WO2009089790A1

WO2009089790A1 - Method for acquiring bearer service type and switching between bearer networks for terminals

Info

Publication number: WO2009089790A1
Application number: PCT/CN2009/070084
Authority: WO
Inventors: Ying Hu; Jinguo Zhu; Zaifeng Zong; Minya Ye
Original assignee: Zte Corporation
Priority date: 2008-01-09
Filing date: 2009-01-08
Publication date: 2009-07-23
Also published as: CN101217794A; CN101217794B

Abstract

The invention presents a method for acquiring bearer service type and switching between bearer networks for terminals. When establishing bearer, Policy Charging Rule Function PCRF determines the bearer service type information according to the application information provided by the application server, and transmits the said bearer service type information to the bearer network. With the technical solution of the present invention, the bearer network is able to acquire the bearer service type information when establishing bearer, and perform handover quickly and accurately when terminals need to switch between bearer networks.

Description

Knowing the type of bearer service and the method for the terminal to switch between bearer networks

Technical field

The present invention relates to a mobile communication system, and more particularly to a method for how a bearer network learns a bearer service type in an evolved packet domain system, and a method for the terminal to switch between bearer networks.

Background technique

With the global emergence of the World Interoperability for Microwave Access (Wimax), the third generation of mobile communication systems must maintain their strong competitiveness in the field of mobile communications, and must improve their network performance and reduce Network construction and operating costs. Therefore, the 3rd Generation Partnership Project (3GPP) standardization working group is currently working on the Packet Switch Core (PS Core) and the full mobile communication system radio access network ( The evolution of the Universal Mobile Telecommunication System Radio Access Network (UTRAN), the subject of this research is called System Architecture Evolution (SAE), which aims to make the evolved PS Core (Evolved PS Core, EPC for short) higher. Transmission rate, shorter transmission delay, optimized packet, and support for evolved UTRAN (Evolved UTRAN, E-UTRAN for short), GSM EDGE radio access network (GSMRAN), where GSM is Global System Abbreviation for Mobile Communications, the global mobile communication system. EDGE is the abbreviation of Enhanced Data Rate for GSM Evolution, namely enhanced data rate GSM evolution technology), UTRAN, Wireless Local Area Network (WLAN) and other non-3GPP Connection Mobility management between networks. This evolved mobile communication system is called the Evolved Packet System (EPS). The basic architecture is shown in Figure 1. It mainly includes the following network elements and related concepts:

E-UTRAN: An evolved radio access network that provides higher uplink and downlink rates, lower transmission delays, and more reliable wireless transmission. The network element included in the E-UTRAN is an evolved Node B (eNodeB), which provides radio resources for terminal access.

Mobility Management Entity (MME): Control plane functional entity, a server that temporarily stores user data, and is responsible for managing and storing the user's mobile terminal (or Jane) User equipment (referred to as UE) context (such as UE/user ID, mobility management status, user security parameters, etc.), assigns a temporary identifier to the user, and is responsible for the user when the UE is camped in the tracking area or the network. Perform authentication; process all non-access stratum messages between the MME and the UE. The bearer identifier is allocated by the MME and saved in the MME;

Home Subscriber Server (HSS): Permanently stores user subscription data and provides authentication for users;

Serving Gateway ( Serving GW or S-GW): It is a user plane entity responsible for user plane data routing processing and terminating downlink data of UEs in idle state. The bearer context of the UE, such as the Internet Protocol (IP) bearer service parameter and the internal routing information of the network, is an anchor point of the internal user plane of the 3GPP system;

The Packet Data Network Gateway (PDN GW or P-GW) is responsible for the gateway function of the UE accessing the PDN.

Physically, Serving GW and PDN GW may be one.

The General Packet Radio Service (GPRS) Service Supporting Node (SGSN) is a control network element of the GPRS network.

In a mobile communication system, traffic is provided by a bearer. The EPS bearer refers to a channel from the terminal to the PDN GW. The UE and the PDN GW can use the channel to transmit uplink and downlink data of a specific Quality of Service (QoS). Different services require different bearers to transmit because they require different QoS guarantees. In an EPS network, bearer QoS control is implemented through a Policy Control and Charging (PCC) architecture. During the establishment of the PCC architecture bearer, the PCC policy and the Charging Rule Function (PCRF) obtain the application information of the service from the Application Function (AF) to generate the accounting and QoS. Rules, and the rules are issued to the gateway (Gateway, GW for short) node, the gateway node (PDG GW in the WLAN, PDN GW in the EPS network). Policy and Charging Enforcement Function According to these QoS information, it is decided whether to create a new bearer that satisfies the QoS or modify the original bearer to meet the QoS requirements. The process is shown in Figure 2: 201. The application server AF provides service information to the PCRF. Application information such as media type is included in this information. In this step, the application server AF can sign the bearer layer event according to the service requirement, and whether the PCRF needs to notify itself;

202. The PCRF receives the message sent by the application server, saves the service information, and responds to the application server.

203. The PCRF authenticates the service information, and performs a decision according to the service information, and generates a PCC rule. The PCC rule includes only accounting and policy control related information, and does not include service information.

204. The PCRF sends a PCC rule message to the GW (PCEF) in the bearer network. Currently, the message mainly includes charging and policy control related information, and does not include service information.

205, GW (PCEF) execution policy, according to the QoS information in the PCC rule, determining whether to create a new bearer that satisfies the service QoS requirement, or modify the original bearer to meet the QoS requirement;

206: The GW (PCEF) initiates a signaling interaction related to the bearer network bearer. If there is no bearer in the existing bearer of the PDN of the current service that can satisfy the QoS requirement of the service, the bearer network starts to create a new bearer, otherwise the existing bearer is modified to meet the service QoS requirement;

207. The bearer network creates or modifies the bearer. GW (PCEF) receives the response message;

208. The GW (PCEF) sends a response message to the PCRF, where the message tells the PCF that the PCC rule delivered by the PCRF is accepted or rejected by the bearer network.

209. If the application server AF sends the application information to the PCRF at 201, and signs the bearer layer event notification, it needs to perform 209 and 210, otherwise 209 and 210 are not needed. The PCRF sends a message to the application server AF to notify the bearer to create or modify the completion;

210. The application server AF sends a response message to the PCRF.

Let's consider the problem that needs to be faced when deploying an EPS system. When the EPS system is deployed, the situation shown in Figure 3 will appear. The EPS network only covers a part of the area, and the coverage of the UMTS/GSM network is relatively large, so that when the user is in the area covered by the SAE and UMTS/GSM simultaneously or in the edge area (such as voice call, browsing webpage, etc.), because of the signal Strong and weak, the terminal needs to switch from the EPS system to the UMTS/GSM system to ensure business continuity.

In the UMTS/GSM network, for the voice service, it is mainly provided through the Circuit Switched (CS) domain, so when the above switching occurs, if the user performs It is a voice service. The EPS network needs to switch the service to the CS domain of UMTS/GSM. For other services, it can switch to the Packet Switch (PS) domain of UMTS/GSM. Therefore, for an EPS network, it is necessary to distinguish whether the bearer is a voice service. However, in the current technology, the EPS network only knows the QoS parameter information of the bearer, and does not know the specific service type transmitted by the bearer. Therefore, the prior art cannot implement the handover from the EPS system to the UMTS/GSM system.

The QoS class identifier (QCI for short) is a quality of service class identifier and is a parameter in the PCC rule. In the prior art, the QCI is a value, and the current value is 1-9, which is used to identify a specific set of parameters in the bearer network QoS except for the bitrate. The QCI is transmitted in the bearer network to represent the network node. Specific bearer layer parameters configured by the operator. At present, QCI only has QoS meaning, and does not establish an inevitable relationship with the service type.

For example, in the EPS network, in addition to the bit rate, other QoS parameters are transmitted between nodes by using QCI, which are used to represent specific bearer layer parameters of nodes (such as eNodeB), and each QCI value is a resource type (transfer rate has / No guarantee), there is a 1:1 mapping between the packet delay time and the packet loss rate. A value of 2 indicates that the QCI is guaranteed, the packet delay time is 50 ms, and the packet loss rate is medium. The bearer with such quality of service can carry the IP voice call service, but there is no provision that other services cannot use such bearer. .

Summary of the invention

The present invention provides a method for obtaining a bearer service type and a handover between a bearer network. The bearer network can learn the bearer service type information when the bearer is established, and complete the handover quickly and accurately when the terminal needs to switch between the bearer networks. .

The technical solution of the present invention is a method for the bearer network to learn the bearer service type, including: when the bearer is established, the policy and charging rule function PCRF determines the bearer service type information according to the application information provided by the application server, and The bearer service type information is delivered to the bearer network.

Further, the PCRF transmits the bearer service type information to a gateway of the network in a message containing a policy control and charging rule, where the gateway carrying the network carries the service The type information is included in the bearer-related message and is passed to the network element in the bearer network.

Further, the type of service carried is a type of service type indication information;

The service type information is implemented in one of the following ways:

Add a parameter indicating the type of the service; or set the service quality category identifier to a specific value to indicate the bearer service type.

Further, the bearer network is an evolved packet domain system EPS network, and/or a universal mobile communication system/global mobile communication system UMTS/GSM network.

Further, when the bearer network is an EPS network, when the PCRF sends a policy control and charging rule message to the packet data network gateway, the bearer service type information is carried, and the packet data network gateway sends a create bearer or a modified bearer to the serving gateway. The message carries the bearer service type information, and the service gateway forwards the message for creating or modifying the bearer to the mobility management entity.

And the MME, where the bearer service type information is still carried, the MME, after receiving the message of creating the bearer or modifying the bearer, assigning the bearer identifier, and storing the association information of the bearer identifier and the bearer service type information.

Further, when the bearer network is an EPS network, the PCRF carries the bearer service type information when the service quality rule message is sent to the serving gateway, and the service gateway sends the bearer to the MME when the message is created or modified. After the MME receives the message of creating a bearer or a modified bearer, the MME allocates a bearer identifier, and saves the association information of the bearer identifier and the bearer service type information.

Further, when the eNodeB needs to learn the bearer service type information, the MME sends the bearer service type information to the eNodeB in the create bearer request message.

Further, when the handover is controlled by adding a handover coordination and interconnection module, the MME transmits the bearer service type information to the handover coordination and interconnection module.

Further, during the handover process of the terminal from the EPS to the UMTS/GSM, the MME first performs packet switching PS handover to the UMTS/GSM for all EPS bearers, and then performs the circuit switched CS handover of the voice service in the UMTS/GSM. When performing the PS handover, the MME indicates the bearer service type information of all bearers that need to be handed over to the general packet radio service support node SGSN, or only the bearer service type information of the bearer that needs to perform CS handover to the SGSN. Or only the bearer service type information of the bearer that does not need to perform CS handover is indicated to the SGSN.

The invention also provides a method for a terminal to switch between bearer networks, including:

When the evolved packet domain system EPS network establishes a bearer of the service, the policy and charging rule function PCRF determines the bearer service type and transmits the network element to the EPS network according to the application information provided by the application server;

Before the UE switches from the EPS network to the universal mobile communication system/global mobile communication system UMTS/GSM network, the network element of the EPS network transmits the bearer service type information to the handover control module in the bearer network;

When the UE switches from the EPS network to the UMTS/GSM network, the handover control module initiates a circuit switched CS handover and/or a packet switched PS handover according to the learned bearer service type information, thereby completing the handover.

Further, the handover control module in the bearer network is a mobility management entity MME, and the MME obtains the bearer service type information when establishing a bearer;

When the UE is switched from the EPS network to the UMTS/GSM network, the MME distinguishes the bearer according to the learned bearer service type information, initiates a CS handover to the VoIP service, and initiates a PS handover to the SGSN for the service other than the voice service. .

Further, the handover control module in the bearer network is a handover coordination and interconnection module, and the MME obtains the bearer service type information when establishing a bearer;

Before the UE switches from the EPS network to the UMTS/GSM network, the MME transmits the bearer service type information of the bearer to the handover coordination and interconnection module;

When the UE is switched from the EPS network to the UMTS/GSM network, the handover coordination and interconnection module differentiates the bearers according to the learned bearer service type, and initiates a CS handover to the VoIP service, and the service other than the voice service is sent to the SGSN. Initiate a PS switch.

Further, the handover control module in the bearer network is a mobility management entity and a general packet radio service support node, and the MME obtains the bearer service type information when the bearer is established;

When the UE switches from the EPS network to the UMTS/GSM network, the MME switches all the bearers to the PS domain of the UMTS/GSM, and transmits all the bearer service type letters when performing the PS handover. Indicates to the SGSN, or only the bearer service type information of the bearer that needs to perform the CS handover to the SGSN, or only the bearer service type information of the bearer that does not need to perform the CS handover to the SGSN; the SGSN according to the indication information It is determined whether there is a voice service, and when there is a voice service, a CS handover is initiated to the MSC.

In summary, the present invention provides a method for obtaining a bearer service type and a terminal to perform handover between bearer networks, and the method for obtaining a bearer service type according to the present invention can learn the bearer service type, and subsequent operations such as the terminal When switching between networks, the bearer network can accurately switch according to the type of bearer service.

BRIEF abstract

Figure 1 is a basic network structure diagram of the EPS system;

2 is a process in which an existing PCC framework sends QoS and charging information to a bearer network and creates a bearer;

Figure 3 is a schematic diagram of a deployment of an EPS network;

4 is a flow of a service type generated by the method of the present invention and transmitted to a bearer network; FIG. 5a is an embodiment of the present invention in an EPS system;

Figure 5b and Figure 5c are schematic diagrams of the architecture of an implementation for switching from an EPS network to a UMTS/GSM network. Preferred embodiment of the invention

The present invention provides a method for obtaining a bearer service type and a terminal to perform handover between bearer networks. When a bearer is established, the PCRF transmits the bearer service type information to the bearer network, and the bearer network quickly and accurately obtains the bearer service type information. The switching of the user equipment between the bearer networks is completed.

The invention is described in detail below with reference to the accompanying drawings. Although a logical order is shown in the figures, in some cases, the steps may be performed differently than shown or described herein.

FIG. 3 is a schematic diagram of deployment of an EPS network, and is also an application implementation scenario of the present invention in an EPS network. There are only two cases in the figure: The first one, the EPS network coverage part In the area, the area with EPS network has UMTS/GSM network; Second, the coverage of EPS network and UMTS/GSM network are different and partially overlap. However, the present invention is applicable to various situations in which the coverage of the EPS network and the UMTS/GSM network are completely overlapped, partially overlapped, and partially crossed, and the switching due to various reasons is also applicable.

FIG. 4 is a flow chart of a service type generated by the present invention and transmitted to a bearer network. As shown in Figure 4:

401. The application server AF provides application information of the service to the PCRF, where the media type information is included in the information;

402. The PCRF receives the message sent by the application server, saves the service information, and sends an AF response to the application server.

403. The PCRF performs a PCC decision according to application information of the service, and generates a message including a PCC rule, where the message including the PCC rule includes not only charging and policy control related information, but also a bearer generated according to application information such as a media type of the service. Business type information.

The bearer service type information can be implemented in the following two ways:

(1) By adding a parameter method; for example, a parameter "service type" is added to the policy control and charging rule message sent by the PCRF to the PDN GW to indicate the bearer service type information, and the PCRF carries the service through the parameter. The type information is passed to the PDN GW. This new parameter can be included in the PCC rules; it can also be included in the PCC rules and only included in messages containing PCC rules.

If the value of the QCI is 2, the value of the QCI is 2, which means that the service type of the bearer is a voice call and is only a voice call. The QCI value is 1 Indicates that the type of business carried is and is only a game.

404, the PCRF sends a message containing the PCC rule to the gateway GW (PCEF) in the bearer network, where the message includes the bearer service type information, and the bearer service type information is expressed and transmitted by using one of the methods 403;

405. The gateway GW (PCEF) executes a policy, and according to the QoS information in the PCC rule, determines whether to create a new bearer that satisfies the service QoS requirement, or modify the original bearer to meet the QoS requirement;

406. The gateway GW (PCEF) sends a bearer or a modified bearer message to the bearer network, where the message carries the bearer service type information, and the method for indicating and transmitting the bearer service type information may be used as 403. One of the two methods described.

The above methods of representing and transmitting bearer service type information are not limited to the two methods listed.

The invention will be further illustrated by an application example below:

Figure 5a is an application example of the present invention in an EPS network. This process is used to create a dedicated EPS bearer that users need to access for service in the EPS network. For example, a user accesses a voice call through an EPS network, and the process is used to create a dedicated EPS bearer that carries a voice media stream.

Before the creation of the dedicated bearer shown in Figure 5a, there are some prerequisite operations and conditions to be met between the user and the network, ensuring that the signaling interaction between the UE and the application server and the bearer network is completed, and the bearer is started. For example, the user has the following preconditions and conditions for making a voice call:

When the user's mobile terminal is connected in the EPS network, the voice call can be provided through the IMS (IP Multimedia Core Network Subsystem, IMS for short), and the various call control function modules in the IMS are the application server AF. In this case, the voice call can be enhanced by the Mobile Switching Center (MSC) (which can support the voice service when accessing through the EPS network, when the voice call is controlled by the CS domain, and the enhanced MSC is used. The application server (AF) provides; or the MSC enhancement mode, for example, the manner in which the MSC modification needs to be implemented by one or more newly added network elements, the newly added network element and/or The MSC serves as the application server AF. The user makes a voice call, and the UE and the application server AF have already performed signaling interaction, and the network starts to establish a dedicated bearer for the voice call service to carry the voice media stream.

501: The application server (for example, an IMS application server or an enhanced MSC, or another service application server) sends application/service information (Application/Service info) to the PCRF, and the message includes a media type information field (Media-Type). Values are: AUDIO (0) for voice, VIDEO (1) for video, etc. In the message, the application server can tell the PCRF bearer layer that the event (such as the bearer creation is successful) needs to notify itself. In the process shown in FIG. 5a, it is assumed that the application server needs the PCRF to notify the bearer layer of the event;

502: The PCRF receives the service information sent by the application server, saves the service information, and sends a response message to the application server. 503: The PCRF generates the bearer service type information according to the application information, such as the media type in the message received from the application server, generates a PCC rule, and sends a message containing the PCC rule to the PDN GW, where the message includes the bearer service type information. The bearer service type information may be represented by a new parameter such as "service type", or may be represented by a specific value of the QCI.

504: After receiving the policy and charging control rule message, the PDN GW decides to create a new bearer. When a new bearer is created, the PDN GW sends a Create Dedicated Bearer message to the Serving GW, adding a new parameter such as "Service Type" to the message to continue to deliver the received bearer service type information or assign a QCI specific value to indicate the service type. If the PDN GW needs to know the bearer service type information, it needs to understand the new bearer service type information transfer mode and save the related information. Otherwise, the PDN GW only needs to transmit the bearer service type information to the Serving GW, which does not need to be understood and saved.

505: The Serving GW receives the PDN GW to create a dedicated bearer message, and sends a message to the MME to create a dedicated bearer. The message continues to carry new parameters such as “service type” or a QCI specific value to indicate the bearer service type. If the Serving GW needs to know the bearer service type information, it needs to understand the new bearer service type information transfer mode and save the related information. Otherwise, the Serving GW only needs to pass the bearer service type information to the MME, which does not need to be understood and saved.

506: The MME receives the created dedicated bearer message of the Serving GW, allocates a bearer identifier, associates the bearer identifier with the service type information, and saves, so that the MME knows the type of the bearer service. The MME then sends a Create Bearer Request message to the eNodeB. Currently, the bearer identifier and QCI are carried in this message, and the eNodeB saves the two information. If the eNodeB needs to know the bearer service type information, the MME needs to pass the newly added parameters, such as the "service type", to the eNobeB. The eNobeB needs to understand and save the newly added service type. The information field can be associated with the value of the QCI and the type of service carried.

507: eNobeB and UE interact to establish wireless 7-load.

508: The radio bearer is established, and the eNobeB sends a bearer setup response message to the MME.

509: After receiving the bearer setup response message, the MME sends a dedicated bearer setup response message to the Serving GW, where the bearer identifier is carried in the message. 510: The Serving GW receives the dedicated bearer setup response message. If the service type information needs to be carried, the bearer identifier is associated with the service type information already known by the 505 and saved. Otherwise, only the bearer identifier may be saved. The Serving GW sends a dedicated bearer setup response message to the PDN GW.

511: After receiving the dedicated bearer setup response message, if the PDN GW needs to carry the service type information, the bearer identifier is associated with the service type information already known by the 504 and saved. Otherwise, only the bearer identifier may be saved. The PDN GW sends a response message to the PCRF.

512: The PCRF receives the providing response message, and sends a bearer event notification message to the application server, where the application server knows whether the bearer is successfully created.

513: The application server sends a response message to the PCRF, and the creation of the bearer process ends.

The case where the PDN GW has the PCEF function and the Qos information can be transferred between the PDN GW and the Serving GW is given in FIG. 5 and its description. In the case that the QoS information cannot be transmitted between the PDN GW and the Serving GW, the Serving GW completes the bearer binding function in the PCEF. In this case, the process of determining the bearer service type information of the bearer network is basically the same as the above process, mainly having the following differences. :

The PCRF generates bearer service type information according to application information such as media type in the message received from the application server, and generates a PCC rule and a Qos rule (the Qos rule is a part related to Qos in the PCC rule), and the PCRF is sent to the PDN GW and the Serving GW. The message containing the PCC rule and the QoS rule is sent separately, and the message sent by the PCRF to the Serving GW includes the bearer service type information. At this time, the bearer service type information may be represented by a new parameter such as "service type", or may be represented by a specific value of the QCI.

After receiving the message including the QoS rule, the Serving GW determines that a new bearer needs to be created, and sends a message to the MME to create a dedicated bearer. The message continues to carry new parameters such as "service type" or assign a specific value to the QCI to indicate the bearer service type. .

Figures 5b and 5c are respectively schematic diagrams of the implementation of two types of implementations for switching a UMTS/GSM network from an EPS network. The upper part of the dotted line in the figure indicates the UE accesses and related network elements in the EPS network, and the lower part of the dotted line indicates the UE accesses in the GSM/UMTS network (the UE in the figure indicates the UE in the GSM/UMTS network) and related network elements. . When the UE accesses the EPS network, the service may be voice. Calling and browsing web services, both types of services are accessed and provided through the EPS network. When the UE switches to the GSM/UMTS network, the voice calls are provided through the CS domain and controlled by network elements such as MSC/VLR; Services such as web pages are provided through the PS domain and are controlled by SGSN and the like.

There are three types of solutions for switching from EPS networks to UMTS/GSM networks:

In the first type, the MME controls the handover, and the MME is responsible for initiating the CS and PS handover. When both the CS handover and the PS handover are performed, the MME is responsible for coordinating the CS and PS handovers simultaneously starting and completing, as shown in FIG. 5b. In this type of scheme, the MME is configured as a bearer that has been established by the UE, and the bearer may have one or more bearers that have been established by the MME. The MME distinguishes the bearer service type according to the information of each bearer service type obtained by using the present invention. When the voice service is of the type, the MME is responsible for initiating a CS handover to the MSC. When the bearer service type has services other than the voice service, the MME initiates a PS handover to the SGSN, and coordinates the two. The switching is proceeding.

The second category is to add a handover coordination and interconnection module to initiate CS handover and PS handover. When there are both CS handover and PS handover, the handover coordination and interconnection module is responsible for coordinating the start and completion of CS and PS handover. The MME simply sends the handover related information to the handover coordination and interconnection module, as shown in Figure 5c. In this type of scheme, the MME obtains the bearer service type information by using the present invention, and indicates the bearer service type information to the handover coordination and interconnection module when the handover is required, and the handover coordination and interconnection module learns the bearer service according to the information sent by the MME. The type is responsible for initiating a CS handover to the MSC, and initiating a PS handover to the SGSN for services other than voice, and coordinating the progress of the two handovers.

The third type is that the bearer of all services first performs PS handover, and the MME first switches all services from the EPS network to the UMTS/GSM network; then in the UMTS/GSM network, the SGSN switches the bearer switched to the IP voice call to UMTS/GSM CS. In this type of scheme, when the EPS network is switched to the UMTS/GSM network, the MME needs to indicate the bearer service type information of all the bearers to be switched obtained by the present invention to the SGSN of the UMTS/GSM network, the UMTS/GSM network. The SGSN determines whether it needs to switch to UMTS/GSM CS again according to the bearer service type information, that is, when the service type information includes voice service, it needs to switch to UMTS/GSM CS again. The MME may also indicate the bearer service type information of the bearer that needs to perform CS handover to the SGSN, or only the bearer that does not need to perform CS handover, when the PS network is switched to the UMTS/GSM network. The bearer service type information is indicated to the SGSN, and the SGSN can determine whether the CS switch needs to be performed according to the indication information. When there is voice service in these indication information, the SGSN initiates a CS handover to the MSC.

The MME, the handover coordination and interconnection module, and the SGSN in the above embodiments may be collectively referred to as a handover control module.

The MSC and SGSN in the drawings and the above embodiments may be network elements of various variations and names having the above-described functions, and both MSC and SGSN representatives are used in the present invention.

The process of initiating a CS handover or PS handover according to the service type information in the above manner may be referred to the relevant standards.

In summary, according to the present invention, in the bearer establishment process, the bearer network can obtain bearer service type information. Therefore, corresponding operations and processes can be performed according to the bearer service type information during subsequent processing. At least the MME can know the bearer service type information in the EPS system, so as to ensure that the UE can correctly process in various situations and implementation methods when the UE switches from the EPS network to the GSM/UMS network.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

It is a matter of course that the invention may be embodied in various other forms and modifications without departing from the spirit and scope of the invention.

Industrial applicability

With the technical solution of the present invention, the bearer network can learn the bearer service type information. When subsequent operations, such as the user switching between networks, the bearer network can accurately switch according to the bearer service type information.

Claims

Claim

A method for a bearer network to learn a type of bearer service, characterized in that:

When the bearer is established, the policy and charging rule function PCRF determines the bearer service type information according to the application information provided by the application server, and transmits the bearer service type information to the bearer network.

2. The method of claim 1 wherein:

Transmitting, by the PCRF, the bearer service type information to a gateway of the network in a message containing a policy control and charging rule, where the gateway of the network carrying the bearer service type information is included in the bearer-related The message is passed to the network element in the bearer network.

3. The method of claim 2, wherein:

The bearer service type is bearer service type indication information;

The service type information is implemented in one of the following ways:

4. The method of claim 2, wherein:

The bearer network is an evolved packet domain system EPS network, and/or a universal mobile communication system / a global mobile communication system UMTS/GSM network.

5. The method of claim 4 wherein:

When the bearer network is an EPS network, the PCRF carries the bearer service type information when sending the policy control and charging rule message to the packet data network gateway, and the packet data network gateway sends a message for creating or modifying the bearer to the serving gateway. Carrying the bearer service type information, the service gateway forwarding the message for creating a bearer or modifying a bearer to a mobility management entity (MME), where the bearer service type information is still carried, and the MME receives the created bearer or modified The bearer identifier is allocated after the bearer message, and the association information of the bearer identifier and the bearer service type information is saved. The method of claim 4 wherein: When the bearer network is an EPS network, the PCRF carries the bearer service type information when the service quality rule message is sent to the serving gateway, and the service gateway sends the bearer service type information when the message is sent to the MME. After receiving the message of creating a bearer or modifying a bearer, the MME allocates a bearer identifier, and saves association information between the bearer identifier and the bearer service type information.

7. The method of claim 5 or 6, wherein:

When the eNodeB needs to learn the bearer service type information, the MME sends the bearer service type information to the eNodeB in the create bearer request message.

8. The method of claim 5 or 6, wherein:

When the handover is controlled by adding a handover coordination and interconnection module, the MME transmits the bearer service type information to the handover coordination and interconnection module.

9. The method of claim 5 or 6, wherein:

During the handover process of the terminal from EPS to UMTS/GSM, the MME performs packet switching PS handover to UMTS/GSM for all EPS bearers, and then performs circuit switched CS handover of voice services in UMTS/GSM, the MME is proceeding. When the PS is switched, the bearer service type information of all bearers that need to be handed over is indicated to the general packet radio service support node SGSN, or only the bearer service type information of the bearer that needs to perform CS handover is indicated to the SGSN, or only The bearer service type information of the bearer performing the CS handover is indicated to the SGSN.

10. A method for a terminal to switch between bearer networks, characterized in that:

Policy and charging rules function when establishing a bearer for a service in an evolved packet domain system EPS network

The PCRF determines the bearer service type and transmits the network element to the EPS network according to the application information provided by the application server;

When the UE switches from the EPS network to the UMTS/GSM network, the handover control module initiates a circuit switched CS handover and/or a packet switched PS handover according to the learned bearer service type information. Then complete the switch.

11. The method of claim 10 wherein:

The handover control module in the bearer network is a mobility management entity MME, and the MME obtains the bearer service type information when the bearer is established;

12. The method of claim 10 wherein:

The handover control module in the bearer network is a handover coordination and interconnection module, and the MME obtains the bearer service type information when the bearer is established;

13. The method of claim 10 wherein:

The handover control module in the bearer network is a mobility management entity and a general packet radio service support node, and the MME obtains the bearer service type information when establishing a bearer;

When the UE switches from the EPS network to the UMTS/GSM network, the MME switches all bearers to the PS domain of UMTS/GSM, and indicates the bearer service type information of all bearers to the SGSN when performing PS handover, or only needs to The bearer service type information of the bearer that performs the CS handover is indicated to the SGSN, or only the bearer service type information of the bearer that does not need to perform the CS handover is indicated to the SGSN; the SGSN determines whether there is a voice service according to the indication information, and has voice In the case of service, a CS handover is initiated to the MSC.