CN100407876C - A user equipment attachment method - Google Patents

Abstract

The present invention is applicable to the field of mobile communication, and provides a method for attaching user equipment. The method includes: the core network receives an attach request message sent by the user equipment, and the attach request message carries information that the user equipment needs to call a session control agent function entity Indication information of the IP address of the P-CSCF; the core network obtains the IP address of the call session control proxy functional entity P-CSCF; the core network sends an attach accept message to the user equipment, and the attach accept message carries the call session IP address of the P-CSCF of the control proxy functional entity. The invention acquires the IP address of the P-CSCF during the attaching process of the UE, and the UE can perform IMS registration after the attaching is completed, which can simplify the signaling process of establishing the service connection of the user and reduce the service connection time delay.

Description

A user equipment attachment method

technical field

The invention belongs to the communication field, and in particular relates to a user equipment attachment method.

Background technique

The existing GPRS (General Package Radio Service, General Packet Radio Service)/UMTS (Universal Mobile Telecommunications System, Universal Mobile Communications System) network structure is shown in Figure 1, which adopts a structure similar to that of the second-generation mobile communication system, including UMTS (Universal Mobile Telecommunications System, Universal Mobile Communication System) Terrestrial Radio Access Network (UMTSTerritorial Radio Access Network, UTRAN), GSM/EDGE Radio Access Network (GSM/EDGE Radio Access Network, GERAN), Core Network (Core Network, CN) And user equipment (User Equipment, UE). Among them, GERAN/UTRAN is used to implement all wireless-related functions, while CN handles all voice calls and data connections in the GPRS/UMTS system, and is used to implement switching and routing functions with external networks. CN is logically divided into Circuit Switched Domain (CS) and Packet Switched Domain (PS), which support voice and data services respectively.

The CS domain includes nodes such as Mobile Switching Center Server (MSC-Server), Media Gateway (MGW) and Gateway Mobile Services Switching Center Server (GMSC-Server). Among them, the MSC-Server is used to transmit the control plane data of the CS domain, and implement functions such as mobility management, call control, and authentication and encryption. The GMSC-Server is used to implement the control plane functions of the GMSC call control and mobility control. To realize the transmission of user plane data;

The PS domain includes nodes such as the Serving General Packet Radio Service Support Node (SGSN) and the Gateway General Packet Radio Service Support Node (GGSN). Among them, the GGSN is mainly responsible for the interface with the external network, and at the same time, the GGSN is also responsible for the transmission of user plane data. The position of the SGSN in the PS domain is similar to that of the MSC Server in the CS domain, and its core functions are to implement functions such as routing and forwarding, mobility management, session management, and user information storage.

The Home Location Register (HLR) is used to store user subscription information, and both the CS and PS domains use this device.

3GPP (Third Generation Partnership Project, Third Generation Partnership Project) superimposed the IMS (IP Multimedia Core Network Subsystem, IP Multimedia Core Network Subsystem) network on the basis of the existing PS domain network, as shown in Figure 2, the introduction of session As a service control protocol, Session Initiation Protocol (SIP) utilizes the characteristics of SIP's simplicity, easy expansion, and convenient media combination to provide rich multimedia services by separating service control from bearer control. For more descriptions about IMS, please refer to the protocol 3GPP TS 23.228 v6.10.0, which is cited in the present invention and will not be repeated here.

Among them, the Call Session Control Function entity (Call Session Control Function, CSCF) is the core processing component of the IMS network, and is used to control functions such as user registration and session control. According to the function, it includes three logical entities: CSCF proxy function entity (Proxy CSCF, P-CSCF), CSCF query function entity (Interrogating CSCF, I-CSCF) and CSCF service function entity (Serving CSCF, S-CSCF).

The P-CSCF is the unified primary entry point of the IMS visited domain control plane, which realizes the proxy transfer of SIP messages (such as registration, multimedia sessions, etc.) information recorded at time) or I-CSCF (according to the home domain name carried by the SIP user agent) and other functions.

The I-CSCF is the initial unified entry point of the IMS home domain control plane. During the IMS registration process, an S-CSCF is assigned to the user according to the user subscription and CSCF capability information returned by the home network server (Home Subscriber Server, HSS). The registration request is forwarded to the S-CSCF, and is also responsible for reselecting the S-CSCF when the expected response from the S-CSCF is not received within the timeout period.

The S-CSCF is in the core control position in the session control of the entire IMS core network. It has the ability to accept the registration request forwarded by the P-CSCF from the user in the IMS visited domain, cooperate with the HSS to authenticate the IMS user equipment user, and obtain the information from the HSS. Download IMS basic subscription data, perform basic session routing functions for calling and called IMS users, and evaluate IMS subscription trigger rules and other functions;

The HSS is used to save the subscription information of the IMS user in the home network, and is located in the top layer of the IMS core network architecture as a database for storing user information in the IMS. Including basic identification, routing information, and service contract information.

In order to enhance the competitiveness of future networks, 3GPP is studying an evolved 3GPP network system. An evolved packet core network architecture is shown in Figure 3, including a mobility management entity (Mobility Management Entity, MME), a user plane entity (User Plane Entity, UPE) and a user plane anchor point (Inter Access System Anchor, Inter AS Anchor) three logical functional entities. Among them, the MME is responsible for the mobility management of the control plane, including user context and mobility state management, and assigning temporary user IDs, etc., corresponding to the control plane part of the SGSN in the current GPRS/UMTS system; the UPE is responsible for initiating search for downlink data in the idle state Call, manage and save IP bearer parameters and intra-network routing information, etc., corresponding to the data plane part of SGSN and GGSN in the current GPRS/UMTS system; Inter AS Anchor acts as the user plane anchor point between different access systems. The billing and policy control module (Policy and Charging Rule Function, PCRF) is used for billing and policy control. A home network server (Home Subscriber Server, HSS) is used to store user subscription information.

According to the requirements of the evolved packet core network, when the UE is attached, a default IP access service can be provided between the UE and the evolved packet core network. The default IP access service allows the UE to register with the IMS system, so It is required that the UE can obtain the IP address of the P-CSCF after attaching to register in the IMS system.

Figure 4 shows the implementation process of user attachment in 3GPP TR23.882, which is detailed as follows:

1. The UE sends a network discovery and access system selection message (Network Discovery and Access System Selection) to the evolved access network (Evolved RAN) to select the network and access system;

2. The UE sends an Attach Request message (Attach Request) to the MME/UPE;

3. If the attachment request message carries the registration information of the old side, the MME/UPE sends the original registration information (Send old registration information) to the old side MME/UPE to obtain the user information;

4. The old side MME/UPE sends user information (Send user information);

5. The new side MME/UPE performs authentication on the UE (Authentication);

6. Register the new side MME/UPE into the HSS (Register MME/UPE);

7. Delete UE registration information on the old side MME/UPE (Delete UE registration information);

8. HSS confirms the registration of the new MME/UPE (Confirm Registration);

9. MME/UPE selects an Inter AS Anchor (Selection of Intersystem Mobility Anchor GW);

10. Inter AS Anchor uses UE's assigned IP address for IP layer configuration, the user plane between UE and Inter AS Anchor is established, and the default charging and policy rules are used (User Plane RouteConfiguration);

11. Configure the QoS (Configure IP Bearer QoS) used by the default IP access bearer between the MME/UPE and the evolved access network;

12. MME/UPE accepts the UE's Attach Request (Attach Accept) and assigns the UE's temporary identity;

13. The UE confirms that the attachment is successful (Attach Confirm).

It can be seen from the above process that the UE cannot obtain the IP address of the P-CSCF during the attach process, and cannot register in the IMS after the attach is completed.

Contents of the invention

The purpose of the present invention is to provide a user equipment attachment method, aiming to solve the problem in the prior art that UE cannot know the IP address of P-CSCF during the attachment process, resulting in the failure to register in the IMS after the attachment is completed.

The purpose of the present invention is achieved in this way, a user equipment attachment method, the method includes the following steps:

A. The user equipment sends an attach request message to the core network, and the attach request message carries indication information that the user equipment needs to call the IP address of the session control proxy function entity P-CSCF;

B. The core network obtains the IP address of the call session control proxy functional entity P-CSCF;

C. The core network sends an attach accept message to the user equipment, where the attach accept message carries the IP address of the call session control proxy functional entity P-CSCF.

The indication information is carried by the mobile station network capability information element MS networkcapability in the attach request message.

The core network acquires the IP address of the call session control proxy function entity P-CSCF according to the access point name (APN) used by the user equipment.

After said step C, said method further comprises:

D. The user equipment saves the IP address of the call session control proxy functional entity P-CSCF.

The invention obtains the IP address of the P-CSCF during the attaching process of the UE, and the UE can perform IMS registration after the attaching is completed, which can simplify the signaling process of establishing the service connection of the user and reduce the service connection time delay.

Description of drawings

FIG. 1 is a network architecture diagram of an existing GPRS/UMTS;

Figure 2 is a network architecture diagram with IMS superimposed on the basis of the existing PS domain network;

FIG. 3 is an architecture diagram of an evolved packet core network;

FIG. 4 is a flow chart of implementing UE attachment in an evolved packet core network in the prior art;

Fig. 5 is a flow chart of the implementation of UE attachment in the evolved packet core network in the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The present invention obtains the IP address of the P-CSCF in the process of UE attachment in the evolved packet core network, and can register in the IMS after the user equipment attaches, so that the evolved packet core network can provide a default IP address after the UE attaches. IP access service.

FIG. 5 shows the implementation process of the UE attaching in the evolved packet core network in the present invention, which is described in detail as follows:

1. The UE sends a network discovery and access system selection message (Network Discovery and Access System Selection) to the evolved access network (Evolved RAN) to select the network and access system;

2. The UE sends an attach request message to the MME/UPE, and the attach request message carries indication information whether the UE needs the IP address of the P-CSCF;

As an embodiment of the present invention, the MS network capability (MS network capability) information element in the attach request message carries the indication information of whether the UE needs the IP address of the P-CSCF, specifically, it may be to add a P-CSCF flag bit IP Indicator Information used to indicate whether the UE needs the IP address of the P-CSCF. When this flag is 1, it means that the MS needs a P-CSCF IP address (Mobile station needP-CSCF IP address); when this flag is 0, it means that the MS does not need a P-CSCF IP address (Mobilestation need not P-CSCF IP address), the example structure of the MS network capability cell is as follows:

<MS network capability value part>:＝<GEA1 bits><SM capabilities via dedicated channels:bit><SM capabilities via GPRS channels:bit><UCS2 support:bit><SS Screening Indicator:bit string(2)><SoLSA Capability:bit><Revision level indicator:bit><PFC feature mode:bit><Extended GEA bits><LCS VA capability:bit><P-CSCF IP Indicator:bit><Spare bits>; … P-CSCF IP Indicator0 Mobile station need not P-CSCF IP address

1 Mobile station need P-CSCF IP address

3. If the attachment request message carries the registration information of the old side, the MME/UPE sends the original registration information (Send old registration information) to the old side MME/UPE to obtain the user information;

4. The old side MME/UPE sends user information (Send user information);

5. The new side MME/UPE performs authentication on the UE (Authentication);

6. Register the new side MME/UPE into the HSS (Register MME/UPE);

7. Delete UE registration information on the old side MME/UPE (Delete UE registration information);

8. HSS confirms the registration of the new MME/UPE (Confirm Registration);

9. MME/UPE selects an Inter AS Anchor (Selection of Intersystem Mobility Anchor GW);

10. The Inter AS Anchor uses the assigned IP address of the UE for IP layer configuration, the user plane between the UE and the Inter AS Anchor is established, the default charging and policy rules are used, and the evolved packet core network obtains the configuration of the P-CSCF IP address;

As an embodiment of the present invention, the evolved packet core network can configure the IP address of the P-CSCF used by each APN (AccessPoint Name, access point name), and the evolved packet core network obtains the IP address used by the UE according to the APN used by the UE. IP address of the P-CSCF.

It should be noted that the IP address configuration of the P-CSCF is the internal configuration of the evolved packet core network, which is related to the design of the network and the operation strategy of the operator, and is not limited by the present invention.

11. Configure the QoS (Configure IP Bearer QoS) used by the default IP access bearer between the MME/UPE and the evolved wireless access network;

12. The MME/UPE accepts the UE's attach request (Attach Accept) and assigns the UE's temporary identity. At the same time, the MME/UPE evolved packet core network carries the IP address of the P-CSCF it has acquired to the UE in the Attach Accept message. The UE saves the IP address of the P-CSCF;

As an embodiment of the present invention, by adding the P-CSCF IP address information element to carry the IP address of the P-CSCF in the Attach Accept message, the following includes an example structure of the Attach Accept message of the P-CSCF IP address information element:

IEI (Information Element Identification) Information Element Protocol discriminator Skip indicator Attach accept message identity Attach result Force to standby Periodic RA update timer Radio priority for SMS Radio priority for TOM8 Routing area identification 19 P-TMSI signature 17 Negotiated READY timer value 18 Allocated P-TMSI twenty three MS identity 25 GMM cause 2A T3302 value 8C Cell Notification 4A Equivalent PLMNs B- Network feature support 34 Emergency Number List 35 P-CSCF IP address

13. The UE confirms that the attachment is successful (Attach Confirm);

14. The UE uses the obtained IP address of the P-CSCF to register with the IMS. For the registration process, please refer to 3GPPTS 23.228, which is referenced here in the present invention and will not be repeated here.

It should be noted that in the above process, the IP address of the P-CSCF obtained by the evolved packet core network is completed in step 10, which is not limited to this in actual implementation.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (4)

1. a user's device attaching method is characterized in that, described method comprises:

A. core net receives the Attach Request message that subscriber equipment sends, and carries the indication information that subscriber equipment needs the IP address of call session control agent functional entity P-CSCF in the described Attach Request message;

B. core net is obtained the IP address of described call session control agent functional entity P-CSCF;

C. core net sends to adhere to subscriber equipment and accepts message, the described IP address of accepting to carry in the message described call session control agent functional entity P-CSCF of adhering to.

2. user's device attaching method as claimed in claim 1 is characterized in that, described indication information carries by the MS network capability cell MS network capability in the Attach Request message.

3. user's device attaching method as claimed in claim 1 is characterized in that, described step B comprises:

Core net is obtained the IP address of described call session control agent functional entity P-CSCF according to the employed Access Point Name APN of subscriber equipment.

4. user's device attaching method as claimed in claim 1 is characterized in that, after described step C, described method further comprises:

D. subscriber equipment is preserved the IP address of described call session control agent functional entity P-CSCF.

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