CN104796384B

CN104796384B - Call processing method, device and system

Info

Publication number: CN104796384B
Application number: CN201410025978.3A
Authority: CN
Inventors: 杨强; 王忱
Original assignee: Nanjing ZTE New Software Co Ltd
Current assignee: Nanjing ZTE New Software Co Ltd
Priority date: 2014-01-20
Filing date: 2014-01-20
Publication date: 2020-09-29
Anticipated expiration: 2034-01-20
Also published as: RU2016134423A; RU2654147C2; WO2015106558A1; CN104796384A; RU2016134423A3

Abstract

The invention discloses a call processing method, a device and a system, wherein the method comprises the following steps: adopting an access switching control function (ATCF) to judge whether one or more network elements for realizing media management between the ATCF and a continuity application server (SCC AS) support the use of media resources created for a switched call for the switched call; based at least on the determination of "yes" at the ATCF, the anchor media creates a call and/or the anchor media handoff call. The invention solves the problem that the switching of the anchoring media determined by the ATCF in the related technology does not play a corresponding role, thereby enabling the ATCF to better determine the mode of adopting the anchoring media under the certain conditions.

Description

Call processing method, device and system

Technical Field

The present invention relates to the field of communications, and in particular, to a method, an apparatus, and a system for call processing.

Background

An IP Multimedia Subsystem (IMS) is an IP-based Network architecture proposed by the third Generation Partnership Project (3 rd Generation Partnership Project, 3 GPP) organization, which constructs an open and flexible service environment, supports Multimedia applications, and provides rich Multimedia services to users.

Currently, Mobile communication is mainly Circuit Switched (CS) network, such as Global System for Mobile Communications (GSM) and Code Division Multiple Access (CDMA). In the specifications of TS24.292, 3GPP TS23.237, and 3GPP TS24.237, there are already descriptions of signaling and procedures for implementing handover between Packet Switch (PS) and CS by using Access Transfer Control Function (ATCF), for example, Enhanced Single Radio Voice Call (eSRVCC) technology.

However, there are problems in the related art: the eSRVCC technology is used for performing anchoring media switching, a roaming user is switched, if one or more network elements are located between an Access Transfer Control Function (ATCF) of a visited domain of a user and a home domain of the user to implement media management, for example, an Interconnection Border Control Function (IBCF), the anchoring media switching is performed according to a related technology, which cannot accelerate the media switching speed. The inventors found that this is due, among other reasons: although the ATCF employs the anchor media handover, since a new call is created in the IBCF, a new media resource is created, and the media of the handover call invite message received by the continuity application server (SCC AS for short) is different from the media of the call to be handed over, a media negotiation will be performed with the remote end, and the remote media of the Access handover GateWay (ATGW for short) will be modified by the negotiation result, and a normal call can be realized after the flow is finished.

Therefore, in the related art, the ATCF determines that the anchor media handover employed does not play a corresponding role.

Disclosure of Invention

The invention provides a call processing method, a call processing device and a call processing system, which at least solve the problem that the anchoring media switching determined by ATCF in the related technology does not play a corresponding role.

According to an aspect of the present invention, there is provided a call processing method, including: an access switching control function (ATCF) judges whether one or more network elements for realizing media management between the ATCF and a continuity application server (SCC AS) support the use of media resources created for a switched call for the switched call; and the ATCF establishes a call and/or an anchor media switching call according to the judgment result of yes at least.

Preferably, the ATCF receives a message from the one or more network elements, where the message carries information on whether the network element implements media management, and information on whether a media resource created for a switched call can be used for the switched call.

Preferably, the ATCF receiving the message from the one or more network elements comprises: the ATCF sends the received registration request message and/or call request message to the one or more network elements; and the ATCF receives a registration response message and/or a call response message from the one or more network elements, where the registration response message and/or the call response message carries information on whether the network element implements media management, and information on whether media resources created for the switched call can be used for the switched call.

Preferably, the determining, by the ATCF, whether the one or more network elements each support a media resource to be created for the handed over call includes: after sending the registration request message to the one or more network elements, the ATCF receives a registration response message from the one or more network elements; and the ATCF carries out the judgment according to the routing information carried in the registration response message and/or the ATCF local policy.

Preferably, the ATCF routes the handover call to the one or more network elements; and the one or more network elements hand over the media resource of the switched call to the switched call according to the identifier of the switched call.

Preferably, the handing over of the media resources of the handed over call to the handed over call by the one or more network elements comprises: the one or more network elements hand over a portion of the media resources of the handed over call to the handed over call; the media resources not handed over are reserved for the original call.

Preferably, the ATCF does not perform the anchor media creation call and/or does not perform the anchor media handover call if the determination result is negative.

According to another aspect of the present invention, there is also provided a call processing apparatus, in an access handover control function ATCF, the apparatus comprising: a judging module, configured to judge whether all one or more network elements that implement media management between the ATCF and a continuity application server SCC AS support that a media resource created for a switched call is used for a switched call; and the processing module is used for establishing a call by the anchoring media and/or switching the call by the anchoring media at least according to the judgment result of yes.

Preferably, the method further comprises the following steps: a receiving module, configured to receive a message from the one or more network elements, where the message carries information on whether the network element implements media management, and information on whether a media resource created for a switched call can be used for the switched call.

Preferably, the receiving module includes: a sending unit, configured to send the received registration request message and/or call request message to the one or more network elements; a first receiving unit, configured to receive a registration response message and/or a call response message from the one or more network elements, where the registration response message and/or the call response message carries information on whether the network element implements media management, and information on whether a media resource created for a switched call can be used for the switched call.

Preferably, the processing module comprises: a second receiving unit, configured to receive a registration response message from the one or more network elements after sending the registration request message to the one or more network elements; and the judging unit is used for judging according to the routing information and/or the ATCF local policy carried in the registration response message.

Preferably, the processing module is further configured to not perform an anchor media creation call and/or not perform an anchor media handover call if the determination result is negative.

According to another aspect of the present invention, there is also provided a call processing system, including the apparatus, wherein the apparatus further includes: a routing module for routing the handover call to the one or more network elements; the system further comprises: and the one or more network elements are used for handing over the media resources of the switched call to the switched call according to the identifier of the switched call.

Preferably, the one or more network elements are configured to hand over a portion of the media resources of the handed over call to the handed over call; the media resources not handed over are reserved for the original call.

According to the invention, an access switching control function (ATCF) is adopted to judge whether one or more network elements for realizing media management between the ATCF and a continuity application server (SCC AS) support media resources to be created for a switched call to be used for switching the call; based at least on the determination of "yes" at the ATCF, the anchor media creates a call and/or the anchor media handoff call. The problem that the switching of the anchoring media determined by the ATCF in the related technology does not play a corresponding role is solved, so that the ATCF can better determine the mode of adopting the anchoring media under the certain conditions.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

FIG. 1 is a flow chart of a call processing method according to an embodiment of the present invention;

fig. 2 is a block diagram of a call processing apparatus according to an embodiment of the present invention;

FIG. 3 is a block diagram of a preferred architecture of a call processing device according to an embodiment of the present invention;

FIG. 4 is a block diagram of a preferred architecture of a call processing device according to an embodiment of the present invention;

FIG. 5 is a block diagram of a preferred architecture of a call processing device according to an embodiment of the present invention;

FIG. 6 is a block diagram of a call processing system according to an embodiment of the present invention;

FIG. 7 is a flow chart for use in handing over a call by the "media resources" that the ATCF knows in the registration flow whether the subsequent call passes through the IBCF and whether both the passed IBCF support the handed over call, according to an embodiment of the present invention;

fig. 8 is a first flowchart of the ATCF access subscriber determining to establish a PS call in an anchor media manner as a caller according to an embodiment of the present invention;

fig. 9 is a flowchart of determining to create a PS call in an anchor media manner when an ATCF access user is called according to an embodiment of the present invention;

fig. 10 is a flowchart ii of the ATCF access subscriber determining to establish a PS call in an anchor media manner as a caller according to the embodiment of the present invention;

fig. 11 is a call flow diagram for implementing a handover from PS access to CS access using ATCF in accordance with an embodiment of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

In this embodiment, a call processing method is provided, and fig. 1 is a flowchart of the call processing method according to the embodiment of the present invention, as shown in fig. 1, the flowchart includes the following steps:

step S102, an access handover control function ATCF determines whether all one or more network elements (for example, IBCF, hereinafter described using IBCF AS an example) between the ATCF and a continuity application server SCC AS that implement media management support a media resource to be created for a handed over call;

step S104, the ATCF establishes call and/or anchor media switching call according to the judgment result of 'yes' at least.

Through the steps, the ATCF considers whether one or more network elements for realizing media management can support the media resources created for the switched call to be used for switching the call when judging whether the anchoring media mode is adopted, if so, the network elements can use the media resources created for the switched call, and therefore, media negotiation is not needed, and the ATCF can play a corresponding role by adopting the anchoring media mode.

Preferably, the ATCF may not perform the anchor media creation call and/or the anchor media handover call if the determination result is negative. Of course, if the determination result is negative, the anchor medium may be determined according to other conditions.

The ATCF determines that the IBCF is used to implement media management and whether to support a user handover call mode of a media resource to be created for a handed over call, and in a preferred mode, the ATCF receives a message from one or more IBCFs, where the message carries information on whether the network element implements media management and information on whether the media resource created for the handed over call can be used for the handed over call. In this way, the IBCF reports the capability of the IBCF through the message, thereby providing a basis for the judgment of the ATCF.

In implementation, the information can be carried by existing messages, or can be carried by newly added messages.

For example, the ATCF may send the received registration request message and/or call request message to the one or more network elements (e.g., IBCF); the ATCF receives a registration response message and/or a call response message from the one or more network elements, where the registration response message and/or the call response message carries information on whether the network element implements media management, and information on whether media resources created for the switched call can be used for the switched call.

In another mode, the determination may also be made by the ATCF. For example, the ATCF receives a registration response message from the one or more network elements after sending the registration request message to the one or more network elements; the ATCF determines whether the network element or the network elements support the media resource created for the switched call to be used for switching the call according to the routing information carried in the registration response message and/or the ATCF local policy.

The ATCF may instruct the one or more network elements to hand over the media resource of the handed over call to the handed over call in a variety of ways, for example, the ATCF routes the handed over call to the one or more network elements; the one or more network elements hand over the media resources of the handed over call to the handed over call based on the identity of the handed over call.

Preferably, the one or more network elements may only hand over part of the resources, that is, may hand over part of the media resources of the handed over call to the handed over call; the media resources not handed over are reserved for the original call.

In this embodiment, a call processing apparatus is further provided, where the call processing apparatus is configured to implement the foregoing method, and details of the foregoing method are not repeated herein, and names of modules in the apparatus shall not be understood AS limitations of the modules, for example, a judgment module is configured to judge whether all of one or more network elements that implement media management between the ATCF and the continuity application server SCC AS support media resources to be created for a handed over call for the handed over call, and may also be expressed AS "a module configured to judge whether all of the one or more network elements that implement media management between the ATCF and the continuity application server SCC AS support media resources to be created for the handed over call", where functions of the modules described below may be implemented by a processor. Fig. 2 is a block diagram of a call processing apparatus according to an embodiment of the present invention, as shown in fig. 2, the apparatus including: a judging module 22, configured to judge whether all one or more network elements that implement media management between the ATCF and the continuity application server SCC AS support that media resources created for a switched call are used for the switched call; and a processing module 24, configured to, based at least on the determination result of yes, anchor the media creating call and/or anchor the media switching call.

Fig. 3 is a block diagram of a preferred structure of a call processing device according to an embodiment of the present invention, as shown in fig. 3, the device further includes: a receiving module 32, configured to receive a message from the one or more network elements, where the message carries information about whether the network element implements media management, and information about whether a media resource created for a switched call can be used for the switched call.

Fig. 4 is a block diagram of a preferred structure of a call processing apparatus according to an embodiment of the present invention, and as shown in fig. 4, the receiving module 32 includes: a sending unit 42, configured to send the received registration request message and/or call request message to the one or more network elements; a first receiving unit 44, configured to receive a registration response message and/or a call response message from the one or more network elements, where the registration response message and/or the call response message carry information about whether the network element implements media management, and information about whether a media resource created for a handed over call can be used for the handed over call.

Fig. 5 is a block diagram of a preferred structure of a call processing device according to an embodiment of the present invention, and as shown in fig. 5, the processing module 24 includes: a second receiving unit 52, configured to receive a registration response message from one or more network elements after sending the registration request message to the one or more network elements; and a judging unit 54, configured to judge according to the routing information and/or the ATCF local policy carried in the registration response message.

Preferably, the processing module 24 is further configured to not perform the anchor media creating call and/or not perform the anchor media switching call in case that the determination result is negative.

In this embodiment, a call processing system is further provided, fig. 6 is a block diagram of a structure of a call processing system according to an embodiment of the present invention, as shown in fig. 6, including the above apparatus, where the apparatus further includes: a routing module 26 for routing the handover call to the one or more network elements; the system further comprises: the one or more network elements are configured to hand over media resources of the handed over call to the handed over call according to the identifier of the handed over call.

The following description is given with reference to preferred embodiments. This preferred embodiment combines the above-described embodiments and their preferred embodiments. In the preferred embodiment, a call flow different from the existing specifications is provided. To accommodate the anchored media call handover requirements of the eSRVCC of the roaming user. In the preferred embodiment, whether the ATCF anchors media for the call of the eSRVCC user and whether to switch the call using the anchor media is determined according to the prior art, and whether there is an IBCF between the ATCF and the SCC AS and whether the passed IBCF supports the media resources created for the switched call. If so, the call is established by the anchoring media and switched with the anchoring media, otherwise, the mode of not anchoring the media is adopted.

In the preferred embodiment, it may be determined through registration or call flow, or the ATCF according to configuration, etc., whether there are one or more network elements (hereinafter abbreviated IBCF) between the ATCF and the SCC AS that implement media management (or referred to AS traversal, hereinafter abbreviated media management) during a call, and whether these IBCFs all support that the "media resources" created by the IBCF for a handed over call are used in the handed over call.

If the user of the ATCF access has an IBCF between the ATCF and the SCC AS in the call, but not all IBCFs support the "media resources" that the IBCF creates for the handed over call to use in the handover call, the ATCF will not anchor the media when creating (handed over) the call. If the user of the ATCF access has IBCF between the ATCF and the SCC AS in the call, but all the passed IBCF support the use of the "media resource" created by the IBCF for the handed over call in the handed over call, and the anchor media creating call is satisfied according to other judgment conditions in the prior art, the ATCF will anchor the media when creating (handed over) the call.

At handover, if the handed over call passes the IBCF (i.e. the passed IBCF supports the "media resources" created by the IBCF for the handed over call to be used in the handed over call), the ATCF implements the anchor media handover to interact with the eMSC according to the prior art and routes the handed over call to the IBCF. And the adoption of carrying appropriate routing information or IBCF cooperation ensures that the switching call passes through all IBCF network elements between the ATCF and the SCC AS of the switched call. The IBCF hands over the "media resource" of the handed over call to the handed over call according to the session unique identifier (called) of the handed over call specified in the handed over call invite and the session description Protocol (SDP for short) in the invite message (invite) being identical to the SDP of the handed over call. If the media is partially switched (namely the SDP part in the invite is the same as the SDP part of the switched call), only the media of the switched part is transferred to the switched call, and the media which is not switched is still left for the original call.

If the ATCF and IBCF do not support the functionality of the preferred embodiment, call to call handover will be implemented as in the prior art. If there is no IBCF between ATCF and SCC AS, it is realized according to the existing technology. If the ATCF determines that the call is created and the handover is performed without anchoring the media, it can be implemented according to the prior art.

By the preferred embodiment, if the IBCF supports media multiplexing, the media switching speed of the roaming user can be increased, the user experience is improved, the IBCF does not need to create new media resources for switching the call, and the resource occupation of the IBCF can be reduced. If the IBCF does not support the media multiplexing, the resource occupation of the ATGW can be reduced, and the network resources are saved.

The preferred embodiments will be described below with reference to the accompanying drawings.

Fig. 7 is a flow chart for use in handing over a call by a "media resource" that is used by the ATCF in the registration flow to know whether a subsequent call passes an IBCF and whether the passed IBCF supports the handed over call, according to an embodiment of the present invention. In fig. 7, the ATCF participates in the PS access registration process, and in the registration process, it is known whether the subsequent call passes through the IBCF and whether the passed IBCF supports the use of the "media resource" of the handed over call. As shown in fig. 7, the process includes the following steps:

at step S701, the ATCF receives a registration request message from the P-CSCF.

Step S702-703, according to the prior art, the ATCF carries the relevant information of the PS-CS handover in the registration request message sent to the I-CSCF through the IBCF.

Steps S704-706 are implemented as in the prior art.

In step S707, the IBCF fills in the registration success response message whether the IBCF (which is the IBCF through which the call flow may pass) implements media management and whether media resources created for the handed over call can be used for the handed over call.

Step S708, a registration success response is given back to the user.

If the IBCF cannot identify accurately in step S707, the ATCF may also determine according to the routing information in the registration response and in combination with the configuration and the local policy.

Fig. 8 is a first flowchart of determining to create a PS call in an anchor media manner by an ATCF access user AS a caller according to an embodiment of the present invention, where in fig. 8, the ATCF access user AS a caller determines to create a PS call in an anchor media manner according to that IBCF between the ATCF and SCC AS through which the call passes supports using "media resources" of the handed over call in the handed over call, and other existing judgment principles. As shown in fig. 8, the process includes the following steps:

in step S801, the ATCF receives a call request message from the P-CSCF.

Step S802, the ATCF access user is used AS the calling party, and the PS call is established by adopting the anchoring media mode and the anchoring media resource is established according to the IBCF between the ATCF and the SCC AS which the call passes through and other existing judgment principles, which support the use of the media resource of the switched call in the switching call.

Step S803, the ATCF routes the call according to the prior art, and the media carried in the call request message is the anchor media. Optionally, the ATCF identity is identified in the call request message and media anchoring of the call is identified.

Step S804, the IBCF performs media management on the call according to the prior art, creates media resources, and performs routing according to the prior art. Optionally, the IBCF identity is identified in the call request message, and identifies that media anchoring (also referred to herein as media management) is performed on the call, and that "media resources" for the handed over call are supported for use in handing over the call.

Steps S805 to S807 are the same as in the prior art.

Step S808, the IBCF performs media management on the call according to the prior art, and forwards the call response message according to the prior art. Optionally, the IBCF identity is identified in the call response message, and identifies that media anchoring (also referred to herein as media management) is performed on the call, and that "media resources" for the handed over call are supported for use in handing over the call.

Step S809, same as the prior art.

In the above steps, if it is determined that the media is not anchored to create a call, the procedure is the same as the prior art. If media modification is performed in the call, the ATCF and IBCF operate on media as in the prior art. Optionally, it is possible to identify in the message its own identity and whether the ATCF anchors the media and whether the IBCF supports the use of the "media resources" of the handed over call in the handover call. If a plurality of IBCF passes between the ATCF and the SCC AS during the call, the processing of each IBCF is similar to steps S804 and S807.

Fig. 9 is a flowchart of determining to create a PS call in an anchor media manner when an ATCF access user is called, where, in fig. 9, the ATCF access user is called, and the PS call is determined to be created in the anchor media manner according to that IBCF between the ATCF and SCC AS through which the call passes supports use of "media resources" of the handed over call in the handed over call, and other existing judgment principles. As shown in fig. 9, the process includes the following steps:

step S901-S902, the ATCF access user is called, the IBCF at its roaming location receives the call request from its home location, and if the IBCF is routed, the IBCF identifies its IBCF identity in its forwarded signaling and identifies its "media resource" supporting the use of the handed over call in the handed over call.

Step S903, the IBCF manages the media of the call according to the prior art, creates the media resource, and routes according to the prior art. Optionally, the IBCF identity is identified in the call request message, and identifies that media anchoring (also referred to herein as media management) is performed on the call, and that "media resources" for the handed over call are supported for use in handing over the call.

Step S904, the ATCF knows that the IBCF between the ATCF and the SCC AS, through which the call passes, supports using the "media resource" of the switched call in the switched call and other existing judgment principles, according to the registration information or/and the received call request message and/or the home policy, determines to create the PS call in the anchor media mode, and creates the anchor media resource.

Steps S905 to S907, as in the prior art.

Step S908, the ATCF forwards the call response message according to the prior art. Optionally, the ATCF identity is identified in the call response message and media anchoring of the call is identified.

In step S909, the IBCF performs media management on the call according to the prior art, and forwards the call response message according to the prior art. Optionally, the IBCF identity is identified in the call response message, and identifies that media anchoring (also referred to herein as media management) is performed on the call, and that "media resources" for the handed over call are supported for use in handing over the call.

Step S910, the same as the prior art.

In the above steps, if it is determined that the media is not anchored to create a call, the procedure is the same as the prior art. If it is determined whether to create the anchor media after receiving the response message, the flow is similar and the detailed flow chart is omitted. The media modification is carried out in the call, and the ATCF and the IBCF operate on the media as in the prior art. Optionally, it is possible to identify in the message its own identity and whether the ATCF anchors the media and whether the IBCF supports the use of the "media resources" of the handed over call in the handover call. If a plurality of IBCF passes between the ATCF and the SCC AS in the call, the processing of each IBCF is similar to steps S903 and S909.

Fig. 10 is a second flowchart of determining to create a PS call in an anchor media manner by an ATCF access user AS a caller according to an embodiment of the present invention, where in fig. 10, the ATCF access user AS a caller determines to create a PS call in an anchor media manner according to that IBCF between the ATCF and SCC AS through which the call passes supports using "media resources" of the handed over call in the handed over call, and other existing judgment principles. As shown in fig. 10, the process includes the following steps:

at step S1001, the ATCF receives a call request message from the P-CSCF.

Step S1002, the ATCF access user is called, and according to the IBCF between the ATCF and SCC AS through which the call passes, it supports using the 'media resource' of the switched call in the switching call and other existing judgment principles, it is determined to create the PS call by anchoring the media, but because the call request does not carry the media information, the media resource is not created temporarily. The ATCF routes the call as in the prior art. Optionally, the ATCF identity is identified in the call request message, and the identification may create the media resource after receiving the response message carrying the media information.

In step S1003, the IBCF routes the call according to the prior art. Optionally, the IBCF identity is identified in the call request message, and identifies the "media resources" that will perform media anchoring (herein, or referred to as media management) on the call after receiving the media-carrying response message, and support the use of the handed over call in handing over the call.

Steps S1004-S1006 are the same as in the prior art.

Step S1007, the IBCF performs media management on the call according to the prior art, creates media resources, and forwards the call response message according to the prior art. Optionally, the IBCF identity is identified in the call response message, and media anchoring (also referred to herein as media management) of the call is identified, and "media resources" supporting use of the handed over call in handing over the call are supported.

Step S1008, the ATCF knows that the IBCF between the ATCF and the SCC AS through which the call passes supports using the switched call 'media resource' and other existing judgment principles according to the registration information or/and the received call response message and/or the local policy, and determines to establish the PS call and the anchor media resource by adopting the anchor media mode.

Steps S1009 to S1011, as in the prior art.

At step S1012, the ATCF forwards the call response acknowledgement message according to the prior art. Optionally, the ATCF identity is identified in the call response acknowledgement message and media anchoring of the call is identified.

In step S1013, the IBCF performs media management on the call according to the prior art, and forwards the call response confirmation message according to the prior art. Optionally, the IBCF identity is identified in the call response acknowledgement message, and identifies that media anchoring (also referred to herein as media management) is performed on the call, and that "media resources" for the handed over call are supported for use in handing over the call.

Step S1014, as in the prior art.

In the above steps, if it is determined that the media is not anchored to create a call, the procedure is the same as the prior art. The media modification is carried out in the call, and the ATCF and the IBCF operate on the media as in the prior art. Optionally, it is possible to identify in the message its own identity and whether the ATCF anchors the media and whether the IBCF supports the use of the "media resources" of the handed over call in the handover call. If a plurality of IBCFs pass between the ATCF and the SCC AS in the call, the process of each IBCF is similar to steps S1003, S1007, and S1013.

Fig. 11 is a call flow diagram for implementing a handover from a PS access to a CS access using an ATCF according to an embodiment of the present invention, as shown in fig. 11, the flow includes the following steps:

in step S1101, the ATCF receives a request message for switching the session from the eMSC Server or PS-CS.

Step S1102, the ATCF determines to switch the call by using the anchor media mode according to the IBCF between the ATCF and the SCC AS where the switched call passes through, that all support the use of the "media resource" of the switched call in the switching call, and other existing judgment principles.

Steps S1103 to S1104 are the same as the prior art.

Step S1105, route the call to the IBCF where the original PS call is adjacent to the ATCF. And the sent invite message carries the routing information of the IBCF passed by the original PS call and the called (session unique identifier) of the switched call in sequence.

In step S1106, each IBCF determines that the handover call is the same as the media information of the handover call according to the called (session unique identifier) information of the handover call in the received invite message, and the IBCF applies the media resource of the handover call to the handover call, so that the media of the handover call and the media of the handover call on the IBCF are kept unchanged.

Step S1107, the handover call is routed to the backward IBCF (if there is also an IBCF passed by the handover call in the backward direction) or the SCC AS (if in the handover call routing, the backward IBCF is the SCC AS). The routing strategy can be from route information carried by the forward invite, and can also be from local strategy of the IBCF.

Steps S1108-S1112, as in the prior art.

In the above steps, only the switching flow after the response, the switching flow before the response, the midcall switching flow, and the additional switching flow are similar, and the specific flow is omitted. If the media information is only partially identical in step S1106, only the media resources of the same part of the handed over call are moved to the handed over call, and the different part is left for the handed over call.

In the flow shown in the above figures, whether authentication is performed in registration/subscription is not shown in the schematic flow. The messages between the network elements in the figures are mainly for clearly showing the idea of obtaining the access network handover information and the call handover. In particular implementations, these network elements and messages are not limited. The abnormal conditions occurring in various flows, the sequence of some messages in possible cases, and the specific implementation inside the network element are not specifically limited. Whether the IBCF supports the use of the 'media resources' of the switched call in the switched call or not can be carried in the call flow if the IBCF is not carried in the registration flow and the local strategy judgment of the ATCF is not adopted. CS access IMS registration, CS access IMS call, and CS-PS handover procedures, may be handled similarly. In the implementation, the ATCF and the P-CSCF can be integrated or separated.

It will be apparent to those skilled in the art that the modules or steps of the present invention described above may be implemented by a general purpose computing device, they may be centralized on a single computing device or distributed across a network of multiple computing devices, and they may alternatively be implemented by program code executable by a computing device, such that they may be stored in a storage device and executed by a computing device, or fabricated separately as individual integrated circuit modules, or fabricated as a single integrated circuit module from multiple modules or steps. Thus, the present invention is not limited to any specific combination of hardware and software.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for call processing, comprising:

an access switching control function (ATCF) judges whether one or more network elements for realizing media management between the ATCF and a continuity application server (SCC AS) support the use of media resources created for a switched call for the switched call;

the ATCF at least establishes a call and/or an anchor media switching call according to the judgment result of yes;

wherein the ATCF determining whether the one or more network elements all support using the media resource created for the handed over call comprises:

after sending the registration request message to the one or more network elements, the ATCF receives a registration response message from the one or more network elements;

and the ATCF carries out the judgment according to the routing information carried in the registration response message and/or the ATCF local policy.

2. The method of claim 1, further comprising:

and the ATCF receives a message from the one or more network elements, wherein the message carries information on whether the network element realizes media management and information on whether media resources created for the switched call can be used for the switched call.

3. The method of claim 2, wherein the ATCF receiving the message from the one or more network elements comprises:

the ATCF sends the received registration request message and/or call request message to the one or more network elements;

and the ATCF receives a registration response message and/or a call response message from the one or more network elements, where the registration response message and/or the call response message carries information on whether the network element implements media management, and information on whether media resources created for the switched call can be used for the switched call.

4. The method of any of claims 1 to 3, further comprising:

the ATCF routes the handover call to the one or more network elements;

and the one or more network elements hand over the media resource of the switched call to the switched call according to the identifier of the switched call.

5. The method of claim 4, wherein the one or more network elements handing over media resources of the handed over call to the handed over call comprises:

the one or more network elements hand over a portion of the media resources of the handed over call to the handed over call; the media resources not handed over are reserved for the original call.

6. The method of any of claims 1 to 3, further comprising:

and under the condition that the judgment result is negative, the ATCF does not carry out anchoring media establishing call or/and anchoring media switching call.

7. A call processing apparatus, located in an access handover control function, ATCF, the apparatus comprising:

a judging module, configured to judge whether all one or more network elements that implement media management between the ATCF and a continuity application server SCC AS support that a media resource created for a switched call is used for a switched call;

a processing module, for establishing call and switching call of anchoring media according to the judgment result of yes;

wherein, processing module includes: a second receiving unit, configured to receive a registration response message from the one or more network elements after sending the registration request message to the one or more network elements; and the judging unit is used for judging according to the routing information and/or the ATCF local policy carried in the registration response message.

8. The apparatus of claim 7, further comprising:

a receiving module, configured to receive a message from the one or more network elements, where the message carries information on whether the network element implements media management, and information on whether a media resource created for a switched call can be used for the switched call.

9. The apparatus of claim 8, wherein the receiving module comprises:

a sending unit, configured to send the received registration request message and/or call request message to the one or more network elements;

a first receiving unit, configured to receive a registration response message and/or a call response message from the one or more network elements, where the registration response message and/or the call response message carries information on whether the network element implements media management, and information on whether a media resource created for a switched call can be used for the switched call.

10. The apparatus according to any of claims 7 to 9, wherein the processing module is further configured to not perform an anchor media creation call and/or not perform an anchor media handover call if the determination result is no.

11. A call processing system comprising the apparatus of any one of claims 7 to 10,

the device further comprises: a routing module for routing the handover call to the one or more network elements;

the system further comprises: and the one or more network elements are used for handing over the media resources of the switched call to the switched call according to the identifier of the switched call.

12. The system of claim 11,

the one or more network elements are configured to hand over a portion of the media resources of the handed over call to the handed over call; the media resources not handed over are reserved for the original call.