WO2015174806A1

WO2015174806A1 - Method and device for improving voice call service quality

Info

Publication number: WO2015174806A1
Application number: PCT/KR2015/004975
Authority: WO
Inventors: 정상수; 조성연
Original assignee: 삼성전자 주식회사
Priority date: 2014-05-16
Filing date: 2015-05-18
Publication date: 2015-11-19

Abstract

The present disclosure relates to a communication technique for convergence of an IoT technology and a 5G communication system for supporting higher data transmission rates after a 4G system, and a system therefor. The present disclosure can be applied to an intelligent service on the basis of a 5G communication technology and an IoT-related technology (e.g., a smart home, a smart building, a smart city, a smart car or a connected car, healthcare, digital education, retail business, security, and a safety-related service). A method for transmitting and receiving a signal by a terminal in a mobile communication system according to an embodiment of the present specification comprises the steps of: transmitting, to a server, a first message including at least one of an identifier of a terminal and location information of the terminal; receiving, from the server, a second message including a providable service list determined according to the first message; and receiving an access token for using at least one of services included in the service list. Further, according to an embodiment of the present specification, various services may be effectively provided to a user terminal.

Description

Method and device for improving voice call quality of service

Embodiments of the present disclosure relate to connection control in a mobile communication network, and more particularly, to a method and apparatus for improving the quality of voice service by reducing the time required to set up a voice call in a mobile communication system.

In general, mobile communication systems have been developed to provide voice services while guaranteeing user activity. However, mobile communication systems are gradually expanding not only voice but also data services, and now they have developed to the extent that they can provide high-speed data services. However, in the mobile communication system in which a service is currently provided, a shortage of resources and users demand faster services, and thus, a more advanced mobile communication system is required.

In response to these demands, one of the systems being developed as a next-generation mobile communication system, a specification work for Long Term Evolution (LTE) is underway in the 3GPP (The 3rd Generation Partnership Project). LTE is a technology that implements high-speed packet-based communication with a transmission rate of up to 100 Mbps. To this end, various methods are discussed. For example, the network structure can be simplified to reduce the number of nodes located on the communication path, or the wireless protocols can be as close to the wireless channel as possible.

In order to meet the increasing demand for wireless data traffic since the commercialization of 4G communication systems, efforts are being made to develop improved 5G communication systems or pre-5G communication systems. For this reason, a 5G communication system or a pre-5G communication system is called a system after a 4G network (Beyond 4G Network) or a system after an LTE system (Post LTE). In order to achieve high data rates, 5G communication systems are being considered for implementation in the ultra-high frequency (mmWave) band (eg, such as the 60 Gigabit (60 GHz) band). In order to mitigate the path loss of radio waves in the ultra-high frequency band and increase the propagation distance of radio waves, beamforming, massive array multiple input / output (FD-MIMO), and FD-MIMO are used in 5G communication systems. Array antenna, analog beam-forming, and large scale antenna techniques are discussed. In addition, in order to improve the network of the system, 5G communication systems have advanced small cells, advanced small cells, cloud radio access network (cloud RAN), ultra-dense network (ultra-dense network) , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation The development of such technology is being done. In addition, in 5G systems, Hybrid FSK and QAM Modulation (FQAM) and sliding window superposition coding (SWSC), Advanced Coding Modulation (ACM), and FBMC (Filter Bank Multi Carrier) and NOMA are advanced access technologies. (non orthogonal multiple access), and sparse code multiple access (SCMA) are being developed.

Meanwhile, the Internet is evolving from a human-centered connection network in which humans create and consume information, and an Internet of Things (IoT) network that exchanges and processes information between distributed components such as things. The Internet of Everything (IoE) technology, which combines big data processing technology through connection with cloud servers and the like, is emerging. In order to implement the IoT, technical elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, a sensor network for connection between things, a machine to machine , M2M), Machine Type Communication (MTC), etc. are being studied. In an IoT environment, intelligent Internet technology (IT) services can be provided that collect and analyze data generated from connected objects to create new value in human life. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliances, advanced medical services, etc. through convergence and complex of existing information technology (IT) technology and various industries. It can be applied to.

Accordingly, various attempts have been made to apply the 5G communication system to the IoT network. For example, technologies such as sensor network, machine to machine (M2M), machine type communication (MTC), and the like, are implemented by techniques such as beamforming, MIMO, and array antennas. It is. Application of cloud radio access network (cloud RAN) as the big data processing technology described above may be an example of convergence of 5G technology and IoT technology.

1 is a diagram illustrating a structure of a general LTE mobile communication system.

Referring to FIG. 1, as illustrated, a radio access network of an LTE mobile communication system includes a next-generation base station (evolved Node B, EUTRAN, hereinafter referred to as ENB or Node B) 110, a mobility management entity 120, and an MME 120. It may include an S-GW (Serving Gateway, 130).

The user equipment (hereinafter referred to as UE) 100 is connected to the external network through the ENB 110 and the S-GW 130 and the P-GW 140 (PDN Gateway; Packet Data Network Gateway). .

ENB (base station) 110 is a Radio Access Network (RAN) node, which is a Radio Network Controller (RNC) of a Universal Terrestrial Radio Access Network (UTRAN) system and a Base Station Conroller (BSC) of a GSM EDGE Radio Access Network (GERAN) system. Corresponds to. The ENB 110 is connected to the UE 100 through a radio channel and plays a role similar to that of the existing RNC / BSC. The ENB can use multiple cells at the same time.

In LTE, all user traffic, including real-time services such as Voice over IP (VoIP) over the Internet protocol, is serviced through a shared channel, which requires a device that collects scheduling information of UEs and schedules them. In charge.

The MME 120 is a device that is in charge of various control functions. One MME may be connected to a plurality of base stations.

The S-GW 130 is a device for providing a data bearer, and generates or removes a data bearer under the control of the MME 120.

Meanwhile, the core network of the LTE mobile communication system may further include nodes (not shown) such as application functions, PCRF, and P-GW, in addition to the MME 120 and the S-GW 130.

An application function (AF) is a device that exchanges information related to an application at the user and application level.

Policy Charging and Rules Function (PCRF) is a device that controls the policies related to the quality of service (QoS) of users, and the policy and charging control (PCC) rules corresponding to the policy are P- Applies to GW. The PCRF (Policy Charging and Rules Function) is an entity that collectively controls QoS and charging for traffic.

On the other hand, the UP generally refers to the UE 100 and RAN node 110 to which user data is transmitted and received, the S-GW 130 at the RAN node 110, and the P-GW (at the S-GW 130). 160 refers to the path connecting. However, a portion of the path using a radio channel with a severe resource limitation is a path between the UE 100 and the RAN node 110.

Meanwhile, a unit to which QoS can be applied in a wireless communication system such as LTE is an Evolved Packet System (EPS) bearer. One EPS bearer is used to transmit IP flows having the same QoS requirements. The EPS bearer may be assigned a parameter related to QoS, which includes a QoS Class Identifier (QCI) and Allocation and Retention Priority (ARP). The QCI is a parameter that defines the QoS priority as an integer value, and the ARP is a parameter that determines whether to allow or reject the creation of a new EPS bearer.

The EPS bearer corresponds to a Packet Data Protocol (PDP) context of a General Packet Radio Service (GPRS) system. One EPS bearer belongs to a PDN connection, and the PDN connection may have an access point name (APN) as an attribute. If a PDN connection is created for an IP Multimedia Subsystem (IMS) service such as Voice over LTE (VoLTE), the PDN connection should be created using a well-known IMS APN.

On the other hand, in the LTE network, CSFB (CS) using IMS-based Voice over LTE (VoLTE) technology as a packet switched method to support voice calls or recycling a CS (circuit switched) method of 2G / 3G systems fall back) technology. VoLTE in LTE network is a term that can be used in the same concept as Voice over IMS (VoIMS).

In such a wireless communication system, in particular, when an incoming or outgoing voice call is generated while a terminal uses an LTE network in an LTE system, a CSFB (Circuit Switched Fall Back) process for switching to a CS (Circuit Switched) network is performed. . In this case, since a separate authentication procedure for the terminal is required, there may be a delay in providing a voice service. In general, a 2G / 3G system is a CS network capable of providing CS services, and an entity in charge of control related to CS services is called an MSC (or VLR). CSFB, which provides a switching function for CS service in LTE, is made using an SGs interface between an MSC / VLR and an MME.

As described above, when performing CSFB to provide a voice call, a delay due to acknowledgment may occur. Therefore, a method and apparatus for solving such a problem are required.

Embodiments of the present disclosure have been made to solve the above problems, and an object thereof is to provide a method and apparatus for shortening a voice call setup time in a mobile communication system.

Specifically, an embodiment of the present disclosure is to provide a method and apparatus for shortening the service delay caused by the authentication or security information exchange process required when the terminal moves to another service while receiving a specific service. do.

In addition, an embodiment of the present disclosure, a method and apparatus for shortening a service delay by performing radio resource setting for a new service in parallel with a switching process of a terminal when the terminal moves to another service while receiving a specific service. To provide that purpose.

In order to achieve the above object, a signal transmission and reception method in a terminal of a mobile communication system according to an embodiment of the present disclosure includes the steps of transmitting a first message including at least one of the identifier of the terminal and the location information of the terminal; Receiving a second message from the server, the second message including a list of available services determined according to the first message; And receiving an access token for using at least one of the services included in the service list.

In a server of a mobile communication system according to another embodiment of the present disclosure, the method for transmitting and receiving a signal includes: receiving a first message including at least one of an identifier of a terminal and location information of the terminal from the terminal; Transmitting a second message to the terminal, the second message including a list of available services determined according to the first message; Receiving a third message from the terminal, the third message including information for selecting at least one service from the service list; And generating information for using the selected service based on the third message.

Terminal of a mobile communication system according to another embodiment of the present disclosure includes a transceiver for transmitting and receiving a signal; And a first message including at least one of an identifier of the terminal and location information of the terminal to a server, receiving a second message including a list of available services determined according to the first message from the server, and receiving the service. And a control unit controlling the transceiver to receive an access token for using at least one of the services included in the list.

Server of a mobile communication system according to another embodiment of the present disclosure includes a transceiver for transmitting and receiving a signal; And a first message including at least one of an identifier of the terminal and location information of the terminal from the terminal, and transmitting a second message to the terminal, the second message including a list of available services determined according to the first message. And a controller configured to control the transceiver to receive a third message including information for selecting at least one service from a service list from the terminal, and to generate information for using the selected service based on the third message. do.

According to an exemplary embodiment of the present disclosure, a method and apparatus for shortening a time for setting up a voice call in a mobile communication system and reducing an information exchange process when moving to another service while receiving a specific service may be provided.

In addition, according to an embodiment of the present disclosure it is possible to provide efficient communication by exchanging SRVCC-related information in the mobile communication system.

In addition, according to an embodiment of the present disclosure it can effectively provide a variety of services to the user terminal.

2 is a view showing the operation of the terminal and the network to shorten the call setup time during the CSFB process.

3 is a diagram illustrating a CSFB process in a network according to an embodiment.

4 is a diagram illustrating a process of checking whether an eCSFB function is supported by a terminal and a network in a registration process.

5 is a diagram for notifying the base station that the base station supports the eCSFB in the S1 setup step.

FIG. 6 is a diagram in which an old MME delivers SRVCC related information when an SRVCC supporting terminal performs Attach / TAU in which an MME is changed.

FIG. 7 is a diagram in which an SRVCC related terminal delivers SRVCC related information when an SRVCC supporting terminal performs Attach / TAU with an MME changed.

8 is a diagram in which the HSS delivers SRVCC related information when an SRVCC supporting terminal performs Attach / TAU in which an MME is changed.

9 is a diagram illustrating a terminal according to an embodiment.

10 is a diagram illustrating a base station according to an embodiment.

11 is a diagram illustrating a mobility management entity according to an embodiment.

12 is a diagram illustrating a home subscriber server (HSS) according to an embodiment.

FIG. 13 is a diagram illustrating an operation of performing a cell (or RAT) change procedure before setting DRB and AS security during a CSFB process according to one embodiment of the present specification.

14 is a diagram illustrating an operation of a base station in a CSFB process according to an embodiment of the present disclosure.

FIG. 15 is a diagram illustrating a method for reducing a voice call setup time of a user terminal according to one embodiment of the present specification.

16 is a diagram illustrating a sponsored data service concept and a service flow according to an embodiment.

17 is a diagram more specifically illustrating an information exchange process for starting an ODC service according to an embodiment.

FIG. 18 is a diagram illustrating an information exchange process for initiating an ODC service in another embodiment.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing the embodiments, descriptions of technical contents which are well known in the technical field to which the present invention belongs and are not directly related to the present invention will be omitted. This is to more clearly communicate without obscure the subject matter of the present invention by omitting unnecessary description.

For the same reason, in the accompanying drawings, some components are exaggerated, omitted or schematically illustrated. In addition, the size of each component does not fully reflect the actual size. The same or corresponding components in each drawing are given the same reference numerals.

Advantages and features of the present invention, and methods for achieving them will be apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms, and only the embodiments of the present invention make the disclosure of the present invention complete and the general knowledge in the technical field to which the present invention belongs. It is provided to fully convey the scope of the invention to those skilled in the art, and the invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

At this point, it will be understood that each block of the flowchart illustrations and combinations of flowchart illustrations may be performed by computer program instructions. Since these computer program instructions may be mounted on a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, those instructions executed through the processor of the computer or other programmable data processing equipment may be described in flow chart block (s). It creates a means to perform the functions. These computer program instructions may be stored in a computer usable or computer readable memory that can be directed to a computer or other programmable data processing equipment to implement functionality in a particular manner, and thus the computer usable or computer readable memory. It is also possible for the instructions stored in to produce an article of manufacture containing instruction means for performing the functions described in the flowchart block (s). Computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operating steps may be performed on the computer or other programmable data processing equipment to create a computer-implemented process to create a computer or other programmable data. Instructions for performing the processing equipment may also provide steps for performing the functions described in the flowchart block (s).

In addition, each block may represent a portion of a module, segment, or code that includes one or more executable instructions for executing a specified logical function (s). It should also be noted that in some alternative implementations, the functions noted in the blocks may occur out of order. For example, the two blocks shown in succession may in fact be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending on the corresponding function.

In this case, the term '~ part' used in the present embodiment refers to software or a hardware component such as an FPGA or an ASIC, and '~ part' performs certain roles. However, '~' is not meant to be limited to software or hardware. '~ Portion' may be configured to be in an addressable storage medium or may be configured to play one or more processors. Thus, as an example, '~' means components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, procedures, and the like. Subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within the components and the 'parts' may be combined into a smaller number of components and the 'parts' or further separated into additional components and the 'parts'. In addition, the components and '~' may be implemented to play one or more CPUs in the device or secure multimedia card.

In addition, it should be noted that in describing the embodiments, like elements are denoted by like reference numerals as much as possible. In addition, detailed descriptions of well-known functions and configurations that may blur the gist of the present invention will be omitted.

In addition, the embodiments of the present specification will be described in detail, while the OFDM-based wireless communication system, in particular, the 3GPP EUTRA standard will be the main target, but the gist of the present specification also applies to other communication systems having a similar technical background and channel form. Applicable in a few variations without departing from the scope of the invention significantly, this will be possible in the judgment of those skilled in the art.

In addition, in describing the embodiments of the present disclosure in detail, the user terminal will use the LTE, the main switching target CSFB (Circuit Switched Fall Back) process for switching to the CS network for voice services, but the subject matter of the present disclosure Is to shorten the process of exchanging authentication / security information required when switching from one system to another for a particular service, which does not significantly exceed the scope of the present invention in other communication systems or services having a similar technical background. Applicable in a few variations on the scope, which will be possible in the judgment of those skilled in the art.

In addition, in the case of an identifier (eCSFB_indicator) indicating that an enhanced CSFB transmitted or received by at least one of the network entities or the terminal, that is, the quick call setup function during the CSFB process is applied throughout the embodiment, the CSFB indicated in the embodiment of the present specification. It may be an identifier indicating whether or not to support, and more specifically, may be one or more of an identifier indicating whether or not CS only or CSFB handover with CS only. In addition, although the name of the identifier may be applied differently according to some variations of the embodiment, it may correspond to an embodiment of the present disclosure in that it includes information indicating whether to support the CSFB described in the embodiment.

Meanwhile, in the present specification and drawings, the LTE network may be used in the same sense as the E-UTRAN, and the CS network may be UTRAN, GERAN, CDMA2000, or a similar network capable of supporting CS services, collectively referred to as a legacy network. Can be called

In addition, in the present specification and the drawings, being in one network may cover both cases of being connected to one network or camping in an idle state. In addition, the term base station may correspond to an eNB in the case of an E-UTRAN.

In addition, in the present specification and drawings, a CS security key may broadly refer to a CS security context as a whole, which means CK '(or CK), IK' (or IK), and KSI. It may be information including at least one of a key set identifier, an integrity protection algorithm, a start value, and a ciphering algorithm. In other words, the CS security key may be referred to as CS security key related information according to one embodiment of the present specification, may mean the CS security key itself, or to generate the CS security key. It may also include at least one parameter required.

In addition, in the embodiments and the drawings of the present specification, the HSS may be an entity identical or physically or logically collocated with the HRL.

If the user terminal is present in the E-UTRAN, but the incoming or outgoing voice call occurs, the CSFB process can be started. The user terminal transmits a request for CSFB to the MME through an extended service request message. Then, the MME receiving the message determines whether the CSFB is possible, and if possible, indicates to the eNB that the CSFB is required for the Initial Context Setup Request message or the UE Context Modification Request message. Deliver with a reason.

Receiving this, the eNB transmits a handover command (Handover command or RRC connection release) for CSFB to the user terminal.

Upon receiving this, the user terminal attempts to connect by switching to a legacy network supporting the CS service.

The CSFB process is intended to conceptually describe the operation of 3GPP TS 23.272, and a more detailed process may be based on the 3GPP TS 23.272. In addition, in the description of the embodiments of the present disclosure, for the sake of simplicity, the MME will be described as an example of directly exchanging information with the MSC. However, the embodiments of the present specification may be applied to a case in which the MSC server and the MSC are separated. In this case, the MSC server performs an operation using the information received from the MME, but performs an MSC-MSC handover process and delivers the information to the MSC. In addition, in the embodiment of the present specification, the CS key generated by the MME or the UE for use during the CSFB handover process will be referred to as CK _CSFB or IK _CSFB , but this is the CS key that was originally created and used during the SRVCC handover process. _May be replaced by using _SRVCC , IK _SRVCC .

Referring to FIG. 2, a user equipment (UE) 201, a base station (eNodeB, eNB) 202, a radio network controller (RNC) / base station controller (203), At least one of a mobility management entity (MME) 204 or a mobile switching center (MSC) 205 may transmit and receive a signal. In an embodiment, the RNC / BSC 203 may be referred to as a 2G / 3G base station.

In step 210, the terminal 201 may camp on the LTE network, and the CSFB process may be triggered by the terminal or the network. In an embodiment, when the CSFB process is triggered (ie, when the user requests a mobile originating call or receives a paging for the mobile terminating call from the network), the user terminal 201 may start the MME 204 to start the CSFB process. Extended Service Request message can be sent to. The MME 204 recognizes the need for the CSFB according to the Extended Service Request message received from the user terminal 201, and starts the operation accordingly.

In step 215, the MME 204 may send an S1_AP message for the CSFB to the base station node 202. The S1_AP message may include an identifier (eCSFB_indicator) indicating that an improved CSFB, i.e., a quick call setup function, is applied during the CSFB process. In addition, applying the quick call setup function during the CSFB process in the present process and the subsequent process may indicate that the PS bearer information is not exchanged or set during the CSFB process (CS_only_Indicator). The improved CSFB may be a term for describing an embodiment of the present disclosure, and the S1_AP message may include an identifier indicating that the CSFB is applied according to an embodiment of the present disclosure.

In the above process, the S1 AP message may be one of an Initial Context Setup Request (when the terminal was in idle mode) or a UE context modification request (when the terminal was in connected mode), and the quick call during the improved CSFB, that is, the CSFB process. An identifier (eCSFB_indicator) indicating that the setting function is applied may be expressed as a value of the CS Fallback Indicator of the message or may be delivered as a separate indicator.

When the identifier indicating that the improved CSFB is applicable is transmitted only after confirming whether the corresponding function of the user terminal 201, the base station 202, and the core network is supported, or when it is permitted in the user's subscription information, It can also be delivered to one. In addition, the S1_AP message may include information indicating that handover for the PS bearer is unnecessary.

The base station 202 receiving the S1 AP message starts the CSFB process, and if it is possible to apply the enhanced CSFB, that is, the quick call setup function can be applied during the CSFB process. This may be applied only when the S1 AP message received from the MME 204 includes whether to apply the corresponding function. The base station 202 may perform the measurement process with the terminal 201 if necessary, and may select a 2G / 3G (GERAN / UTRAN or 1xRTT) cell to be the target of the CSFB.

The base station 202 may deliver information to the target cell (base station) to be the CSFB terminal through the source to target transparent container, when the improved CSFB function is applied in the embodiment, the information related to the CS Fallback Indicator of the container It can be expressed as a value or inserted and delivered as a separate indicator.

In step 220, the base station 202 indicates that the source to target transparent container, the target base station (RNC or BSC 203) ID, or the improved CSFB function is applied to the message indicating that the CSFB process should be performed. Deliver one or more of the pieces of information it represents In this case, the improved CSFB, that is, the indicator indicating that the quick call setup function is applied during the CSFB process may be expressed as one value of the CS Fallback Indicator of the message or may be delivered as a separate indicator. The message transmitted by the base station 202 to the MME 204 during the process may be a Handover Required message or a CSFB Required message.

On the other hand, if the base station 202 determined to proceed with the CSFB process for the user terminal performs the operation of releasing the RRC connection (release) for the user terminal according to the original CSFB operation, the base station 202 if the improved CSFB If the process is applied, the RRC connection to the user terminal 201 is not released until the base station 202 receives a separate response message from the MME 204 as shown in step 225 and starts a timer corresponding to the CSFB. Can be. If the base station 202 does not receive a message for enhanced CSFB operation from the MME 204 until the timer expires, or the message includes information indicating that the MME 204 cannot perform the enhanced CSFB operation. If the base station 202 is delivered, the base station 202 may perform an existing CSFB operation (redirection information or NACC for moving to a 2G / 3G cell while releasing an RRC connection) with respect to the user terminal 201. This process may be performed in parallel with other processes performed after the base station 202 receives information indicating that the CSFB is needed from the MME 204.

In step 230, the MME 204 may generate and forward the information to the MSC 205 for the improved CSFB.

In an embodiment, when the improved CSFB is to be used, the MME 204 generates CK and IK, which are security keys to be used in the CS network, using K _ASME and, if necessary, NAS counts among EPS security contexts stored therein. In the embodiment, these CS keys are used for the CSFB. In the embodiment, the CS keys may be referred to as CK _CSFB and IK _CSFB . It also assigns the value of eKSI to KSI. The MME 204 generates and sends an SGs AP message to the MSC 205. The SGs AP message includes an identifier of the user terminal 201, a service identifier, CS keys generated by the MME, and a KSI or a base station 202. At least one of the received Source to target transparent container may be included. In this case, the improved CSFB, that is, the indicator indicating that the quick call setup function is applied during the CSFB process may be expressed as a value of the service indicator of the message or may be delivered as a separate indicator. In addition, the message transmitted to the MSC 205 by the MME 204 may be an SGs AP Service Request, an SGs AP CS Handover Request, or an SGs AP CSFB Request message.

In step 235, the MSC 205 uses the received CS key (CK _CSFB , IK _CSFB ) and KSI for the CSFB process, that is, the MSC 205 uses the received CK _CSFB and IK _CSFB as CK and IK. However, if there is already a key (CK, IK, etc.) and KSI stored for the user terminal 201, it can be updated with the Key and KSI received from the MME (204). If the MSC server and the target MSC are separated, the two separated entities may additionally perform the MSC-MSC HO process. If the target cell is GERAN (2G), the MSC 205 may generate and use the GSM CS cipher key Kc or Kc ₁₂₈ from the CS key (CK _CSFB , IK _CSFB or CK, IK).

In an embodiment, the MSC 205 may perform resource allocation by exchanging a Handover Request / Ack message with a 2G / 3G base station.

More specifically, in step 240, the MSC 205 may transmit a Handover Request message to the RNC / BSC 203. At this time, the MSC 205 transfers the source to target transparent container received from the MME 204 to the target 2G / 3G base station 203 using a Handover Request message, which includes an improved CSFB, that is, a fast call during the CSFB process. An indicator indicating that the setting function is applied may be included.

In step 245, the 2G / 3G base station 203 may allocate resources for the CS call.

In step 250, the 2G / 3G base station 203 may include information including resource usage and cell access information of 2G / 3G in a target to source transparent container, insert the container into a Handover Ack message, and deliver the information to the MSC 205. have. The Handover Ack message or container may include information indicating that an improved CSFB function is applied.

In step 255, the MSC 205 may send an SGs AP response message to the MME 204. The SGs AP response message may include a target to source transparent container received from the 2G / 3G base station 203. In addition, the SGs AP response message or container may include information indicating that an improved CSFB function is applied. In an embodiment, the SGs AP message may be an SGs AP Service Response, an SGs AP CS Handover Response, or an SGs AP CSFB Response.

In step 260, the MME 204 may transmit an S1 AP message instructing the base station 202 to switch the terminal 201 to a 2G or 3G cell. In an embodiment, the S1 AP message may include a target to source transparent container received from the MSC 205. In addition, the S1 AP message or container may include information indicating that an improved CSFB function is applied. In an embodiment, the S1 AP message may be an S1 AP Handover Command message.

In step 265, the base station 202 may transmit an RRC message instructing the terminal 201 to switch to a 2G or 3G cell. The RRC message may include at least one of an identifier indicating that it is a target to source transparent container or a CSFB received from the MSC 205. In addition, the identifier indicating that the CSFB may be eCSFB or CS_only_indicator. In this case, the improved CSFB, that is, indicating that the quick call setup function is applied during the CSFB process may be expressed as a value of an identifier indicating that the CSFB is included in the RRC message or may be delivered as a separate indicator. In addition, the RRC message may include an ID (Target ID) of the target cell to which the terminal accesses. In an embodiment, the RRC message may be an RRC HO from E-UTRA Command message. In addition, the user terminal 201 may proceed with the CSFB process without error processing even if the received RRC message does not have a PS resource set in the 2G / 3G network during the handover process.

The terminal 201 attempts to access 2G / 3G according to the command message received from the base station 202.

In step 270, if the user terminal 201 receives information indicating that the current process is an improved CSFB, the user terminal 201 undergoes a process of generating a CS key and KSI. In an embodiment, the process of generating the CS key and the KSI may be performed similarly to the process performed by the MME 204. That is, when the user terminal 201 needs to use the improved CSFB, the user terminal 201 may generate CK and IK, which are security keys to be used in the CS network, using K _ASME and, if necessary, NAS count in the EPS security context stored therein. In the embodiment, CS keys are used for _CSFB and may be _{referred to} as CK _CSFB and IK _CSFB . In addition, the terminal 201 may assign a value of eKSI to KSI. If the target cell to be accessed by the user terminal 201 is 2G (GERAN), the user terminal 201 generates and uses a GSM CS cipher key Kc or Kc ₁₂₈ from a CS key (CK _CSFB , IK _CSFB or CK, IK). Can be. The user terminal 201 then uses the generated CS key and KSI when generating and transmitting a message for the CS service (ie, integrity protection or ciphering) or receiving a message (ie, integrity check or decryption). That is, the user terminal 201 uses the CS key (CK _CSFB , IK _CSFB ) and KSI received for the CSFB process thereafter, which uses the CK _CSFB and IK _CSFB received by the terminal 201 as CK and IK. If there is a key (CK, IK, etc.) and KSI already stored by the user terminal 201, it is updated with the key and KSI received from the MME 204.

In operation 275, the user terminal 201 may transmit at least one of a Location Upate message or a CM service Request message to the 2G / 3G base station 203 or the MSC 205. In an embodiment, the user terminal 201 may include the KSI used by the user terminal in the message sent to the 2G / 3G base station 203 or the MSC 205. In an embodiment, the MSC 205 may communicate with the security information generated in operation 270.

In step 280, the 2G / 3G base station 203 or the MSC 205 that has received the message from the user terminal 201 may receive the KSI included in the received message, and may perform integrity check or decryption on the received message. The CS key and KSI described in step 235 may be used.

Thereafter, the remaining call establishment process may be performed in step 285.

On the other hand, the MSC 205 may inform the MME 204 through the SGs AP message when the CS call setup is completed, the MME 204 receives the SME performs a process for releasing the S1 connection with the base station 202 can do.

On the other hand, if the PS bearers are not HO during the CSFB process in the preceding process, information about the PS bearer need not be included, the PS bearer may be suspend processing in the LTE network.

Referring to FIG. 3, a user equipment (UE) 310, a base station (eNodeB, eNB) 302, a radio network controller (RNC) / base station controller 303, At least one of a mobility management entity (MME) 304 or a mobile switching center (MSC) 305 may transmit and receive a signal. In an embodiment, the RNC / BSC 303 may be referred to as a 2G / 3G base station.

In step 310, the terminal 301 may camp on the LTE network, and the CSFB may be triggered by the network. In an embodiment, when the CSFB process is triggered (that is, when the user requests a mobile originating call or receives a paging for the mobile terminating call from the network), the user terminal 301 may use the MME 304 to start the CSFB process. Extended Service Request message can be sent to. The MME 304 recognizes the need for the CSFB according to the Extended Service Request message received from the user terminal 201 and starts the operation accordingly.

In step 315, the MME 304 may send an S1_AP message for the CSFB to the base station node 302. The S1_AP message may include an identifier (e_CSFB_indicator) indicating that an improved CSFB, i.e., a quick call setup function, is applied during a CSFB process. In addition, applying the fast call setup function during the CSFB process in the present process and the subsequent process may indicate that information on the PS bearer is not exchanged or set during the CSFB process (CS_only_indicator). The improved CSFB may be a term for describing an embodiment of the present disclosure, and the S1_AP message may include an identifier indicating that the CSFB is applied according to an embodiment of the present disclosure.

When the identifier indicating that the improved CSFB is applicable is transmitted only after confirming whether the user terminal 301, the base station 302, and the core network support the corresponding function, or together with the user's subscription information, It can also be delivered to one. In addition, the S1_AP message may include information indicating that the PS bearer does not need to be handed over during the handover process.

The base station 302 receiving the S1_AP message starts the CSFB process, and if it is possible to apply the enhanced CSFB, that is, the quick call setup function can be applied during the CSFB process. This may be applied only when the S1 AP message received from the MME 304 includes whether to apply the corresponding function. The base station 302 may perform a measurement process with the terminal if necessary, and may select a 2G / 3G (GERAN / UTRAN or 1xRTT) cell to be the target of the CSFB.

The base station 302 does not need a handover for the PS bearer, and when the improved CSFB function is applied, in step 320, the base station 302 indicates to the MME 304 that the CSFB process should proceed (S1-AP response message). Includes one or more of a target base station (RNC or BSC) ID or information indicating that an improved CSFB function is applied. In this case, the improved CSFB, that is, the indicator indicating that the quick call setup function is applied during the CSFB process may be expressed as one value of the CS Fallback Indicator of the message or may be delivered as a separate indicator.

In an embodiment, the message transmitted from the base station 302 to the MME 304 during the above process may be a Handover Required message or a CSFB Required message. In addition, the message transmitted by the base station 302 may include information indicating that a handover for the PS bearer is not required, or indicating that a suspend process for the PS bearer is required.

On the other hand, if the base station 302 determined to proceed with the CSFB process for the user terminal 301 performs the operation of releasing the RRC connection (release) for the user terminal according to the original CSFB operation, if the base station 302 When the improved CSFB process is applied, the RRC connection to the user terminal 301 is not released until the base station 302 receives a separate response message from the MME 304 as shown in step 325. You can start a timer. If the base station 302 does not receive a message for enhanced CSFB operation from the MME 304 until the timer expires, or the message includes information indicating that the MME 304 cannot perform the enhanced CSFB operation. In the case of transmitting the to the base station 302, the base station 302 may perform an existing CSFB operation (redirection information or NACC for moving to a 2G / 3G cell while releasing an RRC connection) with respect to the user terminal 301. This process may be performed in parallel with other processes after the base station 302 informs the CSFB of the need from the MME 304.

At step 330 MME 304 may generate and forward the information to MSC 305 for improved CSFB.

In an embodiment, when the improved CSFB is to be used, the MME 304 generates CK and IK, which are security keys to be used in the CS network, using KASME and, if necessary, NAS counts among the EPS security contexts stored therein. In the embodiment, these CS keys are used for the _CSFB and may be _{referred to} as CK _CSFB and IK _CSFB . It also assigns the value of eKSI to KSI. The MME 304 generates an SGs AP message and transmits it to the MSC 305. The SGs AP message includes an identifier of the user terminal 301, a service identifier, a call type, CS keys generated by the MME, and the like. At least one of information indicating that handover for a KSI or a PS bearer is unnecessary may be included. In this case, the improved CSFB, that is, the indicator indicating that the quick call setup function is applied during the CSFB process may be expressed as a value of the service indicator of the message or may be delivered as a separate indicator. In addition, the message transmitted to the MSC 305 by the MME 304 may be an SGs AP Service Request, an SGs AP CS Handover Request, or an SGs AP CSFB Request message.

In step 335, the MSC 305 uses the received CS key (CK _CSFB , IK _CSFB ) and KSI for the CSFB process. That is, the MSC 305 uses the received CK _CSFB and IK _CSFB as CK and IK. However, if there is already a key (CK, IK, etc.) and KSI stored for the user terminal 301, it can be updated with the Key and KSI received from the MME (304). If the MSC server and the target MSC are separated, the two separated entities may additionally perform the MSC-MSC HO process. If the target cell is GERAN (2G), the MSC 305 can generate and use the GSM CS cipher key Kc or Kc ₁₂₈ from the CS key (CK _CSFB , IK _CSFB or CK, IK).

In an embodiment, the MSC 305 may perform resource allocation by exchanging a Handover Request / Ack message with a 2G / 3G base station.

More specifically, in step 340, the MSC 305 may transmit a Handover Request message to the RNC / BSC 303. In an embodiment, the MSC 305 may inform that the handover for the PS bearer is unnecessary and only CS call resource allocation is required by using the Handover Request message, and the handover request message includes an improved CSFB, that is, a quick call setup function during the CSFB process. An indicator indicating the application may be included.

In step 345, the 2G / 3G base station 303 may allocate resources for the CS call.

In step 350, the 2G / 3G base station 303 includes information including resource usage and cell access information of the 2G / 3G in the target to source transparent container, inserts the container into the Handover Ack message, and delivers the information to the MSC 305. . The handover Ack message or container may include information indicating that an improved CSFB function is applied.

In step 355, the MSC 305 may send an SGs AP response message to the MME 304. The SGs AP response message may include a target to source transparent container received from the 2G / 3G base station 303. In addition, the SGs AP response message or container may include information indicating that an improved CSFB function is applied. In an embodiment, the SGs AP message may be an SGs AP Service Response, an SGs AP CS Handover Response, or an SGs AP CSFB Response.

In step 360, the MME 304 may transmit an S1 AP message instructing the base station 302 to switch the terminal 301 to a 2G or 3G cell. In an embodiment, the S1 AP message may include a target to source transparent container received from the MSC 305. In addition, the S1 AP message or container may include information indicating that an improved CSFB function is applied. In an embodiment, the S1 AP message may be an S1 AP Handover Command message.

In step 365, the base station 302 may transmit an RRC message instructing the terminal 301 to switch to a 2G or 3G cell. The RRC message may include at least one of a target to source transparent container or a CSFB received from the MSC 305. In addition, the identifier indicating that the CSFB may be CS_only_indicator. In this case, the improved CSFB, that is, indicating that the quick call setup function is applied during the CSFB process may be expressed as a value of an identifier indicating that the CSFB is included in the RRC message or may be delivered as a separate indicator. In addition, the RRC message may include an ID (Target ID) of the target cell to which the terminal accesses. In an embodiment, the RRC message may be an RRC HO from E-UTRA Command message.

The terminal 301 attempts to access 2G / 3G according to the command message received from the base station 302.

In step 370, if the user terminal 301 receives information indicating that the current process is an improved CSFB, the user terminal 301 undergoes a process of generating a CS key and KSI. In an embodiment, the process of generating the CS key and the KSI may be performed similarly to the process performed by the MME 304. That is, when the user terminal 301 needs to use the improved CSFB, the user terminal 301 may generate CK and IK, which are security keys to be used in the CS network, using K _ASME and, if necessary, NAS count among the EPS security contexts stored therein. In the embodiment, CS keys are used for _CSFB and may be _{referred to} as CK _CSFB and IK _CSFB . In addition, the terminal 301 may assign a value of eKSI to KSI. If the target cell to be accessed by the user terminal 301 is 2G (GERAN), the user terminal 301 generates a GSM CS cipher key Kc or Kc ₁₂₈ from a CS key (CK _CSFB , IK _CSFB or CK, IK). Can be. The user terminal 301 then uses the generated CS key and KSI when generating and transmitting a message for the CS service (ie, integrity protection or ciphering) or receiving a message (ie, integrity check or decryption). That is, the user terminal 301 uses the CS key (CK _CSFB , IK _CSFB ) and KSI received for the CSFB process thereafter, which uses the CK _CSFB and IK _CSFB received by the terminal 301 as CK and IK. If there is a key (CK, IK, etc.) and KSI already stored by the user terminal 301, the key is updated with the key and KSI received from the MME 304.

In operation 375, the user terminal 301 may transmit at least one of a location update message or a CM service request message to the 2G / 3G base station 303 or the MSC 305. In an embodiment, the user terminal 301 may include the KSI used by the user terminal in a message sent to the 2G / 3G base station 303 or the MSC 305.

In step 380, the 2G / 3G base station 303 or the MSC 305 that has received the message from the user terminal 301 may receive the KSI included in the received message, and may perform integrity check or decryption on the received message. The CS key and KSI described in step 335 may be used.

On the other hand, the MSC (305) may inform the MME (304) through the SGs AP message when the CS call setup is completed, the MME 304 receives the process to release the S1 connection with the base station 302 can do.

In addition, if the handover for the PS bearer is not supported or if it is determined that the suspend operation is required for the PS bearer, the MME 304 deactivates the GBR bearers and suspend the non-GBR bearers. can do. In particular, the timing of performing this process may be determined based on a timer. For example, the MME 304 starts the timer while transmitting a message indicating that the CSFB is needed to the base station 302, and when the timer expires after a certain time. You can do this. Alternatively, the MME 304 may perform the operation when receiving the SGs AP message indicating that the CS call setup is completed from the MSC 305.

On the other hand, since the improved CSFB operation may require a change in the terminal 301, the base station 302, and the core network, the user terminal 301 and each network entity may determine whether the CSFB supports each other in the initial registration process. You can check it.

Referring to FIG. 4, a user equipment (UE) 410, a base station (eNodeB, eNB) 402, a radio network controller (RNC) / base station controller 403, At least one of a mobility management entity (MME) 404 or a mobile switching center (MSC) 405 may transmit and receive a signal. In an embodiment, the RNC / BSC 403 may be referred to as a 2G / 3G base station.

In step 410, when the user terminal 401 performs the registration process for using the CSFB, that is, the Combined attach or Combined TA / LA update process, it indicates that the UE supports the quick call setup function during the improved CSFB process, that is, the CSFB process. The request message may be transmitted to the MME 404 including the information.

In step 415, the MME 404 considers at least one of whether the user terminal 401 supports the corresponding function, whether the base station / core network is supported, and whether the subscription information for the user allows the corresponding function. After determining whether or not to apply, the SGs Location Update Request message transmitted to the MSC 405 is transmitted with the information indicating that the user equipment 401 supports the improved CSFB, that is, the quick call setup function during the CSFB process.

In step 420, when the MSC 405 sends the SGs Location Update Response message to the MME 404, the MSC 405 may include information indicating that the CS core network and the base station support the improved CSFB function.

In step 425, if the MSC 405 also supports the improved CSFB function, the MME 404 stores this as a context for the user terminal 401, and then starts the CSFB process (ie, if the user terminal ( Receive Extended Service Request message from 401), it is possible to determine whether to perform a general CSFB process or to use the quick call setup function of the improved CSFB and CSFB process.

In step 430, the MME 404 includes information indicating whether the network supports the quick call setup function during the CSFB process in the combined attach or TA / LA update accept message transmitted to the user terminal 401. ) Can be delivered.

In step 435, if the user terminal 401 stores the information received in step 430 and the CSFB process occurs and 2G / 3G is switched, whether to set up and use the call setup and CS key according to the above-described embodiment The decision is made.

On the other hand, as mentioned above, supporting the enhanced CSFB, that is, the fast call setup function during the CSFB process, must be supported by both the base station and the core network, so it is necessary to check whether the base station and the core network support each other's improved CSFB. Can be.

Referring to FIG. 5, the base station 501 of the embodiment may transmit and receive a signal with the MME 502.

In step 510, the base station 501, in the process of creating an S1 connection with the core network (MME) 502, informs the S1 Setup Request message of information indicating that it supports an improved CSFB, that is, a quick call setup function during the CSFB process. It may forward to the containing MME 502. In an embodiment, that is, when performing the S1 setup process, the base station 501 can transfer the information to the MME 502.

In operation 515, the MME 502 may determine whether to apply the corresponding function in consideration of at least one of whether the corresponding function supports the core network and whether 2G / 3G is supported. In addition, it is stored as a context for the user terminal, and when the CSFB process is started (that is, an Extended Service Request message is received from the user terminal), whether to perform a general CSFB process or an improved CSFB process Call setup function).

In step 520, the MME 502 may transmit the S1 Setup Response message transmitted to the base station 501 including information indicating that the UE supports the improved CSFB (i.e., the quick call setup function during the CSFB process).

In step 525, the base station 501 stores the information received in step 520, and if a CSFB process occurs and 2G / 3G switching is required, it is determined whether to release the S1 / RRC connection to the user terminal, or It can be used to determine whether to include information on the PS bearer or the Source to Target Transparent Container in the S1 AP message.

If it is confirmed that the user terminal, the base station, and the core network all support the improved CSFB according to the previous two embodiments, and accordingly the preset CSFB is set to use the improved CSFB, the entities exchanged in the foregoing process embodiment Information indicating that the improved CSFB is used is omitted in the message, and it may be determined whether the improved CSFB is applied according to the context stored by each entity.

On the other hand, if SRVCC is applied to a user terminal, the user terminal should inform the network of its SRVCC related information and capabilities, and the core network operates SRVCC using the SRVCC parameter in the subscription information as well as information / capability of the user terminal. Can be performed.

If the user terminal is registered by performing an attach / TAU process with one MME of the operator's network, since the information is stored in the registered MME, the user terminal does not leave the area managed by the corresponding MME. It can support service continuity for voice / video call.

However, if the user terminal leaves the area that was originally managed by the MME, the newly registered MME does not include SRVCC / Capability of the user terminal as well as SRVCC parameters in the subscription information, and thus cannot perform SRVCC.

According to an embodiment of the present disclosure, when an MME in which a user terminal is registered is changed to solve the above problem, the original MME stores the SRVCC-related context / parameters stored in it, in particular, a STN-SR (Session Transfer) for the user terminal. We propose a method for delivering Number for SRVCC) and MS classmark to new MME.

6 is a diagram in which an old MME delivers SRVCC related information when an SRVCC supporting terminal performs Attach / TAU in which an MME is changed according to an embodiment of the present disclosure.

Referring to FIG. 6, at least one entity of the user terminal 601, the first MME (MME1) 602, and the second MME (MME2) 603 may transmit and receive a signal. More specifically, in an embodiment, the old MME may correspond to the MME1 602, and the changed new MME may correspond to the MME2 603.

In step 610, the terminal 601 successfully performs the Attach / TA Update process with the MME1 602, so that the MME1 602 may select at least one of MS classmark (2, 3, or both) or STN-SR for the user terminal. Saving.

In step 615, when the user terminal 601 enters the area of the MME2 603 and performs the Attach or TA update process, the user terminal 601 inserts its MS classmark (2, 3 or both) into the request message. send. The request message may be one of an Attach request or a TAU request.

In operation 620, the new MME 603 transmits a message for requesting a context by searching for an MME originally received by the user terminal 601 using the identifier information of the user terminal 601 and the identifier information of the old MME 602. According to an embodiment, the message for requesting the context may be a context request message.

In step 625, the old MME 601 retrieves the context of the user terminal 601, transfers the context of the user terminal 601 to the new MME 603, and stores the STN-SR for the stored user terminal 601. Can be delivered by inserting In an embodiment, the message transmitting the context may be a context response message.

In step 630, the new MME 603 stores the MS classmark (2, 3 or both) for the user terminal 601 and the STN-SR received from the original MME 602, and then uses this information if SRVCC occurs. Done.

In step 635, the new MME 603 may transmit an Attach / TAU accept message to the user terminal 601.

Referring to FIG. 7, at least one entity of the user terminal 701, the first MME (MME1) 702, the second MME (MME2) 703, and the HSS 704 may transmit and receive a signal. More specifically, in an embodiment, the old MME may correspond to the MME1 702, and the changed new MME may correspond to the MME2 703.

In operation 710, the user terminal 701 may transmit an Attach or TA update request message to the MME1 702. The Attach or TA update request message may include an MS classmark (2, 3, or both) of the user terminal 701.

In step 715, the MME1 702 performs a location registration process (or a subscription information request process) of the user terminal 701 with the HSS 704. In an embodiment, the registration process may be performed by transmitting an Update Location message.

In operation 720, the HSS 704 includes the STN-SR for the user terminal 701 in a message indicating that a location for the user terminal 701 is registered or a message providing user subscription information to the MME1 702. I can deliver it.

In step 725, the MME1 702 may store the received STN-SR and may include the STN-SR in an Attach or TA update acceptance message that transmits the received STN-SR to the user terminal 701.

In operation 730, the user terminal 701 may store the STN-SR received from the MME1 702.

When the user terminal 701 enters the area of the MME2 703 in step 735 and performs an Attach or TA update process, the user terminal 701 has its own MS classmark (2, 3 or both) or the existing MME1 702. At least one of the STN-SRs received and stored from the MS may be inserted into the request message and transmitted to the MME2 703. In an embodiment, the request message may be one of an Attach request message or a TAU request message.

In an embodiment, the new MME 703 may receive a user context from the existing MME 702 if necessary, and in operation 740, the new MME 703 may transmit an Attach / TAU accept message to the user terminal 701. In an embodiment, the Attach / TAU accept message may include the STN-SR of the user terminal 701 stored in the MME2 703.

In step 745 the new MME 703 stores the MS classmark (2, 3 or both) and the STN-SR for the user terminal 701 received from the user terminal 701, and if the SRVCC occurs then based on this information In this way, operations required for SRVCC can be performed.

Referring to FIG. 8, at least one entity of the user terminal 801, the first MME (MME1) 802, the second MME (MME2) 803, and the HSS 804 may transmit and receive a signal. More specifically, in an embodiment, the old MME may correspond to the MME1 802, and the changed new MME may correspond to the MME2 803.

In step 810, if the user terminal 801 registered in the MME1 802 enters the area of the MME2 803 and performs an Attach or TA update process, the user terminal 801 may set its own MS classmark (2, 3 or Both) or at least one of the ID of the previously registered MME may be included in the request message and transmitted to the MME2 (803).

In step 815, the new MME 803 may request a user context by transmitting a user context request message to the existing MME 802 if necessary.

In operation 820, the new MME 803 may receive a user context from the existing MME 802.

In step 825, the new MME 803 performs a location registration process (or a subscription information request process) of the user terminal 801 with the HSS 904. In an embodiment, the new MME 803 may transmit an Update Location Request message to the HSS 804, and the Update Location Request message may include an ID (UE ID) of the user terminal.

In step 830, the HSS 804 includes the STN-SR for the user terminal 801 in a message indicating that a location for the user terminal 801 has been registered, or a message providing user subscription information. Can be forwarded to

In step 835 the new MME 803 stores the received STN-SR, and at least one of the MS classmark (2, 3 or both) or STN-SR for the user terminal 801 received from the user terminal 801 After SRVCC is generated, an operation for performing SRVCC may be performed based on this information.

On the other hand, in another embodiment of the present disclosure, when CSFB generation for the user terminal, other methods for reducing the call setup time is also presented. To this end, first, FIGS. 13 to 15 will be described.

In another embodiment of the present disclosure, in order to shorten call setup time when a CSFB occurs, a cell for performing CSFB before performing a data radio bearer (DRB) setting process and security setting for an access stratum (AS) (Or RAT) change procedure.

Referring to FIG. 13, a user equipment (UE) 1310, a base station (eNodeB, eNB) 1302, a radio network controller (RNC) / base station controller 1303, At least one of a mobility management entity (MME) 1304 or a mobile switching center (MSC) 1305 may exchange signals with another entity. In an embodiment, the RNC / BSC 1303 may be referred to as a 2G / 3G base station.

In operation 1310, the user terminal 1301 is camping on LTE and is operating in an idle mode. At this time, the CSFB for the user terminal 1301 may be triggered. According to an embodiment, the CSFB may be started when a mobile terminating call received by the user terminal 1301 occurs or when a mobile originating call originated by the user terminal 1301 occurs.

In operation 1315, the user terminal 1301 may transmit an Extended Service Request message to the MME 1304 to receive the CSFB service. The Extended Service Request message may include information indicating the type of service (MT CSFB or MO CSFB) that the user terminal 1301 will receive.

In step 1320, the MME 1304 may transmit an initial context setup request message to the eNB 1302 in response to the message received in step 1315. The initial context setup request message may include information indicating that the user terminal 1301 should be moved to UTRAN or GERAN or information indicating that CSFB service is required.

In step 1325, the eNB 1302 needs a CSFB for the user terminal 1301 (ie, the user terminal 1301 should move to UTRAN or GERAN), and the user terminal 1301 is a packet switched handover (PSHO). Determine whether it does not support or do not use.

In an embodiment, if the user terminal 1301 must move the CSFB from the LTE network to the UTRAN or GERAN, if the user terminal 1301 does not support or use the PSHO, the base station 1302 is to set the user terminal DRB The RRC connection reconfiguration message may be transmitted to the 1301 or the UE 1301 may be moved to the UTRAN / GERAN before the Security Mode Command message is transmitted to the UE 1301 in order to configure AS security. have. In an embodiment, the operation for moving the user terminal 1301 to UTRAN / GERAN may include at least one of RRC connection release with redirection, Network Assisted Cell Change (NACC), and Cell Change Order (CCO).

In step 1330, the base station 1302 transmits an Initial Context Setup Response message to the MME 1304. The Initial Context Setup Response message may include information indicating that the CSFB has been triggered or the connection has already been released due to the CSFB. In addition, the Initial Context Setup Response message may include information indicating that all E-RABs for the user terminal 1301 have not been set.

In operation 1335, the base station 1335 may transmit at least one of an RRC connection release message or a CCO / NACC message to the user terminal 1301.

In operation 1340, the MME 1304 may recognize that the CSFB process for the user terminal 1301 is started or E-RAB is not set up based on the message received from the base station 1302. Therefore, the MME 1304 may not perform a process for modifying the bearer context for the SGW and the user terminal 1302. In an embodiment, the MME 1304 may proceed with a bearer setting procedure when a bearer setting is necessary based on the information included in the received message, and when the connection to the terminal 1301 is released, the bearer setting is not necessary. The setting procedure can be omitted.

Thereafter, in step 1345, the user terminal 1301 and the operator's network network may perform the remaining steps for call setup.

The base station of the embodiment may transmit and receive signals with the user terminal and the MME.

In step 1410, the base station may receive an Initial Context Setup Request message from the MME.

In step 1415, the base station may determine whether a CSFB indicator is included in the received message. If the CSFB indicator is included, in step 1420, an operation related to Initial Context Setup may be performed.

In step 1420, the base station may determine whether PSHO is supported or set to be used for the user terminal. If it is necessary to use PSHO, go to step 1430; otherwise, go to step 1425.

In step 1425, the base station may perform the CSFB without PSHO operation before starting the DRB configuration or the AS security configuration. More specifically, before the base station transmits a message for DRB configuration or AS security configuration to the user terminal, an operation for moving the user terminal to GERAN or UTRAN, that is, RRC connection release with redirection, Network Assisted Cell Change (NACC) , Or may perform one of the cell change orders (CCOs).

In step 1430 and step 1435, the base station establishes a DRB with the user terminal and performs an operation for setting AS security.

In step 1440, the base station performs a CSFB with PSHO operation with the user terminal.

In still another embodiment of the present disclosure, in order to reduce call setup time when a voice call is generated for a user terminal using LTE, a user terminal in an idle state is proposed to operate to select a 2G or 3G cell. do.

Referring to FIG. 15, a user equipment (UE) 1501, a base station (eNodeB, eNB) 1502, a radio network controller (RNC) / base station controller 1503, At least one of a mobility management entity (MME) 1504 or a home subscriber server (HSS) 1505 may exchange signals with another entity. In an embodiment, the RNC / BSC 1503 may be referred to as a 2G / 3G base station.

In operation 1510, the user terminal 1501 may transmit a message for registering to the LTE network to the MME. The message for registering in the LTE network may be an attach or TAU request message. In addition, the message may include a Usage setting of the user terminal 1301. In the present embodiment, the Usage setting may be voice centric.

The MME 1504 may recognize that the usage setting of the user terminal is voice centric by the request message received from the user terminal 1501.

In operation 1515, the MME 1504 may receive subscription information about the user terminal 1501 from the HSS 1505. The received subscription information may include a RSP / Rrequency Selection Priority (RFSP) index subscribed to the user terminal.

In step 1520, the MME 1504 has a voice centric usage setting for the user terminal 1501, VoIMS over PS (for example, VoLTE) is not supported for the user terminal, and PSHO is not used for the user terminal. In order to shorten the setup time for the voice call, the user terminal may be configured to select 2G (GERAN) or 3G (UTRAN) RAT or frequency when the UE is idle. More specifically, the terminal may specify a higher priority to select a 2G or 3G network.

In step 1525, the MME 1504 may include the configuration information in a message (initial context setup request or downlink NAS transport) for transmitting to the base station 1502 and transmit the configuration information. That is, the Subscriber Profile Id for RAT / frequency priority (SPID) included in the message may be set to an ID of a profile in which the user terminal 1501 preferentially selects GERAN or UTRAN over E-UTRAN. For example, the SPID may have a value of 255 or 254.

In step 1530, the base station 1502 sets the information so that the user terminal 1501 selects the RAT or frequency of the GERAN or the UTRAN as higher priority than the E-UTRAN in the idle state based on the SPID received from the MME 1504. In step 1535, the user terminal 150 transmits the message to the user terminal 1501. This information may be included in an RRC connection release message transmitted by the base station 1502 to the user terminal 1501, and may be encoded in a redirectedCarrierInfo or idleModeMobilityControlInfo information element.

In operation 1540, the user terminal 1501 may perform an operation for selecting a GERAN or a UTRAN higher than an E-UTRAN in an idle state by using the information received from the base station 1502.

9 is a diagram illustrating a terminal according to an embodiment.

Referring to FIG. 9, a terminal according to an embodiment may include at least one of a transceiver 910, a storage 920, and a terminal controller 930.

The transceiver 910 may transmit and receive a signal with another communication entity including a base station.

The storage unit 920 may store data necessary for the operation of the terminal or information transmitted and received with the other communication entity. More specifically, the terminal may store a security key required for communication, and in the above-described embodiment, may store at least one of information transmitted and received by the terminal.

The terminal controller 930 may control operations of the transceiver 910 and the storage 920. More specifically, the transceiver 910 may be controlled to transmit and receive signals with other communication entities. In addition, the storage unit 920 may be controlled to store the received information, and a security key may be generated based on the received information. In addition, in the above-described embodiment, the control of the overall operation of the terminal may be performed.

10 is a diagram illustrating a base station according to an embodiment.

Referring to FIG. 10, the base station according to the embodiment may include at least one of the transceiver 1010, the storage 1020, and the base station controller 1030.

The transceiver 1010 may transmit and receive signals with other communication entities including the terminal and the MME.

The storage unit 1020 may store data necessary for the operation of the base station or information transmitted and received with the other communication entity. More specifically, information related to whether the network and the UE can support the improved CSFB can be stored, and in the above-described embodiment, at least one of information transmitted and received by the base station can be stored.

The base station controller 1030 may control operations of the transceiver 1010 and the storage 1020. More specifically, the transceiver 1010 may be controlled to transmit and receive signals with other communication entities. In addition, the storage unit 1020 may be controlled to store the received information or information generated based on the received information, determine whether to release the RRC connection, or drive a timer according to the connection establishment and operation accordingly. You can also do In addition, it is possible to perform the control of the overall operation of the base station described in the above-described embodiment.

Referring to FIG. 11, an MME according to an embodiment may include at least one of a transceiver 1110, a storage 1120, or an MME controller 1130.

The transceiver 1110 may transmit and receive signals with other communication entities including a base station, an MSC, and an HSS.

The storage unit 1120 may store data necessary for the operation of the MME or information transmitted / received with the other communication entity. In more detail, information related to the context of the terminal may be stored, and in the above-described embodiment, at least one of information transmitted and received by the MME may be stored.

The MME controller 1130 may control operations of the transceiver 1110 and the storage 1120. More specifically, it controls the transceiver 1110 to transmit and receive signals with other communication entities. In addition, the storage unit 1120 may be controlled to store the received information or information generated based on the received information, store the MS classmark or STN-SR of the terminal received from another MME, and compare the values. MME can be controlled to In addition, it is possible to perform the control of the overall operation of the MME described in the above-described embodiment.

Referring to FIG. 12, the HSS according to the embodiment may include at least one of the transceiver 1210, the storage 1220, or the HSS controller 1230.

The transceiver 1210 may transmit and receive a signal with another communication entity including an MME.

The storage unit 1220 may store data necessary for the operation of the HSS, subscriber information, or information transmitted / received with the other communication entity. More specifically, at least one of information related to the context of the terminal or information of the terminal related to SRVCC may be stored, and in the above-described embodiment, at least one of information transmitted and received by the HSS may be stored.

The HSS controller 1230 may control operations of the transceiver 1210 and the storage 1220. More specifically, the transceiver 1210 may be controlled to transmit and receive signals with other communication entities. In addition, the storage unit 1220 may be controlled to store the received information or information generated based on the received information, and may perform SRVCC based on the UE ID included in the Update Location Request message received from the MME. In order to transmit related STN-SR information to the MME, the entire HSS operation can be controlled. In addition, it is possible to control the overall operation of the HSS described in the above-described embodiment.

Meanwhile, when a telecommunication service network operator and a third party (or service provider) make a contract and provide a service, various new services are possible. For example, instead of providing a 3rd party with the operator and a 3rd party, the sponsored data or billing data in which the 3rd party pays the cost of sending and receiving traffic for the service instead of the user. Alternatively, Sponsored Charging may be available.

For example, if a shopping mall service provider enters into a contract with a telecom operator and introduces a sponsored data service for online shopping, the user may use the service provided by the shopping mall service provider to use the online shopping service without paying a separate communication fee. Due to the increase in the number of users, the shopping mall service provider may expect an increase in the sales of the shopping business or an additional increase in the sales of the online shopping mall.

In an embodiment, the sponsored data service may be applied in a form combined with a subscription to a specific communication service. For example, a service provider providing a communication service and a service provider (3rd party) providing an actual application service are contracted with each other, and the third party pays the communication cost required for the user to use the application service on behalf of the user. May sell to the users a free plan (ie, subscription type) that allows the user to use only certain 3rd party services.

Referring to FIG. 16, a user terminal 1600, a market management server 1606, a subscription manager-secure routing (SM-SR) 1605, and a subscription manager-data preparation (SM-DP) 1604 node are different nodes. It can transmit and receive a signal with at least one of the. In addition, in order to provide such a service, a service provider 1603 and a third party 1602 may establish a service through a contract. In the embodiment, provided to the service provider and the 3rd party operator is an example, which may be universally applied to each operator and the 3rd party.

The entity that sells a combination of 3rd party sponsored data services and communication services is now called an on-demand connectivity (ODC) vendor. The ODC seller may be the same as the telecommunications provider 1603 or the specific 3rd party 1602.

In at least one of steps 1610 and 1612, the service provider 1603 may enter into a communication service sales contract with the ODC seller. At the same time, the 3rd party 1602 service provider may also enter into a service sales contract with the ODC seller. In an embodiment, the ODC seller also acts as a relay for providing sponsored data services between the carrier and the third party. In an embodiment, the ODC seller may be set to correspond to the market management server 1606. In addition, in the following embodiments, a service driving method will be described based on a communication service provider (operator) 1603. This may be performed even when a service of a 3rd party 1602 is provided. Obviously, services can be provided.

In operation 1615, the operator 1603 requests the SM-DP 1604 to generate a subscription profile (hereinafter referred to as a profile) for selling a communication service. The SM-DP may be a function directly operated by the operator 1604 or a function operated by the ODC seller described above.

In step 1620, the SM-DP 1604 transfers the generated profile to the SM-SR 1605. The SM-SR 1605 may be a function operated by the ODC seller described above.

In operation 1625, the communication service provider 1603 and the ODC seller 1606 may exchange information on a product and a profile sold by the ODC seller.

Then, when a user purchases an ODC, performs an operation for executing an ODC (runs an ODC app or accesses an ODC server), in operation 1630, the user terminal 1600 may include information on the user terminal (user terminal identifier-IMEI, At least one of the current location / country of the user terminal 1600 is transmitted to the ODC sales server 1606. In an embodiment, the location information of the user terminal 1600 includes at least one of an IP address of the terminal, an identifier (Cell ID) of a cell communicating with the terminal, and location information determined based on the GPS information received by the user terminal 1600. can do. In addition, additional information for determining the location of the user terminal 1600 may be transmitted to the ODC sales server 1606.

In step 1635, the ODC sales server 1606 selects ODC products according to the received information, and provides ODC product information information that can be provided to the user according to the contract of the telecommunication service provider 1603 and the third party 1602 to the user terminal. send. In an embodiment, the OCD product information may include information for showing usable ODC product information to a user. In an embodiment, the ODC sales server, which may be included in the market management server 1606, may indicate information indicating a specific RAT (Radio Access Technology, LTE / 3G / WiFi, etc.) supported by the user terminal 1600 through an identifier of the user terminal 1600. ) Or only the products of the telecommunications carrier / third party that can provide services at the current location of the user terminal can be performed. In addition, each ODC product information is characterized by including at least one of the following information. More specifically, ODC product information related to a service that may be provided according to the type of the user terminal 1600 or a service that may be selectively provided according to the location of the user terminal 1600 may be transmitted to the user terminal 1600. have. In an embodiment, the market management server 1606 may identify the type of the user terminal 1600 based on the user identifier.

-3rd party service type

-Type of service provider

-Usage fee

-Subscription expiration date (the time from when the purchase of the product is completed and the service is started to expiration)

Maximum amount of data

In other words, the ODC product may provide a user with a list of products that can correspond to a plurality of providers and respective operators. According to an embodiment, a plurality of PLMNs and a list of products provided by each PLMN may be provided to the user, respectively.

As in the embodiment, the user terminal 1600 may display the ODC product list to the user according to the received information, and the user may select one of the ODC products and go through the payment process in step 1640.

If the user purchases the ODC product, in step 1645, the ODC sales server 1606 may transmit a request message to the SM-SR 1605 to transmit a profile for providing the ODC product to the user terminal 1600.

In operation 1650, the SM-SR 1605 may perform a process of transmitting a profile to the user terminal 1600 according to a request 1606 of the ODC sales server. According to an embodiment of the present disclosure, the profile may include at least one of subscription information on OMS and ODC product information, that is, information on sponsored data services provided by a third party. In an embodiment, the user terminal 1600 attaches to the service provider network through the received profile and then receives the sponsored data service for the 3rd party service according to the profile.

Thereafter, in operation 1655, the market management server 1606 may transmit at least one of sales product information and revenue distribution information to the communication service provider 1603.

Meanwhile, in the above embodiment, the ODC sales server 1606, the SM-DP 1604, and the SM-SR 1605 are assumed to be separated from each other. However, the main point of the present invention is that one or more of them are combined. This may also apply. For example, the ODC sales server 1606 and the SM-SR 1605 may be combined into one entity.

Referring to FIG. 17, in an embodiment, a user terminal 1701, an ODC sales server 1702, a subscription manager secure routing (SM-SR) 1703, a subscription manager data preparation (SM-DP) 1704, and an operator network ( A core network (CN) 1705 may transmit and receive signals with each node.

In operation 1715, the SM-DP 1704 may receive a profile generation request from a communication service provider and generate a profile accordingly.

In operation 1720, the SM-DP 1704 may transmit the generated profile to the SM-SR 1703.

In operation 1725, the SM-SR 1703 may store an operator profile received from the SM-DP 1704.

In operation 1705, the user terminal 1701 may transmit a message or information to the ODC sales server 1702 to perform a purchase for a specific ODC product by a user's input.

When the purchase is completed, the ODC sales server 1702 may transmit an access token for the ODC product to the user terminal 1701 in step 1710. The access token may include at least one of an information element including an authority for the ODC product and ODC product information.

In addition, when the ODC product purchase is completed, the ODC server 1702 may transmit a request to the SM-SR 1703 to transmit a profile to the user terminal 1701 in step 1730.

In operation 1735, the SM-SR 1703 may transmit a profile generated according to a request of the ODC server to the user terminal 1701.

In operation 1740, the user terminal 1701 may perform an operation for attaching or registering the service provider network 1705 using the received profile. This process may include at least one of performing authentication with the operator network 1705, obtaining an IP address, receiving a QoS parameter, or requesting a sponsored data service. During this process, the user terminal 1701 may transmit an access token to the operator network 1702.

In operation 1745, the operator network 1705 may verify the validity of the access token received from the user terminal 1701, and if the access token is valid, extract the information of the ODC product, that is, the sponsored data service, from the access token. The extracted information may include at least one of an identifier of a sponsor (3rd party service type) and an address (such as an IP address / port list or a list of URLs) of a server providing the sponsored service.

In operation 1750, the operator network 1705 transmits an access or registration permission message to the user terminal 1701. This message may include information about the ODC product, that is, the sponsored data service. More specifically, the message may include service information (packet filters for distinguishing APN or IP flow) that is allowed to access / use the user terminal 1701.

Thereafter, in step 1755, the user terminal 1701 uses only the service included in the ODC product according to the received allowed service information. That is, the user terminal 1701 may access only a specific APN or a server having a specific address based on the message received in step 1750.

In addition, in operation 1760, the operator network 1705 may also transmit and receive traffic to the user terminal 1601 only for the APNs or addresses that are allowed, and according to the characteristics of the ODC product, charging is not applied to the traffic or sponsored charging. Can be done.

Referring to FIG. 18, in an embodiment, a user terminal 1801, an ODC sales server 1802, an SM-SR 1803, an SM-DP 1804, and a core network (CN) 1805 are respective nodes. Send and receive signals with

The operations of steps 1805 to 1825 may correspond to the operations of steps 1705 to 1825 of FIG. 17, respectively.

The embodiment of FIG. 18 is different from the embodiment of FIG. 17. In the embodiment of FIG. 17, the ODC server generates an access token for an ODC product and transmits it to a user terminal. When the ODC server 1802 requests the SM-SR 1803 to transmit a profile, at least one of the information on the ODC product (the ODC product information described in the embodiment of FIG. 15) is transmitted to the SM-SR 1803. Can be. In more detail, the message requesting profile transmission may be transmitted by including information on the ODC product, or the information on the ODC product may be transmitted to the SM-SR 1803 through a separate message.

Upon receiving this, the SM-SR 1803 generates an access token using the ODC product information in step 1835, includes the same in a profile, and transmits the same to the user terminal 1801.

Subsequently, operations of steps 1840 to 1860 may be performed corresponding to steps 1740 to 1860 of FIG. 17, respectively.

In the above-described embodiments, all steps may optionally be subject to performance or to be omitted. In addition, in each embodiment, the steps need not necessarily occur in order and may be reversed.

On the other hand, the embodiments of the present invention disclosed in the specification and drawings are merely presented specific examples to easily explain the technical contents of the present invention and help the understanding of the present invention, and are not intended to limit the scope of the present invention. That is, it will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention can be implemented.

Claims

In the method of transmitting and receiving signals in a terminal of a mobile communication system,

Transmitting a first message including at least one of an identifier of a terminal and location information of the terminal to a server;

Receiving a second message from the server, the second message including a list of available services determined according to the first message; And

Receiving a connection token for using at least one of the services included in the service list.
The method of claim 1,

The location information of the terminal includes at least one of an IP address of the terminal, an identifier of a cell that transmits and receives a signal with the terminal, and location information received by the terminal from a location related service.
The method of claim 1,

The service list includes a list of services that can be provided to the terminal for each network operator, characterized in that the signal transmission and reception method.
The method of claim 1,

Receiving an access token for using the service

And receiving an access token for using at least one of the services included in the service list from a subscription manager secure routing of the server or the terminal.
In the method of transmitting and receiving a signal in a server of a mobile communication system,

Receiving a first message from the terminal, the first message including at least one of an identifier of the terminal and location information of the terminal;

Transmitting a second message to the terminal, the second message including a list of available services determined according to the first message;

Receiving a third message from the terminal, the third message including information for selecting at least one service from the service list; And

And generating information for using the selected service based on the third message.
The method of claim 5,

The location information of the terminal includes at least one of an IP address of the terminal, an identifier of a cell that transmits and receives a signal with the terminal, and location information received by the terminal from a location related service.
The method of claim 5,

The service list includes a list of services that can be provided to the terminal for each network operator, characterized in that the signal transmission and reception method.
The method of claim 5,

And transmitting the information for using the generated selected service to the terminal or a subscription manager secure routing.
In the terminal of the mobile communication system,

Transmitting and receiving unit for transmitting and receiving a signal; And

Transmitting a first message including at least one of an identifier of a terminal and location information of the terminal to a server, receiving a second message including a list of available services determined according to the first message from the server, and receiving the service list And a control unit controlling the transceiver to receive an access token for using at least one of services included in the terminal.
The method of claim 9,

The location information of the terminal includes at least one of an IP address of the terminal, an identifier of a cell that transmits and receives a signal with the terminal, and location information received by the terminal from a location related service.
The method of claim 9,

The service list terminal, characterized in that it comprises a list of services that can be provided to the terminal for each network operator.
The method of claim 9,

The control unit

And controlling the transceiver to receive an access token for using at least one of the services included in the service list from a subscription manager secure routing of the server or the terminal.
In the server of a mobile communication system,

Transmitting and receiving unit for transmitting and receiving a signal; And

Receiving a first message including at least one of an identifier of a terminal and location information of the terminal from the terminal, transmitting a second message to the terminal, the second message including a list of available services determined according to the first message, and the service And a controller configured to control the transceiver to receive a third message including information for selecting at least one service from a list from the terminal, and to generate information for using the selected service based on the third message. server.
The method of claim 13,

The location information of the terminal includes at least one of an IP address of the terminal, an identifier of a cell that transmits and receives a signal with the terminal, and location information received by the terminal from a location related service.
The method of claim 13,

The service list server, characterized in that it comprises a list of services that can be provided to the terminal for each network operator.
The method of claim 13,

The control unit

And controlling the transceiver to transmit information for using the generated selected service to the terminal or a subscription manager secure routing.