CN112235211B

CN112235211B - UPF system based on cooperation of switch and UPF equipment and control method thereof

Info

Publication number: CN112235211B
Application number: CN202010913569.2A
Authority: CN
Inventors: 金鹰
Original assignee: Guangzhou Digital Science And Technology Co ltd
Current assignee: Guangzhou Digital Science And Technology Co ltd
Priority date: 2020-09-03
Filing date: 2020-09-03
Publication date: 2022-01-21
Anticipated expiration: 2040-09-03
Also published as: CN112235211A

Abstract

The invention discloses a UPF system based on the cooperation of a switch and UPF equipment and a control method thereof, which are applied to the field of communication equipment and comprise the UPF equipment and the switch, wherein the UPF equipment is used for receiving a GTP-C message, establishing a GTP session according to the GTP-C message, determining a forwarding strategy of the GTP session and issuing the forwarding strategy; the exchanger management CPU is used for transmitting information between the UPF equipment and the exchange chip; the switching chip is used for acquiring a GTP-C message and a GTP-U message from an input port, forwarding the GTP-C message to the UPF device through the switch management CPU, receiving the forwarding strategy issued by the UPF device from the switch management CPU, forwarding the GTP-U message to an output port according to the forwarding strategy, and carrying out charging statistics. The invention can complete the processing of large-scale GTP messages under the condition of not greatly increasing the hardware cost.

Description

UPF system based on cooperation of switch and UPF equipment and control method thereof

Technical Field

The invention relates to communication equipment, in particular to a UPF system based on cooperation of a switch and UPF equipment and a control method thereof.

Background

The current UPF device completes the forwarding and charging processing of GTP data message based on the CPU of X86, considering the performance problem of single CPU, the other UPF device is completed by multi-core CPU, even the combination of multiple CPUs. The maximum capability is also 25Gbps for DPDK pure software acceleration scheme for the x86 platform. With the explosion of 5G application with ultra-large bandwidth and the increase of video application, tens of times of requirements are put on the forwarding capability of UPF equipment, so that the CPU and a software acceleration scheme cannot meet the future requirements.

The existing UPF equipment realizes the forwarding and charging processing of GTP messages based on a DPDK pure software acceleration scheme of an x86 platform, and if the capacity needs to be increased, the configuration or the number of CPUs needs to be increased, which causes the cost of the UPF equipment to be greatly increased.

Disclosure of Invention

To solve at least one of the above-mentioned technical problems, the present invention is directed to: a UPF system based on the cooperation of a switch and UPF equipment and a control method thereof are provided, so as to meet the large-scale forwarding and charging processing of GTP data messages under the condition of not greatly increasing the hardware cost.

In a first aspect, an embodiment of the present invention provides:

a UPF system based on the cooperation of a switch and UPF equipment comprises the UPF equipment and the switch, wherein the switch comprises an output port, an input port, a switch management CPU and a switch chip;

the UPF equipment is used for receiving a GTP-C message, establishing a GTP session according to the GTP-C message, determining a forwarding strategy of the GTP session, and issuing the forwarding strategy;

the switch management CPU is used for forwarding information between the UPF equipment and the switch chip;

the switching chip is used for acquiring a GTP-C message and a GTP-U message from an input port, forwarding the GTP-C message to the UPF device through the switch management CPU, receiving the forwarding strategy issued by the UPF device from the switch management CPU, forwarding the GTP-U message to an output port according to the forwarding strategy, and carrying out charging statistics.

In some embodiments, the switch chip is further configured to forward, through the switch management CPU, a part of the GTP-U packet to the UPF device, and the UPF device is further configured to process the part of the GTP-U packet.

In some embodiments, after receiving the forwarding policy, the switch chip updates the forwarding table entry and the GTP tunnel decapsulation table entry according to the forwarding policy.

In some embodiments, the policy for forwarding the UPF packet to the output port or the UPF device by the switch chip according to the forwarding policy is:

searching in a forwarding table entry according to a GTP-U message to be forwarded, and forwarding the GTP-U message to be forwarded to a hit output port under the condition that the GTP-U message to be forwarded hits the hit output port; and under the condition that the output port is not searched, the GTP-U message to be forwarded is forwarded to the UPF equipment through the switch management CPU.

In some embodiments, the switch chip forwards a GTP-C message or a GTP-U message to the switch management CPU through a data channel, and the switch management CPU issues a forwarding policy of the GTP session to the switch chip through a management channel;

the switch management CPU and the UPF equipment communicate through an RPC interface.

In some embodiments, the switching chip performs billing based on built-in stats statistics.

In some embodiments, the switch chip edits the GTP-U packet before forwarding the GTP-U packet to the output port, where the editing includes: and at least one of a TEID field, an extension Header, MAC addresses of inner and outer layers of GTP, an IP address and a UDP port number in the GTP-Header.

In some embodiments, the UPF device is configured to process a GTP-U packet of a preset type.

In some embodiments, the UPF device processes the GTP-C packet and a GTP-U packet of a preset type by running a GTP protocol stack handler.

In a second aspect, an embodiment of the present invention provides:

a control method of a UPF system based on cooperation of a switch and a UPF device is disclosed, the system comprises the UPF device and the switch, the switch comprises an output port, an input port, a switch management CPU and a switch chip, the method comprises the following steps:

the switching chip receives a GTP-C message from an input port;

the switching chip forwards the GTP-C message to the UPF equipment through the switch management CPU;

the UPF equipment establishes a GTP session according to the GTP-C message and determines a forwarding strategy of the GTP session;

the UPF equipment issues the forwarding strategy to the switch chip through the switch management CPU;

and the switching chip forwards the GTP-U message acquired from the input port to the output port according to the forwarding strategy and performs charging statistics.

The embodiment of the invention has the beneficial effects that: the UPF equipment is used for processing the GTP-C message, a GTP session is established, a forwarding strategy is determined, the forwarding and charging statistics of the GTP-U message are unloaded on the processing of a switching chip, and the processing capability and the forwarding bandwidth of the switching chip are used for realizing the processing of the large-scale GTP message.

Drawings

Fig. 1 is a schematic application diagram of a UPF system based on cooperation of a switch and a UPF device according to an embodiment of the present invention;

fig. 2 is a block diagram of a UPF system based on cooperation of a switch and a UPF device according to an embodiment of the present invention;

fig. 3 is a schematic data flow diagram of a UPF system based on cooperation of a switch and a UPF device in an initialization stage according to an embodiment of the present invention;

fig. 4 is a schematic diagram of data flow in forwarding policy allocation of a UPF system based on cooperation of a switch and a UPF device according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a data flow when a UPF system based on cooperation of a switch and a UPF device forwards a GTP-U packet according to an embodiment of the present invention;

fig. 6 is a flowchart of a method for controlling a UPF system based on cooperation of a switch and a UPF device according to an embodiment of the present invention.

Detailed Description

The invention is further described with reference to the drawings and the specific examples.

The following key terms appear first to be explained:

GTP: GPRS tunneling protocol, GPRS tunneling protocol.

GTP-C: control plane of GPRS tunneling protocol.

GTP-U: user plane of GPRS tunneling protocol.

UPF: user Plane Function.

RPC: and (4) remote procedure call.

Referring to fig. 1 and fig. 2, the present embodiment discloses a UPF system based on cooperation of a switch and a UPF device, where the device is applied in an application scenario shown in fig. 1, where the scenario may be one scenario in 5G communication, the system in the present embodiment includes a UPF device and a switch, where the switch includes an output port, an input port, a switch management CPU, and a switch chip;

as shown in fig. 3, a GTP message enters the switch chip through the input port, the switch chip forwards the GTP-C message to the switch management CPU through the data channel, and the switch management CPU sends the message to the UPF device, as shown in fig. 4, the UPF device establishes a GTP session according to the GTP-C message, determines a forwarding policy of the GTP session, and then issues the forwarding policy to the switch chip through the management channel of the switch management CPU. After the switch obtains the forwarding strategy, the GTP-U message can be processed. When building GTP conversation, it needs to send GTP-Reply message through exchange chip.

specifically, in the present embodiment, the switch management CPU functions as data between the UPF device and the switch chip that are forwarded.

When the switching chip does not acquire the forwarding policy of the GTP session, all GTP-U messages and GTP-C messages are forwarded to the UPF device through the switch management CPU for processing, and after the forwarding policy of the GTP session is acquired, part or all of the GTP-U messages are processed by the switching chip, and at this time, as shown in fig. 5, the GTP-U messages are acquired from the input port and forwarded to the output port after the processing is completed in the switching chip. Specifically, in some embodiments, which GTP-U messages are processed in the switch chip and which GTP-U messages are processed in the UPF device may be determined according to the occurrence ratio of the GTP-U messages of each type. For GTP-U messages with a high occurrence ratio, i.e. a large number, it may be configured in the switch chip for processing, and for GTP-U messages with a low occurrence ratio, i.e. a small number, it may be configured in the UPF device for processing. GTP charging statistics, speed limit and other functions are completed by the switching chip. It should be understood that, when the switch chip forwards a GTP-U packet, it will perform decapsulation and encapsulation processing according to the forwarding policy, and forward the GTP-U packet to a certain output port.

The above description of the technology shows that, the UPF device is used to process the GTP-C packet, and establish the GTP session and determine the forwarding policy, and the forwarding and charging statistics of the GTP-U packet are offloaded to the switch chip processing, and the large-scale GTP packet processing is implemented by using the processing capability and forwarding bandwidth of the switch chip itself.

In this embodiment, only some types of GTP-U packets may be processed in the switch chip, and other GTP-U packets may be forwarded to the UPF device for processing.

As shown in Table 1, the GTP-U message types occupying most of the whole area are put into the switch chip to be processed according to the occurrence possibility of the GTP-U message. For example, in this embodiment, GTP-U messages 41 and 45 are processed by the switch chip, while the others are processed by the switch management CPU. Certainly, when configuring which types of GTP-U packets are processed by the switch chip, besides the possibility of occurrence of the GTP-U packets, the difficulty of processing the GTP-U packets needs to be considered, and the GTP-U packets that need more resources during processing may also be processed in the switch chip. In this embodiment, by handing part of the GTP-U packet to the UPF device for processing, the CPU resource of the UPF device can be fully utilized, and the load of the UPF device and the switch chip can be optimized by allocating the above processing according to the actual situation.

TABLE 1

Specifically, after completing establishment of the GTP session, the switch chip receives the forwarding policy of the UPF device and issues the forwarding policy to the corresponding forwarding table entry (e.g., ACL, routing table entry) in the switch chip, and the GTP tunnel decapsulation table entry, GTP tunnel Next-hop.

In this embodiment, the forwarding policy is to search a forwarding port of a GTP-U packet in a forwarding entry, and when no hit result is found, it indicates that the packet belongs to a processing type of the UPF device, or the GTP-U packet does not have a corresponding GTP forwarding policy and needs to be processed by the UPF device. By the strategy, the GTP-U message cannot be omitted to a certain extent.

In some embodiments, the switch chip forwards a GTP-C message or a GTP-U message to the switch management CPU through a data channel, and the switch management CPU issues a forwarding policy of the GTP session to the switch chip through a management channel; the data channel and the management channel are distinguished, and the uplink and downlink bandwidths between the data channel and the management channel can be effectively divided so as to reduce delay.

In the UPF device and the switch for processing the GTP message in this embodiment, decoupling between the UPF device and the switch is completed through a standard RPC interface, and the UPF and the switch support management and control of the RPC interface of the switch management CPU by the UPF through physical port interconnection, support various RPC interfaces and modes such as http, openflow, netconf, gRPC, CLI, and SNMP, and further support forwarding GTP traffic that is not offloaded to the switch chip to the UPF device through the physical port interconnection channel for processing.

In some embodiments, the switching chip performs billing based on built-in stats statistics. In the embodiments, the originally built-in stats statistical function of the switching chip can be used for charging, so that the extra overhead can be reduced, and the development difficulty is also reduced.

In some embodiments, the UPF device processes the GTP-C packet and a GTP-U packet of a preset type by running a GTP protocol stack handler. Referring to fig. 2, in this embodiment, the UPF device runs a GTP protocol stack handler, and may complete a GTP processing procedure by using a GTP protocol stack.

Embodiments of the present invention will be fully described with reference to fig. 2 to 5. As shown in fig. 2, the UPF system of the present embodiment mainly includes two devices: UPF equipment and switch, wherein, the switch includes management CPU and switching chip. The switching chip of the switch adopted in this embodiment has full wire speed forwarding capability for GTP packets, and the difference between the forwarding bandwidth of the switching chip with the same cost and the performance of the current CPU for processing GTP packets is hundreds of times.

As shown in fig. 2, the switch and the device running the UPF protocol stack communicate with each other through a switch physical port connection, so that the interconnected link bearing switch manages traffic between the CPU and the UPF device, and includes: a GTP data message forwarding channel and a GTP forwarding strategy control channel. The data channel is used for forwarding the GTP message received by the switch to a protocol stack of the UPF device after the GTP message is searched and processed, or forwarding the GTP message sent by the UPF protocol stack to a switch chip for forwarding and searching processing. The management channel is used for the UPF protocol stack to negotiate and establish the GTP session, and configures the forwarding strategy of the GTP session to the switch management CPU in an RPC mode, and the switch software operated by the switch management CPU needs to map the received GTP forwarding strategy to different forwarding table entries of the switch chip and complete the charging function by the GTP message statistics of the switch chip. The UPF equipment comprises a UPF management CPU, a UPF chip and a UPF management CPU, wherein the UPF management CPU is used for operating switch system software, needs to support RPC docking with UPF equipment and can support mapping of a GTP forwarding strategy configured by UPF to a forwarding table entry of the switching chip; the switching chip is used for operating a forwarding plane of the UPF and unloading the functions of searching, limiting speed, charging and the like of a forwarding strategy for processing the GTP-U message; and the UPF equipment runs a GTP protocol stack and supports the configuration of the forwarding strategy for the butt joint of the RPC interfaces of the switch.

In an initial state, the UPF device in this embodiment configures a physical network based on a switch, such as a port IP and a route, through an RPC channel, and is configured to complete interworking of the ipunderly network (gtcoverage tunnel establishment depends on the underly network), and open a data channel and a management channel between a switch chip and the CPU.

As shown in fig. 3, in a default situation, the UPF configures a switch forwarding policy, the switch chip sends the received GTP message to the GTP protocol stack of the UPF device for processing, waits for the establishment of a GTP session of the UPF protocol stack and issues the forwarding policy to the switch management CPU, and the switch management CPU maps the UPF forwarding configuration to the forwarding table entry of the switch chip.

As shown in fig. 4, after completing the establishment of the GTP session, the switch chip receives the corresponding chip forwarding table entry sent by the switch management CPU, which includes but is not limited to a GTP tunnel decapsulation table entry, a GTP tunnel editing Nexthop, stats statistics, Policer speed limit, and the like.

As shown in fig. 5, when the subsequent received packet of the GTP session is forwarded on the switch chip, the forwarding policy lookup is performed. If the forwarding table entry is searched, forwarding to a corresponding output port according to the search result, updating stats statistics, and finishing the editing of the GTP message according to the search result, wherein the editing capability of fields such as TEID, an expansion head, MAC addresses of inner layers and outer layers of GTP, IP addresses, UDP port numbers and the like in the GTP Header is included. If the forwarding table entry corresponding to the missing switching chip is searched, the packet of the data stream is forwarded to the UPF device running the GTP protocol stack for processing, which is the same as the path for forwarding the GTP packet to the UPF device by the switching chip in fig. 3.

For the scheme of cooperation of the switch and the UPF equipment, the UPF equipment manages and controls the switch through a physical port interconnection channel of the switch, and the specific management mode of the scheme of the invention supports various RPC interfaces and modes such as http, openflow, netconf, gRPC, CLI, SNMP and the like.

Referring to fig. 6, the present embodiment discloses a method for controlling a UPF system based on cooperation of a switch and a UPF device, where the system includes the UPF device and the switch, the switch includes an output port, an input port, a switch management CPU, and a switch chip, and the method includes the following steps:

step 610, the switching chip receives a GTP-C message from an input port;

step 620, the switch chip forwards the GTP-C message to the UPF device through the switch management CPU;

step 630, the UPF device establishes a GTP session according to the GTP-C packet and determines a forwarding policy of the GTP session;

step 640, the UPF device issues the forwarding policy to the switch chip through the switch management CPU;

step 650, the switch chip forwards the GTP-U packet obtained from the input port to the output port according to the forwarding policy, and performs charging statistics.

The step numbers in the above method embodiments are set for convenience of illustration only, the order between the steps is not limited at all, and the execution order of each step in the embodiments can be adapted according to the understanding of those skilled in the art.

While the preferred embodiments of the present invention have been illustrated and described, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A UPF system based on the cooperation of a switch and a user plane function UPF device is characterized by comprising the UPF device and the switch, wherein the switch comprises an output port, an input port, a switch management CPU and a switching chip;

the UPF equipment is used for receiving a control plane GTP-C message of a tunneling protocol GPRS, establishing a GPRS tunneling protocol GTP session according to the GTP-C message, determining a forwarding strategy of the GTP session and issuing the forwarding strategy;

the switching chip is used for acquiring a GTP-C message and a user plane GTP-U message of a tunneling protocol GPRS from an input port, forwarding the GTP-C message to the UPF equipment through the switch management CPU, receiving the forwarding strategy issued by the UPF equipment from the switch management CPU, forwarding the GTP-U message to an output port according to the forwarding strategy, and carrying out charging statistics;

the switching chip forwards a GTP-C message or a GTP-U message to the switch management CPU through a data channel, and the switch management CPU issues a forwarding strategy of the GTP session to the switching chip through a management channel;

the switch management CPU and the UPF equipment communicate through a Remote Procedure Call (RPC) interface.

2. The UPF system based on the cooperation of the switch and the UPF device, as claimed in claim 1, wherein the switch chip is further configured to forward a part of the GTP-U packet to the UPF device through the switch management CPU, and the UPF device is further configured to process a part of the GTP-U packet.

3. The UPF system based on the cooperation of the switch and the UPF device, as claimed in claim 2, wherein the switch chip updates the forwarding table and the GTP tunnel decapsulation table according to the forwarding policy after receiving the forwarding policy.

4. The UPF system based on the cooperation of the switch and the UPF device, according to claim 3, wherein the strategy for the switch chip to forward the UPF packet to the output port or the UPF device according to the forwarding strategy is as follows:

5. The UPF system based on the cooperation of the switch and the UPF device as claimed in claim 1, wherein the switching chip performs charging based on a built-in stats statistical function.

6. The UPF system based on the cooperation of the switch and the UPF device, according to claim 1, wherein the switch chip edits the GTP-U packet before forwarding the GTP-U packet to the output port, wherein editing comprises: and at least one of a TEID field, an extension Header, MAC addresses of inner and outer layers of GTP, an IP address and a UDP port number in the GTP-Header.

7. The UPF system based on the cooperation of the switch and the UPF device, according to claim 1, wherein the UPF device is configured to process a GTP-U packet of a preset type.

8. The UPF system based on the cooperation of the switch and the UPF device, as claimed in claim 7, wherein the UPF device processes the GTP-C packet and a GTP-U packet of a preset type by running a GTP protocol stack handler.

9. A control method of a UPF system based on cooperation of a switch and UPF equipment is characterized in that the system comprises the UPF equipment and the switch, the switch comprises an output port, an input port, a switch management CPU and a switching chip, and the method comprises the following steps:

the switching chip receives a GTP-C message from an input port;

the switching chip forwards the GTP-U message acquired from the input port to the output port according to the forwarding strategy and carries out charging statistics;