WO2014180405A1

WO2014180405A1 - Paging method and mobile switching center

Info

Publication number: WO2014180405A1
Application number: PCT/CN2014/078659
Authority: WO
Inventors: 刘竞翔; 凌军; 曹小飞
Original assignee: 中兴通讯股份有限公司
Priority date: 2013-09-12
Filing date: 2014-05-28
Publication date: 2014-11-13
Also published as: CN104469943A

Abstract

A paging method and a mobile switching center, the method comprising: after receiving a called service request, an SC or a VLR paging a terminal in a circuit-switched domain network; determining, during the paging process, whether the terminal has transferred to a system architecture evolution (SAE) network; if so, then an MSC or VLR paging the terminal by means of an SGs interface. The embodiments of the present invention allow an MSC/VLR to add an SGs interface during a circuit domain paging process, thus solving the problem of paging failure caused by a UE roaming among different networks, and increasing the success rate of a UE in a circuit-switched domain and SAE hybrid network.

Description

Paging method and mobile switching center

Technical field

The present invention relates to the field of paging technologies, and in particular, to a paging method and a mobile switching center. Background technique

The System Architecture Evolution (SAE) network is a new generation of wireless network technology developed by the 3GPP (3GPP, 3rd Generation Partnership Project) to replace traditional circuit domain switching networks, including Long Term Evolution (LTE). And the evolution of the packet core network (EPC, Evolved Packet Core), its architecture is shown in Figure 1, the function of each network element is as follows.

User Equipment (UE), which has access to the Global Mobile Telecommunication System Radio Access Network/GSM EDGE Radio Access Network (UTRAN/GERAN, GPRS (General Packet Radio Service) Wireless packet service) Wireless network, UTRAN stands for 3G, GERAN stands for 2G) and LTE two wireless networks. Due to capacity limitations and energy saving requirements, UEs can only reside in one wireless system (called Single Radio) at the same time. For example, when the UE resides in LTE, it cannot receive the PDCCH from UTRAN/GERAN. Call the message.

An evolved NodeB (eNodeB) can provide a ratio on an air interface.

UTRAN has higher uplink and downlink rates, lower transmission delays and more reliable wireless transmission. The eNodeB provides radio resources for the access of the terminal, and establishes an S1 control plane link with the core network MME.

Mobility Management Entity (MME) is a control plane entity that temporarily stores user data. It is responsible for managing and storing UE context (eg, UE/user ID, mobility management status, user security parameters, etc.). The user is assigned a temporary identifier (GUTI), and the MME is responsible for authenticating the user when the user accesses the LTE. The SAE Gateway (System Architecture Evolution GW, SAE GW for short) is a user plane entity responsible for user plane data routing processing. The SAE GW is generally divided into a Serving GW and a Packet Data Network Gateway (PDN GW). The Serving GW is responsible for the mobility anchor between LTE and UMTS. The idle data triggers the MME and SGSN paging in the idle state. PDN GW It is responsible for the gateway function of the UE to access the PDN (Packet Data Network), and assigns the user IP (Internet Protocol) address to the user. The PDN GW and the Serving GW may be combined in one physical entity.

The Home Subscriber Server (HSS) is used to save the user's subscription data and record the user's name (ΜΜΕ ΝΑΜΕ).

Figure 1 also shows the architecture of a traditional circuit domain switching network. The core network element has a Mobile Switching Center (MSC) and a Visitor Location Register (VLR). The MSC and the VLR are physically combined.

The 3G radio access controller (Radio Network Controller, RNC for short) or the base station controller (BSC) is responsible for controlling and managing the user's wireless activities.

The traditional circuit domain switching network uses the Home Location Register (HLR) to store the subscriber's subscription information and the address of the VLR. In the called call, the HLR can obtain the Mobile Subscriber Roaming Number (MSRN) from the VLR. In Figure 1, the HLR and HSS are served by one physical network element.

The Gateway Mobile Switching Center (GMSC) is used to route calls to the MSC where the user is located. When there is a call to the mobile subscriber, the GMSC obtains the subscriber's MSRN through the HLR and then routes the call according to the MSRN.

Between the MME network element of the SAE and the VLR of the traditional circuit domain switching network, the SGs interface is the interface between the MME and the MSC. The SAE network replaces the traditional circuit domain switching network is a long-term trend. In this process, since the traditional circuit domain switching network has better wireless coverage and stable service, it is an effective supplement to the SAE network. When SAE is unable to provide satisfactory traditional voice services, it can instead provide services by traditional circuit domain switching networks. This mechanism of fallback to the traditional circuit domain switching network is called Circuit Switch Fallback (CSFB), which can be dropped back to the traditional circuit domain switching network for service. It is a Dual Mode Single Radio UE. The CSFB technology establishes an SGs interface between the MME of the SAE and the VLR of the traditional circuit domain switching network. Through the interface, the MME can enable the UE roaming under the LTE to trigger the location update process of the traditional circuit domain switching network, so that the UE registers in the traditional circuit domain switching network while the SAE is active. The process includes the following steps:

Step 201: The UE in the LTE is powered on or changes the Tracking Area (TA), initiates the ATTACH or Tracking Area Update (TAU) operation.

Step 202: The MME receives the foregoing message, and performs registration in the SAE to the HSS.

Step 203: After the registration is successful, the MME derives a Location Area Identity (LAI) of the UE in the traditional circuit domain switching network by using the tracking area where the UE is located, and locates the corresponding VLR. Through the SGs interface, the MME sends a location update request to the VLR.

Step 204: If the VLR has no user data, or the VLR considers that the user data is unreliable, the VLR sends a location update request to the HLR.

Step 205: The HLR will send an ISD (insert user data request) to the VLR, and the VLR records the user subscription data and returns a response.

Step 206: The HLR returns a success response of the location update, and records the number of the VLR where the user is located. Step 207: The VLR returns a location update complete message to the MME, and modifies the status of the SGs interface to be activated.

After the user registers with the HLR, the SGs interface status of the user is marked as active on the MSC/VLR, so that when the called service is received, the MSC/VLR determines the status and pages the user through the SGs interface. The process is shown in Figure 3, and the corresponding steps include:

Step 301: After receiving the Initial Address Message (IMM) of the external network, the GMSC finds the called HLR according to the called user's telephone number (ie, the MSISDN number), and sends the routing information to the HLR (Send Routing Information, SRI) request, with the user's MSISDN number.

Step 302: The HLR finds the MSC/VLR number registered by the user according to the MSISDN number, and sends a request for providing a Roaming Number (PRN) to the MSC/VLR. At this time, the MSC/VLR is the MSC/VLR that the UE registers from the LTE/EPC. The MSC/VLR allocates the temporary subscriber identity MSRN and returns it to the HLR. The MSRN uniquely identifies the MSC/VLR and the called party

UE.

Step 303: The HLR returns an SRI Response (SRI Response) message to the GMSC, with the MSRN. Step 304: The GMSC routes the call to the MSC/VLR according to the MSRN.

Step 305: The MSC/VLR checks that the status of the SGs interface of the user is activated, and initiates a circuit domain (CS) paging process from the SGs to the MME, and the MME then initiates a CS paging process within the LTE, and returns a service request to the MSC/VLR.

Step 306: The UE falls back to the circuit domain, and initiates a paging response from the traditional circuit domain switching network. Step 307: If necessary, the MSC/VLR performs an access operation.

Step 308: The MSC/VLR sends a call setup request Setup to the UE.

Step 309: The MSC/VLR, the UE completes the remaining called establishment process.

In the above process, the user who has completed the registration of the SGs is paged through the SGs interface to accept the called service. However, there is a scenario in which the user roams to the LTE network during the paging process, causing the MSC/VLR to fail to initiate paging correctly, and the user therefore misses the called service. The scenario includes the following steps:

Step 401: The user initially resides in the circuit domain switching network, so the SGs interface status of the user is idle.

Step 402: The user receives an incoming call request, because the SGs interface status of the user is idle, so the MSC/VLR initiates paging to the user in the circuit domain;

Step 403: The user roams before receiving the paging request, becomes accessing from the LTE network, and initiates tracking area update.

Step 404: The user cannot receive the paging request because the access network is changed, and the paging initiated by the MSC/VLR times out, and the call is released. Summary of the invention

The technical problem to be solved by the embodiments of the present invention is to provide a paging method and a mobile switching center. To solve the problem of paging failure caused by UE roaming between different networks.

In order to solve the above technical problems, the following technical solutions are used:

The embodiment of the invention provides a paging method, including:

After receiving the called service request, the mobile switching center MSC or the visited location register VLR initiates paging of the terminal in the circuit domain switching network;

In the paging process, it is determined whether the terminal has been transferred to the system architecture evolution network, and if so, the MSC or the VLR performs the terminal on the interface through the interface SGs interface between the mobility management entity MME and the mobile switching center MSC. Paging.

Optionally, the above method has the following features:

The step of determining whether the terminal has been transferred to the system architecture evolution network includes:

Upon receiving the location update request message of the SGs interface, the MSC or the VLR determines that the terminal has transferred to the system architecture evolution network.

Optionally, the foregoing method further has the following features: The system architecture evolution network includes: a long-term evolution or an evolved packet core network.

The embodiment of the present invention further provides a mobile switching center, including: a first paging module, a determining module, and a second paging module, where

The first paging module is configured to: after receiving the called service request, initiate paging to the terminal in the circuit domain switching network;

The determining module is configured to: determine, during the paging process, whether the terminal has been transferred to the system architecture evolution network, and if yes, notify the second paging module;

The second paging module is configured to: after receiving the notification of the determining module, the terminal is called by the interface SGs interface between the mobility management entity MME and the mobile switching center MSC.

Optionally, the mobile switching center has the following features:

The determining module is configured to determine whether the terminal has been transferred to the system framework evolution network by: if the location update request message of the SGs interface is received, determining that the terminal has transferred to the system architecture evolution network. Optionally, the mobile switching center has the following features:

The system architecture evolution network includes: a long term evolution or evolved packet core network.

In summary, the embodiment of the present invention provides a paging method and a mobile switching center, which are allowed.

During the circuit domain paging process, the MSC/VLR increases the paging of the SGs interface, thereby solving the paging failure problem caused by the UE roaming between different networks, and increasing the called number of the UE in the circuit domain switching network and the SAE network hybrid network. Business success rate. BRIEF abstract

1 is a structural diagram of a SAE and a conventional circuit domain switching network in the related art;

2 is a flowchart of a traditional circuit domain switching network registration performed by a user in LTE in the related art; FIG. 3 is a flowchart of a LTE user falling back to a traditional circuit domain switching network and receiving a traditional circuit domain switching network incoming call in the related art;

4 is a flowchart of a related art in which a UE roams to an LTE network during paging, thereby causing paging failure;

FIG. 5 is a flowchart of a paging method according to an embodiment of the present invention; FIG.

6 is a flowchart of a paging method of an application example of the present invention;

FIG. 7 is a schematic diagram of an MSC according to an embodiment of the present invention.

Preferred embodiment of the invention

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, in the case of no conflict, the features in the embodiments and the embodiments in the present application may be arbitrarily combined with each other.

FIG. 5 is a flowchart of a paging method according to an embodiment of the present invention. As shown in FIG. 5, the method in this embodiment includes:

511. After receiving the called service request, the mobile switching center MSC or the visited location register VLR initiates paging to the terminal in the circuit domain switching network;

512. In the paging process, determine whether the terminal has been transferred to the SAE network. If yes, the MSC or the VLR pages the terminal through the SGs interface. In this way, the method in this embodiment allows the MSC/VLR to increase the paging of the SGs interface during the paging process of the circuit domain, thereby solving the paging failure problem caused by the UE roaming between different networks, and increasing the circuit domain switching network and the SAE network. The called service success rate of the UE in the hybrid network.

Fig. 6 is a flow chart showing a paging method of an application example of the present invention. In this example, during the paging process of the MSC/VLR, the UE initiates a tracking area update, and the MSC/VLR pages through the SGs interface to access the user. Proceed as follows:

Step 501: After receiving the Initial Address Message (IMM) of the external network, the GMSC finds the called HLR according to the called user's telephone number (ie, MSISDN), and sends the routing information to the HLR (Send Routing Information, SRI). The request, with the user's MSISDN number.

Step 502: The HLR finds the MSC/VLR number registered by the user according to the MSISDN number, and sends a Provide Roaming Number (PRN) request to the MSC/VLR, and the MSC/VLR returns the roaming number to the HLR.

Step 503: The HLR returns the obtained roaming number to the GMSC in an SRI Response message.

Step 504: The GMSC routes the call to the MSC/VLR according to the MSRN.

Step 505: Because the user currently camps on the circuit domain, the SGs interface status of the user is idle, and the MSC/VLR pages the user in the circuit domain, and sends a paging message to the BSC or the RNC.

Step 506: At the same time, the UE roams to the LTE network, and initiates tracking area update under the LTE network. Step 507: The MME receives the tracking area update, and sends an SGs interface location update request message to the MSC/VLR.

Step 508: The MSC/VLR processes the SGs interface location update request message, and returns an SGs interface location update accept message.

Step 509: The MSC/VLR determines that the user has transferred to the LTE network, initiates the SGs interface to find the MME, and waits for the UE to fall back to the circuit domain switching network.

Step 510: The UE rolls back to the circuit domain switching network, and initiates a paging response from the circuit domain switching network. Step 511: If necessary, the MSC/VLR performs an access operation.

Step 512: The MSC/VLR sends a call setup request (Setup) to the UE.

Step 513: The MSC/VLR, the UE completes the remaining called establishment process.

After receiving the location update (LU) request message of the SGs interface, the MSC/VLR transfers the paging from the circuit switched network to the LTE network, which improves the call completion rate and makes the network service more satisfactory. .

FIG. 7 is a schematic diagram of an MSC according to an embodiment of the present invention. As shown in FIG. 7, the MSC in this embodiment includes: a first paging module, a determining module, and a second paging module, where

The first paging module 701 is configured to: after receiving the called service request, initiate a paging to the terminal in the circuit domain switching network;

The determining module 702 is configured to: determine, in the paging process, whether the terminal has been transferred to the system architecture evolution network, and if yes, notify the second paging module;

The second paging module 703 is configured to: after receiving the notification of the determining module, the terminal is called by the interface SGs interface between the mobility management entity MME and the mobile switching center MSC.

The determining module 702 is configured to determine whether the terminal has been transferred to the system architecture evolution network by: if receiving the location update request message of the SGs interface, determining that the terminal has transferred to the system architecture evolution network.

One of ordinary skill in the art will appreciate that all or a portion of the above steps may be accomplished by a program instructing the associated hardware, such as a read-only memory, a magnetic disk, or an optical disk. Alternatively, all or part of the steps of the above embodiments may also be implemented using one or more integrated circuits. Correspondingly, each module/unit in the above embodiment may be implemented in the form of hardware or in the form of a software function module. The invention is not limited to any specific form of combination of hardware and software.

The above is only a preferred embodiment of the present invention, and of course, the present invention may be embodied in various other embodiments without departing from the spirit and scope of the present invention. Various changes and modifications may be made to the invention, but such changes and modifications are intended to be included within the scope of the appended claims.

Industrial applicability

The embodiment of the invention provides a paging method and a mobile switching center, which allows the MSC/VLR to increase the paging of the SGs interface during the paging process of the circuit domain, thereby solving the paging failure problem caused by the UE roaming between different networks. The success rate of the called service of the UE in the hybrid network of the circuit domain switching network and the SAE network is increased. Therefore, it has strong industrial applicability.

Claims

claims

1. A paging method, including:

After receiving the called service request, the mobile switching center MSC or the visited location register VLR initiates paging to the terminal in the circuit domain switching network; and

During the paging process, it is determined whether the terminal has been transferred to the system architecture evolution network. If so, the MSC or VLR paging the terminal through the SGs interface between the mobility management entity MME and the MSC.

2. The paging method according to claim 1, wherein: the step of determining whether the terminal has been transferred to the system architecture evolution network includes:

If the MSC or VLR receives the location update request message of the SGs interface, it is determined that the terminal has been transferred to the system architecture evolution network.

3. The paging method according to claim 1 or 2, wherein: the system architecture evolution network includes:

Long Term Evolution or Evolved Packet Core Network.

4. A mobile switching center, including: a first paging module, a judgment module and a second paging module, wherein,

The first paging module is configured to: after receiving the called service request, initiate paging to the terminal on the circuit domain switching network;

The determination module is configured to: during the paging process, determine whether the terminal has been transferred to the system architecture evolution network, and if so, notify the second paging module; and

The second paging module is configured to: after receiving the notification from the judgment module, page the terminal through the interface SGs interface between the mobility management entity MME and the mobile switching center MSC.

5. The mobile switching center as claimed in claim 4, wherein:

The determination module is configured to determine whether the terminal has been transferred to the system architecture evolution network in the following manner: if the location update request message of the SGs interface is received, it is determined that the terminal has been transferred to the system architecture evolution network.

6. The mobile switching center according to claim 4 or 5, wherein: the system architecture evolution network includes:

Long Term Evolution or Evolved Packet Core Network.