WO2012103835A2

WO2012103835A2 - Call connection method, device and system

Info

Publication number: WO2012103835A2
Application number: PCT/CN2012/072825
Authority: WO
Inventors: 王新勇; 周敬华; 朱浩鹏; 姜涛
Original assignee: 华为技术有限公司
Priority date: 2012-03-22
Filing date: 2012-03-22
Publication date: 2012-08-09
Also published as: CN103416092A; WO2012103835A3

Abstract

An embodiment of the present invention provides a call connection method, comprising: a CSFB Proxy configuring a correlation table of the location area identifier (LAI) and the visited mobile switch center (VMSC) number; receiving a combined location update request message sent by a mobile management entity (MME), and determining, according to an LAI carried in the request message, a VMSC number corresponding to the LAI; constructing a Provide Roaming Number (PRN) request message, the VMSC number being encapsulated into the PRN request message; and sending the PRN request message to a determined VMSC to trigger the VMSC to initiate a data recovery process to obtain user data, so that upon receiving a call request, the VMSC establishes a call path according to the user data to complete call connection. Accordingly, embodiments of the present invention further provide a CSFB Proxy, a VMSC, and a call connection system, thereby reducing steps of the call process and the call delay and improving the user experience.

Description

Method, device and system for call connection

Technical field

The embodiments of the present invention relate to the field of communications technologies, and in particular, to a method, device, and system for call connection. Background technique

In the development of Long Term Evolution (LTE), the voice service of LTE terminals also needs a long transition period. During the transition period, voice services need to evolve from the UMTS terrestrial radio access network (Evolved UMTS Temtoiial). Radio Access Network, E-UTRAN) returns GSM EDGE Radio Access Network (GERAN) / UMTS Territorial Radio Access Network (UMTS Territorial Radio Access Network,

The CSFB function requires the upgrade of the current network end office and the gateway office to support it. The CSFB proxy (CSFB Proxy) entity networking scheme can implement the voice call fallback function of the terminal attached to the E-UTRAN without affecting the existing network equipment.

In the prior art, based on the CSFB Proxy networking scenario, the terminal attached to the E-UTRAN initiates an active call in the CS domain after the CSFB operation is performed, and the visited mobile switching center (VMSC) receives the user. When a call is initiated by a device (User Equipment, UE), since there is no user data, a location update process to the Home Location Register (HLR) needs to be initiated, and there is a large delay relative to the standard active call flow. In addition, the terminal initiates a passive call flow after the CSFB is back, and the VMSC also needs to initiate the call to the HLR. During the location update process, after completing the location update process, the HLR sends a Cancel Location message to the CSFB Proxy, triggering the CSFB Proxy to complete the mobile terminated call roaming re-call process, and needs to interact with the HLR and complete the secondary routing process. Therefore, in the prior art, in the CSFB Proxy networking scenario, there is a large delay in both the calling and the called in the CS domain, and the user experience is low.

Summary of the invention

The embodiment of the invention provides a method, a device and a system for the call connection, which solves the problem that the delay of the voice service in the CSFB Proxy networking scenario is large in the prior art.

The embodiment of the invention provides a method for call connection, including:

The circuit domain fallback proxy CSFB Proxy receives the joint location update request message sent by the mobility management entity MME;

Determining, according to the location area identifier LAI carried in the request message, the visited mobile switching center VMSC number corresponding to the LAI;

Sending a provisioning roaming number PRN request message carrying the VMSC number to the determined VMSC, triggering the VMSC to initiate a data recovery process, so that the VMSC obtains user data, so that the VMSC receives the user data after obtaining the user data. When the call is requested, a call path is established according to the user data, and the call connection is completed.

The embodiment of the present invention further provides a circuit domain fallback proxy CSFB Proxy, including: a receiving unit, configured to receive a joint location update request cancellation determining unit sent by the mobility management entity MME, configured to use the location area identifier carried in the request message LAI, determining a VMSC number of the visited mobile switching center corresponding to the LAI; a sending unit, configured to send a PRN request message carrying the VMSC number to the determined VMSC, triggering the VMSC to initiate a data recovery process, so that the VMSC obtains user data, so that the VMSC after obtaining the user data When the call request is received, a call path is established according to the user data, and the call connection is completed.

The embodiment of the invention further provides a VMSC, including:

a receiving unit, configured to receive a PRN request cancellation triggering unit sent by the circuit domain fallback proxy CSFB Proxy, to trigger a data recovery process according to the PRN request message received by the receiving unit;

An obtaining unit, configured to obtain user data after the trigger unit triggers a data recovery process;

The calling unit is configured to establish a call path according to the user data when the call request is received, and complete the call connection.

The embodiment of the present invention further provides a call connection system, including a CSFB Proxy and a VMSC, where

The CSFB Proxy is configured to receive a location update request message sent by the mobility management entity MME, determine a VMSC number of the visited mobile switching center corresponding to the LAI, and send the VMSC according to the location area identifier LAI carried in the request message. a PRN request message of the number to the determined VMSC, triggering the VMSC to initiate a data recovery process to obtain user data, so that the VMSC establishes a call according to the user data when receiving a call request after obtaining the user data. Path, complete call connection;

The VMSC is configured to receive a PRN request message sent by a CSFB Proxy, and trigger data. The recovery process obtains user data, and upon receiving the call request, establishes a call path according to the user data, and completes the call connection.

Through the method, the device and the communication system provided by the embodiment of the present invention, the CSFB Proxy constructs a PRN request message to be sent to the corresponding VMSC, triggers the VMSC data recovery, reduces the call flow step, reduces the call delay, and improves the user experience.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings to be used in the embodiments or the description of the prior art will be briefly described below, and obviously, the attached in the following description The drawings are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

1 is a flowchart of a method according to Embodiment 1 of the present invention;

2 is a flowchart of a calling party according to Embodiment 2 of the present invention;

3 is a flow chart of a called party according to Embodiment 3 of the present invention;

4 is a structural diagram of CSFB Pr oxy according to Embodiment 4 of the present invention;

5 is a structural diagram of a VMSC according to Embodiment 5 of the present invention;

FIG. 6 is a structural diagram of a system according to Embodiment 6 of 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. Based on the embodiments of the present invention, those skilled in the art will not All other embodiments obtained are considered to be within the scope of the invention.

Embodiment 1 of the present invention:

FIG. 1 is a flowchart of a method for a call connection according to the present invention. As shown in FIG. 1, the method may include:

S101. The CSFB Proxy receives a joint location update request message sent by a mobility management entity (Mobility Management Entity, ΜΜΕ);

In the embodiment of the present invention, the joint location update request message is specifically: a combined routing area/location area update request message (Combined RAU/LAU Request) or a combined tracking area/location area update request message ( Combined TAU/LAU Request). Taking the combined routing area/location area update message as an example, the cell update type carried in the message is set to "Combined RA/LA Updating". The message carries a cell "MS network capability", which is used to indicate the network capability of the terminal. The cell "MS network capability" has an entry "EMM Combined procedures capability", which is used to indicate the UE's ability to support the joint process related to mobility management. If the UE supports the above joint process, the "EMM Combined procedures capability" is assigned a value of 1, and conversely, the value is 0. Whether it is a joint routing area/location area update request message or a joint tracking area/location area update request message, the message needs to carry a Location Area Identity (LAI).

Before receiving the joint location update request message sent by the MME, the CSFB Proxy also needs to configure a correspondence table between the LAI and the VMSC number. The corresponding relationship between the LAI and the VMSC may be that multiple LAIs correspond to one VMSC.

S102. Determine, according to the location area identifier LAI carried in the request message, a VMSC number of the visited mobile switching center corresponding to the LAI. The CSFB Proxy receives the joint location update request sent by the MME, obtains the LAI of the terminal, and queries the correspondence table between the LAI and the VMSC number to obtain the corresponding VMSC number.

The VMSC number is an identifier of the VMSC, usually a string of numbers. The VMSC address is known by the VMSC number. In the embodiment of the present invention, after acquiring the VMSC number, the CSFB Proxy can communicate with the corresponding VMSC.

S103. Send a Provide Roaming Number (PRN) request message carrying the VMSC number to the determined VMSC, and trigger the VMSC to initiate a data recovery process, so that the VMSC obtains user data, so that the VMSC is in the When the call request is received after the user data is obtained, a call path is established according to the user data, and the call connection is completed.

Specifically, after obtaining the VMSC number, the CSFB Proxy constructs a PRN request message and encapsulates the VMSC number into the PRN request message. PRN request message may be constructed according to the basic format of a voice call, in the embodiment of the present invention, including but not limited PRN request message to the international mobile subscriber identity ¹ J another code (International Mobile Subscriber Identity, IMSI) numbers, and VMSC.

After the PRN request message is constructed, the PRN request message is sent to the corresponding VMSC according to the obtained VMSC number, to trigger the VMSC to initiate a data recovery process.

It should be noted that if the CSFB Proxy has saved the VMSC number before obtaining the VMSC number, assuming that the number is A, the VMSC number obtained by checking the correspondence table according to the LAI is B. Before constructing a PRN message, the CSFB Proxy also needs to make a judgment based on the relationship between A and B, as follows:

1) If A is judged to be invalid, the CSFB Proxy initiates the construction of the PRN process according to the number B; The specific discriminating method may be: setting a default value. In the embodiment of the present invention, there is no specific requirement for setting the default value, and may be a hexadecimal "FFFF" or another value, if the number A is equal to the default value. , it is judged that the number A is invalid, and if the number A is not equal to the default value, it is judged that the number A is valid. In addition, in the CSFB Proxy initialization state, the number A is set to the default value.

When the first correspondence check table obtains the number B, the number A is the set default value, the judgment number A is invalid, and after the PRN process is initiated, the CSFB Proxy updates the value of the number A saved by itself to the number B.

2) Judging that A is a valid value, but A is not equal to B, the CSFB Proxy takes the number B obtained by the look-up table as the standard, and initiates the construction of the PRN process according to the number B;

After constructing the PRN process, CSFB Proxy updates the value of its saved number A to number B.

3) If A is judged to be a valid value and A is equal to B, then the CSFB Proxy has already initiated the process of constructing a PRN message, and does not need to initiate the process of constructing a PRN message again.

After receiving the PRN request message, the VMSC returns a PRN response message carrying the Mobile Service Roaming Number (MSRN) to the CSFB Proxy, and initiates a data recovery process, specifically: sending a data request message to the HLR, and the HLR sends User data information to the VMSC.

After the VMSC completes the data recovery process, the CSFB Proxy needs to release the MSRN. The CSFB Proxy release MSRN can be released through the standard MAP RELEASE RESOURCE process. The CSFB Proxy sends a MAP RELEASE RESOURCE request to the VMSC. After receiving the VMSC, the VMSC releases the allocated MSRN and returns the MAP. RELEASE RESOURCE response message to CSFB Proxy.

It should be noted that the call request has two modes: active call and passive call.

Active call: After the MSRN is released, the extended service request sent by the terminal is sent to the MME. The MME instructs the terminal to perform a circuit domain fallback (CSFB) operation. After performing the CSFB operation, the terminal initiates an active call request to the VMSC in the CS domain.

After receiving the active call request, the VMSC has obtained the user data by initiating the data recovery process. Therefore, after receiving the active call request of the terminal, the VMSC does not need to initiate an update interaction process with the HLR to obtain user data, thereby reducing the steps of the standard process. . After the user data is authenticated, encrypted, and checked by the International Mobile Equipment Identity (IMEI), a call path is established with the terminal to complete the call operation between the terminal and the VMSC.

Passive call: The called process of the CS domain is the process of communication from the GMSC end office to the VMSC end office. In the CSFB Proxy networking, you need to access the CSFB Proxy from the GMSC and then connect to the VMSC from the CSFB Proxy. When there is a passive call, the GMSC first sends the SRI to the HLR to obtain the MSRN, and communicates with the CSFB Proxy according to the MSRN.

After receiving the passive call from the CS domain, the HLR sends a PRN message to the CSFB Proxy; the HLR sends a PRN message to the corresponding CSFB Proxy according to the CSFB Proxy number to obtain the MSRN. After receiving the PRN message sent by the HLR, the CSFB Proxy allocates the MSRN, encapsulates the MSRN into the PRN response message, and sends a PRN response message to the HLR. The HLR returns an SRI acknowledgment message to the GMSC, and the message carries the MSRN. After receiving the SRI acknowledgment message, the GMSC sends the IAM to the CSFB Proxy corresponding to the MSRN. CSFB Proxy selects the saved VMSC number The code is used as the target VMSC. The CRFB message sent by the HLR carries the number of the CSFB Proxy. Therefore, the CSFB Proxy number carried by the PRB is replaced by the VMSC number obtained by the lookup table, and the PRN message is transparently transmitted to the target VMSC.

The VMSC returns a PRN response message to the CSFB Proxy. The PRN response message carries the MSRN allocated by the VMSC. The MSRN is different from the MSRN allocated by the CSFB Proxy. To indicate the MSRN2, the MSRN is used to indicate the MSRN.

After receiving the PRN response message, the CSFB Proxy sends an IAM message to the VMSC, where the IAM message carries the MSRN2. At the same time, the CSFB Proxy sends a paging message to the MME, and the MME instructs the terminal to complete the CSFB operation.

After completing the CSFB operation, the terminal establishes a call path with the VMSC to complete the called operation. It should be noted that, in the standard joint location update process under the CSFB Proxy networking structure, the VMSC does not initiate a data recovery process, that is, the VMSC does not save the user data information, so the VMSC needs to perform with the HLR in the standard passive call procedure. Location update interaction, getting user data. In addition, after the location update process, the HLR also needs to send a Cancel Location message to the CSFB Proxy to enable the CSFB Proxy to delete the user data and trigger the CSFB Proxy to initiate the Mobile Terminate Roaming Retry (MTRR) process. In this process, a secondary route is required, specifically: the CSFB Proxy sends the SRI to the HLR, and the HLR interacts with the VMSC to obtain the MSRN2 allocated by the VMSC, and then sends the MSRN2 to the CSFB Proxy.

Therefore, after the terminal completes the CSFB operation, the call response is sent to the VMSC. Since the VMSC saves the user data information, the VMSC does not need to perform location update interaction with the HLR to acquire user data, and the CSFB Proxy is no longer required to initiate the MTRR process. , cut back The steps of the standard called process.

The CSFB Proxy constructs a PRN request message to the corresponding VMSC, which triggers the VMSC data recovery, reduces the call flow procedure, reduces the call delay, and improves the user. Experience.

Embodiment 2 of the present invention:

As shown in FIG. 2, in this embodiment, the calling process after the location area is updated and updated is as follows:

S201, CSFB Proxy configuration table of correspondence between LAI and VMSC numbers;

In the CSFB Proxy, you need to configure the LAI of the terminal and the corresponding VMSC number information. Usually, one VMSC number corresponds to at least one LAI.

It should be noted that, in the MSC pool scenario, each MSC saves the same LAI information, and at least one MSC needs to be determined as the target VMSC.

S202. The Mobility Management Entity (MME) initiates a joint location update request to the CSFB Proxy.

In the embodiment of the present invention, the joint location update request message is specifically: a combined routing area/location area update request message ( Combined RAU/LAU Request) or a combined tracking area/location area update request message ( Combined TAU/LAU Request). Taking the joint routing area/location area update message as an example, the cell update type carried in the message is set to "Combined RA/LA Updating". The message carries a cell "MS network capability", which is used to indicate the network capability of the terminal. Among them, the cell "MS network capability" There is an entry "EMM Combined procedures capability", which is used to indicate the UE's ability to support the joint process of mobility management. If the UE supports the above joint procedure, the "EMM Combined procedures capability" is assigned a value of 1 and vice versa. Whether it is a joint routing area/location area update request message or a joint tracking area/location area update request message, the message needs to carry a Location Area Identity (LAI).

It should be noted that the MME sends a joint location update request to the CSFB Proxy through the SGs association interface, where the message carries the LAI of the terminal attached to the MME.

5203. The CSFB Proxy completes a location update interaction process with the HLR.

During this process, the CSFB Proxy sends a location update request message to the HLR. After receiving the message, the HLR performs data interaction with the CSFB Proxy. After the interaction is completed, the HLR returns a MAP location update confirmation message to the CSFB Proxy, and the process ends.

After the interaction process is completed, the HLR saves the CSFB Proxy number, and the CSFB Proxy gets the user data. The user data is information for the user to open an account.

5204, CSFB Proxy returns a location update accept message to the MME;

The location update accept message carries a Temporary Mobile Subscriber Identifier (TMSI).

It should be noted that, in the MSC pool scenario, the location update accept message also needs to carry a Network Resource Identifier (NRI), which is used to determine the MSC corresponding to the NRI and the backup MSC as the target VMSC.

S205, the CSFB Proxy obtains the VMSC number according to the LAI, and constructs a Provide Roaming Number (PRN) request message to be sent to the VMSC;

In S202, the CSFB Proxy receives the joint location update request sent by the MME, and obtains The LAI of the terminal, querying the correspondence table between the LAI and the VMSC number, obtains the corresponding VMSC number. After obtaining the VMSC number, a PRN request message is constructed and the VMSC number is encapsulated into a PRN request message. The PRN request message may be configured according to a basic voice call format. In the embodiment of the present invention, the PRN request message includes, but is not limited to, an International Mobile Subscriber Identity (IMSI) and a VMSC number.

It should be noted that if the CSFB Proxy has saved the VMSC number before obtaining the VMSC number, assuming that the number is A, the VMSC number obtained according to the LAI lookup table is B. Before constructing a PRN message, the CSFB Proxy also needs to make a judgment based on the relationship between A and B, as follows:

1) The AFB is determined to be an invalid value, and the CSFB Proxy initiates the construction of the PRN process according to the number B. The specific discriminating method may be: setting a default value. In the embodiment of the present invention, there is no specific requirement for setting the default value, which may be 16 The system "FFFF" can also be another value. If the number A is equal to the default value, the number A is judged to be invalid. If the number A is not equal to the default value, the number A is determined to be valid. In addition, in the CSFB Proxy initialization state, the number A is set to the default value.

When the first lookup table obtains the number B, the number A is the set default value, the judgment number A is invalid, and after the PRN process is initiated, the value of the update number A is the number B.

After constructing the PRN process, the number A is updated to the number B. 3) If A is judged to be a valid value, and A is equal to B, it is considered that the CSFB Proxy has initiated the process of constructing a PRN message, and does not need to initiate the process of constructing a PRN message again.

S206a, the VMSC returns a PRN response message;

The VMSC allocates a Mobile Service Roaming Number (MSRN) and encapsulates the MSRN to send a PRN response message to the CSFB Proxy in the PRN response message.

S206b, the VMSC initiates a data recovery process;

After receiving the PRN request message, the VMSC returns a PRN response message carrying the MSRN to the CSFB Proxy, and initiates a data recovery process, specifically: sending a data request message to the HLR, and the HLR sends the user data information to the VMSC.

5207, CSFB Proxy saves VMSC number, VMSC releases allocated MSRN; CSFB Proxy releases MSRN can release resources through standard mobile application (MAP

The RELEASE RESOURCE process is released. Specifically, the CSFB Proxy sends a MAP RELEASE RESOURCE request to the VMSC. After receiving the VMSC, the VMSC releases the allocated MSRN and returns a MAP RELEASE RESOURCE response message to the CSFB Proxy.

5208. The MME instructs the terminal to perform a CSFB operation.

Steps S201-S207 are processes of the entire joint location update in the embodiment of the present invention. After the joint location update process is completed, the terminal sends an extended service request to the MME, and after receiving the extended service request, the MME instructs the terminal to perform a CSFB operation.

5209. The terminal initiates an active call request to the VMSC.

After performing the CSFB operation, the terminal initiates an active call request to the VMSC in the CS domain.

5210. The VMSC establishes an active call path, and completes a call operation between the terminal and the VMSC. In S206b, the VMSC triggers the data recovery process and obtains the user data. Therefore, after receiving the active call request of the terminal, the VLR does not need to initiate an update interaction process with the HLR to acquire user data, thereby reducing the steps of the standard process. After the user data is authenticated, encrypted, and checked by the International Mobile Equipment Identity (IMEI), a call path is established with the terminal to complete the call operation between the terminal and the VMSC.

The method for reducing the delay in the CSFB Proxy networking structure provided by this embodiment, the CSFB Proxy constructs a PRN request message to be sent to the corresponding VMSC, triggers the VMSC data recovery, reduces the active call process steps, reduces the active call delay, and improves The user experience. Embodiment 3 of the present invention:

In this embodiment, as shown in FIG. 3, the terminal performs the process of updating the location area and the called party as follows: S301—S307 and S201—S207;

5308. The GMSC sends a Routing Information (SRI) to the HLR. The called process in the CS domain is a process in which the Gate MSC (GMSC) end office communicates with the VMSC end office. In the CSFB Proxy networking, you need to access the CSFB Proxy from the GMSC and then connect to the VMSC from the CSFB Proxy.

Steps S301-S307 are processes of the entire joint location update in the embodiment of the present invention. After the joint location update process is completed, when a passive call occurs, the GMSC first sends the SRI to the HLR to obtain the MSRN, and communicates with the CSFB Proxy according to the MSRN.

5309. The HLR sends a PRN message to the CSFB Proxy.

The acquisition of MSRN requires the interaction of the HLR with the CSFB Proxy. In step S303, the HLR obtains the number of the CSFB Proxy, and the HLR sends a PRN message to the corresponding CSFB Proxy according to the number of the CSFB Proxy to obtain the MSRN. S310, CSFB Proxy allocates MSRN, and returns a PRN response message to the HLR;

After receiving the PRN message sent by the HLR, the CSFB Proxy allocates the MSRN and encapsulates the MSRN to PRN response message, and sends a PRN response message to the HLR.

S311. The HLR returns an SRI acknowledgement message to the GMSC, where the message carries the MSRN.

5312. The GMSC sends the IAM to the CSFB Proxy.

After receiving the SRI acknowledgement message carrying the MSRN, the GMSC sends the IAM to the CSFB Proxy corresponding to the MSRN.

5313. The CSFB Proxy transparently transmits the PRN message sent by the HLR to the VMSC.

The CSFB Proxy determines the saved VMSC number as the target VMSC and transparently transmits the PRN message sent by the HLR to the target VMSC.

5314. The VMSC returns a PRN response message to the CSFB Proxy.

The PRN response message carries the MSRN allocated by the VMSC. The MSRN is different from the MSRN allocated by the CSFB Proxy in S310. To distinguish the MSRN, the MSRN is used to indicate the MSRN.

S315a, CSFB Proxy sends an IAM message to the VMSC;

The IAM message carries the MSRN2.

S315b, CSFB Proxy sends a paging message to the MME;

The passive call of the CS domain requires the terminal to complete the call connection in the CS domain, but the terminal is attached to the MME, and the CSFB Proxy sends a paging message to the MME, so that the MME instructs the terminal to complete the CSFB operation.

5316. The MME instructs the terminal to complete the CSFB operation.

5317. The terminal establishes a call path with the VMSC to complete the called operation.

It should be noted that due to the standard joint location under the CSFB Proxy networking structure, In the new process, the VMSC does not initiate the data recovery process, that is, the VMSC does not save the user data information. Therefore, during the standard passive call process under the CSFB Proxy networking structure, the VMSC needs to perform location update interaction with the HLR to acquire user data. Moreover, after the location update process, the HLR also needs to send a cancel location message to the CSFB Proxy, so that the CSFB Proxy deletes the user data, triggering the CSFB Proxy to initiate a Mobile Terminate Roaming Retry (MTRR) process. In this process, a secondary route is required, specifically: the CSFB Proxy sends the SRI to the HLR, and the HLR interacts with the VMSC to obtain the MSRN2 allocated by the VMSC, and then sends the MSRN2 to the CSFB Proxy.

After the terminal completes the CSFB operation, the VMSC sends a paging message to the terminal. After receiving the paging message sent by the VMSC, the terminal sends a paging response message to the VMSC. Since the VMSC saves the user data information, the VMSC does not need to perform location update interaction with the HLR to acquire user data, and CSFB is no longer needed. The Proxy initiates the MTRR process, which reduces the steps of the standard called process.

The CSFB Proxy constructs a PRN request message to be sent to the corresponding VMSC, which triggers the VMSC data recovery, reduces the passive call flow, and solves the problem of large passive call delay. , improved user experience. Embodiment 4 of the present invention:

An embodiment of the present invention provides a circuit domain fallback proxy (CSFB Proxy), as shown in FIG. 4, including:

The receiving unit 401 is configured to receive a joint location update request message sent by the mobility management entity.

The joint location update request message is specifically in the embodiment of the present invention: a joint routing area/bit Combined RAU/LAU Request or a combined tracking area/location area update request message ( Combined TAU/LAU Request). Taking the joint routing area/location area update message as an example, the cell update type carried in the message is set to "Combined RA/LA Updating". The message carries a cell "MS network capability", which is used to indicate the network capability of the terminal. The cell "MS network capability" has an entry "EMM Combined procedures capability", and the entry is used to indicate the capability of the UE to support the joint process related to mobility management. If the UE supports the above joint procedure, the "EMM Combined procedures capability" is assigned a value of 1 and vice versa. Whether it is a joint routing area/location area update request message or a joint tracking area/location area update request message, the message needs to carry a Location Area Identity (LAI). In addition, the CSFB Proxy further includes a configuration unit configured to configure a mapping table between the location area identifier LAI and the visited mobile switching center VMSC number. The corresponding relationship between the LAI and the VMSC may be that multiple LAIs correspond to one VMSC.

The determining unit 402 is configured to determine, according to the LAI carried in the request message, a VMSC number corresponding to the LAI;

After the receiving unit 401 receives the joint location update request sent by the MME, the determining unit 402 obtains the LAI of the terminal, and determines the corresponding VMSC number according to the LAI and VMSC number correspondence table.

The sending unit 403 sends a PRN request message carrying the VMSC number to the determining The VMSC triggers the VMSC to initiate a data recovery process, so that the VMSC obtains user data, so that when the VMSC receives the call request after obtaining the user data, the VMSC establishes a call path according to the user data, and completes the call connection.

After the determining unit 402 determines the VMSC number, the CSFB Proxy's construction unit constructs a PRN request message and encapsulates the VMSC number into the PRN request message. The constructing unit may construct the PRN request message according to the basic voice call format. In the embodiment of the present invention, the PRN request message includes but is not limited to an International Mobile Subscriber Identity (IMSI) and a VMSC number.

After the PRN request message is constructed, the sending unit 403 sends the PRN request message to the corresponding VMSC according to the obtained VMSC number, to trigger the VMSC to initiate a data recovery process.

It should be noted that, if the determining unit 402 has saved the VMSC number before determining the VMSC number, assuming that the number is A, the determining unit 402 determines that the VMSC number is B. Before constructing the PRN message, the judgment unit also needs to make a judgment based on the relationship between A and B, as follows:

1) The judging unit judges that A is an invalid value, and the constructing unit initiates constructing a PRN process according to the number B;

The determining unit sets a default value. In the embodiment of the present invention, there is no specific requirement for setting the default value, which may be hexadecimal "FFFF" or other value. If the number A is equal to the default value, the number is determined. A is invalid. If the number A is not equal to the default value, it is judged that the number A is valid. Also, in the CSFB Proxy initialization state, the number A is set to the default value.

When the determining unit 402 first determines the number B, the number A is the set default value. Then, the judging unit judges that the number A is invalid, and after initiating the construction of the PRN process, the constructing unit updates the value of the number A saved by itself to the number B.

2) The judging unit judges that A is a valid value, but A is not equal to B, and the constructing unit 404 initiates constructing a PRN process according to the number B determined by the determining unit 403;

Construction unit construction After the PRN process, update the value of the number A saved by itself to the number

B.

3) The judging unit judges that A is a valid value, and A is equal to B, then the judging unit thinks that the constructing unit has constructed the PRN request message, so the notification constructing unit does not need to construct the PRN request to cancel the call request as a passive call, and the HLR sends the CSFB. After receiving the PRN message of the Proxy number to the CSFB Proxy, the receiving unit 401 of the CSFB Proxy receives the PRN message sent by the HLR, and the replacement unit replaces the CSFB Proxy number carried by the PRN with the VMSC number determined by the determining unit 402, and passes the sending unit 403. The PRN message is transparently transmitted to the target VMSC.

The VMSC returns a PRN response message to the receiving unit 401 of the CSFB Proxy. After receiving the response message, the receiving unit 401 sends a call message to the MME through the sending unit 403 of the CSFB Proxy, and the MME instructs the terminal to complete the CSFB operation.

After completing the CSFB operation, the terminal establishes a call path with the VMSC to complete the called operation. After the terminal completes the CSFB operation, the call response is sent to the VMSC. Since the VMSC has obtained the user data by initiating the data recovery process before receiving the active call request, the VMSC receives the active call request of the terminal, so the VMSC does not need to The location update interaction with the HLR is used to obtain user data, and the CSFB Proxy is no longer required to initiate the MTRR process, which reduces the steps of the standard called process. In the CSFB Proxy provided by the embodiment, the determining unit 402 determines the corresponding VMSC number, the constructing unit constructs the PRN message, and encapsulates the VMSC number into the PRN request message, and the sending unit 403 sends the PRN message constructed by the constructing unit to the corresponding VMSC, triggering the VMSC. Data recovery reduces the number of process steps for calls, reduces call delays, and improves the user experience.

Embodiment 5 of the present invention:

An embodiment of the present invention provides a visited mobile switching center (VMSC), as shown in FIG. 5, including:

The receiving unit 501 is configured to receive a PRN request message sent by the CSFB Proxy, where the PRN request message sent by the CSFB Proxy carries the VMSC number.

The triggering unit 502 is configured to trigger a data recovery process according to the PRN request message received by the receiving unit 501.

After the receiving unit 501 receives the PRN request message, the triggering unit 502 triggers the data recovery process, specifically: sending a data request message to the HLR, and the HLR sends the user data information to the VMSC.

The obtaining unit 503 is configured to obtain user data after the triggering unit 502 triggers the data recovery process;

After the trigger unit 502 triggers the data recovery process, the obtaining unit 503 acquires the user data transmitted by the HLR.

The calling unit 504 is configured to establish a call path according to the user data acquired by the acquiring unit when receiving the call request, and complete the call connection.

When the call request is an active call, after the MSRN is released, the extended service request sent by the terminal is sent to the MME, and the MME instructs the terminal to perform the CSFB operation. After the CSFB operation is performed, the terminal An active call request is initiated to the VMSC in the CS domain.

After receiving the active call request of the terminal, the calling unit 504 does not need to initiate an update interaction process with the HLR to acquire user data, which reduces the steps of the standard process. After the user unit is authenticated, encrypted, and checked by the International Mobile Equipment Identity (IMEI), the calling unit 504 establishes a call path with the terminal to complete the call operation between the terminal and the VMSC.

In the VMSC provided by the embodiment, after receiving the PRN request message sent by the CSFB Proxy, the receiving unit triggers the VMSC data recovery, reduces the call flow step, reduces the call delay, and improves the user experience.

Embodiment 6 of the present invention:

The embodiment of the present invention further provides a call connection system, as shown in FIG. 6, including: a circuit domain fallback proxy (CSFB Proxy) 601, configured to receive a joint location update request message sent by the MME, and carry the message according to the request message. And determining, by the LAI, the VMSC number corresponding to the LAI, sending a PRN request message carrying the VMSC number to the determined VMSC, triggering the VMSC to initiate a data recovery process to obtain user data, so that the VMSC obtains the location When the call request is received after the user data is described, a call path is established according to the user data, and the call connection is completed;

It should be noted that, before receiving the location update request message sent by the MME, the CSFB Proxy configures a correspondence table between the LAI and the VMSC number. After obtaining the LAI, the corresponding VMSC number is determined by checking the correspondence table.

In addition, the CSFB Proxy also needs to construct a PRN request message and encapsulate the VMSC number into the PRN request message. In the embodiment of the present invention, the PRN can be performed according to the basic voice format. Request a message for construction.

If the CSFB Proxy has saved the VMSC number before obtaining the VMSC number, assuming that the number is A, the VMSC number obtained by checking the correspondence table after LAI is B. Before constructing a PRN message, the CSFB Proxy also needs to make a judgment based on the relationship between A and B, as follows:

1) The AFB is determined to be an invalid value, and the CSFB Proxy initiates the construction of the PRN process according to the number B. The specific discriminating method may be: setting a default value. In the embodiment of the present invention, there is no specific requirement for setting the default value, which may be 16 The system "FFFF" can also be another value. If the number A is equal to the default value, the number A is judged to be invalid. If the number A is not equal to the default value, the number A is determined to be valid. Also, in the CSFB Proxy initialization state, the number A is set to the default value.

After constructing the PRN process, update the number A to the number B.

After the judgment is completed, the construct PRN request message can construct the PRN request message in accordance with the voice call message format. The PRN request message includes but is not limited to the International Mobile Subscriber Identity (IMSI) and the VMSC number.

Visiting a Mobile Switching Center (VMSC) 602 for receiving a PRN sent by a CSFB Proxy The request message triggers the data recovery process to obtain the user data. When the call request is received, the call path is established according to the user data, and the call connection is completed.

With the system provided in this embodiment, the CSFB Proxy constructs a PRN request message and sends it to the VMSC, triggering the VMSC to initiate a data recovery process, reducing the call flow step, reducing the call delay, and improving the user experience.

It can be clearly understood by those skilled in the art that, for the convenience and the cleaning of the description, the specific working processes of the system, the device and the unit described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be further described herein.

It will be understood by those of ordinary skill in the art that the drawings are only a schematic representation of one embodiment, and the elements or processes in the drawings are not necessarily required to practice the invention.

In the several embodiments provided herein, it should be understood that the disclosed systems, devices, and methods may be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not executed. Alternatively, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in electrical, mechanical or other form. The components displayed as units may or may not be physical units, i.e., may be located in one place, or may be distributed over multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, each functional unit in various embodiments of the present invention may be integrated into one processing unit In addition, each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of hardware plus software functional units.

The above-described integrated unit implemented in the form of a software functional unit can be stored in a computer readable storage medium. The above software functional units are stored in a storage medium and include a number of steps for causing a computer device (which may be a personal computer, server, or network device, etc.) to perform the methods of the various embodiments of the present invention. The foregoing storage medium includes: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, and the like. The medium of the program code.

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 call connection, characterized in that it comprises:

The method according to claim 1, wherein before the receiving the location update request message sent by the MME, the method further includes:

Configure the mapping between the location area identifier LAI and the visited mobile switching center VMSC number.

The method according to claim 1 or 2, wherein before the sending the PRN request message carrying the VMSC number to the determined VMSC, the method further includes:

Constructing a roaming number PRN request message, encapsulating the VMSC number into the PRN request message.

4. The method of claim 3, wherein constructing a roaming number PRN request message comprises:

The PRN request message is constructed in accordance with a voice call message format.

The method according to claim 4, wherein before the constructing the PRN request message, the method further includes: If the saved VMSC number is equal to the set default value, it is determined that the VMSC number is invalid, and if the saved VMSC number is not equal to the set default value, it is determined that the VMSC number is valid;

If the saved VMSC number is not equal to the determined VMSC number, the CSFB Proxy constructs the PRN request message.

The method according to any one of claims 1 to 5, wherein the VMSC initiates a data recovery process, including:

Sending a data request message to the home location register HLR;

Receive user data sent by the HLR.

The method according to any one of claims 1 to 5, wherein, when the call is a circuit-switched CS domain passive call, before the VMSC establishes a call path according to the user data, the method further includes:

The CSFB Proxy receives the PRN message sent by the HLR, and the PRN message sent by the HLR carries the CSFB Proxy number;

And replacing the CSFB Proxy number with the VMSC number according to the saved VMSC number, and transparently transmitting the PRN message sent by the HLR to the VMSC;

Receiving a PRN response message sent by the VMSC, and sending the CS domain passive call response message to the mobility management entity MME, so that the MME instructs the corresponding terminal to perform a CSFB operation.

8. A circuit domain fallback agent CSFB Proxy, characterized in that:

a receiving unit, configured to receive a joint location update request cancellation determining unit sent by the mobility management entity MME, configured to determine, according to the location area identifier LAI carried in the request message, Said the mobile exchange center VMSC number corresponding to the LAI;

a sending unit, configured to send a PRN request message carrying the VMSC number to the determined VMSC, triggering the VMSC to initiate a data recovery process, so that the VMSC obtains user data, so that the VMSC after obtaining the user data When the call request is received, a call path is established according to the user data, and the call connection is completed.

9. The circuit domain fallback agent according to claim 8, wherein the CSFB Proxy further comprises:

The configuration unit is configured to configure a mapping table between the location area identifier LAI and the visited mobile switching center VMSC number.

The circuit domain fallback agent according to claim 8 or 9, wherein the CSFB Proxy further comprises:

And a constructing unit, configured to construct a roaming number PRN request message, and encapsulate the VMSC number into the PRN request message.

The circuit domain fallback agent according to claim 10, wherein the constructing unit constructs a roaming number PRN request message, including:

The constructing unit constructs the PRN request message in accordance with a voice call message format.

The circuit domain fallback agent according to claim 11, wherein the circuit domain fallback agent further comprises:

a determining unit, configured to: when the saved VMSC number is equal to the set default value, determine that the VMSC is invalid, and when the saved VMSC number is not equal to the set default value, determine that the VMSC is valid; The saved VMSC number is not equal to the determined VMSC number, so that the CSFB Proxy constructs the PRN request message.

The circuit domain fallback agent according to claim 8, wherein, when the call is a circuit switched CS domain passive call, the CSFB Proxy further includes:

The receiving unit is further configured to receive a PRN message sent by the HLR, where the PRN message sent by the HLR carries the number of the CSFB Proxy;

a replacement unit, configured to replace the CSFB Proxy number with the VMSC number according to the saved VMSC number;

a transparent transmission unit, configured to transparently transmit a PRN message sent by the HLR to the VMSC;

The receiving unit is further configured to receive a PRN response message sent by the VMSC, where the sending unit is further configured to send the CS domain passive call response message to the mobility management entity MME, so that the MME instructs the corresponding terminal to perform CSFB operation.

14. A visit to a mobile switching center VMSC, characterized in that it comprises:

The mobile switching center VMSC according to claim 14, wherein the triggering unit triggers a data recovery process, including:

Sending a data request message to the home location register HLR; Receive user data sent by the HLR.

A system for call connection, comprising a circuit domain fallback agent CSFB Proxy and a visited mobile switching center VMSC, characterized by comprising:

The VMSC is configured to receive a PRN request message sent by the CSFB Proxy, trigger a data recovery process, obtain user data, and when the call request is received, establish a call path according to the user data, and complete the call connection.

The system according to claim 16, wherein the CSFB Proxy is further configured to: before receiving the location update request message sent by the MME:

The system according to claim 17, wherein before the CSFB Proxy constructs the PRN request message, it is further used to: