session backup cancellation response message is received in the network, a first client session backup cancellation confirmation message is transmitted to the client indicating that the session backup of the server is not canceled. And upon receiving a server session backup cancel response message of the server, canceling the session backup of the network and delivering a second server session backup cancel confirmation message to the client informing that the session backup of the network has been cancelled. It features.

Hereinafter, the present invention will be described in detail with reference to the illustrated drawings.

2 is a block diagram schematically illustrating a configuration between a server, a network, and a client applied to cancel session sessions under the DSM-CC protocol according to the present invention.

The client 100 is composed of a network interface 102, an MPEG2 transport 104, an MPEG2 decoder 106, a graphics control unit 108, a system control unit 110, a cancellation command processor 112, and a memory 114. do.

The network interface 102 is connected to the network 200 and is responsible for an interface required for data transmission and reception between the client 100 side and the network 200.

The MPEG2 transport 104 performs a function of analyzing information bits of data transmitted and received and converting them to meet the MPEG2 standard.

The MPEG2 decoder 106 decodes data input from the MPEG2 transport 104 and provides the decoded data to the graphic control unit 108.

The graphic controller 108 performs graphics processing on the data decoded by the MPEG2 decoder 106 and outputs the same to the display apparatus.

The system control unit 110 controls the system initialization and the switching operation to the driving state and the overall operation of the system that occur during power-up or reboot (Re-Booting).

The cancel command processor 112 controls the cancel command to be applied to the present invention, and the memory 114 is configured to store data decoded from the MPEG2 decoder unit 106 or store information and other data about the client.

The network 200 supports the program logic session control unit 202 for controlling the connection between the network interface 112 of the server and the network interface 301 of the client, the cancel command processor 204 and data information to be applied to the present invention. It consists of a resource control unit 206.

The server 300 standardizes and controls the data in the form of an MPEG2 bit stream when restoring the data stored in the storage unit 302 and the data stored in the storage unit 302. The MPEG2 stream control unit 304, the application program control unit 306 for supporting the program based on the recording of the application program of the server 300, the command related to the DSM-CC protocol, and the command control unit for executing the command 308, the cancel command processor 310 to be applied to the present invention and a network interface 312 for interfacing with the network 200.

The method for canceling session sessions of the present invention configured as described above will be described in detail with reference to FIG.

When the client 100 authorizes the client session backup cancellation request message to the system control unit 110, the system control unit 110 receives the relevant data for the client session backup cancellation request message accordingly from the cancellation command processor 112 to provide a network. Authorization is made to the network 200 via the interface 102 (step 401).

The network 200 transmits a client session backup cancellation request message, which is transmitted through the network interface 102 of the client 100, to the session controller 202. The session controller 202 determines whether the signal currently input by the command set by the cancel command processor 204 and the resource controller 206 is a client session backup cancel request message.

If it is determined in step 402 that it is a client session backup cancel request message, the process proceeds to step 403 where a server session backup cancel command message is sent from the resource controller 206 of the network 200 to the session controller 202 and the network interface ( 312) to server 300 (step 404).

Subsequently, in step 405, if the command control unit 308 of the server 300 determines that a server session backup cancel instruction message has been received from the network 200, the process proceeds to step 407 and the session setup in the server 300. It is determined by the command control unit 308 whether it is possible to cancel.

If it is determined in step 407 that cancellation of session backup of server 300 is not possible, proceed to step 408 to cancel the first server session backup indicating that the session backup of server 300 is not canceled. The response message is sent to the network 200.

However, in step 407, if it is possible to cancel the session backup of the server 300, the flow proceeds to step 409 to cancel the session backup of the server 300, and informs that the session backup is canceled in the server 300 The second server session backup cancel response message signal is transmitted to the session controller 202 of the network 200 through the network interface 312 of the server 300.

In the above-described steps 408 and 409, the division of the first or second server session backup cancellation response message, that is, the identification of whether the session backup of the server 300 has not been canceled or has been canceled is the message response field of the DSM-CC. Provided on board.

Next, in step 410, it is determined whether the first or second server session backup cancellation response message has been delivered to the network 200, and the first or second server session backup cancellation response message is forwarded to the network 200. If yes, go to Step 412.

In step 412, if the network 200 receives the first server session backup cancel response message from the server 300, it is determined that the session backup of the server 300 has not been canceled and proceeds to step 413. As a result, the client 100 transmits a first client session backup cancellation confirmation message to the client 100 informing that the session backup requested by the client 100 has not been cancelled.

However, in step 412, if the network 200 receives the second server session backup cancel response from the server 300, it determines that the tax wash of the server 300 has been canceled, and proceeds to step 414. Cancels the session backup of the network 200 and terminates by providing the client 100 with a second client session backup cancellation confirmation message informing that the session backup of the network 200 has been cancelled.

In the above-described steps 413 and 414, the classification of the first or second client session backup cancellation confirmation message, that is, the identification of whether the session backup of the network 200 has not been canceled or has been canceled is the message response field of the DSM-CC. Provided on board.

In addition, the above-described message related to canceling session session according to the present invention is configured using a user defined message scenario code (user defined message scenario code) assigned to the message scenario field (message scenario field) of the DSM-CC, the assigned message Code ID is shown in the following table.

As described above, the present invention does not have a command for canceling a session initiated by a client in the existing DSM-CC, thereby compensating a disadvantage of greatly reducing the time and resource utilization between the server, the network, and the client. There is.

Claims (1)

A method for canceling session backups transmitted from a client to a server via a network under a Digital Storage Media Command and Control (hereinafter abbreviated as DSM-CC) protocol, to cancel the session backup, Authorizing a client session backup cancellation request message from the client to the network; When the client session backup cancellation request message is received from the client, transmitting a server session backup cancellation request message from the network to the server; A third step of determining whether the server can cancel the session backup in response to the server session backup cancel instruction message transmitted from the network; If the server cannot cancel the session backup, the server sends a first server session backup cancellation response message indicating that the session backup has not been canceled, and if the server can cancel the session backup, Canceling the session backup of the server and sending a second server session backup cancel response message to the network informing that the session backup of the server has been cancelled; When the first server session backup cancellation response message is received in the network, a first client session backup cancellation confirmation message is transmitted to the client indicating that the session backup of the server is not canceled. And upon receiving a server session backup cancel response message of the server, canceling the session backup of the network and delivering a second server session backup cancel confirmation message to the client informing that the session backup of the network has been cancelled. Method for canceling session backup in the DSM-CC protocol.