WO2011127657A1

WO2011127657A1 - Method for circuit switched fallback and mobile management entity

Info

Publication number: WO2011127657A1
Application number: PCT/CN2010/071774
Authority: WO
Inventors: 于益俊; 袁立平; 陆峰
Original assignee: 华为技术有限公司
Priority date: 2010-04-14
Filing date: 2010-04-14
Publication date: 2011-10-20
Also published as: CN102342155B; CN102342155A

Abstract

A method for Circuit Switched Fallback (CSFB) and a mobile management entity are provided. The method includes: the mobile management entity receives a short message sent from a user equipment (101); if the CSFB type of the user equipment is Gs CSFB, the mobile management entity sends a message including a CSFB indication to an evolved Node B to initiate the user equipment to return to the traditional network (102). The method for CSFB provided by the embodiments of the present invention does not need updating a mass of Mobile Switch Center/Visitor Location Register (MSC/VLR) equipments in the present network, thus reducing the cost of the CSFB scheme.

Description

Method for returning traditional network from circuit switched domain service and mobile management network element

The embodiments of the present invention relate to the field of communications technologies, and in particular, to a method for returning a circuit switched domain service to a traditional network and a mobility management network element. Background technique

General packet radio service (General Packet Radio Service; abbreviation: GPRS) / Universal Mobile Telecommunications System (Universal Mobile Telecommunications System; abbreviation: UMTS) is a third Generation Partnership Ge ^{1 j (The 3rd Generation Partnership Project} ; abbreviation: 3GPP) A mobile communication network defined by the organization, including a Radio Access Network (RAN) and a Core Network (C: Network). The CN is logically divided into a Circuit Switched Domain (CS) domain and a Packet Switched Domain (PS) domain. The CS domain mainly handles voice services, and the PS domain mainly handles packet services. The signaling plane control entity of the CS domain is a Mobile Switch Center (MSC)/Visitor Location Register (VLR), and the signaling plane control entity of the PS domain is a serving GPRS support node (Serving) GPRS Support Node; Abbreviation: SGSN), SGSN and MSC/VLR can be connected through Gs interface.

In order to meet the challenges of wireless broadband technology and maintain the leading edge of 3GPP networks, 3GPP has developed a Long Term Evolution (LTE) program and defined a new mobile communication network architecture under the guidance of the evolution plan. Architecture and current GPRS/UMTS is flatter and only retains the packet domain, so it can be called an Evolved Packet System (EPS) network.

The core network of the wireless evolution network mainly includes three logics: Mobility Management Entity (MME), Serving Gateway (SGW), and Packet Data Network Gateway (PGW). Functional body.

Since many services of the operator are running in the CS domain of GPRS/UMTS, in order to reuse the existing CS service in the EPS network, 3GPP proposes the CS service back to the traditional network (CS Fallback; CSFB) technology. The user equipment is registered in the EPS network by performing the joint attach to the MSC/VLR of the circuit domain. When the CS service needs to be performed, the user equipment returns to the second generation mobile communication according to the requirements of the EPS network (The 2nd Generation; 2G for short) / The third generation mobile communication (The 3rd Generation; referred to as: 3G) The network completes the CS business. The main feature of CSFB technology is that the MME is connected to the MSC/VLR of the CS domain through the SGs interface.

However, the SGs interface is a new interface. This means that the operator needs to upgrade all MSC/VLRs on the live network when deploying CSFB. Even if the operator does not need CSFB, in order to support CSFB roaming, all MSCs need to be upgraded. VLR, increased operating costs. Summary of the invention

Embodiments of the present invention provide a method for returning a circuit switched domain service to a legacy network and a mobile management network element to reduce the cost of the CSFB solution.

The embodiment of the invention provides a method for returning a circuit switched domain service to a traditional network (CSFB), including: The mobile management network element receives the short message sent by the user equipment;

If the CSFB type of the user equipment is Gs CSFB, the mobility management network element sends a message including the CSFB indication to the evolved base station to trigger the user equipment to return to the legacy network.

The embodiment of the invention further provides a method for returning a circuit switched domain service to a traditional network (CSFB), including:

If the CSFB type of the user equipment is Gs CSFB, the user equipment sends an extended service request message to the mobility management network element, so that the mobility management network element sends a message including the CSFB indication to the evolved base station to trigger the user equipment. Return to the traditional network.

The embodiment of the invention further provides a mobility management network element, including:

a first receiving module, configured to receive a short message sent by the user equipment;

The first processing module is configured to: when the circuit switched domain service of the user equipment returns to the legacy network (CSFB) type is Gs CSFB, send a message including the CSFB indication to the evolved base station, to trigger the user equipment to return to the traditional network.

The embodiment of the invention further provides a user equipment, including:

a second sending module, configured to send an extended service request message to the mobility management network element when the circuit switched domain service of the user equipment returns to the legacy network (CSFB) type is Gs CSFB, so that the mobility management network element sends the The CSFB indicates a message to the evolved base station to trigger the user equipment to return to the legacy network.

After the mobile management network element receives the short message sent by the user equipment, when the CSFB type of the user equipment is Gs CSFB, the mobility management network element sends a message including the CSFB indication to the evolved base station, and triggers the user equipment to return. Traditional network; or, when the CSFB type of the user equipment is Gs CSFB, the user equipment sends an extended service to the mobility management network element. The message is sent to enable the mobility management network element to send a message including the CSFB indication to the evolved base station, and trigger the user equipment to return to the legacy network. The method for returning the circuit switched domain service to the traditional network provided by the embodiment of the present invention does not need to upgrade a large number of MSC/VLR devices in the existing network, thereby reducing the cost of the CSFB solution. DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief description of the drawings used in the embodiments or the prior art description will be briefly described below. Obviously, the drawings in the following description It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any creative work.

1 is a flow chart of an embodiment of a method for returning a circuit switched domain service to a legacy network according to the present invention;

2 is a flow chart of another embodiment of a method for returning a circuit switched domain service to a legacy network according to the present invention;

3 is a flow chart of still another embodiment of a method for returning a circuit switched domain service to a legacy network according to the present invention;

4 is a flow chart of still another embodiment of a method for returning a circuit switched domain service to a legacy network according to the present invention;

5 is a flow chart of an embodiment of an attaching process or a tracking area/location area updating process according to the present invention;

6 is a schematic diagram of an embodiment of using Gs CSFB according to the present invention;

Figure 7 shows the use of only short message service (Short Message Service over SGs) Only; short for: SMS-only) - a schematic diagram of an embodiment;

8 is a schematic structural diagram of an embodiment of a mobility management network element according to the present invention;

9 is a schematic structural diagram of another embodiment of a mobility management network element according to the present invention;

FIG. 10 is a schematic structural diagram of an embodiment of a user equipment according to the present invention. detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is a partial embodiment of the invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without departing from the inventive work are all within the scope of the present invention.

1 is a flow chart of an embodiment of a method for returning a circuit switched domain service to a legacy network according to the present invention. As shown in FIG. 1, the method may include:

Step 101: The mobile management network element receives the short message sent by the user equipment.

Step 102: If the CSFB type of the user equipment is Gs CSFB, the mobility management network element sends a message including the CSFB indication to the evolved base station to trigger the user equipment to return to the traditional network.

The CSFB type (CSFB Type) in this embodiment may include: Gs circuit switched domain service return legacy network (GS CSFB), SGs circuit switched domain service return legacy network (SGs CSFB) or SMS-only. The embodiment of the present invention does not limit the name of the CSFB type.

In this embodiment, the traditional network refers to the Global System for Mobile Communications Enhanced Data Rate for GSM Evolution Radio Access Network (GERAN) or universal shift. The Universal Mobile Telecommunications System Territorial Radio Access Network (UTRAN) can be called 2G/3G, and can also be called GERAN/UTRAN.

In this embodiment, before the Mobile Originating Short Message Service (MO SMS) is performed, the Attach Procedure or the Tracking Area Update Procedure is performed. Abbreviation: Tracking area update process), the mobile management NE can know the CSFB type of the user equipment, such as Gs CSFB or SMS-only. The implementation process is as follows: The mobility management network element may receive an attach request message or a tracking area update request message sent by the user equipment, and the mobility management network element determines the CSFB type of the user equipment according to the attach request message or the tracking area update request message, and the network capability. Or the mobility management network element determines the CSFB type of the user equipment according to the attach request message or the tracking area update request message, the network capability, and the configured CSFB type of the user equipment; and then the mobility management network element completes according to the CSFB type of the user equipment. Update to the location of the mobile switching center/visit location register and complete the location update of the mobile switching center/visit location register in the circuit switched domain; the mobile management network element to the user

The device sends an attach accept message or a tracking area update accept message.

In this embodiment, the configuration CSFB type of the user equipment may be part of the user equipment subscription data, for example: a new cell may be added to the user equipment subscription data: a CSFB type (Subscriber CSFB Type); a mobile management network element The location update request message may be sent to the home location register or the home subscriber server, and then received by the home location register or the location update accept message sent by the home subscriber server, the location update accept message including the user equipment subscription data, and the mobile management network element may be from the user. Know the user in the device subscription data The CSFB type of the device is configured. Alternatively, the mobility management network element can learn the configuration CSFB type of the user equipment according to the information locally configured by the mobility management network element. For example, the mobility management network element locally configures the user equipment belonging to the public land mobile communication network. Configure the CSFB type (Configuration Public Land Mobile-communication Network User CSFB Type).

In this embodiment, the network capability may include the network supporting SMS-only, Gs CSFB or SGs CSFB.

Specifically, the mobility management network element determines, according to the attach request message or the tracking area update request message, the network capability, and the configuration CSFB type of the user equipment, that the CSFB type of the user equipment may be: if the attach request message or the tracking area update request message The device does not carry only the short message service indication, and the network supports Gs CSFB, and the configuration CSFB type of the user equipment is Gs CSFB, then it is determined that the CSFB type of the user equipment is Gs CSFB; or

If the attachment request message or the tracking area update request message is not carried and only the short message service indication is used, and the network supports Gs CSFB, and the configuration CSFB type of the user equipment is SGs CSFB, it is determined that the CSFB type of the user equipment is Gs CSFB.

Specifically, the location update of the mobility management network element to the mobile switching center/visit location register according to the CSFB type of the user equipment may be: if the CSFB type of the user equipment is Gs CSFB, the mobility management network element completes to move through the Gs interface. The location of the switching center/visit location register is updated.

In the above embodiment, after the mobile management network element receives the short message sent by the user equipment, when the CSFB type of the user equipment is Gs CSFB, the mobility management network element sends a message including the CSFB indication to the evolved base station, and the evolved base station triggers the user equipment. Return to the traditional network. This embodiment provides The method of returning the circuit-switched domain service to the traditional network does not require upgrading the operator's large number of existing networks.

MSC/VLR equipment reduces the cost of the CSFB solution.

2 is a flow chart of another embodiment of a method for returning a circuit switched domain service to a legacy network according to the present invention. This embodiment describes the flow of the CSFB by the MME in the embodiment shown in FIG. 1 of the present invention. As shown in FIG. 2, the method may include:

Step 201: If the user equipment (User Equipment; UE) is in an idle state, the UE first triggers a service request procedure, so that the UE enters a connected state (Active Mode or Connected Mode), and then step 202 is performed. If the UE is already in the connected state, step 201 may be skipped and step 202 is directly performed.

Step 202: When the UE is ready to perform the MO SMS service, the short message service (Short Message Service: SMS) message is encapsulated in an Uplink Non-Access Stratum Transport message and sent to the MME.

In this embodiment, after receiving the uplink non-access stratum transmission message, the MME learns the CSFB type of the UE according to the locally stored UE context information. If the CSFB type of the UE is Gs CSFB, the MME needs to migrate the UE to the 2G/3G network to complete the short message service, that is, perform steps 203 to 206. If the CSFB type of the UE is SMS-only, the MME can pass the MME. The SGs interface forwards the short message and performs the short message service (SMS over SGs) standard process through the SGs interface, and details are not described herein.

Step 203: The MME sends an S1 Application Layer Protocol (SI Application Protocol; S1-AP) request message to the eNodeB, where the S1-AP request message includes a C SFB indication.

Step 204: The eNodeB sends an S1-AP response message to the MME.

Step 205, the eNodeB performs a packet switched domain handover (PS Handover; referred to as PS HO), A process such as Network Assisted Cell Change (NACC) or Radio Resource Control Connection Release (RRC Connection Release) is used to migrate the UE to the 2G/3G network.

The execution sequence of the step 204 and the step 205 is not limited in this embodiment, and the step 204 and the step 205 may be performed in parallel or sequentially.

Step 206: After sending a service request to the MSC/VLR to establish a CS connection in the 2G/3G network, the UE sends an uplink short message to the MSC/VLR, and completes the subsequent short message service flow, which is not described here.

A typical process in step 206 is: if no response is received for the uplink short message sent by the UE in the EPS network, the UE initiates a short message retransmission process, thereby ensuring that the UE resends the uplink in the 2G/3G network. Short message, complete the short message business process.

The circuit switching domain service provided by the foregoing embodiment returns the traditional network, and does not need to upgrade a large number of existing MSC/VLR devices of the operator, thereby reducing the cost of the CSFB solution; and solving the problem of CSFB roaming, and accelerating the matureness of the voice solution. And network deployment of LTE.

3 is a flow chart of still another embodiment of a method for returning a circuit switched domain service to a legacy network according to the present invention. As shown in FIG. 3, the method may include:

Step 301: If the CSFB type of the user equipment is Gs CSFB, the user equipment sends an extended service request message to the mobility management network element.

Step 302: The mobility management network element sends a message including the CSFB indication to the evolved base station, and triggers the user equipment to return to the legacy network.

The CSFB type in this embodiment may include: Gs CSFB, SGs CSFB or SMS-only. The embodiment of the present invention does not limit the name of the CSFB type. In this embodiment, the traditional network refers to GERAN or UTRAN, which may be called 2G/3G, and may also be called GERAN/UTRAN.

In this embodiment, before the MO SMS or the user originating voice service (Mobile Calling Call; MO Call), the user equipment can know the CSFB type of the user equipment, such as Gs CSFB, through the attach process or the tracking area update process. Or SMS-only. The implementation process is as follows: The mobility management network element may receive an attach request message or a tracking area update request message sent by the user equipment, and then, the mobility management network element determines the user equipment according to the attach request message or the tracking area update request message, and the network capability. Or the CSFB type; or, the mobility management network element determines the CSFB type of the user equipment according to the attach request message or the tracking area update request message, the network capability, and the configured CSFB type of the user equipment; and then the mobility management network element is configured according to the user equipment The CSFB type completes the location update to the mobile switching center/visit location register and completes the location update of the mobile switching center/visit location register in the circuit switched domain; then the mobility management network element can send an attach accept message or a tracking area update accept to the user equipment The message, the Attach Accept message or the Tracking Area Update Accept message contains the CSFB type of the user equipment.

In this embodiment, the configuration CSFB type of the user equipment may be part of the user equipment subscription data, for example: a new cell may be added to the user equipment subscription data: a CSFB type (Subscriber CSFB Type); a mobile management network element The location update request message may be sent to the home location register or the home subscriber server, and then received by the home location register or the location update accept message sent by the home subscriber server, the location update accept message including the user equipment subscription data, and the mobile management network element may be from the user. The configuration CSFB type of the user equipment is obtained in the device subscription data; or, the mobility management network element may be based on the mobility management network element The configuration information is used to learn the configuration CSFB type of the user equipment. For example, the mobility management network element locally configures the Configuration Public Land Mobile-Communication Network User CSFB Type.

In the above embodiment, when the CSFB type of the user equipment is Gs CSFB, the user equipment sends an extended service request message to the mobility management network element, so that the mobility management network element sends a message including the CSFB indication to the evolved base station, and triggers the user equipment to return. Traditional network. The circuit switching domain service provided in this embodiment returns a traditional network, and does not need to upgrade a large number of operators' existing networks. MSC/VLR equipment reduces the cost of the CSFB solution.

4 is a flow chart of still another embodiment of a method for returning a circuit switched domain service to a legacy network according to the present invention. This embodiment describes a flow of CSFB performed by the MME in the embodiment shown in FIG. 3 of the present invention. As shown in FIG. 4, the method may include:

Step 401: The UE sends an extended service request message to the MME, where the extended service request message includes a CSFB indication.

When the UE needs to perform the MO SMS service, if the CSFB type of the UE is Gs CSFB, the UE sends an extended service request message including the CSFB indication to the MME, and then performs steps 402 to 405, where the UE learns the CSFB type. See step 505 in the following embodiment for details. If the CSFB type of the UE is SMS-only, the UE may initiate a service request procedure or the UE may directly encapsulate the SMS message to the uplink non-access stratum transmission message and send the message to the MME, so that the MME can forward the uplink short message through the SGs interface. The SMS over SGs standard process is implemented and will not be described here.

Step 402: The MME sends an S1-AP request message to the evolved Node B (evolved NodeB; eNodeB for short), where the S1-AP request message includes a CSFB indication.

Step 403: The eNodeB sends an S1-AP response message to the MME.

Step 404: The eNodeB performs a process such as PS HO, NACC, or RRC connection release to migrate the UE to the 2G/3G network.

The execution sequence of step 403 and step 404 is not limited in this embodiment, and step 403 and step 404 may be performed in parallel or sequentially.

Step 405: After sending a service request to the MSC/VLR to establish a CS connection in the 2G/3G network, the UE sends an uplink short message to the MSC/VLR, and completes a subsequent short message service process. I will not repeat them here.

Before performing the MO SMS procedure of the embodiment shown in FIG. 2 or FIG. 4, the MME can learn the CSFB type of the UE through the attach procedure or the tracking area/location area update procedure. The attachment process or tracking area/location area update process is described below in conjunction with Figure 5.

FIG. 5 is a flowchart of an embodiment of an attaching process or a tracking area/location area updating process according to the present invention. As shown in FIG. 5, the attaching process or the tracking area/location area updating process may include:

Step 501: The UE sends an attach request (Attach Request) message to the MME, indicating that the attach procedure is a combined EPS/International Mobile Subscriber Identity attach (abbreviation: combined EPS/IMSI attach) process; or, the UE sends a tracking area update request. (Tracking Area Update Request; TAU Request) message to the MME, indicating that the tracking area/location area update process is a combined tracking area/Location Area Update Request process or a joint tracking area/location Zone update and IMSI attach request flow.

Step 502a: The MME sends a Location Update Request message to the Home Location Register (HLR)/Home Subscriber Server (hereinafter referred to as HSS).

Step 502b: The HLR/HSS sends a Location Update Accept message to the MME, where the location update accept message includes the subscription data of the UE. In this embodiment, the subscription data of the UE may include a configured CSFB type of the UE. The configured CSFB type of the UE may refer to a type of CSFB that the UE allows or recommends in a certain carrier network, for example: Gs CSFB; or the configured CSFB type of the UE may refer to the UE being allowed in the roaming carrier network or The recommended CSFB type, for example: Gs CSFB; or, the configured CSFB type of the UE may refer to the CSFB type that the UE allows or recommends in all the carrier networks, for example: Gs CSFB;

In this embodiment, the specific configuration of the CSFB type of the UE may include: (1) a yes or no form: for example, whether the UE is allowed to use the Gs CSFB in the roaming network or the local network; or

(2) The form of enumeration: For example, the CSFB types supported by the UE include: Gs CSFB.

In this embodiment, when performing the contract processing, the HLR/HSS may sign different CSFB types for the UE for different networks, for example: belonging to the Public Land Mobile-Communication Network-A (referred to as: In the subscription data of the UE of the PLMN-A), the configuration CSFB type of the UE indicates that the UE is recommended to use the Gs CSFB when roaming to the Public Land Mobile-Communication Network-B (abbreviation: PLMN-B) , indicating that the UE recommends using SGs CSFB when using PLMN-A

The foregoing is only a few examples of the specific configuration of the CSFB type of the UE. The specific configuration of the CSFB type is not limited in the embodiment of the present invention.

In this embodiment, the manner of configuring the CSFB type of the UE is not limited to the subscription data stored in the UE, and is obtained from the HLR/HSS in step 502b. The MME may also learn the configuration CSFB type of the UE according to the local configuration information of the MME. Specifically, the MME may be pre-configured based on a public land mobile communication network (Public Land Mobile-communication) Network; abbreviated as: PLMN) granular CSFB type, for example: All non-local UEs (ie, other PLMN subscription UEs) can be configured to use Gs CSFB; or, the MME can configure different PLMN UEs to use different CSFB types, for example: The CSFB type in the MME of the PLMN-A may be configured to indicate that the UE accessing the PLMN-B uses the SMS over SGs service, and the UE accessing the PLMN-A or the PLMN-C uses the Gs CSFB. The foregoing is only a few examples of the MME configuring the CSFB type of the UE according to the local configuration information of the MME, which is not limited by the embodiment of the present invention. Any MME learns the configuration of the CSFB type of the UE according to the local configuration information of the MME. All should fall within the scope of protection of the embodiments of the present invention.

Step 503: The MME determines, according to the attach request message or the tracking area update request message, the network capability, the CSFB type of the user equipment, or the MME, according to the attach request or the tracking area update request message, the network capability, and the configuration CSFB of the UE. The type determines the CSFB type of the UE.

Specifically, the following situations are included:

In an implementation manner of this embodiment, if the network supports the Gs CSFB and/or the SMS-only: if the attach request message or the tracking area update request message does not carry the SMS-only indication (the MME does not obtain the configuration of the UE at this time) CSFB type), the MME determines that the CSFB type of the UE is Gs CSFB; or

If the SMS-only indication is not carried in the attach request message or the tracking area update request message, and the configured CSFB type of the UE is Gs CSFB, the MME determines that the CSFB type of the UE is Gs CSFB; or

If the SMS-only indication is not carried in the attach request message or the tracking area update request message, and the configured CSFB type of the UE is SGs CSFB, the MME determines the CSFB type of the UE. For Gs CSFB or SMS-only; or,

If the SMS-only indication is not carried in the attach request message or the tracking area update request message, and the configured CSFB type of the UE is SMS-only, the MME determines that the CSFB type of the UE is SMS-only; or

If the attach request message or the tracking area update request message carries an SMS-only indication (in which case the MME does not acquire the configured CSFB type of the UE), the MME determines that the CSFB type of the UE is SMS-only; or

If the attach request message or the tracking area update request message carries an SMS-only indication, and the configured CSFB type of the UE is Gs CSFB, SGs CSFB or SMS-only, the MME determines that the CSFB type of the UE is SMS-only.

In another implementation manner of this embodiment, if the current network supports SGs CSFB and/or SMS-only, where SGs CSFB refers to voice services through SGs CSFB to 2G/3G and directly on the EPS network through the SGs interface. Short message service (CSFB and SMS over SGs or SGs CSFB and SMS over SGs):

If the SMS-only indication is not carried in the attach request message or the tracking area update request message, and the configured CSFB type of the UE is Gs CSFB, the MME determines that the CSFB type of the UE is SGs CSFB; or

If the attach request message or the tracking area update request message carries an SMS-only indication, and the configured CSFB type of the UE is Gs CSFB, the MME determines that the CSFB type of the UE is SMS-only.

The foregoing is only a few examples of the MME determining the type of the CSFB of the UE. The embodiment of the present invention is not limited thereto. Any MME according to the attach request message or the tracking area update request message And the network capability determines the CSFB type of the UE; or the manner in which the MME determines the CSFB type of the UE according to the attach request message or the tracking area update request message, the network capability, and the configuration CSFB type of the UE should fall into the embodiment of the present invention. The scope of protection.

Step 504, the MME completes the location update to the MSC/VLR, and the MSC/VLR completes the location update in the circuit switched domain.

Specifically, (1) when the MME determines that the CSFB type of the UE is SGs CSFB, the MME can complete the location update to the MSC/VLR through the SGs interface, and then the MSC/VLR completes the location update in the CS domain, and the UE can Perform SMS service in the LTE network, and perform CS call service on the CSFB to the 2G/3G network; or

(2) When the MME determines that the CSFB type of the UE is SMS-only, the MME can complete the location update to the MSC/VLR through the SGs interface, and then the MSC/VLR completes the location update in the CS domain, and the UE can only be in the LTE. Perform SMS business in the network; or,

(3) When the MME determines that the CSFB type of the UE is Gs CSFB, the MME can complete the location update to the MSC/VLR through the Gs interface, and then the MSC/VLR completes the location update in the CS domain. At this time, the SMS service needs and CS. The call is returned to the 2G/3G network.

Step 505: The MME returns an attach accept message or a tracking area update accept message to the UE. The specific implementation is as follows:

(1) When the MME determines that the CSFB type of the UE is the SGs CSFB, the MME sends a standard CSFB attach accept message or a tracking area update accept message to the UE; or

(2) When the MME determines that the CSFB type of the UE is the SMS over SGs service or the SMS-only, the MME carries an SMS-only indication in the attach accept message or the tracking area update accept message; or (3) When the MME determines that the CSFB type of the UE is Gs CSFB, corresponding to the description of the embodiment shown in FIG. 1 of the present invention, the UI may send a standard CSFB attach accept message or a tracking area update accept message to the UE, that is, send The Gs CSFB indication is not included in the Attach Accept message or the Tracking Area Update Accept message; or, corresponding to the description of the embodiment shown in FIG. 3 of the present invention, the MME may carry the Gs CSFB indication in the Attach Accept message or the Tracking Area Update Accept message. In order to inform the UE that the current network provides the Gs CSFB for the UE; the specific implementation of the Gs CSFB indication may be an extended attach accept message or a tracking area update accept message, and an additional Gs CSFB is added in the attach accept message or the tracking area update accept message. Indicates, or extends the enumeration value of the Additional update result information element of the Attach Accept message or the Tracking Area Update Accept message so that the added enumeration value is a Gs CSFB indication. The above is only two examples of specific implementations of the Gs CSFB indication. The specific implementation manner of the Gs CSFB indication is not limited in the embodiment of the present invention.

The method provided by the embodiment shown in FIG. 1 to FIG. 5 can be applied to the architecture shown in FIG. 6. FIG. 6 is a schematic diagram of an embodiment of using Gs CSFB according to the present invention. In FIG. 6, the MME passes the traditional Gs interface. Connect to the MSC/VLR to provide Gs CSFB for the UE. In the architecture shown in FIG. 6, the UE performs the joint attach procedure of the embodiment shown in FIG. 5 of the present invention, completes the location update to the MSC/VLR through the Gs interface, and subsequently performs the standard SGs CSFB process to complete the service processing of the CS domain. Since Gs CSFB cannot support the delivery of short messages in the EPS network, the UE needs to return to the 2G/3G network before performing the short message service.

In the embodiment of the present invention, for a UE that only needs the SMS service, the operator can still provide an SMS over SGs service by supporting the SGs interface and connecting to an MSC/VLR through the SGs interface, as shown in FIG. 7, FIG. 7 is The present invention uses SMS-only - an illustration of an embodiment Figure; At this point, because there is no need to upgrade all MSC/VLRs in the whole network, it can effectively reduce operating costs. In this embodiment of the present invention, a UE can only select an SGs interface or a Gs interface to register with a corresponding MSC/VLR.

A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The foregoing steps include the steps of the foregoing method embodiments; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

FIG. 8 is a schematic structural diagram of an embodiment of a mobility management network element according to the present invention. The mobility management network element in this embodiment may implement the process of the embodiment shown in FIG. 1 of the present invention. As shown in FIG. 8, the mobility management network element may be The method includes: a first receiving module 81 and a first processing module 82.

The first receiving module 81 is configured to receive a short message sent by the user equipment, where the first processing module 82 is configured to: when the CSFB type of the user equipment is Gs CSFB, send a message including the CSFB indication to the evolved base station, to trigger The user device returns to the traditional network.

In the above embodiment, after receiving the short message sent by the user equipment, when the CSFB type of the user equipment is Gs CSFB, the first processing module 82 sends a message including the CSFB indication to the evolved base station, triggering the user. The device returns to the traditional network. When the mobile management network element returns to the traditional network processing in the circuit switching domain service, it does not need to upgrade a large number of existing MSC/VLR devices of the operator, thereby reducing the cost of the CSFB solution.

FIG. 9 is a schematic structural diagram of another embodiment of a mobility management network element according to the present invention. The difference is that the mobility management network element shown in FIG. 9 may further include: A determination module 83 and a first transmission module 84. The first receiving module 81 is further configured to receive an attach request message or a tracking area update request message sent by the user equipment.

a first determining module 83, configured to determine a CSFB type of the user equipment;

The first sending module 84 is configured to send an attach accept message or a tracking area update accept message to the user equipment.

In an implementation manner of this embodiment, the first determining module 83 may include: a first type determining submodule 831. In another implementation manner of this embodiment, the first determining module 83 may include: Module 832 and second type determination sub-module 833.

The first type determining submodule 831 is configured to determine a CSFB type of the user equipment according to the attach request message or the tracking area update request message, and the network capability;

The type obtaining sub-module 832 is configured to learn the configuration CSFB type of the user equipment, and the second type determining sub-module 833 is configured to: according to the attach request message or the tracking area update request message, the network capability, and the user equipment learned by the type obtaining sub-module 832 The configuration CSFB type determines the CSFB type of the user device.

Specifically, the second type determining submodule 833 may not carry the short message service indication in the attach request message or the tracking area update request message, and the network supports Gs CSFB, and the configuration CSFB type of the user equipment is Gs CSFB, The CSFB type of the user equipment is Gs CSFB; or,

The second type determining sub-module 833 may not carry the short message service indication in the attach request message or the tracking area update request message, and the network supports Gs CSFB, and the user equipment determines that the CSFB type is SGs CSFB. The CSFB type is Gs CSFB.

The foregoing mobility management network element does not need to perform the circuit switching domain service back to the traditional network processing. To upgrade the operator's large number of existing MSC/VLR devices, the cost of the CSFB solution is reduced; and the CSFB roaming problem is solved, and the mature voice solution and LTE network deployment are accelerated.

FIG. 10 is a schematic structural diagram of an embodiment of a user equipment according to the present invention. The user equipment in this embodiment may implement the process of the embodiment shown in FIG. 3 of the present invention. As shown in FIG. 10, the user equipment may include: a second sending module. 1001. When the CSFB type of the user equipment is Gs CSFB, send an extended service request message to the mobility management network element, so that the mobility management network element sends a message including the CSFB indication to the evolved base station, to trigger the user equipment to return. Traditional network.

Further, the user equipment may further include: a second receiving module 1002;

The second sending module 1001 is further configured to send an attach request message or a tracking area update request message to the mobility management network element.

The second receiving module 1002 is configured to receive an attach accept message or a tracking area update accept message sent by the mobility management network element, where the attach accept message or the tracking area update accept message includes a CSFB type of the user equipment.

In the above embodiment, when the CSFB type of the user equipment is Gs CSFB, the second sending module 1001 sends an extended service request message to the mobility management network element, so that the mobility management network element sends a message including the CSFB indication to the evolved base station, and triggers The user device returns to the traditional network. When the user equipment returns to the traditional network processing in the circuit switched domain service, the operator does not need to upgrade a large number of existing MSC/VLR devices of the operator, thereby reducing the cost of the CSFB solution.

A person skilled in the art can understand that the drawings are only a schematic diagram of a preferred embodiment, and the modules or processes in the drawings are not necessarily required to implement the invention.

A person skilled in the art may understand that the modules in the apparatus in the embodiment may be distributed in the apparatus of the embodiment according to the description of the embodiment, or may be changed according to the implementation. In one or more devices of the example. The modules of the above embodiments may be combined into one module, or may be further split into multiple sub-modules.

It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that: The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced. The modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

Rights request

A method for returning a circuit switched domain service to a legacy network (CSFB), the method comprising:

The mobile management network element receives the short message sent by the user equipment;

The method according to claim 1, wherein before the mobile management network element receives the short message sent by the user equipment, the method further includes:

Receiving, by the mobility management network element, an attach request message or a tracking area update request message sent by the user equipment;

Determining, by the mobility management network element, a CSFB type of the user equipment;

The mobility management network element sends an attach accept message or a tracking area update accept message to the user equipment.

The method according to claim 2, wherein the mobility management network element determines that the CSFB type of the user equipment comprises:

Determining, by the mobility management network element, the CSFB type of the user equipment according to the attach request message or the tracking area update request message, and network capability; or

The mobile management network element learns the configuration CSFB type of the user equipment, and determines the CSFB of the user equipment according to the attach request message or the tracking area update request message, the network capability, and the configuration CSFB type of the user equipment. Types of.

4. The method according to claim 3, wherein the mobility management network element is obtained Knowing the configuration CSFB types of the user equipment include:

The mobility management network element sends a location update request message to the home location register or the home subscriber server, and receives the home location register or a location update accept message sent by the home subscriber server, where the location update accept message includes the user The configuration of the device is of the CSFB type; or,

The mobility management network element learns the configuration CSFB type of the user equipment according to the information locally configured by the mobility management network element.

The method according to claim 3 or 4, wherein the determining the user according to the attach request message or the tracking area update request message, network capability, and configuration CSFB type of the user equipment The CSFB types of the device include:

Determining the user equipment if the connection request message or the tracking area update request message does not carry only the short message service indication, and the network supports Gs CSFB, and the configuration CSFB type of the user equipment is Gs CSFB The CSFB type is Gs CSFB; or,

If the attach request message or the tracking area update request message does not carry only the short message service indication, and the network supports Gs CSFB, and the configuration CSFB type of the user equipment is SGs CSFB, determining the user equipment The CSFB type is Gs CSFB.

The method according to claim 5, wherein after the mobility management network element determines the CSFB type of the user equipment, the method further includes:

The mobility management network element completes the location update to the mobile switching center/visit location register according to the CSFB type of the user equipment.

7. The method according to claim 6, wherein the mobility management network element completes the bit to the mobile switching center/visit location register according to the CSFB type of the user equipment. Updates include:

If the CSFB type of the user equipment is Gs CSFB, the mobility management network element completes the location update to the mobile switching center/visit location register through the Gs interface.

8. A method for returning a legacy network (CSFB) to a circuit switched domain service, the method comprising:

The method according to claim 8, wherein before the user equipment sends the extended service request message to the mobility management network element, the method further includes:

The user equipment sends an attach request message or a tracking area update request message to the mobility management network element;

The user equipment receives an attach accept message or a tracking area update accept message sent by the mobility management network element, and the attach accept message or the tracking area update accept message includes a CSFB type of the user equipment.

The method according to claim 9, wherein the attach accept message or the tracking area update accept message includes the CSFB type of the user equipment, including:

The attach accept message or the tracking area update accept message carries a Gs CSFB indication.

The method according to claim 9, wherein before the user equipment receives the attach accept message or the tracking area update accept message, the method further includes:

Determining, by the mobility management network element, a CSFB type of the user equipment according to the attach request message or the tracking area update request message, and a network capability; or The mobile management network element learns the configuration CSFB type of the user equipment, and determines the CSFB of the user equipment according to the attach request message or the tracking area update request message, the network capability, and the configuration CSFB type of the user equipment. Types of.

The method according to claim 11, wherein the mobility management network element learns that the configuration of the user equipment is a CSFB type, including:

The method according to claim 11 or 12, wherein the determining the user according to the attach request message or the tracking area update request message, network capability, and configuration CSFB type of the user equipment The CSFB types of the device include:

Determining CSFB of the user equipment if the attach request message or the tracking area update request message does not carry only the short message service indication, and the network supports Gs CSFB, and the configuration CSFB type of the user equipment is SGs CSFB The type is Gs CSFB.

14. A mobility management network element, comprising:

a first receiving module, configured to receive a short message sent by the user equipment; a first processing module, configured to: when the circuit switched domain service of the user equipment returns to a traditional network

When the type (CSFB) is Gs CSFB, a message containing the CSFB indication is sent to the evolved base station to trigger the user equipment to return to the legacy network.

The mobile management network element according to claim 14, further comprising: a first determining module and a first sending module;

The first receiving module is further configured to receive an attach request message or a tracking area update request message sent by the user equipment;

The first determining module is configured to determine a CSFB type of the user equipment;

The first sending module is configured to send an attach accept message or a tracking area update accept message to the user equipment.

The mobile management network element according to claim 15, wherein the first determining module comprises:

a first type determining submodule, configured to determine, according to the attach request message or the tracking area update request message, a network capability, a CSFB type of the user equipment; or

The first determining module includes:

a type obtaining submodule, configured to learn a configuration CSFB type of the user equipment, and a second type determining submodule, configured to update a request message according to the attach request message or the tracking area, network capability, and the type acquiring sub Module configuration of the user device

The CSFB type determines the CSFB type of the user equipment.

17. The mobility management network element of claim 16 wherein:

The second type determining submodule is specifically configured to not use only the short message service indication in the attach request message or the tracking area update request message, and the network supports Gs CSFB, And when the configuration CSFB type of the user equipment is Gs CSFB, determining that the CSFB type of the user equipment is Gs CSFB; or

The second type determining submodule is specifically configured to not use only the short message service indication in the attach request message or the tracking area update request message, and the network supports Gs CSFB, and the configuration CSFB type of the user equipment When the SGs CSFB, it is determined that the CSFB type of the user equipment is Gs CSFB.

18. A user equipment, comprising:

The user equipment according to claim 18, further comprising: a second receiving module;

The second sending module is further configured to send an attach request message or a tracking area update request message to the mobility management network element;

The second receiving module is configured to receive an attach accept message or a tracking area update accept message sent by the mobility management network element, where the attach accept message or the tracking area update accept message includes a CSFB type of the user equipment.