CN100413273C - Method for global microwave access interoperability network to access Internet protocol multimedia subdomain - Google Patents

Abstract

The present invention discloses a method for accessing a WiMAX network to an IMS domain. The address information of a PDG of a 3G network is stored in a domain name server DNS in the WiMAX network in advance. The method comprises the steps that a UE and the DNS of the WiMAX network interact after the UE is accessed into the WiMAX network so as to obtain the address information of the PDG for providing service; the UE obtains the address information of a P-CSCF entity in the IMS domain through the WiMAX network and the PDG; the UE and an S-CSCF entity in the IMS domain interact through the WiMAX network, the PDG and the P-CSCF so as to establish session connection between the UE and the IMS domain. The access of the WiMAX network to the IMS domain can be realized by applying the method of the present invention so as to be favorable for the generalization of WiMAX technology.

Description

Method for global microwave access interoperability network to access Internet protocol multimedia subdomain

technical field

The invention relates to the wireless broadband access technology, in particular to a method for accessing the Internet Protocol Multimedia Subdomain (IMS) through a Worldwide Interoperability for Microwave Access (WiMAX) network.

Background technique

According to the 3GPP R5 protocol, the Universal Mobile Telecommunications System (UMTS) core network (CN) can be logically divided into circuit domain (CS), packet domain (PS) and IMS domain. Among them, the CS domain is composed of entities such as Mobile Switching Center (MSC), which is responsible for providing circuit-type services or related signaling connections for users; the PS domain is composed of entities such as Serving General Packet Radio Service Support Node (GGSN), which is responsible for providing packet-based data services for users; the IMS domain uses the PS domain as the bearer network, and is a standardized multimedia service solution provided on top of the packet-switched bearer. It consists of a home location server ( HSS) and call session control function (CSCF) entities, etc., realize the session connection and data transmission of Internet protocol (IP) multimedia services, and realize real-time and non-real-time multimedia services such as audio, video, text, etc. together with the packet domain, Realize the goal of migrating voice services from narrowband to broadband, and provide a common network architecture for future IP multimedia applications, facilitating the realization of new services.

As shown in Figure 1, in the IMS framework stipulated in the R5 protocol, the main functional entities include: CSCF entity, Breakthrough Point Gateway Control Function (BGCF) entity, Media Gateway Control (MGCF) entity, Multimedia Resource Function Control (MRFC) entity , an IMS Media Gateway Function (IMS-MGW) entity, a Multimedia Resource Function Processing (MRFP) entity, a Subscription Location Function (SLF) entity, and an HSS entity. The functions of each entity are as follows:

1. CSCF entities: including proxy CSCF (P-CSCF), serving CSCF (S-CSCF) and interrogation CSCF (I-CSCF). Among them, the P-CSCF entity is the first connection point with the user in the IMS, and the session initiation protocol (SIP) is used between the user equipment (UE) and the P-CSCF entity to implement multimedia session management functions such as session establishment, modification, and termination. , and the P-CSCF entity can also provide the user agent (UA) function, that is, interrupt or independently generate a SIP session under abnormal circumstances; the S-CSCF entity is in the core control position in the IMS domain, and is responsible for registration, authentication and Session control, implement the basic session routing function for the calling end and called end IMS users, and perform value-added service routing triggering and service control interaction to the authentication server (AS) when the conditions are met according to the IMS triggering rules signed by the users; The I-CSCF entity is similar to the gateway node of IMS, and provides functions such as local user service node allocation, route query, and IMS inter-domain topology hiding.

2. BGCF entity: According to the interworking rule configuration or the called party analysis, select the MGCF entity for the call from the IMS domain to the public switched telephone network (PSTN)/CS domain, so as to realize the automatic acquisition of the MGCF route.

3. MGCF entity: Realize the interaction between the IMS core control plane and the CS domain in the PSTN or public land mobile network (PLMN), and support the integration of the integrated service quality network user part (ISUP)/BICC (call control protocol independent of bearer) and SIP Protocol interaction and call interworking, controlling the IMS-MGW entity to complete the real-time conversion between the TDM bearer in the PSTN or CS domain and the user plane RTP (Real-time Transport Protocol) in the IMS domain.

4. MRFC entity: controls the media resources on the MRFP entity, parses SIP resource control commands from other S-CSCF entities and ASs, converts them into corresponding control commands of MRFP, and generates corresponding charging information.

5. IMS-MGW entity: complete IMS, PSTN and user plane broadband and narrowband bearer intercommunication in CS domain, and necessary codec conversion.

6. MRFP entity: As a network public resource, it controls the IP user plane bearer connection with other IMS terminals or IMS-MGW, and provides resource services under the control of the MRFC entity, such as media stream mixing, multimedia information playback, and media content analysis processing etc.

7. SLF entity: In the case of multiple HSS entities, provide the I-CSCF entity with the HSS domain name where the user subscription data is located in the process of registration and transaction establishment.

8. HSS entity: HSS is the main database of mobile users in the network, which stores the subscription information of IMS users, including basic identification, routing information and service subscription information, etc., and is located at the top layer of the IMS domain core network architecture.

In the IMS domain composed of the above-mentioned entities, the access network such as the WiMAX network establishes a connection with the P-CSCF entity to achieve the purpose of accessing the IMS domain, and then can perform various services provided by the IMS.

The WiMAX network is a network stipulated in the IEEE802.16 standard promulgated by the Institute of Electrical and Electronics Engineers (IEEE) in December 2001, and is used to provide the last mile wireless broadband access in the metropolitan area network. The transmission speed of the WiMAX network can reach 70Mbps, and the coverage can reach 50 kilometers. The network can not only connect portable or mobile users to the Internet through wireless broadband access technology, but also connect companies and homes to wired backbone lines, and can also be used as a wireless local area network (WLAN) hotspot and the second generation (2G) Or the base station backhaul link of the third generation (3G) mobile communication system.

Although the above-mentioned WiMAX network has such superior performance, the 802.16 standard only specifies the physical layer (PHY) and media access control layer (MAC) of the WiMAX network, but does not specify the access of the WiMAX network to the IMS domain of the core network. method. Currently, users of the WiMAX network cannot enjoy various services provided by the IMS domain, and operators cannot obtain benefits from the above-mentioned users. Therefore, the seamless coverage of user-oriented mobile communication networks cannot be realized through the WiMAX network. At the same time, the enthusiasm of operators to build WiMAX networks is not high, which is not conducive to accelerating the promotion of WiMAX technology.

Contents of the invention

In view of this, the purpose of the present invention is to provide a method for a WiMAX network to access an IMS domain, enabling a user to access an IMS domain through a WiMAX network.

To achieve the above object, the present invention provides a method for WiMAX network access to the IMS domain, storing the address information of the packet data gateway PDG of the third generation 3G network in advance in the domain name server DNS of the WiMAX network, the method comprising the following steps:

A. After the user equipment UE accesses the WiMAX network, it interacts with the DNS of the WiMAX network to obtain the address information of the packet data gateway PDG that provides the service;

B. The UE requests the DHCP server for the proxy call session control function P-CSCF domain name in the IMS domain assigned to the UE through the WiMAX network and the PDG, and sends the P-CSCF domain name to the 3G network DNS, obtaining the address information of the P-CSCF entity;

C. The UE requests registration from the serving call session control function S-CSCF entity in the IMS domain through the WiMAX network, the PDG, and the P-CSCF, and the S-CSCF notifies the UE to pass identity and authority verification. The UE requests the S-CSCF to establish a session connection between the UE and the IMS domain.

Wherein, the method for the user equipment UE described in step A to access the WiMAX network includes:

A11.UE is connected to the WiMAX network through the base station BS;

A12. The UE obtains the local access Internet protocol IP address of the UE in the WiMAX network from the access gateway ASN GW through the BS, and uses the obtained IP address as the source address to route to the WiMAX network.

Wherein, between step A11 and step A12, the method further includes:

The authentication server AS performs access authentication on the UE, and judges whether the access authentication is successful, and if so, proceeds to step A12; otherwise, ends the process of accessing the IMS domain.

Wherein, the method for the AS to perform access authentication on the UE is as follows:

UE first submits its own user identity to AS through BS and ASN GW, and AS obtains authentication set and user subscription information from home location server HSS, and according to the received user identity, authentication set and user subscription information, Perform access authentication on the UE to obtain an access authentication result;

The method for judging whether the access authentication is successful is:

If the access authentication result is successful, it is determined that the access authentication is successful; otherwise, it is determined that the access authentication fails.

Wherein, the method for obtaining the address information of the PDG that provides the service described in step A is: the UE interacts with the DNS of the WiMAX network through the base station BS and the access gateway ASN GW in the WiMAX network, and obtains the address of the packet data gateway PDG that provides the service information.

Wherein, the method for obtaining the address information of the PDG that provides the service includes:

A21.UE sends the domain name of PDG to DNS of WiMAX network through BS and ASN GW;

A22. The DNS of the WiMAX network uses the received PDG domain name as an index, searches the corresponding relationship between the stored PDG domain name and PDG address information, determines the PDG address information corresponding to the PDG domain name, and passes the BS and ASN GW , returning the found PDG address information to the UE.

Wherein, after the step A22, the method further includes:

The UE establishes a secure tunnel between itself and the PDG according to the acquired address information of the PDG.

Wherein, the address information of the PDG is: the IP address of the PDG.

Wherein, the address information of the P-CSCF is: the IP address of the P-CSCF.

By applying the present invention, the WiMAX network can be accessed into the IMS domain. Specifically, the present invention has the following beneficial effects:

1. In the present invention, the UE gradually determines the IP addresses of the PDG and P-CSCF through the WiMAX network, and then establishes a session connection with the IMS domain to carry IMS-related service data, thereby realizing the purpose of WiMAX access to the IMS domain. In addition, since operators can obtain profits from WiMAX users, the enthusiasm of operators to build WiMAX networks is increased, which is conducive to the promotion of WiMAX technology.

2. The present invention establishes secure tunnels between the UE and the PDG and between the UE and the P-CSCF, so that after the WiMAX network is successfully connected to the IMS domain, the multimedia session between the UE and the IMS domain is transmitted based on the secure tunnel, The security and reliability of data transmission are guaranteed.

3. The present invention utilizes the HSS in the 3G network to save the user's identity information and authority information, which is beneficial to the unified billing, unified maintenance and unified operation of the 3G network and the WiMAX network.

Description of drawings

FIG. 1 is a network architecture diagram of an existing IMS domain;

Fig. 2 is a network architecture diagram of a WiMAX network accessing an IMS domain in an embodiment of the present invention;

FIG. 3 is a flowchart of a method for a WiMAX network to access an IMS domain in an embodiment of the present invention.

Detailed ways

In order to make the purpose and technical solution of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and examples.

The present invention is a method for accessing an IMS domain by a WiMAX network. The address information of a packet data gateway PDG of a third-generation 3G network is stored in advance in a domain name server DNS of the WiMAX network. The method includes the following steps:

A. After the user equipment UE accesses the WiMAX network, it interacts with the DNS of the WiMAX network to obtain the address information of the packet data gateway PDG that provides the service;

B. The UE obtains the address information of the proxy call session control function P-CSCF entity in the IMS domain through the WiMAX network and the PDG;

C. The UE interacts with the Serving Call Session Control Function (S-CSCF) entity of the IMS domain through the WiMAX network, the PDG and the P-CSCF, and establishes a session connection between the UE and the IMS domain.

Taking the IP address of the PDG as the address information of the PDG and the IP address of the P-CSCF as the address information of the P-CSCF as an example, the system architecture and specific process of WiMAX network access to the IMS domain are described below.

Specifically, as an embodiment of the present invention, the network architecture shown in FIG. 2 is used to achieve the purpose of accessing the WiMAX network to the IMS domain. Among them, the IMS domain mainly includes P-CSCF, S-CSCF, and I-CSCF entities, and is located in the 3G network including AS, HSS, DNS, DHCP, and PDG, and the IMS domain communicates with the DNS and DNS in the 3G network through the PDG. The interaction of the DHCP entity, and authentication of the users of the access network connected to the 3G network through HSS; the WiMAX network mainly includes BS, ASN GW and DNS entity, and the ASN GW realizes the connection with the HSS entity through the AS in the 3G network Interaction, and through PDG, realize the interaction with DNS, DHCP and IMS in the 3G network. In the above network architecture, the specific functions of each entity are as follows: BS is responsible for providing WiMAX wireless access for UE; ASN GW is responsible for wireless resource management of WiMAX network, mobile management, and statistics related to authentication, authorization and charging; AS and The HSS is responsible for authenticating, authorizing, and billing UEs in the WiMAX network; DNS stores the correspondence between PDG domain names and PDG IP addresses, and the correspondence between P-CSCF domain names and P-CSCF IP addresses, and according to the received domain name, and provide UE with the IP address of the corresponding PDG or P-CSCF; PDG is responsible for using Internet Protocol Security (IPsec) and other technologies to securely process received and sent data, and provides Dynamic Address Assignment Protocol (DHCP) relay (Relay ) function, so that the UE can find the P-CSCF through the PDG; the DHCP server is responsible for assigning the remote IP address and the domain name of the P-CSCF to the UE.

As shown in Figure 3, the method for the WiMAX network to access the IMS domain in this embodiment includes the following steps:

Step 301. The UE connects to the WiMAX network through the BS.

In this step, the UE cooperates with the BS to perform operations such as physical synchronization, adjustment of time offset, frequency offset and transmit power, and capability negotiation, so as to connect to the WiMAX network.

Step 302. The UE submits its own user identity to the AS through the BS and the ASN GW, and the AS performs access authentication on the UE, and returns the access authentication result to the UE; judges whether the access authentication result is successful, and if so, then Execute step 303, otherwise, end this access procedure.

In this step, UE firstly submits user identification such as mobile phone number to AS through BS and ASN GW; AS then obtains authentication set and user subscription information from HSS, and according to the received user identification, authentication set and user The subscription information is used to perform access authentication on the UE; then, the AS returns the access authentication result to the UE through the ASN GW and the BS.

And, if the access authentication result is successful, it indicates that the UE is allowed to use the WiMAX network; otherwise, it indicates that the UE is not authorized to use the WiMAX network.

Step 303. The UE obtains the local access IP address of the UE in the WiMAX network from the ASN GW through the BS, and uses the obtained IP address as the source address to route to the WiMAX network.

In this step, the UE first requests the ASN GW to allocate a local access IP address for itself; then, the ASN GW returns the local access IP address of the UE to the UE according to the received request, so that the UE can be related to WiMAX network services thereafter In the message, the obtained local access IP address is used as the source address to access the WiMAX network.

So far, the UE has completed the whole process of accessing the WiMAX network, and thereafter, the UE can interact with the WiMAX network to realize wireless communication.

Steps 304-305. The UE obtains the IP address of the PDG providing the service from the DNS of the WiMAX network through the BS and the ASN GW, and establishes a secure tunnel between the UE and the PDG according to the obtained IP address.

In order to realize the connection between the UE and the PDG, in this embodiment, the IP address of the PDG providing the service is stored in the DNS of the WiMAX network in advance. The method for the UE to obtain the IP address of the PDG here is: first, the UE sends the domain name of the PDG to the DNS of the WiMAX network through the BS and the ASN GW; the DNS of the WiMAX network takes the received PDG domain name Retrieve in the corresponding relationship with the IP address of the PDG, determine the IP address of the PDG corresponding to the PDG domain name, and return the found IP address of the PDG to the UE through the BS and the ASN GW.

In addition, here, the PDG domain name sent by the UE can be in various ways, for example: MSISDN.realm, where the MSISDN part represents the identity of the UE, and the realm part represents the domain where the PDG is located.

After the UE obtains the IP address of the PDG, it requests the PDG to establish a secure tunnel with the UE according to the obtained IP address; after receiving the request from the UE, the PDG uses technologies such as IPsec to establish a secure tunnel with the UE. Secure tunnel, and notify UE after successful establishment. For example, in the IPsec mode, the PDG establishes a secure tunnel by determining the security parameters with the UE and distributing keys to the UE, so as to perform security processing on the data transmitted on the secure tunnel and enhance the security of data exchange. safety and reliability.

Step 306. The UE requests the DHCP server to assign a remote IP address and P-CSCF domain name to the UE through the BS, ASN GW and PDG. The DHCP server passes the remote IP address and P-CSCF domain name list through the PDG and ASN according to the received request. GW and BS return to UE.

In this step, the UE first sends the request to obtain the remote IP address and P-CSCF domain name to the PDG through the BS and the ASN GW, and the PDG executes the DHCP Relay to forward the received request to the DHCP server; the DHCP server receives the request from the PDG After the request, the assigned remote IP address and P-CSCF domain name list are returned to PDG, and PDG forwards the obtained remote IP address and P-CSCF domain name list to UE through ASN GW and BS. After the UE has obtained its own remote IP address, it will use the remote IP address as the source address of the message related to the IMS domain service in the subsequent communication process with the IMS domain; in addition, since the UE has obtained the P-CSCF domain name list, then in subsequent steps, the IP address of the P-CSCF can be determined according to the P-CSCF domain name selected from the list.

Step 307. The UE sends the P-CSCF domain name to the DNS of the 3G network through the BS, ASN GW and PDG, and requests the DNS to provide the IP address of the P-CSCF. The DNS of the 3G network then passes the ASN GW and BS to send the P-CSCF The IP address is returned to the UE.

In this step, the UE first selects the P-CSCF domain name from the received list according to its own configuration, and sends the selected P-CSCF domain name to the DNS of the 3G network through the BS and ASN GW, and requests to obtain the P-CSCF domain name. The IP address of the P-CSCF corresponding to the CSCF domain name; after receiving the request, the DNS of the 3G network uses the P-CSCF domain name provided by the UE as an index to search in the stored correspondence between the P-CSCF domain name and IP address, Find the IP address of the corresponding P-CSCF and return it to the UE.

Step 308. The UE establishes a secure tunnel between itself and the P-CSCF according to the received IP address of the P-CSCF.

In this step, the UE requests the P-CSCF to establish a secure tunnel with the UE through the BS, ASN GW and PDG according to the obtained IP address of the P-CSCF; after the P-CSCF receives the request from the UE, Use technologies such as IPsec to establish a secure tunnel with the UE, and notify the UE through the PDG, ASN GW and BS after the establishment is successful. For example: in the IPsec mode, the P-CSCF establishes a secure tunnel by determining the security parameters with the UE and distributing keys to the UE, so as to perform security processing on the data transmitted on the secure tunnel and enhance data security. Exchange security and reliability.

Step 309. UE sends user identification to S-CSCF through BS, ASN GW, PDG and P-CSCF to request user registration. After receiving UE's request, S-CSCF indicates to UE that user registration request has been received.

Step 310. The S-CSCF sends the received UE user ID to the HSS to request identity and authority verification. After the HSS completes the verification, it returns the verification result to the S-CSCF; the S-CSCF judges whether the received verification result is successful , if yes, execute step 311; otherwise, end the process of accessing the IMS domain.

Since the HSS stores the UE's identity legitimacy information and user authority information, in this step, the S-CSCF first sends the UE's user identity to the HSS for identity and authority verification; the HSS uses the received user identity and its own The stored identity legality information and user authority information are used to verify the UE, and after the verification is completed, the verification result of success or failure is returned to the S-CSCF.

Step 311. The S-CSCF indicates to the UE that the authentication has been passed, and the UE then interacts with the S-CSCF to establish a session connection between the UE and the IMS domain.

When the identity and authority verification is successful, the S-CSCF notifies the UE that the identity and authority verification has passed through the P-CSCF, PDG, ASN GW and BS; The CSCF requests the S-CSCF to establish a session connection between the UE and the IMS domain in order to carry the service data between the UE and the IMS domain; after receiving the request, the S-CSCF establishes the session connection, and after the establishment is successful , notify the UE through P-CSCF, PDG, ASNGW and BS.

So far, the process of the UE accessing the IMS domain through the WiMAX network in this embodiment is completed. Afterwards, using the session connection established above, the UE can enjoy the IMS domain service through the WiMAX network.

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

Claims (9)

1. A method for global microwave access interoperability WiMAX network access Internet Protocol Multimedia Subdomain IMS, characterized in that the address information of the packet data gateway PDG of the third generation 3G network is stored in advance in the domain name server DNS of the WiMAX network , the method includes the following steps: A. After the user equipment UE accesses the WiMAX network, it interacts with the DNS of the WiMAX network to obtain the address information of the packet data gateway PDG that provides the service; B. Through the WiMAX network and the PDG, the UE requests the Dynamic Address Assignment Protocol DHCP server to acquire the P-CSCF domain name in the IMS domain assigned to the UE, and sends the P-CSCF domain name to the 3G network DNS to obtain the address information of the P-CSCF entity; C. The UE requests registration from the serving call session control function S-CSCF entity in the IMS domain through the WiMAX network, the PDG, and the P-CSCF, and the S-CSCF notifies the UE to pass identity and authority verification. The UE requests the S-CSCF to establish a session connection between the UE and the IMS domain. 2. The method according to claim 1, wherein the method for the user equipment UE in step A to access the WiMAX network comprises: A11.UE is connected to the WiMAX network through the base station BS; A12. The UE obtains the local access Internet protocol IP address of the UE in the WiMAX network from the access gateway ASN GW through the BS, and uses the obtained IP address as the source address to route to the WiMAX network. 3. The method according to claim 2, wherein, between step A11 and step A12, the method further comprises: The authentication server AS performs access authentication on the UE, and judges whether the access authentication is successful, and if so, proceeds to step A12; otherwise, ends the process of accessing the IMS domain. 4. The method according to claim 3, wherein the method for the AS to perform access authentication on the UE is: UE first submits its own user identity to AS through BS and ASN GW, and AS obtains authentication set and user subscription information from home location server HSS, and according to the received user identity, authentication set and user subscription information, Perform access authentication on the UE to obtain an access authentication result; The method for judging whether the access authentication is successful is: If the access authentication result is successful, it is determined that the access authentication is successful; otherwise, it is determined that the access authentication fails. 5. The method according to claim 1, wherein the method for acquiring the address information of the PDG that provides the service in step A is: the UE communicates with the DNS of the WiMAX network through the base station BS and the access gateway ASNGW in the WiMAX network Interact to obtain the address information of the packet data gateway PDG that provides the service. 6. The method according to claim 5, wherein the method for obtaining the address information of the PDG providing the service comprises: A21.UE sends the domain name of PDG to DNS of WiMAX network through BS and ASN GW; A22. The DNS of the WiMAX network uses the received PDG domain name as an index, searches the corresponding relationship between the stored PDG domain name and PDG address information, determines the PDG address information corresponding to the PDG domain name, and passes the BS and ASN GW , returning the found PDG address information to the UE. 7. The method according to claim 6, characterized in that, after the step A22, the method further comprises: The UE establishes a secure tunnel between itself and the PDG according to the acquired address information of the PDG. 8. The method according to claim 1, wherein the address information of the PDG is: the IP address of the PDG. 9. The method according to claim 1, wherein the address information of the P-CSCF is: the IP address of the P-CSCF.

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