WO2013123846A1

WO2013123846A1 - Distributed network control method and device

Info

Publication number: WO2013123846A1
Application number: PCT/CN2013/071151
Authority: WO
Inventors: 胡永生; 汪军; 李漓春
Original assignee: 中兴通讯股份有限公司
Priority date: 2012-02-22
Filing date: 2013-01-30
Publication date: 2013-08-29
Also published as: CN102594689B; CN102594689A

Abstract

Disclosed is a distributed network control method. A plurality of controller nodes form a distributed controller network, and each controller node manages one or more exchanger devices. The method comprises: controller nodes receiving information reported by an exchanger, synchronizing network topology change information in the information among all the controller nodes, and storing host position information in the information into a distributed controller network; and when receiving a data stream processing request, the controller nodes querying destination address information about a data stream in the distributed controller network, and establishing a data exchange path for the data stream according to locally stored global network topology information. Also provided is a distributed network control device. According to the technical solution of the present invention, the performance bottleneck problem of a network controller can be solved.

Description

Distributed network control method and device

The present invention relates to the field of computer network technologies, and in particular, to a distributed network control method and apparatus. Background technique

In 2008, Stanford University proposed the OpenFlow protocol, which uses a forwarding/control separation architecture. The external control plane entity uses the OpenFlow protocol to control the forwarding plane device to implement various forwarding logics. The main function of the forwarding plane device is based on control. The forwarding flow table delivered by the polygon entity performs controlled forwarding, and its behavior is standardized: the forwarding plane device receives a packet, and extracts the L2/L3/L4 related field values of the packet header, and uses these related field values as the key. The word search forwarding flow table is matched to the entry, and the message field is transformed according to the instruction set in the content of the entry. After the transformation is completed, the flow is forwarded to a logical or physical port according to the indication. The OpenFlow protocol is further evolved into the foundation of Software Defined Network (SDN) technology, which can implement various complex network applications by using software programming on the control plane entity, without any change in the forwarding plane device. The control plane device uses a general-purpose server + general-purpose operating system, and can be implemented using a common software programming tool or a scripting language such as Python, which makes the support of the new network protocol very simple, and the new technology deployment cycle is greatly shorten. A basic OpenFlow network consists of two main control entities, the network controller and the switch. Typically, a centralized network controller is deployed in the network responsible for the management domain control of all OpenFlow switches throughout the network domain. However, a single centralized network controller can become a bottleneck for network scale. For example, the delay of establishing a flow of a switch that is far away from the network controller increases, and the throughput of a single network controller processing the exchange path request is limited. The path bandwidth of the end is poorly controllable. To this end, the academic community has proposed distributed network controller solutions, such as HyperFlow, online information exchange. (ONIX), etc., but these solutions generally deploy multiple network controllers on the network, and implement multiple states of the same network controller to manage and control the OpenFlow network through event message synchronization or storage sharing. For large-scale networks, there are tens of thousands of network events that need to be synchronized between network controllers in the above solution. The existing global event synchronization mechanism cannot meet the requirements, that is, the existing solution is not suitable for large-scale network deployment. . Summary of the invention

In view of this, the main object of the present invention is to provide a distributed network control method and device, which can solve the performance bottleneck problem of the network controller.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

The present invention provides a distributed network control method, in which a plurality of controller nodes form a distributed controller network, and each controller node manages one or more switch devices;

The controller node receives the information reported by the switch, synchronizes network topology change information in the information between all controller nodes, and saves the host location information in the information to the distributed control network;

When receiving the data stream processing request, the controller node queries the distributed controller network for the destination address information of the data stream, and establishes a data exchange path for the data stream according to the locally stored global network topology information.

In the above method, the network topology change information is synchronized between all controller nodes: the controller node synchronizes the network topology change information between all controller nodes by using an independent global event synchronization system, or utilizes The message broadcast mechanism of the distributed controller network synchronizes the network topology change information across all controller nodes.

In the above method, the method further includes: the controller node storing the synchronized network topology change information, and obtaining consistent global network topology information according to the network topology change information;

The network topology change information is: attributes of the switch, or a link state of the switch joining the network, or the switch leaving the network, or the switch. In the above method, the saving the host location information to the distributed control network is: the controller node saves the host location information to a controller node other than the local node in the distributed controller network;

The method further includes: the controller node receiving the information reported by the switch simultaneously saves the received host location information locally.

In the above method, the host location information is: a data link layer location and/or a network layer location of a host connected to the switch.

In the above method, the data link layer location is a correspondence between a MAC address of a host connected to the switch and a port identifier of the switch;

The network layer location is a correspondence between an IP address of a host connected to the switch and a port identifier of the switch, or a correspondence between the network domain identifier and a port identifier of the switch.

In the above method, the destination address information of the data stream in the distributed controller network is:

After receiving the data stream processing request, the controller node first queries the node for the destination address information of the data stream, and then queries the controller node other than the local node in the distributed control network to query the destination address information of the data stream.

In the above method, the destination address information is: a port identifier of a switch corresponding to a host MAC address and/or an IP address, or a port list information of a switch corresponding to the network domain identifier.

The present invention also provides a distributed network control device, which is a controller node, and the controller node includes: a control module, an event synchronization module, and a distributed processing module;

The control module is configured to receive the information reported by the switch, and is further configured to receive the data stream processing request, and after the distributed processing module queries the destination address of the data stream, establish data for the data stream according to the locally stored global network topology information. Exchange path

An event synchronization module, configured to synchronize network topology change information in the information reported by the switch between all controller nodes; a distributed processing module, configured to save host location information in the information reported by the switch to the distributed control network; and, after receiving the data stream processing request, querying the data flow in the distributed controller network Address information.

In the above device, the device further comprises:

The information storage module is configured to save synchronized network topology change information, and/or received host location information, and obtain consistent global network topology information according to the network topology change information.

The distributed network control method and device provided by the present invention, the controller node receives the information reported by the switch, synchronizes the network topology change information in the information between all controller nodes, and saves the host location information in the information. Going to the distributed control network; when receiving the data stream processing request, the controller node queries the distributed controller network for the destination address information of the data stream, and uses the locally stored global network topology information as the data stream. The data exchange path is established. Therefore, in the present invention, a small amount of necessary network topology information is globally synchronized, and the host related information that is frequently changed is distributed and queried by the controller node, thereby being able to adapt to the linear growth of the network scale. Solve performance bottlenecks in network controllers. DRAWINGS

1 is a schematic flow chart of a method for implementing a distributed network control according to the present invention;

2 is a diagram showing an example of networking for implementing a distributed network control method according to the present invention;

3 is a schematic flowchart of a specific implementation method of the implementation step 101 of the present invention;

4 is a schematic flow chart of a specific implementation method of the implementation step 106 of the present invention;

FIG. 5 is a schematic flowchart diagram of a specific implementation method of the implementation step 103 of the present invention;

FIG. 6 is a schematic structural diagram of a distributed network control apparatus according to the present invention. detailed description

The basic idea of the present invention is that the controller node receives the information reported by the switch, synchronizes the network topology change information among all controller nodes, and maintains the host location information therein. And storing, in the distributed control network, the controller node, when receiving the data stream processing request, querying the destination address information of the data flow in the distributed controller network, and using the locally stored global network topology information as the data The flow establishes a data exchange path.

The invention will be further described in detail below with reference to the drawings and specific embodiments.

The present invention provides a distributed network control method. FIG. 1 is a schematic flowchart of a distributed network control method according to the present invention. As shown in FIG. 1, the method includes the following steps:

Step 101: The controller node receives the network topology change information reported by the switch, and synchronizes the network topology change information between all controller nodes.

Specifically, as shown in FIG. 2, in the present invention, a plurality of controller nodes form a distributed controller network, which is a distributed network, such as a distributed hash table (DHT) of One-hop. Network; each controller node manages one or more switch devices, and multiple switches are interconnected by physical links and form a switch network;

The controller node receives the network topology change information reported by the switch managed by the switch, and the network topology change information includes: attributes of the switch, the switch joins the network, the switch leaves the network, and the link state between the switches; the controller node is at The network topology change information is synchronized in all controller nodes in the distributed controller network, and the other controller nodes save the synchronized network topology change information, so that all controller nodes can be consistent according to the network topology change information. Global network topology information.

The method for synchronizing may be through an independent global event synchronization system, for example: an event publishing system, an event subscription system, or a distributed controller network, for example: a distributed control message broadcast mechanism of its network.

Step 102: The controller node receives the host location information reported by the switch, and saves the host location information to the distributed controller network.

Specifically, the controller node receives the host location information reported by the switch managed by the controller, where the host location information includes: a data link layer location and/or a network layer connected to the host on the switch. The data link layer location refers to the medium access control of the host connected to the switch.

Correspondence between the (MAC) address and the port identifier of the switch. The network layer location refers to the correspondence between the IP address of the host connected to the switch and the port identifier of the switch, or the correspondence between the network domain identifier and the port identifier of the switch. Relationship; The controller node saves the host location information to other controller nodes in the distributed controller network. Preferably, the received host location information can also be saved locally at the same time.

Step 103: When receiving the data stream processing request, the controller node queries the distributed controller network for the destination address information of the data flow, and establishes a data exchange path for the data flow according to the locally stored global network topology information.

Specifically, when receiving the data stream processing request, the controller node queries the controller node in the distributed controller network for the destination address information of the data stream, where the controller node includes the controller node that receives the data stream processing request, And other controller nodes in the distributed control network; in order to improve the query speed, after receiving the data stream processing request, the controller node may first query the destination address information of the data stream in the node, and then in the distributed control network. The other controller node queries the destination address information of the data stream; the destination address information may be the port identifier of the switch corresponding to the host MAC address and/or the IP address, or the port list information of the switch corresponding to the network domain identifier.

The controller node selects a switching path for the data stream according to the destination address information of the queried data stream and the global network topology information stored locally, and sends a corresponding forwarding flow table to the switch device on the switching path, thereby implementing The data stream establishes a data exchange path.

3 is a schematic flowchart of a specific implementation method of the implementation step 101 of the present invention, where each controller node manages a part of the switch, in order to make the controller node reach the whole network optimal in the exchange path selected for the service, each controller node needs to have Uniform global network topology information. Therefore, each controller node needs to synchronize the network topology events that are perceived to the entire network. As shown in Figure 3, the method includes the following steps: Step 301: The switch SW1 joins the OpenFlow network.

The process of joining the OpenFlow network includes: establishing a connection with the controller node A, and performing related security verification, basic information reporting, and switch configuration operations.

Step 302: Since the switch SW1 joins the OpenFlow network, the controller node A issues a network event that the switch SW1 joins to the global event synchronization system.

The global event synchronization system is an independent event subscription system or an event issuance system; the network event that the switch SW1 joins needs to carry basic information of the switch SW1, such as the identifier of the switch SW1, port configuration information, and the like.

Step 303: The global event synchronization system synchronizes network events added by the switch SW1 in the distributed controller network, and other controller nodes in the distributed controller network learn that the switch SW1 joins the network under the controller node A.

Step 304: The switch SW1 reports the received link detection packet to the controller node A, where the network topology change information is carried.

Step 305: The controller node A determines, according to the link detection message, that a new link exists between the switch SW1 and another switch SWX. Here, the new link may be a link that is not originally discovered, or a link. The state of the road changes.

Step 306, the controller node A issues a link network event between the switch SW1 and the switch SWX to the global event synchronization system;

The link network event between the switch S W1 and the switch SWX needs to carry basic information about the link, such as the switch identifier of the switch SW1 and the switch SWX, the switch port identifier where the link is located, and the bandwidth of the link. information.

Step 307: The global event synchronization system synchronizes the link network events of the switch SW1 and the switch SWX in the distributed controller network, and the other controller nodes in the distributed controller network learn the link between the switch SW1 and the switch SWX. A change has occurred.

Step 308, controller node A finds that switch SW1 leaves the network. Step 309, the controller node A issues a network event that the switch SW1 leaves to the global event synchronization system;

The network event that the switch SW1 leaves needs to carry the basic information of the switch SW1, such as the identifier of the switch.

Step 310: The global event synchronization system synchronizes the network events that the switch SW1 leaves in the distributed controller network, and the other controller nodes in the distributed controller network learn that the switch SW1 leaves the network under the controller node A, and updates each Stored global network topology information.

In this embodiment, the synchronization of network topology change events between all controller nodes by using the global event synchronization system can also be implemented by a message broadcast mechanism of the distributed controller network.

4 is a schematic flowchart of a specific implementation method of the implementation step 106 of the present invention. The controller node learns the host location information from the data packet reported by the switch, and stores the host location information in the distributed controller network, as shown in FIG. 4 . As shown, the method includes the following steps:

Step 401: The host sends a data packet to the switch SW1 connected to the host.

Step 402: The switch SW1 receives the data packet, and after querying the local forwarding flow table, it finds that there is no corresponding entry, and therefore reports the data packet to the controller node A.

Step 403: The controller node A checks the source address of the received data packet. If the source address of the data packet is a new host or the address of the corresponding host changes, the host location information needs to be updated.

Here, controller node A may choose to store the host location information locally.

Step 404, the controller node A stores the host location information on the controller node X of the distributed controller network, and the specific storage manner is related to the mechanism of the distributed controller network, for example, the distributed controller network is a single-hop distributed For a One-hop DHT network, controller node A needs to hash the identity of the host and store it in the controller node.

In this embodiment, the host location information that needs to be stored is the MAC of the host connected to the switch. The correspondence between the address and the port identifier of the switch, or the correspondence between the IP address of the host connected to the switch and the port identifier of the switch, or the correspondence between the network domain identifier and the port identifier of the switch; the network domain identifier includes the VLAN identifier, MPLS logo, etc.

In steps 403 and 404, the host location information that needs to be stored may be stored in one or more indexes, for example, by using the host's MAC address, and/or IP address, and/or the network domain identifier as a key for storage. .

5 is a schematic flowchart of a specific implementation method of the implementation step 103 of the present invention. The host A connected to the switch SW1 is to communicate with the host B connected to the switch SW2, and the first data packet is sent by the switch SW1 to the controller node A. The controller node A queries the destination address information of the data packet through the distributed controller network, and selects and establishes an appropriate switching path according to the global network topology information. As shown in FIG. 5, the method includes the following steps:

Step 501: Host A wants to communicate with host B, and sends the first data packet to the connected switch SW1.

Step 502: After the switch SW1 queries the local forwarding flow table that there is no match, the switch reports the data packet to the controller node A, and is used to initiate a data flow processing request to the controller node A.

Step 503: The controller node A queries the other controller nodes in the distributed controller network for the destination address information of the data packet.

Here, according to the type of the data message, such as unicast, multicast, and broadcast messages, the destination address information of the data message may be an address list.

Wherein, if the storage of the host location information adopts a local storage mechanism, and the switch SW1 and the switch SW2 are switches managed by the controller node A, the controller node A does not need to search for other controller nodes in the distributed controller network. Destination address information of the data packet.

Step 504: The controller node A selects a switching path for the data packet according to the source and destination address information of the data packet and the global network topology information stored in the local network. The switching path in this embodiment is the switch SW1 and Switch SW2. Step 505: The controller node A sends the forwarding flow table of the data packet to the switch SW1. In step 506, the controller node A sends the forwarding flow table of the data packet to the switch SW2. Here, if the switch SW2 is directly connected to the controller node B, the step is:

506a, the controller node A sends the forwarding flow table to the controller node B, and the controller node B delivers the forwarding flow table to the switch SW2.

Step 507: The switch SW1 forwards the data packet according to the received forwarding flow table, where the switch forwards to the switch SW2.

Step 508: The switch SW2 forwards the data packet according to the received forwarding flow table, where the forwarding is performed to the connected host B.

To achieve the above method, the present invention further provides a distributed network control device, which is a controller node, and FIG. 6 is a schematic structural diagram of a distributed network control device according to the present invention. As shown in FIG. 6, the device includes: Module 61, event synchronization module 62, distributed processing module 63; wherein

The control module 61 is configured to receive the information reported by the switch, and is further configured to receive the data stream processing request, and after the distributed processing module queries the destination address of the data stream, according to the locally stored global network topology information, the data stream is used as the data stream. Establish a data exchange path;

The event synchronization module 62 is configured to synchronize network topology change information in the reported information between all controller nodes;

The distributed processing module 63 is configured to save the host location information in the reported information to the distributed control network, and is further configured to: after receiving the data stream processing request, query the data flow in the distributed controller network. Address information.

The device also includes:

The information storage module 64 is configured to save the synchronized network topology change information, and/or the received host location information, and obtain consistent global network topology information according to the network topology change information.

The event synchronization module 62 will use the network topology change information in all controller sections. Inter-point synchronization is: synchronizing the network topology change information between all controller nodes by using a separate global event synchronization system, or synchronizing the network topology among all controller nodes by using a message broadcast mechanism of a distributed controller network Change information. The network topology change information is: an attribute of the switch, or a link state of the switch joining the network, or the switch leaving the network, or the switch.

The distributed processing module 63 saves the host location information to the distributed control network as: saving the host location information to other controller nodes in the distributed controller network?

The host location information is: a data link layer location and/or a network layer location of a host connected to the switch. The data link layer location is a correspondence between a MAC address of a host connected to the switch and a port identifier of the switch; the network layer location is a correspondence between an IP address of the host connected to the switch and a port identifier of the switch, or a network The relationship between the domain ID and the port ID of the switch.

The destination address information of the distributed processing module 63 for querying the data flow in the distributed controller network is: after receiving the data flow processing request, first querying the destination address information of the data flow in the node, and then distributing The other controller nodes in the control network query the destination address information of the data stream. The destination address information is: a port identifier of a switch corresponding to the host MAC address and/or the IP address, or a port list information of the switch corresponding to the network domain identifier.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included. Within the scope of protection of the present invention.

Claims

Claim

A distributed network control method, characterized in that a plurality of controller nodes form a distributed controller network, and each controller node manages one or more switch devices; the method includes: the controller node receives the report reported by the switch Information, synchronizing network topology change information in the information between all controller nodes, and saving host location information in the information to a distributed control network;

2. The method according to claim 1, wherein the synchronizing network topology change information between all controller nodes is:

The controller node synchronizes the network topology change information among all controller nodes by using an independent global event synchronization system, or synchronizes the network topology among all controller nodes by using a message broadcast mechanism of a distributed controller network Change information.

3. A method according to claim 1 or 2, characterized in that

The method further includes: the controller node saves the synchronized network topology change information, and obtains a consistent global network topology information according to the network topology change information;

The network topology change information is: the attributes of the switch, or the link state of the switch joining the network, or the switch leaving the network, or the switch.

The method according to claim 1, wherein the saving the host location information to the distributed control network is: the controller node saves the host location information to a distributed controller network In a controller node other than this node;

Correspondingly, the method further includes: the controller node that receives the information reported by the switch simultaneously saves the received host location information locally.

The method according to claim 1 or 4, wherein the host location information To: Connect the data link layer location and/or network layer location of the host on the switch.

6. The method of claim 5, wherein

The data link layer location is: a correspondence between a MAC address of a host connected to the switch and a port identifier of the switch;

The network layer location is: a correspondence between an IP address of a host connected to the switch and a port identifier of the switch, or a correspondence between a network domain identifier and a port identifier of the switch.

7. The method according to claim 1, wherein the querying the destination address information of the data stream in the distributed controller network is:

The method according to claim 1 or 7, wherein the destination address information is: a port identifier of a switch corresponding to a host MAC address and/or an IP address, or a port list information of a switch corresponding to the network domain identifier. .

A distributed network control device, wherein the device is a controller node, the controller node includes: a control module, an event synchronization module, and a distributed processing module; wherein the control module is configured to receive a switch The reported information is further configured to receive the data stream processing request, and after the distributed processing module queries the destination address of the data stream, establish a data exchange path for the data stream according to the locally stored global network topology information;

The event synchronization module is configured to synchronize network topology change information in the information reported by the switch between all controller nodes;

The distributed processing module is configured to save host location information in the information reported by the switch to the distributed control network; and further, after receiving the data stream processing request, querying the data flow in the distributed controller network Destination address information.

10. The device according to claim 9, wherein the device further comprises: The information storage module is configured to save synchronized network topology change information, and/or received host location information, and obtain consistent global network topology information according to the network topology change information.