CN108540343B - Path detection method and device - Google Patents
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Abstract
The invention relates to a method and a device for detecting a path, comprising the following steps: sending a first message for detecting a communication path between the gateway device and the edge router to the gateway device, wherein the first message comprises a first path detection message, and the first path detection message is used for enabling the gateway device to forward the first path detection message subjected to NAT conversion by a next hop network device to the edge router through the next hop network device; receiving a second path detection message sent by the gateway equipment within a preset time period, wherein the second path detection message is a message forwarded to the gateway equipment by the edge router via the next hop network equipment and comprises a second detection identifier; and when the first detection identifier is matched with the second detection identifier, determining that the communication path between the gateway equipment and the edge router is in a normal state. The path detection method and the path detection device provided by the embodiment of the invention can realize effective detection of the communication path between the edge router and the gateway equipment.
Description
Technical Field
The present invention relates to the field of network technologies, and in particular, to a method and an apparatus for detecting a path.
Background
A firewall refers to a protective barrier constructed by a combination of software and hardware devices at the interface between an intranet and an extranet, and between a private network and a public network. Thereby protecting the intranet from the intrusion of an illegal user.
In the current networking configuration, a network fault occurs in any one of two links from the gateway device to the firewall and from the firewall to the edge router, which can cause interruption of service data transmission, so that the detection process of whether a communication path between the gateway device and the edge router is normal is crucial.
Disclosure of Invention
In view of this, the present invention provides a method and an apparatus for detecting a path, which can implement effective detection of a communication path between an edge router and a gateway device.
In a first aspect, an embodiment of the present invention provides a path detection method applied to a software defined network SDN controller, including:
sending a first message for detecting a communication path between the gateway device and an edge router to a gateway device, where the first message includes a first path detection message with a first detection identifier, the gateway device is connected to the edge router through a next hop network device, and the first path detection message is used to enable the gateway device to forward the first path detection message subjected to NAT conversion by the next hop network device to the edge router through the next hop network device;
receiving a second path detection message sent by the gateway device within a preset time period, wherein the second path detection message is a message forwarded to the gateway device by the edge router via the next hop network device and comprises a second detection identifier;
and when the first detection identifier is matched with the second detection identifier, determining that a communication path between the gateway equipment and the edge router is in a normal state.
With reference to the first aspect, in a first possible implementation manner, the first detection identifier and the second detection identifier each include a source IP address and a destination IP address;
when the first detection identifier is matched with the second detection identifier, determining that a communication path between the gateway device and the edge router is in a normal state includes:
and when the source IP address of the first detection identifier is matched with the source IP address of the second detection identifier and the destination IP address of the first detection identifier is matched with the destination IP address of the second detection identifier, determining that the communication path between the gateway equipment and the edge router is in a normal state.
With reference to the first aspect, in a second possible implementation manner, the first packet further includes a forwarding list, where the forwarding list includes first port information for the gateway device to forward the first path detection packet, and the first port information is used to enable the gateway device to send the first path detection packet to the next hop network device through a first port corresponding to the first port information in a multicast manner.
With reference to the first aspect, in a third possible implementation manner, the second path detection packet includes second port information, and the method further includes:
determining the next hop network equipment for forwarding the second path detection message according to the second port information;
and determining a communication path used by the gateway equipment for sending the data message to the edge router according to the next hop network equipment.
With reference to the third possible implementation manner of the first aspect, in a fourth possible implementation manner, the method further includes:
receiving session information transmitted by the next hop network device and forwarded by the gateway device; the session information is used for representing a session established when the network equipment in the extranet and the network equipment in the intranet perform communication interaction;
and when the communication path between the gateway equipment and the edge router is updated, sending the current session information to the next hop network equipment after the path is updated through the gateway equipment.
In a second aspect, an embodiment of the present invention provides a method for detecting a path, which is applied to a network device, and includes:
receiving a first path detection message sent by gateway equipment, wherein the first path detection message comprises a first detection identifier;
sending the first path detection message to an edge router;
receiving a second path detection message sent by the edge router, wherein the second path detection message comprises a second detection identifier;
and sending the second path detection message to a Software Defined Network (SDN) controller through gateway equipment, so that the SDN controller determines that a communication path between the gateway equipment and the edge router is in a normal state when the first detection identifier is matched with the second detection identifier.
With reference to the second aspect, in a first possible implementation manner, the sending the first path detection packet to an edge router includes:
and sending the first path detection message which completes the NAT conversion to the edge router.
With reference to the first possible implementation manner of the second aspect, in a second possible implementation manner, the sending the second path detection packet to a software defined network SDN controller through a gateway device includes:
and sending the second path detection message after the NAT conversion is completed to the SDN controller through the gateway equipment.
With reference to the second aspect, in a third possible implementation manner, the method further includes:
sending, by a gateway device, session information to the SDN controller; the session information is used for representing a session established when the network equipment in the extranet and the network equipment in the intranet perform communication interaction.
In a third aspect, an embodiment of the present invention provides a path detection apparatus, which is applied to a software defined network SDN controller, and includes:
a first sending module, configured to send a first packet for detecting a communication path between a gateway device and an edge router to the gateway device, where the first packet includes a first path detection packet with a first detection identifier, the gateway device is connected to the edge router through a next hop network device, and the first path detection packet is used to enable the gateway device to forward, to the edge router through the next hop network device, the first path detection packet after NAT conversion by the next hop network device;
a first receiving module, configured to receive a second path detection packet sent by the gateway device within a preset time period, where the second path detection packet is a packet forwarded by the edge router to the gateway device via the next-hop network device, and the second path detection packet includes a second detection identifier;
a first determining module, configured to determine that a communication path between the gateway device and the edge router is in a normal state when the first detection identifier matches the second detection identifier.
With reference to the third aspect, in a first possible implementation manner, the first detection identifier and the second detection identifier each include a source IP address and a destination IP address;
the first determining module includes:
and the determining submodule is used for determining that a communication path between the gateway equipment and the edge router is in a normal state when the source IP address of the first detection identifier is matched with the source IP address of the second detection identifier and the destination IP address of the first detection identifier is matched with the destination IP address of the second detection identifier.
With reference to the third aspect, in a second possible implementation manner, the first packet further includes a forwarding list, where the forwarding list includes first port information for the gateway device to forward the first path detection packet, and the first port information is used to enable the gateway device to send the first path detection packet to the next hop network device through a first port corresponding to the first port information in a multicast manner.
With reference to the third aspect, in a third possible implementation manner, the second path detection packet includes second port information, and the apparatus further includes:
a second determining module, configured to determine, according to the second port information, the next hop network device that forwards the second path detection packet;
and a third determining module, configured to determine, according to the next hop network device, a communication path used by the gateway device to send the data packet to the edge router.
In a fourth aspect, an embodiment of the present invention provides a path detection apparatus, applied to a network device, including:
a first receiving module, configured to receive a first path detection packet sent by a gateway device, where the first path detection packet includes a first detection identifier;
a first sending module, configured to send the first path detection packet to an edge router;
a second receiving module, configured to receive a second path detection packet sent by the edge router, where the second path detection packet includes a second detection identifier;
a second sending module, configured to send the second path detection packet to a software defined network SDN controller through a gateway device, so that the SDN controller determines that a communication path between the gateway device and the edge router is in a normal state when the first detection identifier matches the second detection identifier.
With reference to the fourth aspect, in a first possible implementation manner, the first sending module includes:
and the first sending submodule is used for sending the first path detection message which completes the NAT conversion to the edge router.
With reference to the first possible implementation manner of the fourth aspect, in a second possible implementation manner, the second sending module includes:
and the second sending submodule is used for sending the second path detection message which completes the NAT conversion to the SDN controller through the gateway equipment.
According to another aspect of the present invention, there is provided a path detecting apparatus including: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to perform the above method.
According to another aspect of the present invention, there is provided a non-transitory computer readable storage medium having computer program instructions stored thereon, wherein the computer program instructions, when executed by a processor, implement the above-described method.
Therefore, by applying the method and the device for detecting a path provided by the embodiment of the present invention, a Software Defined Network (SDN) controller sends a first packet for detecting a path between a gateway device and an edge router to the gateway device, and the gateway device sends a first path detection packet with a first detection identifier, which is carried in the first packet, to the edge router via a next hop Network device. In a preset time period, the SDN controller receives a second path detection packet sent by the gateway device from the edge router, and when a second detection identifier carried in the second path detection packet is consistent with the first detection identifier, the SDN controller determines that the second path detection packet is a packet returned by the edge router according to the received first path detection packet, that is, the first path detection packet is transmitted to the edge router through a communication path between the gateway device and the edge router, and then returns to the gateway device through an original path between the edge router and the gateway device, so that the SDN controller can determine that the communication path between the gateway device and the edge router is in a normal state. Therefore, the transmission process of the first path detection message on the communication path between the edge router and the gateway device is the same as the transmission process of the normal service message, and the effective detection of the communication path between the edge router and the gateway device can be realized.
Other features and aspects of the present invention will become apparent from the following detailed description of exemplary embodiments, which proceeds with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments, features, and aspects of the invention and, together with the description, serve to explain the principles of the invention.
FIG. 1 shows a flow diagram of a method of path detection according to an embodiment of the invention;
FIG. 2 shows a flow diagram of a method of path detection according to an embodiment of the invention;
FIG. 3 illustrates an exemplary network architecture of the present invention;
FIG. 4 shows a flow diagram of a method of path detection according to an embodiment of the invention;
FIG. 5 shows a flow diagram of a method of path detection according to an embodiment of the invention;
FIG. 6 is a block diagram of a path detection apparatus according to an embodiment of the present invention;
FIG. 7 is a block diagram of a path detection apparatus according to an embodiment of the present invention;
FIG. 8 is a block diagram of a path detection apparatus according to an embodiment of the present invention;
fig. 9 is a block diagram showing a structure of a path detecting apparatus according to an embodiment of the present invention;
fig. 10 is a block diagram illustrating a hardware configuration of a path detection apparatus according to an exemplary embodiment.
Detailed Description
Various exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers can indicate functionally identical or similar elements. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.
Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a better understanding of the present invention. It will be understood by those skilled in the art that the present invention may be practiced without some of these specific details. In some instances, methods, procedures, components, and circuits that are well known to those skilled in the art have not been described in detail so as not to obscure the present invention.
In order to detect a state of a communication path between a gateway device and an edge server, in an embodiment of the present invention, an SDN controller sends, through the gateway device, a first path detection packet with a first detection identifier to an edge router, and receives, through the edge router, a second path detection packet with a second detection identifier. When the first detection identifier is consistent with the second detection identifier, the second path detection identifier is determined to be a detection message returned by the edge router to the gateway device according to the received first path detection identifier, so that the communication path between the gateway device and the edge router can be determined to be normal, and the effective detection of the communication path between the gateway device and the edge router is realized.
Fig. 1 shows a flowchart of a path detection method according to an embodiment of the present invention, which may be applied to an SDN controller. As shown in fig. 1, the path detection method may include the following steps.
The method comprises the steps that an SDN controller sends a first message to a gateway device accessed to the SDN controller, wherein the first message is used for detecting whether a communication path between the gateway device and an edge router is in a normal state. The first message comprises a first path detection message, the first path detection message is provided with a first detection identifier, and the first detection identifier can uniquely identify the first path detection message.
For example, the SDN controller constructs a packet-out packet (a first packet) according to an openflow protocol, where the packet-out packet includes a first path detection packet, and a first detection identifier corresponding to the first path detection packet is a source IP address and a destination IP address of the first path detection packet. And the SDN controller sends the packet-out message constructed by the method to the gateway equipment.
The preset time period is a time period determined by a person skilled in the art according to the detection requirement. In the preset time period, if the SDN controller receives a first path detection packet sent by the gateway device, the SDN controller may determine that a communication path between the gateway device and the edge router is in a normal state, otherwise, the SDN controller determines that the communication path between the gateway device and the edge router is in an abnormal state.
The SDN controller receives a second path detection packet sent by the gateway device, where the second path detection packet is a packet sent by the edge network device to the SDN controller, and has a second detection identifier, where the identifier of the second path detection packet is, for example, an Internet Protocol (IP) address and a destination IP address interconnected between source networks of the second path detection packet.
And the edge router sends the second path detection message to the next hop network equipment of the gateway equipment. And after receiving the second path detection message, the next hop network equipment of the gateway equipment forwards the second path detection message to the gateway equipment. And after receiving the second path detection message, the gateway equipment sends the second path detection message to the SDN controller.
When the first detection identifier matches the second detection identifier, the SDN controller may determine that the second path detection packet is a packet returned by the edge router according to the received first path detection packet, that is, after the first path detection packet is transmitted to the edge router through a communication path between the gateway device and the edge router, the first path detection packet is returned to the gateway device through an original path between the edge router and the gateway device, so that the SDN controller may determine that the communication path between the gateway device and the edge router is in a normal state.
Therefore, by applying the path detection method provided by the embodiment of the present invention, the SDN controller sends the first packet for detecting the path between the gateway device and the edge router to the gateway device, and the gateway device sends the first path detection packet with the first detection identifier, which is carried in the first packet, to the edge router via the next hop network device. In a preset time period, the SDN controller receives a second path detection packet sent by the gateway device from the edge router, and when a second detection identifier carried in the second path detection packet is consistent with the first detection identifier, the SDN controller determines that the second path detection packet is a packet returned by the edge router according to the received first path detection packet, that is, the first path detection packet is transmitted to the edge router through a communication path between the gateway device and the edge router, and then returns to the gateway device through an original path between the edge router and the gateway device, so that the SDN controller can determine that the communication path between the gateway device and the edge router is in a normal state. Therefore, the transmission process of the first path detection message on the communication path between the edge router and the gateway device is the same as the transmission process of the normal service message, and the effective detection of the communication path between the edge router and the gateway device can be realized.
In another embodiment, the first detection identifier and the second detection identifier each include a source IP address and a destination IP address, and when the source IP address of the first detection identifier matches the source IP address of the second detection identifier and the destination IP address of the first detection identifier matches the destination IP address of the second detection identifier, it is determined that the communication path between the gateway device and the edge router is in a normal state.
The first detection identifier is a source IP address and a destination IP address of the first path detection message, the second detection identifier is a source IP address and a destination IP address of the second path detection message, when the source IP address in the first detection identifier matches the source IP address in the second detection identifier and the destination IP address in the first detection identifier matches the destination IP address in the second detection identifier, the SDN controller may determine that the second path detection packet is a packet returned by the edge router according to the received first path detection packet, that is, the second path detection packet is sent to the edge router through a communication path between the gateway device and the edge router, and is also sent to the first path detection packet of the gateway device through a communication path between the gateway device and the edge router, so that the SDN controller can determine that the communication path between the gateway device and the edge router is in a normal state.
In another embodiment, the first packet further includes a forwarding list, where the forwarding list includes first port information for the gateway device to forward the first path detection packet, and the first port information is used to enable the gateway device to send the first path detection packet to the next-hop network device through a first port corresponding to the first port information in a multicast manner.
The SDN controller sends a first message to a gateway device, wherein the first message comprises a first path detection message with a first detection identifier and a forwarding list, and the forwarding list comprises first port information. After receiving the first message, the gateway device obtains the first path detection message and a forwarding list from the first message, obtains first port information from the forwarding list, and forwards the first path detection message to at least one next-hop network device of the gateway device through a first port corresponding to the first port information in a multicast mode, so as to detect the state of a communication path between the gateway device and at least one edge router.
In another embodiment, the second path detection packet includes second port information, where the second port information can represent a next hop network device that forwards the second path detection packet to the gateway device, and the SDN controller determines, according to the second port information, the next hop network device that forwards the second path detection packet to the gateway device, and determines, according to the next hop network device, a communication path for transmitting the data packet between the internal network and the external network. The following describes the path detection method according to the embodiment of the present invention in detail by using a flowchart of the path detection method shown in fig. 2.
Specifically, the detection method of the path shown in fig. 2 includes the following steps.
It should be noted that, in the embodiment of the present invention, steps 201 to 203 are similar to steps 101 to 103, and are not described again here.
Specifically, the second port information is port information added to the second path detection message according to the second port receiving the second path detection message after the gateway device receives the second path detection message, the gateway device has at least one next hop network device, and the second port information can represent the next hop network device forwarding the second path detection message to the gateway device. And the SDN controller acquires second port information in the second path detection message and determines next hop network equipment for forwarding the second path detection message to the gateway equipment according to the second port information.
The gateway device has at least one next hop network device, wherein a plurality of next hop network devices may correspond to the same edge router, or a plurality of next hop network devices respectively correspond to different edge routers, that is, there are a plurality of communication paths that can be used for the gateway device to perform data packet transmission with the edge routers, and the communication path actually used for transmitting the data packet is one of the communication paths.
For example, the gateway device has two next-hop network devices, network device 1 and network device 2, and the edge router includes: the router 1 and the router 2, the network device 1 is connected to the router 1, and the network device 2 is connected to the router 2, that is, the communication path between the gateway device and the edge router includes: a communication path 1 (gateway device-network device 1-router 1) and a communication path 2 (gateway device-network device 2-router 2), wherein the communication path 1 is a primary path and the communication path 2 is a backup path. When the main path is in a normal state, the SDN controller determines that the communication path 1 is a communication path used by the gateway device for transmitting the data message to the edge router, and when the main path is in an abnormal state, the SDN controller determines that the communication path 2 is a communication path used by the gateway device for transmitting the data message to the edge router.
In a preset time, if a next hop network device represented by second port information carried in a second path detection message received by the SDN controller is a network device 1, the SDN controller determines that the communication path 1 is in a normal state, and further determines that the gateway device sends a data message to the edge router through the communication path 1 (even if the SDN controller receives the second path detection message sent by the network device 2 in the preset time, the communication path through which the gateway device sends the data message to the edge router is still determined to be the communication path 1);
or, within a preset time, if the next hop network device represented by the second port information carried in the second path detection message received by the SDN controller is the network device 2 and the second path detection message sent by the network device 1 is not received within the preset time, the SDN controller determines that the communication path 1 is in an abnormal state, and further determines that the gateway device sends the data message to the edge router through the communication path 2.
In order to make the above embodiments of the present invention better understood by those skilled in the art, the embodiments of the present invention are explained below by way of an example shown in fig. 3.
In particular, fig. 3 shows an exemplary network architecture diagram of the present invention. Wherein, GW is gateway equipment, GW has floating IP: IP address 1, and gateway IP: IP address 2. FW1 is network device 1, FW2 is network device 2, R1 is edge router 1, and R2 is edge router 2.
Referring to fig. 3, the SDN controller constructs a packet-out packet (first packet) according to an openflow protocol, where the packet-out packet includes a first path detection packet and a forwarding list, and a source IP address of the first path detection packet is a floating IP of the gateway device: IP address 1, destination IP address is gateway IP: the IP address 2, i.e. the first detection identifier of the first path detection packet, is: source IP address: IP address 1, destination IP address: IP address 2. The forwarding list comprises first port information for forwarding the first path detection message to FW1 and FW2, and the SDN controller sends the packet-out message to the GW.
After receiving the packet-out message, the GW obtains a first path detection message and a forwarding list from the packet-out message, where a first detection identifier of the first path detection message is: source IP address: IP address 1, destination IP address: IP address 2. Further, the GW sends the first path detection message to FW1 and FW2 by using a multicast mode through the first port corresponding to the first port information in the forwarding list.
After receiving the first path detection message, FW1(FW2) performs routing policy matching according to the source IP address and the destination IP address of the first path detection message, determines that the next hop network device is R1(R2), performs NAT conversion on the first path detection message, and sends the first path detection message after NAT conversion to R1(R2), where a first detection identifier of the first path detection message is: source IP address: IP address 2, destination IP address: IP address 1.
And after receiving the first path detection message which is forwarded by the FW1(FW2) and subjected to NAT conversion, R1(R2) forwards the first path detection message according to the source IP address and the destination IP address of the received first path detection message. Since the first path detection message is the first path detection message subjected to the NAT conversion, after the routing policy matching is performed on the R1(R2) according to the first path detection message, the first path detection message is forwarded back to the FW1(FW2) as the second path detection message.
The FW1(FW2) receives the second path detection packet, performs routing policy matching according to the source IP address and the destination IP address of the second path detection packet, determines that the next hop network device of the second path detection packet is GW, and after performing NAT conversion on the second path detection packet, the FW1(FW2) forwards the second path detection packet subjected to NAT conversion to the GW, where a second detection identifier of the second path detection packet is: source IP address: IP address 1, destination IP address: IP address 2.
After receiving the second path detection packet, the GW determines to receive second port information of the second path detection packet, and after adding the second port information to the second path detection packet, forwards the second path detection packet to the SDN controller, for example, the GW may construct a packet-in packet carrying the second path detection packet, and send the packet-in packet to the SDN controller, and the SDN controller may obtain the second path detection packet from the packet-in packet.
And the SDN controller receives a second path detection message sent by the GW, and determines that the second path detection message is a message returned by the edge router after receiving the first path detection message because a second detection identifier carried in the second path detection message is matched with a first detection identifier carried in the first path detection message, so that the communication path between the GW and the edge router can be determined to be in a normal state. Further, the SDN controller determines, according to second port information carried in the second path detection message, that the network device returning the second path detection message is FW1 or FW 2.
In a preset time period, if the GW receives only the second path detection message forwarded by FW1, or receives both the second path detection message forwarded by FW1 and the second path detection message forwarded by FW2, the SDN controller determines that a communication path for the GW to transmit the data message to the edge router is: GW-FW 1-R1; if the GW receives only the second path detection packet forwarded by FW2, the SDN controller determines that a communication path used for the GW to transmit the data packet to the edge router is: GW-FW 2-R2.
Therefore, the SDN controller can determine the communication path for forwarding the data message according to the detection result of the communication path from the gateway device to the edge router, so that when the communication path for transmitting the data message is abnormal, the gateway device can switch the data message to another communication path in time for transmission, and the stability of transmitting the data message can be ensured.
In another embodiment, the next hop network device of the gateway device reports, to the SDN controller, information of a session established for a data packet transmitted between the internal network and the external network, so that when a communication path for transmitting the data packet between the gateway device and the edge router is updated, the SDN controller may send, to the next hop network device on the updated communication path, session information of the next hop network device on the communication path before the update. The following describes the path detection method according to the embodiment of the present invention in detail by using a flowchart of the path detection method shown in fig. 4.
Specifically, the detection method of the path shown in fig. 4 includes the following steps.
It should be noted that steps 401 to 405 in the embodiment of the present invention are similar to steps 201 to 205 in the embodiment described above.
When receiving a data message of a network device in an external network accessing a network device in an internal network, a next hop network device of the gateway device may establish a session according to the data message, where the session is specifically embodied as establishment of connection between the internal network and the external network, and may represent a connection state between the internal network and the external network for the data message. The session information corresponding to the session includes IP address information for forwarding data packets, and includes: protocol, source IP address, source port, destination IP address, and destination port. After a session between the intranet and the extranet is established on the next hop network device based on one data message, the next hop network device forwards the subsequent data message of the data message by matching the session information, and operations such as detection and filtration of the data message matching the session information are not needed, so that the forwarding efficiency of the data message can be improved.
When a next hop network device of the gateway device establishes a session or deletes the session, corresponding session information is reported to the SDN controller through the gateway device, and the session information received by the SDN controller updates the session information on the next hop network device of the gateway device in real time.
When the SDN controller updates the communication path between the gateway device and the edge router according to the second path detection packet, the session information may be sent to the next-hop network device on the updated communication path through the gateway device.
For example, referring to fig. 2, when an SDN controller updates a communication path between a gateway device and the edge router from GW-FW1-R1 to GW-FW2-R2, the SDN controller sends session information established on the FW1 to the FW2 through the GW; or,
when the communication path between the gateway device and the edge router is updated to GW-FW1-R1 from GW-FW2-R2 by the SDN controller, the SDN controller sends the session information established on the FW2 to the FW1 through the GW.
In this way, after the SDN controller updates the communication path between the gateway device and the edge router, the session information established on the next hop network device 1 on the communication path before updating is sent to the next hop network device 2 on the communication path after updating, so that the next hop network device 2 can directly forward the data packet in which the session information is established on the next hop network device 1, and the forwarding efficiency of the data packet can be improved.
Fig. 5 is a flowchart illustrating a path detection method according to an embodiment of the present invention, which may be applied to a network device. As shown in fig. 5, the path detection method may include the following steps.
specifically, the first path detection packet is a packet sent by the SDN controller to the gateway device and used for detecting a state of a communication path between the gateway device and the edge router, and has a first detection identifier, where the first detection identifier is capable of uniquely identifying the first path detection packet, and for example, the first detection identifier includes a source IP address and a destination IP address of the first path detection packet. And after receiving the first path detection message, the gateway equipment sends the first path detection message to the network equipment.
For example, the SDN controller may construct a first packet carrying the first path detection packet and the forwarding list, and send the first packet to the gateway device. The gateway device obtains a first path detection message and a forwarding list from the first message, wherein the forwarding list includes first port information for the gateway device to forward the first path detection message to the next hop network device. And the gateway equipment sends the first path detection message to network equipment (next hop network equipment of the gateway equipment) according to the first port represented by the first port information.
after receiving the first path detection message, the network device performs routing policy matching according to the source IP address and the destination IP address of the first path detection message, determines that the next hop network device is an edge router, and can send the first path detection message to the edge router.
In a possible implementation manner, the step 502 of sending the first path detection packet to an edge router includes:
and sending the first path detection message which completes the NAT conversion to the edge router.
The network equipment performs NAT conversion on the first path detection message, converts a source IP address of the first path detection message into a destination IP address, converts the destination IP address into the source IP address, and sends the first path detection message subjected to the NAT conversion to the edge router, so that the edge router can send the first path detection message back to the network equipment after routing strategy matching.
For example, before performing NAT conversion, the source IP address of the first path detection packet is: IP address 1, destination IP address is: IP address 2, at this time, the first detection identifier of the first path detection packet is: source IP address: IP address 1, destination IP address: IP address 2. After performing NAT conversion, the source IP address of the first path detection packet is: IP address 2, destination IP address is: IP address 1, the first detection identifier of the first path detection packet at this time is: source IP address: IP address 2, destination IP address: IP address 1.
and the edge router performs routing strategy matching according to the first path detection message, determines that the next hop network equipment is the network equipment, and sends the first path detection message as a second path detection message to the network equipment. The second path detection message comprises a second detection identifier, and the second detection identifier is a source IP address and a destination IP address of the second path detection message.
And the network equipment sends the second path detection message to the gateway equipment, and after receiving the second path detection message, the gateway equipment forwards the second path detection message to the SDN controller, so that the SDN controller can match a second detection identifier carried by the second path detection message with the first detection identifier, and according to a matching result, determines whether the second path detection message is a detection message returned by the edge router according to the first path detection message, so as to determine the state of a communication link between the gateway equipment and the edge router. And when the first detection identifier is matched with the second detection identifier, determining that the communication path between the gateway equipment and the edge router is in a normal state.
In a possible implementation manner, the sending the second path detection packet to the SDN controller through the gateway device includes:
and sending the second path detection message after the NAT conversion is completed to the SDN controller through the gateway equipment.
And the network equipment performs NAT conversion on the second path detection message, converts a source IP address of the second path detection message into a destination IP address, converts the destination IP address into the source IP address, and transmits the second path detection message subjected to the NAT conversion to the gateway equipment.
For example, before performing NAT translation, the source IP address of the second path detection packet is: IP address 2, destination IP address is: the IP address 1, at this time, the second detection identifier of the second path detection packet is: source IP address: IP address 2, destination IP address: IP address 1. After performing the NAT conversion, the source IP address of the second path detection packet is: IP address 1, destination IP address is: and 2, the second detection identifier of the second path detection message is: source IP address: IP address 1, destination IP address: IP address 2.
After receiving the second path detection message, the gateway device forwards the second path detection message to the SDN controller, where a second detection identifier (source IP address: IP address 1, destination IP address: IP address 2) of the second path detection message matches a first detection identifier (source IP address: IP address 1, destination IP address: IP address 2) of the first path detection message, so that the SDN controller may determine that the second path detection message is a detection message returned by the edge router according to the first path detection message, and thus the SDN controller determines that a communication path between the gateway device and the edge router is normal.
For example, after receiving the second path detection packet, the gateway device may add second port information to the second path detection packet according to a receiving port of the second path detection packet, so that after receiving the second path detection packet, the SDN controller may determine, according to the second port information, a network device that forwards the second path detection packet, and further determine that a communication path between the gateway device and the edge router, which includes the network device, is normal.
In one possible implementation, the method may further include the following steps.
Sending, by a gateway device, session information to the SDN controller; the session information is used for representing a session established when the network equipment in the extranet and the network equipment in the intranet perform communication interaction.
When receiving a data message of a network device in an external network accessing a network device in an internal network, the network device may establish a session according to the data message, and the session is embodied as establishment of connection between the internal network and the external network, that is, a connection state between the internal network and the external network may be represented. The session information corresponding to the session includes IP address information for forwarding data packets, and includes: protocol, source IP address, source port, destination IP address, and destination port. After a session between the intranet and the extranet is established on the network equipment based on one data message, the network equipment forwards the subsequent data message of the data message by matching the session information, and the operations such as detection, filtration and the like are not carried out on the data message which can be matched with the session information any more, so that the forwarding efficiency of the data message can be improved.
When the network device establishes a session or deletes the session, the session information is reported to the SDN controller through the gateway device, the session information on the network device is updated in real time by the session information received by the SDN controller, so that when a communication path used for transmitting data messages between the gateway device and the edge router is updated, the session information of the network device on the communication path before updating is sent to the network device on the updated communication path through the gateway device, and the forwarding efficiency of the data messages is improved.
Fig. 6 shows a block diagram of a path detection apparatus according to an embodiment of the present invention, which is applied to a software defined network SDN controller, and includes:
a first sending module 601, configured to send, to a gateway device, a first packet for detecting a communication path between the gateway device and an edge router, where the first packet includes a first path detection packet with a first detection identifier, the gateway device is connected to the edge router through a next hop network device, and the first path detection packet is used to enable the gateway device to forward, to the edge router through the next hop network device, the first path detection packet after NAT conversion by the next hop network device;
a first receiving module 602, configured to receive a second path detection packet sent by the gateway device within a preset time period, where the second path detection packet is a packet that is forwarded by the edge router to the gateway device via the next-hop network device, and the second path detection packet includes a second detection identifier;
the first determining module 603 may be configured to determine that a communication path between the gateway device and the edge router is in a normal state when the first detection identifier matches the second detection identifier.
Fig. 7 is a block diagram illustrating a structure of a path detection apparatus according to an embodiment of the present invention, where a first sending module 701, a first receiving module 702, and a first determining module 703 are similar to the first sending module 601, the first receiving module 602, and the first determining module 603 in the foregoing embodiments, and no further description is given here in the embodiment of the present invention.
In a possible implementation manner, referring to fig. 7, the first detection identifier and the second detection identifier each include a source IP address and a destination IP address; the first determining module 703 may include:
the determining sub-module 7031 may be configured to determine that a communication path between the gateway device and the edge router is in a normal state when the source IP address of the first detection identifier matches the source IP address of the second detection identifier and the destination IP address of the first detection identifier matches the destination IP address of the second detection identifier.
In a possible implementation manner, referring to fig. 7, the first packet further includes a forwarding list, where the forwarding list includes first port information for the gateway device to forward the first path detection packet, and the first port information is used to enable the gateway device to send the first path detection packet to the next hop network device through a first port corresponding to the first port information in a multicast manner.
In a possible implementation manner, referring to fig. 7, the second path detection packet includes second port information, and the apparatus further includes:
a second determining module 704, configured to determine, according to the second port information, the next hop network device that forwards the second path detection packet;
the third determining module 705 may be configured to determine, according to the next hop network device, a communication path used by the gateway device to send the data packet to the edge router.
In one possible implementation, referring to fig. 7, the apparatus further includes:
a second receiving module 706, configured to receive session information sent by the next hop network device and forwarded by the gateway device; the session information is used for representing a session established when the network equipment in the extranet and the network equipment in the intranet perform communication interaction;
the second sending module 707 may be configured to, when the communication path between the gateway device and the edge router is updated, send the current session information to the next hop network device after the path is updated through the gateway device.
Fig. 8 is a block diagram of a path detection apparatus according to an embodiment of the present invention, applied to a network device, including:
a first receiving module 801, configured to receive a first path detection packet sent by a gateway device, where the first path detection packet includes a first detection identifier;
a first sending module 802, configured to send the first path detection packet to an edge router;
a second receiving module 803, configured to receive a second path detection packet sent by the edge router, where the second path detection packet includes a second detection identifier;
a second sending module 804, configured to send the second path detection packet to a software defined network SDN controller through a gateway device, so that the SDN controller determines that a communication path between the gateway device and the edge router is in a normal state when the first detection identifier matches the second detection identifier.
Fig. 9 is a block diagram illustrating a structure of a path detection apparatus according to an embodiment of the present invention, where a first receiving module 901, a first sending module 902, a second receiving module 903, and a second sending module 904 are similar to the first receiving module 801, the first sending module 802, the second receiving module 803, and the second sending module 804, and no further description is given here in the embodiment of the present invention.
In one possible implementation manner, referring to fig. 9, the first sending module 902 includes:
the first sending sub-module 9021 may be configured to send the first path detection packet that completes the NAT conversion to the edge router.
In a possible implementation manner, referring to fig. 9, the second sending module 904 includes:
the second sending submodule 9041 may be configured to send the second path detection packet that completes the NAT conversion to the SDN controller through the gateway device.
In one possible implementation, referring to fig. 9, the apparatus further includes:
a fifth sending module 905, configured to send session information to the SDN controller through a gateway device; the session information is used for representing a session established when the network equipment in the extranet and the network equipment in the intranet perform communication interaction.
Fig. 10 is a block diagram illustrating a hardware configuration of a path detection apparatus according to an exemplary embodiment. In practical applications, the device may be implemented by a server. Referring to fig. 10, the apparatus 1300 may include a processor 1301, a machine-readable storage medium 1302 storing machine-executable instructions. The processor 1301 and the machine-readable storage medium 1302 may communicate via a system bus 1303. Also, the processor 1301 performs the path detection method described above by reading machine-executable instructions in the machine-readable storage medium 1302 corresponding to the path detection logic.
The machine-readable storage medium 1302 referred to herein may be any electronic, magnetic, optical, or other physical storage device that can contain or store information such as executable instructions, data, and the like. For example, the machine-readable storage medium may be: random Access Memory (RAM), volatile Memory, non-volatile Memory, flash Memory, a storage drive (e.g., a hard drive), a solid state drive, any type of storage disk (e.g., an optical disk, dvd, etc.), or similar storage media, or a combination thereof.
Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terms used herein were chosen in order to best explain the principles of the embodiments, the practical application, or technical improvements to the techniques in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.
Claims (16)
1. A path detection method is applied to a Software Defined Network (SDN) controller and comprises the following steps:
sending a first message for detecting a communication path between gateway equipment and an edge router to the gateway equipment, wherein the first message comprises a first path detection message with a first detection identifier, the gateway equipment is connected with the edge router through next hop network equipment, and the first path detection message is forwarded to the edge router by the gateway equipment through the next hop network equipment and is subjected to NAT conversion by the next hop network equipment;
receiving a second path detection message sent by the gateway device within a preset time period, wherein the second path detection message is a message forwarded to the gateway device by the edge router via the next hop network device and comprises a second detection identifier;
and when the first detection identifier is matched with the second detection identifier, determining that a communication path between the gateway equipment and the edge router is in a normal state.
2. The method of claim 1, wherein the first detection flag and the second detection flag each include a source IP address and a destination IP address;
when the first detection identifier is matched with the second detection identifier, determining that a communication path between the gateway device and the edge router is in a normal state includes:
and when the source IP address of the first detection identifier is matched with the source IP address of the second detection identifier and the destination IP address of the first detection identifier is matched with the destination IP address of the second detection identifier, determining that the communication path between the gateway equipment and the edge router is in a normal state.
3. The method according to claim 1, wherein the first packet further includes a forwarding list, the forwarding list includes first port information for the gateway device to forward the first path detection packet, and the first port information is used to enable the gateway device to send the first path detection packet to the next-hop network device through a first port corresponding to the first port information in a multicast manner.
4. The method of claim 1, wherein the second path detection packet includes second port information, the method further comprising:
determining the next hop network equipment for forwarding the second path detection message according to the second port information;
and determining a communication path used by the gateway equipment for sending the data message to the edge router according to the next hop network equipment.
5. The method of claim 4, further comprising:
receiving session information transmitted by the next hop network device and forwarded by the gateway device; the session information is used for representing a session established when the network equipment in the extranet and the network equipment in the intranet perform communication interaction;
and when the communication path between the gateway equipment and the edge router is updated, sending the current session information to the next hop network equipment after the path is updated through the gateway equipment.
6. A method for detecting a path is applied to a network device, and comprises the following steps:
receiving a first path detection message sent by gateway equipment, wherein the first path detection message comprises a first detection identifier;
sending the first path detection message to an edge router;
receiving a second path detection message sent by the edge router, wherein the second path detection message comprises a second detection identifier;
and sending the second path detection message to a Software Defined Network (SDN) controller through gateway equipment, so that the SDN controller determines that a communication path between the gateway equipment and the edge router is in a normal state when the first detection identifier is matched with the second detection identifier.
7. The method according to claim 6, wherein said sending the first path detection packet to an edge router comprises:
and sending the first path detection message which completes the NAT conversion to the edge router.
8. The method according to claim 7, wherein sending the second path detection packet to a Software Defined Network (SDN) controller through a gateway device comprises:
and sending the second path detection message after the NAT conversion is completed to the SDN controller through the gateway equipment.
9. The method of claim 6, further comprising:
sending, by a gateway device, session information to the SDN controller; the session information is used for representing a session established when the network equipment in the extranet and the network equipment in the intranet perform communication interaction.
10. A path detection device applied to a Software Defined Network (SDN) controller comprises:
a first sending module, configured to send a first packet for detecting a communication path between a gateway device and an edge router to the gateway device, where the first packet includes a first path detection packet with a first detection identifier, the gateway device is connected to the edge router through a next hop network device, and the first path detection packet is forwarded to the edge router through the next hop network device by the gateway device and is subjected to NAT conversion by the next hop network device;
a first receiving module, configured to receive a second path detection packet sent by the gateway device within a preset time period, where the second path detection packet is a packet forwarded by the edge router to the gateway device via the next-hop network device, and the second path detection packet includes a second detection identifier;
a first determining module, configured to determine that a communication path between the gateway device and the edge router is in a normal state when the first detection identifier matches the second detection identifier.
11. The apparatus of claim 10, wherein the first and second detection flags each comprise a source IP address and a destination IP address;
the first determining module includes:
and the determining submodule is used for determining that a communication path between the gateway equipment and the edge router is in a normal state when the source IP address of the first detection identifier is matched with the source IP address of the second detection identifier and the destination IP address of the first detection identifier is matched with the destination IP address of the second detection identifier.
12. The apparatus according to claim 10, wherein the first packet further includes a forwarding list, the forwarding list includes first port information for the gateway device to forward the first path detection packet, and the first port information is used to enable the gateway device to send the first path detection packet to the next-hop network device through a first port corresponding to the first port information in a multicast manner.
13. The apparatus of claim 10, wherein the second path detection packet includes second port information, the apparatus further comprising:
a second determining module, configured to determine, according to the second port information, the next hop network device that forwards the second path detection packet;
and a third determining module, configured to determine, according to the next hop network device, a communication path used by the gateway device to send the data packet to the edge router.
14. A path detection device applied to a network device includes:
a first receiving module, configured to receive a first path detection packet sent by a gateway device, where the first path detection packet includes a first detection identifier;
a first sending module, configured to send the first path detection packet to an edge router;
a second receiving module, configured to receive a second path detection packet sent by the edge router, where the second path detection packet includes a second detection identifier;
a second sending module, configured to send the second path detection packet to a software defined network SDN controller through a gateway device, so that the SDN controller determines that a communication path between the gateway device and the edge router is in a normal state when the first detection identifier matches the second detection identifier.
15. The apparatus of claim 14, wherein the first sending module comprises:
and the first sending submodule is used for sending the first path detection message which completes the NAT conversion to the edge router.
16. The apparatus of claim 15, wherein the second sending module comprises:
and the second sending submodule is used for sending the second path detection message which completes the NAT conversion to the SDN controller through the gateway equipment.
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Effective date of registration: 20230625 Address after: 310052 11th Floor, 466 Changhe Road, Binjiang District, Hangzhou City, Zhejiang Province Patentee after: H3C INFORMATION TECHNOLOGY Co.,Ltd. Address before: 310052 Changhe Road, Binjiang District, Hangzhou, Zhejiang Province, No. 466 Patentee before: NEW H3C TECHNOLOGIES Co.,Ltd. |