JP2003188920A - Video repeater and repeating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a video repeater for continuing a normal transfer operation without interrupting an image by instantaneously switching a failure video repeater and a transmission line to auxiliary ones. <P>SOLUTION: The video repeater is provided with a plurality of packet input/ output means 101 for inputting/outputting a video packet, a packet transfer means 102 for transferring the inputted video packet to another packet input/ output means, a packet transfer report input/output means 104 for reporting the transfer of the video packet and a control means 105 for analyzing the contents of the video packet, deciding the failure of another video repeater and switching the operation modes of the video repeater when a failure occurs. The control means transfers the video packet to a transmission destination when the operation mode of the self video repeater is a transfer mode, receives a packet transfer report from another video repeater and determines failure occurrence in the case of a standby mode and, then, switch the operation mode to the transfer mode to transfer the video packet when the failure occurrence is determined. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video relay apparatus which prepares a plurality of transmission lines and switches and uses the transmission lines when a failure occurs.

[0002]

2. Description of the Related Art Conventionally, a monitoring network system disclosed in Japanese Patent Laid-Open No. 10-136346 is known. A conventional monitoring network system as shown in FIG. 6 includes a video transmitting device 2 for transmitting a video through a network, a video receiving device 3 for receiving and displaying the video, and a video transmitting device 2 and the video receiving device 3 between them. And a hub 4 for connecting and relaying the transmission lines of the above. The video transmission device 2 converts the acquired video into packetized digital data and transmits it through the network. The video receiving device 3 receives the video packet, reconstructs the video data, and displays it. A bus type or a star type is used for the network form. The video receiving device 3 and the video transmitting device 2 are separated from each other, and the video packets of the video transmitting devices 2 adjacent to each other are aggregated and transmitted in one transmission path. When the transmission path is physically or logically disconnected due to a failure, the images of all the image transmitting devices cannot be displayed.

In addition, IP over Ethernet (registered trademark)
As a method for improving availability by duplicating a relay device such as a router and a network connecting device such as a server in a network system for transmitting data based on the above, a method described in JP-A-08-172449 is known. ing. In such a system, 2
When a failure occurs in one of the duplicated devices, the operation of switching to the other waiting device is performed. At this time, as a method of changing the setting of the network interface, IP address replacement called IP address takeover is performed. When a failure occurs in the main relay device, the ARP table, which is a correspondence table of the IP address or the IP address of the video transmission device and the physical address, is corrected to switch the video data transmission destination. This switching of the transmission destination must be performed by all video transmission devices.

In this system, the detection of the failure and the implementation of the countermeasure are intended only when the transmission is stopped due to the failure, and when the transmission rate of the video data which needs to maintain a constant transmission rate is lowered due to the failure. Means that the normal operation is continued while the image reproduced by the image receiving device is disturbed.

[0005]

However, in the above-mentioned conventional surveillance network system, when the image pickup network and the monitor network are connected by one physical transmission line, the video data is caused by a failure of the transmission line. There was a problem that you could not receive. In addition, even when connected by a plurality of transmission paths, it is necessary to switch the setting of the transmission destinations of all video transmission devices that transmit video data, and after the switching is completed,
There is a problem that it takes time for the monitor device to be able to receive the images of all the imaging devices, and the image displayed on the receiving terminal is interrupted.

[0006] Further, the detection of the failure and the implementation of the countermeasure in the general network device are intended only when the transmission is stopped due to the failure, and the transmission rate of the video data for which the constant transmission rate needs to be maintained depends on the failure. If it decreases, there is a problem that the transfer operation is continued with the video reproduced by the video receiving device being interrupted.

The present invention has been made in order to solve the conventional problem. Immediately switching a faulty relay device or transmission path to a spare one allows a normal transfer operation to continue without interruption of the image. A video relay device and a relay method capable of performing the same are provided.

[0008]

A video relay apparatus according to the present invention comprises a plurality of packet input / output means for inputting / outputting a video packet and another video packet input to the packet input / output means according to its destination. Packet transfer means for transferring to the packet input / output means, packet transfer notification input / output means for notifying the transfer of the video packet, content of the input video packet is analyzed to determine a failure in the transfer of the video packet, and a failure occurs. And a control means for switching the operation mode, wherein the control means transfers the input video packet to the destination when the operation mode of the own device is the transfer mode, and the packet transfer notification input / output means in the standby mode. A failure occurrence is determined from the packet transfer notification received from the outside via the It has a configuration that has a function of switching. With this configuration, the video packet is transferred in the transfer mode, the packet transfer notification is received in the standby mode, and when it is determined that a failure occurs, the standby mode is switched to the transfer mode and the normal video packet is immediately transmitted. Can be transferred.

The video relay apparatus according to the present invention transfers a plurality of packet input / output means for inputting / outputting a video packet and the video packet input to the packet input / output means to another packet input / output means depending on the destination of the packet. Packet transfer means for analyzing the contents of the input video packet, determining a failure in the transfer of the video packet, and switching the operation mode when the failure occurs. In the case of standby mode, the input video packet is transferred to the destination. In the standby mode, the video packet transferred from the source of the video packet is received, and the transfer rate of the received video packet is calculated to determine the failure occurrence When it is determined to occur, it has a function of switching the operation mode to the transfer mode. With this configuration, the video packet is transferred in the transfer mode, the video packet transferred by the video relay device operating in the normal mode is received in the standby mode, the transfer rate is calculated, and the failure occurrence is determined. When it is determined that a failure has occurred, the standby mode is immediately switched to the transfer mode, and the video packet can be transferred.

In the video relay apparatus according to the present invention, the control means receives the video packet transferred from the video relay apparatus operating in the normal transfer mode, and determines the transfer rate from the transfer data amount of the received video packet per unit time. And has a function of determining that a failure has occurred when the data amount per unit time of the video data set at the time of encoding the video data is equal to or less than a threshold value.
With this configuration, it is possible to determine that a failure has occurred when the transfer amount of video packets is small.

In the video relay apparatus according to the present invention, the control means receives the video packet transferred from the video relay apparatus operating in the normal transfer mode via the packet input / output means, and the received video packet per unit time. The transfer rate is calculated from the transfer data amount of
Receives a video packet addressed to a video relay device operating in the normal transfer mode, obtains the reception rate as the data amount per unit time, the data amount per unit time set at the time of encoding the video data becomes less than or equal to the threshold value, In addition, when the reception rate is equal to or higher than a threshold value, the video relay device operating in the normal mode has a function of determining that a failure has occurred. With this configuration, it is possible to determine that a failure has occurred when the transfer amount of video packets is small despite the input of the amount of data to be transferred.

In the video relay device according to the present invention, the video receiver, which is the destination of the video packet, receives the video packet addressed to the video relay device operating in the normal transfer mode, and obtains the reception rate as the data amount per unit time. A buffer remaining amount warning packet is transmitted from the video receiving device when the remaining amount of the video packet in the buffer of the video receiving device for receiving the video packet becomes equal to or less than a threshold value, and the control means of the video relay device receives the buffer remaining amount. When the buffer amount warning packet is received when the amount warning packet is received and the reception rate of the received video packet is equal to or higher than the threshold value, it has a function of determining a failure. With this configuration, it is possible to determine that a failure has occurred when the amount of data to be transferred has not been transferred to the receiving device even though the amount of data to be transferred has been input, and the amount of buffer for holding video data of the receiving device has decreased. it can.

The video relay device according to the present invention adds the initial storage capacity of the video packet and the received data capacity obtained from the data amount of the transfer packet in the video receiving device within a certain period, and obtains it from the bit rate of the video data. A buffer remaining amount calculating means for calculating an estimated remaining amount of video data of the video receiving device obtained by subtracting the obtained data consumption amount, and the control means is transferred from the video relay device operating in the normal transfer mode. Video packet is received, the transfer rate is calculated from the transfer data amount of the video packet per unit time, the packet transfer notification is not received even if it exceeds the specified time, and the video data remaining amount calculated by the buffer remaining amount calculation means is calculated. When the estimated amount of remaining video data is less than the data amount for failure determination reference when comparing the amount estimation value and the data amount for failure determination reference, It is determined that the failure of the video relay device has a configuration that has a function of switching the operation mode of the video relay device. With this configuration, even if the amount of data to be transferred is input, it is not transferred to the receiving device, and if it is estimated that the buffer amount of the receiving device for holding video data has decreased, a failure occurs. Can be determined.

In the video relay device according to the present invention, the packet transfer means detects an alarm packet in the video packet transferred from the video relay device operating in the normal transfer mode, and the control means operates in the normal transfer mode. The transfer rate is calculated from the transfer data amount per unit time of the video packet transferred from the video relay device, and the error judgment period is tightened during the alarm condition period from the reception of the alarm notification to the reception of the alarm cancellation notification. In addition, by increasing the threshold of the transfer rate, which is the failure determination criterion, compared to the normal state to increase the probability of determining an abnormality, a configuration is provided that has a function of suppressing the possibility of image display interruption in the video receiving device. is doing. With this configuration, during the alarm state period after the reception of the alarm packet, it is easier to determine the failure than in the normal time, and it is possible to suppress the video packet transfer suspension period when the failure occurs.

In the video relay apparatus according to the present invention, when the control means determines that there is a failure in the transfer of the video packet received from the outside, a proxy for receiving and transferring the video packet from the source of the failed video packet. The transfer mode is set, and in the proxy transfer mode, it has a function of receiving a video packet of the same destination as the video packet in which the failure has occurred and transferring it by proxy. With this configuration, it is possible to suppress the period in which the video packet is interrupted and the video transmission is interrupted even before the switching is completed.

The video relay apparatus according to the present invention is set to a proxy transfer mode in which the control means receives and transfers the video packet transmitted from the source of the video packet determined to have an external failure by the control unit. Then, a notification of modification of the destination information is issued to the video transmitting device that transmits the video packet, and if the video packets from all the video transmitting devices are sent to the self-video relay device, the self-video relay device is activated. It has a configuration having a function of shifting to the normal transfer mode. With this configuration, it is possible to suppress the period in which the video packet is interrupted and the video transmission is interrupted even before the switching is completed.

The video relay apparatus according to the present invention has a list of video packets that pass the video packets received by the control means, measures the reception rate of packets that do not match the list, and detects the video packets existing in the list. Even if the transfer rate is lowered, if the reception rate of the packets that do not match the list is high, it is not judged as a failure of the video relay apparatus but has a function of notifying a warning packet. With this configuration, only the warning can be issued without switching the video relay device when the transmission line is congested.

A program according to the present invention causes a computer to function as a part or all of each means in the video relay apparatus according to any one of claims 1 to 10.
The computer is configured to realize some or all of the functions of the video relay apparatus according to any one of claims 1 to 10. With this configuration, each means or function in the video recording / reproducing apparatus of the present invention or each step in the video recording / reproducing method can be programmed and easily implemented by a computer.

A computer-readable recording medium according to the present invention has a structure for recording the program according to claim 11. With this configuration, each unit or function in the video recording / reproducing apparatus of the present invention or each step in the video recording / reproducing method is programmed and recorded in a computer-readable recording medium, so that the present invention can be performed by another computer. It can be easily implemented.

A video monitoring network system according to the present invention includes a plurality of video transmitting devices for packetizing and transmitting the captured video, a video receiving device for receiving and displaying the video packets, a network including the video transmitting device, and A plurality of video relay devices for relaying to and from a network including a video receiving device, wherein the video relay device detects packet transfer of another video relay device to determine its failure,
When it is determined that there is a failure, it has a function of switching the operation modes of both of the video relay devices. With this configuration, when a failure occurs in the video relay device or the transmission path between the networks, failure recovery can be performed so that the video is not interrupted, and availability can be improved.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The first to tenth embodiments of the present invention will be described in detail below with reference to the accompanying drawings. (First Embodiment) Next, a video relay apparatus according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows the configuration of the video relay device 1,
FIG. 2 shows the configuration of a video surveillance network system using the video relay device 1. The video relay device 1 shown in FIG.
One or more packet input / output units 101a and 101b for inputting / outputting data packets to / from the network
And a packet transfer means 102 for transferring the input video packet to another packet input / output means 101 with or without conversion of the destination information based on the destination information or the source information, and a packet transfer means or a packet transfer at a constant interval. A packet transfer notification input / output unit 104 that transmits or receives a transfer notification, and a control unit 105 that detects a failure occurrence in another video relay apparatus 1 and switches the operation mode when a failure occurs.

In the embodiment of the present invention, IEEE80
It is assumed that data is transmitted based on the Internet Protocol (IP) and the User Datagram Protocol (UDP) by Ethernet, which is the network defined in 2.3. It should be noted that another transmission medium such as IEEE 1394 or a protocol other than ID or UDP may be used. The packet input / output units 101a and 101b are ports for transmitting / receiving Ethernet frames. The packet transfer notification input / output unit 104 according to the present embodiment is connected to another video relay device 1 and is independent of the network through which the video packet flows, and is connected by another transmission unit that performs Ethernet or serial transmission. .

FIG. 2 is a diagram showing an example of a video transmission network system using the video relay device 1 according to the embodiment of the present invention. The video relay device 1 (1a in FIG. 2) normally operated.
And a video relay device 1 (1b in FIG. 2) connected as a spare, and video transmission devices 2a to 2f for transmitting video as packetized digital data.
And a video receiving device 3 for receiving and displaying video packets
a, 3b and hubs 4a to 4 for relaying and switching transmissions
It consists of c and. The image transmitters 2a to 2f may include image pickup means, and the image relay devices 1a and 1b perform relay between the image pickup system network on the transmission side and the monitor network on the reception side. In addition, a plurality of video relay devices 1a and 1b may be prepared and the transmission paths between networks may be multiplexed.

Next, the operation of the video relay apparatus according to the first embodiment of the present invention will be described with reference to FIGS. The video relay device 1 (1a, 1b) has at least two modes: a normal transfer mode and a standby mode.
In the normal transfer mode, the control unit 105 notifies the packet transfer unit 102 of the start of transfer and starts the transfer of video packets.

Now, it is assumed that the video relay apparatus 1a is operating in the normal transfer mode. The packet input / output unit 101a of the video relay apparatus 1a operating in the normal transfer mode receives the video packet passing through the video relay apparatus 1a. The received video packet is sent to the packet transfer means 102, the destination information or the source information included in the packet is referred to, and one or both of the destination information and the source information is used by using the information conversion table and one or both of the destination information and the source information. Is converted and sent to the packet input / output unit 101b. Here, the destination information or the source information includes either or both of a physical address such as an Ethernet address and a logical address such as an IP address. For example, an operation of converting a destination address into a multicast address addressed to a group of receiving terminals based on a table in which the destination information is a unicast address and is associated with the receiving logical port number and the multicast address Is done. When the video relay devices 1a and 1b operate as simple switches and have a plurality of packet input / output means, they are transferred unconverted to the packet input / output means connected to the destination according to the destination information. As the transfer processing, processing such as routing by a router or gateway, packet filtering, protocol conversion, etc. may be performed.

On the other hand, the packet transfer means 102 sends a transfer notification to the control means 105, and the control means 105 holds the cumulative value of the number of transfers for each destination information or transmission source information. The control unit 105 outputs a packet transfer notification to the other video relay apparatus 1b via the packet transfer notification input / output unit 104 for each specified packet transfer. The above operation is repeated in the normal transfer mode.

Video relay device 1 operating in standby mode
The packet transfer means 102 of b does not transfer the packet. Packet transfer notification input / output unit 1 of the video relay apparatus 1b
04 receives the packet transfer notification from another video relay device 1a operating in the normal transfer mode, and the control means 10
Notify the reception to 5. The control unit 105 monitors the occurrence of a failure in the video relay device 1a, which is the transmission source, from the received packet transfer notification. When it is determined that a failure has occurred, the operation mode of the video relay device 1b in the standby mode is switched to the normal transfer mode, and the packet transfer means 102 is instructed to start the transfer. At this time, the IP address of the video relay device 1b operates with the same setting as that of the video relay device 1a, and to the video transmission devices 2a to 2f which transmit the packet passing through the video relay device 1a or 1b,
Notify the update of the ARP table.

Next, the detection of failure occurrence will be described in more detail. The video relay device 1a in the normal transfer mode transmits a packet transfer notification every specified number of packet transfers. When the number of packet transfers received per unit time falls below the threshold value, the video relay device 1b in the standby mode operates in the normal transfer mode.
It is determined that a failure has occurred. The threshold is calculated by dividing the coding bit rate of video data by the amount of data in the packet, assuming that the video packet has a fixed length.Fault determination is performed from the start to the end of transmission. And the transmission ends when the video transmission device 2a
2f may notify. In addition, when the video relay device 1a in the normal transfer mode issues a normal operation notification at regular time intervals and the video relay device 1b in the standby mode does not receive the normal operation notification even if the threshold time is exceeded during the other periods. It may be determined that there is a failure.

In the above description, the video relay device 1b is used.
Is a failure determination and other video relay device 1 in the standby mode.
Although the switching from a is performed, all of the plurality of video relay devices 1 operate in the normal transfer mode to reduce the load of video packet transfer, the failure determination is performed in the normal mode, and the video relay device 1a or 1b is selected. When a fault occurs, the faulty video packet transferred by the video relay device 1a may be additionally transferred by the video relay device 1b operating normally.

It is to be noted that video packet transmission / reception processing, processing for transferring an input video packet to another packet input / output means with or without conversion of destination information based on destination information or source information, transferred video Processing to analyze packet and collect transfer history information of video packet,
Either or all of the processing for controlling the transmission or reception of the packet transfer notification during packet transfer or at regular intervals, the processing for detecting the failure occurrence of another device and switching the operation mode when the failure occurs may be performed by software. good.

As described above, according to the video relay apparatus in the first embodiment of the present invention, the packet transfer notification input / output means 104 for transmitting or receiving the packet transfer notification, and the packet transfer notification time interval. By providing a control unit 105 that detects a failure occurrence in another device and switches the operation mode when a failure occurs, it is possible to automatically recover from the failure occurrence. Further, even if the packet transfer is not completely stopped due to the occurrence of a failure, the video relay device that transfers the video packet can be switched even when the transfer rate is reduced, and the recovery can be performed while suppressing the time when the video is interrupted.

(Second Embodiment) Next, a video relay apparatus according to a second embodiment of the present invention will be described with reference to FIGS. The components of the video relay apparatus 1 according to the present embodiment shown in FIGS. 1 and 2 are the same as those in the first embodiment, and thus the description thereof will be omitted.
In the present embodiment, the failure occurrence is detected based on the transfer rate in the normal transfer mode. The video packet received by the packet input / output unit 101a is sent to the packet input / output unit 101b for outputting the video packet via the packet transfer unit 102. On the other hand, the packet transfer means 102 obtains the net video data amount inside the packet and notifies it to the control means 105, and the control means 105 holds the cumulative value of the transfer data amount for each destination information or transmission source information. The control means 105 sends a packet transfer notification to the packet transfer notification input / output means 104 each time data is received once or a plurality of times. The packet transfer notification input / output unit 104 sends the packet transfer notification to the video relay device 1b in the standby mode.
Output to. The above operation is repeated in the normal transfer mode.

The video relay device 1a in the normal transfer mode transmits a packet transfer notification including the transferred video data amount to the video relay device 1b in the standby mode at a fixed time interval or during packet transfer. The control means 105 of the video relay device 1b calculates the video transfer rate from the data amount of the packet passing within the unit time for each destination address or transmission destination address from the received packet transfer notification.
A failure determination threshold having a value less than or equal to the data amount per unit time set at the time of encoding the video data is set in the control unit 105, and the control unit 105 determines that the video transfer rate is below the failure determination threshold. Judge as a failure.

When a video packet is not being transmitted, an operation confirmation notification is given at regular time intervals, a video transmission start packet is detected, and the transfer rate is determined to be lower when the video packet is received for the first time after receiving the packet. To do so. Further, the transmission timing of the packet transfer notification may be notified at a fixed time interval instead of the packet transfer count. Although the present embodiment is used in a network for transmitting video, it may be used in a network for transmitting data such as audio other than video.

As described above, according to the second embodiment of the present invention, the packet transfer notification input / output means 104 for transmitting or receiving the packet transfer notification, and the occurrence of a failure in another device depending on the video transfer rate. And a control means 105 for switching the operation mode when a failure occurs to switch the video relay device that transfers the video packet by the transfer rate reduction even if the packet transfer is not completely stopped due to the failure. It is possible to perform recovery while suppressing the interruption time.

(Third Embodiment) Next, a video relay apparatus according to a third embodiment of the present invention will be described with reference to FIGS. The components of the video relay apparatus 1 according to the present embodiment shown in FIGS. 1 and 2 are the same as those in the first embodiment, and thus the description thereof will be omitted.

In the present embodiment, the packet input / output unit 101a of the video relay apparatus 1b in the standby mode operates in the normal transfer mode other than the destination of the video relay apparatus 1b.
Receives the video transfer packet addressed to. The packet transfer means 102 obtains the net video data amount inside the packet and notifies it to the control means 105, and the control means 105 holds the cumulative value of the received data amount for each destination information or transmission source information,
For each destination address or destination address, the video reception rate is calculated from the data amount per unit time of the video packet received per unit time and recorded. Also, the transfer rate is held as in the second embodiment. The control means 105 compares the video reception rate calculated from the received video packet with the video transfer rate calculated from the packet transfer notification, and the video transfer rate is equal to or lower than the video reception rate and the video data is encoded. When the value is below the failure determination threshold value set below the data amount of the video data set per unit time, the failure is determined.

As described above, according to the third embodiment of the present invention, the control means 105 of the video relay apparatus 1b in the standby mode calculates the video reception rate, and the control means 105 calculates the video reception rate. And the video transfer rate from the video relay device 1 operating in the normal transfer mode,
By detecting the occurrence of a failure in the device and controlling the operation mode to switch when a failure occurs, even if the packet transfer is not completely stopped due to the failure, the device that transfers the video packet is switched due to the decrease in the transfer rate. It is possible to perform recovery while suppressing the interruption time.
In addition, the video relay device 1 in which the failure detection process is in the standby mode
By carrying out in step b, the processing amount of the video relay device 1 in the normal transfer mode can be reduced. Further, only when there is a failure in the video relay apparatus 1 and the transmission path directly connected to the video relay apparatus 1, it is possible to determine the failure and switch the operation mode.

(Fourth Embodiment) Next, a video relay apparatus according to a fourth embodiment of the present invention will be described with reference to FIGS. In FIG. 3, a packet transfer notification input / output unit 104 for transmitting / receiving a packet transfer notification.
Is connected to one or more packet input / output units 101b for inputting / outputting video packets to / from the network. Other than that, the components of the video relay apparatus 1 in the present embodiment shown in FIG. 3 are the same as those in any one of the first to third embodiments, and therefore the description thereof will be omitted.

In the present embodiment, the video relay apparatus 1a in the normal transfer mode transfers video packets, but does not perform packet transfer notification, as in each of the first to third embodiments. The video relay device 1b in the standby mode is the video relay device 1 operating in the normal transfer mode.
The video packet transferred from a is packet input / output means 10
Received at 1b. The received video packet is sent to the packet transfer means 102, the packet contents are analyzed, and if it is addressed to the video relay device 1a operating in the normal transfer mode,
The packet transfer means 102 obtains the net video data amount in the packet and notifies the control means 105. Control means 1
Reference numeral 05 holds the cumulative value of the transfer data amount for each destination information or transmission source information. Further, the control unit 105 determines the occurrence of a failure by the same method as in each of the first to third embodiments, and the video relay device 1 operating in the normal mode.
When it is determined that a failure has occurred in a, a process of switching the video relay device 1b in the standby mode to the normal transfer mode is performed, and another video relay device is sent via the packet transfer notification input / output unit 104 and the video relay device 1b. It outputs a packet transfer notification to 1b.

According to the present embodiment, when the video packet flows mainly in only one direction, it goes in the opposite direction, that is, from the video receiving devices 3a and 3b side to the video relay device 1b in the standby mode. Transmission amount (control signal) is small. Video packets for failure determination can be flowed there to be effectively used, and the dedicated transmission path between the video relay devices 1a and 1b can be omitted. Further, by letting the video relay device 1b, which has not transferred the video packet in the standby mode, perform all the process of the failure determination, it is possible to reduce the processing load of the video relay device 1a in the normal transfer mode.

As described above, according to the fourth embodiment of the present invention, the video packet transferred by another video relay apparatus 1 is analyzed to calculate the transfer rate of the video packet,
By providing the control means 105 that detects the occurrence of a failure in another device based on the video transfer rate and switches the operation mode when a failure occurs, even if the transfer rate is reduced even if the packet transfer is not completely stopped due to the failure occurrence, It is possible to switch the video relay device that transfers the video packet and perform restoration while suppressing the time when the video is interrupted.

(Fifth Embodiment) Next, a video relay apparatus according to a fifth embodiment of the present invention will be described with reference to FIGS. 1 to 3,
The packet transfer means 102 of the video relay device 1 according to the present embodiment is configured to include a buffer remaining amount warning receiving means for receiving the buffer remaining amount warning notification from the video receiving devices 3a and 3b. In addition, each component of the video relay apparatus 1 according to the present embodiment is the same as that of any one of the first to fourth embodiments, and thus the description thereof will be omitted. now,
The video relay device 1b in the standby mode receives the video packet transmitted to the video relay device 1a operating in the normal transfer mode, analyzes the packet contents, and calculates the reception data rate. At the same time, the buffer remaining amount warning receiving means of the packet transfer means 102 monitors the video packet addressed to itself from the video packets received by the packet input / output means 101b on the video receiving device side, and inputs the video packet to the video relay device 1b. Among them, the packet remaining amount warning packet transmitted from the video receivers 3a, 3b is identified, and when the packet remaining amount warning packet is received, the packet remaining amount warning notification is sent to the control means 105. When the packet residual amount warning notification is received even though the received data rate is equal to or higher than the threshold value, the control unit 105 determines that a failure has occurred and switches the operation mode from the standby mode to the normal operation mode.

In the above description, the failure determination is made by using the information of the received data rate, but the operation mode may be switched only by the buffer remaining amount warning notification. In addition, in order to avoid switching the operation mode by sending an incorrect packet remaining amount warning packet, the operation mode may be switched only when the packet remaining amount warning packet is received from a plurality of devices. good.

As described above, according to the fifth embodiment of the present invention, the buffer remaining amount warning receiving means for receiving the buffer remaining amount warning notification from the video receiving devices 3a and 3b, and the buffer remaining amount warning. By providing a control unit 105 that detects the occurrence of a failure in another device by the notification and switches the operation mode when a failure occurs, a failure determination with increased accuracy is performed based on the actual buffer remaining amount of the video receiving device, and the receiving device It is possible to switch the video relay device 1 that transfers video packets before the remaining buffer capacity runs out, and perform recovery while suppressing video break times.

(Sixth Embodiment) Next, a video relay apparatus according to a sixth embodiment of the present invention will be described with reference to FIGS. 4 and 2,
The video relay device 1 according to the present embodiment is configured to include a buffer remaining amount calculating means 106 that calculates a remaining amount estimation value of the video data buffers of the video receiving devices 3a and 3b.
Other than that, each component of the video relay apparatus 1 according to the present embodiment is the same as that of any one of the first to fifth embodiments, and the description thereof will be omitted.

The video relay device 1b in the standby mode receives the video packet transmitted to the video relay device 1a operating in the normal transfer mode, analyzes the packet contents, and calculates the reception data rate. Further, similarly to the second embodiment, the video relay device 1b receives the video packet transferred by the video relay device 1a operating in the normal mode and calculates the transfer rate. Based on the received video packet, the buffer remaining amount calculation means 106 calculates a value obtained by adding the initial storage capacity of the video packet of the video receivers 3a and 3b within a certain period and the received data capacity obtained from the data quantity of the transfer packet. , The remaining data amount is calculated by subtracting the data consumption amount obtained from the bit rate of the video data. The remaining data amount is sent to the control means 105 and compared with the failure determination reference data amount. Although the control means 105 has the received data rate equal to or higher than the threshold value and has no abnormality,
When the remaining data amount is less than the failure determination reference data amount, it is determined that a failure has occurred, and the operation mode of the video relay device 1b is switched from the standby mode to the normal operation mode. This failure determination is performed for each transmission destination information or transmission source information of the video packet.

The function of the buffer remaining amount calculating means 106 can be realized by software. Further, the data amount of the transfer packet operating in the normal mode may be calculated from the packet transfer notification, as in the first or second embodiment. Also, to avoid switching the operation mode by sending an incorrect packet remaining amount warning packet, switch the operation mode only when it is determined that there is a failure in the video packets transmitted from multiple devices. You can

As described above, according to the sixth embodiment of the present invention, the buffer residual amount calculating means 106 for calculating the theoretical residual amount of the video data buffer of the video receiving device,
By providing the control means 105 that detects the occurrence of a failure in another device based on the remaining estimated data amount calculated by the video reception devices 3a and 3b and switches the operation mode when a failure occurs, the accuracy is determined by the buffer remaining capacity estimated value of the video reception device. It is possible to perform a failure determination with a higher level, switch the video relay device 1 that transfers the video packet before the buffer remaining amount of the video receiving devices 3a and 3b runs out, and perform the recovery while suppressing the video break time.

(Seventh Embodiment) Next, a video relay apparatus according to a seventh embodiment of the present invention will be described with reference to FIGS. 1 to 4,
The video relay apparatus 1 according to the present embodiment has a packet transfer means 102 having a function of detecting an alarm packet in a video packet to be transferred, and a control means 10 for making a failure judgment by tightening a failure judgment criterion when an alarm packet is detected.
5 is provided. In addition, each component of the video relay apparatus 1 according to the present embodiment is the same as that of any one of the first to sixth embodiments, and thus the description thereof will be omitted.

The video relay device 1b in the standby mode receives the video packet transmitted to the video relay device 1a operating in the normal transfer mode, analyzes the packet contents, and updates the received data rate. The packet transfer means 102 of the video relay device 1b identifies an alarm packet transmitted from another device such as the video transmission device 1a among the input packets, and when the alarm packet is received, notifies the control means 105 of alarm reception. I do. Here, the alarm packet is a packet that is issued when an abnormality occurs, for example, when an intruder detects it or when the transmission path is disconnected in the video surveillance system.
The control unit 105 of the video relay apparatus 1b raises the threshold value of the failure determination criterion for the video packet transmitted from the alarm packet transmission source so that the video packet is closer to the data rate at the time of video encoding than the threshold value at the normal time. When the reception data rate is equal to or higher than the threshold value and there is no abnormality in the reception, but the transfer data rate decreases, it is determined that a failure has occurred, and the operation mode is switched from the standby mode to the normal operation mode. The above operation is continued during the alarm state period from the reception of the alarm packet to the reception of the alarm release notification.

As described above, according to the seventh embodiment of the present invention, the packet transfer means 1 having the function of detecting the alarm packet informing that the abnormality has occurred.
02 and the control means 105 that makes a failure determination by stricting the failure occurrence criterion when an alarm packet is detected, so that the failure determination criterion is strict when an abnormality occurs, and the video relay device at an earlier stage than the normal time. It is possible to perform switching of No. 1 and to perform recovery while suppressing interruption of video when an abnormality occurs.

(Eighth Embodiment) Next, a video relay apparatus according to an eighth embodiment of the present invention will be described with reference to FIGS. 1 to 4,
The video relay device 1 according to the present embodiment is configured to include a control unit 105 that keeps the video relay device 1b in the standby mode in the proxy transfer mode until the destinations of all video packets are switched. In addition, the video relay device 1b is operated in the normal mode in the standby mode.
Receive a video packet via a. Other than that, each component of the video relay apparatus 1 according to the present embodiment is the same as that of any one of the first to seventh embodiments, and the description thereof will be omitted.

The video relay device 1b in the standby mode receives the video packet passing through the other video relay device 1a operating in the normal mode, and, as in the first to fifth embodiments, the normal operation is performed. It is monitored whether another video relay device 1a operating in the mode is operating normally. When the video relay device 1a is determined to be in failure, the control unit 105 switches the operation mode and shifts the video relay device 1b to the proxy transfer mode. In the transition mode to transition to the normal transfer operation mode,
The video relay device 1b continues to receive the video packet passing through the other video relay device 1a, and the video relay device 1b performs the transfer in place of the video relay device 1a which is determined to have a failure.

In order for the video relay device 1b in the standby mode to receive a video packet addressed to the video relay device 1a in the normal transfer mode, a plurality of video relay devices 1 are put together as a multicast group, and the video transmission devices 2a to 2f.
May be transmitted by multicast. Alternatively, the video transmission devices 2a to 2f to which the video relay devices 1a and 1b are connected.
A packet addressed to the video relay device 1a operating in the normal mode is copied to the hub on the side and transmitted to the video relay device 1b in the standby mode.

As described above, according to the eighth embodiment of the present invention, the video relay device 1b in the standby mode.
By providing the control means 105 for setting the proxy transfer mode for receiving the video packet addressed to the video relay device 1 in which the failure has occurred and transferring it instead, all the video transmitters 2a to 2f are switched by switching the video relay device 1. The video receiving devices 3a and 3b are not incapable of receiving some video packets until the change of the destination information is completed, and the video packets can be continuously received.

(Ninth Embodiment) Next, a video relay apparatus according to a ninth embodiment of the present invention will be described with reference to FIGS. 5 and 2,
The video relay device 1 according to the present embodiment is configured so that the video packet switching end determination unit 107 that determines that the switching of the video packet transfer from the video relay device 1a to the video relay device 1b has been completed, and the destinations of all the video packets are The control unit 105 keeps the video relay apparatus 1 in the normal transfer operation transition mode until it is switched. In addition, each component of the video relay apparatus 1 according to the present embodiment is the first
The description is omitted because it is the same as any of the eighth to eighth embodiments.

The video relay device 1b in the standby mode receives the video packet via the other video relay device 1a operating in the normal mode. Then, the video relay device 1b
Monitors whether or not the other video relay device 1a operating in the normal mode is operating normally, as in the first to fifth embodiments. Therefore, when it is determined that the video relay device 1a has a failure, the control unit 105 switches the operation mode of the video relay device 1b to the normal transfer operation transition mode.
In the normal transfer operation transition mode, the video transmitters 2a to 2f
To the video relay device 1b to notify the video relay device 1b of the switching of the operation mode, and switch the transfer of the video packet to the video relay device 1b. Along with that, another video relay device 1 continues
Video packets are also transferred via a. The video packet switching end determination unit 107 of the video relay device 1b monitors the source information and the destination information of the video packet to be transferred, and for each source of the received video packet, the destination is its own video relay device 1b. It is determined whether it has been switched. When the video packets from all the transmission sources are addressed to the own video relay device 1b, it is determined that the switching of all the video transmission devices 1 is completed, and the control unit 105 is notified of the destination switching completion. When the control unit 105 receives the destination switching end notification, the control unit 105 shifts the operation mode of its own video relay apparatus 1b from the normal transfer operation transition mode to the normal transfer mode, suspends the transfer to the other video relay apparatus 1a, and stops its own operation. Only transfer of a video packet addressed to the video relay device 1b is performed. The function of the video packet switching end determination unit 107 may be realized by software.

As described above, according to the ninth embodiment of the present invention, the video packet switching end judging means 1 for judging that the switching is completed at the switching stage of the video relay apparatus 1.
07 and the control means 105 for putting the video relay device 1b in the normal transfer operation transition mode until the destinations of all video packets are switched to the video relay device 1b, so that the destination information of all the video transmission devices 2a to 2f can be obtained. The video relay device 1b performs transfer by proxy until the change is completed, the packet transfer stop time due to switching of the video relay device 1 is suppressed, and the video receivers 3a and 3b cannot receive some video packets. The video disappears and the video can be continuously received.

(Tenth Embodiment) Next, a video relay apparatus according to a tenth embodiment of the present invention will be described with reference to FIGS. 1 to 5, video relay devices 1, 1a, 1b according to the present embodiment
Is configured to include a list of source or destination information of video packets to be transferred, calculate transfer rates described in the list and reception rates not included in the list, and control means 105 for detecting failure occurrence from the calculation results. To be done. Other than that, each component of the video relay apparatus 1 according to the present embodiment is the same as that of any one of the first to ninth embodiments, and the description thereof will be omitted. In the present embodiment,
The control means 105 is notified of the destination and source information for each packet received from the packet transfer means 102 of the video relay device 1 of the video relay device 1b in the standby mode. The control unit 105 holds a list of transmission source or transmission destination information of the video packets to be transferred, and calculates the total transfer rate of the transferred video packets on the list and the total reception rate of the video packets not on the list. Control means 105
Even if the transfer rate of the video packets on the list is reduced, if the packet reception rate other than the list is higher than the total transfer rate of the video packets on the list, the video relay device 1 is not a failure and the transmission line Judging that it is saturated,
A warning packet may be sent to encourage the reduction of the amount of transmission data.

As described above, according to the tenth embodiment of the present invention, even if the transfer rate is reduced due to the congestion of the transmission path, it is determined that the video relay apparatus 1 has failed and the video relay apparatus 1 is judged to have a fault. By providing the control means for transmitting the warning packet without performing the switching, the switching of the video relay device 1 is not performed.
Recovery can be promoted by reducing the amount of transmission data on the transmission path.

In the description of the first to tenth embodiments, the video relay device 1b in the standby mode performs the fault determination and the mode switching of the video relay device 1a in the other normal transfer modes. When all the video relay devices 1 are operated in the normal transfer mode to reduce the load of the video packet transfer, the failure determination is performed also in the normal transfer mode.
When a failure occurs in the video relay apparatus 1, the video packet transferred by the failed video relay apparatus 1 may be additionally transferred to the normally operating video relay apparatus 1.

[0063]

The video relay apparatus or relay method according to the present invention is configured as described above, and in particular, another apparatus based on the time interval of the packet transfer notification that the video packet is transferred or the video reception rate and the video transfer rate. When a failure occurs, the operation mode of the video repeater is switched and the standby video repeater is used when a failure is detected, so that packet transfer is automatically performed even if a failure occurs. Can be restored. Further, even if the packet transfer is not completely stopped due to the occurrence of a failure, the video relay device that transfers the video packet can be switched when the transfer rate is lowered, and the recovery can be performed so as to suppress the time when the video is interrupted.

Further, the video relay device or the relay method according to the present invention detects a failure occurrence in another video relay device based on the transfer rate of the video packet calculated by analyzing the video packet transferred by the other video relay device. By switching to the video relay device on standby, even if the packet transfer is not completely stopped due to the occurrence of a failure, the video relay device that transfers video packets is switched when the transfer rate drops, and the time at which video is interrupted is reduced. Restrained restoration can be performed.

Further, the video relay device or the relay method according to the present invention is such that the standby video relay is performed by detecting a buffer remaining amount warning notification from the video receiving device and the occurrence of a failure in another video relay device from the decrease of the video transfer rate. By switching to the device, the failure determination with higher accuracy is performed according to the actual buffer remaining amount of the video receiving device, and the video relay device that transfers the video packet is switched before the buffer remaining amount of the video receiving device is exhausted, It is possible to perform recovery while suppressing the time when the video is interrupted.

Further, in the video relay apparatus or relay method according to the present invention, the occurrence of a failure in another video relay apparatus is detected from the theoretical value of the remaining capacity calculated from the remaining capacity of the video data buffer of the video receiving apparatus and the decrease in the video transfer rate. By switching to the video relay device on standby, the error determination is performed more accurately by the estimated buffer remaining amount of the video receiving device, and the video packet is transferred before the buffer remaining amount of the video receiving device runs out. It is possible to switch the device to be used and perform recovery while suppressing the time when the image is interrupted.

Further, the video relay apparatus or relay method according to the present invention detects an alarm packet notifying that an abnormality has occurred, and when the alarm packet is detected, the fault occurrence determination criterion is strictly determined, so that it can be performed earlier than usual. The video relay device can be switched, and restoration can be performed while suppressing interruption of the video when an abnormality occurs.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a video relay device according to first to third embodiments of the present invention,

FIG. 2 is a block diagram showing a configuration of a video transmission network system using the video relay device according to the first to tenth embodiments of the present invention,

FIG. 3 is a block diagram showing a configuration of a video relay device according to fourth and fifth embodiments of the present invention,

FIG. 4 is a block diagram showing a configuration of a video relay device according to sixth to eighth embodiments of the present invention,

FIG. 5 is a block diagram showing a configuration of a video relay device according to a ninth embodiment of the present invention,

FIG. 6 is a block diagram showing a configuration of a conventional video transmission network system.

[Explanation of symbols]

1, 1a, 1b Video relay device 2a-2f Video transmitter 3a, 3b Video receiver 4a-4d hub 101a, 101b Packet input / output means 102 packet transfer means 104 Packet transfer notification input / output means 105 control means 106 buffer remaining amount calculating means 107 Video packet switching end determination means

Continued front page    (72) Inventor Masaaki Sato             3-1, Tsunashima-Higashi 4-chome, Kohoku-ku, Yokohama-shi, Kanagawa             Matsushita Communication Industry Co., Ltd. (72) Inventor Hideo Oi             3-1, Tsunashima-Higashi 4-chome, Kohoku-ku, Yokohama-shi, Kanagawa             Matsushita Communication Industry Co., Ltd. (72) Inventor Kenji Tokuda             1-3 1-3 Nishinen, Kanazawa, Ishikawa Prefecture Stock Association             Company Matsushita Communication Kanazawa Research Center F term (reference) 5B089 GB02 JB04 KA12 KC24 ME02                 5C022 CA08                 5C056 FA02 FA06 GA20 HA20                 5K030 GA12 HA08 HB02 JA11 MB01                       MB15 MD02

Claims (13)

[Claims] 1. A plurality of packet input / output means for inputting / outputting a video packet, and a packet transfer means for transferring the video packet input to the packet input / output means to another packet input / output means according to a destination thereof. Packet transfer notification input / output means for notifying the transfer of the video packet; and a control means for analyzing the content of the input video packet to determine a failure in the transfer of the video packet, and switching the operation mode when the failure occurs, The control means transfers the input video packet to the destination when the operation mode of the own device is the transfer mode, and when the operation mode of the own device is the standby mode, the failure occurrence is caused by the packet transfer notification received from the outside through the packet transfer notification input / output means. In the video, it has a function to switch the operation mode to the transfer mode when it is judged that a failure has occurred. Apparatus. 2. A plurality of packet input / output means for inputting / outputting a video packet, and a packet transfer means for transferring the video packet input to the packet input / output means to another packet input / output means according to a destination of the packet. The input video packet is analyzed by analyzing the content of the input video packet, determining a failure in the transfer of the video packet, and switching the operation mode when the failure occurs, and the control means inputs the input video packet when the operation mode is the transfer mode. To the destination. In the standby mode, the video packet transferred from the video packet source is received, the transfer rate of the received video packet is calculated, and the failure occurrence is determined. Is a video relay device having a function of switching an operation mode to a transfer mode. 3. The control means receives a video packet transferred from a video relay device operating in a normal transfer mode,
The transfer rate is calculated from the transfer data amount per unit time of the received video packet, and it is judged that a failure has occurred when the data amount per unit time of the video data set when encoding the video data is below the threshold value. The video relay apparatus according to claim 1, which has a function. 4. The control means receives a video packet transferred from a video relay device operating in a normal transfer mode via the packet input / output means, and transfers the received video packet from a transfer data amount per unit time. Calculate the rate,
Further, the control means receives a video packet addressed to a video relay device operating in the normal transfer mode, obtains a reception rate as a data amount per unit time, and determines the data amount per unit time set at the time of encoding the video data. 3. The video relay apparatus according to claim 1 or 2, further comprising a function of determining that the video relay apparatus operating in the normal mode has a failure when is less than or equal to a threshold value and the reception rate is greater than or equal to the threshold value. 5. A video receiving device, which is a destination of a video packet, receives a video packet addressed to a video relay device operating in a normal transfer mode, obtains a reception rate as a data amount per unit time, and receives the video packet. A buffer remaining amount warning packet is transmitted from the video receiving device when the remaining amount of video packets in the buffer of the video receiving device becomes less than or equal to a threshold, and the control means of the video relay device receives the buffer remaining amount warning packet. The video relay apparatus according to claim 1 or 2, further comprising a function of determining a failure when a buffer remaining amount warning packet generated when the reception rate of the received video packet is equal to or higher than a threshold value is received. 6. A data consumption amount obtained from a bit rate of video data by adding an initial storage capacity of a video packet and a received data capacity obtained from a data amount of a transfer packet in a video receiving device within a certain period. A buffer remaining amount calculating means for calculating a video data remaining amount estimation value of the video receiving device obtained by subtraction is provided, and the control means receives the video packet transferred from the video relay device operating in the normal transfer mode. , A transfer rate is calculated from the transfer data amount of a video packet per unit time, the packet transfer notification is not received even if it exceeds a specified time, and the estimated remaining amount of video data calculated by the buffer remaining amount calculation means and a failure determination When the estimated remaining amount of video data is less than the reference data amount for failure determination when comparing with the reference data amount, it is determined as a failure of the video relay device. Claim 1 or 2, characterized in that it has a function of switching the serial mode of operation of video relay device
The video relay device described. 7. The packet transfer means detects an alarm packet in the video packet transferred from the video relay apparatus operating in the normal transfer mode, and the control means is transferred from the video relay apparatus operating in the normal transfer mode. The transfer rate is calculated from the amount of data transferred per unit time of the video packet, and the error judgment period is stricter during the alarm state period from the reception of the alarm notification to the reception of the alarm cancellation notification. 4. The function of suppressing the possibility that the image display is interrupted by the video receiving device is provided by increasing the threshold of the transfer rate that becomes higher than that in the normal state to increase the probability of determining an abnormality.
6. The video relay device according to any one of 5 to 5. 8. When the control means determines that there is a failure in the transfer of a video packet received from the outside, the control means sets the proxy transfer mode for receiving and transferring the video packet from the source of the failed video packet, 8. The video relay apparatus according to claim 1, further comprising a function of receiving a video packet of the same destination as the video packet in which the failure has occurred and transferring the video packet by proxy during the proxy transfer mode. 9. The control means sets the video relay device to a proxy transfer mode for receiving and transferring a video packet transmitted from a transmission source of the video packet determined to have an external failure, and transmitting the video packet. A notification of correction of destination information is issued to the video transmission device, and when the video packets from all the video transmission devices are sent to the self video relay device, the self video relay device is shifted to the normal transfer mode. 9. The video relay apparatus according to claim 1, which has a function. 10. The control means has a list of video packets that pass the received video packets, measures the reception rate of packets that do not match the list, and reduces the transfer rate of the video packets existing in the list. Also, when the reception rate of the packets that do not match the list is high, it is not judged as a failure of the video relay device, but has a function of notifying a warning packet.
10. The video relay device according to any one of 9 to 9. 11. A video relay according to any one of claims 1 to 10, wherein a computer is made to function as a part or all of each means in the video relay apparatus according to any one of claims 1 to 10. A program for realizing some or all of the functions of the device. 12. A computer-readable recording medium in which the program according to claim 11 is recorded. 13. A plurality of video transmitting devices for packetizing and transmitting the captured video, a video receiving device for receiving and displaying the video packets, a network including the video transmitting device, and a network including the video receiving device. And a plurality of video relay devices for relaying the video relay device, the video relay device detects packet transfer of another video relay device to determine its failure, and when it is determined that there is a failure, both video relay devices are relayed. A video surveillance network system having a function of switching the operation modes of the above.