JP7419927B2 - Control device, control method and control program - Google Patents

Description

The present invention relates to a control device, a control method, and a control program. In particular, the present invention relates to a control device, a control method, and a control program for controlling a relay device.

In order to realize a Layer 2 location-free virtual network with multiple relay devices, overlay technologies such as MPLS (see Patent Document 1), VXLAN (see Patent Document 2), and flow control technologies such as OpenFlow (Patent Document 1) are required. 3) is required.

Japanese Patent Application Publication No. 2013-009049 Japanese Patent Application Publication No. 2016-152567 Japanese Patent Application Publication No. 2016-192757

The following analysis was made from the perspective of the present invention. In addition, each disclosure of the above-mentioned prior art documents is incorporated into this book by reference.

The techniques disclosed in Patent Documents 1 to 3 have a problem in that when the number of relay devices increases, the network configuration becomes complicated and control by a control device becomes difficult.

Therefore, an object of the present invention is to provide a technique that contributes to facilitating control by a control device.

According to a first aspect of the present invention, topology information indicating the connection relationship between each relay device, a virtual router, and a virtual switch in a network constituted by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device. a storage unit that stores virtual network information indicating the configuration of the included virtual network, and relay device group information indicating a group of relay devices configuring the same virtual network;
a route search unit that searches for a route between a core node selected from layer 3 relay devices and each layer 2 relay device based on the topology information and the relay device group information;
Based on the relay device group information and the route searched by the route search unit, the shortest layer 3 relay device from each layer 2 relay device is determined, and multiple layer 2 relay devices constituting the same virtual switch If the shortest layer 3 relay devices are all the same, the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch, and multiple layer 2 relay devices that configure the same virtual switch A control device is provided that includes a determining unit that determines the core node to be the layer 3 relay device that sets the VLAN interface of the virtual switch when the shortest layer 3 relay device is different for the virtual switch.

According to a second aspect of the present invention, topology information indicating the connection relationship between each relay device, a virtual router, and a virtual switch in a network configured by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device. Based on the topology information and the relay device group information stored in a storage unit that stores virtual network information indicating a configuration of a virtual network including virtual networks, and relay device group information indicating a group of relay devices constituting the same virtual network. searching for a route between the core node selected from the layer 3 relay devices and each layer 2 relay device;
Based on the relay device group information and the route searched by the route search unit, the shortest layer 3 relay device from each layer 2 relay device is determined, and multiple layer 2 relay devices constituting the same virtual switch If the shortest layer 3 relay devices are all the same, the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch, and multiple layer 2 relay devices that configure the same virtual switch A control method is provided that includes the step of determining a core node as a layer 3 relay device for setting a VLAN interface of a virtual switch when the shortest layer 3 relay device is different for the virtual switch.

According to a third aspect of the present invention, topology information indicating the connection relationship between each relay device in a network configured by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device, and a virtual network including a virtual switch. Based on the topology information and the relay device group information stored in a storage unit that stores virtual network information indicating the configuration of the same virtual network and relay device group information indicating the group of relay devices that constitute the same virtual network, a route search process that searches for a route between the core node selected from the three relay devices and each layer 2 relay device;
Based on the relay device group information and the route searched by the route search unit, the shortest layer 3 relay device from each layer 2 relay device is determined, and multiple layer 2 relay devices constituting the same virtual switch If the shortest layer 3 relay devices are all the same, the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch, and multiple layer 2 relay devices that configure the same virtual switch A control program is provided that causes a computer to execute a determination process of determining a core node as a layer 3 relay device for setting a VLAN interface of a virtual switch when the shortest layer 3 relay device is different.

According to each aspect of the present invention, a technique that contributes to facilitating control by a control device is provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining an overview of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining an overview of the present invention. FIG. 1 is a diagram showing an example of a network configuration according to the first embodiment. 1 is a block diagram showing one configuration of a control device 11. FIG. FIG. 3 is a diagram illustrating an example of relay device group information. FIG. 3 is a diagram showing an example of a virtual network table. FIG. 3 is a diagram showing an example of a virtual switch table. It is a figure which shows an example of a mapping table. FIG. 3 is a diagram showing an example of a virtual router table. FIG. 3 is a diagram showing an example of a virtual router interface table. FIG. 3 is a diagram showing an example of a virtual router IP address table. FIG. 2 is a sequence diagram showing the flow of processing when constructing a virtual network. It is a figure showing an example of route information. FIG. 3 is a flowchart showing the flow of command generation processing. FIG. 3 is a flowchart showing the flow of layer 3 relay device determination processing. FIG. 3 is a diagram for explaining layer 3 relay device determination processing. FIG. 3 is a diagram for explaining layer 3 relay device determination processing. FIG. 3 is a diagram for explaining layer 3 relay device determination processing. FIG. 3 is a flowchart showing the flow of interface determination processing. FIG. 3 is a diagram for explaining interface determination processing. FIG. 3 is a diagram for explaining interface determination processing. It is a flowchart figure which shows the flow of IP address determination processing for internal communication. FIG. 3 is a diagram for explaining internal communication IP address determination processing. FIG. 3 is a diagram for explaining internal communication IP address determination processing. FIG. 1 is a diagram showing an example of a virtual network constructed according to the present invention.

Preferred embodiments of the present invention will be described in detail with reference to the drawings. Note that the drawing reference numerals added to the following description are added to each element for convenience as an example to aid understanding, and are not intended to limit the present invention to the illustrated embodiment. Furthermore, connection lines between blocks in each figure include both bidirectional and unidirectional connections. The unidirectional arrows schematically indicate the main signal (data) flow, and do not exclude bidirectionality. Furthermore, in the circuit diagrams, block diagrams, internal configuration diagrams, connection diagrams, etc. shown in the present disclosure, although not explicitly stated, an input port and an output port are present at the input end and output end of each connection line, respectively. The same applies to the input/output interface.

Note that the following abbreviations are used in this application.
MPLS: Multi-Protocol Label Switching
LAN: Local Area Network
VLAN: Virtual LAN
VXLAN: Virtual eXtensible LAN
VRF: Virtual Routing and Forwarding
PC: Personal Computer
CLI: Command Line Interface
REST: REpresentational State Transfer
API: Application Programming Interface
SNMP: Simple Network Management Protocol
ID:IDentifier

First, an overview of one embodiment of the present invention will be described. As shown in FIG. 1, the control device 11 includes a storage section, a route search section, and a determination section. The storage unit stores topology information, virtual network information, and relay device group information. Topology information is information indicating the connection relationship between each relay device in a network configured by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device. Virtual network information is information indicating the configuration of a virtual network including a virtual switch. Relay device group information is information indicating a group of relay devices that constitute the same virtual network.

The route search unit searches for a route between a core node selected from among the layer 3 relay devices and each layer 2 relay device based on the topology information and the relay device group information.

The determining unit first determines the shortest layer 3 relay device from each layer 2 relay device based on the relay device group information and the route searched by the route search unit. Then, if the shortest layer 3 relay devices are all the same among the plurality of layer 2 relay devices constituting the same virtual switch, the determination unit selects the shortest layer 3 relay device as the layer 3 relay device for setting the VLAN interface of the virtual switch. Decided to be a relay device. On the other hand, if the shortest layer 3 relay devices among the plurality of layer 2 relay devices configuring the same virtual switch are different, the core node is determined as the layer 3 relay device that sets the VLAN interface of the virtual switch.

The above configuration makes it possible to abstract a plurality of layer 3 relay devices into one virtual router and a layer 2 network composed of a plurality of layer 3 relay devices and layer 2 relay devices into one virtual switch. For example, a virtual network as shown in FIG. 2(2) is constructed from a network made up of a VRF and a VLAN as shown in FIG. 2(1). Since this virtual network has one virtual router, the configuration of the virtual network is simple and control by the control device 11 is facilitated.

[Embodiment 1]
Embodiment 1 will be described below as a specific example of the present invention. Embodiment 1 will be described using the network configuration shown in FIG. 3 as an example. Specifically, the system of the first embodiment includes a control device 11, layer 2 relay devices 21-25, layer 3 relay devices 31-33, and terminals 41-49.

The control device 11 will be explained in detail later.

The layer 2 relay devices 21 to 25 are devices that relay layer 2 communications, and have functions of multiplexing layer 2 communications using VLAN and permitting VLAN transfer of interfaces. Layer 2 relay device 21 is connected to terminal 41 via interface 21-1, connected to control device 11 via interface 21-2, and connected to layer 3 relay device 31 via interface 21-3. . Layer 2 relay device 22 is connected to terminal 42 through interface 22-1, connected to terminal 43 through interface 22-2, and connected to layer 3 relay device 32 through interface 22-3. Layer 2 relay device 23 is connected to terminal 44 through interface 23-1, connected to terminal 45 through interface 23-2, and connected to layer 3 relay device 32 through interface 22-3. Layer 2 relay device 24 is connected to terminal 46 through interface 24-1, connected to terminal 47 through interface 24-2, and connected to layer 3 relay device 33 through interface 24-3. Layer 2 relay device 25 is connected to terminal 48 through interface 25-1, connected to terminal 49 through interface 25-2, and connected to layer 3 relay device 33 through interface 25-3.

The layer 3 relay devices 31 to 33 are devices that relay layer 3 communications, and have a function of multiplexing layer 3 communications using a VRF and permitting a VLAN to perform layer 3 communication using the VRF. Note that the layer 3 relay devices 31 to 33 can also perform layer 2 relay equivalent to the layer 2 relay devices 21 to 25. Layer 3 relay device 31 is connected to layer 3 relay device 32 through interface 31-1, connected to layer 3 relay device 33 through interface 31-2, and connected to layer 2 relay device through interface 31-3. Connected to 21. The layer 3 relay device 32 is connected to the layer 2 relay device 22 through an interface 32-1, connected to the layer 2 relay device 23 through an interface 32-2, and connected to the layer 3 relay device through an interface 32-3. 31. Layer 3 relay device 33 is connected to layer 2 relay device 24 through interface 33-1, connected to layer 2 relay device 25 through interface 33-2, and connected to layer 3 relay device through interface 33-3. 31. Note that in this application, when the layer 2 relay devices 21 to 25 and the layer 3 relay devices 31 to 33 are collectively referred to, they may be simply referred to as "relay device."

The terminals 41 to 49 are PCs used by users.

Note that each device and terminal are connected by a data transfer link. Here, the layer 2 relay devices 21 to 25 and the layer 3 relay devices 31 to 33 receive control commands from the control device 11 via the data transfer link, but directly control the control device 11 and each relay device. You can also connect using a link. Further, the layer 2 relay devices 21 to 25 and the layer 3 relay devices 31 to 33 can also form a stack of a plurality of relay devices for equipment redundancy. Further, the network configuration, particularly the number of relay devices, is not limited to that shown in FIG. 1.

FIG. 4 is a block diagram showing the configuration of the control device 11. As shown in FIG. As shown in FIG. 4, the control device 11 includes a relay device communication section 11-1, a topology acquisition section 11-2, a topology table 11-3, an information input section 11-4, and a relay device group information storage section 11-5. have The control device 11 further includes a route search section 11-6, a virtual network information storage section 11-7, and a relay device control command generation section 11-8.

The relay device communication unit 11-1 performs control communication with each relay device. Specifically, the relay device communication unit 11-1 establishes control sessions with layer 2 relay devices 21 to 25 and layer 3 relay devices 31 to 33, and transmits and receives control commands. As a control command, CLI via telnet/ssh may be used. Additionally, RESTful API and SNMP may be used.

The topology acquisition unit 11-2 acquires topology information between relay devices. The topology information includes, for example, adjacent relay device recognition information collected from each relay device. Specifically, the topology information of the layer 2 relay devices 21 to 25 and the layer 3 relay devices 31 to 33 is acquired via the relay device communication unit 11-1. The topology information can be acquired by the topology acquisition unit 11-2 by a method of absorbing adjacent relay device recognition information of a relay device. Link Layer Discovery Protocol is a typical recognition protocol between switches.

The topology table 11-3 stores topology information. The topology information stored in the topology table 11-3 includes not only the adjacent relay device recognition information acquired by the topology acquisition unit 11-2 but also the adjacent relay device recognition information directly input through the information input unit 11-4. Also included.

The information input unit 11-4 is an interface for a system administrator to input information. For example, topology information, relay device group information, virtual network information, etc. are input via the information input unit 11-4 using a CLI (character user interface), GUI (graphical user interface), or the like.

The relay device group information storage unit 11-5 stores relay device group information input via the information input unit 11-4. A relay device group means a group of relay devices that constitute the same virtual network. For example, as shown in FIG. 5, the relay device group information associates a relay device group ID, an ID of a relay device belonging to the relay device group, and core node information indicating that it is a core node in the relay device group. This is a relay device group table. Note that the core node is a relay device that physically bundles all the relay devices, and one core node is selected for each relay device group. For example, a core node is a core switch connected to a gateway.

The route search unit 11-6 searches for a route based on the virtual network information and topology information. Specifically, the route search unit 11-6 calculates the route between the core node and the relay device connected to the terminal, and calculates the route between the core node and at least all other relay devices connected to the terminal. Search for a spanning tree route that allows communication. Here, multiple spanning tree routes may be searched for each VLAN. A minimum spanning tree (typically Primm's method and Kruskal's method) is used as a route calculation method. When searching for a route, relay devices to which no terminals are connected may be excluded.

The virtual network information storage unit 11-7 stores virtual network information input by the system administrator via the information input unit 11-4. Specifically, the virtual network information storage unit 11-7 stores a virtual network table, a virtual switch table, a mapping table, a virtual router table, a virtual router interface table, and a virtual router IP address table.

The virtual network table is a table that defines a virtual network that is an object for slicing a network, and for example, as shown in FIG. 6, a virtual network ID and a relay device group ID are associated with each other.

The virtual switch table is a table that defines virtual switches, which are objects of the virtual layer 2 network. For example, as shown in FIG. 7, the virtual network ID to which the virtual switch belongs, the virtual switch ID, and the VLAN ID correspond to each other. Can be attached. Note that the VLAN ID can be input by the system administrator via the information input section 11-4, or the control device 11 can automatically allocate an unused VLAN ID.

The mapping table is a table that defines an interface of a relay device to which a terminal belonging to the layer 2 network of the virtual switch is connected. In the mapping table, for example, as shown in FIG. 8, a virtual switch ID, a relay device ID, a relay device interface, and VLAN tag information are associated with each other. VLAN Tag information is information that indicates whether communication between a virtual switch and a terminal is multiplexed using VLAN Tags, and is described as Tagged when communicating with a VLAN Tag, and Untagged when communicating without a VLAN Tag. Ru.

The virtual router table is a table that defines virtual routers that are objects of virtual layer 3 nodes. In the virtual router table, for example, as shown in FIG. 9, a virtual network ID, a virtual router ID, a VRF name, an internal communication VLAN, and an internal communication subnet are associated with each other. The VRF name can be input by the system administrator via the information input section 11-4, or can be automatically generated by the control device 11. The internal communication VLAN is a VLAN for internal communication between VRFs of virtual routers, and can be input by the system administrator via the information input section 11-4, or can be input by the control device 11 within a predetermined range. It is also possible to allocate automatically from The internal communication subnet is a subnet for internal communication between VRFs of virtual routers, and can be input by the system administrator via the information input section 11-4, or can be input by the control device 11 within a predetermined range. It is also possible to allocate automatically from

The virtual router interface table is a table that defines the interface of a virtual router, and for example, as shown in FIG. 10, a virtual router ID, a virtual router interface ID, and a virtual switch ID are associated with each other.

The virtual router IP address table is a table that defines IP addresses of virtual router interfaces. In the virtual router IP address table, for example, as shown in FIG. 11, a virtual router interface ID for setting an IP address is associated with a gateway IP address serving as a layer 3 gateway of the virtual router interface. It is also possible to set multiple gateway IP addresses to one virtual router interface.

The relay device control command generation unit 11-8 generates a control command for controlling each relay device based on the route searched by the route search unit 11-6 and the virtual network information. Note that the relay device control command generation unit 11-8 may also be referred to as a “determination unit”.

Below, the flow of processing in the control device 11 will be explained. When the relay device group information is input by the system administrator (step 1-1), the information input unit 11-4 stores the relay device group information in the relay device group information storage unit 11-5 (step 1-2). ). Similarly, when topology information is input by the system administrator or topology information is acquired by the topology acquisition unit 11-2, the information input unit 11-4 stores the topology information in the topology table 11-3. The above processing corresponds to pre-processing before constructing a virtual network.

The following is the process when building a virtual network. As shown in FIG. 12, when virtual network information is input by the system administrator (step 1-3), the information input unit 11-4 stores the virtual network information in the virtual network information storage unit 11-7 ( Steps 1-4). Here, the input of virtual network information by the system administrator includes an instruction to construct a virtual network, but the input of virtual network information and the instruction to construct a virtual network may be performed separately.

Next, the virtual network information storage unit 11-7 notifies the relay device control command generation unit 11-8 of the update of the virtual network information (step 1-5). The relay device control command generation unit 11-8 requests the route search unit 11-6 to search for a route (step 1-6). The route search unit 11-6 acquires topology information from the topology table 11-3 (step 1-7) and acquires relay device group information from the relay device group information storage unit 11-5 (step 1-8). . Then, the route search unit 11-6 searches for a route between the relay device and the core node for each relay device group based on the topology information and the relay device group information (step 1-9), and the relay device control command generation unit 11 -8 as route information (step 1-10). Note that, as shown in FIG. 13, the route information is information that associates the ID of a relay device with detailed route information that is a list of interfaces between core nodes of a relay device group to which the relay device belongs.

Next, the relay device control command generation unit 11-8 generates a command to be sent to the relay device based on the virtual network information and route information (step 1-11). Then, the relay device control command generation unit 11-8 requests the relay device communication unit 11-1 to send a command (step 1-12), and the relay device communication unit 11-1 communicates with the layer 2 relay devices 21 to 25 and A command is sent to the layer 3 relay devices 31 to 33 (step 1-13). Note that steps 1-9 and 1-10 are repeated as many times as the number of commands.

The command generation process in step 1-11 will be described in detail below. As shown in FIG. 14, the relay device control command generation unit 11-8 determines a layer 3 relay device for setting the VRF of the virtual router and the VLAN interface of the virtual switch (step 2-1). Then, the relay device control command generation unit 11-8 determines the interface of the relay device for setting the VLAN of the virtual switch (step 2-2), and determines the interface for setting the VLAN for internal communication of the virtual router and the IP for internal communication. Determine the address (step 2-3).

The layer 3 relay device determination process in step 2-1 will be described in detail below. As shown in FIG. 15, the relay device control command generation unit 11-8 refers to the route information and determines the shortest layer 3 relay device for each virtual switch and relay device listed in the mapping table (FIG. 8). (Step 3-1). For example, in the example of the route information shown in FIG. 13 and the mapping table shown in FIG. 8, the shortest layer 3 relay device is determined as shown in FIG. 16.

Next, the relay device control command generation unit 11-8 checks whether all the shortest layer 3 relay devices are the same for each virtual switch (step 3-2). If they are all the same (step 3-2, YES), the same shortest layer 3 relay device is set as the layer 3 relay device for setting the VLAN interface of the virtual switch (step 3-3). On the other hand, if they are different (step 3-2, NO), the core node is set as a layer 3 relay device that sets the VLAN interface of the virtual switch (step 3-4). For example, in the example shown in FIG. 16, the layer 3 relay device 32 is determined for the virtual switch c1, and the layer 3 relay device 31, which is a core node, is determined for the virtual switch c2. When the information is integrated with the information stored in the virtual router interface table of FIG. 10, it becomes what is shown in FIG. 17. In other words, as shown in FIG. 17, a layer 3 relay device that configures the VLAN interface of one or more virtual switches is assigned to one virtual router.

Then, the relay device control command generation unit 11-8 sets the layer 3 relay device that configures the VLAN interface of the virtual switch for each virtual router as the layer 3 relay device that configures the VRF (step 3-5). When the information is integrated with the information stored in the virtual switch table (FIG. 7), virtual router table (FIG. 9), and virtual router IP address table (FIG. 11), it becomes what is shown in FIG.

The interface determination process in step 2-2 will be described in detail below. As shown in FIG. 19, the relay device control command generation unit 11-8 refers to the route information (FIG. 13) and identifies the relay device and the shortest layer 3 for each virtual switch and relay device in the mapping table (FIG. 8). Detailed route information between relay devices is extracted (step 4-1). Then, the relay device control command generation unit 11-8 checks the number of shortest layer 3 relay devices in the detailed route information extracted for each virtual switch (step 4-2). If there is a plurality of shortest layer 3 relay devices (step 4-2, YES), the relay device control command generation unit 11-8 extracts detailed route information between the shortest layer 3 relay device and the core node from the route information. (Step 4-3). On the other hand, if there is one shortest layer 3 relay device (step 4-2, NO), the relay device control command generation unit 11-8 does not extract detailed route information. The above processing is summarized as shown in FIG. 20. Note that the above process extracts the interface between the layer 2 relay device and the shortest layer 3 relay device for each virtual switch from the route searched by the route search unit, and identifies it as the interface of the tagged VLAN in the mapping table. This can also be said to be a process of determining the extracted interface as the tagged VLAN interface in addition to the extracted interface.

Subsequently, the relay device control command generation unit 11-8 determines the interface of the relay device in the detailed route information extracted in steps 4-1 and 4-3 for each virtual switch as the interface for setting the tagged VLAN. Furthermore, the relay device control command generation unit 11-8 determines the interface whose VLAN Tag information in the mapping table is Tagged as the interface for setting the Tagged VLAN. Then, the relay device control command generation unit 11-8 determines the interface whose VLAN tag information is Untagged as the interface for setting the Untagged VLAN (step 4-4). The above processing can be summarized as shown in FIG. 21.

The internal communication IP address determination process in step 2-3 will be described in detail below. As shown in FIG. 22, the relay device control command generation unit 11-8 checks the number of layer 3 relay devices for which VRF is to be set for each virtual router (step 5-1). Here, if the number of layer 3 relay devices for which VRF is to be set is one (step 5-1, NO), no setting is necessary and the process ends. On the other hand, if there are multiple layer 3 relay devices for which VRF is to be configured (step 5-1, YES), detailed route information between the layer 3 relay devices for which VRF is to be configured and the core node is extracted from the route information. , determines the interface for setting the internal communication VLAN (step 5-2). Note that the detailed route information to be extracted is shown in FIG.

Subsequently, the relay device control command generation unit 11-8 sets the internal communication VLAN of the virtual router table (FIG. 9) in the extracted route detailed information (step 5-2). Then, the relay device control command generation unit 11-8 allocates an internal communication IP address from the internal communication subnet of the virtual router table (FIG. 9) to the layer 3 relay device for which VRF is set for each virtual router (step 5- 3). The internal communication IP address is set in the VLAN interface created by creating a VLAN interface for the internal communication VLAN in the layer 3 relay device that sets the VRF. A routing protocol such as OSPF is also set in the VRF and VLAN interface to advertise IP routing information between the VRFs. Figure 24 shows the VRF name set in the layer 3 relay device for each virtual router, the layer 3 relay device setting the VRF, the VLAN interface of the internal communication VLAN set in the VRF, and the internal communication VLAN interface set in the VLAN interface. This is an example of an IP address. Note that the above process can also be rephrased as a process of determining a new internal communication IP address for each of the layer 3 relay devices that make up the virtual router.

As described above, according to the present invention, it is possible to abstract a layer 2 network composed of a plurality of layer 3 relay devices and layer 2 relay devices into one virtual switch. Specifically, from the network shown in FIG. 3, as shown in FIG. 25, a virtual network b1 to which a virtual router d1 and virtual switches c1 to c3 are connected, and a virtual router d2 and virtual switches c4 and c5 are connected. A connected virtual network b2 is constructed. Here, there is only one virtual router in each of the virtual networks b1 and b2, and the configuration of the virtual network is simple, which facilitates control by the control device.

Further, in the first embodiment, the control device 11 determines whether the virtual switch mapping straddles a plurality of layer 3 relay devices or not, and performs VLAN settings and VRF settings. Therefore, in a layer 2 network that does not require layer 2 location freedom, the range of the broadcast domain can be kept under one layer 3 relay device. In addition, only a layer 2 network that requires layer 2 location freeness can realize a layer 2 network that spans a plurality of layer 3 relay devices. In other words, the number of locations where technologies such as MPLS, which are necessary for realizing a layer 2 location-free virtual network, is applied is reduced.

Part or all of the above embodiments may be described as in the following additional notes, but are not limited to the following.

(Additional note 1)
Topology information indicating the connection relationship between each relay device in a network configured by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device, virtual network information indicating the configuration of a virtual network including a virtual router and a virtual switch, and a storage unit that stores relay device group information indicating a group of relay devices constituting the same virtual network;
a route search unit that searches for a route between a core node selected from layer 3 relay devices and each layer 2 relay device based on the topology information and the relay device group information;
Based on the relay device group information and the route searched by the route search unit, the shortest layer 3 relay device from each layer 2 relay device is determined, and multiple layer 2 relay devices constituting the same virtual switch If the shortest layer 3 relay devices are all the same, the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch, and multiple layer 2 relay devices that configure the same virtual switch a determining unit that determines the core node as a layer 3 relay device for setting a VLAN interface of the virtual switch when the shortest layer 3 relay device is different for each;
A control device having:

(Additional note 2)
The control device according to supplementary note 1, wherein the determining unit allocates, to one virtual router, a layer 3 relay device that configures a VLAN interface of one or more of the virtual switches.

(Additional note 3)
The storage unit further stores a mapping table that associates the interface ID of the layer 2 relay device with VLAN Tag information indicating whether the interface is a tag VLAN interface,
The determining unit extracts an interface between a layer 2 relay device and the shortest layer 3 relay device for each virtual switch from the route searched by the route searching unit, and determines in the mapping table that the interface is an interface of a tagged VLAN. determining the extracted interface in addition to the identified interface as an interface of the tagged VLAN;
The control device according to supplementary note 1 or 2.

(Additional note 4)
The control device according to any one of appendices 1 to 3, wherein the determining unit determines a new internal communication IP address for each layer 3 relay device that constitutes the virtual router.

(Appendix 5)
Topology information indicating the connection relationship between each relay device in a network configured by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device, virtual network information indicating the configuration of a virtual network including a virtual router and a virtual switch, and selected from layer 3 relay devices based on the topology information and the relay device group information stored in a storage unit that stores relay device group information indicating groups of relay devices that constitute the same virtual network. searching for a route between the core node and each layer 2 relay device;
Based on the relay device group information and the route searched by the route search unit, the shortest layer 3 relay device from each layer 2 relay device is determined, and multiple layer 2 relay devices constituting the same virtual switch If the shortest layer 3 relay devices are all the same, the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch, and multiple layer 2 relay devices that configure the same virtual switch determining the core node as the layer 3 relay device for setting the VLAN interface of the virtual switch if the shortest layer 3 relay device is different;
control methods including.

(Appendix 6)
Topology information indicating the connection relationship between each relay device in a network configured by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device, virtual network information indicating the configuration of a virtual network including a virtual router and a virtual switch, and selected from layer 3 relay devices based on the topology information and the relay device group information stored in a storage unit that stores relay device group information indicating groups of relay devices that constitute the same virtual network. a route search process that searches for a route between the core node and each layer 2 relay device;
Based on the relay device group information and the route searched by the route search unit, the shortest layer 3 relay device from each layer 2 relay device is determined, and multiple layer 2 relay devices constituting the same virtual switch If the shortest layer 3 relay devices are all the same, the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch, and multiple layer 2 relay devices that configure the same virtual switch a determination process of determining the core node as the layer 3 relay device for setting the VLAN interface of the virtual switch if the shortest layer 3 relay device is different;
A control program that causes a computer to execute.

The disclosures of the above cited patent documents, etc. are incorporated into this document by reference. Within the scope of the entire disclosure of the present invention (including the claims), changes and adjustments to the embodiments and examples are possible based on the basic technical idea thereof. Furthermore, various combinations and selections (including each element of each claim, each element of embodiments or examples, each element of each drawing, etc.) of various disclosed elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) are possible within the framework of the entire disclosure of the present invention. (including partial deletion) is possible. That is, it goes without saying that the present invention includes the entire disclosure including the claims and various modifications and modifications that a person skilled in the art would be able to make in accordance with the technical idea. In particular, numerical ranges stated herein should be construed as specifically stating any numerical value or subrange within the range, even if not otherwise stated. Furthermore, each of the disclosures in the documents cited above may be used, in part or in whole, in combination with the statements in this book as part of the disclosure of the present invention, if necessary, in accordance with the spirit of the present invention. It is deemed to be included in the disclosure of this application.

11: Control device 11-1: Relay device communication section 11-2: Topology acquisition section 11-3: Topology table 11-4: Information input section 11-5: Relay device group information storage section 11-6: Route search section 11 -7: Virtual network information storage unit 11-8: Relay device control command generation unit 21-25: Layer 2 relay devices 31-33: Layer 3 relay devices 41-49: Terminal

Claims (6)

Topology information indicating the connection relationship between each relay device in a network configured by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device, virtual network information indicating the configuration of a virtual network including a virtual router and a virtual switch, and a storage unit that stores relay device group information indicating a group of relay devices constituting the same virtual network;
a route search unit that searches for a route between a core node selected from layer 3 relay devices and each layer 2 relay device based on the topology information and the relay device group information;
Based on the relay device group information and the route searched by the route search unit, the shortest layer 3 relay device from each layer 2 relay device is determined, and multiple layer 2 relay devices constituting the same virtual switch If the shortest layer 3 relay devices are all the same, the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch, and multiple layer 2 relay devices that configure the same virtual switch a determining unit that determines the core node as a layer 3 relay device for setting a VLAN interface of the virtual switch when the shortest layer 3 relay device is different for each;
A control device having: The control device according to claim 1, wherein the determining unit allocates, to one virtual router, a layer 3 relay device that configures a VLAN interface of one or more of the virtual switches. The storage unit further stores a mapping table that associates the interface ID of the layer 2 relay device with VLAN Tag information indicating whether the interface is a tag VLAN interface,
The determining unit extracts an interface between a layer 2 relay device and the shortest layer 3 relay device for each virtual switch from the route searched by the route searching unit, and determines in the mapping table that the interface is an interface of a tagged VLAN. determining the extracted interface in addition to the identified interface as an interface of the tagged VLAN;
The control device according to claim 1 or 2. 4. The control device according to claim 1, wherein the determining unit determines a new internal communication IP address for each layer 3 relay device that constitutes a virtual router. Topology information indicating the connection relationship between each relay device in a network configured by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device, virtual network information indicating the configuration of a virtual network including a virtual router and a virtual switch, and selected from layer 3 relay devices based on the topology information and the relay device group information stored in a storage unit that stores relay device group information indicating groups of relay devices that constitute the same virtual network. searching for a route between the core node and each layer 2 relay device;
Based on the relay device group information and the searched route, the shortest layer 3 relay device from each layer 2 relay device is determined, and the shortest layer 3 relay device is determined for multiple layer 2 relay devices configuring the same virtual switch. If all the devices are the same, the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch, and the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch. If the devices are different, determining the core node as a layer 3 relay device for setting a VLAN interface of the virtual switch;
control methods including. Topology information indicating the connection relationship between each relay device in a network configured by a plurality of relay devices including a layer 2 relay device and a layer 3 relay device, virtual network information indicating the configuration of a virtual network including a virtual router and a virtual switch, and selected from layer 3 relay devices based on the topology information and the relay device group information stored in a storage unit that stores relay device group information indicating groups of relay devices that constitute the same virtual network. a route search process that searches for a route between the core node and each layer 2 relay device;
Based on the relay device group information and the searched route, the shortest layer 3 relay device from each layer 2 relay device is determined, and the shortest layer 3 relay device is determined for multiple layer 2 relay devices configuring the same virtual switch. If all the devices are the same, the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch, and the shortest layer 3 relay device is determined as the layer 3 relay device for setting the VLAN interface of the virtual switch. If the devices are different, a determination process of determining the core node as a layer 3 relay device for setting a VLAN interface of the virtual switch;
A control program that causes a computer to execute.

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