Switching method, rebroadcasting system, and rebroadcasting equipment

Abstract

To realize stable content reproduction in a reproduction device in a configuration capable of switching a rebroadcast device that retransmits content.SOLUTION: A switching method includes the steps of synchronizing a time between a rebroadcast device of an operational system and a rebroadcast device of a standby system, giving a switching start instruction from a control device to the rebroadcast device of the operational system and the rebroadcast device of the standby system, giving setting information indicating the settings for retransmission of the content in the rebroadcast device of the operational system to the rebroadcast device of the standby system, setting a switching timing through communication between the rebroadcast device of the operational system and the rebroadcast device of the standby system, and switching the retransmission of the content from the rebroadcast device of the operational system to the rebroadcast device of the standby system at the switching timing.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a switching method, a rebroadcasting system, and a rebroadcasting apparatus. Background Art

[0002] Conventionally, rebroadcasting systems that receive broadcast content and retransmit the received content have been developed.

[0003] For example, Patent Document 1 (Japanese Unexamined Patent Publication No. 2020-10199) discloses the following IP retransmission apparatus. Specifically, the IP retransmission apparatus is used in an IP retransmission system that retransmits digital broadcast signals of a plurality of channels received from an antenna to a plurality of receivers via an IP multicast network, extracts SI information from the digital broadcast signals, stores the SI information in a packet with an SI identification value added to a part of header information, and transmits the packet to the IP multicast network together with a broadcast stream or separately from the broadcast stream. Prior Art Literature Patent Literature

[0004] Patent Document 1 Japanese Unexamined Patent Publication No. 2020-10199 Summary of Invention Problem to be Solved by Invention

[0005] In a rebroadcasting system, a spare rebroadcasting apparatus is often provided in addition to the active rebroadcasting apparatus that performs content retransmission.

[0006] In this case, when retransmission by the operational retransmission equipment is stopped for maintenance or replacement, and the retransmission equipment responsible for retransmitting the content is switched from the operational retransmission equipment to a backup retransmission equipment, a technology is desired that enables the playback equipment to reproduce the content in good condition.

[0007] This disclosure was made to solve the above-mentioned problems, and its purpose is to provide a switching method, a retransmission system, and a retransmission device that can enable stable content playback in a playback device in a configuration in which a retransmission device for retransmitting content can be switched. [Means for solving the problem]

[0008] The switching method of the present disclosure is a switching method for switching the retransmission of content from an operational retransmission device to a standby retransmission device in a retransmission system comprising a plurality of retransmission devices for receiving and retransmitting the received content, and a control device, the method comprising: synchronizing the time between the operational retransmission device and the standby retransmission device; giving a switching start instruction from the control device to the operational retransmission device and the standby retransmission device; providing the standby retransmission device with setting information indicating the settings for retransmission of content in the operational retransmission device; setting a switching timing through communication between the operational retransmission device and the standby retransmission device; and switching the retransmission of content from the operational retransmission device to the standby retransmission device at the switching timing.

[0009] One aspect of this disclosure can be implemented not only as a switching method including such characteristic processing steps, but also as a program for causing a computer to perform such characteristic processing steps. Another aspect of this disclosure can be implemented as a semiconductor integrated circuit that implements part or all of a rebroadcasting device. [Effects of the Invention]

[0010] According to this disclosure, in a configuration in which a retransmission device that retransmits content can be switched, stable content playback can be achieved in the playback device. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a diagram showing the configuration of a rebroadcasting system according to the first embodiment of this disclosure. [Figure 2] Figure 2 shows the configuration of a rebroadcasting device according to the first embodiment of this disclosure. [Figure 3] Figure 3 shows an example of a switching sequence in a rebroadcasting system according to the first embodiment of this disclosure. [Figure 4] Figure 4 is a flowchart illustrating an example of the operation procedure when a control device according to the first embodiment of this disclosure transmits a switching start instruction. [Figure 5] Figure 5 is a flowchart illustrating an example of the operation procedure when a retransmission device according to the first embodiment of this disclosure switches to retransmission. [Figure 6] Figure 6 is a flowchart illustrating an example of the operation procedure when a rebroadcasting device according to the first embodiment of this disclosure performs a switching process. [Figure 7] Figure 7 is a flowchart illustrating an example of the operation procedure when a rebroadcasting device according to the first embodiment of this disclosure performs a switching process. [Figure 8] Figure 8 shows the configuration of a rebroadcasting system according to the second embodiment of this disclosure. [Figure 9] Figure 9 shows the configuration of a rebroadcasting device according to a second embodiment of the present disclosure. [Figure 10] Figure 10 shows the configuration of a rebroadcasting system according to the third embodiment of this disclosure. [Figure 11] Figure 11 shows the configuration of a rebroadcasting device according to a third embodiment of the present disclosure. [Figure 12]FIG. 12 is a diagram showing a configuration of a rebroadcasting system according to a fourth embodiment of the present disclosure. [Figure 13] FIG. 13 is a diagram showing a configuration of a rebroadcasting apparatus according to the fourth embodiment of the present disclosure. DETAILED DESCRIPTION OF EMBODIMENTS

[0012] First, the contents of the embodiments of the present disclosure will be listed and described.

[0013] (1) A switching method according to an embodiment of the present disclosure is a switching method for switching retransmission of said content from an active rebroadcasting apparatus to a standby rebroadcasting apparatus in a rebroadcasting system including a plurality of rebroadcasting apparatuses that receive content and retransmit the received said content, and a control apparatus, the method comprising: performing time synchronization between the active rebroadcasting apparatus and the standby rebroadcasting apparatus; providing a switching start instruction from the control apparatus to the active rebroadcasting apparatus and the standby rebroadcasting apparatus; providing setting information indicating setting contents of retransmission of said content in the active rebroadcasting apparatus to the standby rebroadcasting apparatus; setting switching timing through communication between the active rebroadcasting apparatus and the standby rebroadcasting apparatus; and switching retransmission of said content from the active rebroadcasting apparatus to the standby rebroadcasting apparatus at said switching timing.

[0014] In this way, by the method of setting switching timing through communication between the active rebroadcasting apparatus and the standby rebroadcasting apparatus, and switching retransmission of content from the active rebroadcasting apparatus to the standby rebroadcasting apparatus at the switching timing, compared with a method of setting switching timing through communication between other apparatuses and the active and standby rebroadcasting apparatuses and switching retransmission of content, the setting of switching timing and the switching of content retransmission at said switching timing can be performed more reliably. Therefore, in a configuration in which the rebroadcasting apparatus that performs content retransmission can be switched, stable content reproduction in a reproducing apparatus can be realized.

[0015] (2) In (1) above, the switching method may further comprise: a step of defining the plurality of active rebroadcasting devices to be switched as an active set; and a step of defining the plurality of standby rebroadcasting devices to be switched as a standby set, and the method may be a method for switching retransmission of said content from said active rebroadcasting device to said standby rebroadcasting device for each pair of said active rebroadcasting device included in said active set and said standby rebroadcasting device included in said standby set.

[0016] According to such a method, for example, planned maintenance and replacement of a plurality of active rebroadcasting devices respectively corresponding to a plurality of channels can be performed.

[0017] (3) In (2) above, the active set may be included in one sub-chassis, and the standby set may be included in another sub-chassis different from said sub-chassis; after the step preceding the step of switching retransmission of said content is performed for all said pairs in said active set and said standby set, the step of switching retransmission of said content may be performed for all said pairs in said active set and said standby set.

[0018] According to such a method, when switching content retransmission among a plurality of pairs of active rebroadcasting devices and standby rebroadcasting devices, switching of content retransmission for each pair can be collectively performed in units of sub-chassis.

[0019] (4) In any one of (1) to (3) above, the switching method may further comprise a step of performing a connection establishment process for establishing a communication connection between said active rebroadcasting device and said standby rebroadcasting device; in the step of setting said switching timing, said switching timing may be set through communication using said communication connection, and the switching method may further comprise a step of performing said connection establishment process again when setting of said switching timing fails.

[0020] This method allows for more reliable setting of the switching timing, even in the event of communication errors or other issues.

[0021] (5) The retransmission system according to the embodiment of the present disclosure is a retransmission system for retransmitting content, comprising a plurality of retransmission devices for receiving and retransmitting the received content, and a control device, wherein the operational retransmission device and the standby retransmission device perform time synchronization, the control device transmits a switching start instruction to the operational retransmission device and the standby retransmission device to switch the retransmission of the content from the operational retransmission device to the standby retransmission device, the operational retransmission device transmits setting information indicating the setting content for retransmission of the content to the standby retransmission device, the operational retransmission device and the standby retransmission device set a switching timing through communication between the operational retransmission device and the standby retransmission device, the operational retransmission device stops transmitting the content at the switching timing, and the standby retransmission device starts transmitting the content at the switching timing.

[0022] In this configuration, the switching timing is set by communication between the operational retransmission device and the standby retransmission device, and at that switching timing, the retransmission of content is switched from the operational retransmission device to the standby retransmission device. This configuration allows for more reliable setting of the switching timing and switching of content retransmission at that switching timing compared to a configuration where the switching timing is set by communication between other devices and the operational and standby retransmission devices. Therefore, in a configuration where the retransmission device performing content retransmission can be switched, stable content playback in the playback device can be achieved.

[0023] (6) The retransmission device according to the embodiment of the present disclosure is a retransmission device in a retransmission system for retransmitting content, comprising: a content receiving unit for receiving the content; a content transmitting unit for transmitting the content received by the content receiving unit; an instruction receiving unit for receiving a switching start instruction for switching the execution of retransmission of the content between the retransmission device and other retransmission devices; a setting unit for setting a switching timing which is the timing at which the start and stop of the transmission of the content by the content transmitting unit should be switched by communicating with the other retransmission device indicated by the switching start instruction received by the instruction receiving unit; and a switching unit for switching the start and stop of the transmission of the content by the content transmitting unit at the switching timing set by the setting unit.

[0024] Thus, by setting the switching timing through communication with other retransmission devices and switching the start and stop of content transmission at that switching timing, it is possible to set the switching timing and switch the start and stop of content transmission at that switching timing more reliably compared to a configuration in which the switching timing is set through communication with devices other than the retransmission device and the start and stop of content transmission is switched at that switching timing. Therefore, in a configuration in which the retransmission device that retransmits content can be switched, stable content playback on the playback device can be achieved.

[0025] Embodiments of this disclosure will be described below with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and their descriptions will not be repeated. Furthermore, at least some of the embodiments described below may be combined in any way.

[0026] <First Embodiment> [Configuration and Basic Operation] Figure 1 is a diagram showing the configuration of a retransmission system according to a first embodiment of the present disclosure. Referring to Figure 1, the retransmission system 301 comprises antennas 81A and 81B, distributors 91A and 91B, a plurality of retransmission devices 101, interface units 111A and 111B, a control device 201, and switch devices 121A, 121B, 131, and 211. Hereinafter, each of the distributors 91A and 91B will also be referred to as distributor 91, and each of the switch devices 121A and 121B will also be referred to as switch device 121. The retransmission system 301 receives a broadcast signal containing content and retransmits the content in an IP packet.

[0027] As an example, the rebroadcasting system 301 comprises N rebroadcasting devices 101A, which are the operational rebroadcasting devices 101, and M rebroadcasting devices 101B, which are the standby rebroadcasting devices 101. N and M are integers greater than or equal to 1. N and M may be the same value or may be different values. The rebroadcasting devices 101B are spare rebroadcasting devices 101 for backup of the rebroadcasting devices 101A. Hereafter, the rebroadcasting system 301 will be assumed to comprise 12 rebroadcasting devices 101A and 12 rebroadcasting devices 101B.

[0028] Each retransmission device 101A is connected to a switch device 121A via a LAN (Local Area Network) cable. Each retransmission device 101B is connected to a switch device 121B via a LAN cable. Switch device 121 is connected to a switch device 131 via a LAN cable. The LAN cables connecting the retransmission devices 101 and the switch device 121, and the LAN cables connecting the switch device 121 and the switch device 131, constitute, for example, a dedicated line for a cable television station.

[0029] For example, the retransmission device 101A and interface unit 111A are mounted on a sub-chassis SA and installed in the cable television station building. The interface unit 111A is communicated with each retransmission device 101A.

[0030] Furthermore, for example, the retransmission device 101B and interface unit 111B are mounted on sub-chassis SB and are located in a different station building from the retransmission device 101A and interface unit 111A. Interface unit 111B is communicated with each retransmission device 101B.

[0031] The control device 201 is connected to interface units 111A and 111B via a switch device 211. For example, the control device 201 is connected to interface units 111A and 111B via a LAN cable that is physically different from the LAN cable connecting the rebroadcasting device 101A and the switch device 121A, and also different from the LAN cable connecting the rebroadcasting device 101B and the switch device 121B. The control device 201 controls and monitors each rebroadcasting device 101.

[0032] After each retransmission device 101 in the retransmission system 301 is started up, the control device 201 transmits setting information C1 regarding the retransmission of content to the operational retransmission device 101A via the switch device 211 and interface unit 111A, and transmits a standby instruction S1 indicating that the device should wait for the retransmission of content to be resumed to the standby retransmission device 101B via the switch device 211 and interface unit 111B.

[0033] Distributors 91A and 91B each receive RF (Radio Frequency) band broadcast signals containing content from terrestrial digital broadcasting, BS digital broadcasting, or advanced BS digital broadcasting via antennas 81A and 81B, respectively. This content includes, for example, audio information, video information, PSI (Program Specific Information) information, SI (Service Information) information, and subtitle information. Distributor 91A distributes the received broadcast signals to each retransmission device 101A. Distributor 91B distributes the received broadcast signals to each retransmission device 101B.

[0034] The rebroadcasting device 101 receives the content. More specifically, the rebroadcasting devices 101A and 101B receive the broadcast signal containing the content from the distributors 91A and 91B, respectively.

[0035] Rebroadcasting device 101B does not rebroadcast content in its initial state. On the other hand, rebroadcasting device 101A does rebroadcast content in its initial state.

[0036] More specifically, each of the 12 rebroadcasting devices 101A is assigned, for example, a different channel. The rebroadcasting device 101A acquires content belonging to its assigned channel from the broadcast signal according to the configuration information C1 received from the control device 201, generates an IP packet containing the acquired content, and multicasts the generated IP packet to the STB (Set Top Box) 151 at the subscriber's home via the switch devices 121A, 131 and the IP network 141. In the IP network 141, the IP packets are transmitted according to the IP protocol.

[0037] The STB151 acquires content from IP packets received from the rebroadcasting device 101 via the IP network 141, and plays the acquired content on a display device (not shown).

[0038] In the retransmission system 301, retransmission by retransmission device 101A may be stopped for maintenance or replacement of retransmission device 101A, and the retransmission device 101 that performs content retransmission may be switched from retransmission device 101A to retransmission device 101B.

[0039] For example, in the retransmission system 301, for maintenance or replacement of the retransmission device 101A, the retransmission of 12 different content items belonging to 12 different channels is switched from the 12 retransmission devices 101A in sub-chassis SA to the 12 retransmission devices 101B in sub-chassis SB. The switching of the retransmission devices 101 that perform the content retransmission is performed, for example, at night.

[0040] (assignment) When switching the retransmission device 101, which performs content retransmission, from retransmission device 101A to retransmission device 101B, a technology is desired that enables the STB 151 to play the content in good condition.

[0041] More specifically, when switching the retransmission device 101, which performs content retransmission, from retransmission device 101A to retransmission device 101B, a possible configuration is considered in which the control device 201 determines the switching timing and notifies the determined switching timing to the retransmission devices 101A and 101B, respectively, via the switch device 211 and interface units 111A and 111B.

[0042] However, in this configuration, if, for example, a communication error between the control device 201 and the retransmission device 101B prevents the control device 201 from notifying the retransmission device 101B of the switching timing, the retransmission of content by the retransmission device 101A will stop, while the retransmission of content by the retransmission device 101B will not start. In this case, the STB 151 may not be able to play the content properly.

[0043] In contrast, the rebroadcasting system 301 according to the first embodiment of this disclosure solves the above problem through the following configuration and operation.

[0044] (Rebroadcasting device) Figure 2 is a diagram showing the configuration of a rebroadcasting device according to a first embodiment of the present disclosure. Referring to Figure 2, the rebroadcasting device 101 comprises a tuner 11, a packet processing unit 12, an IP transmission / reception unit 13, a control unit 14, a counter 15, and a storage unit 16. The tuner 11 is an example of a content receiving unit. The IP transmission / reception unit 13 is an example of a content transmission unit. The control unit 14 is an example of an instruction receiving unit, an example of a setting unit, and an example of a switching unit. Some or all of the tuner 11, packet processing unit 12, IP transmission / reception unit 13, and control unit 14 are implemented by a processing circuit (Circuitry) including, for example, one or more processors. The storage unit 16 is, for example, a non-volatile memory included in the above processing circuit.

[0045] Counter 15 receives a clock signal from an oscillator (not shown) and updates the count value according to the timing of the received clock signal.

[0046] The tuner 11 receives a broadcast signal containing content from the distributor 91. The tuner 11 also receives a demodulation start instruction from the control unit 14. In accordance with the demodulation start instruction received from the control unit 14, the tuner 11 performs demodulation processing on the broadcast signal received from the distributor 91, thereby generating a stream containing content belonging to the channel assigned to the rebroadcasting device 101. The tuner 11 outputs the generated stream to the packet processing unit 12.

[0047] The packet processing unit 12 generates multiple TS (Transport Stream) packets, each containing data divided from the stream received from the tuner 11, with a data length of 188 bytes. Each time the packet processing unit 12 generates a TS packet, it obtains the count value of the counter 15, and generates a TTS (Time-stamped TS) packet with the count value added as a timestamp to the generated TS packet, which is then output to the IP transceiver 13.

[0048] The IP transceiver 13 transmits the content received by the tuner 11. For example, the IP transceiver 13 sends an IP flow, which is a series of IP packets containing the content, to the switch device 121. More specifically, the IP transceiver 13 generates an IP packet containing one or more TTS packets received from the packet processing unit 12, includes the generated IP packet in a frame, and sends it to the switch device 121.

[0049] The tuner 11 can switch between a generation-on state, which generates a stream containing content, and a generation-off state, which does not generate a stream. For example, the tuner 11 is set to the generation-off state when the rebroadcasting device 101 is started up.

[0050] The IP transceiver 13 can switch between a transmit-on state, which transmits IP flows, and a transmit-off state, which does not transmit IP flows. For example, the IP transceiver 13 is set to the transmit-off state when the rebroadcasting device 101 is started up.

[0051] (Initial settings) The control unit 14 in the rebroadcasting device 101B receives a standby instruction S1 from the control device 201 and maintains the tuner 11 in the generation-off state and the IP transceiver 13 in the transmission-off state according to the received standby instruction S1.

[0052] The control unit 14 in the rebroadcasting device 101A receives configuration information C1 from the control device 201. The configuration information C1 indicates the frequency F1 of the broadcast signal to be demodulated by the tuner 11 and the content transmission configuration information. For example, the transmission configuration information includes the destination IP address, destination port number, and VLAN tag. The control unit 14 stores the received configuration information C1 in the storage unit 16.

[0053] In the rebroadcasting device 101A, the control unit 14 switches the tuner 11 to the generation ON state and the IP transceiver 13 to the transmission ON state according to the setting information C1 received from the control device 201. More specifically, the control unit 14 outputs a demodulation start instruction including the setting information C1 to the tuner 11 and a transmission start instruction including the setting information C1 to the IP transceiver 13.

[0054] When the tuner 11 receives a demodulation start instruction from the control unit 14, it starts generating and outputting a stream containing content according to the setting information C1 included in the received demodulation start instruction. More specifically, the tuner 11 starts generating and outputting a stream containing content by performing demodulation processing on the broadcast signal with frequency F1 indicated by the setting information C1 from the broadcast signal received from the distributor 91.

[0055] When the IP transceiver 13 receives a transmission start instruction from the control unit 14, it starts transmitting an IP packet containing content according to the configuration information C1 included in the received transmission start instruction. More specifically, the IP transceiver 13 generates an IP packet in which the payload contains content and the header contains the destination IP address and destination port number indicated by the configuration information C1, and transmits the generated IP packet to the switch device 121 in a frame to which the VLAN tag indicated by the configuration information C1 is attached.

[0056] (Instruction to start switching) For example, the control device 201 creates a switching plan for content retransmission in the retransmission device 101A and the retransmission device 101B.

[0057] More specifically, the control device 201 determines which of the 12 retransmission devices 101A should stop retransmitting content and which retransmission device 101B should start retransmitting content in place of the aforementioned retransmission device 101A. Hereinafter, the retransmission device 101A that should stop retransmitting content will also be referred to as the "original retransmission device 101A," and the retransmission device 101B that should start retransmitting content will also be referred to as the "destination retransmission device 101B."

[0058] The control device 201 functions as an NTP (Network Time Protocol) server and sends NTP synchronization instructions, including NTP information indicating the current time, to the source rebroadcasting device 101A and the destination rebroadcasting device 101B via the switch device 211 and interface units 111A and 111B.

[0059] The rebroadcasting devices 101A and 101B receive an NTP synchronization instruction from the control device 201 and synchronize their time according to the received NTP synchronization instruction. More specifically, the control unit 14 in the rebroadcasting devices 101A and 101B updates the count value of the counter 15 based on the NTP information included in the NTP synchronization instruction received from the control device 201. As a result, the rebroadcasting devices 101A and 101B synchronize with each other. When the control unit 14 has finished updating the count value, it sends a synchronization completion notification to the control device 201 via the interface unit 111 and the switch device 211 as a response to the NTP synchronization instruction.

[0060] The control device 201 sends a switching start instruction to the rebroadcasting devices 101A and 101B, indicating that it is switching the execution of content retransmission from the original rebroadcasting device 101A to the destination rebroadcasting device 101B. More specifically, when the control device 201 receives a synchronization completion notification from the rebroadcasting devices 101A and 101B, it includes the switching start instruction in an IP packet and sends it to the rebroadcasting devices 101A and 101B via the switch device 211 and interface unit 111.

[0061] When the rebroadcasting devices 101A and 101B receive a switching start instruction from the control device 201, they send a switching start notification to the control device 201 via the interface unit 111 and the switch device 211 as a response to the switching start instruction. The rebroadcasting devices 101A and 101B also execute the switching process in accordance with the switching start instruction received from the control device 201.

[0062] (Switching process) (1) Connection establishment process In the rebroadcasting device 101A, the control unit 14 receives a switching start instruction from the control device 201 via the switch device 211 and interface unit 111A. In the rebroadcasting device 101B, the control unit 14 receives a switching start instruction from the control device 201 via the switch device 211 and interface unit 111B.

[0063] The control unit 14 in the rebroadcasting device 101A and the control unit 14 in the rebroadcasting device 101B establish a communication connection and communicate using the established communication connection. For example, the control unit 14 in the rebroadcasting device 101A and the control unit 14 in the rebroadcasting device 101B establish a communication connection that follows TCP (Transmission Control Protocol). Hereinafter, a communication connection that follows TCP will also be referred to as a "TCP connection".

[0064] More specifically, the control unit 14 in the rebroadcasting device 101A is a TCP server and waits for a SYN packet from the rebroadcasting device 101B indicated by the switching start instruction. A SYN packet is a TCP packet with the SYN flag set to ON in the TCP header, and is a connection request from a TCP client.

[0065] The control unit 14 in the rebroadcasting device 101B is a TCP client and transmits SYN packets to the rebroadcasting device 101A indicated by the switching start instruction via the IP transceiver unit 13 and the switch devices 121B, 131, and 121A.

[0066] The control unit 14 in the rebroadcasting device 101A receives a SYN packet from the rebroadcasting device 101B via the IP transceiver unit 13 and transmits a SYN / ACK packet to the rebroadcasting device 101B via the IP transceiver unit 13 and the switch devices 121A, 131, and 121B. A SYN packet is a TCP packet in which the SYN flag and ACK flag in the TCP header are set to ON.

[0067] The control unit 14 in the rebroadcasting device 101B receives a SYN / ACK packet from the rebroadcasting device 101A via the IP transceiver unit 13 and sends an ACK packet to the rebroadcasting device 101A via the IP transceiver unit 13 and the switch devices 121B, 131, and 121A. The ACK packet is a TCP packet with the ACK flag in the TCP header set to ON. This establishes a TCP connection between the control unit 14 in the rebroadcasting device 101A and the control unit 14 in the rebroadcasting device 101B.

[0068] (2) Sending configuration information When the control unit 14 in the rebroadcasting device 101B establishes a TCP connection with the control unit 14 in the rebroadcasting device 101A, it uses the TCP connection to send a configuration information request in an IP packet to the rebroadcasting device 101A via the IP transceiver 13 and the switch devices 121B, 131, and 121A.

[0069] The rebroadcasting device 101A transmits the configuration information C1 to the rebroadcasting device 101B. More specifically, when the control unit 14 of the rebroadcasting device 101A receives a configuration information request from the rebroadcasting device 101B, it obtains the configuration information C1 from the storage unit 16. Then, as a response to the configuration information request, the control unit 14 uses a TCP connection to include the configuration information C1 in an IP packet and transmits it to the rebroadcasting device 101B via the IP transceiver unit 13 and the switch devices 121A, 131, and 121B. In other words, the control unit 14 transmits the configuration information C1 to the rebroadcasting device 101B using the physical communication path for content transmission.

[0070] The control unit 14 in the rebroadcasting device 101B receives setting information from the rebroadcasting device 101A and stores the received setting information C1 in the storage unit 16. The control unit 14 also switches the tuner 11 to the generation ON state. More specifically, the control unit 14 outputs a demodulation start instruction, including the setting information C1, to the tuner 11 in the rebroadcasting device 101B.

[0071] The tuner 11 receives a demodulation start instruction from the control unit 14 and starts generating and outputting a stream containing content according to the setting information C1 included in the received demodulation start instruction.

[0072] As mentioned above, in the rebroadcasting system 301, the rebroadcasting devices 101A and 101B are installed in different buildings. Therefore, compared to a system where the rebroadcasting devices 101A and 101B are installed in the same building, the communication path between the rebroadcasting devices 101A and 101B is often more vulnerable. In contrast, by using a TCP connection for communication between the rebroadcasting devices 101A and 101B, the transmission of configuration information requests and configuration information C1 between the rebroadcasting devices 101A and 101B can be made more reliable.

[0073] (3) Setting the switching timing The control unit 14 in the rebroadcasting device 101A communicates with the rebroadcasting device 101B to set the switching timing, which is the timing at which the IP transceiver 13 should switch between starting and stopping content transmission. The control unit 14 in the rebroadcasting device 101B communicates with the rebroadcasting device 101A to set the switching timing.

[0074] More specifically, the control unit 14 in the rebroadcasting device 101B determines the switching timing. For example, the control unit 14 determines the switching timing to be specific to the channel assigned to the rebroadcasting device 101A. As an example, the control unit 14 determines the switching timing to be the timing at which the program on that channel changes. Alternatively, the control unit 14 may obtain the count value of the counter 15 when it receives the setting information C1 from the rebroadcasting device 101B, and determine the switching timing to be the obtained count value plus a predetermined value.

[0075] The control unit 14 stores timing information indicating the determined switching timing in the storage unit 16. The control unit 14 also transmits the timing information, including it in an IP packet, to the rebroadcasting device 101A via the IP transceiver unit 13 and the switch devices 121B, 131, and 121A using a TCP connection. In other words, the control unit 14 transmits the timing information to the rebroadcasting device 101A using the physical communication path for content transmission.

[0076] The control unit 14 in the rebroadcasting device 101A receives timing information from the rebroadcasting device 101B and stores the received timing information in the storage unit 16. In response to the timing information, the control unit 14 sends a configuration completion notification, including it in an IP packet, to the rebroadcasting device 101B via the IP transceiver unit 13 and the switch devices 121A, 131, and 121B using a TCP connection.

[0077] As mentioned above, in the rebroadcasting system 301, the rebroadcasting devices 101A and 101B are installed in different buildings. Therefore, compared to a system where the rebroadcasting devices 101A and 101B are installed in the same building, the communication path between the rebroadcasting devices 101A and 101B is often more vulnerable. In contrast, by using a TCP connection for communication between the rebroadcasting devices 101A and 101B, the transmission of timing information and setting completion notifications between the rebroadcasting devices 101A and 101B can be made more reliable.

[0078] In the rebroadcasting devices 101A and 101B, the control unit 14 switches the start and stop of content transmission by the IP transceiver unit 13 at the switching timing. Specifically, rebroadcasting device 101A stops content transmission at the switching timing, and rebroadcasting device 101B starts content transmission at the switching timing.

[0079] More specifically, when the control unit 14 in the rebroadcasting device 101B receives a setting completion notification from the rebroadcasting device 101A, it waits for the switching timing indicated by the timing information to arrive, and at the switching timing, switches the IP transceiver 13 to the transmit ON state. Specifically, the control unit 14 outputs a transmission start instruction including the setting information C1 to the IP transceiver 13.

[0080] In the rebroadcasting device 101B, the IP transmission / reception unit 13 receives a transmission start instruction from the control unit 14 and starts transmitting an IP packet containing content according to the configuration information C1 included in the received transmission start instruction.

[0081] The control unit 14 in the rebroadcasting device 101A waits for the arrival of the switching timing indicated by the timing information, and switches the IP transceiver 13 to the transmission off state at the switching timing. Specifically, when the switching timing arrives, the control unit 14 outputs a transmission stop instruction to the IP transceiver 13.

[0082] In the rebroadcasting device 101B, the IP transmission / reception unit 13 receives a transmission stop instruction from the control unit 14 and stops transmitting the IP packet containing the content.

[0083] In the rebroadcasting device 101A, if the control unit 14 stops transmitting content at the switching timing, it sends a switching completion notification to the control device 201 via the interface unit 111A and the switch device 211. In the rebroadcasting device 101B, if the control unit 14 starts transmitting content at the switching timing, it sends a switching completion notification to the control device 201 via the interface unit 111B and the switch device 211.

[0084] While the control unit 14 in the rebroadcasting device 101A and the control unit 14 in the rebroadcasting device 101B are configured to establish a TCP connection by exchanging TCP packets via the IP transmission / reception unit 13 and the switch devices 121 and 131, this configuration is not limited to that. The control unit 14 in the rebroadcasting device 101A and the control unit 14 in the rebroadcasting device 101B may also be configured to establish a TCP connection by exchanging TCP packets via the interface unit 111 and the switch device 211.

[0085] In this case, the control unit 14 in the rebroadcasting device 101B transmits the configuration information request and timing information to the rebroadcasting device 101A via the interface unit 111 and the switch device 211 using a TCP connection. That is, the control unit 14 in the rebroadcasting device 101B transmits the configuration information request and timing information to the rebroadcasting device 101A using a physical communication path for control. Also, the control unit 14 in the rebroadcasting device 101A transmits the configuration information C1 and the configuration completion notification to the rebroadcasting device 101B via the interface unit 111 and the switch device 211 using a TCP connection. That is, the control unit 14 in the rebroadcasting device 101A transmits the configuration information C1 and the configuration completion notification to the rebroadcasting device 101B using a physical communication path for control.

[0086] [Operation Flow] Figure 3 shows an example of a switching sequence in a rebroadcasting system according to the first embodiment of this disclosure.

[0087] Referring to Figure 3, first, the control device 201 creates a switching plan that includes the source rebroadcasting device 101A and the destination rebroadcasting device 101B (step S11).

[0088] Next, in the switching method of the rebroadcasting system 301, time synchronization is performed between the rebroadcasting device 101A that is the source of the switch and the rebroadcasting device 101B that is the destination. More specifically, the control device 201 sends an NTP synchronization instruction including NTP information to the rebroadcasting device 101A that is the source of the switch (step S12).

[0089] Next, the rebroadcasting device 101A updates the count value of the counter 15 based on the NTP information included in the NTP synchronization instruction received from the control device 201 (step S13).

[0090] Next, the rebroadcasting device 101A sends a synchronization completion notification to the control device 201 in response to the NTP synchronization instruction (step S14).

[0091] Next, the control device 201 sends an NTP synchronization instruction, including NTP information, to the rebroadcasting device 101B that is the target of the switch (step S15).

[0092] Next, the rebroadcasting device 101B updates the count value of counter 15 based on the NTP information included in the NTP synchronization instruction received from control device 201 (step S16).

[0093] Next, the rebroadcasting device 101B sends a synchronization completion notification to the control device 201 in response to the NTP synchronization instruction (step S17).

[0094] Next, in the switching method for the rebroadcasting system 301, a switching start instruction is given to the rebroadcasting devices 101A and 101B. More specifically, the control device 201 transmits the switching start instruction to the rebroadcasting device 101A (step S18).

[0095] Next, the rebroadcasting device 101A sends a switching start notification to the control device 201 in response to the switching start instruction (step S19).

[0096] Next, the control device 201 transmits a switching start instruction to the rebroadcasting device 101B (step S20).

[0097] Next, the rebroadcasting device 101B sends a switching start notification to the control device 201 in response to the switching start instruction (step S21).

[0098] Next, in the switching method of the rebroadcasting system 301, a connection establishment process is performed to establish a communication connection between the rebroadcasting device 101A and the rebroadcasting device 101B. More specifically, the rebroadcasting device 101B, as a TCP client, sends a SYN packet, which is a connection request to the TCP server, to the rebroadcasting device 101A indicated by the switching start instruction (step S22).

[0099] Next, the rebroadcasting device 101A, acting as a TCP server, sends a SYN / ACK packet to the rebroadcasting device 101B (step S23).

[0100] Next, the rebroadcasting device 101B sends an ACK packet to the rebroadcasting device 101A (step S24). This establishes a TCP connection between the rebroadcasting device 101A and the rebroadcasting device 101B.

[0101] Next, in the switching method in the rebroadcasting system 301, the setting information C1 from the rebroadcasting device 101A is provided to the rebroadcasting device 101B. More specifically, the rebroadcasting device 101B sends a setting information request to the rebroadcasting device 101A using a TCP connection (step S25).

[0102] Next, the rebroadcasting device 101A sends the configuration information C1 to the rebroadcasting device 101B using a TCP connection as a response to the configuration information request (step S26).

[0103] Next, in the switching method for the rebroadcasting system 301, the switching timing is set by communication using a TCP connection between the rebroadcasting device 101A and the rebroadcasting device 101B. More specifically, the rebroadcasting device 101B determines the switching timing and transmits timing information indicating the determined switching timing to the rebroadcasting device 101A using the TCP connection (step S27).

[0104] Next, the rebroadcasting device 101A sends a configuration completion notification to the rebroadcasting device 101B using a TCP connection as a response to the timing information (step S28).

[0105] Next, in the switching method of the rebroadcasting system 301, at the switching timing, the retransmission of content is switched from rebroadcasting device 101A to rebroadcasting device 101B. More specifically, rebroadcasting device 101A waits for the arrival of the switching timing and stops transmitting content at the switching timing (step S29).

[0106] Furthermore, the rebroadcasting device 101B waits for the switching timing to arrive and starts transmitting content at the switching timing (step S30).

[0107] Next, the rebroadcasting device 101A sends a notification of completion of switching to the control device 201 (step S31).

[0108] Furthermore, the rebroadcasting device 101B sends a notification of completion of the switchover to the control device 201 (step S32).

[0109] For example, in the switching method of the rebroadcasting system 301, if the setting of the switching timing fails, the connection establishment process is performed again. More specifically, if the rebroadcasting device 101B does not receive a setting completion notification from the rebroadcasting device 101A within a predetermined time after sending the timing information, it times out and interrupts the switching process. Then, the rebroadcasting device 101B sends a SYN packet again (step S22).

[0110] Similarly, if the rebroadcasting device 101B does not receive the configuration information C1 from the rebroadcasting device 101A within a predetermined time after sending the configuration information request, it will time out and interrupt the switching process. The rebroadcasting device 101B will then send a SYN packet again (step S22). If the rebroadcasting device 101B interrupts the switching process, it may send an error notification to the control device 201 instead of sending a SYN packet. If the control device 201 receives the error notification, it may, for example, create a switching plan again (step S11).

[0111] Furthermore, for example, if the rebroadcasting device 101A does not receive an ACK packet from the rebroadcasting device 101B within a predetermined time after sending a SYN / ACK packet, it times out and interrupts the switching process. The rebroadcasting device 101A then waits for another SYN packet to arrive. If the rebroadcasting device 101A interrupts the switching process, it may send an error notification to the control device 201 instead of waiting for a SYN packet to arrive. If the control device 201 receives the error notification, it may, for example, create a switching plan again (step S11).

[0112] Furthermore, for example, if the control device 201 does not receive a synchronization completion notification from the rebroadcasting devices 101A and 101B within a predetermined time after sending an NTP synchronization instruction, if it does not receive a switch-start notification from the rebroadcasting devices 101A and 101B within a predetermined time after sending a switch-start instruction, or if it does not receive a switch-completion notification from the rebroadcasting devices 101A and 101B within a predetermined time after receiving a switch-start notification, the control device 201 times out. Then, the control device 201 creates a switch-out plan again (step S11).

[0113] In the retransmission system 301, when switching the retransmission of content from multiple retransmission devices 101A to multiple retransmission devices 101B, the retransmission switching is carried out in a planned manner. For example, in step S11, the control device 201 designates the multiple retransmission devices 101A to be switched as the operational set and the multiple retransmission devices 101B to be switched as the standby set. More specifically, if, for example, a power outage is planned for the entire station building, the control device 201 designates the 12 retransmission devices 101 contained in sub-chassis SA within the station building as the operational set, and the 12 retransmission devices 101B contained in sub-chassis SB in another station building, which are the counterparts to the 12 retransmission devices 101A, as the standby set.

[0114] The control device 201 may determine the standby system set to be switched over to, depending on the number of rebroadcasting devices 101A included in the operational system set. For example, suppose a certain station building X has chassis rack Xp with p units of rebroadcasting devices 101A installed, and chassis rack Xq with q units of rebroadcasting devices 101A installed. If only chassis rack Xp of chassis racks Xp and Xq experiences a power outage due to power supply replacement, the control device 201 will determine the p units of rebroadcasting devices 101A installed in chassis rack Xp as the operational system set. The control device 201 will then determine the p units of rebroadcasting devices 101B installed in chassis rack Yp in another station building Y, which are the counterparts to the p units of rebroadcasting devices 101A designated as the operational system set, as the standby system set. In this case, the rebroadcasting devices 101B in station Y, which are smaller in scale than station X with chassis racks Xp and Xq, can be designated as the standby system set.

[0115] After defining the operational set and the standby set, the process from step S12 to step S32 above is executed for each pair of retransmission devices, namely the retransmission device 101A included in the operational set and the retransmission device 101B included in the standby set, thereby switching the retransmission of content from the retransmission device 101A to the retransmission device 101B.

[0116] For example, in the switching method for the retransmission system 301, the steps preceding the step of switching the retransmission of content are performed for all pairs of retransmission devices 101A and 101B, and then the step of switching the retransmission of content is performed for all pairs of retransmission devices 101A and 101B. That is, when switching the retransmission of content from multiple retransmission devices 101A to multiple retransmission devices 101B, the switching step is executed for all pairs of retransmission devices 101A and 101B that are subject to switching, after the steps up to the moment immediately preceding the switch have been completed.

[0117] More specifically, after performing the processes from steps S12 to S28 for each pair of rebroadcasting devices 101A and 101B, the processes from steps S29 to S32 are performed for each pair of rebroadcasting devices 101A and 101B. This prevents the switching from the operational set to the standby set from stopping midway due to malfunctions such as communication interruptions, and allows the switching from the operational set to the standby set to be performed collectively, for example, on a sub-chassis basis.

[0118] Furthermore, for example, in the switching method in the rebroadcasting system 301, the switching of content retransmission from multiple rebroadcasting devices 101A to multiple rebroadcasting devices 101B is performed sequentially for each channel. More specifically, in the switching method in the rebroadcasting system 301, the processes from step S11 to step S32 described above are repeated sequentially until the switching of content retransmission from 12 rebroadcasting devices 101A to 12 rebroadcasting devices 101B is completed. Specifically, when the control device 201 receives a notification of completion of the switching from rebroadcasting device 101A to rebroadcasting device 101B, after the execution of retransmission of content belonging to a certain channel has been switched from rebroadcasting device 101A to rebroadcasting device 101B, it creates a switching plan to switch the execution of retransmission of content belonging to other channels from rebroadcasting device 101A to rebroadcasting device 101B.

[0119] Figure 4 is a flowchart illustrating an example of the operation procedure when a control device according to the first embodiment of this disclosure transmits a switching start instruction.

[0120] Referring to Figure 4, first, the control device 201 creates a switching plan that includes the source rebroadcasting device 101A and the destination rebroadcasting device 101B (step S41).

[0121] Next, the control device 201 transmits an NTP synchronization instruction to the original rebroadcasting device 101A and the destination rebroadcasting device 101B (step S42).

[0122] Next, the control device 201 waits for the arrival of the synchronization completion notification and for a predetermined time to elapse since the NTP synchronization instruction was sent (NO in step S43 and NO in step S44).

[0123] Next, if the control device 201 receives a synchronization completion notification from the rebroadcasting devices 101A and 101B before a predetermined time has elapsed since sending the NTP synchronization instruction (YES in step S43), it sends a switching start instruction to the rebroadcasting devices 101A and 101B (step S45).

[0124] Next, the control device 201 waits for the arrival of the switching start notification and for a predetermined time to elapse since the switching start instruction was sent (NO in step S46 and NO in step S47).

[0125] Next, if the control device 201 receives a switching start notification from the rebroadcasting devices 101A and 101B before a predetermined time has elapsed since sending the switching start instruction (YES in step S46), it waits for the arrival of a switching completion notification and for a predetermined time to elapse since receiving the switching start notification (NO in step S48 and NO in step S49). If it receives a switching completion notification from the rebroadcasting devices 101A and 101B before a predetermined time has elapsed since receiving the switching start notification (YES in step S48), it terminates normally.

[0126] On the other hand, the control device 201 times out and terminates (step S50) if a predetermined time has elapsed between sending an NTP synchronization instruction and receiving a synchronization completion notification from the rebroadcasting devices 101A and 101B (YES in step S44), if a predetermined time has elapsed between sending a switching start instruction and receiving a switching start notification from the rebroadcasting devices 101A and 101B (YES in step S47), or if a predetermined time has elapsed between receiving a switching start notification and receiving a switching completion notification from the rebroadcasting devices 101A and 101B (YES in step S49).

[0127] Figure 5 is a flowchart illustrating an example of the operation procedure when a retransmission device according to the first embodiment of this disclosure switches to retransmission.

[0128] Referring to Figure 5, first, the rebroadcasting device 101 waits for an NTP synchronization instruction to arrive (NO in step S51), and when it receives an NTP synchronization instruction from the control device 201 (YES in step S51), it performs time synchronization according to the received NTP synchronization instruction (step S52).

[0129] Next, the rebroadcasting device 101 sends a synchronization completion notification to the control device 201 (step S53).

[0130] Next, the rebroadcasting device 101 waits for the arrival of a switching start instruction (NO in step S54), and when it receives a switching start instruction from the control device 201 (YES in step S54), it sends a switching start notification to the control device 201 as a response to the switching start instruction (step S55).

[0131] Next, the rebroadcasting device 101 performs a switching process (step S56).

[0132] Figure 6 is a flowchart showing an example of the operation procedure when a rebroadcasting device according to the first embodiment of this disclosure performs a switching process. Figure 6 shows details of step S56 shown in Figure 5 in the operational rebroadcasting device 101A.

[0133] Referring to Figure 6, first, the retransmission device 101A waits for the arrival of a SYN packet (NO in step S61), and when it receives a SYN packet from the retransmission device 101B (YES in step S61), it sends a SYN / ACK packet to the retransmission device 101B (step S62).

[0134] Next, the rebroadcasting device 101A waits for the arrival of an ACK packet and for a predetermined amount of time to elapse since the transmission of the SYN / ACK packet (NO in step S63 and NO in step S64).

[0135] Next, if the rebroadcasting device 101A receives an ACK packet from the rebroadcasting device 101B before a predetermined time has elapsed since it sent the SYN / ACK packet (YES in step S63), it waits for a configuration information request to arrive (NO in step S65).

[0136] Next, if the rebroadcasting device 101A receives a configuration information request from the rebroadcasting device 101B (YES in step S65), it transmits the configuration information C1 to the rebroadcasting device 101B using a TCP connection (step S66).

[0137] Next, the rebroadcasting device 101A waits for the arrival of timing information (NO in step S67), and when it receives timing information from the rebroadcasting device 101B (YES in step S67), it stores the received timing information in the storage unit 16 and sends a setting completion notification to the rebroadcasting device 101B using the TCP connection (step S68).

[0138] Next, the rebroadcasting device 101A waits for the switching timing to arrive (NO in step S69), and when the switching timing arrives (YES in step S69), it stops transmitting the content (step S70).

[0139] Next, the rebroadcasting device 101A sends a notification of completion of switching to the control device 201 (step S71).

[0140] On the other hand, if a predetermined amount of time elapses between the retransmission device 101A sending a SYN / ACK packet and the arrival of an ACK packet from the retransmission device 101B (YES in step S64), the device times out and interrupts the switching process (step S72).

[0141] Figure 7 is a flowchart showing an example of the operation procedure when a rebroadcasting device according to the first embodiment of this disclosure performs a switching process. Figure 7 shows details of step S56 shown in Figure 5 in the standby rebroadcasting device 101B.

[0142] Referring to Figure 7, first, the retransmission device 101B transmits a SYN packet to the retransmission device 101A (step S81).

[0143] Next, the retransmission device 101B waits for the arrival of a SYN / ACK packet (NO in step S82), and if it receives a SYN / ACK packet from the retransmission device 101A (YES in step S82), it sends an ACK packet to the retransmission device 101A (step S83).

[0144] Next, the rebroadcasting device 101B sends a configuration information request to the rebroadcasting device 101A using a TCP connection (step S84).

[0145] Next, the rebroadcasting device 101B waits for the arrival of setting information C1 and for a predetermined time to elapse since the setting information request was sent (NO in step S85 and NO in step S86).

[0146] Next, if the rebroadcasting device 101B receives setting information C1 from the rebroadcasting device 101A before a predetermined time has elapsed since sending the setting information request (YES in step S85), it determines the switching timing (step S87).

[0147] Next, the rebroadcasting device 101B transmits timing information indicating the switching timing to the rebroadcasting device 101A using a TCP connection (step S88).

[0148] Next, the rebroadcasting device 101B waits for the arrival of the setting completion notification and for a predetermined time to elapse since the transmission of timing information (NO in step S89 and NO in step S90).

[0149] Next, if the rebroadcasting device 101B receives a setting completion notification from the rebroadcasting device 101A before a predetermined time has elapsed since transmitting the timing information (YES in step S89), it waits for the switching timing to arrive (NO in step S92).

[0150] Next, when the switching timing arrives (YES in step S92), the rebroadcasting device 101B starts transmitting the content (step S93).

[0151] Next, the rebroadcasting device 101B sends a notification of completion of switching to the control device 201 (step S94).

[0152] On the other hand, if a predetermined time elapses between the transmission of a setting information request and the arrival of setting information C1 from the rebroadcasting device 101A (YES in step S86), or if a predetermined time elapses between the transmission of timing information and the arrival of a setting completion notification from the rebroadcasting device 101A (YES in step S90), the rebroadcasting device 101B times out and interrupts the switching process (step S95).

[0153] In the first embodiment of this disclosure, the retransmission system 301 is configured to sequentially switch the retransmission of content from multiple retransmission devices 101A to multiple retransmission devices 101B for each channel, but the system is not limited to this configuration. The retransmission system 301 may also be configured to simultaneously switch the retransmission of content from multiple retransmission devices 101A to multiple retransmission devices 101B.

[0154] Furthermore, in the rebroadcasting system 301 according to the first embodiment of this disclosure, the rebroadcasting device 101B is configured to send a SYN packet again if it times out and interrupts the switching process, but it is not limited to this. The rebroadcasting device 101B may be configured to send timing information to the rebroadcasting device 101A again instead of sending a SYN packet if a setting completion notification from the rebroadcasting device 101A does not arrive within a predetermined time after sending timing information. Also, the rebroadcasting device 101B may be configured to send a setting information request to the rebroadcasting device 101A again instead of sending a SYN packet if setting information C1 from the rebroadcasting device 101A does not arrive within a predetermined time after sending a setting information request.

[0155] Furthermore, while the rebroadcasting system 301 according to the first embodiment of this disclosure is configured such that the rebroadcasting device 101B transmits a SYN packet to the rebroadcasting device 101A and the rebroadcasting device 101A transmits a SYN / ACK packet to the rebroadcasting device 101B, the system is not limited to this configuration. The rebroadcasting system 301 may also be configured such that the rebroadcasting device 101A transmits a SYN packet to the rebroadcasting device 101B and the rebroadcasting device 101B transmits a SYN / ACK packet to the rebroadcasting device 101A.

[0156] Furthermore, while the rebroadcasting system 301 according to the first embodiment of this disclosure is configured such that the rebroadcasting device 101B determines the switching timing and transmits the timing information to the rebroadcasting device 101A, the system is not limited to this configuration. In the rebroadcasting system 301, the rebroadcasting device 101A may determine the switching timing and transmit the timing information to the rebroadcasting device 101B.

[0157] Next, other embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and their descriptions will not be repeated.

[0158] <Second Embodiment> This embodiment relates to a rebroadcasting system 302 that receives an IP packet containing content and retransmits the content in a broadcast signal, in contrast to the rebroadcasting system 301 according to the first embodiment. Except for the details described below, it is the same as the rebroadcasting system 301 according to the first embodiment.

[0159] Figure 8 is a diagram showing the configuration of a retransmission system according to a second embodiment of the present disclosure. Referring to Figure 8, compared to retransmission system 301, retransmission system 302 includes switch devices 82, 92A, 92B and multiplexers 122A, 122B, 132 instead of antennas 81A, 81B, distributor 91, and switch devices 121, 131. Also, compared to retransmission system 301, retransmission system 302 includes retransmission device 102 instead of retransmission device 101, and control device 202 instead of control device 201. Hereinafter, switch devices 92A, 92B will each be referred to as switch device 92, and multiplexers 122A, 122B will each be referred to as multiplexer 122.

[0160] As an example, the rebroadcasting system 302 comprises 12 rebroadcasting devices 102A, which are the operational rebroadcasting devices 102, and 12 rebroadcasting devices 102B, which are the standby rebroadcasting devices 102.

[0161] Each rebroadcasting device 102A is connected to a switch device 92A via a LAN cable. Each rebroadcasting device 102B is connected to a switch device 92B via a LAN cable.

[0162] The control device 202 is connected to interface units 111A and 112B via a switch device 211. For example, the control device 202 is connected to interface units 111A and 111B via a LAN cable that is physically different from the LAN cable connecting the rebroadcasting device 102A and the switch device 92A, and also different from the LAN cable connecting the rebroadcasting device 102B and the switch device 92B.

[0163] After each retransmission device 102 in the retransmission system 302 is started up, the control device 202 transmits setting information C2 regarding the retransmission of content to the operational retransmission device 102A via the switch device 211 and interface unit 111A, and transmits a standby instruction S2 indicating that the device should wait for the retransmission of content to proceed to the standby retransmission device 102B via the switch device 211 and interface unit 111B.

[0164] For example, rebroadcasting device 102A receives an IP flow, which is a series of IP packets containing content, from an IP network or a headend device (not shown) via switch devices 82 and 92A. Similarly, rebroadcasting device 102B receives an IP flow, which is a series of IP packets containing content, from an IP network or the headend device via switch devices 82 and 92B.

[0165] Rebroadcasting device 102B does not rebroadcast content in its initial state. On the other hand, rebroadcasting device 102A does rebroadcast content in its initial state.

[0166] More specifically, each of the 12 retransmission devices 102A is assigned, for example, a different channel. The retransmission device 102A acquires content belonging to its assigned channel from IP packets according to the configuration information C2 received from the control device 202, generates a broadcast signal containing the acquired content, and transmits the generated broadcast signal to the STB 151 at the subscriber's home via the multiplexers 122A, 132 and the cable television network 142.

[0167] The STB151 acquires content from the broadcast signal received from the rebroadcasting device 102 via the cable television network 142, and plays back the acquired content on a display device (not shown).

[0168] (Rebroadcasting device) Figure 9 shows the configuration of a rebroadcasting device according to a second embodiment of the present disclosure. Referring to Figure 9, the rebroadcasting device 102, compared to the rebroadcasting device 101, includes an IP transceiver 21, a signal processing unit 22, a signal output unit 23, and a control unit 24 instead of a tuner 11, a packet processing unit 12, an IP transceiver 13, and a control unit 14. The IP transceiver 21 is an example of a content receiving unit. The signal output unit 23 is an example of a content transmission unit. The control unit 24 is an example of an instruction receiving unit, an example of a setting unit, and an example of a switching unit. Some or all of the IP transceiver 21, signal processing unit 22, signal output unit 23, and control unit 24 are implemented, for example, by a circuit including one or more processors.

[0169] The IP transceiver 21 receives IP packets containing content from the switch device 92. The IP transceiver 21 also receives a reception start instruction from the control unit 24. In accordance with the reception start instruction received from the control unit 24, the IP transceiver 21 processes the reception of IP packets containing content belonging to the channel assigned to the rebroadcasting device 102. The IP transceiver 21 outputs the received IP packets to the signal processing unit 22.

[0170] Each time the signal processing unit 22 receives an IP packet from the IP transmission / reception unit 21, it obtains a TS packet from the received IP packet and performs modulation processing on the obtained TS packet to generate a digital signal containing content. The signal processing unit 22 then outputs the generated digital signal to the signal output unit 23.

[0171] The signal output unit 23 transmits the content received by the IP transmission / reception unit 21. The signal output unit 23 also receives an output start instruction from the control unit 24. In accordance with the output start instruction received from the control unit 24, the signal output unit 23 upconverts the broadcast signal, which is an analog conversion of the digital signal received from the signal processing unit 22, to a frequency corresponding to the channel assigned to the rebroadcasting device 102, and outputs it to the multiplexer 122.

[0172] The IP transceiver 21 can switch between a receive-on state, which processes the reception of IP packets containing content, and a receive-off state, which does not process the reception of IP packets containing content. For example, the IP transceiver 21 is set to the receive-off state when the rebroadcasting device 102 is started up.

[0173] The signal output unit 23 can switch between an output-on state, which outputs a broadcast signal, and an output-off state, which does not output a broadcast signal. For example, the signal output unit 23 is set to the output-off state when the rebroadcasting device 102 is started up.

[0174] (Initial settings) The control unit 24 in the rebroadcasting device 102B receives a standby instruction S2 from the control device 202 and maintains the reception-off state of the IP transmission / reception unit 21 and the output-off state of the signal output unit 23 in accordance with the received standby instruction S2.

[0175] The control unit 24 in the rebroadcasting device 102A receives configuration information C2 from the control device 202. The configuration information C2 indicates the reception configuration information for the IP packet containing the content and the signal information related to the broadcast signal to be output. For example, the reception configuration information includes the destination IP address, destination port number, and VLAN tag of the IP packet to be received. For example, the signal information includes the frequency F2 and output level of the broadcast signal to be output. The control unit 24 stores the received configuration information C2 in the storage unit 16.

[0176] In the rebroadcasting device 102A, the control unit 24 switches the IP transceiver 21 to the receive-on state and the signal output unit 23 to the output-on state according to the setting information C2 received from the control device 202. More specifically, the control unit 24 outputs a reception start instruction including the setting information C2 to the IP transceiver 21 and outputs an output start instruction including the setting information C2 to the signal output unit 23.

[0177] The IP transceiver 21 receives a reception start instruction from the control unit 24 and, according to the configuration information C2 included in the received reception start instruction, starts the IP packet reception process and output to the signal processing unit 22.

[0178] The signal output unit 23 receives an output start instruction from the control unit 24 and starts outputting the broadcast signal according to the setting information C2 included in the received output start instruction. More specifically, the signal output unit 23 upconverts the broadcast signal to the frequency F2 indicated by the setting information C2 and outputs it to the multiplexer 122.

[0179] (Switching process) In the rebroadcasting system 302, the rebroadcasting device 102 that performs content retransmission is switched over in the same manner as in the rebroadcasting system 301.

[0180] More specifically, the rebroadcasting devices 102A and 102B establish a TCP connection by exchanging TCP packets via the switch devices 92 and 82, and use the TCP connection to send and receive configuration information C2 and timing information. Rebroadcasting device 102A stops transmitting content at the switching timing, and rebroadcasting device 102B starts transmitting content at the switching timing.

[0181] Next, other embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and their descriptions will not be repeated.

[0182] <Third Embodiment> This embodiment relates to a retransmission system 303 that receives an IP packet containing content and retransmits the content in the IP packet, compared to the retransmission system 301 according to the first embodiment. Except for the details described below, it is the same as the retransmission system 301 according to the first embodiment and the retransmission system 302 according to the second embodiment.

[0183] Figure 10 is a diagram showing the configuration of a rebroadcasting system according to a third embodiment of the present disclosure. Referring to Figure 10, compared to rebroadcasting system 301, rebroadcasting system 303 includes a switch device 82 and switch devices 92A and 92B instead of antennas 81A and 81B and distributor 91. Also, compared to rebroadcasting system 301, rebroadcasting system 303 includes a rebroadcasting device 103 instead of rebroadcasting device 101 and a control device 203 instead of control device 201.

[0184] As an example, the rebroadcasting system 303 comprises 12 rebroadcasting devices 103A, which are operational rebroadcasting devices 103, and 12 rebroadcasting devices 103B, which are standby rebroadcasting devices 103.

[0185] Each rebroadcasting device 103A is connected to a switch device 92A via a LAN cable. Additionally, each rebroadcasting device 103A is connected to a switch device 121A via a LAN cable.

[0186] Each rebroadcasting device 103B is connected to a switch device 92B via a LAN cable. Additionally, each rebroadcasting device 103B is connected to a switch device 121B via a LAN cable.

[0187] The control device 203 is connected to interface units 111A and 112B via a switch device 211. For example, the control device 203 is connected to interface units 111A and 111B via a LAN cable that is physically different from the LAN cable connecting the rebroadcasting device 103A and the switch device 92A, physically different from the LAN cable connecting the rebroadcasting device 103A and the switch device 121A, physically different from the LAN cable connecting the rebroadcasting device 103B and the switch device 92B, and physically different from the LAN cable connecting the rebroadcasting device 103B and the switch device 121B.

[0188] After each retransmission device 103 in the retransmission system 303 is started up, the control device 203 transmits setting information C3 regarding the retransmission of content to the operational retransmission device 103A via the switch device 211 and interface unit 111A, and transmits a standby instruction S3 indicating that the device should wait for the retransmission of content to be resumed to the standby retransmission device 103B via the switch device 211 and interface unit 111B.

[0189] For example, rebroadcasting device 103A receives an IP flow, which is a series of IP packets containing content, from an IP network or a headend device (not shown) via switch devices 82 and 92A. Similarly, rebroadcasting device 103B receives an IP flow, which is a series of IP packets containing content, from an IP network or the headend device via switch devices 82 and 92B.

[0190] Rebroadcasting device 103B does not rebroadcast content in its initial state. On the other hand, rebroadcasting device 103A does rebroadcast content in its initial state.

[0191] More specifically, each of the 12 rebroadcasting devices 103A is assigned, for example, a different channel. The rebroadcasting device 103A acquires content belonging to its assigned channel from IP packets according to the configuration information C3 received from the control device 203, generates an IP packet containing the acquired content, and multicasts the generated IP packet to the STB 151 at the subscriber's home via the switch devices 121A, 131 and the IP network 141.

[0192] STB151 acquires content from IP packets received from the rebroadcasting device 103 via the IP network 141, and plays the acquired content on a display device (not shown).

[0193] (Rebroadcasting device) Figure 11 shows the configuration of a rebroadcasting device according to a third embodiment of the present disclosure. Referring to Figure 11, the rebroadcasting device 103, compared to the rebroadcasting device 101, includes an IP transceiver unit 21, a packet processing unit 32, and a control unit 34 instead of a tuner 11, a packet processing unit 12, and a control unit 14. This is an example of an instruction receiving unit, an example of a setting unit, and an example of a switching unit. Some or all of the IP transceiver unit 21, packet processing unit 32, IP transceiver unit 13, and control unit 34 are implemented, for example, by a processing circuit (Circuitry) including one or more processors.

[0194] The IP transceiver 21 receives IP packets containing content from the switch device 92. The IP transceiver 21 also receives a reception start instruction from the control unit 34. In accordance with the reception start instruction received from the control unit 34, the IP transceiver 21 processes the reception of IP packets containing content belonging to the channel assigned to the rebroadcasting device 103. The IP transceiver 21 outputs the received IP packets to the packet processing unit 32.

[0195] Each time the packet processing unit 32 receives an IP packet from the IP transceiver 21, it obtains a TS packet from the received IP packet. Each time the packet processing unit 32 obtains a TS packet, it obtains the count value of the counter 15, generates a TTS packet with the count value added as a timestamp to the generated TS packet, and outputs it to the IP transceiver 13.

[0196] The IP transceiver 13 transmits the content received by the IP transceiver 21. For example, the IP transceiver 13 sends an IP flow, which is a series of IP packets containing the content, to the switch device 121. More specifically, the IP transceiver 13 generates an IP packet containing one or more TTS packets received from the packet processing unit 32, includes the generated IP packet in a frame, and sends it to the switch device 121.

[0197] The IP transceiver 21 can switch between a receive-on state, which processes the reception of IP packets containing content, and a receive-off state, which does not process the reception of IP packets containing content. For example, the IP transceiver 21 is set to the receive-off state when the rebroadcasting device 103 is started up.

[0198] The IP transceiver 13 can switch between a transmit-on state, which transmits IP flows, and a transmit-off state, which does not transmit IP flows. For example, the IP transceiver 13 is set to the transmit-off state when the rebroadcasting device 103 is started up.

[0199] (Initial settings) The control unit 34 in the rebroadcasting device 103B receives a standby instruction S3 from the control device 203 and maintains the receive-off state of the IP transceiver 21 and the transmit-off state of the IP transceiver 13 in accordance with the received standby instruction S3.

[0200] The control unit 34 in the rebroadcasting device 103A receives configuration information C3 from the control device 203. The configuration information C3 indicates the configuration information for receiving IP packets containing content and the configuration information for transmitting content. The control unit 34 stores the received configuration information C3 in the storage unit 16.

[0201] In the rebroadcasting device 103A, the control unit 34 switches the IP transceiver 21 to the receive-on state and the IP transceiver 13 to the transmit-on state according to the setting information C3 received from the control device 203. More specifically, the control unit 34 outputs a start-reception instruction including the setting information C3 to the IP transceiver 21 and a start-transmitting instruction including the setting information C3 to the IP transceiver 13.

[0202] The IP transceiver 21 receives a reception start instruction from the control unit 34 and, according to the configuration information C3 included in the received reception start instruction, starts the IP packet reception process and output to the packet processing unit 32.

[0203] The IP transceiver 13 receives a transmission start instruction from the control unit 34 and starts transmitting an IP packet containing content according to the configuration information C3 included in the received transmission start instruction.

[0204] (Switching process) In the rebroadcasting system 303, the rebroadcasting device 103 that performs content retransmission is switched over in the same manner as in the rebroadcasting system 301.

[0205] More specifically, the rebroadcasting devices 103A and 103B establish a TCP connection by exchanging TCP packets via the switch devices 121 and 131, and use this TCP connection to send and receive configuration information C3 and timing information, etc. Then, rebroadcasting device 103A stops transmitting content at the switching timing. Rebroadcasting device 103B starts transmitting content at the switching timing. Alternatively, rebroadcasting devices 103A and 103B may establish a TCP connection by exchanging TCP packets via the switch devices 92 and 82, and use this TCP connection to send and receive configuration information C3 and timing information, etc.

[0206] Next, other embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and their descriptions will not be repeated.

[0207] <Fourth Embodiment> This embodiment relates to a rebroadcasting system 304 that receives a broadcast signal containing content and retransmits the content included in the broadcast signal, compared to the rebroadcasting system 301 according to the first embodiment. Except for the details described below, it is the same as the rebroadcasting system 301 according to the first embodiment, the rebroadcasting system 302 according to the second embodiment, and the rebroadcasting system 303 according to the third embodiment.

[0208] Figure 12 is a diagram showing the configuration of a rebroadcasting system according to a fourth embodiment of the present disclosure. Referring to Figure 12, compared to rebroadcasting system 301, rebroadcasting system 304 includes multiplexers 122 and 132 instead of switching devices 121 and 131. Also, compared to rebroadcasting system 301, rebroadcasting system 304 includes a rebroadcasting device 104 instead of rebroadcasting device 101, and a control device 204 instead of control device 201.

[0209] As an example, the rebroadcasting system 304 comprises 12 rebroadcasting devices 104A, which are operational rebroadcasting devices 104, and 12 rebroadcasting devices 104B, which are standby rebroadcasting devices 104.

[0210] The control device 204 is connected to interface units 111A and 112B via a switch device 211.

[0211] After each retransmission device 104 in the retransmission system 304 is started up, the control device 204 transmits setting information C4 regarding the retransmission of content to the operational retransmission device 104A via the switch device 211 and interface unit 111A, and transmits a standby instruction S4 indicating that the device should wait for the retransmission of content to proceed to the standby retransmission device 104B via the switch device 211 and interface unit 111B.

[0212] The rebroadcasting devices 104A and 104B receive the broadcast signal containing the content from the distributors 91A and 91B, respectively.

[0213] Rebroadcasting device 104B does not rebroadcast content in its initial state. On the other hand, rebroadcasting device 104A does rebroadcast content in its initial state.

[0214] More specifically, each of the 12 retransmission devices 104A is assigned, for example, a different channel. The retransmission device 104A acquires content belonging to its assigned channel from the broadcast signal according to the setting information C4 received from the control device 204, generates a broadcast signal containing the acquired content, and transmits the generated broadcast signal to the STB 151 at the subscriber's home via the multiplexers 122A, 132 and the cable television network 142.

[0215] The STB151 acquires content from the broadcast signal received from the rebroadcasting device 104 via the cable television network 142, and plays back the acquired content on a display device (not shown).

[0216] (Rebroadcasting device) Figure 13 shows the configuration of a retransmission device according to a fourth embodiment of the present disclosure. Referring to Figure 13, the retransmission device 104, compared to the retransmission device 101, includes a signal processing unit 42, a signal output unit 23, and a control unit 44 instead of a packet processing unit 12, an IP transmission / reception unit 13, and a control unit 14. The control unit 44 is an example of an instruction receiving unit, an example of a setting unit, and an example of a switching unit. Some or all of the tuner 11, signal processing unit 42, signal output unit 23, and control unit 44 are implemented, for example, by a circuit including one or more processors.

[0217] The tuner 11 receives a broadcast signal containing content from the distributor 91. The tuner 11 also receives a demodulation start instruction from the control unit 44. In accordance with the demodulation start instruction received from the control unit 44, the tuner 11 performs demodulation processing on the broadcast signal received from the distributor 91, thereby generating a stream containing content belonging to the channel assigned to the rebroadcasting device 104. The tuner 11 outputs the generated stream to the signal processing unit 42.

[0218] The signal processing unit 42 generates multiple TS packets, each with a data length of 188 bytes, containing the data divided from the stream received from the tuner 11. The signal processing unit 42 generates a digital signal containing the content by performing modulation processing on the acquired TS packets. The signal processing unit 42 outputs the generated digital signal to the signal output unit 23.

[0219] The signal output unit 23 transmits the content received by the tuner 11. The signal output unit 23 also receives an output start instruction from the control unit 44. In accordance with the output start instruction received from the control unit 44, the signal output unit 23 upconverts the broadcast signal, which is obtained by converting the digital signal received from the signal processing unit 42 into an analog signal, to a frequency corresponding to the channel assigned to the rebroadcasting device 104, and outputs it to the multiplexer 122.

[0220] The tuner 11 can switch between a generation-on state, which generates a stream containing content, and a generation-off state, which does not generate a stream. For example, the tuner 11 is set to the generation-off state when the rebroadcasting device 104 is started up.

[0221] The signal output unit 23 can switch between an output-on state, which outputs a broadcast signal, and an output-off state, which does not output a broadcast signal. For example, the signal output unit 23 is set to the output-off state when the rebroadcasting device 104 is started up.

[0222] (Initial settings) The control unit 44 in the rebroadcasting device 104B receives a standby instruction S4 from the control device 204 and maintains the tuner 11 in the generation-off state and the signal output unit 23 in the output-off state according to the received standby instruction S4.

[0223] The control unit 44 in the rebroadcasting device 104A receives setting information C4 from the control device 204. The setting information C4 indicates the frequency F1 of the broadcast signal to be demodulated by the tuner 11 and the signal information related to the broadcast signal to be output. The control unit 44 stores the received setting information C4 in the storage unit 16.

[0224] In the rebroadcasting device 104A, the control unit 44 switches the tuner 11 to the generation ON state and the signal output unit 23 to the output ON state according to the setting information C4 received from the control device 204. More specifically, the control unit 44 outputs a demodulation start instruction including the setting information C4 to the tuner 11 and an output start instruction including the setting information C4 to the signal output unit 23.

[0225] The tuner 11 receives a demodulation start instruction from the control unit 44 and starts generating and outputting a stream containing content according to the setting information C4 included in the received demodulation start instruction.

[0226] The signal output unit 23 receives an output start instruction from the control unit 44 and starts outputting the broadcast signal according to the setting information C4 included in the received output start instruction.

[0227] (Switching process) In the rebroadcasting system 304, the rebroadcasting device 104 that performs content retransmission is switched over in the same manner as in the rebroadcasting system 301.

[0228] More specifically, the rebroadcasting devices 104A and 104B establish a TCP connection by exchanging TCP packets via the interface unit 111 and the switch device 211, and use the TCP connection to send and receive configuration information C4 and timing information. Rebroadcasting device 104A stops transmitting content at the switching timing, and rebroadcasting device 104B starts transmitting content at the switching timing.

[0229] The embodiments described above should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than the above description, and all modifications within the meaning and scope equivalent to the claims are intended to be included.

[0230] Each process (each function) of the above-described embodiment is implemented by a processing circuit (Circuitry) including one or more processors. The processing circuit may consist of one or more memories, various analog circuits, various digital circuits, etc., in addition to the one or more processors, as well as an integrated circuit. The one or more memories store programs (instructions) that cause the one or more processors to execute each of the above processes. The one or more processors may execute each of the above processes according to the programs read from the one or more memories, or they may execute each of the above processes according to logic circuits that have been pre-designed to execute each of the above processes. The processors may be various processors suitable for computer control, such as a CPU (Central Processing Unit), GPU (Graphics Processing Unit), DSP (Digital Signal Processor), FPGA (Field Programmable Gate Array), and ASIC (Application Specific Integrated Circuit). Furthermore, the physically separated multiple processors may cooperate with each other to execute each of the above processes. For example, the processors installed in each of several physically separated computers may cooperate with each other via a network such as a LAN (Local Area Network), WAN (Wide Area Network), and the Internet to perform the above processes. The program may be installed in the memory via the network from an external server device, or it may be distributed on a recording medium such as a CD-ROM (Compact Disc Read Only Memory), DVD-ROM (Digital Versatile Disk Read Only Memory), and semiconductor memory, and then installed in the memory from the recording medium.

[0231] The above description includes the following features. [Note 1] A retransmission system comprising a plurality of retransmission devices for receiving and retransmitting content, and a control device, wherein a switching method for switching the retransmission of the content from the operational retransmission device to the standby retransmission device, The steps include: synchronizing the time between the rebroadcasting device of the operational system and the rebroadcasting device of the standby system; The steps include: giving a switching start instruction from the control device to the operational rebroadcasting device and the standby rebroadcasting device; The steps include providing the standby rebroadcasting system with setting information indicating the settings for retransmitting the content in the operational rebroadcasting system, The steps include setting the switching timing through communication between the rebroadcasting device of the operational system and the rebroadcasting device of the standby system, The switching timing includes the step of switching the retransmission of the content from the operational retransmission device to the standby retransmission device, A switching method in which, in the step of setting the switching timing, the switching timing is set by communication using a communication connection that conforms to TCP.

[0232] [Note 2] A rebroadcasting device in a rebroadcasting system that retransmits content, Equipped with a processing circuit, The aforementioned processing circuit is Upon receiving the aforementioned content, Send the received content, Upon receiving a switching start instruction to switch the execution of retransmission of the aforementioned content between other retransmission devices, By communicating with the other rebroadcasting device indicated by the received switching start instruction, a switching timing is set, which is the timing at which the start and stop of the transmission of the content should be switched. A rebroadcasting device that switches the start and stop of transmitting the content at the set switching timing. [Explanation of symbols]

[0233] 11 tuners 12,32 Packet Processing Unit 13,21 IP Transceiver 14,24,34,44 Control Unit 15 counters 16 Memory section 22,42 Signal Processing Unit 23 Signal output section 81, 81A, 81B antennas 82, 92, 92A, 92B, 121, 121A, 121B, 131, 211 Switching device 91,91A,91B distributor 101, 101A, 101B, 102, 102A, 102B, 103, 103A, 103B, 104, 104A, 104B Rebroadcasting device 111, 111A, 111B Interface Unit 122,122A,122B,132 Multiplexer 141 IP network 142 Cable television networks 151 STB 201 Control device 301, 302, 303, 304 Rebroadcast System SA, SB Subchassis

Claims

1. A retransmission system comprising a plurality of retransmission devices for receiving and retransmitting content, and a control device, wherein a switching method for switching the retransmission of the content from the operational retransmission device to the standby retransmission device, The steps include: synchronizing the time between the rebroadcasting device of the operational system and the rebroadcasting device of the standby system; The steps include: giving a switching start instruction from the control device to the operational rebroadcasting device and the standby rebroadcasting device; The steps include providing the standby rebroadcasting system with setting information indicating the settings for retransmitting the content in the operational rebroadcasting system, The steps include setting the switching timing through communication between the rebroadcasting device of the operational system and the rebroadcasting device of the standby system, A switching method comprising the step of switching the retransmission of the content from the operational retransmission device to the standby retransmission device at the aforementioned switching timing.

2. The aforementioned switching method further includes, The steps include defining the rebroadcasting equipment of the multiple operational systems subject to switching as an operational system set, The step includes defining a set of multiple standby system rebroadcasting devices that are subject to switching as a standby system set, The switching method according to claim 1, which is a method for switching the retransmission of the content from the operational system's retransmission device to the standby system's retransmission device for a pair of operational system retransmission devices included in the operational system set and standby system retransmission devices included in the standby system set.

3. The aforementioned operational system set is installed in one rack. The aforementioned standby system set is installed in a separate rack from the aforementioned rack. The switching method according to claim 2, wherein the step preceding the step of switching the retransmission of the content is performed for all pairs in the operational set and the standby set, and then the step of switching the retransmission of the content is performed for all pairs in the operational set and the standby set.

4. The aforementioned switching method further includes, The process includes a step of performing a connection establishment process to establish a communication connection between the operational rebroadcasting device and the standby rebroadcasting device, In the step of setting the switching timing, the switching timing is set by communication using the communication connection. The aforementioned switching method further includes, The switching method according to any one of claims 1 to 3, further comprising the step of performing the connection establishment process again if the setting of the switching timing fails.

5. A rebroadcasting system that retransmits content, Multiple rebroadcasting devices that receive the aforementioned content and retransmit the received content, Equipped with a control device, The rebroadcasting device in the operational system and the rebroadcasting device in the standby system perform time synchronization. The control device transmits a switching start instruction to the operational retransmission device and the standby retransmission device to switch the retransmission of the content from the operational retransmission device to the standby retransmission device. The operational rebroadcasting device transmits setting information indicating the settings for retransmitting the content to the standby rebroadcasting device. The rebroadcasting device of the operational system and the rebroadcasting device of the standby system set the switching timing through communication between the rebroadcasting device of the operational system and the rebroadcasting device of the standby system. The rebroadcasting device of the operational system stops transmitting the content at the switching timing. The standby rebroadcasting device is a rebroadcasting system that starts transmitting the content at the switching timing.

6. A rebroadcasting device in a rebroadcasting system that retransmits content, The content receiving unit that receives the aforementioned content, A content transmission unit that transmits the content received by the content receiving unit, An instruction receiving unit that receives a switching start instruction to switch the execution of retransmission of the aforementioned content between other retransmission devices, A setting unit communicates with the other rebroadcasting device indicated by the switching start instruction received by the instruction receiving unit, and sets a switching timing which is the timing at which the content transmission unit should switch the start and stop of transmitting the content. A rebroadcasting device comprising: a switching unit that switches the start and stop of the transmission of the content by the content transmission unit at the switching timing set by the setting unit.

Images