JP7319007B2 - Communication system, communication device, communication method and program - Google Patents

Description

The present invention relates to a communication system, communication device, communication method and program.

There is a technology called Push-to-Talk that realizes conversation between terminals using data transfer technology on the Internet. A communication system that implements Push-to-Talk includes a packet transfer device (communication device) that transfers packets containing encoded voice data and a control device that controls the packet transfer device.

The packet transfer device is also called a U-Plane server because it is responsible for transferring user data. The control device is also called a C-Plane server.

Packet transfer devices are often redundant in order to improve the availability of communication systems. Patent document 1 aims to provide a redundant packet processing device and a redundancy method thereof that do not place a heavy load on the currently used packet processing device even when user traffic increases in the redundantly configured packet processing device. It is stated that

JP 2006-279375 A

It should be noted that the disclosure of the prior art document mentioned above is incorporated herein by reference. The following analysis was made by the inventors.

As described above, a Push-to-Talk communication system includes a packet transfer device (U-Plane server). In Push-to-Talk, it is desirable that the intervals between consecutively transmitted packets be short. For example, if the interval between a packet (a packet containing voice data) sent from the sender and the following packet is too long, problems such as voice interruption may occur. In order to solve such a problem, countermeasures such as providing a buffer on the receiving side are taken, but the size of the buffer is also limited.

Considering the above situation, a technique for shortening the packet processing time (the time from packet reception to output) in the packet transfer device may be applied to the U-Plane server. Specifically, a technique for high-speed packet transfer called Fast Path is applied to the U-Plane server.

Fastpath has a table (flow table) for processing packets at high speed. Information for identifying a flow to which a packet belongs and processing for a packet belonging to the identified flow are stored in the flow table in association with each other. Information for identifying a flow includes an IP (Internet protocol) address, protocol number, port number, and the like. Processing for packets belonging to the specified flow includes packet filtering (discarding) and packet forwarding from a specified port.

A U-Plane server with fastpath installed needs to be set in advance before packet transfer by the server (preset is required).

When the U-Plane servers are redundant, the active U-Plane server is preconfigured, but the standby U-Plane server is not preconfigured. Therefore, when system switching occurs due to a failure occurring in the active U-Plane server, the standby U-Plane server needs to be set in advance. Such redoing of the presetting becomes a factor that lengthens the time until the communication system becomes ready for communication.

The present invention is a communication system, a communication device, a communication method, and a program that support a communication method that requires prior setting and contribute to shortening the time required for system switching in a system that includes communication devices that constitute a redundant system. The main purpose is to provide

According to a first aspect of the present invention or disclosure, the operating system includes a plurality of redundantly configured communication devices, and a control device that transmits call information to an active communication device among the plurality of communication devices. The system communication device transfers the received call information to a standby communication device among the plurality of communication devices, and the standby communication device transfers the flow entry to the active system based on the transferred call information. A communication system is provided that generates a communication device before it fails .

According to a second aspect of the present invention or disclosure, when the own device is an active device, the call information acquired from the control device is transferred to another standby device, and the own device is a standby device. , there is provided a communication device that generates a flow entry based on the transferred call information before a failure occurs in the active communication device .

According to a third aspect of the present invention or disclosure, in a communication system including a plurality of redundantly configured communication devices and a control device that transmits call information to an active communication device among the plurality of communication devices and the active communication device transfers the received call information to a standby communication device among the plurality of communication devices, and the standby communication device creates a flow entry based on the transferred call information. There is provided a communication method for generating before a failure occurs in the active communication device .

According to a fourth aspect of the present invention or disclosure, when the own device is an active device, a process of transferring call information acquired from a control device to another standby device; a program for causing a computer installed in the communication device to execute a process of generating a flow entry before a failure occurs in the active communication device based on the transferred call information when the device is provided.
This program can be recorded in a computer-readable storage medium. The storage medium can be non-transient such as semiconductor memory, hard disk, magnetic recording medium, optical recording medium, and the like. The invention can also be embodied as a computer program product.

According to each aspect of the present invention and disclosure, a communication system that supports a communication method that requires presetting and contributes to shortening the time required for system switching in a system that includes communication devices that constitute a redundant system, A communication device, communication method and program are provided.

1 is a diagram for explaining an overview of an embodiment; FIG. 1 is a diagram illustrating an example of a schematic configuration of a communication system according to a first embodiment; FIG. 3 is a diagram showing an example of a processing configuration of a U-Plane server according to the first embodiment; FIG. 4 is a sequence diagram showing an example of the operation of the communication system according to the first embodiment; FIG. FIG. 2 is a diagram showing an example of the hardware configuration of a U-Plane server; FIG.

First, an overview of one embodiment will be described. It should be noted that the drawing reference numerals added to this outline are added to each element for convenience as an example to aid understanding, and the description of this outline does not intend any limitation. Also, connecting lines between blocks in each figure include both bi-directional and uni-directional. The unidirectional arrows schematically show the flow of main signals (data) and do not exclude bidirectionality. Furthermore, in the circuit diagrams, block diagrams, internal configuration diagrams, connection diagrams, etc. disclosed in the present application, an input port and an output port exist at the input end and the output end of each connection line, respectively, although not explicitly shown. Input/output interfaces are similar.

A communication system according to an embodiment includes a plurality of redundantly configured communication devices 101, and a control device 102 that transmits call information to the active communication device 101 among the plurality of communication devices 101 (see FIG. 1). ). The active communication device 101 transfers the received call information to the standby communication device 101 among the plurality of communication devices 101 . Based on the transferred call information, the standby-system communication device 101 generates information for transferring the packet before it becomes the active-system communication device 101 .

The communication device 101 included in the above communication system is compatible with a communication method that requires preprocessing (for example, fastpath), and constitutes a redundant system. In the redundant system, even when switching from the active system to the standby system occurs, the information necessary for packet transfer is prepared (generated) in the standby system in advance, so the advance necessary for the above communication method Communication can be continued without delay without redoing the process.

Specific embodiments will be described in more detail below with reference to the drawings. In addition, the same code|symbol is attached|subjected to the same component in each embodiment, and the description is abbreviate|omitted.

[First embodiment]
The first embodiment will be described in more detail with reference to the drawings.

FIG. 2 is a diagram illustrating an example of a schematic configuration of a communication system according to the first embodiment; The communication system shown in FIG. 2 provides a Push-to-Talk service in which commercial radio functions are added to public network LTE (Long Term Evolution) technology.

The U-Plane servers 20-1 and 20-2, which are included in the communication system and which communicate (transfer) user information, use Fastpath (a communication method requiring prior setting) as a communication function. In other words, the plurality of U-Plane servers 20 are servers that perform packet transfer using a communication method that requires prior setting before execution of packet transfer.

The U-Plane servers 20-1 and 20-2 are made redundant in case of failure. In other words, the communication system includes a plurality of redundantly configured communication devices (packet transfer device, U-Plane server 20).

Referring to FIG. 2, the communication system includes C-Plane server 10, U-Plane servers 20-1 and 20-2, EPC (Evolved Packet Core) 30, eNodeB (Evolved Node B) 40, user terminal 50 and .

If there is no particular reason to distinguish between the U-Plane servers 20-1 and 20-2, they will simply be referred to as "U-Plane server 20". In FIG. 2, the U-Plane server 20-1 is the active server, and the U-Plane server 20-2 is the standby server. The C-Plane server 10 and U-Plane server 20 are connected by a dedicated control line. The U-Plane servers 20 are connected to each other by cables such as Ethernet (registered trademark).

In the communication system according to the first embodiment, a plurality of U-Plane servers 20 form a packet transfer network. transfer.

The C-Plane server 10 is a control device for realizing Push-to-Talk service. Specifically, the C-Plane server 10 performs “call control” such as outgoing calls, incoming calls, responses, and disconnections for realizing calls between user terminals 50 . As part of the call control, the C-Plane server 10 transmits "call information" to the active U-Plane server 20-1.

The call information includes information such as the IP (Internet protocol) address of the user terminal 50, protocol to be used, port number, transfer destination port, and the like.

The C-Plane server 10 transmits call information to the active U-Plane server 20-1 among the plurality of U-Plane servers 20. FIG.

Based on the acquired call information, the active U-Plane server 20-1 generates a flow entry (information to be stored in the flow table) for forwarding the received packet by fastpath, and transmits the packet according to the flow entry. make a transfer. Further, the active U-Plane server 20-1 transfers the acquired call information to the standby U-Plane server 20-2. That is, the active U-Plane server 20-1 transfers the received call information to the standby U-Plane server 20-2 among the plurality of U-Plane servers 20. FIG.

Based on the transferred call information, the standby U-Plane server 20-2 generates information (flow entry) for transferring packets before it becomes the active U-Plane server. That is, the standby U-Plane server 20-2 generates a flow entry from the acquired call information, and prepares for packet transfer according to the flow entry when system switching occurs. As described above, in the communication system according to the first embodiment, in order to continue communication without delay when system switching occurs, preset settings necessary for the fast path are also performed in the standby system.

A packet transmitted from the user terminal 50 reaches the other terminal via the eNodeB 40 as the LTE base station device, the EPC 30 as the core network, and the active U-Plane server 20 .

FIG. 3 is a diagram showing an example of a processing configuration (processing modules) of the U-Plane server 20 according to the first embodiment. Referring to FIG. 3, the U-Plane server 20 includes a communication control section 201, a fastpath control section 202, a packet transfer section 203, and a storage section 204. FIG.

The communication control unit 201 is means for controlling communication with other devices (C-Plane server 10, other U-Plane server 20). When acquiring the “call information” from the C-Plane server 10 , the communication control unit 201 stores the acquired call information in the storage unit 204 . Also, the communication control unit 201 transfers the acquired call information to the fastpath control unit 202 . Further, the communication control unit 201 transmits the acquired call information to the standby U-Plane server 20 (transfers the call information).

The fastpath control unit 202 is means for controlling the fastpath function implemented in the U-Plane server 20 . The fastpath control unit 202 compares the call information stored in the storage unit 204 with the acquired call information, and checks whether or not the same call information as the acquired call information exists in the storage unit 204 .

As a result of the comparison, if the same call information does not exist in the storage unit 204, the fastpath control unit 202 creates the above-described flow entry (information including information for specifying the flow and the transfer destination of the packet) based on the acquired call information. is generated, and the flow entry is stored in the storage unit 204 . The process of creating a flow entry from the call information by the fastpath control unit 202 and storing it in the storage unit 204 corresponds to the presetting process.

As a result of the comparison, if the same call information as the call information acquired from the communication control unit 201 is stored in the storage unit 204, the fastpath control unit 202 discards the acquired call information (performs special processing). do not have). This is because the fact that the same call information as the call information stored in storage unit 204 is obtained indicates that the corresponding flow entry has already been generated and stored in storage unit 204 .

The packet forwarding unit 203 is means for forwarding packets using fastpath technology. Specifically, the packet transfer unit 203 receives a packet transmitted from the user terminal 50 and processes the received packet according to the flow entry stored in the storage unit 204 .

Thus, the U-Plane server 20 has a "call information transfer function" and a "preset processing function" for fastpath as applications. That is, the call information transfer function is a function of transferring the call information received from the C-Plane server 10. FIG. The pre-setting processing function is a function for performing pre-processing necessary for communication (packet transfer) based on call information. The U-Plane server 20 uses a fast path as a communication function, holds the results of preprocessing, and performs communication transmission/reception processing.

The processing configurations of the C-Plane server 10, eNodeB 40, user terminal 50, etc. are obvious to those skilled in the art, and existing devices and the like can be used, so detailed description thereof will be omitted.

Next, operation of the communication system according to the first embodiment will be described. FIG. 4 is a sequence diagram illustrating an example of the operation of the communication system according to the first embodiment; Referring to FIG. 4, the operation of performing pre-processing (pre-setting) required for communication in the U-Plane server 20 by the active and standby servers will be described.

The C-Plane server 10 transmits call information to the active U-Plane server 20-1 (step S01).

The active U-Plane server 20-1 receives the call information (step S02).

The active U-Plane server 20-1 transfers the call information to the standby U-Plane server 20-2 (step S03).

The active U-Plane server 20-1 processes the call information (step S04). Specifically, the U-Plane server 20-1 generates a flow entry necessary for implementing the fastpath function from the call information. That is, the active U-Plane server 20-1 generates information (flow entry) for forwarding packets based on the call information acquired from the C-Plane server 10. FIG.

Thereafter, active U-Plane server 20-1 stores the result of processing the call information (result of pre-processing; flow entry) in storage unit 204 (step S05).

The standby U-Plane server 20-2 processes the call information transferred from the active U-Plane server 20-1 (step S06).

Thereafter, standby U-Plane server 20-2 stores the result of processing the call information (result of pre-processing; flow entry) in storage unit 204 (step S07).

The active U-Plane server 20-1 transfers the packet according to the flow entry stored in the storage unit 204 (step S08).

The process as described above is repeated each time a new call is made. The standby U-Plane server 20-2 acquires at least the transferred call information, and is configured to be able to use functions related to creating flow entries based on the call information and storing them in the storage unit 204. ing.

Consider a case where a failure occurs in the active U-Plane server 20-1. In the communication system according to the first embodiment, heartbeat signals are transmitted and received between the active and standby U-Plane servers 20 to monitor each other's life and death. When the U-Plane server 20-1 fails, the U-Plane server 20-2 detects the failure of the U-Plane server 20-1 (step S09). As described above, the U-Plane server 20-2 detects the occurrence of the failure by life-and-death monitoring using the heartbeat signal.

After that, the U-Plane server 20-2 performs system switching (step S10). Specifically, the U-Plane server 20-2 is activated as an active server. At that time, the U-Plane server 20-2, which becomes the new active system, changes the IP address. Specifically, the U-Plane server 20-2 uses the IP address previously used by the active U-Plane server 20-1 as the IP address for communicating with the C-Plane server 10. do.

As a result, the C-Plane server 10 can transmit call information to the U-Plane server 20-2 that has newly become the active system (step S02). In this way, the C-Plane server 10, when system switching occurs in a plurality of redundantly configured U-Plane servers 20, the standby U-Plane server 20 (newly operating U-Plane server 20). Send call information to the Plane server 20). That is, the U-Plane server 20-2, which becomes the new operating system, performs IP address replacement, so that the C-Plane server 10 can transmit call information without being aware of the system switching of the U-Plane server 20. can continue.

The U-Plane server 20-2 compares the acquired call information with the call information (the call information stored in the storage unit 204) acquired from the previously active U-Plane server 20-1 (step S11). ). If the two pieces of call information match, the U-Plane server 20-2 discards the call information (does not perform preprocessing). That is, the U-Plane server 20-2 discards the call information transmitted from the C-Plane server 10 when the call information acquired from the active system and the call information acquired from the C-Plane server 10 match.

The U-Plane server 20-2, which has newly become the active system, forwards the received packet according to the result of pre-processing (flow entry) that has already been set (step S12). Note that FIG. 4 describes that the U-Plane server 20-2 transfers the packet after receiving the call information from the C-Plane server 10. FIG. However, since the U-Plane server 20-2 has completed the preprocessing for packet transfer, the U-Plane server 20-2 does not wait for the reception of the call information and transfers the packet by the fast path. can be done. In other words, the U-Plane server 20-2, which has become a new operating system, can start packet transfer using the fastpath without the processes related to steps S02 and S11 shown in FIG.

In this way, the standby U-Plane server 20-2 holds information (flow entry) for packet transfer in advance before packet transfer (before transition to the active system), and when its own device transitions to the active system In this case, packet transfer is performed using the held information for packet transfer. As a result, even if system switching occurs due to a failure of the active server, etc., the pre-processing related to the fast path of the new active server has been completed, so user signals (user data, packets) communication can be resumed without delay at the same time as the input of

A hardware configuration of each device described in the above embodiment will be described.

[Hardware configuration]
FIG. 5 is a diagram showing an example of the hardware configuration of the U-Plane server 20. As shown in FIG. The U-Plane server 20 has a configuration illustrated in FIG. For example, the U-Plane server 20 includes a CPU (Central Processing Unit) 21, a memory 22, a communication interface NIC (Network Interface Card) 23, etc., which are interconnected by an internal bus.

However, the configuration shown in FIG. 5 is not meant to limit the hardware configuration of the U-Plane server 20 . The U-Plane server 20 may include hardware not shown. The number of CPUs, etc. included in the U-Plane server 20 is not limited to the example in FIG.

The memory 22 is a RAM (Random Access Memory), a ROM (Read Only Memory), an auxiliary storage device (such as a hard disk), or the like.

The functions of the U-Plane server 20 are implemented by modules that execute the processes described above. The module is implemented by the CPU 21 executing a program stored in the memory 22, for example. Also, the program can be downloaded via a network or updated using a storage medium storing the program. Furthermore, the processing module may be realized by a semiconductor chip. In other words, the functions performed by the processing modules may be realized by some kind of hardware or software executed using hardware.

Since the hardware configuration of the C-Plane server 10 etc. is obvious to those skilled in the art, the description thereof will be omitted.

As described above, in the U-Plane server 20 according to the first embodiment, the call information transmitted to the active server is transferred to the standby server, and pre-processing necessary for Fastpass is performed by the standby server. Let it be completed on the other side as well. As a result, even when switching from the active system to the standby system in the redundant configuration occurs, communication can be continued without delay.

[Modification]
Note that the configuration of the communication system described in the above embodiment is an example, and is not intended to limit the configuration of the system. For example, FIG. 2 shows a redundant configuration using two U-Plane servers 20, but a redundant configuration using three or more U-Plane servers 20 may be employed. Even in this case, the active U-Plane server 20 transfers the “call information” to all the standby U-Plane servers 20 .

In the above-described embodiment, the fast path was explained as an example of a communication method that requires presetting, but it goes without saying that other communication methods may also be used. That is, the disclosure of the present application can be applied to a server in which a communication method requiring presetting is implemented.

Although the industrial applicability of the present invention is clear from the above description, the present invention can be suitably applied to real-time communication such as VoIP (Voice over Internet Protocol).

Some or all of the above embodiments may also be described in the following additional remarks, but are not limited to the following.
[Appendix 1]
It is as the communication system concerning the above-mentioned 1st viewpoint.
[Appendix 2]
Preferably, the communication system according to appendix 1, wherein the plurality of communication devices perform packet transfer using a communication method that requires prior setting before execution of packet transfer.
[Appendix 3]
The standby-system communication device holds the generated information for packet transfer, and when the self-device transitions to the active-system communication device, uses the held information for packet transfer to perform packet transfer. A communication system, preferably according to clauses 1 or 2, with forwarding.
[Appendix 4]
Preferably, the communication system according to any one of Appendices 1 to 3, wherein the active communication device generates information for forwarding the packet based on call information acquired from the control device.
[Appendix 5]
Preferably, according to any one of Appendices 1 to 4, the control device transmits call information to the standby communication device when system switching occurs in the redundantly configured plurality of communication devices. communication system.
[Appendix 6]
Preferably, the communication system according to appendix 5, wherein the standby communication device discards the call information transmitted from the control device when the self device transitions to the active communication device.
[Appendix 7]
Preferably, the standby communication device discards the call information transmitted from the control device when the call information acquired from the active communication device and the call information acquired from the control device match. 7. Communication system according to 6.
[Appendix 8]
8. The communication system, preferably according to any one of appendices 1 to 7, wherein the communication system requiring pre-configuration is Fastpath.
[Appendix 9]
Preferably, the information for forwarding the packet includes information for identifying a flow and information regarding an output destination of packets belonging to the identified flow. Communication system as described.
[Appendix 10]
This is the same as the communication device according to the second aspect described above.
[Appendix 11]
This is the communication method according to the third aspect described above.
[Appendix 12]
It is as the program related to the above-mentioned fourth viewpoint.
It should be noted that the modes of supplementary notes 10 to 12 can be developed into the modes of supplementary notes 2 to 9 in the same way as the form of supplementary note 1.

The disclosures of the cited patent documents are incorporated herein by reference. Within the framework of the full disclosure of the present invention (including the scope of claims), modifications and adjustments of the embodiments and examples are possible based on the basic technical concept thereof. Also, various combinations or selections of various disclosure elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) within the framework of the full disclosure of the present invention (including partial deletion) is possible. That is, the present invention naturally includes various variations and modifications that can be made by those skilled in the art according to the entire disclosure including claims and technical ideas. In particular, any numerical range recited herein should be construed as specifically recited for any numerical value or subrange within that range, even if not otherwise stated.

10 C-Plane servers 20, 20-1, 20-2 U-Plane server 21 CPU
22 memory 23 NIC
30 EPCs
40 eNodeBs
50 User terminal 101 Communication device 102 Control device 201 Communication control unit 202 Fast path control unit 203 Packet transfer unit 204 Storage unit

Claims (9)

a plurality of redundantly configured communication devices;
a control device that transmits call information to an active communication device among the plurality of communication devices;
including
The active communication device transfers the received call information to a standby communication device among the plurality of communication devices,
The communication system, wherein the standby-system communication device generates a flow entry based on the transferred call information before a failure occurs in the active-system communication device . 2. The communication system according to claim 1, wherein said plurality of communication devices perform packet transfer using a communication method that requires prior setting before execution of packet transfer. The standby-system communication device holds the generated information for packet transfer, and when the self-device transitions to the active-system communication device, uses the held information for packet transfer to perform packet transfer. 3. A communication system according to claim 1 or 2, wherein the transmission is performed. The communication system according to any one of claims 1 to 3, wherein said active communication device generates said flow entry based on call information acquired from said control device. 5. The control device according to any one of claims 1 to 4, wherein when system switching occurs in the redundantly configured communication devices, the control device transmits call information to the standby communication device. communication system. 6. When the call information acquired from the active communication device matches the call information acquired from the control device, the standby communication device discards the call information transmitted from the control device. a communication system as described in . When the own device is an active device, transfer the call information acquired from the control device to another standby device,
A communication device that generates a flow entry before a failure occurs in the active communication device based on the transferred call information when the own device is a standby device. a plurality of redundantly configured communication devices;
a control device that transmits call information to an active communication device among the plurality of communication devices;
In a communication system comprising
The active communication device transfers the received call information to a standby communication device among the plurality of communication devices,
The communication method, wherein the standby communication device generates a flow entry based on the transferred call information before a failure occurs in the active communication device . a process of transferring call information acquired from the control device to another standby device when the own device is an active device;
a process of generating a flow entry before a failure occurs in the active communication device based on the transferred call information when the own device is a standby device;
A program that causes a computer installed in a communication device to execute

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