A network switching device

Abstract

The embodiment of the present invention discloses a network switching device. The network switching device includes: a switching unit and a NAT unit; the switching unit is used to parse the message to be forwarded when receiving the message to be forwarded from the internal network or the external network, and if it is determined according to the parsing result that the message to be forwarded needs to be NAT converted, the message to be forwarded is sent to the NAT unit; the NAT unit is used to generate a NAT result message matching the message to be forwarded according to the local NAT configuration table when receiving the message to be forwarded, and return the NAT result message to the switching unit; the switching unit is also used to forward the NAT result message to the matching external network or internal network according to the local forwarding table when receiving the NAT result message returned by the NAT unit. The technical solution of this embodiment solves the problem of heavy CPU burden in the external switching unit, achieves the effect of reducing the cost of the network switching device and improving the message switching efficiency.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of communication technology, specifically to switching hardware technology, and in particular to a network switching device. Background Art

[0002] When a device that has been assigned a private IP address (a dedicated address used only within the LAN) within a local area network needs to communicate with other devices on the Internet, it needs to convert the local IP address into an IP address that can be recognized by other devices on the Internet. Network Address Translation (NAT) is used to convert private IP addresses into public IP addresses.

[0003] In the prior art, NAT from the intranet to the extranet or from the extranet to the intranet is mainly implemented through a built-in CPU in a switching unit (switch) based on a NAT configuration table.

[0004] However, in the process of implementing the present invention, the inventors found that the prior art has the following technical defects: the processing tasks performed by the built-in CPU in the switching unit are relatively complex, and taking NAT into consideration while performing message forwarding will cause a huge burden on limited CPU resources. In particular, in application scenarios with strong message concurrency, it will cause a certain packet loss rate, affecting the switching performance of the switching unit. Summary of the invention

[0005] The embodiment of the present invention provides a network switching device to achieve maximum savings in the implementation cost of the network switching device while improving the efficiency of message switching and effectively reducing the processing pressure on a CPU in a switching unit.

[0006] The embodiment of the present invention provides a network switching device, including: a switching unit and a network address translation NAT unit; the NAT unit is composed of a CPU and peripheral circuits;

[0007] The switching unit is used to parse the message to be forwarded when receiving the message to be forwarded from the intranet or the extranet, and if it is determined according to the parsing result that the message to be forwarded needs to be NAT converted, the message to be forwarded is sent to the NAT unit;

[0008] The NAT unit is used to generate a NAT result message matching the message to be forwarded according to the local NAT configuration table when receiving the message to be forwarded, and return the NAT result message to the switching unit;

[0009] The switching unit is further configured to forward the NAT result message to a matching external network or internal network according to a local forwarding table when receiving the NAT result message returned by the NAT unit.

[0010] Optionally, the switching unit interacts with the external network to send and receive messages through the first data port, the switching unit interacts with the internal network to send and receive messages through the second data port, and the switching unit interacts with the NAT unit to send and receive messages through the third data port.

[0011] Optionally, the switching unit is also used for:

[0012] receiving a NAT configuration instruction sent by a configuration terminal through a standard configuration interface, and sending NAT configuration information matching the NAT configuration instruction to the NAT unit through a fourth data port;

[0013] The NAT unit is further used to update and store the local NAT configuration table according to the received NAT configuration information.

[0014] Optionally, the switching unit is also used for:

[0015] When receiving NAT configuration information from an intranet or an extranet, the NAT configuration information is stored locally.

[0016] Optionally, the switching unit is also used for:

[0017] Receiving a NAT unit firmware upgrade instruction sent by a configuration terminal through a standard configuration interface, and sending a NAT firmware matching the NAT unit firmware upgrade instruction to the NAT unit through a fifth data port;

[0018] The NAT unit is also used for: when receiving the NAT firmware sent by the switching unit, using the NAT firmware to perform firmware upgrade, and when the firmware upgrade is completed, triggering the NAT unit to restart the system so that the NAT firmware takes effect.

[0019] Optionally, the switching unit is also used for:

[0020] When receiving the NAT firmware from the intranet or the extranet, the NAT firmware is stored locally.

[0021] Optionally, the fourth data port is a UART port supporting a serial communication protocol; or

[0022] The fifth data port is a UART port supporting a serial communication protocol.

[0023] Optionally, a data plane development kit DPDK is pre-installed in the NAT unit, and a vector packet processing VPP code is pre-installed in the DPDK.

[0024] Optionally, the NAT unit is specifically used to:

[0025] When a message to be forwarded is received through DPDK, the message to be forwarded is mapped to the user space;

[0026] Through the VPP code in the user space, a NAT result message matching the message to be forwarded is generated according to the local NAT configuration table;

[0027] The NAT result message is returned to the switching unit through the DPDK.

[0028] Optionally, the exchange unit is also used to:

[0029] After parsing the message to be forwarded, if it is determined according to the parsing result that the message to be forwarded needs to be subjected to message filtering detection, the message to be forwarded is sent to the NAT unit;

[0030] The NAT unit is also used for: upon receiving a message to be forwarded, detecting whether the message to be forwarded satisfies a message filtering condition according to a local message filtering configuration table; if so, directly filtering the message to be forwarded; otherwise, returning the message to be forwarded to the switching unit;

[0031] The switching unit is further used for: when receiving the message to be forwarded returned by the NAT unit, forwarding the message to be forwarded to a matching external network or internal network according to the local forwarding table.

[0032] The technical solution of this embodiment provides a new high-performance, easy-to-use, and cost-effective NAT solution by adapting a NAT unit independent of the switching unit in the network switching device, independently setting a CPU and peripheral circuits in the NAT unit, and independently setting a CPU in the NAT unit to independently implement NAT processing of the message. The technical solution can effectively alleviate the problem of heavy CPU burden in the switching unit, and improve the efficiency of message exchange while saving the implementation cost of the network switching device to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A structural diagram of a network switching device provided in Embodiment 1 of the present invention;

[0034] Figure 2 A schematic diagram of message forwarding based on a NAT configuration table provided in Embodiment 1 of the present invention;

[0035] Figure 3 This is an information interaction diagram in a configuration delivery or firmware upgrade scenario applicable to an embodiment of the present invention;

[0036] Figure 4 The diagram is an information interaction diagram in a NAT conversion scenario of a message applicable to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the embodiments of the present invention, rather than to limit the embodiments of the present invention. It is also necessary to explain that, for ease of description, only parts related to the embodiments of the present invention are shown in the accompanying drawings, rather than all structures.

[0038] It should also be noted that, for ease of description, only the part relevant to the present invention but not all content is shown in the accompanying drawings. It should be mentioned before discussing exemplary embodiments in more detail that some exemplary embodiments are described as processing or methods depicted as flow charts. Although the flow chart describes each operation (or step) as sequential processing, many operations therein can be implemented in parallel, concurrently or simultaneously. In addition, the order of each operation can be rearranged. When its operation is completed, the processing can be terminated, but it can also have additional steps not included in the accompanying drawings. The processing can correspond to methods, functions, procedures, subroutines, subprograms, etc.

[0039] Embodiment 1

[0040] Figure 1 This is a structural diagram of a network switching device provided in Embodiment 1 of the present invention. This embodiment is applicable to the situation where the network switching device forwards and performs NAT on received messages. The network switching device includes: a switching unit 110 and a NAT unit 120.

[0041] The NAT unit 120 is composed of a CPU and peripheral circuits. The CPU, as the core device of the NAT unit 120, mainly performs NAT functions on received messages, while the peripheral circuits are responsible for auxiliary functions such as power supply to the CPU, interface communication with the switching unit 110, or serial-to-parallel conversion.

[0042] The switching unit 110 is used to parse the message to be forwarded when receiving the message to be forwarded from the intranet or the extranet. If it is determined according to the parsing result that the message to be forwarded needs to be NAT converted, the message to be forwarded is sent to the NAT unit.

[0043] like Figure 1As shown, the network switching device serves as an intermediary device connecting each intranet device (intranet device 1, intranet device 2, ..., intranet device n) and the external network. It can send the received intranet data packet to the external network, and can also send the external network data packet received from the external network to the matching intranet device. It can also simply serve as an intranet forwarding node to forward the intranet data packet sent by an intranet device to another intranet device, and simply serve as an external network forwarding node to forward an external network data packet received from the external network to other external network nodes.

[0044] It is understandable that the network switching device needs to perform NAT processing only when sending a received intranet data packet to an extranet or sending an extranet data packet received from an extranet to a matching intranet device. Therefore, when the switching unit 110 receives a message to be forwarded from an intranet or an extranet, it needs to parse the message to be forwarded and determine whether the message to be forwarded needs to be NAT converted based on the parsing result.

[0045] In a specific example, the message to be transmitted generally contains a source IP and a destination IP. The source IP represents the IP address of the device that sends the message, and the destination IP represents the IP address of the device that receives the message. By combining the source IP and the destination IP, the transmission type of the message can be determined. In other words, whether it needs to be transmitted across the intranet or the extranet.

[0046] If the transmission type needs to cross the intranet and the extranet, the switching unit 110 needs to first send the message to the NAT unit for NAT conversion, and then perform corresponding forwarding processing on the message; if the transmission type does not need to cross the intranet and the extranet, for example, the message is only transmitted between different devices in the intranet, then the switching unit does not need to send the message to the NAT unit for NAT conversion, and only needs to directly forward the message between the intranet devices.

[0047] The NAT unit 120 is used to generate a NAT result message matching the message to be forwarded according to the local NAT configuration table when receiving the message to be forwarded, and return the NAT result message to the switching unit.

[0048] Before the switching unit 110 forwards the message between the intranet and the extranet, it needs to send the message to the NAT unit for NAT conversion. Figure 2 A schematic diagram of message forwarding based on a NAT configuration table provided in Embodiment 1 of the present invention is shown.

[0049] like Figure 2As shown, it is assumed that the intranet device 1 sends message 1 to the external network, the source IP of the message 1 is 10.0.0.1, and the destination IP is 192.168.0.100, where 10.0.0.1 is the private IP address of the intranet and cannot be identified by the external network. Therefore, it is necessary to query the NAT configuration table, and generate a NAT result message matching the message 1 to be forwarded according to the local NAT configuration table. The source IP of the NAT result message is 192.168.0.1.0.0.1 obtained by the table query, and the destination IP is still 192.168.0.100. Afterwards, the NAT unit returns the NAT result message to the switching unit.

[0050] The switching unit 110 is further configured to forward the NAT result message to a matching external network or internal network according to a local forwarding table when receiving the NAT result message returned by the NAT unit 120.

[0051] After receiving the NAT result message returned by the NAT unit, the switching unit 110 sends the NAT result message to the external network device with the IP address of 192.168.0.100 through the external network according to the destination IP 192.168.0.100.

[0052] The local forwarding table is used to determine, when receiving a message to be forwarded, from which port of the switching unit 110 to forward the message according to the IP address of the message to be forwarded.

[0053] Those skilled in the art can understand that the switching unit 110 is similar to the message forwarding function of various existing switching devices (typically, switches or routers, etc.), the difference is that the technical solution of the embodiment of the present invention does not use the CPU built into the switching unit 110 to implement NAT processing, but implements the NAT processing function by using the CPU in an independent NAT unit.

[0054] Optionally, the ports used for message sending and receiving interaction can be distinguished in the switching unit 110. The switching unit 110 can send and receive messages with the external network through the first data port, the switching unit 110 can send and receive messages with each internal network device through the second data port, and the switching unit 110 can send and receive messages with the NAT unit through the third data port. Different types of messages can be independently sent and received through different data ports.

[0055] It should be noted that the above description is based on sending messages from the intranet to the extranet as an example, and the network switching device is also applicable to sending messages from the extranet to the intranet. Figure 2As shown, assuming that the device in the external network sends message 2 to the internal network device 3, the source IP of message 2 is 192.168.0.100, and the destination IP is 192.168.0.1.0.0.2. Here, the destination IP 192.168.0.1.0.0.2 is the public IP address exposed by the switching unit. After receiving message 2 from the external network, the switching unit 110 parses message 2 and determines that message 2 needs to be NAT converted, so it sends message 2 to the NAT unit 120.

[0056] After receiving the message 2 to be forwarded, the NAT unit 120 generates a NAT result message matching the message 2 to be forwarded by querying the NAT configuration table. The source IP of the NAT result message is 192.168.0.100, and the destination IP is 10.0.0.3 obtained by querying the NAT configuration table. Then, the NAT unit 120 returns the NAT result message to the switching unit 110. Thereafter, the switching unit 110 sends the NAT result message to the intranet device 3 according to the destination IP in the NAT result message and the local forwarding table.

[0057] Optionally, a flat development kit may be pre-installed in the NAT unit, and the NAT unit may be updated or upgraded.

[0058] The technical solution of this embodiment provides a new high-performance, easy-to-use, and cost-effective NAT solution by adapting a NAT unit independent of the switching unit in the network switching device, independently setting a CPU and peripheral circuits in the NAT unit, and independently setting a CPU in the NAT unit to independently implement NAT processing of the message. The technical solution can effectively alleviate the problem of heavy CPU burden in the switching unit, and improve the efficiency of message exchange while saving the implementation cost of the network switching device to the greatest extent.

[0059] Application scenario 1

[0060] Figure 3 FIG. 4 shows an information interaction diagram in a configuration delivery or firmware upgrade scenario applicable to an embodiment of the present invention. Figure 3 As shown, the switching unit 320 can be used to receive the NAT configuration instruction sent by the configuration terminal 310 through the standard configuration interface, and send the NAT configuration information matching the NAT configuration instruction to the NAT unit 330 through the fourth data port.

[0061] Correspondingly, the NAT unit 330 can be used to update and store the local NAT configuration table according to the received NAT configuration information.

[0062] In this embodiment, the NAT configuration table in the network switching device can be updated or set, wherein the switching unit 320 is configured with a command interface and a data interface, the command interface is used to receive instructions sent by users or upper-layer devices, and the data interface is used to transmit various data packets.

[0063] The switching unit 320 receives the NAT configuration instruction sent by the configuration terminal, ie, the upper layer device, through the standard configuration interface, ie, the instruction interface, and sends the NAT configuration information to the NAT unit 330. The NAT unit 330 updates the local NAT configuration table according to the NAT configuration information.

[0064] Optionally, the switching unit 320 is further configured to locally store the NAT configuration information when receiving the NAT configuration information from the intranet or the extranet.

[0065] When the switching unit 320 receives NAT configuration information sent from an upper layer device in the intranet or extranet, it can first store the NAT configuration information in the switching unit 320, and then further respond to the NAT configuration instruction to send the locally stored NAT configuration information to the NAT unit 330.

[0066] Optionally, the switching unit 320 may also be configured to receive a NAT unit firmware upgrade instruction issued by the configuration terminal 310 through a standard configuration interface, and issue a NAT firmware matching the NAT unit firmware upgrade instruction to the NAT unit 330 through a fifth data port.

[0067] Accordingly, the NAT unit 330 can be used to use the NAT firmware to perform firmware upgrade when receiving the NAT firmware sent by the switching unit, and when the firmware upgrade is completed, trigger the NAT unit 330 to restart the system to make the NAT firmware effective.

[0068] The relevant programs in the NAT unit 330 in the network switching device can be upgraded, wherein the switching unit 320 is configured with a command interface and a data interface, the command interface is used to receive commands sent by users or upper-layer devices, and the data interface is used to transmit messages. The switching unit receives the NAT unit firmware upgrade command issued by the configuration terminal 310, i.e., the upper-layer device, through the standard configuration interface, i.e., the command interface, and sends the matching NAT firmware, i.e., the upgrade software package, to the NAT unit 330. The NAT unit 330 then upgrades its own firmware according to the NAT firmware, and when the firmware upgrade is completed, triggers the NAT unit 330 to restart the system so that the NAT firmware takes effect.

[0069] Optionally, the switching unit 320 is further configured to locally store the NAT firmware when receiving the NAT firmware from the intranet or the extranet.

[0070] When the switching unit 320 receives the NAT firmware sent from the upper layer device of the intranet or the extranet, it can first store the NAT firmware in the switching unit 320, and then further respond to the NAT unit firmware upgrade instruction to send the NAT firmware to the NAT unit 330.

[0071] Optionally, the fourth data port may be a UART port supporting a serial communication protocol, or the fifth data port may be a UART port supporting a serial communication protocol.

[0072] The technical solution solves the problem of how to update and iterate the NAT unit by updating and storing the local NAT configuration table and upgrading the NAT firmware, thereby achieving the effect of updating the NAT configuration table and upgrading related software according to demand.

[0073] Application scenario 2

[0074] Figure 4 1 is an information interaction diagram in a NAT conversion scenario of a message applicable to an embodiment of the present invention. Figure 4 As shown, the DPDK (Data Plane Development Kit) is pre-installed in the NAT unit 430, and the VPP code is pre-installed in the DPDK.

[0075] Specifically, when a message to be forwarded is received through DPDK, the message to be forwarded is mapped to the user space; through the VPP code in the user space, a NAT result message matching the message to be forwarded is generated according to the local NAT configuration table; and the NAT result message is returned to the switching unit 420 through the DPDK.

[0076] The Data Plane Development Kit (DPDK) is a set of function libraries and drivers for fast packet processing based on Linux, which can greatly improve data processing performance and throughput, and improve the efficiency of data plane applications. The Vector Packet Processing (VPP) code is stored in user space as a normal application, and can generate NAT result messages that match the messages to be forwarded.

[0077] The technical solution of this embodiment uses the software computing function of the CPU configured in the NAT unit 430, sets up a data plane development kit of the NAT unit in the CPU, and pre-installs vector data processing code in the data plane development kit, so that the optimized NAT algorithm can be used to implement NAT conversion, so as to further improve the processing efficiency of NAT, and achieve the maximum effect improvement at the lowest cost.

[0078] Optionally, the switching unit may also be configured to, after parsing the message to be forwarded, send the message to be forwarded to the NAT unit 430 if it is determined according to the parsing result that the message to be forwarded needs to be subjected to message filtering detection;

[0079] The NAT unit 430 can also detect whether the message to be forwarded meets the message filtering conditions according to the local message filtering configuration table when receiving the message to be forwarded: if so, the message to be forwarded is directly filtered; otherwise, the message to be forwarded is returned to the switching unit 420; the switching unit 420 can also forward the message to be forwarded to the matching external network 440 or internal network 410 according to the local forwarding table when receiving the message to be forwarded returned by the NAT unit 430.

[0080] That is to say, in addition to performing the IP address translation function, the NAT unit 430 can also filter the forwarding messages.

[0081] The advantage of this setting is that it enriches the business functions of the NAT unit and fully utilizes the independent CPU resources of the NAT unit.

[0082] It needs to be explained again that the technical solution of the present application uses an external CPU to implement separate NAT processing. Considering that the processing function of the external CPU is relatively powerful, it is also possible to consider diverting other tasks performed by the CPU in the original switching unit to the CPU for auxiliary processing, so as to further improve the flexible allocation of functions of the entire network switching device, thereby optimizing the computing and processing efficiency of the network switching device.

[0083] It is worth noting that in the embodiment of the above-mentioned network device, the various units and modules included are only divided according to functional logic, but are not limited to the above-mentioned division, as long as the corresponding functions can be realized; in addition, the specific names of the functional units are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention.

[0084] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A network switching device, characterized in that: include: Switching unit and network address translation NAT unit; NAT unit consists of CPU and peripheral circuits; The switching unit is used to parse the message to be forwarded when receiving the message to be forwarded from the intranet or the extranet, and if it is determined according to the parsing result that the message to be forwarded needs to be NAT converted, the message to be forwarded is sent to the NAT unit; The NAT unit is used to generate a NAT result message matching the message to be forwarded according to the local NAT configuration table when receiving the message to be forwarded, and return the NAT result message to the switching unit; The switching unit is further configured to forward the NAT result message to a matching external network or internal network according to a local forwarding table when receiving the NAT result message returned by the NAT unit; The switching unit is further used for: after parsing the message to be forwarded, if it is determined according to the parsing result that the message to be forwarded needs to be subjected to message filtering detection, sending the message to be forwarded to the NAT unit; The NAT unit is also used for: upon receiving a message to be forwarded, detecting whether the message to be forwarded satisfies a message filtering condition according to a local message filtering configuration table; if so, directly filtering the message to be forwarded; otherwise, returning the message to be forwarded to the switching unit; The switching unit is further used for: when receiving the message to be forwarded returned by the NAT unit, forwarding the message to be forwarded to a matching external network or internal network according to the local forwarding table.

2. The network switching device according to claim 1, characterized in that: The switching unit exchanges messages with the external network through the first data port, exchanges messages with the internal network through the second data port, and exchanges messages with the NAT unit through the third data port.

3. The network switching device according to claim 1, characterized in that: The switching unit is also used for: receiving a NAT configuration instruction sent by a configuration terminal through a standard configuration interface, and sending NAT configuration information matching the NAT configuration instruction to the NAT unit through a fourth data port; The NAT unit is further used to update and store the local NAT configuration table according to the received NAT configuration information.

4. The network switching device according to claim 3, characterized in that: The switching unit is also used for: When receiving NAT configuration information from an intranet or an extranet, the NAT configuration information is stored locally.

5. The network switching device according to claim 1, characterized in that: The switching unit is also used for: Receiving a NAT unit firmware upgrade instruction sent by a configuration terminal through a standard configuration interface, and sending a NAT firmware matching the NAT unit firmware upgrade instruction to the NAT unit through a fifth data port; The NAT unit is also used for: when receiving the NAT firmware sent by the switching unit, using the NAT firmware to perform firmware upgrade, and when the firmware upgrade is completed, triggering the NAT unit to restart the system so that the NAT firmware takes effect.

6. The network switching device according to claim 5, characterized in that: The switching unit is also used for: When receiving the NAT firmware from the intranet or the extranet, the NAT firmware is stored locally.

7. The network switching device according to claim 3, characterized in that: The fourth data port is a UART port supporting a serial communication protocol.

8. The network switching device according to claim 5, characterized in that: The fifth data port is a UART port supporting a serial communication protocol.

9. The network switching device according to any one of claims 1 to 6, characterized in that: A data plane development kit DPDK is pre-installed in the NAT unit, and a vector packet processing VPP code is pre-installed in the DPDK.

10. The network switching device according to claim 9, characterized in that: The NAT unit is specifically used for: When a message to be forwarded is received through DPDK, the message to be forwarded is mapped to the user space; Through the VPP code in the user space, a NAT result message matching the message to be forwarded is generated according to the local NAT configuration table; The NAT result message is returned to the switching unit through the DPDK.

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