WO2007085154A1

WO2007085154A1 - A method and system for implementing isdn service in the packet network

Info

Publication number: WO2007085154A1
Application number: PCT/CN2006/002587
Authority: WO
Inventors: Lingzhi Mao; Shibi Huang; Youzhu Shi
Original assignee: Huawei Technologies Co. Ltd.
Priority date: 2006-01-24
Filing date: 2006-09-29
Publication date: 2007-08-02
Also published as: CN101009693B; CN101009693A

Abstract

A method and system for implementing ISDN service in the packet network, in the packet network based on the IMS architecture, adding an ISDN terminal equipment, and an ISDN user access gateway control function entity iAGF to which an ISDN terminal equipment accesses via S/T interface, and an ISDN user access gateway control function iAGCF which manages and controls the access of the accessed gateway functional entity and an ISDN application server iAS. The new process nodes iAS, iAGCF and iAGF are introduced by expanding the functions and interfaces of the original IMS system, and are overlapped in the IMS network, for accessing the ISDN user to IMS domain. The cooperation between iAS and iAGF can implement all kinds of basic services and supplementary services, thereby supporting the access of the ISDN users is inherited in IMS network. The ISDN services are achieved, and thereby accelerating the smoothing evolution from ISDN network to IMS network.

Description

Method and system for realizing integrated service digital network service in packet network This application claims to be submitted to the Chinese Patent Office on January 24, 2006, application number is 200610033392.7, and the invention name is "system for realizing integrated service digital network service in packet network. The priority of the Chinese Patent Application, the entire disclosure of which is incorporated herein by reference. Technical field

The present invention relates to the field of communication technologies, and in particular, to a method and system for implementing a service digital network service in a packet network. Background technique

The Interworking Protocol Multimedia Subsystem (IMS, IP Multimedia Subsystem) is a packet-based packet-based network. It is a subsystem that supports IP multimedia services proposed by Release 3 in Release 5, and uses the Session Initiation Protocol (SIP) protocol. It has the advantages of being independent of access and being able to flexibly provide multiple services. It is considered to be the only way to realize the convergence of mobile networks and fixed networks, the convergence of the Internet and communication networks, and the development of next generation networks (NG, Next Generation Network). Received industry attention. IMS is a multimedia control/call control platform in the Packet Switching (PS) domain. It supports both session and non-session multimedia services, providing a common service platform for future multimedia applications. Under the trend of network convergence, many international and domestic organizations are studying IMS-based network convergence solutions. The goal is to make IMS a common platform based on SIP sessions, while supporting existing mobile and fixed multiple access methods. As the research on network convergence has just begun, the technology is not mature enough, and its standardization work has become the focus of current research. In the framework of the next-generation network NGN, the terminal and the access network are various, and the core network based on the SIP session has only one IMS network, which serves both fixed and mobile terminals. Since the IMS network is a network with IP packet technology as the core, it is a fusion scheme of network evolution and a major trend in the future development. Therefore, you must consider how the ISDN emulation service is implemented under the IMS architecture.

At present, the research on IMS-based PSTN/ISDN emulation service is only limited to how to inherit PSTN service in IMS network, but there is no substantial progress and specific scheme for the inheritance of ISDN service. One can be found at the European Telecommunications Standards Institute ETSI (European The technical solution disclosed in the Telecommunications Standards Institute TISPA document "ETSI TS 02030 V<1.2.1>" is shown in Figure 1. The gray background part is defined as the IMS core network, which can realize the access of PSTN users. Simulation of some public service telephone network (PSTN) services. Since only the emulation service of the PSTN can be implemented without considering the access of the ISDN user, at the same time, from the architecture diagram itself, although described on the access side, the GW and the MG can access the ISDN user, but the interface PI to the network. (H.248 signaling) and H.248 signaling are used for media gateway control, but there is no way to transmit the information of Digital Subscriber Signalling No. 1 (DSS1, Digital Subscriber Signalling Nol) used by ISDN users, and the GM interface is a session initiation protocol. (SIP, Session Initiation Protocol) protocol interface, the ISDN user signaling information cannot be completely transmitted. Therefore, the scheme does not support the access of ISDN users in the framework. The scheme itself has no interface for transmitting ISDN signaling information, so it cannot be simulated. ISDN business. Summary of the invention

It is an object of the present invention to provide a method and system for implementing an Integrated Services Digital Network (ISDN) service in a packet network to implement an ISDN service based on the IMS network architecture.

According to the present invention, a method for implementing an integrated service digital network service in a packet network, where the packet network includes an Internet Protocol Multimedia Core Network Subsystem IMS, and at least one ISDN User Access Gateway function is set in the packet network. The entity iAGF, the ISDN user access gateway control function entity iAGCF, and the ISDN application server iAS, the method includes:

Performing DSS1 signaling between the ISDN terminal and the user access gateway control function entity iAGCF by using the iAGF;

The iAGCF implements the transmission of service control information between the ISDN terminal and the iAS and/or the IMS core network, thereby implementing ISDN emulation service control.

The method includes the following steps: the iAGCF receives the DSS1 signaling sent by the ISDN terminal device by using the iAGF, and the iAGCF sends the DSS1 signaling message to the serving call session control function. Entity S-CSCF;

The S-CSCF receives a message to perform a service triggering function, and triggers the message to the iAS; The iAS performs business logic control, and then sends subsequent information to the S-CSCF;

The S-CSCF performs a session routing function on the received message.

When the protocol handled by the S-CSCF is SIP-D or SIP-I, and the destination user of the message is a SIP URI user, the content of the DSS1 protocol or the ISUP protocol is discarded, and the SIP-D or SIP-I is translated into SIP, and continues to be Call routing; or,

The SIP-D or SIP-I message is transparently transmitted to the called end, and the network element in the called domain performs corresponding protocol conversion processing on the SIP-D or SIP-I.

The protocol conversion process specifically includes:

Translate it into SIP or DSS1 protocol, or translate between SIP-D and SIP-1 messages.

Preferably, when the protocol handled by the S-CSCF is SIP-D or SIP-I, and the message destination user is an E.164 user, the SIP-D or SIP-I message is routed backward, and the backward BGCF Or IBCF translates SIP-D or SIP-I into ISUP protocol, or

Perform mutual translation of SIP-D and SIP-I messages; or,

The transmission continues to the backward MGCF, which translates the SIP-D or SIP-I into the ISUP protocol.

The S-CSCF receives the call of the ISDN terminal device, and when the call is forwarded through the MGCF, if the service information in the incoming signaling cannot be completely mapped in the SIP protocol, the MGCF generates the SIP-1, or passes the Support ISUP protocol or DSS1 protocol to translate into SIP-D;

When the call is forwarded through the IBCF, if the service information in the incoming signaling cannot be completely mapped in the SIP protocol, the SIP-I is generated by the IBCF, or translated into SIP-D by supporting the ISUP protocol or the DSS1 protocol; or

Translating SIP-I into SIP-D by backward BGCF or MGCF;

When the call enters the S-CSCF through the I-CSCF, it triggers to the iAS.

Preferably, when the iAS processes the service logic, if the related service information that needs to be transmitted in the SIP message is still not fully mapped in the SIP protocol, the interface between the iAS and the S-CSCF is SIP-I, and the ISUP protocol is supported. Translation with the iAGCF of the DSS1 protocol.

The sending, by the iAGCF, the signaling message to the S-CSCF includes:

iAGCF translates the signaling and sends the translated signaling message to S-CSCF.

According to the present invention, a system for implementing an integrated service digital network service in a packet network, the packet network comprising an inter-network interconnection protocol multimedia subsystem IMS, the system comprising at least one ISDN user access gateway control function entity iAGF, The ISDN user access gateway control function entity iAGCF, and the ISDN application server iAS, the ISDN terminal accesses the network through the iAGF, where:

The iAGF is configured to complete the conversion between the information in the B path of the ISDN terminal and the media stream in the packet domain, and the transmission of the DSS1 signaling between the ISDN terminal and the user access gateway control function entity;

The iAGCF is configured to perform access management and control on the iAGF, and serve as an initial session protocol. The SIP user agent accesses the ISDN terminal device to the IMS network.

The iAS is connected to the serving call session control function entity S-CSCF, and interacts with the S-CSCF to provide an ISDN service control function according to the service trigger of the S-CSCF.

The iAGF is an access gateway, a relay gateway, a voice gateway access device, or an integrated access device, and the media gateway control protocol is an H.248 protocol.

The iAGCF supports translation between digital subscriber number one signaling and/or digital subscriber number one signaling DSS 1 and SIP.

The iAGCF supports encapsulation of DSS1 signaling information or/and signaling translation between DSS1 and ISUP in a SIP message, and

Translation between ISUP and SIP and/or encapsulation of ISUP in SIP.

The iAGCF supports translation between a SIP-I protocol encapsulating ISUP and a SIP-D protocol encapsulating DSS1 signaling information.

Preferably, the interface protocol between the iAGCF and the S-CSCF is a SIP protocol, and the SIP message is encapsulated with DSS1 signaling information or an ISUP SIP protocol, and the DSS1 signaling information is a DSS1 network layer message and part. DSS1 network layer message or DSS1 information element.

Preferably, the encapsulation of the DSS1 signaling information is implemented by rendering a encapsulation type as a DSS1 message or a DSS1 information element in a newly extended media type of a Session Initiation Protocol SIP message body. Preferably, the S-CSCF in the Internet Protocol Multimedia Subsystem IMS supports a SIP protocol encapsulating DSS1 signaling information and/or a SIP protocol encapsulating ISUP.

Preferably, the interface between the iAS and the S-CSCF supports a SIP protocol, a SIP protocol SIP-D encapsulated with DSS1 signaling information, and a SIP protocol SIP-L encapsulated with ISUP. Preferably, the iAS supports Translation between the SIP-D protocol and the SIP-I protocol. The present invention is based on an IMS-based packet network for implementing an Integrated Services Digital Network (ISDN) service and a method for implementing an integrated service digital network service in an Internet Protocol Multimedia Core Network Subsystem (IMS).

In the packet network based on the IMS architecture, the new processing nodes iAS, iAGCF and iAGF are introduced and superimposed on the IMS network to connect the ISDN users to the IMS domain. The cooperation between the iAS and the iAGCF can implement various basic services of the ISDN. And supplementing the service, thereby inheriting the access of the ISDN user in the IMS network, and realizing the purpose of the ISDN service, can promote the smoothing of the ISDN network to the evolution of the IMS network, and effectively protect the operator investment.

DRAWINGS

1 is a PES-based IMS network architecture diagram in the prior art;

2 is a system architecture diagram of an exemplary integrated services digital network service in accordance with the present invention;

3 is a schematic diagram of a system architecture for implementing an integrated services digital network service in an embodiment of the present invention;

4 is a flowchart of implementing an ISDN basic call in an embodiment of the present invention;

Figure 5 is a flow diagram of implementing ISDN supplementary service terminal mobility in accordance with the present invention; Figure 6 is a flow diagram of user-user signaling 1 for implementing ISDN supplementary services in accordance with the present invention. detailed description

The present invention will be described in detail below with reference to the drawings and specific embodiments.

Referring to FIG. 2, a specific embodiment of the present invention is described. In the schematic diagram of the network system based on the IP Multimedia Subsystem (IMS) architecture shown in FIG. 2, in addition to the ISDN terminal device 201 (ISDN TE), ISDN User access gateway function entity (iAGF, iSDN user access gateway function) 202, ISDN user access gateway control function (IAGCF, ISDN User Access Gateway Control Function) 203, ISD Application Server (iAS, ISDN Application Server) 204, four network entities and their interfaces, other network entities and related interfaces and the European Telecommunications Standards Institute (ETSI) The IMS-related definitions in TISPAN are the same.

Referring to Figure 2, the four network entities ISDNTE, iAGCF, iAGF, and iAS are briefly described:

I. Integrated service data network terminal equipment ISDN TE

ISDN TE is an ISDN terminal, which is an entity that uses ISDN services. Its role is to connect with the iAGF through the standard S/T reference point defined in the ISDN network. For the definition of the S/T reference point, see the S standard of the ISDN. The /T interface is connected to the iAGF function.

Second, ISDN user access gateway function iAGF

The iAGF is an access device located between the circuit domain and the packet domain, and is configured to provide a physical access function of the ISDN user, complete the conversion function between the information in the ISDN terminal B path and the IP media stream in the packet domain; The ISDN terminal D path information accesses the ISDN access gateway control function entity.

Third, ISDN user access gateway control function iAGCF

The iAGCF provides the access control function of the user. The media gateway control function is implemented by the media gateway control protocol H.248 protocol and the iAGF. The iAGCF is connected to the iAGF through the IUA protocol to complete the transmission of the DSS1 signaling. The iAGCF has the SIP UA function. The ISDN user accesses the IMS network. The functions provided by the iAGCF include:

1) The interface between the iAGCF and the Call Session Control Function (CSCF): II uses the SIP protocol or the SIP protocol SIP-D that encapsulates the DSS1 message or encapsulates the ISDN user part (ISUP, ISDN User). Part) SIP protocol SIP-I.

The SIP-1 protocol is an existing standard protocol and is described in detail in ITU-T Q.1912.5 and IETF RFC3204.

2) DSS1 protocol and SIP protocol signaling translation function:

In DSS1, SIP

When the ISDN supplementary service information cannot be completely mapped in the SIP protocol, the DSS1 network layer may be encapsulated in the SIP message body. The message or DSS1 information unit, called the extended SIP protocol is SIP-D. In this way, the ISDN service simulation control function is transmitted with the DSS1 information between the iAGCF and the ISDN TE, and the ISDN emulation service is realized. SIP-D is a function extension of the SIP protocol, and its extension method is:

The DSS1 network layer message/DSS1 information element is encapsulated in the SIP message body. For this type of SIP message body, a new media type (Media Type) is defined to implement the definition format example as follows:

a) The media type used to deliver DSS1 Layer 3 messages:

Media type name: application

Media subtype name: DSSl -Message

Required parameters: Version

Optional parameters: base

Encoding scheme: code-type

b) . The type of media used to pass the DSSl Layer 3 information element:

Media type name: application

Media subtype name: DSSl -IE

Required parameters: Version

Optional parameters: base

Encoding scheme: code-type

The parameter "version" indicates a DSS1 message issued by different organizations, such as ITU-T, ETSI, ANSI, etc., and the parameter "base" indicates a protocol version number that defines a DSS1 message, such as a definition message such as Q.931/Q.932; The code-type is a code format for the DSS1 message or information element encapsulation format, which may be a binary mode, that is, encapsulating a DSS1 network layer message or information element, or a text encapsulation manner, that is, describing a DSS1 network layer message or a message unit containing information in a text manner. Order information.

The DSS1 message means that the format of the Q.931 message definition includes at least the message name and the message body part.

3) The signaling translation function of the DSS1 protocol and the SIP-1 protocol:

That is, iAGCF does not directly translate the DSS1 protocol and the SIP protocol, but indirectly through the translation of the DSS1 protocol and the ISUP protocol, and the translation of the ISUP protocol and the SIP protocol. Now the translation of the DSS1 protocol and the SIP protocol, when the service information carried in the ISUP protocol cannot be mapped in the SIP protocol, the iAGCF will generate the SIP-I.

4) Providing a media gateway control function to complete control operations such as establishing, maintaining, and clearing the iAGF media stream connection;

To simplify the interaction process, the IMS MRFC does not provide media resource control for the iAGF access user. The iAGCF can also provide media resource control functions for the iAGF access user, and provide media resources through H.248, SIP protocol or custom internal protocols. (such as signal tone, etc.) control; IV, ISDN application server iAS

The iAS provides logical control functions for ISDN service emulation for ISDN terminal users accessing the packet core network. The iAS can be an independent ISDN service emulation service logic control entity, or it can superimpose the ISDN emulation service control function based on the original IMS AS. The functions provided by the iAS include: 1) Interface between the AS and the Serving-Call Session Control Function (S-CSCF): The ISC' reference point is based on the SIP protocol, in some cases SIP-D (ie, the SIP protocol encapsulating the DSS1 message, the information element), in some cases the SIP-1 protocol;

2) iAS has ISDN emulation business logic control capabilities:

3) iAS has the translation capabilities of SIP-D and SIP-I:

After the iAS has processed the service control, if the related service information that needs to be transmitted in the SIP message still cannot be fully mapped in the SIP protocol, the iAS can generate the SIP-D or the SIP-I. 5. Interface/reference point Expansion

The node service CSCF (S-CSCF), the query CSCF (I-CSCF, Interrogating CSCF), the media gateway control function (MGCF, Media Gateway Control Function), and the egress gateway control function entity (BGCF, Breakout Gateway Control) included in the IMS core network Function), Interconnection Border Control Function (IBCF), based on the definition of ETSI TISPAN standard, supports SIP-I and/or SIP-D protocol. Other network entities and related interfaces in Figure 2 are completely and ETSI TISPAN. The standard definition is the same.

In the logical CSCF of the IMS system, a new logical interface/reference point II, ISC' is extended. Through the introduction of these two types of interfaces/reference points, ISDN session control and service control node connection are realized. Into the IMS system, so as to implement ISDN emulation service in the IMS system, these two types of interfaces / reference points are as follows:

The functions of the A and II interfaces include:

The II interface supports the SIP user agent node to connect with the SCSCF;

The II interface supports the standard SIP protocol, and supports SIP protocols that carry DSS1 signaling information, and/or SIP protocols that carry ISUP.

B, ISC' interface features include:

The ISC is used for connecting the service control node with the SCSCF;

The ISC interface supports the standard SIP protocol, and supports the SIP protocol carrying DSS1 signaling information, and/or the SIP protocol carrying ISUP.

The SIP protocol carrying the DSS1 signaling information, as described in the foregoing A and B, wherein the SIP message may encapsulate the DSS1 network layer message in the SIP message body, or may encapsulate the DSS1 network layer information element in the SIP message body. As described in the foregoing A and B, the SIP protocol supporting the ISUP information is supported, and the ISUP or ISUP information element is encapsulated in the message body of the SIP message.

The present invention implements ISDN service control by introducing network nodes iAGCF and iAS, and accesses ISD users to the IMS domain through the iAGF access device, thereby providing ISDN services.

The following describes how to implement ISDN emulation services in an IMS system by comparing common examples. It should be particularly noted that the flowcharts and captions presented in Figures 3, 4, or 5 are merely illustrative of the key techniques of the present invention and do not represent a complete call and service control flow.

In the architecture shown in Figure 2, the iAGCF accesses the signaling process of the incoming and outgoing calls of the user, which is briefly described as follows:

Situation 1 :

The ISDN TE initiates the call as the calling party. The ISDN service information cannot be completely mapped in the SIP protocol. The interface between the iAGCF and the S/I-CSCF is SIP-D or SEP-1 (the iAGCF supports the DSS1 protocol and ISUP). The translation of the protocol directly generates SEP-1); the outgoing signaling reaches the S-CSCF and is triggered to the iAS. After the iAS processes the service logic, the message needs to be routed back to the S-CSCF for subsequent processing according to the IMS service processing flow. If the iAS needs to be The related service information transmitted in the SIP message still cannot be fully mapped in the SIP protocol. The interface protocol between the service information iAS and the S-CSCF needs to be encapsulated with DSS1 signaling information. The SIP protocol SIP-D, or the SIP protocol SIP-I encapsulating ISUP, after the S-CSCF receives the message from the iAS:

Situation 1-1

If the protocol processed by the S-CSCF is a SIP protocol SIP-D encapsulating DSS1 signaling information or a SIP protocol SIP-I encapsulating ISUP, and the called party is a SIP UI user, the content of the DSS 1 protocol or the ISUP protocol is discarded. Translate SIP-D or SIP-I into SIP and continue to route to the called party; or transparently transmit SIP-D or SIP-I messages to the called route, and SIP-D from a certain network element in the called domain Or SIP-I processing, translate it into other suitable protocols such as SIP or DSS1, or perform mutual translation of SIP-D and SIP-I messages;

Situation 1-2

If the protocol handled by the S-CSCF is SIP-D or SIP-I, and the called party is an E.164 user, the SIP-D or SIP-I message is routed backward, and the backward BGCF or IBCF will SIP- D or SIP-I is translated into other suitable protocols such as ISUP, or the mutual translation of SIP-D and SIP-I messages is completed, or the transmission is continued; or the backward MGCF translates SIP-D or SIP-I into Other suitable protocol scenarios such as ISUP 2;

The called party is ISDN TE, according to the incoming call status of the calling user:

Situation 2-1

If the incoming call is forwarded through the MGCF, if the service information in the incoming signaling cannot be completely mapped in the SIP protocol, the MGCF may generate the SIP-I, or directly generate the SIP by supporting the translation of the ISUP protocol and the DSS1 protocol. -D;

Situation 2-2

If the incoming call passes through the IBCF, if the service information in the incoming signaling cannot be fully mapped in the SIP protocol, the IBCF can generate the SIP-I, or directly generate the SIP by supporting the translation of the ISUP protocol and the DSS1 protocol. -D, it is also possible not to generate SIP-D by IBCF, but translate SIP-I into SIP-D by backward BGCF or MGCF;

After that, the incoming call enters the S-CSCF through the I-CSCF and is triggered to the iAS. After the iAS processes the service logic, if the related service information that needs to be transmitted in the SIP message is still not fully mapped in the SIP protocol, iAS to S- The interface between the CSCFs can be SIP-D or SIP-I. If it is SIP-1, the S-CSCF can translate SIP-I into SIP-D. S-CSCF translation; If the incoming signaling received by the iAGCF is SIP-I, the iAGCF supports translation of the ISUP protocol and the DSS1 protocol.

Referring to FIG. 3, a system for implementing an integrated service digital network service in a packet network according to the present invention, the packet network includes an inter-network interconnection protocol multimedia subsystem IMS, and the system includes an ISDN user access gateway functional entity. The iAGF 202, the ISD user access gateway control function entity iAGCF 203, and the ISDN application server iAS 204, the ISDN terminal 201 accesses the network through the iAGF 202, where:

The iAGF202 is configured to complete the conversion between the information in the B-path of the ISDN terminal and the inter-network interconnection protocol media stream in the packet domain, and perform the transmission of the DSS1 signaling between the ISDN terminal and the user access gateway control function entity;

The iAGCF 203 is configured to perform access management and control on the access gateway function entity, and use the ISDN terminal device to access the IMS network as the initial session protocol.

The iAS 204 is coupled to the I/S-CSCF 205 for providing service control functions for accessing the ISDN terminal 201.

The iAGF 202 may use an access gateway, a relay gateway, a voice gateway access device, or an integrated access device according to a specific situation, and the media gateway control protocol is an H.248 protocol.

The iAGCF 203 supports translation between digital subscriber number one signaling and/or digital subscriber number one signaling DSS1 and SIP, encapsulation of DSS1 signaling information in SIP messages or/and signaling translation between DSS1 and ISUP, and

Translation between ISUP and SIP and/or encapsulation of ISUP in SIP.

The IAGCF 203 supports translation between the SIP-I protocol encapsulating ISUP and the SIP-D protocol encapsulating DSS1 signaling information.

The interface protocol between the iAGCF 203 and the call session control function entity CSCF is a SIP protocol, and the SIP message is encapsulated with DSS1 signaling information or an ISUP SIP protocol, and the DSS1 signaling information is a DSS1 network layer message and a part of the DSS1. Network layer message or DSS1 information element.

In an embodiment of the present invention, the encapsulation of the DSS1 signaling information is implemented by rendering the encapsulation type as a DSS1 message or a DSS1 information element in a newly extended media type of the Session Initiation Protocol SIP message body. The Serving Call Session Control Function Entity S-CSCF in the Internet Protocol Multimedia Subsystem IMS supports the SIP protocol encapsulating SS1 signaling information and/or supports the SIP protocol encapsulating ISUP.

The interface between the ISDN application server 204 and the session control function entity I/S-CSCF in the system supports the SIP protocol, the SIP protocol SIP-D encapsulating the DSS 1 signaling information, and the SIP protocol SIP-I encapsulating the ISUP.

In addition, iAS 204 supports translation between the SIP-D protocol and the SIP-1 protocol. The following describes an example of how to implement ISDN emulation service in an IMS system. The flowcharts and text descriptions provided are merely illustrative of the key technologies of the present invention, and do not represent a complete call and service control process, nor Exhaust all possible branching processes.

Figure 4 shows the ISDN basic service simulation process through the II and ISC interfaces under the control of iAGCF and iAS. The program steps indicated by the various arrow arrows are described as follows:

1. The ISDN terminal A sends a DSS 1 SETUP message through the S/T interface, requesting to establish a voice call;

2. The iAGF transparently transmits the SETUP message to the iAGCF through the IUA link.

3. After receiving the DSS1 SETUP message, the iAGCF responds with the CALL PROCEEDING message, and performs the signaling translation function and the media gateway function; this message is sent to the iAGF through the IUA link.

4, iAGF transparent transmission CALL PROCEEDING message to the calling ISDN terminal

5. The iAGCF performs a signaling translation function, and translates the DSS1 SETUP message into a SIP INVITE message, and sends the message to the SCSCF through the II interface.

6. The SCSCF performs a service triggering function, and triggers a SIP INVITE message to the iAS.

7. The iAS performs the ISDN voice call service control logic, and routes the SIP INVITE message to the SCSCF according to the IMS session flow;

8. The SCSCF performs a session routing function, and sends a SIP INVITE message to the destination SIP UE.

9. The remote user responds with 180 Ringing. The SIP message is omitted from the trigger to the iAS, and the iAS routes the message to the SCSCF process (the subsequent signaling process also omits this process);

10. The SCSCF sends the SIP 180 Ringing to the iAGCF through the II interface.

11, 12, iAGCF translates the SIP 180 RINGING message into an alerting message, and sends it to the ISDN terminal through the iAGF; 13. The destination SIP UE sends a 200 OK SIP message to answer the call;

14. The SCSCF sends the 200 OK message to the iAGCF through the ISC interface.

15, 16, iAGCF performs signaling translation function, and translates to DSS1 CONNECT to the ISDN terminal through iAGF;

17, 18, the ISDN terminal responds with a CONNECT ACKNOWLEDGE message, and the message is sent to the iAGCF through the iAGF;

19. The iAGCF translates to an ACK message and sends it to the SCSCF.

20. The SCSCF routes the ACK message to the destination SIP terminal, and the session is established;

21, 22, the ISDN terminal sends a DISCONNECT message to tear down the call, and the message is sent to the iAGCF through the iAGF;

23, iAGCF translation DSS1 DISCONNECT message is sent to the S-CSCF SIP BYE message;

24. The SCSCF routes the message to the destination SIP terminal to dry the session;

25, 26, iAGCF sends a RELEASE message to release the call according to DSS1 signaling requirements, and the message is sent to the ISDN terminal through the iAGF;

27, 28, ISDN terminal sends RELEASE COMPLETE this message is sent to iAGCF through iAGF, the call is released;

29, 30, the remote user uses the 200 OK message corresponding to the BYE request of the iAGCF; It can be seen from the above example that the simulation control of the ISDN basic service is completed through the introduction of iAGCF and iAS, and the following example will give specific implementation of the ISDN supplementary service. For example, take the ISDN terminal mobility (abbreviated as TP) service as an example:

FIG. 5 is a diagram showing an example of implementing supplementary services under the control of an interface between an iAS and an iAGCF introduced by the present invention through II, ISC, and an interface. The served user is an ISDN user, and the remote user is a PSTN/ISDN user, and the IMS is processed by the MGCF. The domain is connected to the CS domain. You can establish a session according to the previous implementation example. The description is not repeated here. The process is as follows:

1. The ISDN terminal sends a suspend (SUSPEND) message to the iAGF through the S/T interface, requesting a TP (terminal mobile) service suspension (SUSPEND) operation;

2. The iAGF transparently transmits the message to the iAGCF through the IUA link.

3. iAGCF performs DSS 1 signaling to SIP signaling translation function, and this SUSPEND is eliminated. The information is encapsulated in the SIP INFO message and sent to the SCSCF through the II interface;

4. The SCSCF completes the service triggering function, and routes the INFO message to the iAS through the ISC interface.

5. The iAS analyzes the SIP message content, performs the ISDN TP service control logic, and returns a DSS1 SUSPEND ACKNOWLEDGE message, which is encapsulated in the 200 OK message and sent to the SCSCF through the ISC' interface;

6. The SCSCF completes the session routing function and routes the message to the served user iAGCF.

7. The serviced user iAGCF performs the signaling translation function, extracts the SIP 200 OK message body content (SUSPEND ACKNOWLEDGE message), and sends the SUSPEND ACKNOWLEDGE message to the iAGF through the IUA link;

8. The iAGF transparently transmits the message to the ISDN device terminal of the served user;

9. The iAS performs business logic control, and sends an 81? 1>^0 message encapsulated with 181^8118 to the MGCF. Optional operation:

The iAS sends the SIP message encapsulating the DSS1 SUSPEND to the MGCF. The MGCF maps the ISUP SUS message to the remote user according to the DSS1 SUSPEND message in the message body.

In step 4, the SCSCF completes the SIP message encapsulating the DSS1 SUSPEND and converts it into a SIP-I message encapsulating the ISUP. In this case, the iAS does not need to perform this conversion.

10. MGCF responds to iAS using SIP 200 OK;

11. The MGCF sends a SUS message to the remote user of the PSTN/ISDN;

12. The iAS sends a SIP UPDATE message to the iAGCF through the SCSCF, and the SDP description is modified to receive only ( received only );

13. The SCSCF routes the message to the calling iAGCF, and the calling iAGCF controls the media connection mode of the iAGF to be received only through the H.248 protocol control;

14. The SCSCF responds to the SCSCF with 200 OK;

15. The calling iAGCF responds to the iAS with 200 OK, completing the Suspend operation in the ISDN TP;

Through the above steps, the call suspension operation of the ISDNTP service is implemented, and the same process can be used to complete the call recovery operation of the TP service, thereby completing the terminal mobility service.

Referring to FIG. 6, the ISDN User-User Signaling 1 (UUS1) service is taken as an example to illustrate when II, The implementation of the ISDN service when the ISC' interface is SIP-I is as follows:

1) The ISDN terminal A sends a DSS1 SETUP message with the UUS1 information element in the message (the process of transmitting the message to the iAGCF through the iAGF is omitted in the figure);

2) After receiving the message, the iAGCF translates the DSS1 SETU message into an ISUP IAM message, and translates the DSS1 UUS1 information element containing the service information into an ISUP ATP information unit, and the translated ISUP IAM message is encapsulated in the SIP message body. Thus translated into a SIP-1 INVITE message;

3) The SCSCF receives the SIP-I INVITE message and performs a service triggering function to trigger the message to the iAS for service processing.

4) The iAS receives the SIP-I INVITE message, and the iAS performs business logic control, and sends the message to the SCSCF for subsequent routing according to the IMS message routing rule;

5) The SIP-I INVITE message is routed to the called side SCSCF, (the intermediate nodes such as I-CSCF may be omitted in the figure);

6) The called S-CSCF routes the SIP-I INVITE message to the called iAGCF called iAGCF to perform the signaling translation function, and extracts the ISUP encapsulated in the SIP-I message body into a DSS1 SETUP message, so that the called user is a SIP user. Before the S-CSCF sends the SIP message to the P-CSCF, the S-CSCF may delete the ISUP IAM message in the SIP message body to change the SIP-I message into a SIP message, or directly send it through the P-CSCF. Give the called SIP terminal;

7) The called iAGCF node sends the translated SETUP message (with UUS1 service information) to the called ISDN terminal through the iAGF, at which point the UUS1 service has been completed.

The foregoing is illustrative of the principles of the invention. It will be understood that the specific embodiments of the present invention are not limited thereto. Various changes and modifications may be made without departing from the spirit and scope of the invention.

Claims

Rights request

A method for implementing an integrated service digital network service in a packet network, the packet network comprising an internet protocol multimedia core network subsystem MS, wherein at least one ISDN user access gateway functional entity is set in the packet network The iAGF, the ISDN user access gateway control function entity iAGCF, and the ISDN application server iAS include:

The iAGCF implements service control information transmission between the ISDN terminal and the iAS and/or the IMS core network, thereby implementing ISDN service control.

2. The method according to claim 1, wherein the method comprises the steps of: connecting an ISDN terminal to an IMS network, as follows:

The iAGCF receives the DSS1 signaling message sent by the ISDN terminal device through the iAGF; the iAGCF sends the DSS1 signaling message to the serving call session control function entity S-CSCF;

The S-CSCF receives a message to perform a service triggering function, and triggers the message to the iAS;

The iAS performs business logic control, and then sends subsequent information to the S-CSCF;

The S-CSCF performs a session routing function on the received message.

3. The method of claim 2, wherein

The SIP-D or SIP-I message is transparently transmitted to the called end, and the network element in the called domain performs corresponding protocol conversion processing on the SIP-D or SIP-1.

4. The method according to claim 3, wherein the protocol conversion processing comprises:

Translate it into SIP or DSS1 protocol, or translate between SIP-D and SIP-I messages.

5. The method of claim 2, wherein

When the protocol handled by the S-CSCF is SIP-D or SIP-I, and the message destination user is an E.164 user, the SIP-D or SIP-I message is routed backward, and the backward BGCF or IBCF will SIP. -D or SIP-I translates to ISUP protocol, or Perform mutual translation of SIP-D and SIP-I messages; or, .

The transmission continues to the backward MGCF, which translates SIP-D or SIP-I into the ISUP protocol.

The method according to claim 2, wherein the S-CSCF receives a call from the ISDN terminal device,

When the call is forwarded through the MGCF, if the service information in the incoming signaling cannot be completely mapped in the SIP protocol, the MGCF generates the SIP-I, or translates into the SIP-D by supporting the ISUP protocol or the DSS1 protocol;

When the call is forwarded through the IBCF, if the service information in the incoming signaling cannot be completely mapped in the SIP protocol, the SIP-I is generated by the IBCF, or translated into SIP-D by supporting the ISU protocol or the DSS1 protocol; or

Translating SIP-I into SIP-D by backward BGCF or MGCF;

When the call enters the S-CSCF through the I-CSCF, it triggers to the iAS.

7. The method of claim 2, wherein

When the iAS processes the service logic, if the related service information that needs to be transmitted in the SIP message is still not fully mapped in the SIP protocol, the interface between the iAS and the S-CSCF is SIP-I, and the ISUP protocol and the DSS1 protocol are supported. iAGCF is translated.

The method according to claim 2, wherein the sending, by the iAGCF, the signaling message to the S-CSCF includes:

The iAGCF translates the signaling and sends the translated signaling message to the S-CSCF.

A system for implementing an integrated service digital network service in a packet network, the packet network comprising an inter-network interconnection protocol multimedia subsystem IMS, wherein the system comprises at least one ISDN user access gateway control function entity iAGF The ISDN user access gateway control function entity iAGCF, and the ISDN application server iAS, the ISDN terminal accesses the network through the iAGF, where:

The iAS is connected to the serving call session control function entity S-CSCF, and The S-CSCF performs an interaction, and is configured to provide an ISDN service control function according to the service trigger of the S-CSCF.

The system according to claim 9, wherein the iAGF is an access gateway, a relay gateway, a voice gateway access device or an integrated access device, and the media gateway control protocol is an H.248 protocol.

11. The system according to claim 9, wherein the iAGCF supports translation between digital subscriber number one signaling and/or digital subscriber number one signaling DSS1 and SIP.

12. The system according to claim 9, wherein the iAGCF supports encapsulation of DSS1 signaling information or/and signaling translation between DSS1 and ISUP in a SIP message, and

Translation between ISUP and SIP and/or encapsulation of ISUP in SIP.

13. The system according to claim 9, wherein the iAGCF supports translation between a SIP-I protocol encapsulating ISUP and a SIP-D protocol encapsulating DSS1 signaling information.

The system according to any one of claims 11 to 13, wherein the interface protocol between the iAGCF and the S-CSCF is a SIP protocol, and the SIP message is encapsulated with DSS1 signaling information or ISUP. The SIP protocol, the DSS1 signaling information is a DSS1 network layer message, a partial DSS1 network layer message or a DSS1 information element.

The system according to claim 14, wherein the encapsulation of the DSS1 signaling information is by using a newly extended media type of a session initiation protocol SIP message body to describe a encapsulation type as a DSS1 message or a DSS1 information element. To achieve.

The system according to claim 9, wherein the S-CSCF in the Internet Protocol Multimedia Subsystem IMS supports a SIP protocol encapsulating DSS1 signaling information and/or a SIP protocol supporting ISUP.

The system according to claim 9, wherein the interface between the iAS and the S-CSCF supports a SIP protocol, a SIP protocol SIP-D encapsulating DSS1 signaling information, and a SIP encapsulated with an ISUP. Protocol SIP-I.

18. The system of claim 17, wherein the iAS supports translation between the SIP-D protocol and the SIP-I protocol.