KR20130119128A - User device capable of monitoring abnormal termination of ims communication service - Google Patents

User device capable of monitoring abnormal termination of ims communication service Download PDF

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Publication number
KR20130119128A
KR20130119128A KR1020120042053A KR20120042053A KR20130119128A KR 20130119128 A KR20130119128 A KR 20130119128A KR 1020120042053 A KR1020120042053 A KR 1020120042053A KR 20120042053 A KR20120042053 A KR 20120042053A KR 20130119128 A KR20130119128 A KR 20130119128A
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KR
South Korea
Prior art keywords
ims
network
user terminal
service application
service
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Application number
KR1020120042053A
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Korean (ko)
Inventor
금기섭
Original Assignee
주식회사 케이티
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Priority to KR1020120042053A priority Critical patent/KR20130119128A/en
Publication of KR20130119128A publication Critical patent/KR20130119128A/en

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
    • H04L65/10—Architectures or entities
    • H04L65/1016—IP multimedia subsystem [IMS]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
    • H04W4/16—Communication-related supplementary services, e.g. call-transfer or call-hold
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W60/00—Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
    • H04W60/06—De-registration or detaching
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
    • H04W88/02—Terminal devices

Abstract

PURPOSE: A user terminal capable of monitoring the abnormal end of IMS (IP multimedia subsystem) communications can monitor the abnormal end of IMS communications service based on the VoLTE (voice over long term evolution) IMS service application. CONSTITUTION: A monitor (205) monitors an abnormal end of an IMS service application. A control unit (225) requests deregistration of a user terminal to an IMS network when the abnormal end of the IMS service application is detected by the monitor. The abnormal end of the IMS service application is a deletion of the IMS service application or a forced termination the IMS service application. The control unit transmits a PUID (public user ID) corresponding to a PRID (private user ID) and IMS service application of the user terminal when deregistering the user terminal in the IMS network. [Reference numerals] (205) Monitor; (210) Storage unit; (215) Input unit; (220) Communication unit; (225) Control unit

Description

User device capable of monitoring abnormal termination of an IMS communication service

The present invention relates to an IP Multimedia Subsystem (IMS) communication service technology, and more particularly, to a user equipment (UE) capable of monitoring abnormal termination of an IMS communication service, and a method of operating the user terminal.

IP Multimedia Subsystem (IMS) is a next-generation packet switched multimedia network created in consideration of a wireless terminal environment in a 3rd generation partnership project (3GPP). These IMSs support new IP-based rich content and new service capabilities by proposing a new communication business model between wireless and wired networks. In terms of services, the concept of IMS attempted to separate between service provider domain and network operator domain, different from the past development and provision of closed communication services.

In IMS network, there is a Call Session Control Function (CSCF) that handles calls. This is an infrastructure system that performs basic functions for SIP (Session Initiation Protocol) based multimedia session control, and is divided into Proxy-CSCF, Interogating-CSCF, and Serving-CSCF according to its role. The system handles subscriber registration, authentication, billing, service-specific triggering and routing to the application server, called the caller's location, compressing and decompressing SIP messages. There is a home subscriber server (HSS) that stores subscriber profile information, authentication, and location related data, and an application server that holds a service logic and provides a corresponding service.

An object of the present invention is to provide a user terminal capable of monitoring abnormal termination of an IMS communication service based on a Voice over LTE (VoLTE) IMS service application.

In order to achieve the above technical problem, a user terminal according to an embodiment of the present invention, the Voice over LTE (VoLTE) IMS service application that performs an IP Multimedia Subsystem (IMS) network access function through a long term evolution (LTE) network An installed user terminal, comprising: a monitoring unit for monitoring abnormal termination of the IMS service application; And a controller for requesting deregistration of the user terminal from the IMS network when an abnormal termination of the IMS service application is detected by the monitoring unit.

Abnormal termination of the IMS service application may be deletion of the IMS service application or forced termination of the IMS service application.

The controller may transmit a PRID (PRivate User ID) of the user terminal and a PUID corresponding to the IMS service application to the IMS network when the user terminal is deregistered from the IMS network.

The controller may control the user terminal to receive a voice service through a circuit switching network of a 3G network after requesting the IMS network to deregister the user terminal.

The user terminal according to the present invention may detect (monitor) an abnormal termination of an VoLTE IMS service client (IMS service application) in the form of an application in real time and perform IMS network registration cancellation (registration cancellation). As a result, the present invention can perform a normal procedure (call announcement reception announcement, etc.) when attempting an incoming call to the terminal by performing explicit network separation by the terminal, the network (IMS server) in the time-out processing It is possible to prevent the waste of radio resources by solving the inaccuracies in the terminal state management that may be generated by the terminal state, and enable a service requiring real-time 3G call forwarding (3G network call forwarding) according to the state of the IMS service application. .

The present invention can explicitly de-registration of an IMS network by detecting an abnormal situation such as forced termination of an IMS service application or deletion of an IMS service application mounted on the terminal. As a result, the user terminal according to the present invention does not require a re-registration cycle and guard time of the IMS network for deregistration of the IMS network and immediately receive a voice call received through the 3G network. Can be received.

In order to more fully understand the drawings used in the detailed description of the invention, a brief description of each drawing is provided.
1 is a diagram illustrating an IMS network system 400 including a user terminal 100 according to an embodiment of the present invention.
FIG. 2 is a block diagram illustrating another embodiment 200 of the user terminal shown in FIG. 1.
3 is a flow chart illustrating a method 500 of operating a user terminal according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention and the objects attained by the practice of the invention, reference should be made to the accompanying drawings, which illustrate embodiments of the invention, and to the description in the accompanying drawings.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to embodiments of the present invention with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

When the terminal (client) is normally shut down, such as when the terminal shutdown button is pressed in the 3G network (3G network) or when the battery of the terminal is naturally exhausted, the terminal detects this in advance (just before the shutdown) and disconnects the network (server). (Network-detach) can be performed. Therefore, when an incoming call is attempted to the corresponding terminal, a normal procedure such as a call reception impossible announcement due to network separation of the terminal in the 3G network may be performed.

However, in an abnormal situation such as forcibly removing the terminal battery or entering the shadow area (out of the call zone) where the network detach procedure cannot be explicitly performed, the time-out procedure may be performed in the IMS network (server). The time-out procedure refers to a procedure of forcibly separating the terminal from the network (server) when the server does not receive the location registration message from the server for a certain period of the terminal's network registration period and the guard time. do. That is, a time-out procedure (session time-out procedure) refers to processing of deregistration of a terminal by the server when the server does not receive a call response from the terminal.

On the other hand, if the network is separated by the terminal, the normal procedure (call reception announcement announcement, etc.) can be performed when an incoming call is attempted to the terminal, but the terminal (Timesout on the network (IMS server) side ( Terminating terminal) Since the state of the terminal is not known for a certain period during separation, radio resource waste may occur due to unnecessary incoming attempts. In order to solve such a problem, there may exist a method in which the terminal actively detects an abnormal situation and delivers it to a network (server) to perform an explicit network separation (deregistration) procedure.

Recently, an IMS-based communication service in the form of a downloadable app (an application that a user can install or delete (remove) on a terminal) has been provided in a terminal based on a general platform such as a smartphone. For example, the recent shift in mobile voice service technology (3G to Voice over LTE) has been rapidly driven by telecom operators around the world, and one of the forms of delivery is the VoLTE IMS client in the form of a smartphone app. To provide. VoLTE may refer to mVoIP (mobile internet phone) based on LTE / IMS.

In this type of service, a new client abnormal situation such as forced termination or deletion of an app may occur. In this case, the IMS network de-registration is not explicitly performed in the VoLTE IMS client. There may be a problem that the state of the UE is not managed during the -out processing period (the sum of the IMS re-registration period and the guard time).

In particular, there is a service that is forwarded to the 3G voice call when leaving the LTE region in an environment where the initial LTE (long term evolution) coverage is not secure enough. This service is received by VoLTE when DBDM (Dual Band Dual Mode) terminating terminal is registered in IMS network (when VoLTE app is installed and running) and when IMS registration is canceled (app is not installed) Or normal termination of the app) is forwarded to the 3G voice call. However, in an abnormal situation (abnormal termination) of the app, such as deleting the app or forcibly terminating the app, a call incapable state may occur where both VoLTE forwarding and 3G forwarding are impossible during the server time-out process.

1 is a diagram illustrating an IMS network system 400 including a user terminal 100 according to an embodiment of the present invention.

Referring to FIG. 1, the IMS network system 400 includes the user terminal 100 including the app monitoring manager 110 and the IMS network 300. The IMS network 300 receives call control from a Call Session Control Function (CSCF) server 310, an IMS core, a Home Subscriber Server (HSS) 305, and an IMS network 300. It includes an IMS Application Server (AS) (not shown) that provides a VoLTE IMS service to a user terminal 100 that is a called terminal. The IMS network 300 is linked to an internet network (IP backbone) (not shown).

CSCF 310 is a call state control function module (Call State Control Function module) responsible for the part related to call and session processing, functions as a gateway to the incoming call, call control function, SPD (Serving Profile Database) function (eg For example, the management of subscriber information received through communication with the HSS system, etc.), and an address handling function may be performed. The HSS system 305 is a database system that manages subscriber information (location information, authentication information, service information, etc.). The HSS system 305 may perform a function similar to that of a HLR (Home Location Register) and an AuC (Authentication Center) function of a mobile communication system for an IMS service. The HSS system 305 manages a registration key including a PUID (Public User ID) and a PRID (PRivate User ID) for use in authentication processing according to an IMS service. The CSCF 310 may authenticate the registration key included in the IMS service access request for the IMS AS of the user terminal 100 in cooperation with the HSS 305. The CSCF 310 may transmit subscriber information received from the HSS 305 to the IMS AS, and the IMS AS may provide an IMS service in response to the received subscriber information.

The user terminal 100 is a DBDM (Dual Band Dual Mode) called terminal capable of simultaneously providing an IMS-based VoLTE service (voice call service) and a 3G voice call service (3G circuit switching network-based call service). Can be. That is, the user terminal 100 may be a VoLTE subscriber station or a 3G mobile communication subscriber station. An LTE access network (LTE packet switching network (IP network) (not shown)) capable of interworking with the Internet network may be disposed between the user terminal 100 and the CSCF 310 of the IMS network 300. That is, the user terminal 100 may be connected to the IMS network 300 through an LTE access network. The packet switching network of LTE may include a Serving GPRS Supporting Node (SGSN) and a Gateway GPRS Supporting Node (GGSN). VoLTE is mVoIP in LTE network and transmits services such as voice and text through IMS (IP Multimedia Subsystem) architecture. IMS communication service is a platform for providing a multimedia communication service such as voice, audio, video, or data by interworking with various wired / wireless integrated networks based on an IP (Internet Protocol) network independently of wired and wireless access networks.

In the dual band dual mode (DBDM) terminal 100, a VoLTE service application for VoLTE service and a 3G service application for 3G voice call service may be installed. When the VoLTE service application is installed, the user terminal 100 receives a voice service (voice call service) through VoLTE (LTE network), and when the VoLTE service application is not installed or the VoLTE service application is normally terminated, the user terminal ( 100) is provided with a voice service through the 3G network. The DBDM terminal 100 is a terminal capable of accessing both 3G and LTE networks and includes both a 3G modem and an LTE modem.

The user terminal 100 is, for example, a mobile terminal supported by a wireless Internet service such as a smart phone, a notepad, a tablet PC, etc., and an app monitoring management unit including a monitoring unit and a control unit. 110. The app monitoring manager 110 monitors the status of the VoLTE IMS service application 105 in real time to detect abnormal termination of the application 105. In addition, the app monitoring management unit 110 is for the status of the application 115 for PSVT (Packet Switched Video Telephony Services) or Rich Communication Suite (RCS) messenger service (RCS-based text message service) The state of the application 120 may also be monitored.

When the app monitoring manager 110 detects (detects) an abnormal termination of the VoLTE IMS service application 105, the app monitoring manager 110 may perform a deregistration procedure of the user terminal 100 on the IMS network 300 on behalf of the application 105. have.

In order for the app monitoring manager 110 to register and cancel registration of the user terminal 100 in the IMS network 300, the app monitoring manager 110 performs authentication of the user terminal 100 to the IMS network 300. do. In the app monitoring management unit 110, a PRID (PRivate User ID) (corresponding to an International Mobile Subscriber Identity (IMSI) of 3G network) is used as an authentication key value. PRID is an identifier for authenticating the user terminal 100 and may be, for example, an International Mobile Subscriber Identity (IMSI) number of a subscriber identity module (SIM). That is, PRID may mean a registration key of the user terminal 10 used for registration authentication of the IMS network 300. The app monitoring manager 110 transmits the PRID to the Call Session Control Function (CSCF) 310 of the IMS network to perform authentication. The CSCF 310 may provide authentication completion information of the user terminal 100 to the app monitoring manager 110 by referring to the HSS 305 (query the HSS 305).

When the authentication is successful, the app monitoring manager 110 transmits a public user ID (PUID), which is a service registration key value, to the call session control function (CSCF) 310 of the IMS network. The PUID is an identifier for incoming routing of the user terminal 100 and may be, for example, a user telephone number such as a mobile subscriber ISDN number (MSISDN) of a 3G network. That is, the PUID may mean a registration key for identifying a user (user terminal) for IMS communication service or session control. The CSCF 310 may cancel the VoLTE IMS service registration of the user terminal 100 with respect to the HSS 305.

In detail, the app monitoring manager 110 may cancel the service registration of the user terminal 100 in the IMS network 300 when an abnormal termination of an app such as deletion or forced termination of the VoLTE IMS service application 105 occurs. For example, a PRID of “1” and a PUID of “a” may be delivered to the CSCF 310 of the network 300.

In order for the app monitoring manager 110 to perform a service registration cancellation procedure on behalf of an abnormally terminated application, an app management table 125 may be installed (included) in the user terminal 100. In another embodiment of the present invention, the app management table 125 may be included in the app monitoring manager 110.

The app management table 125 manages the PRID (eg, 1) of the user terminal 100 and the PUID for each service application (eg, a, b, and c). In the app management table 125, a service application PID (Process ID) mapped to a PUID for each service application may be disposed (created). The service application PID (Process ID) is generated when the service application 105, 115, or 125 is started or terminated.

For example, when the app monitoring manager 110 detects (detects) an abnormal termination of the VoLTE IMS service application 105, the PUID (eg, a) corresponding to the corresponding PID (eg, 1) and the user terminal are detected. PRID (for example, 1) of 100 is included in the de-registration message and transmitted to CSCF 310 of IMS network 300. The CSCF 310 may perform the IMS service deregistration procedure of the user terminal 100 by deleting the corresponding PRID and the PUID from the HSS 305 using the transferred PUID and the PRID. When the CSCF 310 completes the execution of the IMS service deregistration procedure, the session between the user terminal 100 and the IMS network 300 ends.

As described above, in the present invention, when the IMS service application 105 in the form of a downloadable app that is frequently installed or deleted by the user and forcedly terminates is deleted or forcedly terminated, the user terminal 100 according to the present invention. ) May perform a normal de-registration procedure on the IMS network 300.

FIG. 2 is a block diagram illustrating another embodiment 200 of the user terminal shown in FIG. 1.

Referring to FIG. 2, the user terminal 200 includes a monitoring unit 205, a storage unit 210, an input unit 215, a communication unit 220, and a control unit 225. The monitor 205, the storage 210, and the controller 225 may correspond to the app monitoring manager 110 of FIG. 1.

The storage unit 210 performs a Voice over LTE (VoLTE) IMS service application (105 of FIG. 1) that performs IP Multimedia Subsystem (IMS) network access through a long term evolution (LTE) network, and a packet switched video telephony service (PSVT). 1) or an application (120 of FIG. 1) for an RCS messenger service (RCS based text message service). In addition, the storage unit 210 may store an app management table (125 in FIG. 1), a 3G service application for 3G voice call service, and a registration key including a PUID and a PRID.

The monitoring unit 205 monitors abnormal termination of the IMS service application, the PSVT application, or the RCS text message service application.

The control unit 225 detects (detects) abnormal termination of the IMS service application by the monitoring unit 205 (when an abnormal termination signal of the application is transmitted from the monitoring unit 205 to the control unit 225). The request for 300 (deregistration of location registration) of the user terminal 200 is requested (transmitted) through the communication unit 220. In another embodiment of the present invention, the controller 225 may include a monitor 205 and a storage 210. Abnormal termination of the IMS service application may be deletion of the IMS service application by the user of the user terminal 200 or forced termination of the IMS service application.

When the controller 225 deregisters the user terminal 200 from the IMS network, the control unit 225 sends a PRID (PRivate User ID) of the user terminal 200 and a PUID corresponding to the IMS service application to the IMS network. To pass.

The controller 225 requests the IMS network to deregister the service of the user terminal 200 (or receives a message (signal) indicating that deregistration of the user terminal 200 is completed from the IMS network through the communication unit 220). When the user terminal 200 is controlled to receive (receive) voice service (voice data call) through a circuit switching network (circuit switching network) of the 3G network (3 generation network). The circuit switched network may include a switch which is a call processing system.

The controller 225 performs a function of a central processing unit (CPU) and controls the overall operations of components such as the monitor 205 and the storage 210 included in the user terminal 100.

The input unit 215 includes a button for installing, deleting, or forcibly terminating the IMS service application, the PSVT application, or the RCS text message service application.

3 is a flow chart illustrating a method 500 of operating a user terminal according to an embodiment of the present invention. The operation method 500 of the user terminal may be applied to the user terminal 100 or 200 illustrated in FIG. 1 or 2.

Referring to FIG. 3, in an IMS communication step 505, a user terminal runs a VoLTE IMS service application to perform an IMS communication service through an LTE network. In this case, the user terminal may use PRID and PUID for IMS communication.

According to the monitoring step 510, the monitoring unit of the user terminal monitors whether the app abnormally terminated, such as deleting or forcibly terminating the IMS service application. When the app is not abnormally terminated, the operating method 500 of the user terminal performs the IMS communication step 505, and when the app is abnormally terminated, the method 500 of the user terminal proceeds to the deregistration step 515. .

According to the deregistration step 515, when an abnormal termination of the IMS service application is detected by the monitoring unit (when an abnormal termination signal of the application is transmitted from the monitoring unit to the control unit), the control unit of the user terminal is connected to the IMS network. Request deregistration (registration cancellation) of the user terminal. In this case, the user terminal may use PRID and PUID.

According to the call forwarding step 520, the controller of the user terminal requests the IMS network to deregister the service of the user terminal and then controls the user terminal to receive a voice service through the 3G network.

The components or " units " or blocks or modules used in the present embodiment may be implemented in software such as a task, a class, a subroutine, a process, an object, an execution thread, , A field programmable gate array (FPGA), or an application-specific integrated circuit (ASIC), or a combination of the above software and hardware. The components or parts may be included in a computer-readable storage medium, or a part of the components may be dispersed in a plurality of computers.

As described above, the embodiments have been disclosed in the drawings and specification. Although specific terms are used herein, they are used for the purpose of describing the present invention only and are not used to limit the scope of the present invention described in the claims or the claims. It is therefore to be understood by those skilled in the art that various modifications and equivalent embodiments are possible in light of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

110: app monitoring management
125: App management table
205: watchdog
210:
225:

Claims (4)

In a user terminal installed with a Voice over LTE (VoLTE) IMS service application that performs an IP Multimedia Subsystem (IMS) network access function through a long term evolution (LTE) network,
A monitoring unit for monitoring abnormal termination of the IMS service application; And
And a controller for requesting release of the user terminal from the IMS network when an abnormal termination of the IMS service application is detected by the monitoring unit. The method of claim 1,
The abnormal termination of the IMS service application is deletion of the IMS service application or forced termination of the IMS service application. The method of claim 1,
The control unit transmits a PRID (PRivate User ID) of the user terminal and a PUID (Public User ID) corresponding to the IMS service application to the IMS network when the user terminal is deregistered from the IMS network. . The method of claim 1,
The controller controls the user terminal to receive a voice service through a circuit switching network of a 3G network after requesting the IMS network to deregister the user terminal.
KR1020120042053A 2012-04-23 2012-04-23 User device capable of monitoring abnormal termination of ims communication service KR20130119128A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9998959B2 (en) 2014-03-25 2018-06-12 Samsung Electronics Co., Ltd Electronic device and method for providing call services for the same
CN115811570A (en) * 2023-01-27 2023-03-17 荣耀终端有限公司 IMS call voice quality testing method and system

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9998959B2 (en) 2014-03-25 2018-06-12 Samsung Electronics Co., Ltd Electronic device and method for providing call services for the same
CN115811570A (en) * 2023-01-27 2023-03-17 荣耀终端有限公司 IMS call voice quality testing method and system
CN115811570B (en) * 2023-01-27 2023-08-18 荣耀终端有限公司 IMS call voice quality testing method and system

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