JP7747199B2 - COMMUNICATION CONTROL DEVICE, COMMUNICATION CONTROL METHOD, AND COMMUNICATION CONTROL PROGRAM - Google Patents

Description

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

In carrier networks, edge routers accommodating user terminals ("user terminals" or "terminals" as appropriate) are switched ("maintenance relocation" as appropriate) for maintenance purposes at the convenience of the telecommunications carrier. When switching edge routers, the configuration information ("user configuration" as appropriate) of the accommodating user is deleted from the edge router from which the switch is made ("source edge router" as appropriate), and the same information is then entered into the edge router to which the switch is made ("destination edge router" as appropriate). For security purposes, uRPF (unicast Reverse Path Forwarding) may be applied to edge routers in carrier networks, and its application is recommended by the IETF (Internet Engineering Task Force), a standardization organization for Internet-related technologies.

In a conventional technology, when performing maintenance and relocation of edge routers in a carrier network, a technology has been proposed in which the edge control system works in conjunction with a DHCP (Dynamic Host Configuration Protocol) server system to complete the switchover in a short time while minimizing the impact on user communications services.

Nishiguchi et al., "Edge router maintenance relocation method to minimize communication interruptions," Proceedings of the 2021 Institute of Electronics, Information and Communication Engineers General Conference, B-6-68, Mar. 2021.

However, the above-mentioned conventional technology leaves room for improvement when it comes to maintenance and relocation of edge routers in carrier networks. For example, conventional technology requires adding functionality to both the edge control system and the DHCP server system, which is difficult to do when the respective devices are owned by different telecommunications carriers.

In order to solve the above-mentioned problems and achieve the objectives, the communication control device of the present invention is characterized by comprising: an acquisition unit that acquires switching information regarding the switching of an edge router that accommodates a user's terminal; a setting unit that, when the acquisition unit acquires the switching information, configures the source edge router to block DHCP packets and disable multicast communication; an input unit that, when the configuration unit configures the blocking of DHCP packets and the disablement of multicast communication, inputs the user's configuration information to the destination edge router; an instruction unit that, based on the switching information, instructs a pseudo-DHCP server, which is a virtual server, to induce the terminal to re-acquire an IP (Internet Protocol) address; a reception unit that receives a notification from the pseudo-DHCP server that the instruction to induce re-acquisition has been received; and a deletion unit that, when a predetermined time has elapsed since the notification of the instruction to induce re-acquisition was received, deletes the user's configuration information held by the source edge router.

Furthermore, the communication control method of the present invention is a communication control method executed by a communication control device, and is characterized by including: an acquisition step of acquiring switching information regarding the switching of an edge router accommodating a user's terminal; a configuration step of configuring the source edge router to block DHCP packets and cancel multicast communication when the acquisition step acquires the switching information; an input step of inputting the user's configuration information to the destination edge router when the setting step configures blocking of DHCP packets and cancellation of multicast communication; an instruction step of instructing a pseudo-DHCP server, which is a virtual server, to induce the terminal to re-acquire an IP address based on the switching information; an acceptance step of accepting a specified notification from the pseudo-DHCP server based on the instruction to induce re-acquisition; and a deletion step of deleting the user's configuration information held by the source edge router when a specified time has elapsed since the time the notification of the instruction to induce re-acquisition was accepted.

The communication control program of the present invention is characterized in that it causes a computer to execute the following steps: an acquisition procedure for acquiring switching information regarding the switching of an edge router that accommodates a user's terminal; a configuration procedure for configuring the source edge router to block DHCP packets and disable multicast communication when the acquisition procedure acquires the switching information; an input procedure for inputting the user's configuration information to the destination edge router when the configuration procedure configures the blocking of DHCP packets and the disablement of multicast communication; an instruction procedure for instructing a pseudo-DHCP server, which is a virtual server, to induce the terminal to re-acquire an IP address based on the switching information; an acceptance procedure for accepting a specified notification from the pseudo-DHCP server based on the instruction to induce re-acquisition; and a deletion procedure for deleting the user's configuration information held by the source edge router when a specified time has elapsed since the time the notification of the instruction to induce re-acquisition was accepted.

The present invention enables maintenance relocation of edge routers to be performed effectively.

FIG. 1 is a diagram illustrating an example of the configuration of an edge control system according to the first embodiment. FIG. 2 is a sequence diagram showing the flow of conventional edge control processing. FIG. 3 is a block diagram illustrating an example of the configuration of the edge control device according to the first embodiment. FIG. 4 is a diagram showing a specific example of the reacquisition prompt instruction method according to the first embodiment. FIG. 5 is a sequence diagram showing an example of the flow of edge control processing 1 according to the first embodiment. FIG. 6 is a sequence diagram showing an example of the flow of edge control processing 2 according to the first embodiment. FIG. 7 is a sequence diagram showing an example of the flow of edge control processing 3 according to the first embodiment. FIG. 8 is a diagram illustrating a computer that executes a program.

The following describes in detail, with reference to the drawings, embodiments of an edge control device (sometimes referred to as a "communication control device"), an edge control method (sometimes referred to as a "communication control method"), and an edge control program (sometimes referred to as a "communication control program") according to the present invention. Note that the present invention is not limited to the embodiments described below.

First Embodiment
Below, we will explain the configuration of the edge control system related to the first embodiment, the configuration of the edge control device, a specific example of an address re-acquisition induction instruction method, and the overall flow of the edge control processing, and finally explain the effects of the first embodiment.

1. Configuration of the edge control system 100
The configuration of the edge control system 100 according to the first embodiment will be described in detail using Fig. 1. Fig. 1 is a diagram showing an example of the configuration of the edge control system 100 according to the first embodiment. Below, an example of the overall configuration of the edge control system 100 will be shown, and then each process will be described.

1-1. Example of the overall configuration of the edge control system 100
The edge control system 100 includes an edge control device 10, edge routers 20 (20A, 20B), user terminals 30 (30A, 30B, 30C, 30D), a DHCP server 40, a pseudo-DHCP server 40V, user DBs (databases) 50 (50A, 50B), and a communication network 60 consisting of a core network 60A and an access network 60B. Here, the edge control device 10, the edge router 20, the user terminals 30, the DHCP server 40, the pseudo-DHCP server 40V, and the user DB 50 are communicatively connected via the communication network 60 or a predetermined communication network (not shown) by wire or wirelessly. Note that the edge control system 100 shown in FIG. 1 may include multiple edge control devices 10 and multiple DHCP servers 40 or pseudo-DHCP servers 40V.

(1-1-1. Edge control device 10)
The edge control device 10 has a user DB 50A that manages user information, and inputs user configuration 21 such as a user SO (Service Order) into the edge router 20 (see FIG. 1 (1)). In FIG. 1, the edge control device 10 inputs the user configuration 21 into the edge router 20B, but it can also input the user configuration 21 into the edge router 20A. In addition, a link interface is introduced between the edge control device 10 and the DHCP server 40, allowing the edge control device 10 and the DHCP server 40 to send and receive various information to and from each other (see FIG. 1 (2)).

If an interface for linking is not installed between the edge control device 10 and the DHCP server 40, or if the linking interface only links a portion of the user terminals 30, the edge control device 10 executes processing using a pseudo-DHCP server 40V. Details of the edge control processing by the edge control device 10 will be described later in [3. Flow of Edge Control Processing]. The edge control device 10 can also construct a pseudo-DHCP server 40V.

(1-1-2. DHCP Server 40)
The DHCP server 40 assigns an address to the user terminal 30 (see FIG. 1 (3)). The DHCP server 40 also holds a DB 40B that manages user information, and communicates with the user terminal 30 after identifying the user (see FIG. 1 (4)). The DHCP server 40 refers to the IP address, DHCP option values, etc. when identifying the user.

(1-1-3. Edge Router 20)
The edge router 20 applies uRPF for security reasons (see (5) in FIG. 1). The edge router 20 also relays DHCP packets (see (6) in FIG. 1). Each edge router belongs to the same broadcast domain.

(1-1-4. Pseudo DHCP server 40V)
When the linking interface is not supported, the pseudo DHCP server 40V links with the edge control device 10 and the DHCP server 40 (see FIG. 1 (7)). The pseudo DHCP server 40V is built, for example, on the resources of the edge control device 10 or on a cloud service.

1-2. Processing of the Edge Control System 100
The following describes the processes of the edge control system 100: DHCP blocking process, pseudo DHCP server cooperation process, and edge router setting deletion process. Note that the following processes can be executed in a different order. Also, some of the following processes may be omitted.

(1-2-1. DHCP blocking process)
First, the edge control device 10 receives a switching execution instruction from a maintenance person M (not shown) who will be performing the maintenance relocation (switching execution instruction reception process), sets a DHCP blocking filter for the switching source edge router 20A (DHCP blocking filter setting process), and issues an RA (Router Advertisement) suppression command to delete the multicast setting (multicast setting deletion process).The edge control device 10 also inputs user configuration 21 such as user SO to the switching destination edge router 20B (user configuration input process).

As described above, the edge control device 10 can perform DHCP blocking processing by performing switching execution instruction reception processing, DHCP blocking filter setting processing, multicast setting deletion processing, and user configuration input processing.

(1-2-2. Pseudo DHCP Server Collaboration Processing)
Below, pseudo DHCP server cooperation methods 1 to 3 executed by the edge control device 10 will be explained, and the IP switching process executed by the edge router 20, the user terminal 30 and the DHCP server 40 will be explained.

(1-2-2-1. Collaboration method 1)
If a linking interface is not introduced between the edge control device 10 and the DHCP server, the edge control device 10 transmits an instruction to the pseudo DHCP server 40V to induce re-acquisition (reconfigure) of the IP address from the edge control device 10 (re-acquisition inducement instruction processing).The edge control device 10 then receives a completion notification transmitted from the pseudo DHCP server 40V that has received the instruction (completion notification reception processing).

As described above, in pseudo-DHCP server collaboration method 1, the edge control device 10 can execute pseudo-DHCP server collaboration processing by performing a re-acquisition inducement instruction process and a completion notification reception process. Furthermore, if a collaboration interface is introduced between the edge control device 10 and the DHCP server 40, or if a collaboration interface that was not initially introduced is introduced, the edge control device 10 executes a re-acquisition inducement instruction process for the DHCP server 40 and receives a re-acquisition inducement completion notification from the DHCP server 40 (re-acquisition inducement completion notification reception process), similar to the technology shown in Non-Patent Document 1.

(1-2-2-2. Collaboration method 2)
When the collaboration interface targets some user terminals 30 for collaboration, the edge control device 10 executes re-acquisition inducement instruction processing on the DHCP server 40 for the user terminals 30 that are targets for collaboration, and executes re-acquisition inducement instruction processing on the pseudo DHCP server 40V for the user terminals 30 that are not targets for collaboration. Then, the edge control device 10 executes re-acquisition inducement completion notification acceptance processing from the DHCP server 40 for the user terminals 30 that are targets for collaboration, and executes completion notification acceptance processing from the pseudo DHCP server 40V for the user terminals 30 that are not targets for collaboration.

As described above, in pseudo-DHCP server collaboration method 2, the edge control device 10 can execute DHCP server collaboration processing for the user terminal 30 that is the collaboration target by issuing a re-acquisition invitation instruction to the DHCP server 40 and receiving a re-acquisition invitation completion notification from the DHCP server 40. On the other hand, for the user terminal 30 that is not the collaboration target, the edge control device 10 can execute pseudo-DHCP server collaboration processing by issuing a re-acquisition invitation instruction to the pseudo-DHCP server 40V and receiving a completion notification from the pseudo-DHCP server 40V.

(1-2-2-3. Collaboration method 3)
When only an existing interface is introduced between the edge control device 10 and the DHCP server 40, the edge control device 10 executes a re-acquisition inducement instruction process to the pseudo DHCP server 40V. Next, the pseudo DHCP server 40V converts the re-acquisition inducement instruction received from the edge control device 10 into a format that the existing interface can support, and executes a re-acquisition inducement instruction process to the DHCP server 40. Next, the pseudo DHCP server 40V executes a re-acquisition inducement completion notification reception process from the DHCP server 40, and converts the re-acquisition completion notification received from the DHCP server 40 into a format that the existing interface can support. Then, the edge control device 10 executes a re-acquisition inducement completion reception process from the pseudo DHCP server 40V.

As described above, in pseudo-DHCP server collaboration method 3, the edge control device 10 can perform pseudo-DHCP server collaboration processing by issuing a re-acquisition inducement instruction process to the DHCP server 40 via the pseudo-DHCP server 40V and receiving a re-acquisition inducement completion notification process from the DHCP server 40 via the pseudo-DHCP server 40V.

(1-2-2-4. IP switching process)
In the pseudo-DHCP server cooperation methods 1 to 3 described above, if the edge control device 10 does not issue a re-acquisition inducement instruction to the DHCP server 40, the following IP switching process is executed. First, the edge router 20, user terminal 30, and DHCP server 40 start a user communication switching process in response to a re-acquisition inducement instruction from the maintenance person M to the DHCP server 40 or a DHCP renew from the user terminal 30. The switching process is then executed for all user terminals 30, and the IP switching process is completed. Then, when the IP switching process is completed, the DHCP server 40 sends a re-acquisition inducement completion notification to the maintenance person M.

(1-2-3. Edge router setting deletion process)
After receiving a completion notification from the pseudo DHCP server 40V and after a certain period of time has elapsed, the edge control device 10 deletes the user configuration 21, such as the user SO, held by the source edge router 20A. That is, after the IP switching process for user communication between the edge router 20, the user terminal 30, and the DHCP server 40 is completed, the edge control device 10 deletes the user configuration 21 held by the source edge router 20A (user configuration deletion process). At this time, the edge control device 10 deletes the aggregated address setting held by the source edge router 20A (aggregated address deletion process) and sets an aggregated address for the destination edge router 20B (aggregated address setting process). The edge control device 10 can also check the progress with the maintenance person M as necessary (progress confirmation process).

As described above, the edge control device 10 can execute the edge router setting deletion process through the user configuration deletion process, the aggregate address deletion process, the aggregate address setting process, and the progress status confirmation process. Finally, the edge control device 10 sends a switching completion notification to the maintenance person M (switching completion notification process).

1-3. Effects of the edge control system 100
Below, the edge control process and improvements that have been made using the collaboration interface described in Non-Patent Document 1 will be explained in order, and then the effects of the edge control system 100 will be described in detail.

(1-3-1. Conventional Edge Control Processing)
Using FIG. 2, an edge control process incorporating the collaboration interface described in Non-Patent Document 1 will be described. FIG. 2 is a sequence diagram showing the flow of conventional edge control process. The following describes the switching execution instruction process, DHCP blocking process, IP switching process, setting deletion process, and switching completion notification process in that order. Note that FIG. 2 uses an example of DHCPv6 (Dynamic Host Configuration Protocol version 6) as the communication method, but DHCPv4 (Dynamic Host Configuration Protocol version 4) or the like may also be used. In addition, in the example of FIG. 2, a collaboration interface is introduced between the edge control device 10 and the DHCP server 40. Here, the collaboration interface enables the edge control device 10 to issue a re-acquisition inducement instruction to the DHCP server 40, enables the DHCP server 40 to notify the edge control device 10 of the completion of the re-acquisition inducement, and enables the edge control device 10 and the DHCP server 40 to acquire lease timer information from each other.

(1-3-1-1. Switching execution instruction processing)
A maintenance technician M who performs the maintenance relocation transmits a switching execution instruction including switching information to the switching source edge router 20A, which is performing user communication (step S101) with the user terminals 30 (30A, 30B, 30C, 30D) (step S102). Here, users 1 to 4 use user terminals 30A to 30D, respectively. User 1's user terminal 30A and user 2's user terminal 30B belong to VNE (Virtual Network Enabler) #a1, and user 30C of user 3 and user 4's user terminal 30D belong to VNE #b1. Note that "#a1" and "#b1" indicate aggregate addresses.

(1-3-1-2. DHCP blocking process)
The edge control device 10 sets a DHCPv6 blocking filter for the source edge router 20A to block DHCPv6 for users 1 and 2 (step S103), and issues an RA suppression command to delete the multicast setting (step S104). The edge control device 10 also inputs user configurations 21, such as user SO, to the destination edge router 20B (step S105). Similarly, the edge control device 10 sets a DHCPv6 blocking filter for the source edge router 20A to block DHCPv6 for users 3 and 4 (step S106), inputs an RA suppression command (step S107), and inputs user configurations 21, such as user SO, to the destination edge router 20B (step S108). As described above, even if the maintenance operator M issues a switching execution instruction only once, the edge control device 10 divides and executes the DHCP blocking process for each set unit (e.g., aggregated address).

As described above, by blocking DHCP and deleting multicast settings in advance, there are no adverse effects even when the user configuration 21 is applied to multiple edge routers. For example, the above process prevents network bandwidth congestion and unexpected terminal behavior due to multiplexed distribution of video and other data from multiple edge routers 20 to terminals.

(1-3-1-3. IP switching process)
To switch IPv6 addresses for users 1 to 4, the edge control device 10 transmits a DHCPv6 re-acquisition invitation instruction to the DHCP server 40 in which the linking interface is installed (step S109). Next, the DHCP server 40 transmits a DHCPv6 re-acquisition invitation to the user terminals 30A to 30D (step S110). Subsequently, the user terminals 30A to 30D transmit DHCPv6 updates to the source edge router 20A and the destination edge router 20B to re-acquire addresses. At this time, the destination edge router 20B relays the DHCP packets, updates the DHCP binding table of the destination edge router 20B, and re-assigns the IP addresses, thereby completing the switching of the user communication path (step S111). The DHCP server 40 then transmits a DHCPv6 re-acquisition invitation completion notification to the edge control device 10 in which the linking interface is installed (step S112).

(1-3-1-4. Setting deletion process)
The edge control device 10 deletes the user configuration 21 of the user SO etc. held by the source edge router 20A in order to delete the settings of users 1 to 4 (step S113). At this time, the edge control device 10 deletes the settings of the aggregation addresses ("#a1", "#b1") held by the source edge router 20A (step S114), and sets the aggregation addresses ("#a1", "#b1") in the destination edge router 20B (step S115).

(1-3-1-5. Switching completion notification processing)
When the setting deletion process is completed, the edge control device 10 transmits a switching completion notification to the maintenance person M who will be performing the maintenance relocation (step S116).

(1-3-2. Improvements in conventional edge control processing)
The following describes improvements to the edge control process that introduces the linkage interface shown in Non-Patent Document 1, with reference to Fig. 2. The above edge control process has the following three improvements.

(1-3-2-1. Improvement point 1)
As a first improvement, the above technology requires not only the addition of functions to the edge control device 10 but also the addition of a cooperation interface that allows the DHCP server 40 to receive instructions and notify completion. That is, in the example of Fig. 2, it is necessary to add a cooperation interface for executing the re-acquisition inducement instruction process in step S109 and the re-acquisition inducement completion notification process in step S112.

(1-3-2-2. Improvement point 2)
As a second improvement, the above technology requires the development and release of multiple systems, which can lead to a concentration of development periods, a longer development period due to interface adjustments between systems, and more complicated and difficult release adjustments due to an increase in the number of systems to be released. That is, in the example of Fig. 2, a burden can arise due to the development and release of an edge control system including the edge control device 10 and a DHCP server system including the DHCP server 40.

(1-3-2-3. Improvement point 3)
As a third improvement, in the above technology, when the edge control device 10 and the DHCP server 40 are managed by different telecommunications carriers, even if it is decided to install a function in the edge control device 10, it is not possible to confirm the installation of the function in the DHCP server 40. That is, in the example of Fig. 2, it may be difficult to install a linkage interface between the edge control system including the edge control device 10 and the DHCP server system including the DHCP server 40.

(1-3-3. Overview of edge control system 100)
In the edge control system 100, the edge control device 10 acquires switching information regarding the switching of the edge router 20 that accommodates the user terminal 30, sets the source edge router 20A to block DHCP packets and disable multicast communication, inputs user setting information (user config) to the destination edge router 20B, and based on the switching information, instructs the pseudo-DHCP server 40V, which is a virtual server, to induce the user terminal 30 to re-acquire an IP address, accepts a completion notification from the pseudo-DHCP server indicating that the instruction to induce re-acquisition has been received, and deletes the user config 21 held by the source edge router 20A if a predetermined time has elapsed since the completion notification was received.

In addition, in the edge control system 100, when the edge control device 10 is responsively connected to the DHCP server 40, which is a physical server, via a specified interface, it instructs the DHCP server 40 to induce re-acquisition, receives a notification of completion of the re-acquisition inducement from the DHCP server, and deletes the user configuration 21 held by the source edge router 20A.

In addition, in the edge control system 100, the edge control device 10 instructs the DHCP server 40 to induce re-acquisition for each specified unit (e.g., device, LAG, user) at specified time intervals, instructing the DHCP server 40 to induce re-acquisition for units that the DHCP server 40 can handle, and instructing the pseudo-DHCP server 40V to induce re-acquisition for units that the DHCP server 40 cannot handle.

In addition, in the edge control system 100, the edge control device 10 sends a re-acquisition inducement instruction to the DHCP server 40, which has been converted into a format that can be handled by the pseudo-DHCP server 40V, receives a completion notification from the DHCP server 40 of the re-acquisition inducement converted into a format that can be handled by the pseudo-DHCP server 40V, and deletes the user configuration 21 held by the source edge router 20A.

(1-3-4. Effects of the edge control system 100)
As described above, the edge control system 100 enables effective switching by introducing a corresponding function into the edge control device 10, without introducing a corresponding function into the DHCP server 40. In other words, even if a linkage interface is not introduced between the edge control device 10 and the DHCP server 40, the edge control system 100 can complete switching in a short time while minimizing the impact on user communications services by using the pseudo DHCP server 40V.

Furthermore, after introducing a corresponding function into the DHCP server 40, the edge control system 100 becomes capable of advanced switching without adding any further functions to the edge control device 10. In other words, when a collaboration interface is introduced between the edge control device 10 and the DHCP server 40, the edge control system 100 can use the DHCP server 40 to more effectively minimize the impact on user communications services and complete switching in a short time.

The edge control system 100 also enables effective switching even when only partial support functions are introduced into the DHCP server 40. In other words, when an interface that enables collaboration with some users is introduced between the edge control device 10 and the DHCP server 40, the edge control system 100 uses the pseudo DHCP server 40V and the DHCP server 40 in combination, enabling switching to be completed in a short time while minimizing the impact on user communications.

In addition, the edge control system 100 enables effective switching without introducing a corresponding function into the DHCP server 40. In other words, when only an existing interface is introduced between the edge control device 10 and the DHCP server 40, the edge control system 100 converts the notification format between the pseudo DHCP server 40V and the DHCP server 40, thereby enabling switching to be completed in a short time while minimizing the impact on user communications services.

Furthermore, before the introduction of the corresponding function into the DHCP server 40, the edge control system 100 may result in an increase in the amount of work required by the maintenance personnel M during operation compared to conventional technology, or the cost of the increased work required by the maintenance personnel M may be high depending on the circumstances of the telecommunications carrier. However, the system also makes it possible to operate in a way that avoids an increase in the amount of work required by the maintenance personnel M in exchange for accepting a longer time until the user communication path switching is completed.

As described above, the edge control system 100, by introducing a pseudo-DHCP server 40V collaboration function into the edge control device 10, enables switching to be completed in a short time while minimizing the impact on user communications services, regardless of the status of function introduction into the DHCP server 40.

2. Configuration of edge control device 10
The functional configuration of the edge control device 10 according to the first embodiment will be described in detail below. An example of the configuration of the edge control device 10 according to the first embodiment and a specific example of a reacquisition inducement instruction method will be described below.

2-1. Example of the configuration of the edge control device 10
An example of the configuration of the edge control device 10 according to the first embodiment will be described in detail with reference to Fig. 3. Fig. 3 is a block diagram showing an example of the configuration of the edge control device 10 according to the first embodiment. The edge control device 10 has an input unit 11, an output unit 12, a communication unit 13, a storage unit 14, and a control unit 15.

(2-1-1. Input unit 11)
The input unit 11 controls input of various information to the edge control device 10. The input unit 11 is, for example, a mouse or a keyboard, and receives input of setting information and the like to the edge control device 10.

(2-1-2. Output unit 12)
The output unit 12 controls the output of various information from the edge control device 10. The output unit 12 is, for example, a display, and outputs setting information stored in the edge control device 10.

(2-1-3. Communication unit 13)
The communication unit 13 controls data communication with other devices. For example, the communication unit 13 performs data communication with each communication device. The communication unit 13 can also perform data communication with an operator's terminal (not shown).

(2-1-4. Storage unit 14)
The storage unit 14 stores various information referenced when the control unit 15 operates and various information acquired when the control unit 15 operates. Here, the storage unit 14 is, for example, a semiconductor memory element such as a random access memory (RAM) or a flash memory, or a storage device such as a hard disk or an optical disk. Note that, in the example of Fig. 3, the storage unit 14 is installed inside the edge control device 10, but it may be installed outside the edge control device 10, or multiple storage units may be installed.

(2-1-5. Control unit 15)
The control unit 15 is responsible for overall control of the edge control device 10. The control unit 15 has an edge control unit 151 and a pseudo server control unit 152. Here, the control unit 15 is, for example, an electronic circuit such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit), or an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

(2-1-5-1. Edge control unit 151)
The edge control unit 151 includes an acquisition unit 151a, a setting unit 151b, an input unit 151c, an instruction unit 151d, a reception unit 151e, and a deletion unit 151f.

(Acquisition unit 151a)
The acquiring unit 151a acquires switching information related to switching of the edge router 20A that accommodates the user terminal 30. For example, the acquiring unit 151a acquires, as the switching information, information on the switching source edge router 20A, information on the accommodated user terminal 30, information on the switching destination edge router 20B, the purpose of switching of the edge router 20, the scheduled switching start time, the scheduled switching end time, etc. Meanwhile, the acquiring unit 151a may store the acquired switching information in the storage unit 14.

(Setting section 151b)
When the acquiring unit 151a acquires switching information, the setting unit 151b sets the source edge router 20A to block DHCP packets and cancel multicast communication. For example, when the setting unit 151b acquires information about maintenance relocation of the source edge router 20A as the purpose of switching the edge router 20, the setting unit 151b sequentially sets the source edge router 20A to block DHCP packets and cancel multicast distribution.

(Insertion part 151c)
When the setting unit 151b sets blocking of DHCP packets and cancellation of multicast communication, the input unit 151c inputs user setting information to the switching destination edge router 20B. For example, when the setting to block DHCP packets and the setting to cancel multicast distribution are performed on the switching source edge router 20A that is being relocated for maintenance, the input unit 151c inputs information on individual user transfer settings, such as IP address settings, VLAN (Virtual Local Area Network), and ACL (Access Control List), to the switching destination edge router 20B that is being relocated for maintenance.

(Instruction unit 151d)
Based on the switching information, the instruction unit 151d instructs the pseudo DHCP server 40V to induce the user terminal 30 to re-acquire an IP address. Based on the switching information, the instruction unit 151d also instructs the DHCP server 40 to induce the user terminal 30 to re-acquire an IP address. For example, the instruction unit 151d instructs the user terminal 30 to induce the user terminal 30 to re-acquire an IP address for each predetermined unit at predetermined time intervals. The instruction unit 151d also instructs the user terminal 30 to induce the user terminal 30 to re-acquire an IP address for each device, LAG, or user. Note that re-acquisition inducement instruction processes using different instruction methods by the instruction unit 151d will be described later in [2-2. Re-acquisition inducement instruction method].

When the instruction unit 151d is connected to the DHCP server 40, which is a physical server, via a specified interface in a manner that allows it to function, it instructs the DHCP server 40 to induce re-acquisition. Furthermore, the instruction unit 151d instructs the DHCP server 40 to induce re-acquisition for specified units that the DHCP server 40 can handle. Furthermore, the instruction unit 151d instructs the pseudo-DHCP server 40V to induce re-acquisition for specified units that the DHCP server 40 cannot handle. Furthermore, the instruction unit 151d transmits to the DHCP server 40 an instruction to induce re-acquisition that has been converted into a form that can be handled by the pseudo-DHCP server 40V. The re-acquisition inducement instruction process by the instruction unit 151d using a different collaboration method will be described later in [3. Flow of Edge Control Processing].

(Reception unit 151e)
The reception unit 151e receives a notification from the pseudo DHCP server 40V that an instruction to induce re-acquisition of an IP address has been received. The reception unit 151e also receives a notification from the DHCP server 40 that the user terminal 30 has completed inducing the re-acquisition of an IP address. For example, when the DHCP server 40 transmits a DHCP re-acquisition invitation to the user terminal 30, the reception unit 151e receives a notification that the re-acquisition invitation has been completed, which is transmitted from the DHCP server 40 to the edge control device 10. The reception unit 151e also receives a notification from the DHCP server 40 that the re-acquisition invitation has been completed, which has been converted into a format that can be handled by the pseudo DHCP server 40V.

(Deletion unit 151f)
The deletion unit 151f deletes the user setting information held by the switching source edge router 20A when a predetermined time has elapsed since the time when the notification that an instruction to induce re-acquisition of an IP address was received was received. Furthermore, the deletion unit 151f deletes the user setting information held by the switching source edge router 20A when the reception unit 151e receives a notification that the induction of re-acquisition of an IP address by the user terminal 30 has been completed. For example, the deletion unit 151f deletes information about individual user forwarding settings such as the IP address setting, VLAN, and ACL of the user terminal 30 that are stored in the switching source edge router 20A that is being relocated for maintenance.

(2-1-5-2. Pseudo server control unit 152)
The pseudo server control unit 152 includes a construction unit 152a.

(Construction unit 152a)
The construction unit 152a can construct a pseudo DHCP server 40V, which is a virtual server. For example, the construction unit 152a constructs the pseudo DHCP server 40V on the resources of the edge control device 10. The construction unit 152a can also be constructed on an information processing device or a cloud service other than the edge control device 10. In this case, the construction unit 152a constructs a pseudo DHCP server 40V that can receive an invitation to re-acquire an IP address sent by the instruction unit 151d and can transmit to the reception unit 151e a notification that the instruction to induce re-acquisition of an IP address has been received.

[2-2. Reacquisition Inducement Instruction Method]
The reacquisition prompt instruction method according to the first embodiment will be described in detail with reference to Fig. 4. Fig. 4 is a diagram showing a specific example of the reacquisition prompt instruction method according to the first embodiment. Below, the instruction message generation process performed prior to the reacquisition prompt instruction process will be described, and then three types of instruction methods and their advantages will be described.

(2-2-1. Instruction Message Generation Process)
First, the edge control device 10 acquires information about users involved in the maintenance relocation from the user DB 50A. At this time, the edge control device 10 acquires user identifiers {user identifier 1, user identifier 2, ... user identifier N} corresponding to N users as user information, and generates a re-acquisition prompt instruction message based on the user identifiers in the following manner. Note that the setting related to the method of the re-acquisition prompt instruction message can be changed statically or dynamically.

(2-2-2. Instruction method 1)
In instruction method 1, the edge control device 10 transmits an instruction message including one user per message to the DHCP server 40. In the example of instruction method 1 in Fig. 4, the edge control device 10 transmits three instruction messages corresponding to user 1, user 2, and user 3. The time interval between transmissions of each message can be set arbitrarily (see instruction method 1 in Fig. 4). For example, the edge control device 10 transmits an instruction message using instruction method 1 when targeting individual users or when leveling the flow rate of reacquired packets to the L2 section.

(2-2-3. Instruction method 2)
In instruction method 2, the edge control device 10 transmits an instruction message including multiple users per message to the DHCP server 40. In the example of instruction method 2 in Fig. 4, the edge control device 10 transmits one instruction message including all of {user 1, user 2, user 3, ...} (see instruction method 2 in Fig. 4). For example, in order to reduce the load on the edge control device 10, when instructing multiple target users at once, the edge control device 10 transmits an instruction message using instruction method 2.

(2-2-4. Instruction method 3)
In instruction method 3, the edge control device 10 transmits a plurality of instruction messages including a plurality of users to the DHCP server 40. In the example of instruction method 3 in Fig. 4, the edge control device 10 transmits two instruction messages corresponding to {user 1, user 2, ...} and {user 10, user 11, ...}. The time interval between the transmission of each message can be set arbitrarily (see instruction method 3 in Fig. 4). When the edge control device 10 is to issue an instruction as a compromise between instruction method 1 and instruction method 2, it transmits an instruction message using instruction method 3.

(2-2-5. Advantages of giving instructions by unit)
As described above, in the edge control system 100 according to the first embodiment, the edge control device 10 has a function for specifying a target user in a re-acquisition inducement instruction from the edge control device 10 to the DHCP server 40, and can send an instruction message at any user unit and time interval. The opposing DHCP server 40 can induce the specified user to re-acquire. Furthermore, the edge control device 10 can reduce the burst load on the edge router and L2 section due to DHCP address re-acquisition messages by limiting the target users (e.g., per device, per LAG, or per user) and adjusting the time interval of the message.

3. Edge control process flow
The flow of edge control processing according to the first embodiment will be described in detail using Figures 5 to 7. Figures 5 to 7 are sequence diagrams showing an example of the flow of edge control processing according to the first embodiment. Edge control processing 1 to 3 will be described below. Note that the processes described below can also be executed in a different order. Also, some of the processes described below may be omitted.

3-1. Flow of Edge Control Process 1
The flow of the edge control process 1 according to the first embodiment will be described in detail with reference to Fig. 5. Note that Fig. 5 uses an example of DHCPv6 as the communication method, but DHCPv4 or the like can also be used. In the example of Fig. 5, it is assumed that no linkage interface is introduced between the edge control device 10 and the DHCP server 40, or that even if a linkage interface is introduced, it is not compatible.

(3-1-1. Switching Execution Instruction Processing)
A maintenance technician M who performs the maintenance relocation transmits a switching execution instruction including switching information to the switching source edge router 20A that is performing user communication (step S201) with the user terminals 30 (30A, 30B, 30C, 30D) (step S202). Here, users 1 to 4 use user terminals 30A to 30D, respectively. User 1's user terminal 30A and user 2's user terminal 30B belong to VNE #a1, and user 30C of user 3 and user 4's user terminal 30D belong to VNE #b1. Note that "#a1" and "#b1" indicate aggregate addresses.

(3-1-2. DHCP blocking process)
The edge control device 10 sets a DHCPv6 blocking filter for the source edge router 20A to block DHCPv6 for users 1 and 2 (step S203), and issues an RA suppression command to delete the multicast setting (step S204). The edge control device 10 also inputs user configurations 21, such as user SO, for the destination edge router 20B (step S205). Similarly, the edge control device 10 sets a DHCPv6 blocking filter for the source edge router 20A to block DHCPv6 for users 3 and 4 (step S206), inputs an RA suppression command (step S207), and inputs user configurations 21, such as user SO, for the destination edge router 20B (step S208). As described above, even if the maintenance operator M issues a switching execution instruction only once, the edge control device 10 divides and executes the DHCP blocking process for each set unit (e.g., aggregated address).

(3-1-3. Pseudo DHCP Server Collaboration Processing)
The edge control device 10 transmits a DHCPv6 re-acquisition prompt instruction to the pseudo DHCP server 40V (step S209), and then receives the completion notification transmitted from the pseudo DHCP server 40V (step S210).

Here, the pseudo-DHCP server 40V only performs the process of receiving a DHCPv6 re-acquisition invitation instruction and sending a completion notification, so development costs are extremely low.

(3-1-4. IP switching process)
First, the maintenance person M transmits a DHCPv6 re-acquisition invitation instruction to the DHCP server 40 to switch the IPv6 addresses of users 1 to 4 (step S211). Next, the DHCP server 40 transmits a DHCPv6 re-acquisition invitation to the user terminals 30A to 30D (step S212). Subsequently, the user terminals 30A to 30D transmit DHCPv6 updates to the source edge router 20A and the destination edge router 20B to re-acquire addresses. At this time, the destination edge router 20B relays the DHCP packets, updates the DHCP binding table of the destination edge router 20B, and re-assigns the IP addresses, thereby completing the switching of the user communication path (step S213). The DHCP server 40 then transmits a DHCPv6 re-acquisition invitation completion notification to the maintenance person M (step S214).

In the above process, maintenance person M sends a DHCPv6 re-acquisition prompt to DHCP server 40, allowing for flexible response to the interface set on DHCP server 40. Furthermore, the information required when issuing an instruction is simple, consisting of only the target user's identifier, and can be handled manually. Furthermore, if maintenance person M issues an instruction to DHCP server 40 promptly, the time from issuing a switchover instruction to completing the switchover of the user communication path can be completed in a time similar to that of the technology using the linked interface described in non-patent document 1.

On the other hand, if the DHCP server 40 does not send a DHCPv6 re-acquisition prompt, the user terminals 30A-30D can use the timer-based DHCPv6 update as an opportunity to send a DHCPv6 update to the source edge router 20A and the destination edge router 20B to re-acquire an address. In other words, although it may take longer to complete the switchover, it is possible to avoid an increase in the workload of the maintenance person M. Furthermore, the switchover can be completed even if the maintenance person M misses out on performing certain tasks.

(3-1-5. Setting deletion process)
To delete the settings for users 1 to 4, the edge control device 10 deletes the user configuration 21, such as the user SO, held by the source edge router 20A (step S215). The edge control device 10 then starts the timer it has set and executes the processes from step S215 onward. Note that the timer is set longer than the T1 lease timer. The edge control device 10 also deletes the settings for the aggregation addresses ("#a1" and "#b1") held by the source edge router 20A (step S217) and sets the aggregation addresses ("#a1" and "#b1") for the destination edge router 20B (step S218). At this time, the maintenance worker M can check the progress of the setting deletion process with the edge control device 10, if necessary (step S216).

(3-1-6. Switching completion notification process)
When the setting deletion process is completed, the edge control device 10 transmits a switching completion notification to the maintenance person M who will be performing the maintenance relocation (step S219), and ends the process.

(3-1-7. Other)
5, if the cooperation interface between the edge control device 10 and the DHCP server 40 was incompatible at the time of the switching execution instruction process, but is later changed to be compatible, the pseudo-DHCP server cooperation process using the pseudo-DHCP server 40V becomes unnecessary. That is, in the process of step S209, the edge control device 10 transmits a DHCPv6 re-acquisition invitation instruction to the DHCP server 40, not to the pseudo-DHCP server 40V. Also, the process of step S211 becomes unnecessary. Also, in the process of step S214, the DHCP server 40 transmits a re-acquisition invitation completion notification to the edge control device 10, not to the maintenance person M.

3-2. Flow of Edge Control Process 2
The flow of the edge control process 2 according to the first embodiment will be described in detail with reference to Fig. 6. Note that Fig. 6 uses an example of DHCPv6 as the communication method, but DHCPv4 or the like can also be used. In the example of Fig. 6, it is assumed that a linkage interface that can support some users (users 1 and 2) is installed between the edge control device 10 and the DHCP server 40.

(3-2-1. Switching Execution Instruction Processing)
A maintenance technician M who performs the maintenance relocation transmits a switching execution instruction including switching information to the switching source edge router 20A that is performing user communication (step S301) with the user terminals 30 (30A, 30B, 30C, 30D) (step S302). Here, users 1 to 4 use user terminals 30A to 30D, respectively. User 1's user terminal 30A and user 2's user terminal 30B belong to VNE #a1, and user 30C of user 3 and user 4's user terminal 30D belong to VNE #b1. Note that "#a1" and "#b1" indicate aggregate addresses.

(3-2-2. DHCP blocking process)
The edge control device 10 executes DHCP blocking processing (steps S303 to S308) to block DHCPv6 for users 1 to 4. Note that the processing of steps S303 to S308 is the same as the processing of steps S203 to S208 in the edge control processing 1 described above, and therefore a description thereof will be omitted.

(3-2-3. IP switching process 1)
To switch the IPv6 addresses for users 1 and 2, the edge control device 10 transmits a DHCPv6 re-acquisition invitation instruction to the DHCP server 40, which has a compatible linkage interface installed (step S309). Next, the DHCP server 40 transmits a re-acquisition invitation to the user terminals 30A and 30B (step S310). Subsequently, the user terminals 30A and 30B transmit DHCPv6 updates to the source edge router 20A and the destination edge router 20B to re-acquire addresses. At this time, the destination edge router 20B relays the DHCP packets, updates the DHCP binding table of the destination edge router 20B, and re-assigns the IP addresses, thereby completing the switching of the user communication path (step S311). The DHCP server 40 then transmits a re-acquisition invitation completion notification to the edge control device 10 (step S312).

As shown in the above process, the edge control device 10 can select a user and change the collaboration method. The process of steps S309 to S312 enables IP switching to be completed in the same time as the edge control process shown in Non-Patent Document 1, in which a collaboration interface is introduced. For example, the edge control device 10 can change the collaboration method based on the user's characteristics, contracted service level, etc. Specifically, the edge control device 10 can shorten the switching completion time by associating high-grade users (e.g., corporate lines) with the DHCP server 40.

(3-2-4. Pseudo DHCP Server Collaboration Processing)
The edge control device 10 transmits a DHCPv6 re-acquisition prompt instruction to the pseudo DHCP server 40V (step S313), and then receives the completion notification transmitted from the pseudo DHCP server 40V (step S314).

(3-2-5. IP switching process 2)
First, maintenance person M transmits a DHCPv6 re-acquisition invitation instruction to DHCP server 40 to switch IPv6 addresses for users 3 and 4 (step S315). Next, DHCP server 40 transmits a DHCPv6 re-acquisition invitation to user terminals 30C and 30D (step S316). Subsequently, user terminals 30C and 30D transmit DHCPv6 updates to source edge router 20A and destination edge router 20B to re-acquire addresses. At this time, the destination edge router 20B relays the DHCP packets, updates the DHCP binding table of the destination edge router 20B, and re-assigns the IP addresses, thereby completing the switching of the user communication path (step S317). Then, DHCP server 40 transmits a re-acquisition invitation completion notification to maintenance person M (step S318).

As shown in the above process, the edge control device 10 can select a user and change the collaboration method. The processes in steps S315 to S318 enable IP switching to be completed in the same time as edge control process 1 in which a collaboration interface is not introduced.

(3-2-6. Setting deletion process)
The edge control device 10 executes a setting deletion process (steps S319 to S322) to delete the settings of users 1 to 4. Note that the process of steps S319 to S322 is the same as the process of steps S215 to S218 in the edge control process 1 described above, and therefore a description thereof will be omitted.

(3-2-7. Switching completion notification process)
When the setting deletion process is completed, the edge control device 10 transmits a switching completion notification to the maintenance person M who will be performing the maintenance relocation (step S323), and ends the process.

(3-2-8. Other)
In the example of FIG. 6, there are three edge control processes for switching time, which can be set as the service level for each user. The first process is a process in which, in cooperation with the DHCP server 40, an instruction is given to induce DHCPv6 re-acquisition. The second process is a process in which the maintenance person M gives an instruction to induce DHCPv6 re-acquisition after the pseudo DHCP server 40V responds. The third process is a process in which, after the pseudo DHCP server 40V responds, a voluntary DHCPv6 update is waited for. Also, in the example of FIG. 6, a case has been described in which only some users are the target of collaboration, but collaboration can also be performed on a unit such as a device or LAG.

3-3. Flow of Edge Control Process 3
The flow of the edge control process 3 according to the first embodiment will be described in detail with reference to Figure 7. Note that although Figure 7 uses an example of DHCPv6 as the communication method, DHCPv4 or the like can also be used. In the example of Figure 7, it is assumed that no linkage interface is introduced between the edge control device 10 and the DHCP server 40, or that even if a linkage interface is introduced, it is not compatible.

(3-3-1. Switching Execution Instruction Processing)
A maintenance technician M who performs the maintenance relocation transmits a switching execution instruction including switching information to the switching source edge router 20A that is performing user communication (step S401) with the user terminals 30 (30A, 30B, 30C, 30D) (step S402). Here, users 1 to 4 use user terminals 30A to 30D, respectively. User 1's user terminal 30A and user 2's user terminal 30B belong to VNE #a1, and user 30C of user 3 and user 4's user terminal 30D belong to VNE #b1. Note that "#a1" and "#b1" indicate aggregate addresses.

(3-3-2. DHCP blocking process)
The edge control device 10 executes DHCP blocking processing (steps S403 to S408) to block DHCPv6 for users 1 to 4. Note that the processing of steps S403 to S408 is the same as the processing of steps S203 to S208 in the edge control processing 1 described above, and therefore a description thereof will be omitted.

(3-3-3. IP switching process)
First, the edge control device 10 transmits a DHCPv6 re-acquisition invitation instruction to the pseudo DHCP server 40V to switch the IPv6 addresses of users 1 to 4 (step S409). At this time, the pseudo DHCP server 40V converts the received DHCPv6 re-acquisition invitation instruction into a format that matches the existing interface of the DHCP server 40 and transmits it to the DHCP server 40 (step S410). Next, the DHCP server 40 transmits a DHCPv6 re-acquisition invitation to the user terminals 30A to 30D (step S411). Subsequently, the user terminals 30A to 30D transmit DHCPv6 updates to the source edge router 20A and the destination edge router 20B to re-acquire addresses. At this time, the DHCP packet is relayed by the switching destination edge router 20B, the DHCP binding table of the switching destination edge router 20B is updated, and the IP address is again assigned, thereby completing the switching of the user communication path (step S412).The DHCP server 40 then transmits a DHCPv6 re-acquisition inducement completion notice to the pseudo DHCP server 40V (step S413).At this time, the pseudo DHCP server 40V converts the received DHCPv6 re-acquisition inducement completion notice into a format that matches the existing interface of the edge control device 10, and transmits the converted notice to the edge control device 10 (step S414).

As shown in the above process, the edge control device 10 can send a re-acquisition invitation instruction that has been converted to a compatible format via the pseudo DHCP server 40V to the DHCP server 40. In addition, the edge control device 10 can receive a re-acquisition invitation completion notification that has been converted to a compatible format via the pseudo DHCP server 40V from the DHCP server 40.

(3-3-4. Setting deletion process)
The edge control device 10 executes a setting deletion process (steps S415 to S418) to delete the settings of users 1 to 4. Note that the process of steps S415 to S418 is the same as the process of steps S215 to S218 in the edge control process 1 described above, and therefore a description thereof will be omitted.

(3-3-5. Switching completion notification process)
When the setting deletion process is completed, the edge control device 10 transmits a switching completion notification to the maintenance person M who will be performing the maintenance relocation (step S419), and ends the process.

(3-3-6. Other)
7, if the cooperation interface between the edge control device 10 and the DHCP server 40 was incompatible at the time of the switching execution instruction process, but is later changed to be compatible, the pseudo-DHCP server cooperation process using the pseudo-DHCP server 40V becomes unnecessary. That is, in the process of step S409, the edge control device 10 transmits a DHCPv6 re-acquisition invitation instruction to the DHCP server 40 without going through the pseudo-DHCP server 40V. Also, in the process of step S413, the DHCP server 40 transmits a DHCPv6 re-acquisition invitation completion notification to the edge control device 10 without going through the pseudo-DHCP server 40V.

4. Effects of the First Embodiment
Finally, the effects of the first embodiment will be described below: Effects 1 to 5 corresponding to the processing according to the first embodiment will be described below.

[4-1. Effect 1]
In the first embodiment described above, switching information related to switching of the edge router accommodating the user terminal 30 is acquired, and when the switching information is acquired, the source edge router 20A is configured to block DHCP packets and cancel multicast communication, and when the blocking of DHCP packets and the cancellation of multicast communication are configured, user setting information is input to the destination edge router 20B, and based on the switching information, the pseudo DHCP server 40V, which is a virtual server, is instructed to induce the user terminal 30 to re-acquire an IP address, a notification is received from the pseudo DHCP server 40V that the instruction to induce re-acquisition of an IP address has been received, and when a predetermined time has elapsed since the notification that the instruction to induce re-acquisition of an IP address was received, the user setting information held by the source edge router 20A is deleted. Therefore, in the first embodiment, maintenance relocation of the edge router 20 can be carried out effectively.

[4-2. Effect 2]
In the first embodiment described above, when the edge router 20A is connected to the DHCP server 40, which is a physical server, via a predetermined interface in a compatible manner, the edge router 20A instructs the DHCP server 40 to induce re-acquisition of an IP address, receives a notification from the DHCP server 40 that the inducement for re-acquisition has been completed, and deletes the user setting information held by the edge router 20A upon receiving the notification that the inducement for re-acquisition has been completed. Therefore, in the first embodiment, when a linking interface is introduced, switching can be performed in a short time, and maintenance relocation of the edge router 20 can be performed effectively.

[4-3. Effect 3]
In the first embodiment described above, an instruction to induce re-acquisition of an IP address is given for each predetermined unit at a predetermined time interval, and the instruction to induce re-acquisition is given to the DHCP server 40 for units that the DHCP server 40 can handle, and the instruction to induce re-acquisition is given to the dummy DHCP server 40V for units that the DHCP server 40 cannot handle. Therefore, in the first embodiment, it is possible to select cooperation with an interface for each predetermined unit, and maintenance relocation of the edge router 20 can be performed effectively.

[4-4. Effect 4]
In the first embodiment described above, an instruction to induce re-acquisition of an IP address converted into a compatible format by the pseudo DHCP server 40V is transmitted to the DHCP server 40, a notification is received from the DHCP server 40 that the inducement for re-acquisition of the IP address converted into a compatible format by the pseudo DHCP server 40V has been completed, and when the notification that the inducement for re-acquisition has been completed is received, the user setting information held by the switching source edge router 20A is deleted. Therefore, in the first embodiment, even if a cooperation interface is not introduced, maintenance relocation of the edge router 20 can be effectively performed using an existing interface.

[4-5. Effect 5]
In the first embodiment described above, the trigger to reacquire an IP address is instructed for each device, LAG, or user. Therefore, in the first embodiment, the communication load can be reduced by limiting the communication target and communication time, and maintenance relocation of the edge router 20 can be effectively performed.

[System configuration, etc.]
The components of each device shown in the drawings according to the above embodiments are conceptual functional units and do not necessarily have to be physically configured as shown. In other words, the specific form of distribution and integration of each device is not limited to that shown in the drawings, and all or part of the devices can be functionally or physically distributed and integrated in any unit depending on various loads, usage conditions, etc. Furthermore, all or any part of the processing functions performed by each device can be realized by a CPU and a program analyzed and executed by the CPU, or can be realized as hardware using wired logic.

Furthermore, among the processes described in the above embodiments, all or part of the processes described as being performed automatically can be performed manually, or all or part of the processes described as being performed manually can be performed automatically using known methods. In addition, the information, including the processing procedures, control procedures, specific names, various data, and parameters shown in the above documents and drawings, can be changed as desired unless otherwise specified.

〔program〕
It is also possible to create a program written in a computer-executable language that executes the processes executed by the edge control device 10 described in the above embodiment. In this case, the same effects as those of the above embodiment can be achieved by having a computer execute the program. Furthermore, such a program may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read and executed by a computer to achieve the same processes as those of the above embodiment.

Figure 8 is a diagram showing a computer that executes a program. As illustrated in Figure 8, the computer 1000 has, for example, memory 1010, a CPU 1020, a hard disk drive interface 1030, a disk drive interface 1040, a serial port interface 1050, a video adapter 1060, and a network interface 1070, and each of these components is connected by a bus 1080.

As illustrated in FIG. 8, the memory 1010 includes a ROM (Read Only Memory) 1011 and a RAM 1012. The ROM 1011 stores a boot program such as a BIOS (Basic Input Output System). The hard disk drive interface 1030 is connected to a hard disk drive 1090 as illustrated in FIG. 8. The disk drive interface 1040 is connected to a disk drive 1100 as illustrated in FIG. 8. A removable storage medium such as a magnetic disk or optical disk is inserted into the disk drive 1100. The serial port interface 1050 is connected to a mouse 1110 and a keyboard 1120 as illustrated in FIG. 8. The video adapter 1060 is connected to a display 1130 as illustrated in FIG. 8.

Here, as illustrated in FIG. 8, the hard disk drive 1090 stores, for example, an OS 1091, an application program 1092, a program module 1093, and program data 1094. In other words, the above programs are stored, for example, on the hard disk drive 1090 as program modules that describe instructions to be executed by the computer 1000.

In addition, the various data described in the above embodiments are stored as program data, for example, in memory 1010 or hard disk drive 1090. Then, the CPU 1020 reads the program module 1093 and program data 1094 stored in memory 1010 or hard disk drive 1090 into RAM 1012 as needed, and executes various processing procedures.

The program module 1093 and program data 1094 related to the program do not necessarily have to be stored on the hard disk drive 1090, but may be stored, for example, on a removable storage medium and read by the CPU 1020 via a disk drive or the like. Alternatively, the program module 1093 and program data 1094 related to the program may be stored in another computer connected via a network (such as a LAN (Local Area Network), WAN (Wide Area Network)), and read by the CPU 1020 via the network interface 1070.

The above embodiments and their variations are included in the technology disclosed in this application, as well as in the scope of the invention described in the claims and their equivalents.

10 Edge control device (communication control device)
11 Input unit 12 Output unit 13 Communication unit 14 Storage unit 15 Control unit 151 Edge control unit 151a Acquisition unit 151b Setting unit 151c Input unit 151d Instruction unit 151e Reception unit 151f Deletion unit 152 Pseudo server control unit 152a Construction unit 20, 20A, 20B Edge router 21 User setting information (user configuration)
30, 30A, 30B, 30C, 30D User terminal 40 DHCP server 40V Pseudo DHCP server 50, 50A, 50B User DB
60, 60A, 60B Communication network 100 Edge control system

Claims (7)

an acquisition unit that acquires switching information regarding switching of an edge router that accommodates a user terminal;
a setting unit that, when the acquisition unit acquires the switching information, sets the switching source edge router to block DHCP (Dynamic Host Configuration Protocol) packets and cancel multicast communication;
an input unit that inputs the user's setting information to a switching destination edge router when the setting unit sets blocking of the DHCP packets and cancellation of the multicast communication;
an instruction unit that instructs a pseudo DHCP server, which is a virtual server, to induce the terminal to reacquire an IP (Internet Protocol) address based on the switching information;
a reception unit that receives a notification from the pseudo DHCP server that the instruction to induce re-acquisition has been received;
a deletion unit that deletes the user's configuration information held by the switching source edge router when a predetermined time has elapsed since the notification of receipt of the instruction to induce re-acquisition has been received;
A communication control device comprising: The instruction unit
If the device is connected to a DHCP server, which is a physical server, via a predetermined interface, the device instructs the DHCP server to trigger the re-acquisition of the DHCP server.
The reception unit
receiving a notification from the DHCP server that the re-acquisition has been initiated;
The deletion unit
When receiving a notification that the trigger for re-acquisition has been completed, the switching source edge router deletes the user's setting information held by the switching source edge router.
2. The communication control device according to claim 1. The instruction unit
Instructing the trigger for reacquisition at predetermined time intervals for each predetermined unit;
Instructing the DHCP server to induce the reacquisition for the unit that the DHCP server can handle;
For the unit that the DHCP server cannot handle, the pseudo DHCP server is instructed to induce reacquisition.
3. The communication control device according to claim 2. The instruction unit
Sending to a DHCP server the instruction to induce re-acquisition, which has been converted into a format that can be handled by the pseudo DHCP server;
The reception unit
receiving a notification from the DHCP server that the re-acquisition inducement has been completed and converted into a format that can be handled by the pseudo DHCP server;
The deletion unit
When receiving a notification that the trigger for re-acquisition has been completed, the switching source edge router deletes the user's setting information held by the switching source edge router.
2. The communication control device according to claim 1. The instruction unit
The triggering of the reacquisition is instructed for each device, LAG (Link Aggregation Group), or user.
5. The communication control device according to claim 1, wherein the communication control device is a communication control device. A communication control method executed by a communication control device,
an acquisition step of acquiring switching information regarding switching of an edge router accommodating a user terminal;
a setting step of setting the switching source edge router to block DHCP packets and cancel multicast communication when the switching information is acquired in the acquisition step;
an input step of inputting the user's setting information to a switching destination edge router when the setting step sets blocking of the DHCP packet and cancellation of the multicast communication;
an instruction step of instructing a pseudo DHCP server, which is a virtual server, to induce the terminal to reacquire an IP address based on the switching information;
a receiving step of receiving a predetermined notification based on the instruction to induce re-acquisition from the pseudo DHCP server;
a deletion step of deleting the user's setting information held by the switching source edge router when a predetermined time has elapsed since the notification of receipt of the instruction to induce re-acquisition has been received;
A communication control method comprising: an acquisition procedure for acquiring switching information regarding switching of an edge router accommodating a user terminal;
a setting procedure for setting the switching source edge router to block DHCP packets and cancel multicast communication when the switching information is acquired in the acquisition procedure;
an input procedure for inputting the user's setting information to a switching destination edge router when the setting procedure sets blocking of the DHCP packet and cancellation of the multicast communication;
an instruction procedure for instructing a pseudo DHCP server, which is a virtual server, to induce the terminal to reacquire an IP address based on the switching information;
a receiving procedure for receiving a predetermined notification based on the instruction to induce re-acquisition from the pseudo DHCP server;
a deletion procedure for deleting the user's configuration information held by the switching source edge router when a predetermined time has elapsed since the notification of receipt of the instruction to induce re-acquisition has been received;
A communication control program that causes a computer to execute the above.