CN111328123B

CN111328123B - Method and device for releasing network segment

Info

Publication number: CN111328123B
Application number: CN201811533487.4A
Authority: CN
Inventors: 龙思锐; 屈琴
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-12-14
Filing date: 2018-12-14
Publication date: 2022-06-24
Anticipated expiration: 2038-12-14
Also published as: CN111328123A; WO2020119791A1

Abstract

The application provides a method and a device for releasing network segments, relates to the technical field of communication, and is used for solving the problem that different PGW-Us release the same network segment route under the condition that Sxb interface links between the PGW-C and the PGW-U are flashed. The method comprises the following steps: when the control plane gateway determines that no session uses the address in the first network segment, the control plane gateway sends a first message for indicating the data plane gateway to release the first network segment to the data plane gateway occupying the first network segment, and the control plane gateway receives a second message for indicating the data plane gateway to release the first network segment from the data plane gateway and releases the first network segment according to the second message. The control plane gateway releases the first network segment after the data plane gateway releases the first network segment, so that the first network segment cannot be allocated to the two data plane gateways, and the two data plane gateways are prevented from issuing the same network segment route.

Description

Method and device for releasing network segment

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method and an apparatus for releasing a network segment.

Background

In an Evolved Packet System (EPS) network in which a Control Plane (CP) and a User Plane (UP) are separated, during activation of a session, a packet data network control plane function (PGW-C) allocates an Internet Protocol (IP) address to the session.

A route of downlink data from an IP server (Operator's IP Servers) of an Operator to a user is published by a packet data gateway user plane function (PGW-U for short), and in order to avoid a problem of an excessive number of routes in a network caused by the PGW-U publishing a path (i.e., a host route) for each session, the PGW-U publishes a segment route when actually publishing a route. When two PGW-us issue the same segment route, the Operator's IP Servers may send service data through any one of the two PGW-us, and users served by the two PGW-us are different users, so that the users may not receive the service data. To avoid this problem, it is necessary to ensure that sessions using addresses in the same network segment are active on the same PGW-U. And when all addresses in a network segment are not used by the session, the PGW-C and the PGW-U both need to release the network segment.

Under the condition that a Sxb interface link between the PGW-C and the PGW-U1 is flashed, during the deactivation process of the session 1, a Packet Forwarding Control Protocol (PFCP) session deletion request (PFCP session deletion request) message sent by the PGW-C to the PGW-U1 and used for the PGW-U1 to delete the session 1 may not reach the PGW-U1. Then session 1 is deleted in PGW-C and session resources for session 1 are still reserved in PGW-U1. When the last session on PGW-C using the address in segment 1 (the segment to which the IP address of session 1 belongs) is deactivated, PGW-C releases segment 1 and may assign segment 1 to PGW-U2, whereas PGW-U1 does not release segment 1 because it is assumed that session 1 is still using the address in segment 1. At this time, PGW-U1 and PGW-U2 may issue the same network segment route, so that the user may not receive the traffic data.

Disclosure of Invention

The embodiment of the application provides a method and a device for releasing network segments, which are used for solving the problem that different PGW-Us issue the same network segment route under the condition that Sxb interface links between the PGW-C and the PGW-U are flashed.

In order to achieve the above object, the embodiments of the present application provide the following technical solutions:

in a first aspect, a method for releasing a network segment is provided, which includes: when the control plane gateway determines that no session uses the address in the first network segment, the control plane gateway sends a first message for indicating the data plane gateway to release the first network segment to the data plane gateway occupying the first network segment, and the control plane gateway receives a second message for indicating the data plane gateway to release the first network segment from the data plane gateway and releases the first network segment according to the second message. In the method provided by the first aspect, the control plane gateway releases the first network segment after the data plane gateway releases the first network segment, so that the first network segment is not allocated to the two data plane gateways, and the two data plane gateways are prevented from issuing the same network segment route.

In a second aspect, a method for releasing a network segment is provided, which includes: the data plane gateway receives a first message from the control plane gateway and releases a first network segment according to the first message, wherein the first message is used for indicating the data plane gateway to release the first network segment; and the data plane gateway sends a second message to the control plane gateway, wherein the second message is used for indicating the data plane gateway to release the first network segment. In the method provided by the second aspect, the control plane gateway releases the first network segment after the data plane gateway releases the first network segment, so that the first network segment is not allocated to the two data plane gateways, and the two data plane gateways are prevented from issuing the same network segment route.

In a third aspect, a method for releasing a network segment is provided, including: when the control plane gateway determines that no session uses an address in the first network segment, the control plane gateway sends a first message to a data plane gateway occupying the first network segment, wherein the first message is used for indicating the data plane gateway to release the first network segment; if the control plane gateway does not receive the response message of the first message, the control plane gateway sends the first message to the data plane gateway at intervals, and if the control plane gateway does not receive the response message of the first message within a first preset time period, the control plane gateway releases the network segment distributed to the data plane gateway; the starting time of the first preset time period is the time for the control plane gateway to send the first message, or the starting time of the first preset time period is the time for the control plane gateway to determine the interruption of an interface link between the control plane gateway and the data plane gateway; the data plane gateway determines that an interface link between the data plane gateway and the control plane gateway is interrupted; and the data plane gateway releases the network segment distributed by the control plane gateway in the data plane gateway after a second preset time period, wherein the second preset time period is less than the first preset time period. In the method provided in the third aspect, since the first preset time period is longer than the second preset time period, after the data plane gateway releases the network segment allocated to the control plane gateway in the data plane gateway, the network segment allocated to the data plane gateway in the control plane gateway is released, so that the same network segment cannot be allocated to two data plane gateways, and the two data plane gateways are prevented from issuing the same network segment route.

In a fourth aspect, a method for releasing a network segment is provided, which includes: the data plane gateway checks the network segment with the control plane gateway to determine the invalid network segment of the data plane gateway and releases the invalid network segment of the data plane gateway; the invalid network segment of the data plane gateway refers to a network segment, except all network segments which are recorded on the control plane gateway and are already allocated to the data plane gateway, of all network segments allocated by the control plane gateway in the data plane gateway. In the method provided in the fourth aspect, by releasing the invalid network segment of the data plane gateway, the data plane gateway and the data plane gateway occupying the invalid network segment of the data plane gateway can be prevented from issuing the same network segment route.

In a fifth aspect, a method for releasing a network segment is provided, which includes: the control plane gateway sends at least one checking request to the data plane gateway, wherein the at least one checking request comprises information of all network segments distributed to the data plane gateway and recorded on the control plane gateway. In the method provided by the fifth aspect, the control plane gateway sends the verification request to the data plane gateway, so that the data plane gateway can perform network segment verification.

In a sixth aspect, a method for releasing a network segment is provided, which includes: the control plane gateway receives at least one check request from the data plane gateway, wherein the at least one check request comprises information of all network segments distributed by the control plane gateway in the data plane gateway; the control plane gateway judges whether each network segment in all network segments distributed by the control plane gateway in the data plane gateway records on the control plane gateway and is distributed to the data plane gateway or not according to at least one check request; the control plane gateway sends at least one check response to the data plane gateway, wherein the at least one check response comprises information whether each network segment in all network segments distributed by the control plane gateway in the data plane gateway records the information distributed to the data plane gateway on the control plane gateway. In the method provided by the sixth aspect, the control plane gateway sends a verification response to the data plane gateway according to the verification request, so that the data plane gateway can perform network segment verification.

In a seventh aspect, a method for releasing a network segment is provided, including: the first data plane gateway determines that the control plane gateway is reset and restarted; and the first data plane gateway releases the network segment distributed to the first data plane gateway before the control plane gateway is reset and restarted. In the method provided by the seventh aspect, the first data plane gateway releases the network segment first and then deletes the session, and the release of the network segment does not depend on the deletion of the session, thereby ensuring the rapid recovery of the network segment.

In an eighth aspect, a method for releasing a network segment is provided, which includes: when the control plane gateway is reset and restarted, the control plane gateway refuses the activation of a new session; the control plane gateway receives a third message and/or at least one fourth message sent by all data plane gateways connected with the control plane gateway; a third message sent by a data plane gateway is used for indicating the data plane gateway to release the network segment allocated to the data plane gateway before the control plane gateway is reset and restarted, and at least one fourth message sent by the data plane gateway comprises the information of the network segment allocated to the data plane gateway before the control plane gateway in the data plane gateway is reset and restarted; the control plane gateway allows new session activation. In the method provided by the eighth aspect, after the reset and restart, the control plane gateway does not know which network segments are occupied by which data plane gateways, so the control plane gateway can refuse to activate a new session, and if a session activation request is received, the control plane gateway can return a response message of activation failure, thereby preventing the same network segment from being allocated to different data plane gateways.

In a ninth aspect, there is provided a communication apparatus comprising: a communication unit and a processing unit; the processing unit is used for determining the address in the first network segment without session use; the communication unit is configured to send a first message to a data plane gateway, where the first message is used to instruct the data plane gateway to release the first network segment, and the data plane gateway is a data plane gateway occupying the first network segment; the communication unit is further configured to receive a second message from the data plane gateway, where the second message is used to indicate that the data plane gateway releases the first network segment; the processing unit is further configured to release the first network segment according to the second message. In the communication device according to the ninth aspect, the first network segment is released after the data plane gateway releases the first network segment, so that the first network segment is not allocated to two data plane gateways, and the two data plane gateways are prevented from issuing the same network segment route. The communication device may be a control plane gateway.

In a possible implementation manner, the processing unit is specifically configured to: when the communication device receives a deactivation request for a first session, it determines whether the first session is the last session using an address in the first network segment and, if so, determines that no sessions use an address in the first network segment. In one possible implementation, a method is provided for the communication device to determine that no session uses an address in a first network segment.

In one possible implementation manner, the first message includes a first timestamp, and the first timestamp is used for indicating a time when the communication apparatus transmits the first message. According to the possible implementation mode, the communication device can release the first network segment when the time stamp of the local session is earlier than the first time stamp according to the first time stamp, otherwise, the first network segment is not released, so that the mistaken deletion of the session and the mistaken release of the network segment are prevented.

In a tenth aspect, there is provided a communication apparatus comprising: a communication unit and a processing unit; the communication unit is configured to receive a first message from a control plane gateway, where the first message is used to instruct the communication device to release the first network segment; the processing unit is used for releasing the first network segment according to the first message; the communication unit is further configured to send a second message to the control plane gateway, where the second message is used to indicate that the communication device releases the first network segment. In the communication device provided by the tenth aspect, the sent second message may be used by the control plane gateway to determine that the communication device releases the first network segment, so that the control plane gateway releases the first network segment after the communication device releases the first network segment, and thus the first network segment is not allocated to two communication devices, and the two communication devices are prevented from issuing the same network segment route. The communication device may be a data plane gateway.

In a possible implementation manner, the processing unit is further configured to delete a local session using an address in the first network segment. This possible implementation may substantially free up resources (e.g., storage resources) of the communication device.

In a possible implementation manner, the first message includes a first timestamp, where the first timestamp is used to indicate a time when the control plane gateway sends the first message, and the processing unit is specifically configured to: judging whether a local session using the address in the first network segment exists according to the first message; if yes, comparing the time stamp for creating the local session with the first time stamp; and if the time stamp for creating the local session is earlier than the first time stamp, releasing the first network segment. According to the possible implementation mode, the communication device can release the first network segment when the time stamp of the local session is earlier than the first time stamp according to the first time stamp, otherwise, the first network segment is not released, so that the mistaken deletion of the session and the mistaken release of the network segment are prevented.

In an eleventh aspect, a communication apparatus is provided, including: a first module and a second module; the first module comprises a first communication unit and a first processing unit; the second module comprises a second processing unit; the first processing unit is used for determining an address in a first network segment used without a session; the first communication unit is configured to send a first message to a second module, where the first message is used to instruct the second module to release the first network segment, and the second module is a second module occupying the first network segment; the first communication unit is further configured to send the first message to the second module at intervals when a response message of the first message is not received; the first processing unit is further configured to release the network segment allocated to the second module when no response message of the first message is received within a first preset time period; the starting time of the first preset time period is the time when the first module sends the first message, or the starting time of the first preset time period is the time when the first module determines that the interface link between the first module and the second module is interrupted; the second processing unit is used for determining the interruption of an interface link with the first module; the second processing unit is further configured to release the network segment allocated by the first module in the second module after a second preset time period, where the second preset time period is shorter than the first preset time period. In the communication device provided in the eleventh aspect, since the first preset time period is longer than the second preset time period, after the second module releases the network segment allocated to the first module in the second module, the network segment allocated to the second module in the first module is released, so that the same network segment cannot be allocated to two second modules, and the two second modules are prevented from issuing the same network segment route. The first module may be a control plane gateway and the second module may be a data plane gateway.

In a possible implementation manner, the second processing unit is further configured to delete a local session using an address in a network segment allocated by the first module. This possible implementation may substantially free resources (e.g., storage resources) of the second module.

In a twelfth aspect, a communication apparatus is provided, including: a communication unit and a processing unit; the processing unit is used for utilizing the communication unit and the control plane gateway to carry out network segment check to determine an invalid network segment of the communication device; the invalid network segment of the communication device refers to a network segment which is recorded on the control plane gateway and is allocated to the communication device, in all network segments allocated by the control plane gateway in the communication device; the processing unit is further configured to release an invalid network segment of the communication device. In the communication device according to the twelfth aspect, by releasing the invalid network segment of the communication device, the communication device and the communication device occupying the invalid network segment of the communication device can be prevented from issuing the same network segment route. The communication device may be a data plane gateway.

In one possible implementation, the processing unit is further configured to delete a local session using an address in an invalid network segment of the communication device. This possible implementation may substantially free up resources (e.g., storage resources) of the communication device.

In a possible implementation manner, the processing unit is specifically configured to: receiving, by the communication unit, at least one check request from the control plane gateway, the at least one check request including information of all network segments allocated to the communication device recorded on the control plane gateway; marking network segments which belong to all network segments distributed to the communication device and recorded on the control plane gateway in all network segments distributed to the communication device in the communication device according to the at least one checking request; and determining unmarked network segments of all network segments distributed by the control plane gateway in the communication device as invalid network segments of the communication device. The possible implementation mode provides a network segment checking method.

In a possible implementation manner, the processing unit is specifically configured to: sending at least one check request to the control plane gateway by using the communication unit, wherein the at least one check request comprises information of all network segments distributed by the control plane gateway in the communication device; receiving, by the communication unit, at least one check response from the control plane gateway, the at least one check response including information on whether each of all network segments allocated by the control plane gateway in the communication device records information on the control plane gateway that has been allocated to the communication device; and according to the at least one checking response, determining the network segment which is distributed to the communication device and recorded on the control plane gateway from all the network segments distributed by the control plane gateway in the communication device as an invalid network segment of the communication device. The possible implementation mode provides another network segment checking method.

In a possible implementation manner, if the at least one checking request is a plurality of checking requests, a last checking request in the plurality of checking requests includes an end flag bit, where the end flag bit is used to indicate that the checking request to which the terminal belongs is the last checking request. This possible implementation manner may enable the communication device (or control plane gateway) to determine the initial checking request and the end checking request, thereby determining whether the control plane gateway (or communication device) finishes sending the information of the segment that needs to be sent.

In a thirteenth aspect, a communication apparatus is provided, including: a communication unit and a processing unit; the processing unit is configured to send at least one checking request to a data plane gateway through the communication unit, where the at least one checking request includes information of all network segments allocated to the data plane gateway recorded on the communication device. The communication device according to the thirteenth aspect may enable the data plane gateway to perform network segment verification by sending a verification request to the data plane gateway. The communication device may be a control plane gateway.

In a fourteenth aspect, a communication apparatus is provided, including: a communication unit and a processing unit; the communication unit is used for receiving at least one checking request from a data plane gateway, wherein the at least one checking request comprises information of all network segments distributed by the communication device in the data plane gateway; the processing unit is configured to determine, according to the at least one check request, whether each of all network segments allocated by the communication device in the data plane gateway records, on the communication device, that the network segment has been allocated to the data plane gateway; the communication unit is further configured to send at least one check response to the data plane gateway, where the at least one check response includes whether each of all network segments allocated by the communication device in the data plane gateway records information allocated to the data plane gateway on the communication device. In the communication apparatus provided in the fourteenth aspect, the communication apparatus sends a verification response to the data plane gateway according to the verification request, so that the data plane gateway can perform network segment verification. The communication device may be a control plane gateway.

In a fifteenth aspect, a communication device is provided, comprising: a processing unit; and the processing unit is used for determining the reset restart of the control plane gateway and releasing the network segment distributed to the communication device before the reset restart of the control plane gateway. In the communication device provided by the fifteenth aspect, the network segment is released first, and then the session is deleted, and the release of the network segment does not depend on the deletion of the session, so that the rapid recovery of the network segment is ensured. The communication device may be a first data plane gateway.

In one possible implementation, the communication apparatus further includes: a communication unit; the communication unit is configured to send a third message to the control plane gateway, where the third message is used to indicate that the communication device has released the network segment allocated to the communication device before the control plane gateway is reset and restarted. The possible implementation mode can ensure that the control plane gateway determines that the network segment distributed on the communication device before the control plane gateway is reset and restarted is released, so that the control plane gateway unlocks the network segment.

In a possible implementation manner, the processing unit is further configured to delete a local session using an address in a network segment allocated to the communication device before the control plane gateway reset restart. This possible implementation may substantially free up resources (e.g., storage resources) of the communication device.

In a possible implementation manner, the communication unit is further configured to send at least one fourth message to the control plane gateway, where the at least one fourth message includes information of a network segment of the communication device.

In a possible implementation manner, a last fourth message in the at least one fourth message includes an end flag bit, where the end flag bit is used to indicate that the fourth message is a last fourth message.

In a sixteenth aspect, a communication apparatus is provided, including: a processing unit and a communication unit; the processing unit is used for refusing the activation of a new session when the communication device is reset and restarted; the communication unit is used for receiving a third message and/or at least one fourth message sent by all data plane gateways connected with the communication device; a third message sent by a data plane gateway is used for indicating the data plane gateway to release the network segment allocated to the data plane gateway before the communication device is reset and restarted, and at least one fourth message sent by the data plane gateway comprises the information of the network segment allocated to the data plane gateway before the communication device in the data plane gateway is reset and restarted; the processing unit is further configured to allow a new session to be activated. The communication device according to the sixteenth aspect may reject new session activation because after the reset restart, the communication device does not know which network segments are occupied by which data plane gateways, and if a session activation request is received, the communication device may return a response message indicating that activation has failed, thereby preventing the same network segment from being assigned to a different data plane gateway. The communication device may be a control plane gateway.

In a possible implementation manner, in a case where the communication device receives only at least one fourth message sent by all data plane gateways connected to the communication device, the processing unit is further configured to allocate, for a newly activated session, an address in a network segment other than a network segment allocated before the communication device in all data plane gateways resets and restarts. In this possible implementation manner, after the communication device receives at least one fourth message sent by all data plane gateways connected to the communication device, the communication device knows which network segments are occupied by which data plane gateways, so that the communication device can allow a new session to be activated, but the address allocated to the newly activated session should not reset the address allocated to the network segment before restarting for the communication device in all data plane gateways, thereby preventing the same network segment from being allocated to a different data plane gateway.

In a possible implementation manner, in a case that the communication device receives only at least one fourth message sent by all data plane gateways connected to the communication device, the processing unit is further configured to lock a network segment allocated before the communication device in all data plane gateways resets and restarts; the communication unit is further used for receiving a third message from the first data plane gateway; the processing unit is further configured to unlock the network segment allocated to the first data plane gateway before the communication device is reset and restarted. According to the possible implementation mode, the communication device locks the network segments of the data plane gateways, so that the communication device can be prevented from allocating the network segments to other data plane gateways before the PGW-U releases the network segments, and the two data plane gateways are prevented from issuing the same network segment route.

In a seventeenth aspect, a communication device is provided, comprising: a memory, a processor, at least one communication interface, and a communication bus; the memory is used for storing computer-executable instructions, the processor, the memory and the at least one communication interface are connected through a communication bus, and the processor executes the computer-executable instructions stored in the memory to enable the communication device to realize any one of the methods provided by the first aspect; alternatively, the control plane gateway in any one of the methods provided in the third aspect performs the method; alternatively, the method provided in the fifth aspect; alternatively, the method provided in the sixth aspect; alternatively, the eighth aspect provides any one of the methods. The communication device may be in the form of a chip product.

In an eighteenth aspect, there is provided a communication apparatus comprising: a memory, a processor, at least one communication interface, and a communication bus; the memory is used for storing computer-executable instructions, the processor, the memory and the at least one communication interface are connected through a communication bus, and the processor executes the computer-executable instructions stored by the memory to enable the communication device to realize any one of the methods provided by the second aspect; alternatively, the method performed by the data plane gateway in any one of the methods provided in the third aspect; alternatively, any one of the methods provided in the fourth aspect; alternatively, any one of the methods provided in the seventh aspect. The communication device may be in the form of a chip product.

In a nineteenth aspect, there is provided a computer-readable storage medium comprising instructions which, when executed on a computer, cause the computer to perform any one of the methods provided in the first aspect; alternatively, the control plane gateway in any one of the methods provided in the third aspect performs the method; alternatively, the method provided in the fifth aspect; alternatively, the method provided in the sixth aspect; alternatively, the eighth aspect provides any one of the methods.

In a twentieth aspect, there is provided a computer-readable storage medium comprising instructions which, when executed on a computer, cause the computer to perform any one of the methods provided by the second aspect; alternatively, the method performed by the data plane gateway in any one of the methods provided in the third aspect; alternatively, any one of the methods provided in the fourth aspect; alternatively, any one of the methods provided in the seventh aspect. The communication device may be in the form of a chip product.

In a twenty-first aspect, there is provided a computer program product comprising instructions which, when run on a computer, cause the computer to perform any one of the methods provided in the first aspect; alternatively, the control plane gateway in any one of the methods provided in the third aspect performs the method; alternatively, the method provided by the fifth aspect; alternatively, the method provided in the sixth aspect; alternatively, the eighth aspect provides any one of the methods.

In a twenty-second aspect, there is provided a computer program product containing instructions which, when run on a computer, cause the computer to perform any one of the methods provided by the second aspect; alternatively, the method performed by the data plane gateway in any one of the methods provided in the third aspect; alternatively, any one of the methods provided by the fourth aspect; alternatively, the seventh aspect provides any one of the methods. The communication device may be in the form of a chip product.

In a twenty-third aspect, there is provided a communication system comprising: the control plane gateway in the first aspect and the data plane gateway in the second aspect; or, the control plane gateway and the data plane gateway in the third aspect; or, the data plane gateway in the fourth aspect and the control plane gateway in the fifth aspect (or the sixth aspect); the control plane gateway of the eighth aspect and the first data plane gateway of the seventh aspect.

It should be noted that, all possible implementation manners of any one of the above aspects may be combined without departing from the scope of the claims.

Drawings

Fig. 1 is a schematic architecture diagram of an EPS network according to an embodiment of the present application;

fig. 2 is a schematic hardware structure diagram of a communication device according to an embodiment of the present disclosure;

fig. 3 to fig. 5 are flowcharts of a method for releasing a network segment according to an embodiment of the present application, respectively;

fig. 6 is a schematic composition diagram of a communication device according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Where in the description of the present application, "/" indicates an OR meaning, for example, A/B may indicate A or B, unless otherwise indicated. "and/or" herein is merely an association relationship describing an associated object, and means that there may be three relationships, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone. Also, in the description of the present application, "a plurality" means two or more than two unless otherwise specified. In addition, in order to facilitate clear description of technical solutions of the embodiments of the present application, in the embodiments of the present application, terms such as "first" and "second" are used to distinguish the same items or similar items having substantially the same functions and actions. Those skilled in the art will appreciate that the terms "first," "second," etc. do not denote any order or quantity, nor do the terms "first," "second," etc. denote any order or importance.

The technical scheme of the embodiment of the application can be applied to various data processing communication systems. For example: orthogonal Frequency Division Multiple Access (OFDMA), single carrier frequency division multiple access (SC-FDMA), and other systems. The term "system" may be used interchangeably with "network". The OFDMA system may implement a radio technology such as evolved universal radio terrestrial access (evolved UTRA, abbreviated as E-UTRA), Ultra Mobile Broadband (UMB), and the like. E-UTRA is an evolved version of the Universal Mobile Telecommunications System (UMTS). The third generation partnership project (3rd generation partnership project, 3GPP) is using a new version of E-UTRA in Long Term Evolution (LTE) and various versions based on LTE evolution. The fifth generation (5th-generation, abbreviated as 5G) communication system and the New Radio (NR) are the next generation communication systems under study. In addition, the communication system can also be applied to future-oriented communication technologies, and the technical solutions provided by the embodiments of the present application are all applied.

As shown in fig. 1, an EPS network may include a plurality of functional network elements: a terminal, an evolved universal terrestrial radio access network (E-UTRAN) (specifically, eNodeB), a Serving Gateway (SGW), a packet data network (PGW), a Mobility Management Element (MME), a Home Subscriber Server (HSS), a Mobile Switching Center (MSC), and a Policy and Charging Rules Function (PCRF) network element.

The architecture of separating CP and UP is defined in the 3rd generation partnership project (3 GPP) standard. Under the architecture, PGW is split into PGW-C and PGW-U, and SGW is split into SGW-C and SGW-U. The PGW-U and the SGW-U are user plane functional elements and are responsible for forwarding user data. One PGW-C may correspond to one or more PGW-U, and one SGW-C may correspond to one or more SGW-U. The interface between the PGW-C and the PGW-U is an Sxb interface, and the interface between the SGW-C and the SGW-U is a Sxa interface.

A user may access the network using multiple sessions, each session requiring an IP address. Therefore, during a session activation, the PGW-C or an external server (e.g., Authentication, Authorization, Accounting, AAA, Dynamic Host Configuration Protocol (DHCP) server) may allocate an IP address for the session, the IP address of the session is sent to the PGW-U by the PGW-C, and the PGW-U issues a route (i.e., host route) for downstream data from operators' IP Servers to the user.

If the PGW-U issues one host route for each session, the number of routes issued in the network is too large. Therefore, the PGW-C informs the PGW-U of the IP address of the session and also informs the network segment (also called address segment or address sub-segment, which indicates a continuous address) to which the IP address of the session belongs. And the PGW-U releases the network segment routes according to the network segments informed by the PGW-C so as to reduce the number of the routes released in the network.

When two PGW-us publish the same segment route, the user may not receive the traffic data. To avoid this problem, it is necessary to ensure that sessions using addresses in the same network segment are active on the same PGW-U. For example, during the first session activation using the address in segment 1, PGW-C assigns the first address in segment 1 to the session, and if the session is selected to be activated on PGW-U1, it will also mark segment 1 as being PGW-U1 (i.e., segment 1 is assigned to PGW-U1). When further sessions are subsequently active, addresses in segment 1 can only be assigned to the sessions active on the PGW-U1.

When all addresses in a network segment are not used for a session, both the PGW-C and the PGW-U need to release the network segment. For the PGW-U, if the deactivated session is the last session using the address in a certain network segment, the PGW-U deletes the network segment route of the network segment, thereby releasing the network segment. For the PGW-C, if the deactivated session is the last session using the address in a certain segment, after sending a PFCP session termination request message to the PGW-U to delete the last session, the PGW-C will clear the information that the segment was previously recorded and allocated to the PGW-U, and when other subsequent sessions are activated, the PGW-C may allocate the address in the segment to the other sessions, and the other sessions may be activated on any PGW-U.

The above manners for releasing the network segment by the PGW-C and the PGW-U have disadvantages in some scenarios, which are described below.

Sxb interface link flash between scenario 1, PGW-C, and PGW-U1

In this scenario, in the deactivation process of session 1, a PFCP session deletion request (PFCP session deletion request) message sent by the PGW-C to the PGW-U1 and used for the PGW-U1 to delete session 1 may not reach the PGW-U1. Then, session 1 is deleted in PGW-C, and session resources for session 1 are still reserved in PGW-U1. When the last session on PGW-C using the address in segment 1 (the segment to which the IP address of session 1 belongs) is deactivated, PGW-C releases segment 1 and may assign segment 1 to PGW-U2, whereas PGW-U1 does not release segment 1 because it is assumed that session 1 is still using the address in segment 1. At this time, PGW-U1 and PGW-U2 may issue the same network segment route, so that the user may not receive the traffic data.

Sxb interface link outages between scenario 2, PGW-C, and PGW-U1

In this scenario, after sensing that a Sxb interface link between the PGW-U1 and the PGW-C is faulty, the PGW-U1 initiates batch deletion of sessions, and in the process of batch deletion of sessions, when a session is the last session using an address in a network segment, the PGW-U1 also releases the network segment. However, to avoid false positives, the PGW-U1 perceives that it takes some time between the Sxb interface link failure with the PGW-C and the decision to initiate bulk deletion of sessions. The PGW-U1 also takes some time to complete the bulk deletion of the session. During these two periods, the PGW-C will release a segment if the last session using an address in that segment is deactivated. If the PGW-C allocates the network segment to the PGW-U2 in these two periods of time, the PGW-U1 and the PGW-U2 may issue the same network segment route, so that the user may not receive the service data.

Scene 3, PGW-C reset restart

In this scenario, the PGW-C may lose the allocation of the IP address of the session and the allocation of the network segment. When a subsequent session is activated, the PGW-C may not allocate an IP address to the session according to the allocation condition of the previous network segment, and an address in the network segment previously allocated to the PGW-U1 may be allocated to the session activated on the PGW-U2, so that different PGW-us may issue the same network segment route, and thus, the user may not receive service data.

It should be noted that although the PGW-U1 initiates bulk deletion of sessions after sensing the PGW-C reset restart, in the bulk deletion of sessions, when a session is the last session using an address in a network segment, the PGW-U1 also releases the network segment. However, the PGW-U1 needs a period of time for completing the bulk deletion of the session, during which the user's traffic is likely to be affected.

In order to solve these disadvantages, embodiments of the present application provide a communication device, which may specifically be a control plane gateway or a data plane gateway in the following. Hardware structure diagram of communication device referring to fig. 2, fig. 2 shows a hardware structure diagram of a communication device 20, which includes at least one processor 201, a communication bus 202 and at least one communication interface 204. Optionally, the communication device 20 further comprises a memory 203.

The processor 201 may be a general processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more ics for controlling the execution of programs according to the present disclosure.

The communication bus 202, which may include a path, carries information between the aforementioned components.

The communication interface 204, which may be any transceiver or the like, is used to communicate with other devices or communication networks.

The memory 203 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a Random Access Memory (RAM) or other types of dynamic storage devices that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited to such. The memory may be self-contained and coupled to the processor via a bus. The memory may also be integral to the processor.

The memory 203 is used for storing application program codes for executing the scheme of the application, and the processor 201 controls the execution. The processor 201 is configured to execute the application program code stored in the memory 203, thereby implementing the method provided by the embodiment of the present application.

In particular implementations, processor 201 may include one or more CPUs such as CPU0 and CPU1 in fig. 2, for example, as one embodiment.

In particular implementations, communication device 20 may include multiple processors, such as processor 201 and processor 208 in fig. 2, for example, as an example. Each of these processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, and/or processing cores for processing data (e.g., computer program instructions).

In one embodiment, the communication apparatus 20 may further include an output device 205 and an input device 206.

The system architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not constitute a limitation on the technical solution provided in the embodiment of the present application. As can be known to those skilled in the art, with the evolution of network architecture and the emergence of new service scenarios, the technical solution provided in the embodiments of the present application is also applicable to similar technical problems. For convenience of description, the method provided by the embodiment of the present application is exemplarily illustrated below by taking the method provided by the embodiment of the present application as an example when being applied to an EPS network. The control plane gateway in the embodiment of the present application is hereinafter referred to as a PGW-C (that is, the PGW-C may be replaced by a control plane gateway hereinafter), and the data plane gateway is referred to as a PGW-U (that is, the PGW-U may be replaced by a data plane gateway hereinafter).

However, it should be noted that the method provided in the embodiment of the present application may also be applied to other networks, for example, may be applied to an NR system or a 5G network. Accordingly, when the method provided by the embodiment of the present application is applied to an NR system or a 5G network, a network node that executes the method provided by the embodiment of the present application may be replaced with a network node in the NR system or the 5G network. For example, when the method provided in the embodiment of the present application is applied to an EPS network, the control plane gateway in the embodiment of the present application may be a PGW-C, and the data plane gateway may be a PGW-U. When the method provided in this embodiment of the present application is applied to an NR system or a 5G network, a control plane gateway in this embodiment of the present application may be a Session Management Function (SMF) network element, and a data plane gateway may be a User Plane Function (UPF) network element. Correspondingly, the Sxb interface link is replaced by an interface link between the SMF and the UPF.

It should be noted that the terms or expressions used in the embodiments of the present application may be mutually referred to, and are not limited. In the embodiment of the present application, "releasing network segment a" may also be described as "deleting the route of network segment a," and network segment a may be any network segment released in the following.

Example one

The embodiment provides a method for releasing a network segment, as shown in fig. 3, including:

301. the PGW-C determines that no session uses the address in the first network segment.

The first network segment can be any network segment allocated to the PGW-U by the PGW-C.

When the step 301 is implemented specifically, it may be implemented in one or two of the following ways:

in a first manner, after the PGW-C sends a message indicating deletion of the last local session using the address in the first network segment to the PGW-U, the PGW-C may determine that no session uses the address in the first network segment.

And secondly, when the PGW-C receives a deactivation request of the first session, the PGW-C determines whether the first session is the last session using the address in the first network segment, and if so, the PGW-C determines that no session uses the address in the first network segment. The first session may be any one of the sessions.

302. And the PGW-C sends a first message to the PGW-U, wherein the first message is used for indicating the PGW-U to release the first network segment, and the PGW-U occupies the first network segment.

The first message may include information used for indicating the first network segment, for example, the information of the first network segment may be an IP address and a mask of the first network segment, and the information of the first network segment may also be a start IP address and an end IP address of the first network segment. The information of the network segment in the second embodiment and the third embodiment described below may also be the IP address and the mask of the network segment, or may also be the start IP address and the end IP address of the network segment, which is not described in detail below.

Further, the first message may further include information for instructing the PGW-U to release the network segment, and of course, the information may also be indicated by a message type of the first message.

The first message may be a node-level message (e.g., a PFCP association update request) or a session-level message (e.g., a PFCP session deletion request). Whether the first message is a node-level message or a session-level message, the PGW-U may be instructed to release the first network segment by adding a private information element containing information of the first network segment to the first message. The first message may also be a newly defined message instead of an existing message, which is not specifically limited in this embodiment of the present application.

In one case (denoted case 1), the PGW-U successfully receives the first message, in which case steps 303a-305a may be performed after step 302.

303a, the PGW-U receiving the first message from the PGW-C and releasing the first network segment according to the first message.

Optionally, the first message further includes a first timestamp, where the first timestamp is used to indicate a time when the PGW-C sends the first message. In this case, the releasing, by the PGW-U, the first network segment according to the first message may include: the PGW-U judges whether a local session using the address in the first network segment exists or not according to the first message; if so, the PGW-U compares the time stamp for creating the local session with the first time stamp; and if the time stamp of the created local session is earlier than the first time stamp, the PGW-U releases the first network segment. Further, after step 303a, the method may further include: the PGW-U deletes the local session using the address in the first network segment.

And if the time stamp for creating the local session is later than the first time stamp, the PGW-U reserves the local session and does not release the first network segment. It should be noted that, if the timestamp for creating the local session is later than the first timestamp, which indicates that the newly activated session uses the address in the first network segment, the local session is retained. The optional method can prevent the mistaken deletion of the session and the mistaken release of the network segment.

The first message may use a private information element to carry information indicating the first network segment and/or the first timestamp.

304a, the PGW-U sends a second message to the PGW-C, the second message being used to indicate that the PGW-U releases the first network segment.

The second message may include information indicating the first network segment, such as an IP address of the first network segment, a mask of the first network segment, a start IP address and an end IP address of the first network segment, and the like. Further, the second message may further include information for indicating that the PGW-U releases the network segment, and of course, the information may also be indicated by a message type of the second message.

305a, the PGW-C receives a second message from the PGW-U, and releases the first network segment according to the second message.

The PGW-C releases the first network segment after the PGW-U releases the first network segment, so that the first network segment cannot be allocated to two PGW-Us, and the two PGW-Us are prevented from issuing the same network segment route.

After step 305a, the PGW-C may assign the first network segment to any one of the PGW-us for use.

During the steps 301, 302, 303a to 305a, if there is a session deactivation, multiple messages for releasing network segments in the PGW-U may be triggered, and the PGW-C may process multiple messages for releasing network segments in the PGW-U and response messages of these messages at the same time.

In another case (denoted as case 2), the PGW-U may not successfully receive the first message due to the Sxb interface link flashing or breaking, in which case, for the PGW-C, steps 303b and 304b may be performed after step 302, and for the PGW-U, step 303C may be performed after step 302.

303b, the PGW-C does not receive the response message of the first message, and the PGW-C sends the first message to the PGW-U at intervals.

It should be noted that, in the case that the link of the Sxb interface is flashed, the first message sent by the PGW-C subsequently may be received by the PGW-U, and in this case, the method shown in the above steps 303a to 305a may be performed.

The time intervals between the PGW-C sending two adjacent first messages may be the same or different, and may be specifically designed according to an actual application scenario.

304b, if the response message of the first message is not received in the first preset time period, the PGW-C releases the network segment allocated to the PGW-U.

The PGW-C may set a first timer, where a duration of the first timer is a first preset time period, and the PGW-C may start the first timer when sending a first message (that is, a starting time of the first preset time period is a time for sending the first message), and release a network segment allocated to the PGW-U when the first timer is overtime; or starting a first timer when determining Sxb interface link interruption (that is, the starting time of the first preset time period may be the time when the PGW-C determines Sxb interface link interruption), and releasing the network segment allocated to the PGW-U when the first timer expires. For example, the first preset time period may be 30 minutes.

After step 304b, the PGW-C may allocate the segment originally occupied by the PGW-U to any PGW-U for use.

The network segment occupied by the PGW-U comprises a first network segment.

During the steps 301, 302, 303b-304b, if there is session deactivation, multiple messages for releasing the network segment of the PGW-U may be triggered, and the PGW-C may process multiple messages for releasing the network segment of the PGW-U and response messages of these messages at the same time.

303C, the PGW-U determines that an Sxb interface link between the PGW-U and the PGW-C is broken, and the PGW-U releases the network segment distributed by the PGW-C in the PGW-U after a second preset time period.

The PGW-U may set a second timer, where a duration of the second timer is a second preset time period, and the PGW-U may start the second timer when determining Sxb interface link interruption (that is, a starting time of the second preset time period is a time when the PGW-U determines Sxb interface link interruption), and release a network segment allocated by the PGW-C in the PGW-U when the second timer is overtime. For example, the second preset time period may be 15 minutes.

The network segment distributed by the PGW-C in the PGW-U comprises a first network segment.

It should be noted that the first preset time period should be greater than the second preset time period to ensure that when the PGW-C releases the network segment allocated to the PGW-U, the network segment allocated to the PGW-C in the PGW-U is already released.

Optionally, after step 303c, the method further includes: the PGW-U deletes the local session using the address in the network segment assigned by the PGW-C. Because the number of sessions is large and the deletion time is possibly long, the PGW-U can release the network segment first and then delete the local session, so that two PGW-Us can be prevented from issuing the same network segment route.

The PGW-U in this embodiment may be any one of the PGW-Us corresponding to the PGW-C.

In the method provided in this embodiment, after the PGW-U releases the segment allocated to the PGW-U by the PGW-C in the PGW-U, the PGW-C releases the segment allocated to the PGW-U in the PGW-C, so that the same segment is not allocated to two PGW-us, that is, the two PGW-us do not issue the same segment route. This embodiment can solve the problems in scenario 1 and scenario 2 described above.

Example two

In order to release an invalid network segment in a PGW-U, an embodiment of the present application further provides a method for releasing a network segment, as shown in fig. 4, including:

401. the PGW-U determines an invalid network segment of the PGW-U through network segment verification with the PGW-C; the invalid network segment of the PGW-U refers to the network segment, except all the network segments which are recorded on the PGW-C and allocated to the PGW-U, of all the network segments allocated by the PGW-C in the PGW-U.

It should be noted that one PGW-C may correspond to multiple PGW-us, and the network segment check between the PGW-C and the multiple PGW-us may be performed concurrently. That is, the PGW-C may support simultaneous communication with multiple PGW-Us.

402. The PGW-U releases the invalid network segment of the PGW-U.

After step 402, the method may further comprise: the PGW-U deletes the local session using the address in the invalid segment of the PGW-U. Because the number of the sessions is large and the deletion time is possibly long, the PGW-U can release the invalid network segment firstly and then delete the local session, so that the two PGW-Us can be prevented from issuing the same network segment route, and meanwhile, the use of the invalid network segment can be recovered as early as possible.

Network segment verification may be performed between the PGW-U and the PGW-C at intervals (e.g., periodically), or may be performed in some scenarios, where the scenarios may be: the PGW-C causes the loss of the network segment information waiting to be released because of internal exception (for example, the process reset of the PGW-C); alternatively, the PGW-C senses Sxb that the interface link is recovering from an interruption to a connected state, etc.

The method provided in this embodiment may avoid that the PGW-U and the PGW-U occupying the invalid network segment of the PGW-U issue the same network segment route by releasing the invalid network segment of the PGW-U.

In one implementation, step 401 may include the following steps when implemented specifically:

11) and the PGW-C sends at least one checking request to the PGW-U, wherein the at least one checking request comprises the information of all network segments distributed to the PGW-U and recorded on the PGW-C.

If one checking request only includes information of part of network segments allocated to the PGW-U and recorded on the PGW-C, the PGW-C may send a plurality of checking requests to the PGW-U, where the plurality of checking requests include information for indicating all network segments allocated to the PGW-U and recorded on the PGW-C. Optionally, if the at least one checking request is a plurality of checking requests, a first checking request of the plurality of checking requests includes a Start flag bit, where the Start flag bit is used to indicate that the affiliated checking request is the first checking request, and a last checking request of the plurality of checking requests includes an End flag bit, where the End flag bit is used to indicate that the affiliated checking request is the last checking request.

The checking request can also carry the IP address of the PGW-C, and is used for indicating the PGW-C sending the checking request. One checking request may carry information of multiple network segments, and the PGW-C may carry information of as many network segments as possible on the principle that a message is not fragmented (in order to reduce consumption of an IP layer and/or a Transmission Control Protocol (TCP) layer).

12) The PGW-U receives at least one check request from the PGW-C.

13) And the PGW-U marks the network segments which belong to all the network segments distributed to the PGW-U and recorded on the PGW-C in the PGW-U according to the at least one checking request.

Exemplarily (denoted as example 1), if at least one of the verification requests includes information of segment 1, segment 2, and segment 3, and all segments allocated by the PGW-C in the PGW-U include segment 1, segment 2, segment 3, and segment 4, the PGW-U may mark segment 1, segment 2, and segment 3.

Exemplary (denoted as example 2), the marking may be a time stamp of the segment, for example, step 13), when implemented, may include: and the PGW-U refreshes the time stamps of all network segments distributed by the PGW-C in the PGW-U and the network segments which belong to all network segments distributed to the PGW-U and recorded on the PGW-C as second time stamps, wherein the second time stamps are used for indicating the time when the PGW-C sends the first checking request or the time when the PGW-U refreshes the time stamps according to the first checking request.

Wherein, when the second timestamp is used for indicating the time when the PGW-C sends the first checking request, the second timestamp may be included in the checking request. The second timestamp may be generated by the PGW-U itself, when the second timestamp is used to indicate the time when the PGW-U refreshed the timestamp according to the first check request.

14) And the PGW-U determines the unmarked network segment in all the network segments distributed by the PGW-C in the PGW-U as the invalid network segment of the PGW-U.

Based on example 1, PGW-U may determine segment 4 as an invalid segment of PGW-U.

Based on example 2, when time stamped, step 14) may, when embodied, include: and the PGW-U traverses the time stamps of all the network segments distributed by the PGW-C in the PGW-U, and determines the network segment with the time stamp earlier than the second time stamp as the invalid network segment of the PGW-U.

It should be noted that, because the timestamp of the network segment that is not allocated to the PGW-U and recorded on the PGW-C is not refreshed in the network segment checking process, the invalid network segment of the PGW-U may be determined according to the timestamp of the network segment of the PGW-U.

Wherein, the PGW-U may perform step 14) when receiving the last checking request. The PGW-U may determine whether a check request is the last check request according to whether the check request includes an end flag bit.

During segment verification, when a segment is newly established by receiving a session activation request from a user, the PGW-U also marks the segment (for example, marks a timestamp of the segment as a second timestamp).

In another implementation, step 401, when implemented, may include the following steps:

21) the PGW-U sends at least one checking request to the PGW-C, and the at least one checking request comprises information of all network segments distributed by the PGW-C in the PGW-U.

If one checking request only includes information of a part of network segments allocated by the PGW-C in the PGW-U, the PGW-U may send a plurality of checking requests to the PGW-C, where the plurality of checking requests include information indicating all network segments allocated by the PGW-C in the PGW-U. Optionally, if the at least one checking request is a plurality of checking requests, a first checking request of the plurality of checking requests includes a Start flag bit, where the Start flag bit is used to indicate that the affiliated checking request is the first checking request, and a last checking request of the plurality of checking requests includes an End flag bit, where the End flag bit is used to indicate that the affiliated checking request is the last checking request.

The checking request can also carry the IP address of the PGW-U, and is used for indicating the PGW-U which sends the checking request.

22) The PGW-C receives at least one checking request from the PGW-U, and judges whether each network segment of all network segments distributed by the PGW-C in the PGW-U is recorded on the PGW-C and distributed to the PGW-U or not according to the at least one checking request.

23) The PGW-C sends at least one checking response to the PGW-U, wherein the at least one checking response comprises information whether each network segment in all network segments allocated by the PGW-C in the PGW-U records the information allocated to the PGW-U on the PGW-C.

Exemplarily (denoted as example 3), if the at least one checking request includes information of the segment 1, the segment 2, and the segment 3, when the segment 1 and the segment 2 recorded by the PGW-C are segments allocated to the PGW-U, the at least one checking response indicates that the segment 1 and the segment 2 are yes, the segment 3 is no, yes indicates that the corresponding segment is the segment already allocated to the PGW-U recorded by the PGW-C, and no indicates that the corresponding segment is the segment not allocated to the PGW-U recorded by the PGW-C.

24) And the PGW-U receives at least one checking response from the PGW-C, and determines the network segment which is not allocated to the PGW-U and recorded on the PGW-C in all the network segments allocated by the PGW-C in the PGW-U as an invalid network segment of the PGW-U according to the at least one checking response.

Based on example 3, the PGW-U may determine segment 3 as an invalid segment for the PGW-U.

It should be noted that, the PGW-U may determine a partial invalid network segment of the PGW-U once and release a partial invalid network segment of the PGW-U every time a checking response is received, or the PGW-U may determine all invalid network segments of the PGW-U and release all invalid network segments of the PGW-U when all checking responses are received.

Optionally, if at least one of the check responses is a plurality of check responses, a last check response in the plurality of check responses includes an End (End) flag bit, where the End flag bit is used to indicate that the corresponding check response is the last check response. The PGW-U may determine whether one of the check responses is the last check response according to whether the end flag bit is included in the check response. In addition, the last one of the multiple checking responses may not include an End (End) flag bit, and in this case, the PGW-U may determine, according to whether each of all network segments allocated by the PGW-C in the PGW-U included in the checking responses records information allocated to the PGW-U on the PGW-C, whether the PGW-C has completely checked each of all network segments allocated by the PGW-C in the PGW-U, and further determine whether one checking response is the last checking response.

Two implementation manners of step 401 are exemplarily given above, and it can be understood that the essence of the scheme is network segment check through information interaction between the PGW-C and the PGW-U, and therefore, any scheme that determines an invalid network segment of the PGW-U through information interaction between the PGW-C and the PGW-U should fall within the protection scope of the embodiment of the present application.

EXAMPLE III

In order to ensure the consistency of information in the PGW-C and the PGW-U, the embodiment of the present application further provides a method for releasing a network segment, where the allocation of a network segment and the allocation of an address in a network segment are lost when the PGW-C is reset and restarted, and as shown in fig. 5, the method includes:

501. the PGW-C reset restarts.

502. The PGW-C refuses new session activation.

After the reset and restart, the PGW-C does not know which network segments are occupied by which PGW-us, so the PGW-C may reject new session activation, and if a session activation request is received, the PGW-C may return a response message of activation failure, thereby preventing the same network segment from being allocated to different PGW-us.

503. The PGW-C receives third messages and/or at least one fourth message sent by all PGW-Us connected with the PGW-C; and at least one fourth message sent by one PGW-U comprises the information of the network segment allocated to the PGW-U before the PGW-C in the PGW-U is reset and restarted.

The fourth message may indicate information of a partial or all network segments of a PGW-U through the private network element. When one fourth message cannot carry information of all network segments of the PGW-U, the PGW-U may send a plurality of fourth messages to the PGW-C, where the plurality of fourth messages include information of all network segments of the PGW-U. The last fourth message in the at least one fourth message may include an end flag bit, where the end flag bit is used to indicate that the fourth message to which the end flag bit belongs is the last fourth message, that is, the PGW-U finishes reporting information of all network segments of the PGW-U. The PGW-C may determine whether reporting of the PGW-U is completed according to whether the fourth message includes the end flag.

The first fourth message may be a system start Request message (i.e., a PFCP Association Setup Request message), and the remaining fourth messages may be PFCP Association Update Request messages (PFCP Association Update requests). Of course, the fourth message may also be a newly defined message.

504. The PGW-C allows new session activation.

Optionally, in step 503, if the PGW-C only receives at least one fourth message sent by all PGW-us connected to the PGW-C, the method further includes:

11) and the PGW-C allocates addresses in network segments for the newly activated session except the network segment allocated before the PGW-C in all the PGW-Us resets and restarts.

After the PGW-C receives at least one fourth message sent by all PGW-us connected to the PGW-C, the PGW-C knows which network segments are occupied by which PGW-us, so that the PGW-C may allow a new session to be activated, but an address allocated to the newly activated session should not reset, for the PGW-C in all PGW-us, an address in a network segment allocated before restarting, thereby preventing the same network segment from being allocated to a different PGW-U.

Taking the first PGW-U connected to the PGW-C as an example, after the first PGW-U determines that the PGW-C is reset and restarted, the following steps may be performed: 11) and the first PGW-U releases the network segment allocated to the first PGW-U before the PGW-C is reset and restarted.

The PGW-U can sense the reset and restart of the PGW-C through a heartbeat message of a PFCP interface. The first PGW-U is any one of the PGW-Us connected to the PGW-C.

If the network segment is released after the session is released, the network segment is released with a longer time delay due to too many sessions, so that the PGW-C cannot activate a new session, and the service is affected. In order to avoid the problem, in the embodiment of the application, the PGW-U releases the network segment firstly and then deletes the session, the release of the network segment does not depend on the deletion of the session, and the network segment is released firstly, so that the network segment can be ensured to be rapidly recovered.

Step 11), when implemented specifically, may include: and the first PGW-U releases the network segment with the timestamp before the PGW-C resets and restarts. It should be noted that each segment in the PGW-U corresponds to a timestamp, and the timestamp corresponding to one segment is used to indicate the time when the PGW-C allocates the segment to the PGW-U.

After step 11), optionally, the method further comprises: the first PGW-U sends a third message to the PGW-C, where the third message is used to indicate that the first PGW-U releases the network segment allocated to the first PGW-U before the PGW-C is reset and restarted.

Optionally, after step 11), the method further includes: the first PGW-U deletes the local session of the address in the network segment allocated to the first PGW-U before the PGW-C is reset and restarted; or the first PGW-U deletes the session established before the PGW-C reset restart.

Optionally, the method further includes: the first PGW-U sends at least one fourth message to the PGW-C, where the at least one fourth message includes information of a network segment of the first PGW-U.

21) the PGW-C locks the network segments distributed before the PGW-C in all the PGW-Us is reset and restarted;

22) the PGW-C receiving a third message from the first PGW-U;

23) and the PGW-C unlocks the network segment distributed to the first PGW-U before resetting and restarting the obtained PGW-C.

Locking a network segment means that the network segment is in a state that the network segment cannot be allocated. That is, when a network segment is locked, the network segment cannot be allocated. Unlocking a network segment refers to bringing the network segment into a state in which it can be allocated. That is, after a network segment is unlocked, the network segment can be allocated to any PGW-U.

It should be noted that, because the network segments of the timestamp of the first PGW-U are already released before the PGW-C resets and restarts, these network segments may be allocated to other PGW-us, so that the PGW-C unlocks these network segments, and the network segments after unlocking may be allocated to any one PGW-U.

The PGW-C locks the network segments of the PGW-U, so that the PGW-C can be prevented from distributing the network segments to other PGW-U before the PGW-U releases the network segments, and the two PGW-U are prevented from releasing the same network segment route.

The above-mentioned scheme of the embodiment of the present application is introduced mainly from the perspective of interaction between network elements. It will be appreciated that each network element, such as a control plane gateway or a data plane gateway, comprises corresponding hardware structures and/or software modules for performing each function in order to implement the above-described functions. Those of skill in the art would readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is performed as hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the embodiment of the present application, the control plane gateway or the data plane gateway may be divided into the functional units according to the above method, for example, each functional unit may be divided corresponding to each function, or two or more functions may be integrated into one processing unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit. It should be noted that the division of the unit in the embodiment of the present application is schematic, and is only a logic function division, and there may be another division manner in actual implementation.

In the case of an integrated unit, fig. 6 shows a schematic diagram of a possible structure of the communication device according to the above embodiment, where the communication device includes a processing unit 601, a communication unit 602, and a storage unit 603. The schematic structure shown in fig. 6 may be used to illustrate the structure of the control plane gateway or the data plane gateway in the above embodiments.

When the configuration diagram shown in fig. 6 is used to illustrate the configuration of the control plane gateway (e.g., PGW-C in fig. 3 to 5) involved in the foregoing embodiment, the processing unit 601 is configured to perform control management on the action of the control plane gateway, for example, the processing unit 601 is configured to support the control plane gateway to perform the actions performed by the control plane gateway in step 301, step 302, step 304a, step 305a, step 303b, and step 304b in fig. 3, step 401 in fig. 4, step 501 to step 504 in fig. 5, and/or other processes described in this embodiment of the present application. The communication unit 602 is configured to support communication between the control plane gateway and other network entities, for example, the data plane gateway shown in fig. 3. The storage unit 603 is used for storing program codes and data of the control plane gateway.

When the schematic structure diagram shown in fig. 6 is used to illustrate the structure of the data plane gateway (e.g., PGW-U in fig. 3 to 5) involved in the foregoing embodiments, the processing unit 601 is configured to control and manage the actions of the data plane gateway, for example, the processing unit 601 is configured to support the data plane gateway to perform the actions performed by the data plane gateway in step 302, step 303a, step 304a, step 303b, and step 303c in fig. 3, step 401 and step 402 in fig. 4, step 503 in fig. 5, and/or other processes described in this embodiment. The communication unit 602 is configured to support communication between the data plane gateway and other network entities, for example, the control plane gateway shown in fig. 3. The storage unit 603 is used to store program codes and data of the data plane gateway.

The processing unit 601 may be a processor or a controller, and the communication unit 602 may be a communication interface, a transceiver circuit, and the like, where the communication interface is generally referred to and may include one or more interfaces. The storage unit 603 may be a memory.

When the processing unit 601 is a processor, the communication unit 602 is a communication interface, and the storage unit 603 is a memory, the communication device according to the embodiment of the present application may be the communication device shown in fig. 2.

When the configuration diagram shown in fig. 2 is used to illustrate the configuration of the control plane gateway in the foregoing embodiment, the processor 201 is configured to control and manage the actions of the control plane gateway, for example, the processor 201 is configured to support the control plane gateway to perform the actions performed by the control plane gateway in steps 301, 302, 304a, 305a, 303b, and 304b in fig. 3, step 401 in fig. 4, steps 501 to 504 in fig. 5, and/or other processes described in this embodiment. The communication interface 204 is used to support communication between the control plane gateway and other network entities, for example, the data plane gateway shown in fig. 3. The memory 203 is used to store program codes and data for the control plane gateway.

When the schematic structure shown in fig. 2 is used to illustrate the structure of the data plane gateway in the above embodiment, the processor 201 is configured to control and manage the actions of the data plane gateway, for example, the processor 201 is configured to support the data plane gateway to perform the actions performed by the data plane gateway in step 302, step 303a, step 304a, step 303b, step 303c in fig. 3, step 401 and step 402 in fig. 4, step 503 in fig. 5, and/or other processes described in this embodiment. The communication interface 204 is used to support communication between the data plane gateway and other network entities, for example, the control plane gateway shown in fig. 3. The memory 203 is used to store program codes and data for the data plane gateway.

Embodiments of the present application also provide a computer-readable storage medium, which includes instructions that, when executed on a computer, cause the computer to perform any of the above methods.

Embodiments of the present application also provide a computer program product containing instructions which, when run on a computer, cause the computer to perform any of the methods described above.

The embodiment of the present application further provides a communication system, which includes the data plane gateway and the control plane gateway in the above embodiments.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented using a software program, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. The procedures or functions described in accordance with the embodiments of the present application are all or partially generated upon loading and execution of computer program instructions on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)), or wireless (e.g., infrared, wireless, microwave, etc.). Computer-readable storage media can be any available media that can be accessed by a computer or can comprise one or more data storage devices, such as servers, data centers, and the like, that can be integrated with the media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., Solid State Disk (SSD)), among others.

While the present application has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed application, from a review of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Although the present application has been described in conjunction with specific features and embodiments thereof, it will be evident that various modifications and combinations can be made thereto without departing from the spirit and scope of the application. Accordingly, the specification and figures are merely exemplary of the present application as defined in the appended claims and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of the present application. It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. A method for releasing a network segment, comprising:

the control plane gateway determines that no session uses the address in the first network segment; the first network segment comprises a plurality of addresses allocated to the session of the terminal equipment;

the control plane gateway sends a first message to a data plane gateway, wherein the first message is used for indicating the data plane gateway to release the first network segment, and the data plane gateway occupies the first network segment;

and the control plane gateway receives a second message from the data plane gateway, wherein the second message is used for indicating that the data plane gateway releases the first network segment, and the control plane gateway releases the first network segment according to the second message.

2. The method of claim 1, wherein the control plane gateway determining that no session uses an address in the first network segment comprises:

when the control plane gateway receives a deactivation request of a first session, the control plane gateway determines whether the first session is the last session using the address in the first network segment, and if so, the control plane gateway determines that no session uses the address in the first network segment.

3. The method according to claim 1 or 2, wherein a first timestamp is included in the first message, and the first timestamp is used for indicating the time when the control plane gateway sends the first message.

4. A method for releasing a network segment, comprising:

the method comprises the steps that a data plane gateway receives a first message from a control plane gateway, wherein the first message is used for indicating the data plane gateway to release a first network segment; the first network segment comprises a plurality of addresses allocated to the session of the terminal equipment;

the data plane gateway releases the first network segment according to the first message;

and the data plane gateway sends a second message to the control plane gateway, wherein the second message is used for indicating that the data plane gateway releases the first network segment.

5. The method of claim 4, wherein after the data plane gateway releases the first network segment in accordance with the first message, the method further comprises:

and the data plane gateway deletes the local session using the address in the first network segment.

6. The method according to claim 4 or 5, wherein a first timestamp is included in the first message, the first timestamp is used for indicating a time when the control plane gateway sends the first message, and the data plane gateway releases the first network segment according to the first message, including:

the data plane gateway judges whether a local session using the address in the first network segment exists or not according to the first message;

if so, the data plane gateway compares the time stamp for creating the local session with the first time stamp;

and if the time stamp for creating the local session is earlier than the first time stamp, the data plane gateway releases the first network segment.

7. A method for releasing a network segment, comprising:

the control plane gateway determines that no session uses the address in the first network segment;

the control plane gateway does not receive a response message of the first message, the control plane gateway sends the first message to the data plane gateway at intervals, and if the response message of the first message is not received in a first preset time period, the control plane gateway releases a network segment distributed to the data plane gateway; the starting time of the first preset time period is the time when the control plane gateway sends the first message, or the starting time of the first preset time period is the time when the control plane gateway determines that an interface link between the control plane gateway and the data plane gateway is interrupted;

the data plane gateway determines that an interface link between the data plane gateway and the control plane gateway is interrupted;

and the data plane gateway releases the network segment distributed by the control plane gateway in the data plane gateway after a second preset time period, wherein the second preset time period is less than the first preset time period.

8. The method of claim 7, further comprising:

and the data plane gateway deletes the local session using the address in the network segment distributed by the control plane gateway.

9. A communications apparatus, comprising: a memory and a processor;

the memory is configured to store computer-executable instructions, and the processor executes the computer-executable instructions stored by the memory to cause the communication device to: the method of any one of claims 1-3; or the method performed by the control plane gateway of claim 7 or 8.

10. A communications apparatus, comprising: a memory and a processor;

the memory is configured to store computer-executable instructions, and the processor executes the computer-executable instructions stored by the memory to cause the communication device to: the method of any one of claims 4-6; or the method performed by the data plane gateway of claim 7 or 8.

11. A computer-readable storage medium comprising instructions that, when executed on a computer, cause the computer to perform: the method of any one of claims 1-3; or the method performed by the control plane gateway of claim 7 or 8.

12. A computer-readable storage medium comprising instructions that, when executed on a computer, cause the computer to perform: the method of any one of claims 4-6; or the method performed by the data plane gateway of claim 7 or 8.