JPH08228334A - Near video on-demand system in atm network - Google Patents

Abstract

PURPOSE: To provide a near VOD(video on demand) system provided with many functions which supplies the image information and audio information of a server to a subscriber terminal via an ATM(asynchronous transfer mode) switching network. CONSTITUTION: This system is provided with a server housing ATM node 4 which houses the server 5 equipped with a memory device 5b in which service information is stored, a subscriber housing ATM node 2 which houses a subscriber, and the subscriber terminals 1a, 1b, and the node 4 is connected to the node 2 via an ATM network 3. When the server 5 receives a request of reception of the same service from another subscriber B until a time when the transmission of the service information requested by the subscriber A from the server 5 to the subscriber A is started, a communication processing function part 5c transmits a message of multi-point ATM path connection request for same service information to another subscriber B, and connects a multi-point ATM path before the transmission of the service information is started.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication system for providing service information such as image information and audio information to one or a plurality of subscribers on demand in a broadcast type, and uses an asynchronous transfer mode (ATM). Existing video-on-demand (VOD) system for distributing information over existing networks.

[0002]

2. Description of the Related Art ATM is now rapidly becoming widespread as a broadband communication technology capable of more economically and efficiently connecting various conventional communication services and centrally managing them. Various service providing systems using such ATM technology as a backbone network are being realized.

Conventionally, there are some examples of video information distribution services in which a server, which is an information storage device, is used as an information transmission source, and a dedicated terminal connected to a TV terminal is used as a receiver. A CATV service that connects the server and the receiver at the subscriber's home via a telephone line or a coaxial cable to build a system, and transmits image and audio information such as movies and the like stored in the server, and programs that the subscriber makes Video-on-demand (VOD) service that allows you to select and listen to a program you want to watch at any time by sending a viewing request to the server via a telephone line or coaxial cable There is a near-VOD service that distributes information to subscribers by broadcasting and allows the subscribers to watch a program selected by themselves at the start time of the program. Attempts have been made to accommodate the above services in the ATM network.

Of these, AT near-VOD service
When accommodating in the M network, it is necessary to allocate image information and audio information for each service corresponding to each subscriber, that is, to set up an ATM path. ATM in this case
The path is set by a PVC (Permanent Virtua) in which virtual channels are fixedly assigned in advance for each service.
l Circuit) Near-V in ATM network by connection method
OD / service was realized. When a virtual path is set by this PVC connection method, there is a problem that as a result, the bandwidth between the server and the ATM switch accommodating the server becomes insufficient as the number of subscribers increases. Therefore, in the trial, we dealt with the problem of bandwidth shortage by adding multiple servers.

Further, Japanese Patent Laid-Open No. 2-186791 discloses an ATM distribution switch of a node accommodating a subscriber in order to solve the problem of insufficient bandwidth between a server and an ATM exchange accommodating the server. A method is disclosed in which ATM cells are distributed to subscribers and a PVC connection is made between the server and the subscribers in a point-to-multipoint configuration to reduce the bandwidth between the server and the ATM network. However, in this system, in the near VOD system, the server always distributes ATM cells to the subscribers at regular intervals, and the subscribers receive A including the service information requested by themselves.
Since the TM cells are extracted, the hardware scale of the ATM distribution switch itself becomes large, and the ATM switch control becomes complicated as the number of subscribers increases. Therefore, there is a need for a method of setting the path between the server and the subscriber so that the amount of hardware of the switch is reduced and simpler control is possible.

[0006] In the near VOD service, the server transmits a cell of service information to each subscriber in a broadcast type at regular time intervals, and the subscriber includes an AT including information on a program desired to be selected.
Since the M cell is selected by the terminal, when the ATM cell is selected in the middle of a certain time interval, the ATM path between the terminal and the server is set in the middle of the program, and the selected channel program is started in the middle. There was the inconvenience of being projected.

[0007] In such a near VOD service, the service information transmitted from the server is converted into ATM cells and transmitted to the subscriber in a broadcast type, so that the channel selected by the subscriber is selected. Therefore, even if the same program is changed to a channel in a different time zone, it is judged that a different channel is selected and the fee is charged again. There was a problem of heavy billing.

[0008]

The present invention is a near-VO system.
D. A system with more functions that solves the above problems in the system and can provide the subscriber terminal with the image information and voice information of the server through the ATM switching network.
The purpose is to realize a VOD system.

[0009]

In order to achieve the above object, the near VOD system of the present invention comprises a server having a storage device for accumulating service information, a server accommodating ATM node accommodating the server, and a subscriber. A subscriber accommodating ATM node for accommodating a subscriber and a subscriber terminal, and other subscribers by the time when transmission of image information and voice information of a service requested by a subscriber is started from the server to the subscriber. When the server receives a request to receive the same service from another person, the communication processing function unit of the server sends the message of the multipoint ATM path connection request for the image information and the voice information of the same service to the subscriber. And other subscribers, and connect the multipoint ATM path before the start time of transmission of service image information and voice information. It has the means.

Further, the near VOD system of the present invention includes a server having a storage device for accumulating service information, a server accommodating node accommodating a server, a subscriber accommodating node accommodating a subscriber, and a subscriber terminal. The communication function processing unit of the server calculates the waiting time before the transmission of image information and audio information of the service requested by a subscriber from the server to the subscriber. , Start the switching process of the server between the communication processing function unit of the server and the communication processing function unit of another server, and use the idle time until the server starts transmitting image information and audio information to the terminal. The other server and the ATM path of the subscriber, and when the free time becomes short, the communication processing function unit of the server and the communication processing function unit of the other server are supported again. Start bar switching process, having means for providing image information and audio information of a service subscriber to connect a path between the server and the subscriber has requested.

Further, the near VOD system of the present invention includes a server having a storage device for accumulating service information, a server accommodating node accommodating the server, a subscriber accommodating node accommodating a subscriber, and a subscriber terminal. Which provides certain service information to the subscriber terminal through the ATM network at regular time intervals, and the subscriber terminal sends a request for setting an ATM path to the server to the ATM network to select a service Information to ATM with the server
When a plurality of subscriber terminals send a service request signal in the same time zone to the server, the communication processing function unit of the server sends the service request signal to each of the subscribers. The time is detected, and those times are stored in the time table of the communication processing function unit and compared with the start time of the requested service information, and the service request time from the plurality of subscribers starts the service information provision. After that, the communication processing function unit of the server sends a signal of multipoint ATM path connection to the subscribers who have searched for the request within the prescribed time after sending the service request within the prescribed time. And connecting the same path as the ATM path already connected at the service start time with the server.

[0012]

In the past, when image information and audio information of the same program were provided to a plurality of subscribers, an ATM connection was connected to each subscriber, so that the bandwidth required for the ATM connections corresponding to the number of subscribers. Was needed. By adopting the near VOD system of the present invention, when a program viewing request is transmitted from another subscriber to a program selected by the subscriber, an ATM with the server of these subscribers is transmitted. Since the path is set to have the point-to-multipoint ATM path connection configuration, the band required for the ATM connection can be reduced. Further, since the same ATM path is set from the subscriber exchange to the subscriber terminal, it is possible to provide the service to a plurality of subscribers who have requested the same service by the program start time, and at the same time, the server Can transmit the service information requested by the subscriber to the ATM cell only to the subscriber who is transmitting the request for viewing the program.

With such a configuration, the ATM distribution switch of the subscriber exchange only needs to distribute only the minimum required ATM cells to the subscriber terminals, which is effective in reducing the load on the switch. Furthermore, which subscriber sent the program viewing request to the server can be centrally managed by the communication processing function unit of the server, which can cause a failure on the transmission line or a temporary interruption of information provision to the subscriber terminal. Since it can be managed by the server, it also has the advantage that it is easy to deal with system maintenance and fault handling.

Further, on the side of the near VOD service provider, for example, if a movie of 2 hours is provided to the subscriber at 15-minute intervals, 8 channels are required. Therefore, the same movie software need not be prepared. However, if it is provided at intervals of 30 minutes, the amount of software will be four. However, as seen from the subscriber side, the channel spacing is 3
At 0 minutes, the waiting time will be considerably long. By applying the near VOD system of the present invention, the server automatically selects a channel that minimizes the waiting time even if the channel interval is 30 minutes. Can be reduced, and at the same time, a system can be constructed so that subscribers do not have to worry too much about waiting time.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual diagram showing a configuration example of a near video on demand (VOD) system according to the present invention.

In the near VOD system of this system, the ATM subscriber exchange 2 accommodating the subscriber terminals 1a and 1b is connected to the server accommodating ATM via the ATM exchange network 3.
It is connected to the exchange 4 and sends and receives ATM cells. The server accommodating ATM exchange 4 accommodates a server 5 which is a storage device for providing service information of near-VOD service. The server 5 receives a signal for ATM path connection transmitted from the subscribers 1a and 1b and a storage device 5b for accumulating image information and voice information as service information, and performs processing for ATM path connection and release. The communication function processing unit 5c, and A transmitted from the communication function processing unit 5c
Upon receiving a command such as TM path connection, which AT is assigned to which channel in the service information stored in the storage device 5b.
It is composed of a server main control unit 5a for instructing whether to set the M path.

FIG. 2 is a block diagram showing the internal functions of the communication function processing section 5c. The communication function processing unit 5c
The interface IF includes a call processing unit 51, a timer 52, a subscriber time table 53, an ATM connection table 54, and a channel information storage unit 55.
It is connected to the server main control unit 5a via. The call processing unit 51 transmits and receives a call control signal for ATM path connection transmitted from the subscriber. By this call control signal, a subscriber of the ATM network performs a signaling process necessary for connecting or releasing the ATM path between the subscriber and the server by the SVC method to transmit the layer 3 message to the ATM Forum.
Process according to UNI 3.0 protocol. The timer 52 is a timer for waiting for a message to be answered when the call processing unit 51 is activated, and the service information of the program from the time when the program transmission request signal is transmitted from the subscriber. It functions as a timer to count the time until the transmission to. The subscriber time table 53 stores which subscriber has transmitted the program viewing request to the server at what time. The ATM connection table 54 transmits / receives call control signals for ATM path connection to which VPI and VC to which subscriber.
This is a part for storing whether I is assigned. The channel information storage unit 55 stores which subscriber has accessed which channel.

Next, the operation of this embodiment when the subscriber issues a channel viewing request will be described. FIG. 3 shows a flow from the time when the subscriber A sends a program viewing request to the server until the ATM connection is set up between the server and the subscriber terminal 1a.

The subscriber A selects the channel of the program in the time zone he / she wants to watch (A). The subscriber terminal 1a is an AT for transmitting service information of the selected channel.
In order to set the M path with the server 5, a setup signal which is a call control signal for setting the ATM path is transmitted (B1). Upon receiving this signal, the ATM subscriber exchange (subscriber accommodating node) 2 also transmits a setup signal to the server accommodating ATM exchange (server accommodating node) 4 (B2). Upon receiving this signal, the server accommodating node 4 transmits a setup signal to the communication function processing unit 5c of the server to set the ATM path with the server (C). Upon receiving the setup signal, the communication function processing unit 5c activates the ATM path connection process and returns a response signal indicating that the process is in progress to the server accommodating node 4 (D).

Thereafter, the communication function processing section 5c stores the time when the subscriber transmits the program viewing request in the subscriber time table 53 and activates the timer 52. Then, the channel information storage unit 55 stores the channel requested by the subscriber and which subscriber transmitted the service request. The received setup signal is processed by the call processing unit 51 for ATM path setting and assigned to the subscriber.
I / VPI, bandwidth, quality of service (QoS), etc. are determined, and when this is completed, an ATM path setting signal is transmitted to the server main controller 5a (F). Subsequently, the communication processing control unit 5c returns a connect signal notifying that the ATM path connection processing is completed to the server accommodating node 4 (G). The server accommodating node 4 may return a confirmation signal for notifying that the connect signal has been certainly received to the communication processing control unit 5c (H). The server accommodating node 4 that has received the connect signal is the subscriber accommodating node 2
To the subscriber accommodation node 2 (I)
Transmits a connect signal for notifying the completion of the ATM path connection with the subscriber terminal 1 to the subscriber terminal 2 (J). At this point (300), A between the subscriber terminal 1a and the server 5
This means that the TM path (301) has been connected.

When the ATM path (301) is set up between the subscriber and the server, the information of the channel requested by the subscriber will be transmitted to the subscriber terminal 1a through this path. In the near VOD service of the present invention, the process of immediately transmitting information to the subscriber is not started. As described above, the timer 52 is started in the process 20, and the timer 52 is activated until the broadcast start time of the program requested by the subscriber is reached. In process 21, after the timer 52 expires, the communication function processing unit 5c of the server
Sends a request to send service information to the server main controller 5a (K). Server main control unit 5 that received this signal
The a sends a command to the subscriber to send the service information to the storage device 5b of the server (L). At this point, the server transmits the requested channel information to the subscriber through the ATM path 301 set in the above procedure for the first time (M). This system provides services to subscribers through the above procedure.

Next, the operation when a plurality of subscribers make a viewing request for the same program will be described. FIG. 4 shows a process when the subscriber terminals 1a and 1b send a viewing request of the same channel to the server. It is assumed that the ATM path has already been set up between the subscriber A and the server by the procedure shown in FIG. 3 (A). Further, if the subscriber terminal 1b transmits a viewing request of the same channel as the subscriber terminal 1a (B), the subscriber accommodating node 2 transmits an ATM path connection request setup signal to the server accommodating node 4 (C1). . Subsequently, the server accommodating node 4 transmits a setup signal to the communication processing function unit 5c of the server 5 (C2).

Upon receiving the setup signal, the communication processing function section 5a starts the ATM path connection processing 40. In the process 40, the operations of the timer 52 and the subscriber time table 53 in the communication function processing unit are the same as those shown in FIG. In the channel information storage unit 55, the channel to which the subscriber A has transmitted the viewing request has already been stored, and the channel requested by the subscriber terminal 1b and the channel requested by the subscriber terminal 1a are the same channel. Upon recognition, the call processing unit 51 is notified to that effect. Then, the call processing unit 51 determines that the ATM path connected to the subscriber terminal 1b needs to be set to the same path as that of the subscriber terminal 1a, and the ATM path connection for the point-to-multipoint configuration is established. The signal ADD PARTY is transmitted to the server accommodating node 4 (D). Upon receiving this signal, the server accommodating node 4 transmits to the subscriber accommodating node 2 a connect signal indicating the completion of the ATM path connection of the point-to-multipoint configuration (E). Upon receipt of this signal, the subscriber accommodation node 2 transmits a similar signal to the subscriber terminal 1b (F), and at this point (400), a point-to-multipoint configuration is established between the server 5 and the subscriber B. AT
The M path (401) is set.

When the point-to-multipoint ATM path is set up between the subscriber B and the server, the information of the channel requested by the subscriber will be transmitted to the subscriber via this path. However, as described above, in the near VOD service of the present invention, the process of transmitting information to the subscriber is not immediately started. In the process 40, the timer 52 is activated, and the timer 52 is activated until the program start time of the program requested by the subscriber is reached. Process 4
In No. 1, after the timer 52 expires, the communication processing function unit 5c of the server sends a service information transmission request to the server main control unit 5a (G). Upon receiving this signal, the server main control unit 5a sends a command to the subscriber to send service information to the storage device 5b of the server (H). The information of the requested channel is transmitted from the server to the subscriber 1b via the point-to-multipoint ATM path set in the above procedure (I). The system provides the services to the subscribers A and B by the above procedure.

Next, near video on
Another embodiment of the demand system will be described with reference to FIG. FIG. 5 shows the flow of another embodiment. In this embodiment, the server 5 is composed of a first server and a second server, and the server 5 shows an example in which movies of the same content are broadcast on the channels CH1 and CH2 at regular intervals, for example, every 30 minutes. There is.

Even if the first 10 minutes are missed, there are many cases in which the 10 minutes have been digested by subtitles or preludes depending on the movie broadcast on near VOD. Therefore, in the present embodiment, the server stores the number of minutes after the start of broadcasting the actual start time of the story (hereinafter, abbreviated as the actual start time) for each channel. In such a system, the channel CH that the subscriber has
When it is assumed that the request for 2 viewing is accessed to the server 1 at time 12:05 (501), the time 12:05 at that time is stored in the subscriber time table 53 of the communication function processing unit 5c. This time is the broadcast start time 1 of channel CH2.
Since it is well before 2:30, the subscriber has to wait until the broadcast start time 12:30 of channel CH2. On the other hand, since the broadcasting has already started on the channel CH1, the subscriber once selects the channel C.
If H2 is selected and then channel CH1 is selected, an extra charge will be charged for the first selection of channel CH2. Therefore, the server 1 determines whether or not the access time of the subscriber in the communication processing function unit 5c is before or after the actual start time of the channel CH2, and the subscriber is normally 2
We plan to wait for 5 minutes to watch channel CH2, so server 1 asks the subscriber to "skip?
/ N) ”. If the subscriber permits the skip, the server 1 activates a process of providing the subscriber with channel CH1 which has started broadcasting from 12:00 (503) (the specific flow at this time is already shown in FIG. 3). I explained using). In this case, if the channel CH2 selected first is not charged, the subscriber can watch the program selected by him / herself from almost the beginning, and the waiting time can be minimized. In addition to being able to do so, the problem of double billing is solved.

If the subscriber rejects the skip due to the above message, the switching process from the first server to the second server is started by the time the broadcasting starts at 12:30 (504). . The subscriber has a second server and A that store commercials and other software until the broadcast start time.
When it is connected by the TM path and the broadcast start time reaches 12:30, the switching process from the second server to the first server 1 is started again (505), and the first server and the subscriber who accessed first are In the meantime, the ATM path is reestablished and the first server provides the requested channel CH2 service to the subscriber.

As described above, the server has a plurality of program channels, and each channel converts the image information and audio information of the program into ATM cells at predetermined intervals (for example, 30 minutes). Send to subscriber, but ATM
When realizing near-VOD service on the network, it is necessary to consider the method of setting the ATM path and the method of processing the request for viewing the program by the subscriber. The system according to the present invention constructed as described above will be evaluated.

First, the path setting method will be evaluated. Instead of the conventional method of distributing cells from the server to the subscribers by broadcasting and selecting only the cells requested by the subscribers, the server 5 receives the service viewing request from the subscribers and then the server 5 Communication processing function unit 5c processes the subscriber's service request signal and transmits an ATM path connection permission signal to the subscriber, thereby establishing a point-to-multipoint ATM path between the server and the subscriber. The Switched Virtual Circuit (SVC) connection method is used. Therefore, when the path is connected between the server 5 and the subscriber, the ATM cell of the service information requested by the subscriber can be received from the server 5 through the connection and the program can be viewed. With this method, only the subscriber requesting to view the program can send an AT to the server 5.
Since the M path is set, the service information requested by the subscriber can be provided only to the subscriber who needs to transmit the ATM cell.

Further, when a program viewing request is transmitted from another subscriber to a program selected by one subscriber, the ATM between these subscribers and the server 5 is sent.
Path setting is point-to-multipoint configuration A
The TM path connection configuration is used. That is, in the ATM path initially set between the server and the subscriber, the virtual path identifier (VPI) / virtual channel identifier (VC) between the subscriber exchange accommodating the subscriber and the subscriber terminal.
The ATM path parameters such as I), bandwidth and quality of service (QoS) have the same values as the ATM path parameters of other subscribers and subscriber exchanges.

In this way, when a plurality of subscribers send a request for viewing a program in the same time zone to the server,
An ATM path with a point-to-multipoint configuration is set between the server and each subscriber, and when the program broadcast start time is reached, a signal from the timer of the communication function processing unit is sent to the main control unit of the server. Then, the server provides each subscriber terminal with a broadcast type ATM cell containing program information. By adopting this connection method, the point-to-point connection from the server to the subscriber exchange is possible.
Since the point-configured ATM path is set and the same ATM path is set from the subscriber exchange to the subscriber terminal, the server requests the subscriber only for the subscriber requesting to watch the program. The information of the service that has been created can be transmitted in the form of ATM cells. Then, the ATM distribution switch of the subscriber exchange only needs to distribute the minimum required ATM cells to the subscriber terminals, and the load on the switch can be reduced.

Next, a method of processing a request signal for a subscriber to watch a program will be evaluated. When a plurality of subscribers send a viewing request signal to the server for the same program, this signal is received by the communication function processing unit of the server, and the time at which the subscriber sends the viewing request is determined by the communication processing function unit 5c. It is stored in the subscriber time table 53 owned by. The main control unit 5a of the server 5 is notified of the time difference between the time stored in the time table 53 and the broadcast start time of the program requested by the subscriber, and the timer 52 is started. While the timer 52 is running, the communication processing function unit 5c of the server 5 can receive a viewing request signal from another subscriber. If a signal requesting viewing of the same program is received from another subscriber during this period, the communication processing function unit 5c causes the channel information storage unit 5 to operate.
5, the channels of the program requested by the subscriber who has accessed later and the program for which connection processing has already been completed are compared, and if they are the same program, the communication processing function is performed for this subscriber. The unit 5c transmits a message for point-to-multipoint ATM path connection processing.

When the subscriber sends a request for viewing the same program as a certain program to the server, the time at that time is stored in the subscriber time table 53 of the communication function processing section 5c. If you missed the first 10 minutes of some movies, well before the time (for example, if the channel interval was 30 minutes and the subscriber accessed the program at 2:30 on the 2:10). However, that 10 minutes are often digested by subtitles and preludes. Therefore, for each program, the server stores the number of minutes after the start of broadcasting that is the actual start time of the story (hereinafter, abbreviated as the actual start time). Since the subscribers normally plan to wait 20 minutes to watch the program, the server sends a message to the subscriber, "Do you want to skip and start watching now?" For example, the server initiates the process of providing the subscriber with another channel that begins airing at 2:00. By not charging the initially selected channel, the subscriber can watch the program he / she has selected almost from the beginning, and can minimize the waiting time. If the subscriber refuses, the server switching process is activated by the time the broadcast starts at 2:30.

In this case, the subscriber is required to enter the second server A that has stored commercials and other software until the broadcast start time.
It is connected with the TM pass, and when the broadcast start time is reached, the first time starts again.
The process of switching to the server is started, an ATM path is set up between the first server accessed first and the subscriber, and the server provides the service of the requested program to the subscriber.

[0035]

As described above, the near V of the present invention
The OD / system has the following effects.

(1) By setting the ATM path between the subscriber and the server in a point-to-multipoint configuration, the resources of the ATM network such as the band between the server and the ATM switch accommodating the server Can be saved.

(2) By setting the method of setting the ATM path between the server and the subscriber to be SVC instead of PVC, the load on the ATM distribution switch of the subscriber exchange can be reduced and the scale of hardware can be suppressed. it can.

(3) Instead of the method in which the subscriber extracts the ATM cells transmitted from the server in the broadcast type, the server transmits the service information only to the subscriber who has requested the service provision, Can centrally manage which service the subscriber is viewing.

(4) Since the communication processing function section of the server has a timer function, it is possible to provide a service channel in a time zone most suitable for the subscriber.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a near video on demand system according to the present invention.

FIG. 2 is a block diagram showing an internal structure of a communication function processing unit 5c.

FIG. 3 is an operation flow diagram when a subscriber requests channel viewing.

FIG. 4 is an operation flow diagram when a plurality of subscribers make a viewing request for the same channel.

FIG. 5 is a time chart for explaining another embodiment of the present invention.

[Explanation of symbols]

1a, 1b subscriber terminal 2 subscriber accommodating ATM switch (subscriber accommodating ATM node) 3 ATM network 4 server accommodating ATM switch (server accommodating ATM node) 5 server 5a server main controller 5b storage device 5c communication function processor 51 call Control unit 52 Timer 53 Subscriber time table 54 ATM connection table 55 Channel information storage unit

Claims (3)

[Claims] 1. A server accommodating ATM node accommodating a server having a storage device for accumulating service information, a subscriber accommodating ATM node accommodating a subscriber, and a subscriber terminal, wherein the server accommodating ATM node and the subscription are provided. Person A
In a near video on demand system in which a TM node is connected via an ATM (asynchronous transfer mode) network, transmission of service information requested by a subscriber from the server to the subscriber is started. If the server receives a request for receiving the same service from another subscriber by the time, the communication processing function unit of the server sends a message of the multipoint ATM path connection request for the same service information to the certain subscriber. And other subscribers, and a multi-point ATM path is connected before the start time of transmission of service information, near video on demand system. 2. A server accommodating ATM node accommodating a server having a storage device accumulating service information, a subscriber accommodating ATM node accommodating a subscriber, and a subscriber terminal, wherein the server accommodating ATM node and the subscription are provided. Person A
In a near video on demand system in which a TM node is connected through an ATM (asynchronous transfer mode) network, the server accommodating ATM node is a storage device capable of providing a plurality of service channels and an ATM from a subscriber.
A plurality of servers each having a communication function processing unit for processing a path connection request and having a function of providing respective service information are accommodated, and service information requested by a subscriber starts to be transmitted from the server to the subscriber. The communication function processing unit of the server calculates the waiting time until the transmission starts, and activates the switching process of the server between the communication processing function unit of the server and the communication processing function unit of another server. Using the idle time until the server starts transmitting the service information to the subscriber terminal, the ATM path of the other server and the subscriber is set, and when the idle time becomes short, the communication processing function unit of the server is restarted. The server switching process is started between the server and the communication processing function unit of another server, and the server is connected to the subscriber's path to require the subscriber. Near video-on-demand system and providing the service information. 3. A server accommodating ATM node accommodating a server having a storage device for accumulating service information, a subscriber accommodating ATM node accommodating a subscriber, and a subscriber terminal, wherein the server accommodating ATM node and the subscription are provided. Person A
In a near video on demand system in which a TM node is connected via an ATM (asynchronous transfer mode) network, the server accommodating ATM node is a storage device storing a plurality of service information and an ATM path from a subscriber. A plurality of servers having a communication function processing unit for processing connection requests and having a function of providing respective service information are accommodated, and the servers provide certain service information to subscriber terminals through the ATM network at regular time intervals. The subscriber terminal sends a request for setting an ATM path to the server to the ATM network and receives service information to be selected by connecting the server with the ATM path.
When a plurality of subscriber terminals transmit a service request signal in the same time zone to the server, the communication processing function unit of the server detects the time when each of the subscribers transmits the service request signal and detects the time. The time is stored in the time table of the communication processing function unit and compared with the start time of the requested service information, and the service request time from the plurality of subscribers is within a specified time after the service information is started to be provided. For the subscribers who have searched for the request and sent the service request within the specified time, the communication processing function unit of the server multipoints A to these subscribers.
A near video on demand system characterized by transmitting a signal of TM path connection and connecting the same path as the ATM path already connected at the service start time to the server.