CN114666279A

CN114666279A - Method and system for issuing PCC session management policy in 5G system

Info

Publication number: CN114666279A
Application number: CN202210105596.6A
Authority: CN
Inventors: 曾志高
Original assignee: Ankexun Fujian Technology Co ltd
Current assignee: Ankexun Fujian Technology Co ltd
Priority date: 2022-01-28
Filing date: 2022-01-28
Publication date: 2022-06-24
Anticipated expiration: 2042-01-28
Also published as: CN114666279B

Abstract

The invention discloses a method and a system for issuing a PCC conversation management strategy in a 5G system.A strategy control network element firstly acquires the latest flow classification rule and the corresponding PCC rule configuration after the QoS rule issued to a user terminal by the strategy control network element is changed; if the number of the flow classification rules is larger than the preset number, creating a plurality of PCC rules with the same PCC rule configuration except for different flow classification rule parameters, respectively adding the description information of the flow classification rules into the flow classification rule parameters of the PCC rules, and keeping the number of the flow classification rules identified by each PCC rule smaller than or equal to the preset number; and adding all PCC rules into one PCC rule table, and sending the PCC rule table to the session management network element so that the session management network element completely sends all flow classification rules in the PCC rules to the user terminal. The invention ensures that the number of the packet filters received by the session management network element each time is not more than the preset number, and ensures that the session management network element can correctly and completely process the packets.

Description

Method and system for issuing PCC session management policy in 5G system

Technical Field

The invention relates to the technical field of mobile communication, in particular to a method and a system for issuing a Policy Control and Charging (PCC) session management policy in a 5G system.

Background

In a 5G (fifth generation mobile communication technology) system, a QoS model is established based on QoS flows. Qfi (QoS Flow id) is used to identify one QoS Flow in a 5G system. The QoS flow is the minimum granularity for realizing QoS differentiation guarantee in a 5G system, different QoS flows correspond to different QoS forwarding treatments, and application data flows with similar requirements (such as bandwidth and delay) properties are generally mapped to the same QoS flow and have the same QoS attribute and forwarding treatment. The QoS flow is controlled by an SMF (session management network element), which may be pre-configured or established through a PDU session setup and modification procedure.

For uplink data, the UE (user terminal) matches data packets according to the QoS rule, and the data packets are transmitted upwards from the matched QoS stream and the corresponding channel; for downlink data, the UPF (user plane function) matches the data according to the PDR (packet detection rule), and packets are transmitted downward from the matched QoS streams and their corresponding channels. If a packet does not match any of the QoS rules or PDRs, the packet is dropped by the UE or the UPF.

In the 5G system, the QoS Rule and PDR mentioned above are both issued by a pcc (policy Control and charging) Control network element PCF in a 5G core network to an SMF, and then the SMF Control element PCF is converted into a corresponding QoS Rule and issued to a UE side for execution, and at the same time, the QoS Rule is converted into a PDRs Rule and sent to a UPF for QoS Control of a downlink message.

In 3GPP protocol 2401, it is specified that the number of Packet filters (Packet filters) included in a QoS Rule issued to a UE should be less than or equal to a preset number, and at present, the preset number is 15, that is, the SMF processes Packet filters in a QoS Rule according to a maximum of 15. If the same QoS Rule contains more than 15 Packet filters, the SMF cannot normally process or cannot completely complete processing and forwarding. However, in the actual requirement, the number of Packet filters of the same type that may need to be added for one UE is far more than 15, for example, a terminal is limited to access a specific APP, the APPs may have several tens of IPs on the service network (the IPs may be queried according to APP names by DPI servers, or may be dynamically or statically configured by other application modules), the IPs of the servers corresponding to the APPs need to be added to a Packet Filter set as a filtering rule of data flows, and are issued to the UE and the UPF module to perform QoS control (if access is limited in this example, the forwarding rule is set to discard the Packet), so as to achieve the purpose of limiting the UE from accessing the APPs.

Then, in the case that the QoS Rule with the same QoS attribute sent to the UE contains more than the preset number of Packet filters, how the PCF module performs the PCC policy issued to the SMF can ensure that the SMF performs correct and complete processing, and then forwards the QoS Rule to the UE and the UPF module, thereby ensuring correct classification detection of the terminal service data stream and QoS resource allocation? There is currently no effective solution.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: a method and a system for issuing PCC session management policy in a 5G system are provided, which ensure that a session management network element can correctly and completely process when packet filters to be issued exceed a preset number.

In order to solve the problems, the invention adopts the following scheme:

a method for issuing PCC session management policy in a 5G system includes the following steps:

s1, after the QoS strategy sent to the user terminal by the strategy control network element is changed, obtaining the latest flow classification rule and the corresponding PCC rule configuration;

s2, if the number of the flow classification rules is greater than a preset number, the policy control network element creates a plurality of PCC rules with the same PCC rule configuration except for different flow classification rule parameters, respectively adds description information of the flow classification rules to the flow classification rule parameters of the PCC rules, and keeps the number of the flow classification rules identified by each PCC rule less than or equal to the preset number, where the preset number is the single maximum processing amount in the session management network element;

s3, the policy control network element adds all the PCC rules to a PCC rule table, and sends the PCC rule table to the session management network element, so that the session management network element completely issues all the flow classification rules in the PCC rules to the user terminal.

In order to solve the above problems, the present invention adopts another scheme as follows:

a system for issuing PCC session management policy in a 5G system comprises a policy control network element and a session management network element, wherein the policy control network element comprises a first memory, a first processor and a computer program which is stored on the first memory and can be run on the first processor, and the first processor implements the following steps when executing the computer program:

s1, obtaining the latest flow classification rule and the corresponding PCC rule configuration after the QoS strategy sent to the user terminal is changed;

s2, if the number of the flow classification rules is greater than a preset number, creating a plurality of PCC rules with the same PCC rule configuration except for different flow classification rule parameters, respectively adding description information of the plurality of flow classification rules to the flow classification rule parameters of the plurality of PCC rules, and keeping the number of the flow classification rules identified by each PCC rule less than or equal to the preset number, where the preset number is the single maximum processing amount in a session management network element;

s3, adding all the PCC rules to a PCC rule table, and sending the PCC rule table to the session management network element, so that the session management network element completely issues all the flow classification rules in the PCC rules to the user terminal.

In conclusion, the beneficial effects of the invention are as follows: when the number of flow classification rules is larger than the preset number, such as 15, that is, the packet filters that the session management network element needs to issue to the user terminal are larger than the preset number, by creating a plurality of PCC rules with the same configuration, the PCC rules are used for respectively encapsulating all the flow classification rules, so that the number of the flow classification rules of each PCC rule does not exceed the preset number, and further, the packet filters that the session management network element needs to normally process and issue each time are not larger than the preset number, which conforms to the specification in 3GPP protocol 2401, and the session management network element can be guaranteed to correctly and completely process.

Drawings

Fig. 1 is a schematic diagram illustrating steps of a method for issuing a PCC session management policy in a 5G system according to an embodiment of the present invention;

fig. 2 is a schematic flowchart of a cooperation of network elements in a method for issuing a PCC session management policy in a 5G system according to an embodiment of the present invention;

fig. 3 is a schematic flowchart of a new PCC session management policy in a method for issuing a PCC session management policy in a 5G system according to an embodiment of the present invention;

fig. 4 is a block diagram illustrating a system for issuing a PCC session management policy in a 5G system according to an embodiment of the present invention.

Description of reference numerals:

1. a system for sending PCC conversation management strategy in 5G system; 2. a policy control network element; 3. a first memory; 4. a first processor; 5. a session management network element; 6. a second memory; 7. a second processor.

Detailed Description

In order to explain technical contents, achieved objects, and effects of the present invention in detail, the following description is made with reference to the accompanying drawings in combination with the embodiments.

Referring to fig. 1 to 4, a method for issuing a PCC session management policy in a 5G system includes the following steps:

s1, after the QoS strategy sent to the user terminal by the strategy control network element 2 is changed, obtaining the latest flow classification rule and the corresponding PCC rule configuration;

s2, if the number of the flow classification rules is greater than the preset number, the policy control network element 2 creates a plurality of PCC rules with the same PCC rule configuration except for different flow classification rule parameters, respectively adds description information of the flow classification rules to the flow classification rule parameters of the PCC rules, and keeps the number of the flow classification rules identified by each PCC rule less than or equal to the preset number, where the preset number is the single maximum processing amount in the session management network element 5;

s3, the policy control network element 2 adds all the PCC rules to a PCC rule table, and sends the PCC rule table to the session management network element 5, so that the session management network element 5 completely issues all the flow classification rules in the PCC rules to the user terminal.

From the above description, the beneficial effects of the present invention are: when the number of flow classification rules is larger than a preset number, such as 15, that is, a packet filter that a session management network element 5 needs to issue to a user terminal is larger than the preset number, a plurality of PCC rules with the same configuration are created to be used for respectively encapsulating all the flow classification rules, so that the number of the flow classification rules of each PCC rule does not exceed the preset number, and further, the packet filters that the session management network element 5 needs to normally process and issue each time are not larger than the preset number, which conforms to the specification in 3GPP protocol 2401, and thus, the session management network element 5 can correctly and completely process.

Further, the step S2 is specifically:

s21, if the number of the flow classification rules is greater than the preset number, the policy control network element 2 divides all the flow classification rules into a plurality of groups of flow classification rule groups in a grouping manner that the preset number is one group and the remaining unsatisfied preset number is also one group;

s22, the policy control network element 2 creates one PCC rule according to the PCC rule configuration, clones the PCC rule to obtain a plurality of PCC rules, where only the flow classification rule parameters are different and the number of PCC rules is equal to the number of packet groups of the flow classification rule, and sets an identifier name for each PCC rule;

s23, the policy control network element 2 associates the flow classification rule packet with the PCC rule one by one, and adds the description information of all the flow classification rules of each flow classification rule packet to the flow classification rule parameters of the corresponding PCC rule.

As can be seen from the above description, a plurality of PCC rules are created in a cloning manner, and are used for sub-packaging description information of a plurality of flow classification rules, so that packet filters in each PCC rule issued to the session management network element 5 do not exceed a preset number, the session management network element 5 does not need to be modified, additional interactive signaling does not need to be added, and the session management network element 5 and other interfaces are ensured to be intercommunicated, and the compatibility is good.

Further, the step S3 further includes:

the policy control network element 2 sends a policy management update notification to the session management network element 5 to notify the session management network element 5 that the PCC session management policy changes and enable the session management network element 5 to process the PCC rule table according to the PCC session management policy corresponding to the PCC rule table.

As can be seen from the above description, after the session management policy changes, the policy control network element 2 sends a policy management update notification to notify the session management network element 5, so that the policy control network element can make a corresponding processing policy in time, and can correctly receive and process the PCC rule issued by the policy management network element.

Further, before the step S1 and the step S2, the method further includes:

the policy control network element 2 determines whether the number of the flow classification rules is greater than a preset number, if so, the step S2 is executed, otherwise, a PCC rule is created according to the PCC rule configuration, the description information of each flow classification rule is added to the flow classification rule parameters of the PCC rule, and the step S3 is executed.

As can be seen from the above description, when the number of the flow classification rules does not exceed the preset number, the flow classification rules are placed in the same PCC rule, and are matched with the cloning mechanism, and the number of the flow classification rules is flexibly changed according to the number of the flow classification rules, so as to ensure that the session management network element 5 can correctly and completely process the packet filter.

Further, the processing, by the session management network element 5, the PCC rule table according to the PCC session management policy corresponding to the PCC rule table specifically includes:

the session management network element 5 receives the PCC rule table and associates all the PCC rules included in the PCC rule table with the same QoS flow identity;

the session management network element 5 sequentially converts each PCC rule in the PCC rule table into an uplink service flow classification rule and a downlink service flow classification rule;

and the session management network element 5 sends all the downlink service flow classification rules to a user plane function, and sends all the uplink service data flow classification rules to the user terminal.

As can be seen from the above description, the session management network element 5 performs corresponding processing on the received PCC rule table according to the PCC session management policy, so that all flow classification rules in all PCC rules belonging to the same session can be processed and forwarded to the same user terminal.

Referring to fig. 4, a system 1 for issuing a PCC session management policy in a 5G system includes a policy control network element 2 and a session management network element 5, where the policy control network element 2 includes a first memory 3, a first processor 4, and a computer program stored in the first memory 3 and operable on the first processor 4, and when the first processor 4 executes the computer program, the following steps are implemented:

s2, if the number of the flow classification rules is greater than a preset number, creating a plurality of PCC rules having the same PCC rule configuration except for different flow classification rule parameters, respectively adding description information of the plurality of flow classification rules to the flow classification rule parameters of the plurality of PCC rules, and keeping the number of the flow classification rules identified by each PCC rule less than or equal to the preset number, where the preset number is the single maximum processing amount in the session management network element 5;

s3, adding all the PCC rules to one PCC rule table, and sending the PCC rule table to the session management network element 5, so that the session management network element 5 completely issues all the flow classification rules in the PCC rules to the user terminal.

From the above description, the beneficial effects of the present invention are: when the number of flow classification rules is larger than a preset number, for example, 15, that is, a packet filter that a session management network element 5 needs to issue to a user terminal is larger than the preset number, a plurality of PCC rules with the same configuration are created to be used for respectively encapsulating all the flow classification rules, so that the number of the flow classification rules of each PCC rule does not exceed the preset number, and further, the packet filters that the session management network element 5 needs to normally process and issue each time are not larger than the preset number, which conforms to the specification in 3GPP protocol 2401, and thus, the session management network element 5 can correctly and completely process.

Further, the step S2 is specifically:

s21, if the number of the flow classification rules is larger than the preset number, dividing all the flow classification rules into a plurality of groups of flow classification rule groups in a grouping mode that the preset number is one group and the remaining number is less than the preset number and is also one group;

s22, creating one PCC rule according to the PCC rule configuration, cloning the PCC rule to obtain a plurality of PCC rules with different flow classification rule parameters and the number equal to the number of the flow classification rule packet groups, and setting an identification name for each PCC rule;

s23, the flow classification rule groups are in one-to-one correspondence with the PCC rules, and the description information of all the flow classification rules of each flow classification rule group is added into the flow classification rule parameters of the corresponding PCC rules.

Further, the step S3 further includes:

sending a policy management update notification to the session management network element 5, so as to notify the session management network element 5 that a PCC session management policy changes and enable the session management network element 5 to process the PCC rule table according to the PCC session management policy corresponding to the PCC rule table.

As can be seen from the above description, after the session management policy changes, a policy management update notification is sent to notify the session management network element 5, so that the session management network element can make a corresponding processing policy in time, and it is ensured that the PCC rule issued by the policy management network element can be correctly received and processed.

Further, between the step S1 and the step S2, the method further includes:

judging whether the number of the flow classification rules is larger than a preset number, if so, executing the step S2, otherwise, creating one PCC rule according to the PCC rule configuration, adding the description information of each flow classification rule to the flow classification rule parameters of the PCC rule, and executing the step S3.

Further, the session management network element 5 comprises a second memory 6, a second processor 7 and a computer program stored on the second memory 6 and executable on the second processor 7, and the second processor 7 implements the following steps when executing the computer program:

receiving the PCC rule table and associating all the PCC rules contained in the PCC rule table to the same QoS flow identity;

sequentially converting each PCC rule in the PCC rule table into an uplink service flow classification rule and a downlink service flow classification rule;

and sending all the downlink service flow classification rules to a user plane function, and sending all the uplink service data flow classification rules to the user terminal.

As can be seen from the above description, the session management network element 5 performs corresponding processing on the received PCC rule table according to the PCC session management policy, so that the flow classification rules in all PCC rules belonging to the same session can be processed and forwarded to the same user terminal.

The invention discloses a method and a system for issuing a PCC session management policy in a 5G system, which are suitable for an application scene of issuing the PCC session management policy in 5G communication, and are explained by combining specific embodiments as follows:

before this time, in order to better illustrate the contents of the solution of the present invention, some terms involved are explained as follows:

QoS: the network security mechanism is used for providing good service for network communication.

PCC: all referred to as policy control and charging, is a set of parameters + associated policy control and charging control parameters for one traffic data flow. The PCC rules provide rules on how the service data flows are classified and control rules on how policy and charging control is performed later. In the 5G system, the PCC rule is preconfigured by the PCF network element on the core network side or dynamically generated according to other trigger conditions.

In addition, the 3GPP protocol 2401 specifies that the number of packet filters included in a QoS Rule issued to the ue should be less than or equal to a preset number, and at present, the preset number is 15, so the following embodiment is exemplified by the preset number being 15.

Referring to fig. 1 to 3, a first embodiment of the present invention is;

a method for issuing PCC session management policy in a 5G system, as shown in fig. 1 and fig. 2, where AMF represents an access and mobility management function network element; PCF represents policy control network element 2; SMF stands for session management network element 5; UPF stands for user plane function; the method comprises the following steps:

in this embodiment, the policy control network element 2 initiates an update procedure of the PCC session management policy, and sends a policy management update notification to the session management network element 5, so as to notify the session management network element 5 that the PCC session management policy changes, and enable the session management network element 5 to process the PCC rule table according to the PCC session management policy corresponding to the PCC rule table. Before step S1, when the user terminal performs the protocol data unit session establishment procedure and interacts with the policy control network element 2 to obtain the protocol data unit session QoS policy, the session management network element 5 provides the policy management update notification address to the policy control network element 2, so that the policy control network element 2 sends the policy management update notification including the new PCC rule table and the PCC session management policy to the session management network element 5 when updating the PCC session management policy. The new PCC session management policy includes the following:

in this embodiment, it may be assumed that the number of packet filters that need to be mapped to the same QoS attribute is N, which is equal to the number of flow classification rules in the policy control network element 2, as shown in fig. 3, the policy control network element 2 determines whether the number of flow classification rules is greater than 15, that is, whether N is greater than 15, if yes, step S2 is performed, otherwise, a PCC rule is created according to the PCC rule configuration, the description information of each flow classification rule is added to the flow classification rule parameter of the PCC rule, and step S3 is performed. The description information of each flow classification rule includes information of a data packet detection component, such as information of a source IP address, a destination IP address, a protocol number, and the like of an IP data packet.

S2, if the number of the flow classification rules is greater than 15, the policy control network element 2 creates a plurality of PCC rules with the same PCC rule configuration except for different parameters of the flow classification rules, respectively adds the description information of the flow classification rules to the flow classification rule parameters of the plurality of PCC rules, and keeps the number of the flow classification rules identified by each PCC rule less than or equal to 15.

In this embodiment, the specific process of step S2 is:

s21, if the number of the flow classification rules is greater than 15, the policy control network element 2 divides all the flow classification rules into groups of flow classification rule groups in a grouping manner that 15 flow classification rules are grouped into one group and the remaining less than 15 flow classification rules are grouped into one group;

s22, the policy control network element 2 creates a PCC rule according to the PCC rule configuration, clones the PCC rule to obtain a plurality of PCC rules only with different flow classification rule parameters and the number equal to the number of flow classification rule packet groups, and sets an identification name for each PCC rule;

in this embodiment, except for the flow classification rule parameters of one PCC rule and its clone, the other parameters, such as the priority of the PCC rule, the associated QoSID, the associated gating policy, and the associated charging policy, are the same. And, the identification name of each PCC rule is also unique, if the identification name of the PCC rule of the ontology is pcrulea, the other clone PCC rules may be named pcrulea _ clone _1, pcrulea _ clone _2, pcrulea _ clone _3, and so on in sequence.

S23, the policy control network element 2 associates the flow classification rule groups with the PCC rules one by one, and adds the description information of all flow classification rules of each flow classification rule group to the flow classification rule parameters of the corresponding PCC rules.

S3, the policy control network element 2 adds all PCC rules to one PCC rule table, and sends the PCC rule table to the session management network element 5, so that the session management network element 5 completely issues all flow classification rules in the PCC rules to the user terminal.

In this embodiment, assuming that the number of the flow classification rules is 37, 1 to 15 flow classification rules are added to the pccreulea in one group, and then the pccreulea is added to the PCC rule table; adding the pccreuleA _ clone _1 into a group of 16-30, and then adding the pccreuleA _ clone _1 into a PCC rule table; the last 7 are also a group and added to pccrule a _ clone _2, after which pccrule a _ clone _2 is added to the PCC rule table.

In this embodiment, the PCC rules and the PCC rule table may be created in advance to cope with different PCC session management policies. After the addition is completed, the policy control network element 2 sends the PCC rule table and the QoS parameter to the session management network element 5 through the session management policy control service.

After receiving the policy management update notification including the new PCC rule table and the PCC session management policy, the session management network element 5 processes the PCC rule table according to the PCC session management policy corresponding to the PCC rule table, where the specific processing procedure is as follows:

firstly, a session management network element 5 receives a PCC rule table and associates all PCC rules contained in the PCC rule table to the same QoS Flow identity, namely, the same qfi (QoS Flow id);

in this embodiment, since the QoSID parameters associated with all PCC rules in the PCC rule table are the same. Thus, the session management network element 5 associates all PCC rules into the same QoS flow identity so that they have the same QoS treatment.

Then, the session management network element 5 sequentially converts each PCC rule in the PCC rule table into an uplink service flow classification rule and a downlink service flow classification rule;

in this embodiment, each PCC rule translates into one upstream traffic classification rule and one downstream traffic classification rule. That is, each upstream traffic classification rule also contains 15 packet filters, and each downstream traffic classification rule also contains 15 traffic data filters.

Finally, the session management network element 5 sends all the downlink traffic classification rules to the user plane function, and sends all the uplink traffic data classification rules to the user terminal.

In this embodiment, as shown in fig. 2, the session management network element 5 sends the downlink traffic classification rule carried in the session modification request message through a PFCP (packet filter control protocol) to the user plane function, and the user plane function receives and starts a new packet detection rule to perform service packet detection on the terminal. After the downlink traffic flow classification rule is updated, the session management network element 5 calls a Namf service provided by an AMF (access and mobility management function) network element, requests the AMF to forward N1 and N2 messages, issues a corresponding QoS rule to the user terminal, issues a QoS profile to the 5G base station, and modifies a corresponding session resource after the QoS profile is received by the wireless terminal side. At this point, the uplink and downlink QoS stream data of the user terminal are updated, and a new QoS strategy is executed.

Referring to fig. 4, a second embodiment of the present invention is:

a system 1 for issuing a PCC session management policy in a 5G system, as shown in fig. 4, includes a policy control network element 2 and a session management network element 5, where the policy control network element 2 includes a first memory 3, a first processor 4, and a computer program stored in the first memory 3 and operable on the first processor 4; the session management network element 5 comprises a second memory 6, a second processor 7 and a computer program stored on the second memory 6 and executable on the second processor 7.

The first processor 4 and the second processor 7 are jointly used to execute the method for issuing the PCC session management policy in the 5G system according to the first embodiment.

In summary, the present invention discloses a method and a system for issuing PCC session management policies in a 5G system, when the number of flow classification rules is larger than a preset number, for example, 15, that is, a packet filter that a session management network element needs to issue to a user terminal is larger than the preset number, a plurality of flow classification rule-only parameters are created, and other PCC rules with the same configuration are used to respectively encapsulate all flow classification rules, so that the number of flow classification rules of each PCC rule does not exceed the preset number, and further, the packet filters that the session management network element needs to normally process and issue each time are not larger than the preset number, which meets the specification in 3GPP protocol 2401, thereby ensuring that the session management network element can correctly and completely process.

The above description is only an embodiment of the present invention, and is not intended to limit the scope of the present invention, and all equivalent modifications made by the present invention and the contents of the accompanying drawings, which are directly or indirectly applied to the related technical fields, are included in the scope of the present invention.

Claims

1. A method for issuing PCC session management policy in a 5G system is characterized by comprising the following steps:

s1, the strategy control network element obtains the newest flow classification rule and the corresponding PCC rule configuration after the QoS strategy sent to the user terminal by the strategy control network element is changed;

2. The method according to claim 1, wherein the step S2 is specifically configured to:

s21, if the number of the flow classification rules is larger than the preset number, the strategy control network element divides all the flow classification rules into a plurality of groups of flow classification rule groups in a grouping mode that the preset number is one group and the rest is not more than the preset number and is also one group;

s22, the policy control network element creates one PCC rule according to the PCC rule configuration, clones the PCC rule to obtain a plurality of PCC rules, where only the flow classification rule parameters are different and the number of PCC rules is equal to the number of packet groups of the flow classification rule, and sets an identifier name for each PCC rule;

s23, the policy control network element associates the flow classification rule packet with the PCC rule one by one and adds the description information of all the flow classification rules of each flow classification rule packet to the flow classification rule parameters of the corresponding PCC rule.

3. The method according to claim 1, wherein the step S3 further includes:

and the policy control network element sends a policy management update notification to the session management network element so as to notify the session management network element that a PCC session management policy changes and enable the session management network element to process the PCC rule table according to the PCC session management policy corresponding to the PCC rule table.

4. The method of claim 1, wherein the step between S1 and S2 further comprises:

the policy control network element determines whether the number of the flow classification rules is greater than a preset number, if so, the step S2 is executed, otherwise, one PCC rule is created according to the PCC rule configuration, the description information of each flow classification rule is added to the flow classification rule parameters of the PCC rule, and the step S3 is executed.

5. The method according to claim 3, wherein the processing, by the session management network element according to the PCC session management policy corresponding to the PCC rule table, of the PCC session management policy issue specifically includes:

the session management network element receives the PCC rule table and associates all the PCC rules contained in the PCC rule table with the same QoS flow identity;

the session management network element converts each PCC rule in the PCC rule table into an uplink service flow classification rule and a downlink service flow classification rule in sequence;

and the session management network element sends all the downlink service flow classification rules to a user plane function and sends all the uplink service data flow classification rules to the user terminal.

6. A system for issuing a PCC session management policy in a 5G system, comprising a policy control network element and a session management network element, where the policy control network element includes a first memory, a first processor, and a computer program stored in the first memory and operable on the first processor, and when the computer program is executed by the first processor, the following steps are implemented:

s2, if the number of the flow classification rules is greater than a preset number, creating a plurality of PCC rules having the same PCC rule configuration except for different parameters of the flow classification rules, respectively adding description information of the plurality of flow classification rules to the parameters of the flow classification rules of the plurality of PCC rules, and keeping the number of the flow classification rules identified by each PCC rule less than or equal to the preset number, where the preset number is the single maximum throughput in a session management network element;

7. The system according to claim 6, wherein the step S2 specifically is:

8. The system according to claim 6, wherein the step S3 further includes:

sending a policy management update notification to the session management network element to notify the session management network element that a PCC session management policy changes and enable the session management network element to process the PCC rule table according to the PCC session management policy corresponding to the PCC rule table.

9. The system according to claim 6, wherein between the step S1 and the step S2, the system for issuing the PCC session management policy in the 5G system further comprises:

10. The system according to claim 6, wherein the session management network element comprises a second memory, a second processor, and a computer program stored in the second memory and executable on the second processor, and when the computer program is executed by the second processor, the method implements the following steps: