CN102025596B

CN102025596B - Processing method of route optimization, and device as well as communication system thereof

Info

Publication number: CN102025596B
Application number: CN 200910161964
Authority: CN
Inventors: 吴问付
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2009-09-10
Filing date: 2009-09-10
Publication date: 2012-12-12
Anticipated expiration: 2029-09-10
Also published as: CN102025596A

Abstract

The present invention discloses a processing method of route optimization, and a device as well as a communication system thereof. According to the technical solution of the invention, a route optimization PDN connection for UE is established by obtaining that UE allows only one establishment of PDN connection, or obtaining that the characteristic of UE is single application, or obtaining that UE is M2M equipment, then a route optimization processing for UE data is realized to decrease system load of gateway, at the same time, only one PDN connection for UE is ensured, thereby avoiding the case that a redundant PDN connection is established for UE, and saving resources of network side.

Description

Processing method and device for route optimization and communication system

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a processing method and apparatus for route optimization, and a communication system.

Background

Route optimization (Local Breakout), which may also be referred to as Local Breakout, Internet bypass (Internet Offload), Gi bypass (Gi Offload), Local Internet Protocol (IP) Access (Local IP Access), or selective IP transport bypass (Selected IP traffic), etc., is illustrated in fig. 1, which mainly refers to that a User Equipment (UE) accesses an IP Network (IP Network) directly through an Access Network, i.e., uplink data is directly connected from the UE to the IP Network through the Access Network, or downlink data is directly connected from the IP Network to the UE through the Access Network instead of the normal route Access to the IP Network, i.e., uplink data is connected from the UE to the IP Network through the Access Network and a gateway (GW, Gate Way), or downlink data is connected from the IP Network to the UE through the GW and the Access Network. It should be noted that the subscription database in fig. 1 mainly provides some data such as user information required when the user accesses the network. It should be noted that the IP network may also be referred to as a Packet Data Network (PDN).

The current method for establishing a route optimization path is as follows:

in the existing scheme 1, a UE establishes a default PDN connection in an Attach (Attach) procedure, and a subsequent UE initiates a PDN connection Request (PDN Connectivity Request) message, where the message carries a specific APN (that is, the APN is only used for a route-optimized PDN connection), and a core management network element determines whether to establish the route-optimized PDN connection according to the APN (that is, the PDN connection is established to an access side network element of an access network, instead of being established to a GW). Or,

in the existing scheme 2, a network side establishes a PDN connection of a normal route (that is, this PDN connection is established to a GW), configures a routing policy (for example, which traffic flows perform a routing optimization function, that is, which filter (filter) data flows perform a routing optimization function) in an access side network element of an access network, and after the access side network element of the access network receives an uplink data packet, the access side network element parses the uplink data packet to obtain a filter of the uplink data packet, and the access side network element determines whether the uplink data packet performs the routing optimization function according to the routing policy configured in the access side network element and the filter of the uplink data packet.

During the research and practice of the prior art, the inventor of the present invention found that for some applications, such as for Machine Type Communication applications (MTC, MTC application refers to network Communication between one or more network elements or devices without human intervention, i.e. Machine to Machine (M2M) applications, such as traffic control and management, factory monitoring, remote meter reading, etc), since its application is generally relatively simple, it is generally sufficient to establish one PDN connection, therefore, establishing multiple PDN connections according to the above-mentioned conventional scheme 1 wastes network resources, and requires configuring an APN used by a route-optimized PDN connection in the UE, and requires that the UE can distinguish an APN used by a normal-routed PDN connection from an APN used by a route-optimized PDN connection, thereby increasing the complexity of the UE.

Most of M2M applications are simple, and M2M devices only have a single service flow, so it is not necessary to perform the function of analyzing the uplink data packet in the access-side network element according to the above-mentioned prior art scheme 2, and performing the analysis of the uplink data packet will greatly affect the performance of the access-side network element, greatly increase the possibility of overloading the access-side network element, thereby causing the user service to receive a serious impact, and further affecting the user experience.

Disclosure of Invention

The embodiment of the invention provides a processing method and device for route optimization and a communication system, which can save network resources.

A processing method for route optimization, comprising:

acquiring information that the user equipment only allows to establish a single packet data network PDN connection, or acquiring information that the characteristic of the user equipment is single application, or acquiring information that the user equipment is machine-to-machine M2M equipment;

and performing route optimization for the user equipment according to the acquired information that the user equipment only allows to establish a single packet data network PDN connection, or the information that the characteristic of the user equipment is a single application, or the information that the user equipment is an M2M device.

A core management network element, comprising:

a first obtaining unit, configured to obtain information that a user equipment only allows establishing a single packet data network PDN connection, or obtain information that a characteristic of the user equipment is a single application, or obtain information that the user equipment is a machine-to-machine M2M device;

and the processing unit is configured to perform route optimization for the user equipment according to the information that the user equipment only allows establishment of a single packet data network PDN connection, or the information that the characteristic of the user equipment is a single application, or the information that the user equipment is an M2M device, acquired by the first acquiring unit.

A communication system includes any one of the core management network elements provided in the embodiments of the present invention.

The embodiment of the invention determines to establish the PDN connection with the route optimization for the UE by knowing that the UE only allows to establish one PDN connection or the characteristic of the user equipment is single application or the UE is M2M equipment, so that only one PDN connection is ensured to be established for the UE while the route optimization processing is realized for the data of the UE to reduce the system load of a gateway, the occurrence of the condition of establishing redundant PDN connection for the UE is avoided, and the resources of a network side are saved; or, the network element of the access side is instructed to execute route optimization, so that the subsequent network element of the access side receives the uplink data of the UE according to the instruction and directly sends the uplink data to the IP network without performing operations such as analysis of an uplink data packet and the like, and the processing in the network element of the access side is simplified, thereby saving the resources of the network side and improving the performance of the network element of the access side.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is an architectural diagram of route optimization;

FIG. 2 is a flow chart of a method according to an embodiment of the present invention;

FIG. 3 is a flowchart of a method provided in the second embodiment of the present invention;

FIG. 4 is a flowchart of a method provided in a third embodiment of the present invention;

FIG. 5 is a flowchart of a method provided by the fourth embodiment of the present invention;

FIG. 6 is a flowchart of a method provided in the fifth embodiment of the present invention;

FIG. 7 is a method flow diagram of a method provided by a sixth embodiment of the present invention;

FIG. 8 is a flowchart of a method provided by the seventh embodiment of the invention;

fig. 9 is a schematic structural diagram of a core management network element according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiment of the invention provides a processing method, a device and a communication system for route optimization, which can save network resources and simplify the processing of UE; or, the processing in the access side network element is simplified, the performance of the access side network element is improved, and the possibility of overload of the access side network element is reduced, thereby increasing the user experience. The following are detailed below.

The first embodiment,

The present embodiment will be described from the perspective of a core management network element.

A processing method of route optimization comprises the steps of obtaining information that a UE only allows to establish a single Packet Data Network (PDN) connection, or obtaining information that the characteristic of the UE is a single application, or obtaining information that the UE is a machine-to-machine (M2M) device; and performing route optimization for the UE according to the acquired information that the UE only allows to establish a single Packet Data Network (PDN) connection, or the information that the UE is characterized by a single application, or the information that the UE is an M2M device (namely determining that the route optimization needs to be performed for the UE according to the acquired information that the UE only allows to establish the single PDN connection, or the information that the UE is characterized by the single application, or the information that the UE is an M2M device, and performing route optimization processing for the UE). As shown in fig. 2, the specific process may be as follows:

101. acquiring information that the UE only allows to establish a single packet data network PDN connection, or acquiring information that the characteristic of the UE is single application, or acquiring information that the UE is machine-to-machine M2M equipment; specifically, the following may be mentioned:

(1) acquiring information that the UE only allows to establish single packet data network PDN connection;

for example, subscription data of the UE is obtained from a subscription database, where the subscription data includes the number of PDN connections allowed to be used by the UE, and if the number of PDN connections allowed to be used by the UE is 1, it is known that the UE only allows to establish a single PDN connection; or,

acquiring an M2M group identifier of the UE, acquiring the number of PDN connections allowed to be used according to the M2M group identifier, and if the number of PDN connections allowed to be used is 1, knowing that the UE only allows establishing a single PDN connection, specifically, the method may include one of the following ways:

A) and configuring a PDN connection number table in the core management network element, wherein the table comprises an M2M group identifier and the PDN connection number information allowed to be used by the group. The UE sends a message to a core management network element, and if the UE is an M2M device, the message may include an M2M group identifier. After receiving the message, if the discovery message includes an M2M group identifier, the core management network element queries the number of the PDN connections allowed to be used according to the M2M group identifier, and if the number of the PDN connections allowed to be used is 1, it is known that the UE only allows to establish a single PDN connection; or,

B) acquiring an M2M group identifier of the UE, acquiring M2M group subscription data from a subscription database according to the M2M group identifier, wherein the subscription data comprises the number of PDN connections allowed to be used (namely, the number of PDN connections allowed to be used by the UE in the M2M group), and if the number of PDN connections allowed to be used is 1, knowing that the UE only allows to establish a single PDN connection. Wherein, the M2M group id of the UE may be included in a message sent by the UE to the core management network element.

The M2M group may include a group consisting of M2M devices under MTC users (MTC users), or a group consisting of M2M devices under MTC subscribers (MTC subscribers).

It should be noted that the M2M group identifier may also be signed in subscription data of the UE, in which case the core management network element obtains the subscription data of the UE from the subscription database, and obtains the M2M group identifier from the subscription data of the UE.

The M2M group identifier described in the embodiment of the present invention includes an APN, i.e., an M2M group is identified according to the APN.

(2) Acquiring information that the characteristic of the UE is single application;

for example, subscription data of the UE is obtained from a subscription database, where the subscription data includes characteristic information of the UE, such as a characteristic cell MTC Feature cell of the UE, and if the characteristic information of the UE is a single application (single application), it is known that the characteristic of the UE is the single application; or,

acquiring an M2M group identity of the UE, acquiring the characteristic information according to the M2M group identity, and if the characteristic information is a single application, knowing that the characteristic of the UE is the single application, specifically, the method may include one of the following manners:

A) the core management network element configures the characteristics (features) of the M2M group, such as configuring an MTC characteristics table, where the table includes the M2M group id and the characteristics of the group. The UE sends a message to a core management network element, and if the UE is an M2M device, the message may include an M2M group identifier. After receiving the message, if the discovery message includes the M2M group identifier, the core management network element queries the configured characteristic according to the M2M group identifier, and if the configured characteristic is a single application, the core management network element learns that the characteristic of the UE is the single application; or,

B) acquiring an M2M group id of the UE, and acquiring M2M group subscription data from a subscription database according to the M2M group id, wherein the subscription data includes characteristic information of the M2M group (i.e., characteristic information of the UEs in the M2M group), such as a characteristic cell MTC Feature cell, and if the characteristic information of the M2M group is a single application (single application), it is known that the characteristics of the UEs in the M2M group are the single application. Wherein, the M2M group id of the UE may be included in a message sent by the UE to the core management network element.

(3) Acquiring information that the UE is machine-to-machine M2M equipment;

for example, subscription data of the UE is obtained from a subscription database, where the subscription data includes information that the UE is M2M, and the UE is known to be an M2M device according to the information that the UE is M2M; the UE M2M device information may include one of the following modes:

A) M2M indicates (M2M Indication) cells. If the M2M Indication cell is included in the subscription data of the UE, the UE is an M2M device, and otherwise, if the M2M Indication cell is not included in the subscription data of the UE, the UE is a non-M2M device.

B) non-M2M indicates (non-M2M Indication) cells. If the non-M2M Indication cell is included in the UE subscription data, the UE is a non-M2M device, otherwise, if the non-M2M Indication cell is not included in the UE subscription data, the UE is an M2M device.

C) M2M identifies the (M2M Flag) cell. If the value of the M2M Flag cell in the subscription data of the UE is 1, the UE is an M2M device, and otherwise, if the value of the M2MFlag cell in the subscription data of the UE is 0, the UE is a non-M2M device.

In addition to the above-mentioned subscription data of the UE obtained from the subscription database, the M2M group id of the UE may also be obtained, and if the M2M group id is included in the M2M device information table, the UE is known to be an M2M device. For example, the following may be used:

configuring an M2M device information table in a core management network element, wherein the information table comprises an M2M group identifier. And the UE sends a message to a core management network element, and if the UE is an M2M device, the message comprises an M2M group identifier. After receiving the message, the core management network element considers that the UE is M2M equipment if the M2M group identifier included in the discovery message exists in the M2M equipment information table; on the contrary, if there is no M2M group identity in the message or the M2M group identity included in the message does not exist in the M2M device information table, the core management network element considers the UE as a non-M2M device.

Of course, the UE may also report to indicate whether the UE is an M2M device, that is, the UE sends a message to the core management network element, where the message includes indication information of whether the UE is an M2M device, and the core management network element learns whether the UE is an M2M device according to the indication information after receiving the message. Wherein, the indication information may include one of the following modes:

A) the machine-to-machine Indication (M2M Indication) cell. If the UE is an M2M device, the message sent to the core management network element includes the M2M Indication cell; or, if the UE is a non-M2M device, the M2M Indication information element is not included in the message sent to the core management network element. After receiving the message sent by the UE, the core management network element learns whether the UE is an M2M device according to whether the message includes an M2M Indication cell.

B) Non-machine-to-machine Indication (non-M2M Indication) cell. If the UE is a non-M2M device, the message sent to the core management network element includes the M2M Indication cell; or, if the UE is an M2M device, the M2M Indication information element is not included in the message sent to the core management network element. After receiving the message sent by the UE, the core management network element learns whether the UE is an M2M device according to whether the message includes a non-M2M Indication cell.

C) Machine-to-machine Flag (M2M Flag) cell. If the UE is M2M equipment, the value of the M2M Indication cell in the message sent to the core management network element is 1; or, if the UE is a non-M2M device, the value of the M2M Indication information element in the message sent to the core management network element is 0. After receiving the message sent by the UE, the core management network element learns whether the UE is an M2M device according to whether the value of the M2M Indication cell in the message is 1 or 0.

The obtaining of the information that the UE is a machine-to-machine M2M device may also include obtaining an M2M group identifier of the UE, obtaining M2M group subscription data from a subscription database according to the M2M group identifier, where the subscription data includes information that the UE is M2M (i.e., information that the UEs in the M2M group are M2M), and knowing that the UE is an M2M device according to the information that the UE is M2M. Wherein, the M2M group id of the UE may be included in a message sent by the UE to the core management network element.

The UE M2M device information may include one of the following modes:

A) M2M indicates (M2M Indication) cells. If the M2M Indication cell is included in the subscription data of the M2M group, the UE is an M2M device, and otherwise, if the M2M Indication cell is not included in the subscription data of the M2M group, the UE is a non-M2M device.

B) non-M2M indicates (non-M2M Indication) cells. If the non-M2M Indication cell is included in the subscription data of the M2M group, the UE is a non-M2M device, and otherwise, if the non-M2M Indication cell is not included in the subscription data of the M2M group, the UE is an M2M device.

C) M2M identifies the (M2M Flag) cell. If the value of the M2MFlag cell in the subscription data of the M2M group is 1, it indicates that the UE is an M2M device, and if the value of the M2M Flag cell in the subscription data of the M2M group is 0, it indicates that the UE is a non-M2M device.

102. And performing route optimization for the UE according to the acquired information that the UE only allows to establish a single packet data network PDN connection, or the information that the characteristic of the UE is a single application, or the information that the UE is an M2M device. The method specifically comprises the following steps:

(1) establishing a PDN connection with optimized routing for the UE according to the acquired information that the UE only allows to establish a single PDN connection of the packet data network; or,

(2) establishing a PDN connection with optimized routing for the UE according to the acquired information of the single application of the characteristic of the UE; or,

(3) establishing a PDN connection with optimized routing for the UE according to the acquired information that the UE is M2M equipment; or,

(4) according to the acquired information that the UE only allows to establish a single packet data network PDN connection, indicating an access side network element to execute route optimization so that the access side network element executes route optimization processing after receiving an uplink data packet; or,

(5) according to the acquired information of the single application of the characteristics of the UE, indicating the access side network element to execute route optimization so that the access side network element executes route optimization processing after receiving an uplink data packet; or,

(6) and indicating the access side network element to execute route optimization according to the acquired information that the UE is the M2M device, so that the access side network element executes route optimization processing after receiving the uplink data packet.

The PDN connection for route optimization for the user equipment may specifically be: the method comprises the steps of obtaining an Internet Protocol (IP) address of an access side network element accessed by UE, sending a request message for establishing a session or a request message for establishing a Packet Data Protocol (PDP) context to the access side network element corresponding to the IP address, and then receiving a response message for establishing the session or the PDP context returned by the access side network element.

The instructing the access side network element to perform the route optimization specifically includes: the method comprises the steps that indication information is included in an initialization Context Setup Request (Initial Context Setup Request), a radio access Bearer allocation Request (RABAssignment Request) or a Bearer Setup Request (Bearer Setup Request) message sent to an access side network element, and the indication information indicates the access side network element to execute route optimization.

Wherein, the indication information in the three cases (i.e., (4), (5), (6)) indicating that the access-side network element performs the route optimization processing may include one of the following manners:

A) a route optimization usage Indication (LIPA Used Indication) information element. If the message includes the LIPA Used Indication cell, indicating the access side network element to execute route optimization processing; or, if the message does not contain the LIPA Used Flag information element, the network element at the access side is instructed not to execute the route optimization processing.

B) The route optimization does not use Indication (LIPA not-Used Indication) cell. If the message includes the liproot-Used Indication cell, the access side network element is indicated not to execute the route optimization processing; or, if the message does not contain the LIPA not-Used Flag cell, the access side network element is instructed to execute the route optimization processing.

C) A route optimization use Flag (LIPA Used Flag) cell. If the value of the LIPA UsedFlag information element in the message is 1, indicating that the network element at the access side is instructed to execute route optimization processing; or, if the value of the LIPA Used Flag information element in the message is 0, indicating that the access side network element is not instructed to execute the route optimization processing.

In addition to the information obtained in step 101, optionally, any one or a combination of information that the access-side network element supports route optimization and information that the UE is allowed to use route optimization may also be obtained; and then establishing the route-optimized PDN connection for the UE or instructing the access side network element to execute route optimization processing according to any one or combination of the information that the access side network element supports route optimization and the information that the UE is allowed to use the route optimization, and any one of the information that the UE only allows the establishment of a single packet data network PDN connection, the information that the characteristic of the UE is a single application and the information that the UE is an M2M device. That is, as follows:

(1) acquiring information that an access side network element supports route optimization, and then establishing a route-optimized PDN connection for the UE or instructing the access side network element to execute route optimization processing according to the information that the access side network element supports route optimization and the information that the UE only allows to establish a single packet data network PDN connection, or establishing a route-optimized PDN connection for the UE or instructing the access side network element to execute route optimization processing according to the information that the access side network element supports route optimization and the information that the UE has the characteristics of single application, or establishing a route-optimized PDN connection for the UE or instructing the access side network element to execute route optimization processing according to the information that the access side network element supports route optimization and the information that the UE is an M2M device.

(2) Acquiring information allowing the UE to use the route optimization, and then establishing a route-optimized PDN connection for the UE or instructing an access-side network element to execute route optimization processing according to the information allowing the UE to use the route optimization and the information allowing the UE to only establish a single packet data network PDN connection, or establishing a route-optimized PDN connection for the UE or instructing the access-side network element to execute route optimization processing according to the information allowing the UE to use the route optimization and the information allowing the UE to use the single packet data network PDN connection, or establishing a route-optimized PDN connection for the UE or instructing the access-side network element to execute route optimization processing according to the information allowing the UE to use the route optimization and the information allowing the UE to be M2M equipment.

(3) Acquiring information that an access side network element supports route optimization and information that a UE is allowed to use route optimization, then according to the information that the access side network element supports route optimization, the information that the UE is allowed to use the route optimization and the information that the UE is only allowed to establish a single packet data network PDN connection, establishing the route optimized PDN connection for the UE or instructing the access side network element to execute route optimization processing, or, according to the information that the access side network element supports route optimization, the information that the UE is allowed to use the route optimization and the information that the characteristic of the UE is single application, establishing a route-optimized PDN connection for the UE or instructing the access side network element to execute route optimization processing, or, according to the information that the access side network element supports route optimization, the information that the UE is allowed to use route optimization and the information that the UE is an M2M device, establishing a route-optimized PDN connection for the UE or instructing the access side network element to perform route optimization processing.

The obtaining of the information that the access side network element supports the route optimization may include one of the following manners:

1. if the access side network element supports the route optimization, a Message (e.g., an Initial UE Message) sent by the access side network element to the core management network element includes an Internet Protocol (IP) address (e.g., an IP address of a GPRS Tunneling Protocol (GTP) control plane of the access side network element) of the access side network element, and the core management network element obtains the information that the access side network element supports the route optimization according to the IP address of the access side network element.

2. And configuring in a core management network element. Configuring a list of access side network elements supporting route optimization in a core management network element, and acquiring information that the access side network elements support route optimization if the core management network element finds that the access side network elements accessed by the UE are in the configured list; or, configuring an access side network element configuration table in the core management network element, where the table includes an access side network element identifier and route optimization support indication information, and the core management network element obtains the access side network element identifier accessed by the UE, queries the access side network element configuration table according to the identifier, and queries the route optimization support indication information of the access side network element identifier in the table, and if the route optimization support indication information indicates that the access side network element supports route optimization, the core management network element learns that the access side network element supports route optimization.

3. The configuration server of the access side network element (the main function of the server is to perform the configuration of the access side network element). The method comprises the steps that a list of access side network elements supporting route optimization is configured in an access side network element configuration server, a core management network element sends a query request message to the access side network element configuration server, the message contains an access side network element identifier accessed by UE, the access side network element configuration server learns the information that the access side network elements support route optimization if the access side network elements accessed by the UE are found in the configured list, and the access side network element configuration server sends the learned information that the access side network elements support route optimization to the core management network element. Or,

an access side network element configuration server configures an access side network element configuration table, the table comprises an access side network element identifier and route optimization support indication information, a core management network element sends a query request message to the access side network element configuration server, the message comprises the access side network element identifier accessed by UE, the access side network element configuration server queries the access side network element configuration table according to the identifier, the route optimization support indication information of the access side network element identifier in the table is queried, if the route optimization support indication information indicates that the access side network element supports route optimization, the access side network element configuration server learns the information that the access side network element supports route optimization, and the access side network element configuration server sends the learned information that the access side network element supports route optimization to the core management network element.

Obtaining information that allows the UE to use route optimization may include one of:

acquiring subscription data of the UE from a subscription database, wherein the subscription data comprises information allowing the use of route optimization; wherein, the information allowing to use the route optimization may comprise one of the following modes:

A) route optimization admission Indication (LIPA Allowed Indication) cells. If the indication information element is included in the subscription data of the UE, the UE indicates that the route optimization is allowed to be used, and otherwise, if the indication information element is not included in the subscription data of the UE, the UE indicates that the route optimization is not allowed to be used.

B) The route optimization disallows Indication (LIPA not Allowed Indication) cells. If the indication information element is included in the subscription data of the UE, the UE indicates that the route optimization is not allowed to be used, and otherwise, if the indication information element is not included in the subscription data of the UE, the UE indicates that the route optimization is allowed to be used.

C) Route optimization allows identification of (LIPA Allowed Flag) cells. If the value of the cell in the subscription data of the UE is 1, the cell indicates that the route optimization is allowed to be used, and if the value of the cell in the subscription data of the UE is 0, the cell indicates that the route optimization is not allowed to be used.

Or,

obtain the M2M group identity of the UE, and obtain M2M group subscription data from the subscription database according to this M2M group identity, wherein the subscription data includes information that allows route optimization to be used (i.e., UEs within the M2M group are allowed to use route optimization). Wherein the information allowing the use of route optimization is specifically referred to the above description. Wherein, the M2M group id of the UE may be included in a message sent by the UE to the core management network element;

or,

configuring a list of M2M groups allowing the use of route optimization in a core management network element, acquiring an M2M group identifier of the UE by the core management network element, and acquiring information allowing the UE to use the route optimization if the core management network element finds that the M2M group identifier of the UE is in the configured list; or, configuring an M2M group configuration table in the core management network element, where the table includes an M2M group identifier and route optimization permission indication information, the core management network element obtaining the M2M group identifier of the UE, querying the M2M group configuration table according to the identifier, querying the route optimization permission indication information of the M2M group identifier in the table, and if the route optimization permission indication information indicates that the UE is permitted to use route optimization, the core management network element knows the information that the UE is permitted to use route optimization; the M2M group id of the UE may be included in a message sent by the UE to the core management network element, or the core management network element obtains subscription data of the UE from the subscription database, and obtains the M2M group id from the subscription data of the UE.

The M2M group configuration server (the main function of this server is to perform the configuration of the M2M group). Configuring an M2M group list allowing the use of route optimization in an M2M group configuration server, sending a query request message to an M2M group configuration server by a core management network element, wherein the message contains an M2M group identifier of a UE, learning information of allowing the M2M group to use route optimization (namely, allowing the UEs in the M2M group to use route optimization) if the M2M group identifier of the UE is found in the configured M2M group list by the M2M group configuration server, and sending the learned information of allowing the use of route optimization to the core management network element by the M2M group configuration server.

Or,

an M2M group configuration table is configured in an M2M group configuration server, the table comprises an M2M group identifier and route optimization permission indication information, a core management network element sends a query request message to the M2M group configuration server, the message comprises an M2M group identifier of a UE, the M2M group configuration server queries an M2M group configuration table according to the identifier, queries the route optimization permission indication information of the M2M group identifier in the table, if the route optimization permission indication information indicates that the M2M allows the use of route optimization (namely, allows the UE in the M2M group to use route optimization), the M2M group configuration server learns the information that the M2M group is allowed to use route optimization (namely, allows the UE in the M2M group to use route optimization), and the M2M group configuration server sends the learned information that the route optimization is allowed to the core management network element.

In order to ensure that only one PDN connection is established, after acquiring information that the UE only allows establishing a single PDN connection, or information that the UE is characterized as a single application, or information that the UE is a machine-to-machine M2M device, after establishing one PDN connection (route-optimized PDN connection or normal PDN connection), rejecting another PDN connection establishment request may be included; that is, at this time, if a PDN connection Request or an Activate Packet Data Protocol context Request (active PDP context Request, where the PDP is a Packet Data Protocol) message sent by the UE is received, the core management network element may Reject, for example, may return a PDN connection Reject (pdnconnection Reject) message or an Activate PDP context Reject (active PDP context Reject) message to the UE.

After the information that the UE only allows to establish the single PDN connection, or the information that the characteristic of the UE is single application, or the information that the UE is M2M equipment is obtained, route-optimized PDN connection is established for the UE according to the obtained information that the UE only allows to establish the single PDN connection, the information that the characteristic of the UE is single application, or the information that the UE is M2M equipment, so that the subsequent access side network element directly sends uplink data to an IP network after receiving the uplink data on the route-optimized PDN connection, or the IP network sends downlink data to the access side network element through the route-optimized PDN connection, and the access side network element sends the downlink data to the UE again. Or,

after the information that the UE only allows to establish a single PDN connection, or the information that the characteristic of the UE is single application, or the information that the UE is M2M equipment is obtained, the access side network element is instructed to perform route optimization according to the obtained information that the UE only allows to establish the single PDN connection, the information that the characteristic of the UE is single application, or the information that the UE is M2M equipment, so that the subsequent access side network element receives uplink data of the UE according to the instruction and then directly sends the uplink data to the IP network without performing operations such as analysis of uplink data packets.

In addition, optionally, before acquiring the information that the user equipment only allows to establish a single PDN connection, or acquiring the information that the characteristic of the user equipment is a single application, or acquiring the information that the user equipment is an M2M device, the method further includes: and receiving an update request message or a service request message sent by the user equipment.

The obtaining information that the user equipment only allows to establish a single PDN connection, or obtaining information that the characteristic of the user equipment is a single application, or obtaining information that the user equipment is an M2M device further includes: and when the change of an access side network element or the old PDN connection is known to be the PDN connection of the normal route, and the information that the user equipment only allows to establish a single PDN connection is obtained, or the information that the characteristic of the user equipment is single application is obtained, or the information that the user equipment is M2M equipment is obtained, and the PDN connection with the route optimization established for the UE is determined, the user equipment is instructed to initiate an attachment process. That is, another embodiment of the present invention may be:

receiving an update request message or a service request message sent by UE;

acquiring that an access side network element changes or an old PDN connection is a normally routed PDN connection, and indicating UE to initiate an attachment process when the routing-optimized PDN connection is established for the UE according to information that the user equipment only allows to establish a single PDN connection of a packet data network, or information that the characteristic of the user equipment is single application, or information that the user equipment is machine-to-machine M2M equipment;

after the UE initiates an attach process, the network side performs route optimization for the UE according to the acquired information that the UE only allows to establish a single Packet Data Network (PDN) connection, or the information that the characteristic of the UE is a single application, or the information that the UE is an M2M device.

It should be noted that the core Management Network element described in the embodiment of the present invention may include a Mobility Management Entity (MME), a Serving GPRS Support Node (SGSN), or a Mobility Management Network element in a non-third Generation Partnership Project (3 GPP) Network, such as an Evolved Packet Data Gateway (EPDG) in a Wireless Local Area Network (WLAN), an Evolved Packet Data Gateway (EPDG) in a worldwide interoperability for Microwave Access (Wimax) Network, an Access Service Gateway (GW) in a worldwide interoperability for Microwave Access Network, a Code Division Multiple Access (CDMA) Network, an Access Gateway (AGW, Gateway) in a Code Division Multiple Access (CDMA) Network, or a High Rate Packet Data Gateway (hsdp) in a High Rate Packet Data Gateway (hsdp), HRPD Serving Gateway), etc.

The UE may include a general terminal Device or an M2M Device, wherein the M2M Device may also be referred to as a Machine Type Communication Device (MTC Device).

The Access side Network element of the Access Network includes an Evolved base station (eNodeB) Network element in an Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) Network, an Access side gateway, a Home Evolved node NodeB (HeNB) Network element or a Home Access side gateway (HeNB GW) Network element operating in an E-UTRAN spectrum, a base station (NodeB) Network element in a UTRAN Network, a Radio Network Controller (RNC, Radio Network Controller) Network element, an Access side gateway, a Home NodeB (HNB, Home NodeB) Network element or hnbgw operating in a UTRAN spectrum, or a related Access side Network element in a non-3GPP Network (e.g., a non-3GPP Network such as CDMA, Wimax, WLAN, or HRPD).

The GW includes Network elements such as a Gateway Packet radio service support node (GGSN), a Serving Gateway (SGW), or a Packet Data Network Gateway (PDN GW).

The subscription database may include network elements such as a Home Location Register (HLR) or a Home Subscription Server (HSS).

The IP network includes an Internet network, an enterprise network, or an M2M application network (e.g., MTC Server), etc.

As can be seen from the above, in the embodiments of the present invention, the route-optimized PDN connection is determined to be established for the UE by obtaining that the UE only allows to establish one PDN connection, or obtains that the characteristic of the UE is a single application, or obtains that the UE is an M2M device, so that while the route optimization processing is implemented for the data of the UE to reduce the system load of the gateway, it is ensured that only one PDN connection is established for the UE, and the occurrence of the situation of establishing a redundant PDN connection for the UE is avoided, thereby saving resources on the network side and simplifying the processing of the UE. Or, by obtaining that the UE only allows establishing a PDN connection or obtains that the characteristic of the UE is a single application or obtains that the UE is an M2M device, it is determined to instruct the access-side network element to perform the route optimization, so that the access-side network element directly performs the route optimization after receiving the uplink packet (i.e., the access-side network element directly sends the uplink packet to the PDN instead of to the GW), which not only implements the route optimization of the data of the UE, but also implements the bypass of the data of the UE (i.e., does not pass through the gateway network element), reduces the system load of the gateway network element, and since the access-side network element does not need to perform the analysis of the uplink packet, the processing in the access-side network element is simplified, the performance of the access-side network element is improved, the possibility of overloading the access-side network element is reduced, and thereby the experience of the user is increased.

Example II,

The method according to the first embodiment will be described in detail by way of example.

This embodiment will be described by taking the PDN connection establishment in the Attach procedure as an example, as shown in fig. 3, the specific procedure may be as follows:

201. UE sends an Attach Request (Attach Request) message to an access side network element of an access network;

optionally, the attach request message may include indication information of whether the UE is an M2M device, and the specific processing of the indication information refers to the description in the first embodiment.

Optionally, the attach request message may further include an M2M group identifier.

202. An access side network element sends an initialization UE Message (Initial UE Message) to a core management network element, wherein the initialization UE Message comprises an attachment request Message sent by UE;

optionally, the initialization UE message carries an Internet Protocol (IP) address of a GPRS Tunneling Protocol (GTP) control plane with the access network element.

203. After the core management network element receives the Attach Request message, if the core management network element does not have valid subscription data of the UE, the core management network element acquires the subscription data of the UE from a subscription database, and if the core management network element sends an Update Location Request message to the subscription database; and returning an Update Location acknowledgement (Update Location Ack) message to the core management network element by the subscription database, wherein the message carries subscription data of the UE, and the subscription data of the UE comprises Access Point Name (APN) information. And if the APN used by the PDN connection with the optimized routing is different from the APN used by the PDN connection with the normal routing, the subscription data of the UE comprises the APN used by the PDN connection with the optimized routing and the APN used by the PDN connection with the normal routing. Of course, the subscription data of the UE may also include information about the number of PDN connections allowed to be used by the UE, or may include M2M group id, or may include characteristics of the UE, or may include information about the UE being an M2M device, or may also include information about whether the UE is allowed to use route optimization, or the like.

It should be noted that, if the core management network element already has valid subscription data of the UE, the core management network element obtains the stored subscription data of the UE without obtaining the subscription data of the UE from the subscription database.

204. If the core management network element obtains information that the UE only allows to establish a single PDN connection, or the core management network element obtains information that the characteristic of the UE is single application, or the core management network element obtains information that the UE is M2M equipment, the core management network element determines that the PDN connection established for the UE is the PDN connection with optimized routing, otherwise, the PDN connection established for the UE by the core management network element is the PDN connection with normal routing. The specific processing is described in example 1.

Optionally, the core management network element may obtain whether the access side network element supports the route optimization information, and then the core management network element establishes the route optimized PDN connection for the UE according to the access side network element support route optimization information and the UE only allows to establish the single PDN connection information; or the core management network element establishes a PDN connection for route optimization for the UE for the single application information according to the route optimization information supported by the access side network element and the characteristics of the UE; or, the core management network element establishes a route-optimized PDN connection for the UE according to the information that the access-side network element supports route optimization and the information that the UE is an M2M device; otherwise, the core management network element establishes the PDN connection of the normal route. The specific processing is described in example 1.

Optionally, the core management network element may obtain information on whether the UE is allowed to use route optimization, and then the core management network element establishes a route-optimized PDN connection for the UE according to the information on whether the UE is allowed to use route optimization and whether the UE is allowed to establish only a single PDN connection; or the core management network element establishes route optimized PDN connection for the UE for the single application information according to the route optimization allowed by the UE and the characteristics of the UE; or the core management network element establishes route-optimized PDN connection for the UE according to the route optimization allowed by the UE and the information that the UE is M2M equipment; otherwise, the core management network element establishes the PDN connection of the normal route. For specific processing, refer to the description in the first embodiment, and are not described herein again.

Optionally, the core management network element may obtain whether the UE is allowed to use the route optimization information and obtain whether the access side network element supports the route optimization information, and then the core management network element establishes a route-optimized PDN connection for the UE according to the route optimization allowed to be used by the UE, the route optimization supported by the access side network element, and only single PDN connection information allowed to be established by the UE; or the core management network element establishes a route-optimized PDN connection for the UE for the single application information according to the characteristics of allowing the UE to use route optimization, the access side network element to support route optimization and the UE; or the core management network element establishes a route-optimized PDN connection for the UE according to the information that the UE is allowed to use route optimization, the access side network element supports route optimization and the UE is M2M equipment; otherwise, the core management network element establishes the PDN connection of the normal route. For details, reference may be made to the first embodiment, which is not described herein again.

And if the core management network element determines that the established PDN connection is the PDN connection with optimized routing, the core management network element acquires the IP address of the access side network element accessed by the UE, and initiates a PDN connection establishment program to establish the PDN connection to the access side network element corresponding to the IP address. The core management network element may send a Create Session Request (Create Session Request) message to an access side network element to which the UE accesses, where the message includes an APN used for a PDN connection with optimized routing. And after the access side network element creates the resources of the PDN connection with optimized routing, returning a Create Session Response (Create Session Response) message to the core management network element.

It should be noted that, if the APN used by the route-optimized PDN connection is different from the APN used by the PDN connection routed normally, the APN selected by the core management network element in this step is the APN used by the route-optimized PDN connection.

The acquiring, by the core management network element, the IP address of the access-side network element to which the UE accesses may include one of the following manners:

1. the Initial UE Message sent by the access side network element to the core management network element includes an IP address of the access side network element.

2. And configuring in a core management network element. And the core management network element is configured with the IP address of the access side network element, and the core management network element inquires a configuration table according to the access side network element accessed by the UE to obtain the IP address of the access side network element.

3. The configuration server of the access side network element (the main function of the server is to perform the configuration of the access side network element). The IP address of the access side network element is configured in the access side network element configuration server, the core management network element sends a query request message to the access side network element configuration server, the message comprises an access side network element identifier accessed by the UE, the access side network element configuration server queries a configuration table according to the access side network element identifier to acquire the IP address of the access side network element, and the access side network element configuration server sends the acquired IP address information of the access side network element to the core management network element.

205. If the core management network element determines that the PDN connection established for the UE is a PDN connection of a normal route in step 204, the core management network element selects an APN (i.e., a default APN) used by the PDN connection of the normal route, performs a GW selection function according to the APN, selects a GW used by the PDN connection of the normal route, and then initiates a PDN connection establishment procedure to establish the PDN connection to the selected GW. The core management network element may send a Create Session Request (Create Session Request) message to the selected GW, where the message includes an APN used by a PDN connection of a normal route. The GW returns a Create Session Response (Create Session Response) message to the core management network element, and the method of establishing a PDN connection of a normal route may specifically follow the existing scheme, and is not described herein again.

It should be noted that, if the APN used by the route-optimized PDN connection is different from the APN used by the normally routed PDN connection, the core management network element selects the APN used by the normally routed PDN connection in this step.

206. The core management network element sends an Attach Accept (Attach Accept) message to the UE.

In addition, it should be noted that, if the core management network element obtains that the UE only allows to establish a single PDN connection message, or the core management network element learns that the characteristic of the UE is a single application, or the core management network element learns that the UE is an M2M device, the core management network element rejects another PDN connection establishment Request after establishing a route-optimized PDN connection or a normal route PDN connection in the Attach procedure, that is, if the core management network element receives a PDN connection Request (PDN Connectivity Request) message or an Activate PDP context Request (Activate PDP context Request) message sent by the UE, the core management network element rejects the Request of the UE, returns the PDN connection rejection message or activates the PDP context rejection message to the UE. This ensures that only one PDN connection is established for the UE.

As can be seen from the above, in this embodiment, by knowing that the UE only allows to establish one PDN connection, or knowing that the characteristic of the UE is a single application, or knowing that the UE is an M2M device, it is determined that the PDN connection established for the UE is a route-optimized PDN connection, which not only implements the route-optimized processing of the data of the UE, but also implements the bypass processing of the data of the UE (i.e., without passing through a gateway), reduces the system load of the gateway, but also establishes only one PDN connection for the UE, avoids establishing a redundant PDN connection for the UE, saves resources on the network side, and simultaneously, an APN used for the route-optimized PDN connection or an APN used for the normal route PDN connection is selected by a core management network element, without configuring an APN used for the route-optimized PDN connection in the UE, and without the UE being able to distinguish the APN used for the normal route-optimized PDN connection from the APN used for the route-optimized PDN connection, the processing of the UE is simplified.

Example III,

The difference between this embodiment and the second embodiment is that the PDN connection in the second embodiment is established in the Attach procedure, and this embodiment will be described by taking the PDN connection established after the Attach procedure as an example. Specifically, the PDN connection is established in a PDN connection (UE Requested PDN connectivity) procedure Requested by the UE or in a PDP Context Activation (PDP Context Activation) procedure. As shown in fig. 4, the specific process may be as follows:

steps 301 to 303 are the same as steps 201 to 203 in the second embodiment, and step 304 is the same as step 206 in the second embodiment, and are not repeated herein.

305. The UE sends a PDN connection Request (PDN Connectivity Request) message or an Activate PDP context Request (Activate PDP context Request) message to a core management network element.

306. If the core management network element obtains that the UE only allows to establish single PDN connection information, or the core management network element obtains that the characteristics of the UE are single application, or the core management network element obtains that the UE is M2M equipment, the core management network element determines that the PDN connection established for the UE is the PDN connection with optimized routing, otherwise, the core management network element establishes that the PDN connection established for the UE is the PDN connection with normal routing. The specific processing is described in example 1.

And if the core management network element determines that the established PDN connection is the PDN connection with optimized routing, the core management network element acquires the IP address of the access side network element accessed by the UE, and initiates a PDN connection establishment program to establish the PDN connection to the access side network element corresponding to the IP address. The core management element may send a Create session Request message or a Create PDP Context Request (Create PDP Context Request) message to an access side element to which the UE accesses, where the message includes an APN used for the route-optimized PDN connection. And after the access side network element creates the resources of the PDN connection with optimized routing, returning a Create session Response message or a Create PDP Context Response (Create PDP Context Response) message to the core management network element.

The description of the second embodiment refers to the core management network element acquiring the IP address of the access side network element accessed by the UE.

307. If the core management network element determines that the PDN connection established for the UE is a PDN connection of a normal route in step 306, the core management network element selects an APN used by the PDN connection of the normal route, performs a GW selection function according to the APN, selects a GW used by the PDN connection of the normal route, and then initiates a PDN connection establishment procedure to establish the PDN connection to the selected GW. The core management network element sends a message of creating a session Request or a message of creating a PDP Context Request (Create PDP Context Request) to the selected GW, wherein the message contains APN used by PDN connection of normal routing. The GW returns a Create session Response message or a Create PDP Context Response (Create PDP Context Response) message to the core management network element.

In addition, it should be noted that, if the core management element acquires that the UE only allows to establish a single PDN connection message, or the core management element learns that the characteristic of the UE is a single application, or the core management element learns that the UE is an M2M device, the core management element rejects other PDN connection establishment requests after establishing a route-optimized PDN connection or a normal route PDN connection for the UE, that is, the core management element rejects the UE request after receiving the PDN connection request message or the PDP context activation request message sent by the UE, and returns the PDN connection rejection message or activates the PDP context rejection message to the UE. This ensures that only one PDN connection is established for the UE.

Example four,

The present embodiment describes the processing in the update request or service request flow, and is different from the implementation two, in the present embodiment, the UE initiates the update request or service request. As shown in fig. 5, the specific process may be as follows:

401. the UE sends an Update Request (Update Request) message or a service Request (ServiceRequest) message to an access side network element (called a target access side network element) of a target access network; it should be noted that the access side network in this embodiment refers to a target access side network element.

Optionally, the update request message or the service request message may include indication information whether the UE is an M2M device, and the specific processing of the indication information may be as described in the first embodiment.

Optionally, the update request message or the service request message includes the M2M group identifier.

The Update Request in this step may be a Tracking Area Update Request (TAU Request, where TAU is Tracking Area Update, that is, Tracking Area) message or a routing Area Update Request (RAU Request, where RAU is routing Area Update, that is, routing Area) message, and the like.

402. The target access side network element sends an initialization UE Message (Initial UE Message) to the core management network element, wherein the initialization UE Message comprises an Update Request (Update Request) Message or a service Request Message sent by the UE. Optionally, the initialization UE message carries an IP address of the target access side network element.

403. After receiving the Update Request message or the service Request message, if the core management network element does not have valid subscription data of the UE, the core management network element obtains the subscription data of the UE from the subscription database, e.g., the core management network element sends an Update Location Request (Update Location Request) message to the subscription database; and returning an Update Location acknowledgement (Update Location Ack) message to the core management network element by the subscription database, wherein the message carries subscription data of the UE, and the subscription data of the UE can include APN information. Certainly, the subscription data of the UE may also include a PDN connection number cell that the UE allows to use; alternatively, an M2M group identification may be included; alternatively, the characteristics of the UE may be included; alternatively, UE M2M device information may be included; or may include whether the UE is allowed to use the route optimization information, etc.

404. If the core management network element determines to establish a route-optimized PDN connection for the UE and the core management network element finds that the access-side network element changes (for example, the core management network element finds that an IP address of a GTP control plane of a target access-side network element is different from an IP address of a GTP control plane of a source access-side network element, and the like); or, if the core management network element determines to establish a route-optimized PDN connection for the UE and the core management network element finds that the old PDN connection is a normally routed PDN connection (e.g., the core management network element finds that the old PDN connection is established to the GW); or, if the core management network element determines to establish a normally optimized PDN connection for the UE and the core management network element finds that the old PDN connection is a route optimized PDN connection (e.g., the core management network element finds that the old PDN connection is established to the access-side network element), the core management network element instructs the UE to initiate an Attach procedure. The core management network element sends an Update Reject (Update Reject) message or a Service Reject (Service Reject) message or a Detach Request (Detach Request) message to the UE, wherein these messages may include indication information to instruct the UE to initiate an Attach procedure, for example, a Cause value in the message is set to "Re-Attach".

The processing of the core management network element determining whether the established PDN connection is a route-optimized PDN connection or a normal-routed PDN connection is the same as that in embodiment two, and details are not repeated here.

Steps 405 to 407 are the same as steps 201 to 203 in the second embodiment, and will not be described in detail here.

408. A core management network element initiates a PDN connection deletion procedure to delete an old PDN connection (which may also be referred to as a source PDN connection);

if the old PDN connection is the PDN connection with optimized routing, the core management network element sends a Delete Session Request (Delete Session Request) message or a Delete PDP context Request (Delete PDP PContextRequest) message to the source access side network element, and then the source access side network element returns a Delete Session Response (Delete Session Response) message or a Delete PDP context Response (Delete PDP ContextResponse) message to the core management network element.

If the old PDN connection is the PDN connection of the normal route, the core management network element sends a Delete Session Request (Delete Session Request) message or a Delete PDP Context Request (Delete PDP Context Request) message to the GW, and the GW returns a Delete Session Response (Delete Session Response) message or a Delete PDP Context Response (Delete PDP Context Response) message to the core management network element.

Steps 409, 410, 411 are the same as steps 204, 205, 206 in embodiment two, and will not be described in detail here.

As can be seen from the above, in this embodiment, the core management network element instructs the UE to initiate the Attach procedure in the Update procedure or the service request procedure, delete the old PDN connection in the Attach procedure, and create a new PDN connection, so as to solve the problem that the old PDN connection deleted in the Update (Update) procedure or the service request procedure causes the UE to be in a detached state, thereby causing an abnormal procedure, and a new PDN connection cannot be created, which affects user experience, and determine that the PDN connection established for the UE is the route-optimized PDN connection by knowing that the UE only allows to establish one PDN connection, or knowing that the characteristic of the user equipment is a single application, or knowing that the UE is an M2M device, thereby not only implementing the route-optimized processing of data of the UE, reducing the system load of the gateway, but also establishing only one PDN connection for the UE, avoiding redundant PDN connection established for the UE, and saving resources on the network side, meanwhile, the APN used by the PDN connection with the optimized routing or the APN used by the PDN connection with the normal routing is selected by the core management network element, the APN used by the PDN connection with the optimized routing does not need to be configured in the UE, the APN used by the PDN connection with the normal routing and the APN used by the PDN connection with the optimized routing do not need to be distinguished by the UE, and the processing of the UE is simplified.

Example V,

The difference between this embodiment and the fourth embodiment is that the newly-established PDN connection in the fourth embodiment is established in the Attach procedure, but this embodiment will be described by taking the establishment of the PDN connection after the Attach procedure as an example, and specifically, the newly-established PDN connection may be established in a PDN connection procedure requested by the UE or in a PDP context activation procedure.

Steps 501 to 508 are the same as steps 401 to 408 of the fourth embodiment, step 509 is the same as steps 405 to 407 of the fourth embodiment, and steps 510 to 512 are the same as steps 305 to 307 of the third embodiment, and will not be described in detail here.

As can be seen from the above, in this embodiment, the core management network element instructs the UE to initiate the Attach procedure in the Update request procedure or the service request procedure, delete the old PDN connection in the Attach procedure, and create a new PDN connection, so as to solve the problem that the old PDN connection deleted in the Update (Update) procedure or the service Update procedure causes the UE to be in a detached state, thereby causing an abnormal procedure, and a new PDN connection cannot be created, which affects user experience, and determine that the PDN connection established for the UE is the route-optimized PDN connection by knowing that the UE only allows to establish one PDN connection, or knowing that the characteristic of the user equipment is a single application, or knowing that the UE is an M2M device, thereby not only implementing the route-optimized processing of data of the UE, reducing the system load of the gateway, but also establishing only one PDN connection for the UE, avoiding establishing a redundant PDN connection for the UE, and saving resources on the network side, meanwhile, the APN used by the PDN connection with the optimized routing or the APN used by the PDN connection with the normal routing is selected by the core management network element, the APN used by the PDN connection with the optimized routing does not need to be configured in the UE, the APN used by the PDN connection with the normal routing and the APN used by the PDN connection with the optimized routing do not need to be distinguished by the UE, and the processing of the UE is simplified.

Example six,

According to the method described in the first embodiment, this embodiment will be described in detail by taking an example in which the core management network element instructs the access-side network element to perform the route optimization processing in the Attach procedure. As shown in fig. 7, the specific process may be as follows:

601. and the UE sends an attachment request message or an update request message or a service request message to an access side network element of the access network.

Optionally, the attach request message or the update request message or the service request message may include indication information whether the UE is an M2M device, where specific processing of the indication information may be described in the first embodiment.

Optionally, the M2M group id may be included in the attach request message or the update request message or the service request message.

The update request in this step may be a tracking area update request message or a routing area update request message.

602. After receiving the attach request Message, the update request Message, or the service request Message, the access-side network element sends an initialization UE Message (Initial UE Message) to the core management network element, where the initialization UE Message includes the attach request Message, the update request Message, or the service request Message sent by the UE. Optionally, the initialization UE message carries an IP address with the access-side network element.

603. After receiving the attach request message, the update request message, or the service request message, the core management network element obtains the subscription data of the UE from the subscription database if the core management network element does not have valid subscription data of the UE.

604. If no default PDN connection is established for the UE, the core management network element selects a default APN, executes a GW selection function according to the APN, selects a GW used by the PDN connection, and then initiates a PDN connection establishment process to establish the PDN connection to the selected GW. The core management network element sends a create session request message to the GW. The GW returns a create session response message to the core management network element.

605. The core management element sends an initialization Context setup Request (initialization Context setup Request) message or a radio access bearer Assignment Request (RAB Assignment Request) message to the access side network element, and the access side network element may return an initialization Context setup Response (initialization Context setup Response) message or a radio access bearer Assignment Response (RAB Assignment Response) message to the core management element.

The core management network element decides whether to instruct the access side network element to execute the route optimization processing, and if the core management network element decides to instruct the access side network element to execute the route optimization processing, the initialized context establishment request or the radio access bearer allocation request message includes instruction information to instruct the access side network element to execute the route optimization processing. For specific decisions and indications, refer to the description in the first embodiment.

If the access side network element receives the indication information for executing the route optimization processing from the core management network element, the access side network element executes the route optimization processing after receiving the uplink data packet of the UE, and directly sends the uplink data packet to the IP network without sending the uplink data packet to the GW; if the access side network element does not receive the indication information for executing the route optimization processing from the core management network element, the access side network element receives the uplink data packet of the UE and then sends the uplink data packet to the GW or the access side network element analyzes the uplink data packet to obtain the filter of the uplink data packet, and the access side network element determines whether the uplink data packet executes the route optimization function or not according to the routing strategy configured in the access side network element and the filter of the uplink data packet, namely the data packet is directly sent to the IP network or sent to the IP network through the GW.

606. And the core management network element sends an attachment acceptance message or an update acceptance message or a service acceptance message to the UE.

In addition, it should be noted that, if the core management network element obtains information that the UE only allows to establish a single PDN connection, or the core management network element learns that the characteristic of the UE is a single application, or the core management network element learns that the UE is an M2M device, the core management network element rejects other PDN connection establishment requests after establishing a PDN connection for the UE, that is, the core management network element rejects the request of the UE after receiving the PDN connection request message or the PDP context activation request message sent by the UE, and returns the PDN connection rejection message or activates the PDP context rejection message to the UE. This ensures that only one PDN connection is established for the UE.

As can be seen from the above, in this embodiment, it is determined to instruct the access-side network element to perform the route optimization processing by knowing that the UE only allows to establish one PDN connection, or that the UE has a single application characteristic, or that the UE is an M2M device, so that the access-side network element can directly perform the route optimization processing after receiving the uplink data packet, which not only implements the route optimization processing of the data of the UE and reduces the system load of the gateway, but also simplifies the processing in the access-side network element, improves the performance of the access-side network element, and reduces the possibility of overloading the access-side network element, thereby increasing the user experience, and also avoids establishing a redundant PDN connection for the UE and saves the resource on the network side because only one PDN connection is established for the UE

Example seven,

The difference between this embodiment and the sixth embodiment is that, in the sixth embodiment, the core management network element indicates the access-side network element to perform the route optimization processing in the Attach procedure, but this embodiment will be described by taking as an example that the core management network element indicates the access-side network element to perform the route optimization processing in the PDN connection procedure requested by the UE or in the PDP context activation procedure or in the bearer establishment procedure initiated by the network side. As shown in fig. 8, the specific process may be as follows:

steps 701 to 703 are the same as steps 601 to 603 in the sixth embodiment, and will not be described in detail here.

704. The core management network element sends an attach accept message or an Update accept (Update Access) message to the UE.

705. And the UE sends a PDN connection request message or a PDP context activation request message to a core management network element.

706. The core management network element selects APN used by UE, executes GW selection function according to the APN, selects GW used by PDN connection, and then initiates a PDN connection establishment program to establish PDN connection to the selected GW. The core management network element sends a create session request message or a create PDP context request message to the GW. The GW returns a create session response message or a create PDP context response message to the core management network element.

707. The core management network element sends a Bearer Setup Request (Bearer Setup Request) message or a radio access Bearer Assignment Request (RAB Assignment Request) message to the access side network element, and the access side network element may return a Bearer Setup Response (Bearer Setup Response) message or a radio access Bearer Assignment Response (RAB Assignment Response) message to the core management network element.

The core management network element determines whether to instruct the access side network element to perform a route optimization process. And if the core management network element determines to indicate the access side network element to execute the route optimization processing, the bearer establishment request message or the radio access bearer allocation request message comprises indication information to indicate the access side network element to execute the route optimization processing. The specific determination method and the indication information are described in the first embodiment.

If the access side network element receives the indication information for executing the route optimization processing from the core management network element, the access side network element executes the route optimization processing after receiving an uplink data packet of the UE, and directly sends the uplink data packet to the IP network without sending the uplink data packet to the GW; if the access side network element does not receive the indication information for executing the route optimization processing from the core management network element, the access side network element receives the uplink data packet of the UE and then sends the uplink data packet to the GW or the access side network element analyzes the uplink data packet to obtain the filter of the uplink data packet, and the access side network element determines whether the uplink data packet executes the route optimization function according to the routing strategy configured in the access side network element and the filter of the uplink data packet, namely, the data packet is directly sent to the IP network or sent to the IP network through the GW.

708. The GW sends a Create Bearer Request (Create Bearer Request) message to the core management network element.

709. The processing of this step is the same as that of step 707, and will not be described in detail here

710. The core management network element returns a Create Bearer Response (Create Bearer Response) message to the GW.

It should be noted that, if the core management element obtains information that the UE only allows to establish a single PDN connection, or the core management element learns that the characteristic of the UE is a single application, or the core management element learns that the UE is an M2M device, the core management element rejects other PDN connection establishment requests after establishing a PDN connection for the UE, that is, the core management element rejects the request of the UE after receiving a PDN connection request message or an activate PDP context request message sent by the UE, and returns a PDN connection rejection message or activates a PDP context rejection message to the UE. This ensures that only one PDN connection is established for the UE.

It should be noted that there is no sequential relationship between the processing of the part a (i.e., steps 705 to 707, see the dashed box part in fig. 8) and the processing of the part B (i.e., steps 708 to 710, see the dashed box part in fig. 8) in fig. 8, and the two parts of processing are also independent, i.e., may not be processed in the same program.

As can be seen from the above, in this embodiment, it is determined to instruct the access-side network element to perform the route optimization processing by knowing that the UE only allows to establish one PDN connection, or that the characteristic of the UE is a single application, or that the UE is an M2M device, so that the access-side network element can directly perform the route optimization processing after receiving the uplink data packet, which not only implements the route optimization processing of the data of the UE and reduces the system load of the gateway, but also simplifies the processing in the access-side network element, improves the performance of the access-side network element, and reduces the possibility of overloading the access-side network element, thereby increasing the user experience, and also avoids establishing a redundant PDN connection for the UE and saves the resources on the network side because only one PDN connection is established for the UE.

Example eight,

In order to better implement the above method, the present invention further provides a core management network element accordingly, as shown in fig. 9, the core management network element includes a first obtaining unit 801 and a processing unit 802;

a first obtaining unit 801, configured to obtain information that a user equipment only allows establishing a single packet data network PDN connection, or obtain information that a characteristic of the user equipment is a single application, or obtain information that the user equipment is a machine-to-machine M2M device;

a processing unit 802, configured to perform route optimization for the user equipment according to the information that the user equipment only allows establishing a single packet data network PDN connection, or the information that the characteristic of the user equipment is a single application, or the information that the user equipment is an M2M device, acquired by the first acquiring unit 801.

The processing unit 802 may be specifically an establishing module;

and the establishing module is used for establishing a route optimized PDN connection for the user equipment according to the information that the user equipment only allows to establish a single packet data network PDN connection, or the information that the characteristic of the user equipment is a single application, or the information that the user equipment is an M2M device, which is acquired by the first acquiring unit.

The establishing module (or the processing unit 802) may include a first address obtaining subunit, a first requesting subunit, and a first receiving subunit;

a first address obtaining subunit, configured to obtain an IP address of an access side network element to which the UE is accessed after the information that the user equipment obtained by the first obtaining unit only allows establishment of a single packet data network PDN connection, or the information that the characteristic of the user equipment is a single application, or the information that the user equipment is an M2M device;

a first request subunit, configured to send a session creation request message or a PDP context creation request message to the access-side network element corresponding to the IP address acquired by the first address acquisition subunit;

the first receiving subunit is configured to receive a create session response message or a create PDP context response message returned by the access-side network element (i.e., the access-side network element that receives the create session request message or the create PDP context request message sent by the first requesting subunit).

Alternatively, the processing unit 802 may specifically be a route optimization indicating module;

and the route optimization indicating module indicates the access side network element to execute route optimization according to the information that the user equipment only allows to establish a single Packet Data Network (PDN) connection, or the information that the characteristic of the user equipment is a single application, or the information that the user equipment is an M2M device, acquired by the first acquiring unit.

The route optimization direction module (or the processing unit 802) may include a second address obtaining subunit, a second requesting subunit, and a second receiving subunit;

a second request subunit, configured to send an initialization context establishment request, a radio access bearer allocation request, or a bearer establishment request message to the access-side network element;

a second indication subunit, configured to include indication information in the initialization context establishment request, the radio access bearer allocation request, or the bearer establishment request message, where the indication information indicates the access-side network element to perform route optimization.

The first obtaining unit 801 may specifically be a data obtaining sub-module;

the data acquisition submodule is used for acquiring the subscription data or the group subscription data of the user equipment from the subscription database, and if the number of the PDN connections allowed to be used in the subscription data is 1, the data acquisition submodule acquires that the user equipment only allows to establish a single PDN connection; or, the subscription data acquisition unit is configured to acquire subscription data or group subscription data of the user equipment from a subscription database, and if the characteristic information in the subscription data is a single application, acquire that the characteristic of the user equipment is the single application; or, the apparatus is configured to acquire subscription data or group subscription data of the user equipment from the subscription database, where the subscription data includes information that the user equipment is M2M, and learn that the user equipment is M2M according to the information that the user equipment is M2M.

Alternatively, the first obtaining unit 801 may specifically be an identifier obtaining sub-module;

the identifier obtaining submodule is used for obtaining an M2M group identifier of the user equipment, and when the number of the PDN connections allowed to be used is obtained to be 1 according to the M2M group identifier, the user equipment is informed that only a single PDN connection of the packet data network is allowed to be established; or, the M2M group identifier is used to obtain the M2M group identifier of the user equipment, and when the characteristic information is obtained according to the M2M group identifier as a single application, it is known that the characteristic of the user equipment is the single application; or, the M2M group identifier is used to obtain the M2M group identifier of the ue, and if the M2M device information table includes the M2M group identifier, it is known that the ue is an M2M device; or, the receiving unit is configured to receive indication information, sent by the user equipment, indicating that the user equipment is an M2M device.

The core management network element may further include a second obtaining unit;

a second obtaining unit, configured to obtain any one or a combination of information that an access-side network element supports route optimization and information that allows a user equipment to use route optimization;

the processing unit 802 is further configured to perform route optimization for the user equipment according to any one or combination of the information that the access-side network element acquired by the second acquiring unit supports route optimization and the information that the user equipment is allowed to use route optimization, and the information that the user equipment acquired by the first acquiring unit 801 only allows establishing a single packet data network PDN connection, and any one of the information that the user equipment has a characteristic of a single application and the information that the user equipment is an M2M device, for example, establishing a route-optimized PDN connection for the user equipment or instructing the access-side network element to perform route optimization processing. That is, any one of the following (1), (2), and (3) may be used:

In order to ensure that only one PDN connection is established, the core management network element may further include a rejection unit;

a rejecting unit, configured to reject another PDN connection establishment request after the first obtaining unit 801 obtains information that the UE only allows establishing a single PDN connection, or obtains information that the UE has a single application, or obtains information that the UE is an M2M device, and the processing unit 802 determines to establish a PDN connection for the UE.

The core management network element may further include a receiving unit and an indicating unit;

a receiving unit, which receives an update request message or a service request message sent by user equipment;

an indicating unit, which indicates the UE to initiate an attach procedure if a route-optimized PDN connection is established for the UE and an access-side network element changes or an old PDN connection is a normal-routed PDN connection, and only a single PDN connection is allowed to be established according to the obtained information of the UE, or the information that the characteristic of the UE is a single application is obtained, or the information that the UE is M2M is obtained, and the route-optimized PDN connection is established for the UE;

the implementation of each unit above can be referred to in the method embodiments, and is not described herein again.

The core management network element may specifically include an MME, an SGSN, or a mobility management network element in a non-3GPP network.

Accordingly, an embodiment of the present invention further provides a communication system, including any core management network element provided in the embodiment of the present invention, which may specifically refer to the foregoing embodiment and will not be described herein again.

As can be seen from the above, the core management network element in this embodiment may determine to establish a route-optimized PDN connection for the UE by knowing that the UE only allows to establish one PDN connection, or that the UE has a single application characteristic, or that the UE is an M2M device, so that while implementing route optimization processing for data of the UE to reduce system load of a gateway, it is ensured that only one PDN connection is established for the UE, and occurrence of a situation of establishing a redundant PDN connection for the UE is avoided, thereby saving resources on a network side, and at the same time, it is not necessary to configure an APN used by the route-optimized PDN connection in the UE, and it is not necessary for the UE to be able to distinguish an APN used by a normally routed PDN connection from an APN used by the route-optimized PDN connection, thereby simplifying processing of the UE; or, the core management network element may also determine to instruct the access-side network element to perform the route optimization processing by knowing that the UE only allows to establish one PDN connection, or that the characteristic of the UE is a single application, or that the UE is an M2M device, so that the access-side network element may directly perform the route optimization processing after receiving the uplink packet, thereby not only realizing the route optimization processing of the data of the UE and reducing the system load of the gateway, but also avoiding establishing a redundant PDN connection for the UE and saving resources on the network side because only one PDN connection is established for the UE, and further, because the access-side network element does not need to perform the analysis of the uplink packet, the processing in the access-side network element may be simplified, the performance of the access-side network element may be improved, the possibility of overloading of the access-side network element may be reduced, and thereby the user experience may be increased.

Those skilled in the art will appreciate that all or part of the steps in the methods of the above embodiments may be implemented by associated hardware instructed by a program, which may be stored in a computer-readable storage medium, and the storage medium may include: read Only Memory (ROM), Random Access Memory (RAM), magnetic or optical disks, and the like.

The foregoing describes in detail a processing method, an apparatus and a communication system for route optimization according to embodiments of the present invention, and a specific example is applied in the present disclosure to explain the principle and the implementation of the present invention, and the description of the foregoing embodiments is only used to help understanding the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims

1. A processing method for route optimization, comprising:

performing routing optimization for the user equipment according to the acquired information that the user equipment only allows to establish a single packet data network PDN connection, or the information that the characteristic of the user equipment is single application, or the information that the user equipment is M2M equipment;

wherein the performing of the route optimization for the user equipment comprises: establishing a route optimized PDN connection for the user equipment; or, the access side network element is instructed to execute route optimization.

2. The method according to claim 1, wherein the establishing a route-optimized PDN connection for the user equipment is specifically:

acquiring an IP address of an access side network element accessed by the UE;

sending a request message for establishing a session or a request message for establishing a PDP context to an access side network element corresponding to the IP address;

and receiving a response message for establishing the session or a response message for establishing the PDP context returned by the network element at the access side.

3. The method of claim 1 or 2, wherein obtaining information that the ue is only allowed to establish a single PDN connection, or obtaining information that the ue is characterized as a single application, or obtaining information that the ue is an M2M device further comprises:

receiving an update request message or a service request message sent by user equipment;

the obtaining information that the user equipment only allows to establish a single PDN connection, or obtaining information that the characteristic of the user equipment is a single application, or obtaining information that the user equipment is an M2M device further includes:

and when the change of an access side network element or the old PDN connection is known to be the PDN connection of the normal route, and the routing optimization PDN connection is established for the UE according to the acquired information that the user equipment only allows to establish the single PDN connection, or the information that the characteristic of the user equipment is single application, or the information that the user equipment is M2M equipment, the user equipment is indicated to initiate an attachment process.

4. The method of claim 1, wherein the instructing the access side network element to perform the route optimization specifically includes:

the method comprises the steps that indication information is included in an initialization Context Setup Request Initial Context Setup Request, a radio access bearer Assignment Request RAB Assignment Request or a bearer Setup Request BeareSetup Request message sent to an access side network element, and the indication information indicates the access side network element to execute route optimization.

5. The method of claim 1, wherein the obtaining information that the ue is allowed to establish only a single PDN connection comprises:

acquiring subscription data of user equipment from a subscription database, and acquiring that the user equipment only allows to establish a single packet data network PDN connection if the number of PDN connections allowed to be used in the subscription data is 1; or,

and acquiring an M2M group identifier of the user equipment, and acquiring that the number of PDN connections allowed to be used is 1 according to the M2M group identifier, so that the user equipment is informed that only a single PDN connection of the packet data network is allowed to be established.

6. The method of claim 5, wherein the obtaining the number of PDN connections allowed to be used as 1 according to the M2M group identity comprises:

configuring a PDN connection number table in a core management network element; the core management network element inquires the PDN connection number table according to the M2M group identifier; if the number of the PDN connections identified by the M2M group in the PDN connection number table is 1, acquiring that the number of the PDN connections allowed to be used is 1; or,

acquiring M2M group subscription data from a subscription database according to the M2M group identifier core management network element; and if the M2M group subscription data contains information that the number of the PDN connections allowed to be used is 1, acquiring that the number of the PDN connections allowed to be used is 1.

7. The method of claim 1, wherein obtaining information that characterizes a single application of a user equipment comprises:

acquiring subscription data of user equipment from a subscription database, and acquiring that the characteristic of the user equipment is a single application if the characteristic information in the subscription data is the single application; or,

and acquiring the M2M group identifier of the user equipment, and acquiring the characteristic information as a single application according to the M2M group identifier to know that the characteristic of the user equipment is acquired as the single application.

8. The method of claim 7, wherein the obtaining the property information according to the M2M group identity as a single application comprises:

querying the characteristics of a preset M2M group according to the M2M group identification; learning characteristic information as a single application if the characteristic of the M2M group is a single application; or,

acquiring M2M group subscription data from a subscription database according to the M2M group identifier, and acquiring the characteristic information as a single application if the M2M group subscription data contains information that the characteristic is the single application.

9. The method of claim 1, wherein the obtaining information that the user equipment is an M2M device comprises:

acquiring subscription data of user equipment from a subscription database, wherein the subscription data comprises information that the user equipment is M2M, and acquiring that the user equipment is M2M equipment according to the information that the user equipment is M2M; or,

receiving indication information which is sent by user equipment and indicates that the user equipment is M2M equipment; or,

acquiring an M2M group identifier of user equipment, acquiring M2M group subscription data from a subscription database according to the M2M group identifier, and acquiring that the user equipment is M2M equipment according to information that the user equipment is M2M if the M2M group subscription data comprises the information that the user equipment is M2M.

10. The method of claim 1, further comprising:

acquiring any one or combination of information that an access side network element supports route optimization and information that user equipment is allowed to use route optimization;

and according to any one or combination of the information that the access side network element supports route optimization and the information that the user equipment is allowed to use the route optimization, and any one of the information that the user equipment is only allowed to establish a single Packet Data Network (PDN) connection, the information that the characteristic of the user equipment is a single application, and the information that the user equipment is an M2M device, establishing the route optimized PDN connection for the user equipment or instructing the access side network element to execute route optimization processing.

11. The method of claim 1, further comprising:

rejecting other PDN connection establishment requests.

12. A core management network element, comprising:

a processing unit, configured to perform, according to the information that the user equipment only allows establishment of a single packet data network PDN connection, or the information that the characteristic of the user equipment is a single application, or the information that the user equipment is an M2M device, route optimization for the user equipment;

13. The core managing network element of claim 12,

the processing unit is specifically configured to establish a route-optimized PDN connection for the user equipment according to the information that the user equipment acquired by the first acquiring unit only allows establishment of a single packet data network PDN connection, or the information that the user equipment has a single application characteristic, or the information that the user equipment is an M2M device.

14. The core management network element of claim 13, wherein the processing unit comprises:

and the first receiving subunit is configured to receive a session creation response message or a PDP context creation response message returned by the access-side network element.

15. The core managing network element of claim 12,

the processing unit is specifically configured to instruct, according to the information that the user equipment acquired by the first acquiring unit only allows establishment of a single packet data network PDN connection, or the information that the characteristic of the user equipment is a single application, or the information that the user equipment is an M2M device, the access-side network element to perform route optimization.

16. The core management network element of claim 15, wherein the processing unit comprises:

a second indication subunit, configured to include indication information in the initialization context establishment request, the radio access bearer allocation request, or the bearer establishment request message, where the indication information indicates an access-side network element to perform route optimization.

17. The core managing network element of claim 12,

the first obtaining unit is specifically configured to obtain subscription data or group subscription data of the user equipment from a subscription database, and if the number of PDN connections allowed to be used in the subscription data is 1, it is known that the user equipment only allows a single PDN connection to be established; or, the subscription data acquisition unit is configured to acquire subscription data or group subscription data of the user equipment from the subscription database, and if the characteristic information in the subscription data is a single application, acquire that the characteristic of the user equipment is the single application; or, the apparatus is configured to acquire subscription data or group subscription data of the user equipment from the subscription database, where the subscription data includes information that the user equipment is M2M, and learn that the user equipment is M2M according to the information that the user equipment is M2M.

18. The core managing network element of claim 12,

the first obtaining unit is specifically configured to obtain an M2M group identifier of the user equipment, and when the number of PDN connections allowed to be used is obtained to be 1 according to the M2M group identifier, it is known that the user equipment only allows a single PDN connection to be established; or, the M2M group identifier is used to obtain the M2M group identifier of the user equipment, and when the characteristic information is obtained according to the M2M group as a single application, it is known that the characteristic of the user equipment is the single application; or, the M2M group identifier is used to obtain the M2M group identifier of the ue, and if the M2M group identifier is included in the M2M device information table, it is known that the ue is an M2M device; or, the receiving unit is configured to receive indication information, sent by the user equipment, indicating that the user equipment is an M2M device.

19. The core management network element of claim 12, further comprising a second obtaining unit;

a second obtaining unit, configured to obtain at least one of information that an access-side network element supports route optimization and information that allows a user equipment to use route optimization;

the processing unit is further configured to perform route optimization for the user equipment according to at least one of information that the access-side network element acquired by the second acquiring unit supports route optimization and information that the user equipment is allowed to use route optimization, and any one of information that the user equipment only allows establishing a single packet data network PDN connection and information that the user equipment has a characteristic of a single application and information that the user equipment is an M2M device acquired by the first acquiring unit.

20. The core management network element of claim 12, further comprising a rejection unit;

a rejecting unit, configured to reject other PDN connection establishment requests after the processing unit performs route optimization for the user equipment.

21. The core management network element of claim 12, further comprising a receiving unit and an indicating unit;

a receiving unit, configured to receive an update request message or a service request message sent by a user equipment;

and an indicating unit, configured to indicate, if a route-optimized PDN connection is established for the UE, and an access-side network element changes or an old PDN connection is a normal-routed PDN connection, the user equipment to initiate an attach procedure when only a single PDN connection is allowed to be established according to the information that is obtained by the first obtaining unit, or information that is a single application is obtained by the user equipment, or information that is an M2M device is obtained by the user equipment to establish the route-optimized PDN connection for the UE.

22. A communication system, characterized in that it comprises a core management network element according to any one of claims 12 to 21.