KR20000021865A - Method for adjusting server node of video on demand - Google Patents

Abstract

PURPOSE: A method for adjusting server node of video on demand is provided to perform a client service request by performing a node adjustment to a VOD server. CONSTITUTION: A session managing unit informs a receipt of a client service request message to a node adjustment server node adjusting unit when the client service request message is received through a network managing unit(600). The node adjustment server node adjusting unit searches a download of a node adjustment server from information stored in a node adjustment server information storing unit(610). The node adjustment server node adjusting unit informs that a service is requested from a client to the node adjustment server(620). A corresponding node adjustment server detects a VOD address for performing a client service request among connected VOD servers(630). The corresponding node adjustment server provides the VOD server address to an SRM and the SRM provides the provided VOD server address to a corresponding client(640).

Description

How to Load-Load Video Server Loads

The present invention relates to video on demand, and in particular, to perform load control in a distributed VOD server using a DSM-CC (Digital Storage Media Command and Control, hereinafter abbreviated as DSM-CC) UN protocol. Server load control method in an on-demand video system.

Due to the rapid development of the high-speed information and communication infrastructure, due to the rapid development of the semiconductor and information and communication industries, the user's desire to obtain information in an interactive and active way, rather than simply receiving the information passively, is satisfied. One way to do this is to accelerate the development of interactive cable television (I-CATV), that is, the use of digital interactive cable television service technology instead of analogue information (e.g. video information, etc.) for television viewers. Video-on-demand (VOD) services are available that allow you to get them right when you want. In order to realize such an on-demand video service, an information provider composed of a large-capacity server capable of storing and transmitting information, a client who is a television user using real information, and a transmission of information between the information provider and the client A network that enables this is operated in conjunction with.

On the other hand, DSM-CC is defined by ISO for the standardization of the on-demand video system described above. The DSM-CC is a common operation for managing bitstreams stored in media regardless of what digital storage media are used in a near or far region. A set of protocols defining control functions. The DSM-CC protocol is a user-to-user (UU) which directly transmits and receives data between a client (or client user, hereinafter referred to as a client) and a server (or server user, hereinafter referred to as a server). Environment and a user-to-network (weakly called UN) environment where data is transmitted and received between the network and the client or between the network and the server.

In the UU environment and the UN environment, when a predetermined client or server requests a session set up request to the network side, the network side transmits session set up confirmation information to the corresponding client or server to perform a step of activating the corresponding session. Then, the release request (ReleaseRequest) is generated from the client or server, the session is released, and the confidence information according to the resource request generated from the server to form a Motion Picture Expert Group (MPEG) channel between the client and the server is generated from the network. The transmission to the server is performed in the UN environment, before the session is activated and the above-mentioned address resource request is generated, and after the channel formation for the address resource request, the actual MPEG data is transmitted in the UU environment.

As described above, in an on-demand video system operating in a UU environment and a UN environment, a VOD server needs a high performance VOD server system having a large amount of information. Such a high performance VOD server system requires a high cost as a single VOD server system, and requires a VOD server system having the same information providing capability as a single expensive VOD server system by distributing a low cost VOD server system. FIG. 1 is a block diagram illustrating a load balancing device of a distributed VOD server in which a low-cost VOD server is multi-configured in place of the expensive single VOD server system, and performs a service request of a client among a plurality of VOD servers. It is configured to make a connection to that VOD server. That is, if there is a service request from a predetermined client among the plurality of clients 130, the session and resource manager (hereinafter referred to as SRM) 120 may load a message about the service request of the client. In addition, the load control server 110 detects the load state of the multi-VOD server 100 when the client service request message is provided from the SRM 120 to perform a service request of the client by performing a connection to the corresponding VOD server do.

However, the load regulation apparatus of the distributed VOD server system is a configuration in which a single load regulation server 110 is connected to a multi-VOD server 100 configured as a group, as shown in the figure, and the load regulation server 110. ) Is down due to a system failure or some other factor, the VOD servers connected to a single load control server 110 is not available, so that a client's service request cannot be performed. .

The present invention has been made to solve the above problems, the object of the present invention is that even if the load control server to perform the connection to the corresponding VOD server according to the client service request in the distributed VOD server structure of the on-demand video system The purpose is to provide an on-demand video server load balancing method for performing client service requests by performing load balancing to connect to the VOD server.

The present invention for achieving the above object,

The DSM-CC protocol is used in an on-demand video system composed of SRM that connects to a VOD server capable of performing a client service request to VOD servers that are configured and connected to the first to K th load balancing servers. 1. A method of performing load balancing, the method comprising: a first step of determining whether a service request message is received from the client; A second step of searching for a down load control server among the first to K th load control servers when the client service request message is received; A third step of providing the client service request message to a load control server that is not down among the first to K-th load control servers as a result of the search of the second step; A fourth step of detecting a VOD server address among the VOD servers having the capability of performing the client service request, after receiving the client service request message by the third step; And a fifth step of notifying the client of the VOD server address detected in the fourth step.

1 is a block diagram showing the configuration of a load balancing device of a distributed structure of a conventional VOD server,

2 is a block diagram showing the configuration of a load balancing device of a distributed structure of a VOD server according to the present invention,

3 is a detailed block diagram of the SRM shown in FIG.

4 is a detailed block diagram of the load control server shown in FIG.

5 is a load adjustment data table according to an embodiment of the present invention,

6 is a flowchart for performing a video server load adjustment method on demand according to the present invention.

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

100: VOD server 110, 200: load balancing server

120: SRM 130: Client

300, 400: switch

Hereinafter, with reference to the accompanying drawings will be described in detail the operation of the preferred embodiment according to the present invention.

2 is a block diagram showing the configuration of a load balancing device in a distributed structure of a VOD server according to the present invention. When a service request is received from a predetermined client among the first to N-th clients 130, the SRM 120 determines a first request. When the K-th load balancing server 200 provides the client service request message to the load balancing server to which the VOD server capable of providing the information according to the client service request is connected, the load balancing server is connected to the first to (KN) The VOD server searches for a corresponding VOD server, receives information according to a client service request, provides the information to the SRM 120, and the SRM 120 provides information to a predetermined client.

3, when a message for a service request is received from a predetermined client, the corresponding load control server is searched among a plurality of load control servers to provide a message for the service request, and information is provided to the client by receiving information from the load control server. As a block diagram showing the configuration of the SRM 120, the network management unit 121, the default information storage unit 122, the session management unit 123, the load control server load control unit 124, the resource management unit 125 and the load The control server information storage unit 126 is configured, and FIG. 4 receives a message for a service request from the SRM 120 and searches for a VOD server that can provide information according to a client service request among the connected multi VOD servers. And a block diagram showing a configuration of the load control server 200 receiving information from the VOD server and providing the information to the SRM 120. The default information storage unit 210 and the network are shown in FIG. It consists of the management unit 220, a message intermediary part (230), VOD server load control unit (240), VOD server information storage unit 250.

At this time, in the reference numeral setting of Figs. 3 and 4, the components shown in Fig. 1 were designated by the same reference numerals.

A detailed operation description of the SRM 120 is as follows.

When the network management unit 121 correctly requests a message about a service request, that is, a UN Config message, from a predetermined client among the first to Nth clients through the switch 300, the network manager 121 processes the information and provides it to the session management unit 123. The information provided from the load control server among the first to K th load control servers is provided to the predetermined client through the switch 300.

The session manager 123 establishes a session so that a predetermined client among the first to N-th clients can receive a service from the corresponding server among the first to K-th load control servers, and releases the session when the service is finished. That is, the session manager 123 establishes a session by the resources allocated by the resource manager 125 so that the message is provided from the VOD server when a message according to a predetermined client service request is provided from the network manager 121. After the service is provided from the corresponding VOD server, the resource manager 125 releases the allocated resources, and the session manager 123 releases the formed session, and then, with the UN Config confirmation message as described below, the default ( default) provides default server address ID information provided by the server information storage 122.

The load control server information storage unit 126 stores data for searching for a load control server connected to a VOD server capable of performing a client service request among the first to K-th load control servers 200. . That is, the load regulation server information storage unit 126 may pump the addresses of the first to K th load regulation servers, the addresses of the VOD servers connected to the first to the K th load regulation servers, and the maximum at each of the VOD servers. The amount of video streams present (M _B : the information provided by the VOD server is in the form of MPEG bit streams compressed and coded at a predetermined bit rate, which refers to the maximum bit rate that can be pumped per second), and the amount of pumped video streams in each VOD server ( U _B ) information and down state information of the first to K th load control servers are stored to provide them when the load control server load adjuster 124 is requested.

At this time, the load control server load control unit 124 requests the above information to the load control server information storage unit 126 when a predetermined client service request message is provided from the session manager 123 to load the first to K th loads. After searching the load control server among the adjustment servers, the load control server address information is provided to the default server information storage 122.

In addition, the session manager 123 releases the session as described above, provides a UN Config confirmation message, receives default server address ID information from the default server information storage 122, and receives the first through thru switch 300. Provided to any one of the Nth clients. Thus, a UU environment is formed that can directly transmit and receive data between a given client and a given VOD server.

On the other hand, the operation in the first to K th load adjustment server is performed as follows. That is, when a client service request message is provided from the SRM 120 to a predetermined load control server among the first to Kth load control servers, that is, the load control server that is not down, the network management unit 220 processes the VOD server load by processing it. Provided to the unit 240. At this time, the VOD server load control unit 240 to the VOD server information storage unit 250 to search for the corresponding VOD servers that can provide information according to the client service request among the VOD servers connected in a group Requires VOD server information.

The VOD server information storage unit 250 includes address information of VOD servers that are grouped and connected to a corresponding load control server, and a maximum amount of video streams M _B that can be pumped in each of the VOD servers, and a VOD server. the information (U _B) for the pumping amount in the video stream is stored. Accordingly, the VOD server load controller 240 detects the VOD server address information based on the information provided from the VOD server information storage unit 250 and provides the VOD server address information to the network manager 220, and the network manager 220 provides the VOD server. After providing and storing the VOD server address information provided from the load adjusting unit 240 to the default server information storage unit 210, the VOD server address information is provided to the SRM 120 along with the configuration confirmation information.

In addition, the message broker 230 connected to the network manager 220 performs a role of mediating a message with the corresponding VOD servers.

5 is a diagram illustrating a load regulation data table according to a preferred embodiment of the present invention, and FIGS. 6A and 6B are flowcharts of a method for performing load regulation in a distributed VOD server according to the present invention. It will be described in detail with reference to.

As shown in FIG. 5, the load adjusting server load adjusting unit 124 of the SRM 120 may pump the load adjusting server address information, the VOD server address information, the maximum bandwidth of the VOD server, that is, the maximum of the VOD server. The video stream amount M _B and the pumped video stream amount U _B information from the VOD server and down state information of the first to K th load regulation servers are stored, respectively. Contains the address information of each VOD server that is connected in a group, and the maximum bandwidth of the VOD server, that is, the maximum amount of video stream (M _B ) that can be pumped in the VOD server, and the pumped video stream in the VOD server. Quantity (U _B ) information is stored.

Therefore, when the client service request message is received through the network manager 121 (S600), the session manager 123 of the SRM 124 notifies the load control server load adjuster 124 that the client service request message has been received. Load control server The load control unit 124 retrieves whether the load control server is down from the information stored in the load control server information storage unit 126, that is, down state information of the table information shown in FIG. . As a result of the search, the load balancing server (valid state) except the down load balancing server (Invalid state) is informed that the service is requested from the client to the load balancing server having an address of 135.135.134.1 (step 620).

At this time, the load control server, that is, the load control server having an address of 135.135.134.1, detects a VOD server address capable of performing a client service request among the VOD servers configured and connected in a group (step 630). That is, as shown in FIG. 6B, the VOD server load adjuster 240 of the load control server selects the first VOD server address among the plurality of VOD servers based on the information stored in the VOD server information storage 250. Detection (step 631) determines the information providing capability of the address. That is, if the information amount obtained by subtracting the maximum pumpable video stream amount M _B from the first VOD server address from the video stream amount U _B already pumped by the first VOD server is greater than the information amount according to the client service request, In operation 635, the first VOD server address information is provided to the SRM 120. For example, when the amount of video stream M _B that can be pumped by the invitation at the first VOD server address is 100 Mbps and the amount of video stream U _{B that} is already pumped by the first VOD server is 60 Mbps, the first VOD Since the video stream pumping amount that can be provided by the server address is 40 Mbps, the first VOD server address is designated only when the bit stream pumping amount corresponding to the performance of the client service request corresponds to 40 Mbps. In operation 632, the amount of information obtained by subtracting the pumped video stream amount U _B from the first VOD server from the video stream amount M _B that can be pumped to the maximum of the first VOD server address is the information amount according to the client service request. If not greater than or equal to the next VOD server, for example, if the second VOD server is detected (step 633) and detected, repeat the above process, that is, step 632, and if the next VOD server is not detected, an error code is generated ( Step 634).

On the other hand, the load control server detects the VOD server address having the ability to perform the client service request by the process in step 630 as described above, and provides the VOD server address to the SRM 120, SRM 120, Operation 120 is provided to the client (step 640).

As described above, the present invention provides a predetermined method by performing load balancing to a VOD server capable of performing a client service request for VOD servers configured and connected to groups of the first to K-th load balancing servers, respectively. Even if the load balancing server is down, there is an effect that the client service request can be performed.

Claims (2)

On-demand video system consisting of a session and resource manager (SRM) for connecting to the VOD server capable of performing client service requests to the VOD servers that are configured and connected to the first to K th load balancing servers, respectively. In the method of performing load balancing using the DSM-CC protocol in the A first step of determining whether a service request message is received from the client; A second step of searching for a down load control server among the first to K th load control servers when the client service request message is received; A third step of providing the client service request message to the load balancing server that is not down among the first to K th load balancing servers as a result of the search of the second step; A fourth step of detecting a VOD server address among the VOD servers having the capability of performing the client service request, after receiving the client service request message by the third step; And a fifth step of notifying the client of the VOD server address detected in the fourth step. The method of claim 1, wherein the fourth step comprises: the video stream amount U already pumped from the maximum amount of video stream M _B that can be pumped among the VOD server addresses that are grouped and connected to the load control server. _And detecting a VOD server address capable of performing the service request of the client by subtracting _B ) the video stream amount.