WO2014087993A1

WO2014087993A1 - Control apparatus, communication system, communication method and program

Info

Publication number: WO2014087993A1
Application number: PCT/JP2013/082457
Authority: WO
Inventors: 喜弘楠本
Original assignee: 日本電気株式会社
Priority date: 2012-12-04
Filing date: 2013-12-03
Publication date: 2014-06-12

Abstract

The present invention allows for the establishment of a packet transfer path running from the control apparatus of a centralized-control type communication system through a distributed-control type network. A control apparatus comprises: a particular link management unit that ascertains a state of the link between relay apparatuses connected via a network that is not to be controlled; a topology management unit that manages the information of a topology including the link between the relay apparatuses connected via the network that is not to be controlled; a path management unit that calculates, on the basis of the information of the topology, a packet transfer path between machines connected to the relay apparatuses and generates control information to be used for causing the relay apparatuses on the transfer path to perform packet transfers in accordance with the transfer path; and a relay apparatus communication unit that sets the control information to the relay apparatuses. The control apparatus causes, out of the relay apparatuses on the transfer path running through the network that is not to be controlled, one of two relay apparatuses, which are connected to the network that is not to be controlled, to transmit a predetermined particular link recognition packet addressed to the other of the two relay apparatuses.

Description

Control device, communication system, communication method, and program

(Description of related applications)
The present invention is based on the priority claim of Japanese patent application: Japanese Patent Application No. 2012-265328 (filed on Dec. 4, 2012), the entire contents of which are incorporated herein by reference. Shall.
The present invention relates to a control device, a communication system, a communication method, and a program, and more particularly, to a control device, a communication system, a communication method, and a program that realize communication by centrally controlling switches.

In recent years, a technique called OpenFlow has been proposed (see Non-Patent Documents 1 and 2). OpenFlow captures communication as an end-to-end flow and performs path control, failure recovery, load balancing, and optimization on a per-flow basis. The OpenFlow switch specified in Non-Patent Document 2 includes a secure channel for communication with the OpenFlow controller, and operates according to a flow table that is appropriately added or rewritten from the OpenFlow controller. For each flow, a set of match conditions (Match Fields), flow statistical information (Counters), and instructions (Instructions) that define processing contents are defined for each flow (non-patented). (Refer to “4.1 Flow Table” in Document 2).

For example, when the OpenFlow switch receives a packet, the OpenFlow switch searches the flow table for an entry having a matching condition (see “4.3 Match Fields” in Non-Patent Document 2) that matches the header information of the received packet. If an entry that matches the received packet is found as a result of the search, the OpenFlow switch updates the flow statistical information (counter) and processes the processing (designated) in the instruction field of the entry for the received packet. Perform packet transmission, flooding, discard, etc. from the port. On the other hand, if no entry matching the received packet is found as a result of the search, the OpenFlow switch sends an entry setting request to the OpenFlow controller via the secure channel, that is, a control for processing the received packet. An information transmission request (Packet-In message) is transmitted. The OpenFlow switch receives a flow entry whose processing content is defined and updates the flow table. As described above, the OpenFlow switch performs packet transfer using the entry stored in the flow table as control information.

Patent Document 1 discloses a plurality of data communication networks including a plurality of interconnected network elements, at least one of which is a centrally managed network and at least one of which is a distributed management network. According to the same document, when the control information of each network is communicated in the network by each network control channel means, the centralized management protocol and the distributed management are configured by making the connection form related to the control channel of each network different. Supporting both protocols, it is said that it becomes possible to realize two pseudo-parallel data communication networks, one for centralized management and the other for distributed management.

JP-T-2004-524784

The following analysis is given by the present invention. In addition to the OpenFlow networks described in Non-Patent Documents 1 and 2 above, there is a known network in which routers and switches on a network determine a packet transfer destination using a routing table or a MAC (Media Access Protocol) address table. Yes. Hereinafter, the OpenFlow networks of Non-Patent Documents 1 and 2 are referred to as “centralized control type networks”, and a method in which routers and switches of the network perform path control is referred to as “distributed control type networks”.

In an environment where a centralized control type network and a distributed control type network coexist, the control device of the centralized control type network cannot grasp the communication state and behavior of the distributed control type network. For this reason, there is a problem that a route passing through a distributed control type network cannot be used. In addition, even if a route through a distributed control network is set, depending on the behavior of the device outside the control target on the corresponding route, the packet may be discarded or transferred to an unintended destination. There is a problem that packets cannot be transferred.

The present invention can set a packet transfer path through a distributed control type network ("network not to be controlled" from the viewpoint of a control device) in a centralized control type communication system represented by the above-described OpenFlow. It is an object of the present invention to provide a control device, a communication system, a communication method, and a program that contribute to effective use of existing network resources.

According to the first aspect, among the relay devices to be controlled, a specific link management unit that grasps a link state between relay devices that are connected via a non-control target network, and collected from the relay devices to be controlled A topology management unit that manages topology information including a link between relay devices that are connected via the network other than the control target based on the information, and a packet between machines that are connected to the relay device based on the topology information A path management unit that calculates a transfer path and generates control information for causing the relay apparatus on the transfer path to perform packet transfer according to the transfer path; and a relay apparatus communication unit that sets the control information in the relay apparatus And one of the relay devices connected to the non-control target network among the relay devices on the transfer path that passes through the non-control target network. Provided by the control device that transmits a predetermined specific link confirmation packet to the other relay device, and causes the relay device on the transfer route passing through the non-control target network to perform packet transfer according to the transfer route. Is done.

According to the second aspect, among the relay devices to be controlled, a specific link management unit that grasps a link state between relay devices that are connected via a non-control target network, and collected from the relay devices to be controlled A topology management unit that manages topology information including a link between relay devices that are connected via the network other than the control target based on the information, and a packet between machines that are connected to the relay device based on the topology information A path management unit that calculates a transfer path and generates control information for causing the relay apparatus on the transfer path to perform packet transfer according to the transfer path; and a relay apparatus communication unit that sets the control information in the relay apparatus A control device comprising:
A plurality of relay devices arranged across the non-control target network and operating according to the control information set by the control device, the control device on a transfer path via the non-control target network Of a relay device connected to the non-control target network from one of the relay devices to the other relay device and transmitting a predetermined specific link confirmation packet on the transfer route via the non-control target network A communication system is provided in which the relay apparatus performs packet transfer according to the transfer path.

According to the third aspect, among the relay devices to be controlled, a specific link management unit that grasps a link state between relay devices that are connected via a non-control target network, and collected from the relay devices to be controlled A topology management unit that manages topology information including a link between relay devices that are connected via the network other than the control target based on the information, and a packet between machines that are connected to the relay device based on the topology information A path management unit that calculates a transfer path and generates control information for causing the relay apparatus on the transfer path to perform packet transfer according to the transfer path; and a relay apparatus communication unit that sets the control information in the relay apparatus A relay that connects to the non-controllable network among relay devices on a transfer path that passes through the non-controllable network. Transmitting a predetermined specific link confirmation packet from one of the devices to the other relay device, and forwarding the packet along the transfer route to the relay device on the transfer route passing through the non-control target network. A communication method is provided. This method is linked to a specific machine called a control device that controls a relay device by setting control information.

According to the fourth aspect, among the relay devices to be controlled, a specific link management unit that grasps a link state between relay devices connected via a network that is not controlled, and collected from the relay devices to be controlled A topology management unit that manages topology information including a link between relay devices that are connected via the network other than the control target based on the information, and a packet between machines that are connected to the relay device based on the topology information A path management unit that calculates a transfer path and generates control information for causing the relay apparatus on the transfer path to perform packet transfer according to the transfer path; and a relay apparatus communication unit that sets the control information in the relay apparatus Among the relay devices on a transfer path that passes through the non-control target network. A process of transmitting a predetermined specific link confirmation packet from one of the relay apparatuses connected to the work to the other relay apparatus, and a relay apparatus on a transfer path that passes through the network other than the control target. And a program for executing the packet transfer according to the above. This program can be recorded on a computer-readable (non-transient) storage medium. That is, the present invention can be embodied as a computer program product.

According to the present invention, in a centralized control type communication system, it is possible to set a packet transfer path that passes through a distributed control type network (“network not subject to control” as seen from the control device). As a result, it is possible to contribute to the effective use of existing network resources.

It is a figure which shows the structure of the communication system of the 1st Embodiment of this invention. It is a figure which shows the structural example of the control apparatus of the communication system of the 1st Embodiment of this invention. It is a figure which shows the structural example of the topology table (before topology collection) of the control apparatus of the communication system of the 1st Embodiment of this invention. It is a figure which shows the structural example of the legacy management table of the control apparatus of the communication system of the 1st Embodiment of this invention. It is a figure which shows the structural example of the legacy link management table of the control apparatus of the communication system of the 1st Embodiment of this invention. It is a flowchart for demonstrating the topology construction operation | movement of the control apparatus of the communication system of the 1st Embodiment of this invention. 5 is a flowchart showing an operation of a control device when information related to a legacy network is set in the communication system according to the first exemplary embodiment of the present invention. FIG. 8 is a continuation diagram of FIG. 7. It is a figure which shows the example of the control information (flow entry) which the control apparatus of the communication system of the 1st Embodiment of this invention produces | generates. It is a flowchart for demonstrating the topology update operation | movement of the control apparatus of the communication system of the 1st Embodiment of this invention. It is a figure which shows the structural example of the topology table (after topology update) of the control apparatus of the communication system of the 1st Embodiment of this invention. It is another flowchart for demonstrating the topology update operation | movement of the control apparatus of the communication system of the 1st Embodiment of this invention. It is a flowchart for demonstrating the transfer operation | movement of the user packet in the communication system of the 1st Embodiment of this invention. It is an example of the control information (flow entry) set to the relay apparatus 1103 by the control apparatus of the communication system of the 1st Embodiment of this invention. It is an example of the control information (flow entry) set to the relay apparatus 1104 by the control apparatus of the communication system of the 1st Embodiment of this invention. It is a figure which shows the transfer path | route implement | achieved by the control information (flow entry) set to the relay apparatus 1103 and the relay apparatus 1104 by the control apparatus of the communication system of the 1st Embodiment of this invention. It is a figure which shows the structure of the communication system of the 2nd Embodiment of this invention. It is another figure which shows the structure of the communication system of the 2nd Embodiment of this invention. It is another figure which shows the structure of the communication system of the 2nd Embodiment of this invention. It is a figure which shows the structure of the communication system of the 3rd Embodiment of this invention. It is a figure which shows the structure of the communication system of the 4th Embodiment of this invention. It is a figure which shows the structure of the communication system of the 5th Embodiment of this invention.

[First Embodiment]
Next, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram illustrating a configuration of a communication system according to a first embodiment of this invention. Referring to FIG. 1, control information (flow entry) is set in the legacy network 1200 including the

relay devices

1106 and 1107, the

relay devices

1103 and 1104 connected to the legacy network 1200, and the

relay devices

1103 and 1104. Thus, a configuration including the control device 100 that controls the

relay devices

1103 and 1104 is shown. Further,

terminal apparatuses

1102 and 1105 are connected to the

relay apparatuses

1103 and 1104, respectively. In addition, a maintenance terminal 1101 for managing legacy information and the like held by the control device 100 is connected to the control device 100.

1, a solid line in the figure indicates a transfer channel for transferring user data and the like, and a broken line in the figure indicates a control channel for sending and receiving control messages. Further, symbols P1 to P4 given in boxes indicating

relay apparatuses

1103, 1104, 1106, and 1107 represent port numbers of the respective relay apparatuses.

The

relay apparatuses

1103 and 1104 can be configured with devices such as the open flow switches of Non-Patent Documents 1 and 2 that operate according to control information set by the control apparatus 100.

The

relay devices

1106 and 1107 are devices such as L2 switches that are not controlled by the control device 100. For example, the

relay devices

1106 and 1107 hold an address table in which ports and destination L2 addresses are associated, and ports corresponding to L2 addresses of received packets Send a packet from The

relay apparatuses

1106 and 1107 perform a destination learning operation on the address table when receiving a packet. The legacy network 1200 includes a relay device that is not a control target, such as the L2 switch, and is not subjected to control from the control device 100.

The

terminal devices

1102 and 1105 are various terminal devices used by the user. In the present embodiment, an example of realizing communication between the

terminal devices

1102 and 1105 will be described. However, a device other than the terminal device may be a communication partner. For example, the terminal device may communicate with various servers or may be so-called M2M communication between machines.

FIG. 2 is a diagram illustrating a configuration example of the control device 100. Referring to FIG. 2, the relay device communication unit 101, the topology management unit 102, the topology table 103, the maintenance terminal communication unit 104, the legacy management unit 105, the legacy management table 106, the legacy link management unit 107, A configuration including a legacy link management table 108 and a path management unit 109 is shown.

The relay device communication unit 101 sends and receives messages such as control information (flow entry) settings for the

relay devices

1103 and 1104 and control information (flow entry) setting requests from the

relay devices

1103 and 1104. The relay device communication unit 101 instructs the

relay devices

1103 and 1104 to transmit a topology confirmation packet, and receives a response packet for the topology confirmation packet from the

relay devices

1103 and 1104. For the exchange of messages with the

relay apparatuses

1103 and 1104, the OpenFlow protocol of Non-Patent Document 2 can also be used.

The topology management unit 102 manages the topology table 103 shown in FIG. 3 based on the transmission result of the topology confirmation packet by the

relay apparatuses

1103 and 1104. The update process of the topology table 103 will be described in detail later.

The maintenance terminal communication unit 104 transmits an input screen for legacy connection port information and legacy identification information to the maintenance terminal 1101. When receiving the input of the legacy connection port information and the legacy identification information from the user, the maintenance terminal communication unit 104 transfers them to the legacy management unit 105.

The legacy management unit 105 manages information on legacy networks connected to the

relay apparatuses

1103 and 1104 that are controlled by the control apparatus 100.

FIG. 4 is a diagram illustrating a configuration example of the legacy management table 106. The legacy management table 106 of FIG. 4 includes identification information of the legacy network (here, “1200” as the code of the legacy network), an identification VLAN (Virtual Local Area Network) ID, and the control device 100's ID. An entry for storing an entry that associates the connection ports of the

relay apparatuses

1103 and 1104 to be controlled is stored. In the example of FIG. 4, a value of “3000” is set as the identification VLAN (ID), and the port P2 of the relay device 1103 and the port P2 of the relay device 1104 are set as connection ports as shown in FIG. Is set. That is, the entry of FIG. 4 indicates that the legacy network of the identification information 1200 to which the VLAN ID “3000” is assigned is connected to the port P2 of the relay apparatus 1103 and the port P2 of the relay apparatus 1104.

When a new entry is added to the legacy management table 106 or an existing entry is changed as described above, the legacy link management unit 107 reads the connection port information from the corresponding entry in the legacy management table 106 to obtain the legacy network. Information on connection links (hereinafter referred to as “legacy links”). The legacy link management unit 107 corresponds to the specific link management unit described above. The legacy link can also be referred to as a “virtual link (specific link) between relay apparatuses connected via a legacy network”.

FIG. 5 is a diagram illustrating a configuration example of the legacy link management table 108. In the legacy link management table 108 in FIG. 5, for each connection port read from the legacy management table 106, an entry for storing an entry in which the MAC address (Media Access Control Address) of the port and the connection state are associated is stored. ing. The MAC addresses of the

relay apparatuses

1103 and 1104 can be obtained by inquiring the

relay apparatuses

1103 and 1104, and the connection state can be detected based on the transmission result of the specific link confirmation packet described later.

The route management unit 109 refers to the topology table 103 and the legacy management table 106 to calculate and manage a route between relay devices under its own device. Further, the route management unit 109 generates control information for causing the relay device on the calculated route to perform packet transfer along the route, and causes the relay device communication unit 101 to set the control information. .

The control device 100 described above can be realized with a configuration in which a legacy network management function, a route setting function via the legacy network, and the like are added based on the OpenFlow controllers of Non-Patent Documents 1 and 2. 2 can also be realized by a computer program that causes a computer constituting the control device 100 to execute the above-described processes using the hardware thereof.

Subsequently, the operation of the present embodiment will be described in detail with reference to the drawings.

(Topology construction)
First, the topology construction operation of the control device 100 will be described. FIG. 6 is a flowchart for explaining the topology collection operation of the control device 100.

Referring to FIG. 6, first, the control device 100 instructs the

relay devices

1103 and 1104 to transmit a topology confirmation packet from each port (STEP 1). As the topology confirmation packet, a packet of a routing protocol such as LLDP (Link Layer Discovery Protocol) or OSPF (Open Shortest Path First) can be used. Further, for example, a packet-out message of Non-Patent Document 2 can be used as a packet output instruction from the control apparatus 100 to the

relay apparatuses

1103 and 1104.

On the other hand, when the

relay devices

1103 and 1104 receive these topology confirmation packets from other relay devices, they notify the control device 100 that these topology confirmation packets have been received and their reception ports ( (Step 2). In addition, for example, the Packet-In message of Non-Patent Document 2 can be used to report a received packet from the

relay apparatuses

1103 and 1104 to the control apparatus 100.

Based on the information from the

relay apparatuses

1103 and 1104 that have received the topology confirmation packet, the control apparatus 100 recognizes that the relay apparatuses that have exchanged the topology confirmation packet are connected, and obtains the topology information. Generate (STEP 3). FIG. 3 shows a state after the transmission of the topology confirmation packet. As shown in FIG. 1, the topology confirmation packets transmitted from the ports P1 and P2 of the

relay apparatuses

1103 and 1104 are received by the

terminals

1102 and 1105 or the

relay apparatuses

1106 and 1107 of the legacy network. Since these devices do not transmit the reception confirmation of the topology confirmation packet to the control device 100, the control device 100 sets “no” for the relay devices adjacent to each port of each relay device.

Next, the control device 100 records the topology information generated in STEP 3 in the topology table 103 (STEP 4).

(Obtaining legacy network information)
Next, the legacy network information acquisition operation of the control device 100 will be described. 7 and 8 are flowcharts showing the operation of the control device 100 when information about the legacy network is set by the user.

Referring to FIG. 7, first, the user designates legacy identification information, identification VLAN, and connection port information via the maintenance terminal 1101 (STEP 11). Here, as shown in FIG. 4, it is assumed that legacy identification information = 1200, identification VLAN = 3000, connection port information = 1103, P2, and 1104, P2.

The control device 100 that has received the information transmitted from the maintenance terminal 1101 records the information in the legacy management table 106 shown in FIG. 4 (STEP 12).

Next, the control device 100 acquires the MAC address of the port specified in the connection port information of the entry newly registered in the legacy management table 106 from the corresponding relay devices 1103 and 1104 (STEP 13). Next, the control device 100 records these pieces of information in the legacy link management table 108 shown in FIG. 5 (STEP 14). Here, the MAC address (MAC-A) of the port P2 of the relay apparatus 1103 and the MAC address (MAC-B) of the port P2 of the relay apparatus 1104 are acquired and correspond to the port information as shown in FIG. Shall be recorded.

Next, the control device 100 creates control information instructing the discard of the packet from the port connected to the legacy network (STEP 15 in FIG. 8).

FIG. 9 is an example of control information created based on the entries in the legacy link management table 108 shown in FIG. The upper part of FIG. 9 shows an example of control information set in the relay apparatus 1103. Also, the control information in FIG. 9 is arranged in order from the lowest priority. Therefore, when the relay apparatus 1103 receives a packet whose source MAC address (SMAC) is MAC-B (MAC address of the port P2 of the relay apparatus 1104) from the port P2, the relay apparatus 1103 performs an operation of discarding the packet. Further, the control information in which the match condition is “none” defines the processing contents to be executed when the priority does not match any of the higher-order control information. For this reason, the relay apparatus 1103 performs an operation of discarding other packets even when receiving other packets from the port P2.

Similarly, the lower part of FIG. 9 shows an example of control information set in the relay apparatus 1104. When the relay apparatus 1104 receives a packet whose source MAC address (SMAC) is MAC-A (MAC address of the port P2 of the relay apparatus 1103) from the port P1, the relay apparatus 1104 performs an operation of discarding the packet. Further, since the relay device 1104 is also provided with control information indicating that the match condition is “none”, the relay device 1104 performs an operation of discarding the packet even when receiving another packet from the port P2.

Next, the control device 100 sets the control information created as described above in the relay devices 1103 and 1104 (STEP 16 in FIG. 8).

(Topology update using legacy network information)
Next, a topology update operation using the legacy network information in the control apparatus 100 will be described. FIG. 10 is a flowchart for explaining the topology update operation by the control device of this embodiment.

The control device 100 instructs the

relay devices

1103 and 1104 to transmit a specific link confirmation packet from each legacy connection port (STEP 21). As the specific link confirmation packet, a packet similar to the above-described topology confirmation packet can be used. Further, the

relay devices

1106 and 1107 in the legacy network learn the address table by using the specific link confirmation packet. Note that aging processing of the address table may be performed in the

relay devices

1106 and 1107 in the legacy network. For this reason, it is desirable that the control device 100 periodically executes the series of processes in FIG. 10 at predetermined intervals.

On the other hand, when receiving the specific link confirmation packet from another relay apparatus via the legacy network 1200, the

relay apparatuses

1103 and 1104 discard the specific link confirmation packet according to the control information set in STEP 16 of FIG. . The control device 100 confirms that the specific link confirmation packet has been discarded by inquiring of the

relay devices

1103 and 1104 whether or not the specific link confirmation packet has been discarded (STEP 22).

As a result of the confirmation, when it is confirmed that the specific link confirmation packet is discarded as scheduled, the control device 100 confirms that the relay device 1103 and the relay device 1104 are connected via the legacy network 1200. Recognize (STEP 23).

Then, the control device 100 updates the topology table 103 (STEP 24). FIG. 11 is a diagram illustrating the updated topology table. Referring to FIG. 11, the adjacent relay device 1104 and its port information P2 are additionally recorded as link information of the port P2 of the relay device 1103. Similarly, the adjacent relay device 1103 and its port information P2 are additionally recorded as the link information of the port P2 of the relay device 1104.

Here, the operation when it is not confirmed in STEP 22 in FIG. 10 that the specific link confirmation packet has been discarded will be described.

FIG. 12 is a flowchart for explaining the operation when it is not possible to confirm that the specific link confirmation packet has been discarded. STEPs 21 and 22 in FIG. 12 are the same as STEPs 21 and 22 in FIG. As a result of the confirmation in STEP 22, if it cannot be confirmed that the specific link confirmation packet has been discarded, the control device 100 recognizes that the link between the relay device 1103 and the relay device 1104 has been disconnected (STEP 33).

Then, the control device 100 updates the topology table 103 (STEP 34). As shown in FIG. 3, the content after the update is in a state in which the adjacent relay device and its port information are deleted from the link information of the port P2 of the relay device 1103 and the port P2 of the relay device 1104.

(User packet transfer)
Subsequently, a transfer operation of a user packet (data packet) performed using the topology grasped as described above will be described. FIG. 13 is a flowchart for explaining a user packet transfer operation in the communication system according to the first embodiment of this invention.

Referring to FIG. 13, first, the terminal device 1102 (1105) transmits a packet addressed to the terminal device 1105 (1102) (hereinafter referred to as “user packet”). When the relay device 1103 (1104) receives the user packet, the relay device 1103 (1104) searches the control information set by the control device 100 for control information having a matching condition that matches the user packet. As shown, control information for processing user packets is not set. Therefore, the relay device 1103 (1104) transfers the user packet to the control device 100 and requests setting of control information. When receiving the user packet from the relay device 1103 (1104) (STEP 41), the control device 100 refers to the topology table 103 and calculates a transfer path for transferring the user packet to the destination (STEP 42).

Since the overall topology including the legacy network is grasped as shown in FIG. 4 by the construction and update of the topology described above, the control device 100, for example, transmits the packet from the terminal device 1102 to the relay device 1103, A route to be transferred to the terminal device 1105 in the order of the legacy network 1200 and the relay device 1104 is calculated.

Next, the control device 100 generates control information for causing the relay device on the calculated transfer route to perform packet transfer along the transfer route (STEP 43). For example, the control device 100 sets control information that causes the relay device 1103 to transfer the packet from the terminal device 1102 from the port P2. In addition, the control device 100 sets control information that causes the relay device 1104 to transfer a packet addressed to the terminal device 1105 received from the port P2 (legacy network) from the port P1.

Next, the control device 100 sets the generated control information in the

relay devices

1103 and 1104 on the transfer path (STEP 44). Further, the control device 100 instructs the relay device 1104 to output the packet received from the relay device 1103 in STEP 41 (STEP 45).

As described above, the packet transmitted from the terminal apparatus 1102 to the terminal 1105 is transferred to the terminal 1105 according to the control information set in the

relay apparatuses

1103 and 1104.

FIG. 14 is an example of control information set in the relay apparatus 1103. The entry described as “added” on the left side of FIG. 14 is control information added to process a user packet. In the third entry from the top, a match condition is set such that the source MAC address (SMAC) is the MAC address of the terminal device 1102 and the destination MAC address (DMAC) is the MAC address of the terminal device 1105. . For packets that match this match condition, SMAC is changed to MAC-A (MAC address of port P2 of relay apparatus 1103), DMAC is changed to MAC-B (MAC address of port P2 of relay apparatus 1104), VLAN An action (Action) for performing a process of transferring from the port P2 after giving the ID 3000 is described. In the example of FIG. 14, control information for processing a response packet addressed to the terminal 1102 from the terminal device 1105 is also set. The fourth entry from the top restores SMAC and DMAC for each packet that matches the match condition where the destination MAC address (DMAC) is MAC-A (the MAC address of port P2 of the relay device 1103), and the VLAN ID. In addition, an action (Action) for performing a process of transferring from port P2 is described.

FIG. 15 is an example of control information set in the relay device 1104. The entry described as “added” on the left side of FIG. 15 is control information added to process the user packet. The third entry from the top is control information for processing a response packet addressed to the terminal 1102 from the terminal device 1105. Specifically, a match condition is set such that the source MAC address (SMAC) is the MAC address of the terminal device 1105 and the destination MAC address (DMAC) is the MAC address of the terminal device 1102. For packets that match this match condition, SMAC is changed to MAC-B (MAC address of port P2 of relay apparatus 1104), DMAC is changed to MAC-A (MAC address of port P2 of relay apparatus 1103), VLAN An action (Action) for performing a process of transferring from the port P2 after giving the ID 3000 is described. The fourth entry from the top is control information for processing a packet addressed to the terminal 1105 from the terminal device 1102, and the destination MAC address (DMAC) is MAC-B (the MAC address of the port P2 of the relay device 1104). An action (Action) for restoring the SMAC and the DMAC and deleting the VLAN ID and transferring the packet from the port P2 is described.

As a result, bidirectional packet transfer via the legacy network 1200 is realized as shown in FIG. Then, for example, the packet addressed to the terminal 1105 transmitted from the terminal device 1102 is subjected to MAC rewriting so that the packet is correctly transferred in the legacy network in the ingress relay device 1103, and is transmitted to the egress relay device 1104. And restored. As shown in FIGS. 13 and 14, the number of control information entries to be set in each relay apparatus is two, and an inquiry to the control apparatus 100 (control information setting request) is also received at the first packet reception. Therefore, the load on the control device 100 and the

relay devices

1103 and 1104 is not increased, and the resource usage is not increased.

Subsequently, second to fifth embodiments of the present invention will be described. The second to fifth embodiments of the present invention are different from each other in the arrangement relationship between the network in which the relay apparatus controlled by the control apparatus 100 and the first embodiment and the network (legacy network) that is not the first embodiment are arranged. Therefore, there is no particular change in the configuration of the control device 100. Hereinafter, the difference will be mainly described.

[Second Embodiment]
FIG. 17 is a diagram showing a configuration of a communication system according to the second exemplary embodiment of the present invention. A difference from the first embodiment shown in FIG. 1 is that

networks

1310 and 1320 in which relay devices controlled by the control device 100 are arranged are arranged at both ends of the legacy network 1200, and the terminal devices 1001 to 1004 are arranged. It is a point to communicate via these.

FIG. 18 is a diagram showing a network topology grasped by transmitting a topology confirmation packet as in the first embodiment. As illustrated in FIG. 18, the relay device 1103 of the first embodiment is two

relay devices

1010 and 1011, the relay device 1104 of the first embodiment is two

relay devices

1018 and 1019, Only the terminal devices 1001 to 1004 are connected to each other, and there is no difference in the basic configuration.

FIG. 19 is a diagram showing a network topology that is grasped by transmitting a specific link confirmation packet, as in the first embodiment. By transmitting the specific link confirmation packet, the relay apparatuses 1071 to 1076 learn the correspondence between the respective ports and the MAC addresses of the legacy connection ports of the

relay apparatuses

1010, 1011, 1018, and 1019. Further, the control device 100 grasps the state of the link between the

relay devices

1010, 1011, 1018, and 1019. As a result, as in the first embodiment, the relay device on the entrance side of the legacy network is set with the control information to be transferred to the legacy network after rewriting the necessary headers. Control information to be transferred after restoring the header is set in the relay device. As a result, the packets between the terminal devices 1001 to 1004 are rewritten (restored) in the headers by the relay devices each having a connection port with the legacy network, and after exceeding the legacy network, according to the instruction of the control device 100, Transferred to the destination communication terminal.

As described above, the present invention is not limited to the configuration in which the terminal device and the relay device illustrated in FIG. 1 are arranged one-on-one, and there are a plurality of relay devices under control of the control device 100, each of which is a terminal device. It can also be applied to a network configuration in which are connected.

[Third Embodiment]
FIG. 20 is a diagram showing a configuration of a communication system according to the third exemplary embodiment of the present invention. The difference from the second embodiment shown in FIG. 17 is that there are a plurality of legacy networks and a plurality of

legacy networks

1200 and 1210 exist. This configuration can also be viewed as a configuration in which the configuration of the first embodiment is connected in parallel. This configuration has an advantage that the control device 100 can select which of the

legacy networks

1200 and 1210 is used to transfer the user packet. For example, the packet between the terminal apparatuses 1001 to 1003 can be transferred via the legacy network 1200, and the packet between the terminal apparatuses 1002 to 1004 can be transferred via the legacy network 1210. Further, for example, it is possible to operate such that both the packet between the terminal devices 1001 to 1003 and the packet between the terminal devices 1002 to 1004 are transferred via the legacy network 1200 and the legacy network 1210 is suspended.

[Fourth Embodiment]
FIG. 21 is a diagram showing a configuration of a communication system according to the fourth exemplary embodiment of the present invention. The difference from the third embodiment shown in FIG. 20 is that there is no legacy network 1210 and the network 1310 and the network 1320 are directly connected. In this configuration, this configuration has an advantage that the control device 100 can select whether or not to transfer the user packet using the legacy network 1200.

[Fifth Embodiment]
FIG. 22 is a diagram showing a configuration of a communication system according to the fifth exemplary embodiment of the present invention. The difference from the third embodiment shown in FIG. 20 is that the legacy network 1210 is located on the outside of the network 1310 and the network 1330 in which the relay device that can be controlled by the control device is located on the outside. It is a point.

Also in the present embodiment, address learning is performed in the relay apparatuses on the

legacy networks

1200 and 1210 by transmission of the specific link confirmation packet, and the link between the relay apparatuses belonging to the networks 1310-1320 by the control apparatus 100 and the network 1320 is also performed. The status of the link between relay devices belonging to -1330 is ascertained. For this reason, as in the first embodiment, by setting control information instructing necessary header rewriting and packet transfer from the control device 100, packets are transferred via the two

legacy networks

1200 and 1210. be able to.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and further modifications, substitutions, and adjustments may be made without departing from the basic technical idea of the present invention. Can be added. For example, the number of relay devices and terminal devices used in the above embodiment and the network configuration are merely examples, and various modifications can be made.

In the above-described embodiment, the relay device of the legacy network has been described as an L2 switch. However, in other distributed control type networks such as an L3 switch that transfers packets based on FIB (Forwarding Information DataBase) or the like. It may be a device used.

Finally, a preferred form of the invention is summarized.
[First embodiment]
(Refer to the control device according to the first viewpoint)
[Second form]
In the control device of the first form,
The specific link management unit holds address information given to a port of a relay device connected via the network not controlled,
By transmitting a packet in which the address assigned to the port of the relay device is set to the transmission source and the destination as the specific link confirmation packet, the address and port are transmitted to the relay device arranged in the non-control target network. A control device that learns the correspondence relationship between
[Third embodiment]
In the control device of the second form,
For data packets that pass on a transfer path that passes through the network that is not controlled,
Causing the relay device in front of the non-control target network to perform header rewriting with the address given to the port of the relay device located beyond the non-control target network as the destination,
By causing the relay device in a position beyond the network not to be controlled to perform the process of restoring the rewritten header,
A control device that causes a relay device on a transfer path that passes through the non-control target network to perform packet transfer according to the transfer path.
[Fourth form]
In the control device of the third aspect,
For data packets that pass on a transfer path that passes through the network that is not controlled,
Have the relay device in front of the non-control target network perform header rewriting with the address given to the port connected to the non-control target network as the transmission source,
A control device that causes a relay device located beyond a non-control target network to perform a process of restoring a transmission source in the rewritten header.
[Fifth embodiment]
In the control device of the fourth form,
For data packets that pass on a transfer path that passes through the network that is not controlled,
Causing the relay device in front of the non-controllable network to perform header rewriting to add predetermined VLAN information;
A control device that causes a relay device located beyond a network that is not controlled to perform processing for restoring VLAN information in the rewritten header.
[Sixth embodiment]
In the control device according to any one of the first to fifth aspects,
When it is determined from the transmission result of the specific link confirmation packet that the link between the relay devices connected via the network not to be controlled is in a disconnected state, the topology information managed by the topology management unit is updated. Control device.
[Seventh form]
In the control device according to any one of the second to sixth aspects,
The specific link management unit uses a table that stores an entry that associates a port of a relay device connected via the network not controlled, an address assigned to the port, and a link state, A control device that manages a link state and an address between relay devices connected via a network other than the control target.
[Eighth form]
(Refer to the communication system according to the second viewpoint)
[Ninth Embodiment]
(Refer to the communication method according to the third viewpoint)
[Tenth embodiment]
(Refer to the program from the fourth viewpoint above.)
Note that the eighth to tenth embodiments can be developed into the second to seventh embodiments as in the first embodiment.

It should be noted that the disclosures of the above patent documents and non-patent documents are incorporated herein by reference. Within the scope of the entire disclosure (including claims) of the present invention, the embodiments and examples can be changed and adjusted based on the basic technical concept. Further, various combinations or selections of various disclosed elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) within the scope of the claims of the present invention. Is possible. That is, the present invention of course includes various variations and modifications that could be made by those skilled in the art according to the entire disclosure including the claims and the technical idea. In particular, with respect to the numerical ranges described in this document, any numerical value or small range included in the range should be construed as being specifically described even if there is no specific description.

DESCRIPTION OF SYMBOLS 100 Control apparatus 101 Relay apparatus communication part 102 Topology management part 103 Topology table 104 Maintenance terminal communication part 105 Legacy management part 106 Legacy management table 107 Legacy link management part 108 Legacy link management table 109 Path management part 1101 Maintenance terminals 1001 to 1004, 1102 1105

Terminal device

1010, 1011, 1018, 1019, 1103, 1104 Relay device 1071-1076, 1106, 1107 Relay device (L2)
1200, 1210 Legacy network 1300-1330 Network P1-P4 Port number

Claims

Among the relay devices to be controlled, a specific link management unit that grasps the state of the link between relay devices connected via a network that is not controlled,
A topology management unit that manages topology information including a link between relay devices connected via the non-control target network based on information collected from the control target relay device;
Route management that calculates a packet transfer path between machines connected to the relay device based on the topology information and generates control information for causing the relay device on the transfer route to perform packet transfer according to the transfer route And
A relay device communication unit that sets the control information in the relay device,
Among relay devices on a transfer path that passes through the non-control target network, one of relay devices connected to the non-control target network is addressed to the other relay device, and a predetermined specific link confirmation packet is transmitted. Causing a relay device on a transfer path through the network outside the control target to perform packet transfer according to the transfer path;
A control device characterized by.
The specific link management unit holds address information given to a port of a relay device connected via the network not controlled,
By transmitting a packet in which the address assigned to the port of the relay device is set to the transmission source and the destination as the specific link confirmation packet, the address and port are transmitted to the relay device arranged in the non-control target network. The control apparatus according to claim 1, wherein learning of the correspondence relationship between the two and the like is performed.
For data packets that pass on a transfer path that passes through the network that is not controlled,
Causing the relay device in front of the non-control target network to perform header rewriting with the address given to the port of the relay device located beyond the non-control target network as the destination,
By causing the relay device in a position beyond the network not to be controlled to perform the process of restoring the rewritten header,
The control apparatus according to claim 2, wherein a relay apparatus on a transfer path that passes through the non-control target network performs packet transfer according to the transfer path.
For data packets that pass on a transfer path that passes through the network that is not controlled,
Have the relay device in front of the non-control target network perform header rewriting with the address given to the port connected to the non-control target network as the transmission source,
The control apparatus according to claim 3, wherein a relay apparatus located at a position beyond the non-control target network performs a process of restoring the transmission source in the rewritten header.
For data packets that pass on a transfer path that passes through the network that is not controlled,
Causing the relay device in front of the non-controllable network to perform header rewriting to add predetermined VLAN information;
5. The control device according to claim 4, wherein the relay device located at a position beyond the network not to be controlled performs a process of restoring the VLAN information in the rewritten header.
When it is determined from the transmission result of the specific link confirmation packet that the link between the relay devices connected via the network not to be controlled is in a disconnected state, the topology information managed by the topology management unit is updated. The control device according to any one of claims 1 to 5.
The specific link management unit uses a table that stores an entry that associates a port of a relay device connected via the network not controlled, an address assigned to the port, and a link state, The control device according to any one of claims 2 to 6, which manages a link state and an address between relay devices connected via the non-control target network.
Among the relay devices to be controlled, a specific link management unit that grasps the state of the link between relay devices connected via a network that is not controlled,
A topology management unit that manages topology information including a link between relay devices connected via the non-control target network based on information collected from the control target relay device;
Route management that calculates a packet transfer path between machines connected to the relay device based on the topology information and generates control information for causing the relay device on the transfer route to perform packet transfer according to the transfer route And
A control device comprising: a relay device communication unit that sets the control information in the relay device;
A plurality of relay devices that are arranged across the non-control target network and operate according to control information set by the control device,
The control device is
Among relay devices on a transfer path that passes through the non-control target network, one of relay devices connected to the non-control target network is addressed to the other relay device, and a predetermined specific link confirmation packet is transmitted.
Causing a relay device on a transfer path through the network outside the control target to perform packet transfer according to the transfer path;
A communication system characterized by the above.
Among the relay devices to be controlled, a specific link management unit that grasps the state of the link between relay devices connected via a network that is not controlled,
A topology management unit that manages topology information including a link between relay devices connected via the non-control target network based on information collected from the control target relay device;
Route management that calculates a packet transfer path between machines connected to the relay device based on the topology information and generates control information for causing the relay device on the transfer route to perform packet transfer according to the transfer route And
A control device comprising a relay device communication unit that sets the control information in the relay device,
A step of transmitting a predetermined specific link confirmation packet from one of the relay devices connected to the non-control target network to the other relay device among the relay devices on a transfer path passing through the non-control target network When,
Causing a relay device on a transfer path that passes through the non-controllable network to perform packet transfer according to the transfer path.
Among the relay devices to be controlled, a specific link management unit that grasps the state of the link between relay devices connected via a network that is not controlled,
A topology management unit that manages topology information including a link between relay devices connected via the non-control target network based on information collected from the control target relay device;
Route management that calculates a packet transfer path between machines connected to the relay device based on the topology information and generates control information for causing the relay device on the transfer route to perform packet transfer according to the transfer route And
A computer comprising a control device comprising a relay device communication unit for setting the control information in the relay device;
Processing for transmitting a predetermined specific link confirmation packet from one of relay devices connected to the non-control target network to the other relay device among relay devices on a transfer path passing through the non-control target network When,
A program for causing a relay apparatus on a transfer path passing through the network not to be controlled to perform packet transfer according to the transfer path.