WO2011000145A1

WO2011000145A1 - Method for conference calling

Info

Publication number: WO2011000145A1
Application number: PCT/CN2009/072521
Authority: WO
Inventors: 肖钰
Original assignee: Alcatel Lucent Shanghai Bell Co Ltd; Alcatel Lucent SAS
Current assignee: Nokia Shanghai Bell Co Ltd; Alcatel Lucent SAS
Priority date: 2009-06-30
Filing date: 2009-06-30
Publication date: 2011-01-06
Anticipated expiration: 2011-12-30
Also published as: CN102160330B; CN102160330A

Abstract

A method for conference calling in a communication network is provided by the present invention. The method includes: adding special identification information to a message that is sent by an application server to participants of a conference call to establish the conference call. The special identification information enables each participant to recognize the purpose of the message and to note conference status. This renders the participant unable to establish a new conference call before ending a current conference call, thereby preventing conference chaining.

Description

实现电话会议的方法技术领域 Method for realizing a conference call

本发明涉及进行电话会议的方法，尤其涉及基于 SIP协议进行电话会议的方法。背景技术 The present invention relates to a method of conducting a conference call, and more particularly to a method of conducting a conference call based on the SIP protocol. Background technique

在由公共交换电话网络（PSTN ) 向下一代网络（NGN ) 的演进过程中，电信和互联网融合业务及高级网络协议（TISPAN )标准 TS 180 043描述了通过基于会话发起协议（SIP )的消息来建立呼叫的方法。在所有的附加业务中，电话会议，即三方业务，也是通过 SIP消息进行的。在松耦合模式中定义了请求会议业务的用户的状态。用户与两个远程方建立两个对话，然后通过应用服务器请求会议业务。为该用户（会议发起者）提供服务的应用服务器将该会议以及参与者的对话记录下来。 In the evolution from the Public Switched Telephone Network (PSTN) to the Next Generation Network (NGN), the Telecommunications and Internet Converged Services and Advanced Network Protocol (TISPAN) standard TS 180 043 describes the use of Session Initiation Protocol (SIP) based messages. The method of establishing a call. Among all the additional services, the conference call, that is, the three-party service, is also carried out through SIP messages. The state of the user requesting the conference service is defined in the loosely coupled mode. The user establishes two conversations with two remote parties and then requests the conference service through the application server. The application server serving the user (meeting initiator) records the meeting and the participant's conversation.

对于会议业务而言， IP多媒体子系统（IMS )结构应当能够避免会另一会议。 For conference services, the IP Multimedia Subsystem (IMS) architecture should be able to avoid another conference.

目前，一种用于解决上述问题的方法为：应用服务器记录下电话会议参与者之间的对话，并且当这些参与者在还没有终止原来的电话会议的情况下在提出新的电话会议的请求时拒绝该请求。图 1示出了一种通信网络的拓朴结构，在该网絡中包括四个用户设备 UE-A、 UE-B、 UE-C, UE-D、一个应用服务器 AS、和一个多媒体资源功能实体（MRF ) MRF, 其中，所述四个用户设备均由 AS管辖，各个用户设备之间不能直接通信而必须通过 AS, MRF在 AS的控制下为用户设备提供会议桥以及放音、混音等媒体处理功能。假设 UE-A通过 AS已成功地发起了与 UE-B 和 UE-C的三方电话会议，在此情况下按照 SIP协议， AS知道 UE-A、 UE-B、 UE-C已处于一个电话会议中，但 UE-B、 UE-C并不知晓它们已处于一个电话会议中。如果这时 _UE__B想要发起一个与 UE-A和 UE-D 之间的电话会议，则 UE-B必须通过 AS来发起该电话会议，但是由于 AS知道 UE-B已处于一个电话会议中，因而 AS能够拒绝 UE-B提出的建立 UE-A、 UE-B和 UE-D之间的电话会议的请求，从而避免会议链的产生。 Currently, one method for solving the above problem is: The application server records the conversation between the conference call participants, and when these participants make a new conference call request without terminating the original conference call The request was rejected. 1 shows a topology of a communication network in which four user equipments UE-A, UE-B, UE-C, UE-D, an application server AS, and a multimedia resource functional entity are included in the network. (MRF) MRF, wherein the four user equipments are all governed by the AS, and the user equipments cannot communicate directly with each other but must pass the AS. The MRF provides the conference bridge for the user equipment under the control of the AS, and plays, mixes, and so on. Media processing capabilities. It is assumed that UE-A has successfully initiated a three-party conference call with UE-B and UE-C through the AS. In this case, according to the SIP protocol, the AS knows that UE-A, UE-B, and UE-C are already in a conference call. Medium, but UE-B, UE-C are not aware that they are already in a conference call. If you then _UE _ _B wants to initiate a conference call between the UE-A and UE-D, UE-B then have to initiate the conference call by AS, but because The AS knows that UE-B is already in a conference call, and thus the AS can reject the UE-B request to establish a conference call between UE-A, UE-B and UE-D, thereby avoiding the generation of a conference chain.

该方法较好地适用于用户设备 UE-A、 UE-B, UE-C由相同的应用服务器 AS管辖的情况。但是当 UE-B或者 UE-C由于各种原因（例如 UE-B或者 UE-C与 AS相距很远）而由其他应用服务器管辖时，则可能会导致会议链的产生。图 2 示出了另一种通信网络的拓朴结构。在该网络中包括第一用户设备 UE-A、第二用户设备 UE-B、第四用户设备 UE-C, 第三用户设备 UE-D、第一应用服务器 AS-A、第二应用服务器 AS-B、第一多媒体资源功能实体 MRF-A以及第二多媒体资源功能实体 MRF-B, 其中， UE-A、 UE-C和 MRF-A由 AS-A管理，而 UE-B、 UE-D 和 MRF-B由 AS-B管理，因此如果 UE-A要和 UE-B取得联系，必须先通过 AS-A, 然后由 AS-A与 AS-B通信，最后 AS-B再与 UE-B通信，反之亦然。假设 UE-A想通过 AS-A和 AS-B与 UE-B和 UE-C建立三方电话会议，在此情况下，按照 SIP协议，在建立电话会议时， AS-A发给 AS-B的消息仅用于指示 UE-B连接到 MRF-A以进行通话，从而导致在建立了该三方电话会议之后， AS-B和 UE-B并不知道 UE-B已处于一个电话会议的通话中。此时，如果 UE-B想要发起与 UE-A和 UE-D的三方电话会议，则 AS-B不会拒绝该请求，并且在建立该新的电话会议时， AS-B发给 AS-A的消息仅用于指示 UE-A连接到 MRF-B以进行通话，因此 UE-B能够成功地发起与 UE-A和 UE-D的三方电话会议，使得 UE-D加入到了 UE-A、 UE-B和 UE-C的会议中，这就产生了上述的会议链问题。 The method is preferably applied to the user equipment UE-A, UE-B, and the UE-C is governed by the same application server AS. However, when UE-B or UE-C is governed by other application servers for various reasons (for example, UE-B or UE-C is far from AS), the conference chain may be generated. Figure 2 shows the topology of another communication network. The first user equipment UE-A, the second user equipment UE-B, the fourth user equipment UE-C, the third user equipment UE-D, the first application server AS-A, and the second application server AS are included in the network. -B, a first multimedia resource function entity MRF-A and a second multimedia resource function entity MRF-B, wherein UE-A, UE-C and MRF-A are managed by AS-A, and UE-B UE-D and MRF-B are managed by AS-B, so if UE-A wants to contact UE-B, it must first pass AS-A, then AS-A communicates with AS-B, and finally AS-B Communicate with UE-B and vice versa. It is assumed that UE-A wants to establish a three-party conference call with UE-B and UE-C through AS-A and AS-B. In this case, according to the SIP protocol, when establishing a conference call, AS-A sends it to AS-B. The message is only used to indicate that UE-B is connected to MRF-A for a call, so that after the three-party conference call is established, AS-B and UE-B do not know that UE-B is already in a conference call. At this time, if UE-B wants to initiate a three-party conference call with UE-A and UE-D, AS-B will not reject the request, and when the new conference call is established, AS-B sends it to AS- The message of A is only used to indicate that UE-A is connected to MRF-B to make a call, so UE-B can successfully initiate a three-party conference call with UE-A and UE-D, so that UE-D joins UE-A, In the UE-B and UE-C conferences, this creates the above-mentioned conference chain problem.

因此，需要一种方法来有效地解决当通信网络中存在两个或两个以上应用服务器时，如何有效地避免会议链问题。发明内容 Therefore, there is a need for a method to effectively solve the problem of how to effectively avoid conference chain when there are two or more application servers in a communication network. Summary of the invention

本发明针对背景技术中的缺点，提供了一种在电话网络中实现电话会议的技术方案，通过在应用服务器向电话会议的参加者发送的用于建立电话会议的消息中加入标识信息的方法来明确告知电话会议的参加者该消息是用于建立电话会议的消息。 The present invention is directed to the shortcomings of the prior art, and provides a technical solution for implementing a conference call in a telephone network, which is used for construction by an application server to a participant of a conference call. A method of adding identification information to the message of the conference call to explicitly inform the participant of the conference call that the message is a message for establishing a conference call.

根据本发明的第一方面，提供了一种在通信网络的第一应用服务器中实现电话会议的方法，该方法包括以下步骤： a. 接收来自其管辖的第一用户设备的用于请求发起电话会议的第一消息； b.根据所述第一消息生成用于建立所述电话会议的第二消息，该第二消息包含标识信息，该标识信息用于指示该第二消息为用于建立电话会议的消息； c. 将所述第二消息发送给第二应用服务器和 /或所述第一消息中指定参加所述电话会议的、由所述第一应用服务器管辖的其他用户设备，以建立所述电话会议 According to a first aspect of the present invention, there is provided a method of implementing a conference call in a first application server of a communication network, the method comprising the steps of: a. receiving a first user equipment from its jurisdiction for requesting to initiate a call a first message of the conference; b. generating a second message for establishing the conference call according to the first message, where the second message includes identifier information, where the identifier information is used to indicate that the second message is used to establish a call a message of the conference; c. sending the second message to the second application server and/or other user equipments in the first message that are designated to participate in the conference call and are governed by the first application server, to establish The conference call

根据本发明的第二方面，提供了一种在通信网络的第二应用服务器中实现电话会议的方法，该方法包括以下步骤： A.接收来自第一应用服务器的用于建立电话会议的第二消息，该第二消息包含标识信息，该标识信息用于指示所述第二消息为用于建立电话会议的消息； B. 将所述第二消息转发给该第二消息指定的并且由所述第二应用服务器管辖的第二用户设备。 According to a second aspect of the present invention, there is provided a method of implementing a conference call in a second application server of a communication network, the method comprising the steps of: A. receiving a second from the first application server for establishing a conference call a message, the second message includes identification information, the identifier information is used to indicate that the second message is a message for establishing a conference call; B. forwarding the second message to the second message specified by the A second user device governed by the second application server.

优选地，所述第二应用服务器中存有其管辖的用户设备的会议状态；所述方法在所述步骤 B之前还包括以下步骤： ^^据所述第二消息指定的并且由所述第二应用服务器管辖的第二用户设备的会议状态，判断该第二用户设备是否已经处于一个电话会议中；所述步骤 B还包括以下步骤：如果所述第二用户设备已处于一个电话会议中，则拒绝建立所述电话会议。 Preferably, the second application server stores the conference status of the user equipment under its jurisdiction; the method further includes the following steps before the step B: ^^ according to the second message, and by the Determining, by the application server, the conference status of the second user equipment, whether the second user equipment is already in a conference call; the step B further includes the following steps: if the second user equipment is already in a conference call, Then refuse to establish the conference call.

优选地，所述方法还包括以下步骤：接收来自其所管辖的第二用户设备的用于请求发起另一电话会议的第五消息；根据所述第二用户设备的会议状态，判断所述第二用户设备是否已经处于一个电话会议中；如果所述第二用户设备已经处于一个电话会议中，则拒绝所述另一电话会议。 Preferably, the method further comprises the steps of: receiving a fifth message from the second user equipment under its jurisdiction for requesting to initiate another conference call; determining the number according to the conference status of the second user equipment Whether the two user equipments are already in a conference call; if the second user equipment is already in a conference call, the other conference call is rejected.

根据本发明的第三方面，提供了一种在通信网络的用户设备中实现电话会议的方法，其中，所述用户设备中存有该用户设备的会议状态，所述方法包括以下步骤： i.接收来自本设备所属的应用服务器的、用于建立电话会议的第二消息，其中，该第二消息中包含标识信息，该标识信息用于指示所述第二消息为用于建立电话会议的消息； ii. 建立所述电话会议，并且在建立所述电话会议之后将本用户设备的会议状态更改为已处于一个电话会议中。 According to a third aspect of the present invention, a method for implementing a conference call in a user equipment of a communication network is provided, wherein a conference state of the user equipment is stored in the user equipment, The method includes the following steps: i. receiving a second message for establishing a conference call from an application server to which the device belongs, where the second message includes identifier information, where the identifier information is used to indicate the second The message is a message for establishing a conference call; ii. establishing the conference call, and changing the conference status of the user equipment to being in a conference call after establishing the conference call.

优选地，所述方法还包括以下步骤：在本用户设备请求建立另一电话会议之前，根据本用户设备的会议状态，判断本用户设备是否已处于一个电话会议中;如果已处于一个电话会议中，则拒绝建立该另一电话会议。 Preferably, the method further includes the following steps: before the user equipment requests to establish another conference call, according to the conference status of the user equipment, determining whether the user equipment is already in a conference call; if it is already in a conference call , refuse to establish the other conference call.

由于本发明在应用服务器向电话会议的参加者发送的用于建立电话会议的消息中加入了特殊的标识信息，从而使得各个电话会议的参与者能够识别出该消息的用途，并且能够将其自身的会议状态（是否已处于一个电话会议）记录下来，这样就能够使电话会议的参加者在一个电话会议没有终止之前不能再建立另一个新的电话会议，有效地防止了会议链的发生。附图说明 Since the present invention adds special identification information to the message sent by the application server to the participants of the conference call for establishing the conference call, the participants of each conference call can recognize the purpose of the message and can themselves The status of the meeting (whether it is already in a conference call) is recorded, so that the participants of the conference call can no longer establish another new conference call before a conference call is terminated, effectively preventing the conference chain from happening. DRAWINGS

通过阅读以下结合附图对非限定性实施例的描述，本发明的其他目的、特征和优点将变得更为明显和突出。 Other objects, features, and advantages of the present invention will become more apparent from the description of the appended claims.

图 1示出了一种通信网络的拓朴结构示意图； Figure 1 shows a schematic diagram of a topology of a communication network;

图 2示出了另一种通信网络的拓朴结构示意图； 2 is a schematic diagram showing the topology of another communication network;

图 3 ( a )和图 3 ( b ) 示出了才艮据本发明的一个实施例的建立电话会议的流程图； 3(a) and 3(b) illustrate a flow chart for establishing a conference call in accordance with an embodiment of the present invention;

图 4 ( a )和图 4 ( b ) 示出了才艮据本发明的一个实施例的防止出现会议链的流程图； 4(a) and 4(b) show a flow chart for preventing a conference chain from occurring according to an embodiment of the present invention;

图 5 ( a )和图 5 ( b ) 示出了才居本发明的一个实施例的终止电话会议的流程图； Figure 5 (a) and Figure 5 (b) show a flow chart of a termination conference call in accordance with one embodiment of the present invention;

在附图中，相同或相似的附图标记代表相同或相似的方法步骤。具体实施例 In the figures, the same or similar reference numerals represent the same or similar method steps. Specific embodiment

在详细说明本发明之前，首先简要介绍一下基于 SIP协议的消息。 SIP协议是一个应用层的信令控制协议，其用于创建、修改和释放一个或多个参与者的会话。这些会话可以是 Internet多媒体会议、 IP电话或多媒体分发。会话的参与者可以通过组播（multicast )、网状单播（unicast )或两者的混合体进行通信。 SIP消息用于会话连接的建立及修改。 SIP消息分为请求（ REQUEST )和响应（ RESPONSE ) 两类消息，请求消息有 6个基本类型，包括： INVITE (发起呼叫）、 ACK (对应答做出回应）、 BYE (拆除连接）、 CANCLE (中途取消）、 OPTIONS (查询对方的能力）、 REGISTER (注册）， SIP协议的制订者还在根据需要定义新的类型。响应消息有多种编码，指示会话接受方所做出的具体响应。关于 SIP消息的格式及其他具体内容可参考相关标准，在本说明书中不再赘述。 Before describing the present invention in detail, a brief introduction to the message based on the SIP protocol will be briefly introduced. The SIP protocol is an application layer signaling control protocol used to create, modify, and release sessions for one or more participants. These sessions can be Internet multimedia conferencing, IP telephony or multimedia distribution. Participants in a session can communicate via multicast, unicast, or a mixture of the two. SIP messages are used to establish and modify session connections. SIP messages are classified into two types: request (REQUEST) and response (RESPONSE). The request message has six basic types, including: INVITE (initiating call), ACK (responding to answer), BYE (removing connection), CANCLE ( Midway cancellation), OPTIONS (query each other's capabilities), REGISTER (registration), SIP protocol developers are also defining new types as needed. The response message has multiple encodings that indicate the specific response made by the session recipient. For the format of the SIP message and other specific contents, refer to the relevant standards, and details are not described in this specification.

为了说明根据本发明的用于实现电话会议的方法，以下均以图 2 所示的通信网絡为例进行阐述。本领域的技术人员应当理解，本发明可以用于在任何 IMS架构的通信网络中实现基于 SIP协议的电话会议。 In order to explain the method for implementing a conference call according to the present invention, the communication network shown in FIG. 2 is exemplified below. Those skilled in the art will appreciate that the present invention can be used to implement SIP protocol based conference calls in any IMS architecture communication network.

以下首先参照图 2并结合图 3 ( a ) 和图 3 ( b )详细说明根据本发明的建立电话会议的步骤。 The steps of establishing a conference call in accordance with the present invention are first described in detail below with reference to FIG. 2 in conjunction with FIGS. 3(a) and 3(b).

图 3 ( a ) 和图 3 ( b ) 示出了根据本发明的一个实施例的建立电话会议的流程图。在该实施例中，第一用户设备 UE-A发起一个与第二用户设备 UE-B和第四用户设备 UE-C的三方电话会议。需要说明的是，出于简明地解释本发明的目的，在图 3 ( a ) 和图 3 ( b ) 中仅示出了与实施本发明相关的方法步骤，建立一个电话会议的过程还包括未在图中示出的其他步骤，例如在步骤 S1之前还包括 UE-A呼叫 UE-B并且保持与 UE-B的通话的步骤以及 UE-A呼叫 UE-C并且保持与 UE-C的通话的步骤。以下借助图 3 ( a ) 和图 3 ( b ) , 详细说明 UE-A与 UE-B和 UE-C建立电话会议的详细过程。 3(a) and 3(b) show a flow chart for establishing a conference call in accordance with one embodiment of the present invention. In this embodiment, the first user equipment UE-A initiates a three-party conference call with the second user equipment UE-B and the fourth user equipment UE-C. It should be noted that, for the purpose of concisely explaining the present invention, only the method steps related to the implementation of the present invention are shown in FIG. 3(a) and FIG. 3(b), and the process of establishing a conference call also includes Other steps shown in the figure, for example, before step S1, further comprising the step of UE-A calling UE-B and maintaining a call with UE-B and UE-A calling UE-C and maintaining a call with UE-C step. The detailed process of establishing a conference call between UE-A and UE-B and UE-C will be described in detail below with reference to FIG. 3(a) and FIG. 3(b).

在步骤 S1之前， UE-A已经成功地呼叫了 UE-B和 UE-C并且保持了与 UE-E和 UE-B的通话，之后的过程主要是分配第一多媒体资源功能实体 MRF-A上的会议桥并且将与会的三方连接到该会议桥上，从而实现三方会议。 Before step S1, UE-A has successfully called UE-B and UE-C and guaranteed Holding the call with UE-E and UE-B, the subsequent process is mainly to allocate the conference bridge on the first multimedia resource function entity MRF-A and connect the three parties to the conference bridge to realize the three-party conference. .

在步骤 S1 中，第一用户设备 UE-A向其所属的第一应用服务器 AS-A发送用于请求发起电话会议的第一消息，即一条 INVITE消息。在该第一消息中包括会话标识（Call-ID ) D3、电话会议的受邀者（即 UE-B和 UE-C, 其中 UE-A和 UE-B之间的会话的会话标识为 D1并且 UE-A和 UE-C之间的会话的会话标识为 D2 ) 、会议的目标地址 RURI 等信息以及基于 SDP (会话描述协议）格式的消息体，其中 SDP消息体用于对所要建立的会话的媒体特征进行描述。例如在图中所示的消息中的 SDP A表示 UE-A的特征（例如 UE-A的 IP地址、端口信息、音频编码方式、传输方向（例如图中的 a=sendrecv，其表示 UE-A既能发送消息也能接受消息）等）。 In step S1, the first user equipment UE-A sends a first message for requesting to initiate a conference call, that is, an INVITE message, to the first application server AS-A to which it belongs. In the first message, a session identifier (Call-ID) D3, an invitee of the conference call (ie, UE-B and UE-C, where the session identifier of the session between UE-A and UE-B is D1 and The session identifier of the session between UE-A and UE-C is D2), the destination address RURI of the conference, and the like, and a message body based on the SDP (Session Description Protocol) format, where the SDP message body is used for the session to be established. Media characteristics are described. For example, SDP A in the message shown in the figure indicates the characteristics of UE-A (for example, IP address, port information, audio coding mode, and transmission direction of UE-A (for example, a=sendrecv in the figure, which indicates UE-A) Can send and receive messages, etc.).

在步骤 S2中，第一应用服务器 AS-A在收到来自 UE-A的所述第一消息后，向其管辖的第一多媒体资源功能实体 MRF-A发送一条 INVITE 消息，以与 MRF-A建立会话 M3并且分配 MRF-A上的会议桥。 In step S2, after receiving the first message from UE-A, the first application server AS-A sends an INVITE message to the first multimedia resource function entity MRF-A under its jurisdiction, with the MRF. -A establishes session M3 and assigns a conference bridge on MRF-A.

在步骤 S3中， MRF-A向 AS-A返回会话 M3成功的 200 OK响应消息。 In step S3, MRF-A returns a successful 200 OK response message to session M3 to AS-A.

在步骤 S4中， AS-A向 MRF-A发送关于会话 M3的 ACK确认消息，以表明其成功地接收到了 MRF-A在步骤 S3中发出的 200 OK响应消息。步骤 S5至 S14用于将 UE-B连接到会议桥上。 In step S4, AS-A sends an ACK acknowledgment message to MRF-A regarding session M3 to indicate that it successfully received the 200 OK response message sent by MRF-A in step S3. Steps S5 to S14 are used to connect the UE-B to the conference bridge.

具体地，在步骤 S5中， AS-A向 MRF-A发送一条 INVITE消息，以与 MRF-A建立会话 M4并且分配 MRF-A上的会议桥。 Specifically, in step S5, the AS-A sends an INVITE message to the MRF-A to establish a session M4 with the MRF-A and allocate the conference bridge on the MRF-A.

在步骤 S6中， MRF-A向 AS-A返回会话 M4成功的 200 OK响应消息。 In step S6, MRF-A returns a successful 200 OK response message to session M4 to AS-A.

在步骤 S7中， AS-A生成并且向第二应用服务器 AS-B发送用于建立电话会议的第二消息，即一条 re-INVITE消息（按照 SIP协议的定义， re-INVITE 消息为当主被叫双方在已建立呼叫后，任一方想修改当前参数时所使用的消息）。该第二消息的联系标识头（ Contact-ID header ) 为： Contact: A@domain; isfocus, 其中 A@domain为会话 Dl中 UE-A 的联系标识， isfocus是根据本发明加入的标签，其由 RFC4579标准定义，该标签在本发明中用于指示该第二消息为用于建立电话会议的消白入到 re-INVITE消息中的特定实施方式。可替代地，可以不采用上述标签 isfocus , 而采用其他在该 re-INVITE消息中加入特殊标识信息的方式来达到指示该消息为用于建立电话会议的消息的目的，例如在 In step S7, AS-A generates and sends a second message for establishing a conference call to the second application server AS-B, that is, a re-INVITE message (according to the definition of the SIP protocol, the re-INVITE message is when the calling party is called After both parties have established a call, either party wants to modify the current reference. The message used when counting). The contact-ID header of the second message is: Contact: A@domain; isfocus, where A@domain is the contact identifier of UE-A in session D1, and isfocus is the label added according to the present invention, which is The RFC 4579 standard defines that the label is used in the present invention to indicate that the second message is a particular implementation for establishing a blanking of a conference call into a re-INVITE message. Alternatively, instead of using the above label isfocus, other means for adding the special identification information in the re-INVITE message may be used to achieve the purpose of indicating that the message is a message for establishing a conference call, for example,

re-INVITE消息中加入特殊的报头（header )或者加入 XML体（XML body )等等。 A special header (header) or an XML body (XML body) is added to the re-INVITE message.

应当注意的是，本发明与背景技术中的一个区别之处在于：在背景技术中，电话会议的受邀者（包括用户设备和 /或其所属的应用服务器）无法知道其将处于一个电话会议中；而在本发明中，由于电话会议的受邀者（包括用户设备和 /或其所属的应用服务器）在接收到所述含有标识信息的 re-INVITE消息后能够知道其将处于一个电话会议中，从而能够记录其自身的会议状态，此时，当用户设备自身想要建立新的电话会议或者接收到其他用户设备发起的新电话会议时，用户设备和 /或其所属的应用服务器就能够根据该用户设备的会议状态来判断是否允许建立该新的电话会议，这样就能够避免会议链的发生。 It should be noted that the present invention differs from the prior art in that: In the background art, an invitee of a conference call (including a user equipment and/or an application server to which it belongs) cannot know that it will be in a conference call. In the present invention, since the invitee of the conference call (including the user equipment and/or the application server to which it belongs) can receive the re-INVITE message containing the identification information, it can know that it will be in a conference call. In order to record its own conference state, at this time, when the user equipment itself wants to establish a new conference call or receives a new conference call initiated by another user equipment, the user equipment and/or its associated application server can It is determined whether the new conference call is allowed to be established according to the conference status of the user equipment, so that the conference chain can be avoided.

在步骤 S8中， AS-B在接收到由 AS-A在步骤 S7中发送的第二消息后，将其转发给其管辖的第二用户设备 UE-B。 In step S8, the AS-B, after receiving the second message transmitted by the AS-A in step S7, forwards it to the second user equipment UE-B under its jurisdiction.

优选地， AS-B在将该第二消息转发给 UE-B之前，先根据存储在 AS-B中的关于 UE-B的会议状态来判断 UE-B是否已经处于一个电话会议中。如果 UE-B已处于一个电话会议中，则拒绝建立由 UE-A发起的电话会议。如果 UE-B尚未处于任何电话会议中，则允许建立由 UE-A 发起的电话会议，并将所述第二消息转发给 UE-B。这样做的好处在于，能够在应用服务器端就直接判断出其管辖的用户设备是否能够接受一个电话会议的邀请，从而提高了工作效率。在步骤 S9中， UE-B在接收到由 AS-B转发的所述第二消息之后，向 AS-B返回会话成功的 200 OK响应消息。 Preferably, before forwarding the second message to the UE-B, the AS-B first determines whether the UE-B is already in a conference call according to the conference status about the UE-B stored in the AS-B. If UE-B is already in a conference call, the conference call initiated by UE-A is refused. If UE-B is not already in any conference call, then a conference call initiated by UE-A is allowed to be established and the second message is forwarded to UE-B. The advantage of this is that it can directly determine whether the user equipment under its jurisdiction can accept an invitation to a conference call on the application server side, thereby improving work efficiency. In step S9, after receiving the second message forwarded by the AS-B, the UE-B returns a 200 OK response message of the successful session to the AS-B.

在步骤 S10中， AS-B在接收到 UE-B在步骤 S9中发送的 200 OK 响应消息后将其转发给 AS-A。 In step S10, the AS-B forwards the 200 OK response message sent by the UE-B in step S9 to the AS-A.

在步骤 SI 1中， AS-A向 MRF-A发送关于会话 M4的 ACK确认消白 In step SI 1, AS-A sends an ACK confirmation confession to session M4 to MRF-A.

在步骤 S12中 , AS-A向 AS-B发送关于会话 D1的 ACK确认消息。在步骤 S13中， AS-B向 UE-B转发来自 AS-A的 ACK确认消息。在步骤 S14中， UE-B连接到了 MRF-A的会议桥上。步骤 S15至 S21用于将 UE-C连接到会议桥上。 In step S12, the AS-A sends an ACK acknowledgment message to the AS-B regarding the session D1. In step S13, the AS-B forwards an ACK acknowledgment message from the AS-A to the UE-B. In step S14, UE-B is connected to the conference bridge of the MRF-A. Steps S15 to S21 are used to connect the UE-C to the conference bridge.

具体地，在步骤 S15中， AS-A向 MRF-A发送一条 INVITE消息，以与 MRF-A建立会话 M5并且分配 MRF-A上的会议桥。 Specifically, in step S15, the AS-A sends an INVITE message to the MRF-A to establish a session M5 with the MRF-A and allocate the conference bridge on the MRF-A.

在步骤 S16中， MRF-A向 AS-A返回会话 M5成功的 200 OK响应消息。 In step S16, MRF-A returns a successful 200 OK response message to session M5 to AS-A.

在步骤 S17中， AS-A生成并且向第四用户设备 UE-C发送用于建立电话会议的包含标识信息的第二消息，以邀请 UE-C加入由 UE-A发起的三方电话会议，其中，标识信息用于指示该第二消息为用于建立电话会议的消息。 In step S17, the AS-A generates and sends a second message containing the identification information for establishing the conference call to the fourth user equipment UE-C to invite the UE-C to join the three-party conference call initiated by the UE-A, wherein The identification information is used to indicate that the second message is a message for establishing a conference call.

在步骤 S18中， UE-C在接收到来自 AS-A的第二消息后向 AS-A返回会话成功的 200 OK响应消息。 In step S18, the UE-C returns a 200 OK response message of the successful session to the AS-A after receiving the second message from the AS-A.

在步骤 S19中， AS-A向 MRF-A发送关于会话 M5的 ACK确认消在步骤 S20中， AS-A向 UE-C发送关于会话 D2的 ACK确认消息。在步骤 S21中， UE-C连接到了 MRF-A的会议桥上。步骤 S22至步骤 S29用于停止对会话 D1和 D2保持宣告并开始进行电话会议。 In step S19, AS-A transmits an ACK acknowledgment for session M5 to MRF-A. In step S20, AS-A transmits an ACK acknowledgment message for session D2 to UE-C. In step S21, the UE-C is connected to the conference bridge of the MRF-A. Steps S22 through S29 are for stopping the announcement of the sessions D1 and D2 and starting the conference call.

具体地，在步骤 S22中， AS-A向 UE-A返回会话 D3成功的 200 OK 响应消息，其用于向 UE-A表明， UE-B和 UE-C都已经连接到 MRF-A 的会议桥上了。 Specifically, in step S22, AS-A returns a successful 200 OK of session D3 to UE-A. A response message, which is used to indicate to UE-A that both UE-B and UE-C are connected to the MRF-A conference bridge.

在步骤 S23中， AS-A向 MRF-A发送拆除会话连接的 BYE消息，其用于撤销在步骤 S1之前在与 UE-B保持会话的过程中建立的保持宣告。 In step S23, the AS-A sends a BYE message to the MRF-A to remove the session connection, which is used to revoke the hold announcement established during the session with the UE-B before the step S1.

在步骤 S24中， MRF-A向 AS-A返回撤销保持宣告成功的 200 OK BYE响应消息。 In step S24, the MRF-A returns a 200 OK BYE response message to the AS-A to cancel the reservation success.

在步骤 S25中， AS-A向 MRF-A发送拆除会话连接的 BYE消息，其用于撤销在步骤 S1之前在与 UE-C保持会话的过程中建立的保持宣告。 In step S25, the AS-A sends a BYE message to the MRF-A to remove the session connection, which is used to revoke the hold announcement established during the session with the UE-C prior to step S1.

在步骤 S26中， MRF-A向 AS-A返回撤销保持宣告成功的 200 ΌΚ BYE响应消息。 In step S26, the MRF-A returns a 200 ΌΚ BYE response message to the AS-A to cancel the reservation success.

在步骤 S27中， UE-A向 AS-A发出关于会话 D3的 ACK确认消息，以向 AS-A表明 UE-A已经知道 UE-B和 UE-C都已经连接在 MRF-A的会议桥上了。 In step S27, UE-A sends an ACK acknowledgment message to AS-A regarding session D3 to indicate to AS-A that UE-A already knows that both UE-B and UE-C are connected to the conference bridge of MRF-A. It is.

在步骤 S28中， UE-A连接到了 MRF-A的会议桥上。 In step S28, UE-A is connected to the conference bridge of the MRF-A.

在步骤 S29中 , UE-A、 UE-B和 UE-C开始进行三方电话会议，此时， AS-A和 AS-B将其记录的关于 UE-A、 UE-B和 UE-C的会议状态更改为已处于一个电话会议中，并且 UE-A、 UE-B和 UE-C也将自己的会议状态更改为已处于一个电话会议中。 In step S29, UE-A, UE-B and UE-C start a three-party conference call, at which time AS-A and AS-B record their conferences on UE-A, UE-B and UE-C. The status changes to already in a conference call, and UE-A, UE-B, and UE-C also change their own conference status to already in a conference call.

以上对 UE-A发起的与 UE-B和 UE-C的三方电话会议的建立过程做了详细说明。以下参照图 2并结合图 4 ( a ) 和图 4 ( b )详细说明本发明是如何抑制会议链的产生的。 The above process of establishing a three-party conference call initiated by UE-A with UE-B and UE-C is described in detail. The following is a detailed description of how the present invention suppresses the generation of a conference chain with reference to Fig. 2 in conjunction with Figs. 4(a) and 4(b).

图 4 ( a )和图 4 ( b ) 示出了才艮据本发明的一个实施例的防止出现会议链的流程图。在该实施例中， UE-A、 UE-B和 UE-C已处于一个电话会议中，此时 UE-B想要发起一个与 UE-D和 UE-A的电话会议。由于 UE-D是现有会议之外的用户设备，一旦这个电话会议被建立，那么就会产生会议链问题，因此必须拒绝该电话会议的建立。此外，需要说明的是，出于简明的目的，在图 4 ( a ) 和图 4 ( b ) 中仅示出了与实施本发明相关的方法步骤。 4(a) and 4(b) show a flow chart for preventing the occurrence of a conference chain in accordance with an embodiment of the present invention. In this embodiment, UE-A, UE-B, and UE-C are already in a conference call, at which point UE-B wants to initiate a conference call with UE-D and UE-A. Since the UE-D is a user equipment outside the existing conference, once the conference call is established, a conference chain problem arises, so the establishment of the conference call must be rejected. In addition, it should be noted that for the sake of brevity, only the real and the real are shown in Figure 4 (a) and Figure 4 (b) The method steps associated with the invention are applied.

在步骤 S30至步骤 S32中， UE-A、UE-B和 UE-C均已连接在 MRF-A 的会议桥上。 In step S30 to step S32, UE-A, UE-B and UE-C are both connected to the conference bridge of the MRF-A.

为了建立与 UE-A和 UE-D的电话会议， UE-B首先要保持住与 UE-A 的通话，然后再呼叫 UE-D并且保持住与 UE-D的通话，最后再将它们连接到 MRF-B上才能建立该电话会议。步骤 S33至 S50用于保持会话 D1。 In order to establish a conference call with UE-A and UE-D, UE-B first needs to hold a call with UE-A, then call UE-D and hold the call with UE-D, and finally connect them to The conference call can be established on the MRF-B. Steps S33 to S50 are for maintaining the session D1.

具体地，在步骤 S33中 , UE-B向 AS-B发送一条关于会话 D1的 re-INVITE消息，其用于保持 UE-B与 UE-A之间的通话。 Specifically, in step S33, the UE-B sends a re-INVITE message to the AS-B regarding the session D1, which is used to maintain the call between the UE-B and the UE-A.

在步骤 S34中， AS-B将来自 UE-B的 re-INVITE消息转发给 AS-A。在步骤 S35中，由于 UE-A和 UE-B已经连接在 MRF-A的会议桥上，因而 AS-A并不将在步骤 S34中由 AS-B发送的 re-INVITE消息转发给 UE-A, 而是另发一条关于会话 M4的 re-INVITE消息给 MRF-A。 In step S34, AS-B forwards the re-INVITE message from UE-B to AS-A. In step S35, since UE-A and UE-B are already connected to the conference bridge of MRF-A, AS-A does not forward the re-INVITE message sent by AS-B in step S34 to UE-A. Instead, send another re-INVITE message about session M4 to MRF-A.

在步骤 S36中 , MRF-A向 AS-A返回会话成功的 200 OK响应消息。在步骤 S37中， AS-A向 UE-B返回保持成功的 200 OK响应消息。在步骤 S38中， UE-B向 AS-B发送关于会话 D1的 ACK确认消息。在步骤 S39中， AS-B将来自 UE-B的 ACK确认消息转发给 AS-A。在步骤 S40中， AS-A向 MRF-A发送关于会话 M4的 ACK确认消在步骤 S41中， AS-B向 MRF-B发送一条 INVITE消息，用于与 MRF-B建立会话 M6。 In step S36, the MRF-A returns a 200 OK response message of the successful session to the AS-A. In step S37, the AS-A returns a 200 OK response message that remains successful to the UE-B. In step S38, the UE-B transmits an ACK acknowledgment message regarding the session D1 to the AS-B. In step S39, the AS-B forwards the ACK acknowledgment message from the UE-B to the AS-A. In step S40, the AS-A sends an ACK acknowledgment to the MRF-A regarding the session M4. In step S41, the AS-B sends an INVITE message to the MRF-B for establishing a session M6 with the MRF-B.

在步骤 S42中， MRF-B向 AS-B返回会话成功的 200 OK响应消息。在步骤 S43中， AS-B向 AS-A发送一条关于会话 D1的 re-INVITE 消息，用于建立对 UE-A的保持宣告。 In step S42, the MRF-B returns a 200 OK response message of the successful session to the AS-B. In step S43, the AS-B sends a re-INVITE message to the AS-A regarding the session D1 for establishing a hold announcement for the UE-A.

在步骤 S44中，由于 UE-A和 UE-B已经连接在 MRF-A的会议桥上，因而 AS-A并不将在步骤 S43中由 AS-B发送的 re-INVITE消息转发给 UE-A, 而是另发一条关于会话 M4的 re-INVITE消息给 MRF-A。 In step S44, since UE-A and UE-B are already connected to the conference bridge of MRF-A, AS-A does not forward the re-INVITE message sent by AS-B in step S43 to UE-A. Instead, send another re-INVITE message about session M4 to MRF-A.

在步骤 S45中， MRF-A向 AS-A返回关于会话 M4的 200 OK响应消息。 In step S45, MRF-A returns a 200 OK response to session M4 to AS-A. Message.

在步骤 S46中， AS-A向 AS-B返回关于会话 D1的 200 OK响应消白 In step S46, AS-A returns a 200 OK response fade to session D1 to AS-B.

在步骤 S47中， AS-B向 MRF-B发送关于会话 M6的 ACK确认消在步骤 S48中， AS-B向 AS-A发送关于会话 D1的 ACK确认消息。在步骤 S49中， AS-B向 UE-B发送关于会话 D1的 ACK确认消息。在步骤 S50中， MRF-B向 MRF-A发出 MRF-B关于会话 D1 (即 UE-A和 UE-B之间的会话）的保持宣告。步骤 S51至 S59用于建立 UE-B和 UE-D之间的会话。 In step S47, the AS-B transmits an ACK acknowledgment for the session M6 to the MRF-B. In step S48, the AS-B transmits an ACK acknowledgment message regarding the session D1 to the AS-A. In step S49, the AS-B transmits an ACK acknowledgment message regarding the session D1 to the UE-B. In step S50, the MRF-B issues a MRF-B reservation announcement to the MRF-A regarding the session D1 (i.e., the session between UE-A and UE-B). Steps S51 to S59 are used to establish a session between UE-B and UE-D.

具体地，在步骤 S51中， UE-B向 AS-B发送呼叫 UE-D的 INVITE 消息，其中， UE-B与 UE-D之间的会话的会话标识为 D4。 Specifically, in step S51, the UE-B sends an INVITE message to the AS-B to the UE-D, where the session identifier of the session between the UE-B and the UE-D is D4.

在步驟 S52中， AS-B将来自 UE-B的 INVITE消息转发给 UE-D。在步骤 S53中， UE-D向 AS-B发送 180 Ring振铃消息。 In step S52, AS-B forwards the INVITE message from UE-B to UE-D. In step S53, UE-D sends a 180 Ring Ringing message to AS-B.

在步骤 S54中， AS-B将 180 Ring振铃消息转发给 UE-B。 In step S54, AS-B forwards the 180 Ring ringing message to UE-B.

在步骤 S55中 , UE-D向 AS-B返回关于会话 D4的 200 OK响应消白 In step S55, UE-D returns a 200 OK response fade to session D4 to AS-B.

在步骤 S56中， AS-B将关于会话 D4的 200 OK响应消息转发给 UE-B。 In step S56, AS-B forwards the 200 OK response message for session D4 to UE-B.

在步骤 S57中 , UE-B向 AS-B发送关于会话 D4的 ACK确认消息。在步骤 S58中 , AS-B将关于会话 D4的 ACK确认消息转发给 UE-D。在步骤 S59中 , UE-B与 UE-D的会话 D4建立成功。 In step S57, the UE-B transmits an ACK acknowledgment message regarding the session D4 to the AS-B. In step S58, AS-B forwards the ACK acknowledgment message regarding session D4 to UE-D. In step S59, the session D4 of UE-B and UE-D is successfully established.

接下来， UE-B想要建立与 UE-A和 UE-D的电话会议。在本发明中，当用户设备知道其已经加入了一个电话会议时，在该用户设备未退出原来的电话会议之前将拒绝其发起的一个新的电话会议。在本实施例中，由于 UE-A、 UE-B. UE-C已处于一个电话会议中，因而 UE-B在检验了其自身的会议状态后，不再发起与 UE-A和 UE-D的电话会议。此外，根据本发明，管辖 UE-B的第二应用服务器 AS-B同样能够知道 UE-B的会议状态，因此在本实施例中即使 UE-B错误地发出了发起电话会议的请求， AS-B也能有效地加以阻止。以下对 AS-B拒绝建立该电话会议的过程加以描述。 Next, UE-B wants to establish a conference call with UE-A and UE-D. In the present invention, when the user equipment knows that it has joined a conference call, it will reject a new conference call initiated by the user equipment before it leaves the original conference call. In this embodiment, since UE-A, UE-B. UE-C is already in a conference call, UE-B does not initiate UE-A and UE-D after verifying its own conference state. Conference call. Furthermore, according to the present invention, the second application server AS-B governing UE-B can also know The conference state of UE-B, therefore, in this embodiment, even if UE-B erroneously issues a request to initiate a conference call, AS-B can effectively block it. The following describes the process by which AS-B refuses to establish the conference call.

首先，在步骤 S60至 S69中， UE-B对与 UE-D的会话进行保持，此过程与上文中的保持过程类似，故不再赘述。 First, in steps S60 to S69, the UE-B maintains the session with the UE-D. This process is similar to the above-mentioned holding process, and therefore will not be described again.

在步骤 S70中， UE-B向 AS-B发送请求发起另一电话会议的第四消息，即一条 INVITE消息。在该第一消息中包括会话的标识 D5、电话会议的受邀者（即 UE-A和 UE-D, 其中 UE-A和 UE-B的会话标识为 D1并且 UE-B和 UE-D的会话标识为 D4 ) 、会议的目标地址 RU I等信息。 In step S70, the UE-B sends a fourth message, that is, an INVITE message, to the AS-B requesting to initiate another conference call. In the first message, the identifier D5 of the session, the invitees of the conference call (ie, UE-A and UE-D, where the session identifiers of UE-A and UE-B are D1 and UE-B and UE-D are included) The session ID is D4), the destination address of the conference, RU I, and so on.

在步骤 S71中， AS-B在收到该第四消息时，根据存储在 AS-B内的关于 UE-B的会议状态，确定 UE-B正处于一个电话会议中，因此拒绝该请求，并向 UE-B返回消息 3xx或 4xx或 5xx或 6xx以向 UE-B表明其建立电话会议的请求被拒绝了 , 其中 XX表示可以是 SIP协议中定义的任何状态码。 In step S71, when receiving the fourth message, the AS-B determines that the UE-B is in a conference call according to the conference status of the UE-B stored in the AS-B, and therefore rejects the request, and The message 3xx or 4xx or 5xx or 6xx is returned to UE-B to indicate to UE-B that its request to establish a conference call is rejected, where XX indicates that it may be any status code defined in the SIP protocol.

在步骤 S72中， UE-B向 AS-B发送一条 INVITE消息，用于请求会议发起失败的宣告。 In step S72, the UE-B sends an INVITE message to the AS-B for requesting the conference to initiate the failure.

在步骤 S73中， AS-B向 MRF-B发送一条 INVITE消息，用于建立会话 M8。 In step S73, the AS-B sends an INVITE message to the MRF-B for establishing the session M8.

在步骤 S74中， MRP-B向 AS-B返回关于会话 M8的 200 OK响应消息。 In step S74, MRP-B returns a 200 OK response message regarding session M8 to AS-B.

在步骤 S75中， AS-B向 UE-B发送 183会话进展响应消息。在步骤 S76中 , AS-B向 MRF-B发送关于会话 M8的 ACK确认消息。 In step S75, the AS-B sends a 183 Session Progress Response message to the UE-B. In step S76, the AS-B sends an ACK Acknowledgement message to the MRF-B regarding the session M8.

在步骤 S77中， AS-B向 UE-B宣告电话会议未被建立。 In step S77, the AS-B announces to the UE-B that the conference call has not been established.

以上对本发明如何防止会议链的产生做了详细说明。根据本实施例的一种变型，当用户设备 UE-A、 UE-B和 UE-C正处于一个电话会议中并且第三用户设备 UE-D未处于任何电话会议中时， UE-D 想要建立与 UE-A和 UE-B的电话会议。此时， UE-D向 AS-B发送用于请求建立另一电话会议的第五消息。 AS-B在接收到该第五消息后根据 UE-D的会议状态，得知 UE-D未处于任何电话会议中。在此情况样由其管辖的其他用户设备，在本实施例中， UE-B就是这样的用户设备；接着 AS-B经检查后发现 UE-B已处于一个电话会议中，因而拒绝由 UE-D发起的电话会议。这样做的优点在于， AS-B能够在接收到由 UE-D发送的建立电话会议的请求后直接拒绝该请求，从而避免了与其他应用服务器或者其他用户设备传送多次消息后才将其拒绝，提高了工作效率。 The above has explained in detail how the invention prevents the generation of a conference chain. According to a variant of the embodiment, when the user equipment UE-A, UE-B and UE-C are in a conference call and the third user equipment UE-D is not in any conference call, the UE-D wants Establish a conference call with UE-A and UE-B. At this time, UE-D sends to AS-B. A fifth message for requesting the establishment of another conference call. After receiving the fifth message, the AS-B learns that the UE-D is not in any conference call according to the conference state of the UE-D. In this embodiment, other user equipments under its jurisdiction, in this embodiment, UE-B is such a user equipment; after AS-B checks, it is found that UE-B is already in a conference call, and thus is rejected by the UE- D initiated a conference call. The advantage of this is that the AS-B can directly reject the request after receiving the request to establish a conference call sent by the UE-D, thereby avoiding rejecting it after transmitting multiple messages with other application servers or other user equipments. ,Improve work efficiency.

以下参照图 2并结合图 5 ( a ) 和图 5 ( b )就如何撤销已建立的电话会议的步骤加以详细说明。 The steps of how to cancel an established conference call are described in detail below with reference to Figure 2 in conjunction with Figures 5(a) and 5(b).

图 5 ( a )和图 5 ( b ) 示出了才艮据本发明的一个实施例的终止电话会议的流程图。在该实施例中，用户设备 UE-A、 UE-B和 UE-C已处于一个电话会议中，第一用户设备 UE-A是该电话会议的发起者，其现在想终止该电话会议，并且保持与 UE-B的通话，以及与 UE-C进行通话。需要说明的是，出于简明的目的，在图 5 ( a )和图 5 ( b ) 中仅示出了与实施本发明相关的方法步骤。 Figures 5(a) and 5(b) show a flow chart for terminating a conference call in accordance with one embodiment of the present invention. In this embodiment, the user equipments UE-A, UE-B and UE-C are already in a conference call, the first user equipment UE-A is the originator of the conference call, which now wants to terminate the conference call, and Keep a call with UE-B and a call with UE-C. It should be noted that for the sake of brevity, only the method steps related to the implementation of the present invention are shown in Figures 5(a) and 5(b).

步骤 S78至 S83用于使会议桥静音。 Steps S78 to S83 are used to mute the conference bridge.

具体地，在步骤 S78中， UE-A向 AS-A发出一条关于会话 D3 (即 UE-A、 UE-B和 UE-C之间的电话会议 ) 的 re-INVITE消息，其用于指示会议桥静音。 Specifically, in step S78, UE-A sends a re-INVITE message to AS-A regarding session D3 (ie, a conference call between UE-A, UE-B, and UE-C), which is used to indicate the conference. The bridge is muted.

在步骤 S79中， AS-A将来自 UE-A的 re-INVITE消息转发给 MRF-A。 In step S79, AS-A forwards the re-INVITE message from UE-A to MRF-A.

在步骤 S80中 , MRF-A向 AS-A返回 200 OK INVITE响应消息，以表明会议桥已静音。 In step S80, the MRF-A returns a 200 OK INVITE response message to the AS-A to indicate that the conference bridge is muted.

在步骤 S81中， AS-A将来自 MRP-A的 200 OK INVITE响应消息转发给 UE-A。 In step S81, AS-A forwards the 200 OK INVITE response message from MRP-A to UE-A.

在步骤 S82中， UE-A向 AS-A发送 ACK确认消息，以表明其接收到了上述 200 OK INVITE响应消息。在步骤 S83中 , AS-A将该 ACK确认消息转发给 MRF-A。步骤 S84至 S101用于终止电话会议并保持 UE-A与 UE-B的会话 Dl。 In step S82, UE-A sends an ACK acknowledgement message to AS-A to indicate that it has received the above 200 OK INVITE response message. In step S83, AS-A forwards the ACK confirmation message to MRF-A. Steps S84 to S101 are for terminating the conference call and maintaining the session D1 between UE-A and UE-B.

具体地，在步骤 S84中， UE-A向 AS-A发送用于终止电话会议的第三消息，即一条 re-INVITE消息。将该第三消息与上文所述的用于建立电话会议的第二消息进行比较，可以发现该第三消息中不存在标签 isfocus。也就是说，用于建立电话会议的第二消息与用于终止电话会议的第三消息的不同之处主要在于，用于终止电话会议的第三消息中不带有上文所述的标识信息，从而使得用户设备和 /或应用服务器在接收到该第三消息后能够知道本用户设备将退出一个已有的电话会议，从而将其会议状态更改为不处于任何电话会议中，这样就可以发起或者接受另一新的电话会议了。 Specifically, in step S84, the UE-A sends a third message for terminating the conference call to the AS-A, that is, a re-INVITE message. Comparing the third message with the second message for establishing a conference call as described above, it can be found that the tag isfocus does not exist in the third message. That is, the second message used to establish the conference call differs from the third message used to terminate the conference call mainly in that the third message for terminating the conference call does not carry the identification information described above. So that the user equipment and/or the application server can know that the user equipment will quit an existing conference call after receiving the third message, thereby changing the conference status to not being in any conference call, so that the user equipment and/or the application server can initiate Or accept another new conference call.

在步骤 S85中， AS-A将上述第三消息转发给 AS-B。 In step S85, the AS-A forwards the third message to the AS-B.

在步骤 S86中， AS-B将上述第三消息转发给 UE-B。 In step S86, the AS-B forwards the third message to the UE-B.

在步骤 S87中， UE-B向 AS-B返回 200 OK响应消息。 In step S87, UE-B returns a 200 OK response message to AS-B.

在步骤 S88中， AS-B向 AS-A转发来自 UE-B的 200 OK响应消在步骤 S89中， AS-A将该 200 OK响应消息转发给 UE-A。 In step S88, the AS-B forwards the 200 OK response from the UE-B to the AS-A. In step S89, the AS-A forwards the 200 OK response message to the UE-A.

在步骤 S90中， UE-A向 AS-A发送 ACK确认消息。 In step S90, UE-A sends an ACK acknowledgement message to AS-A.

在步骤 S91 中， AS-A向 AS-B转发该 ACK确认消息。 In step S91, the AS-A forwards the ACK acknowledgement message to the AS-B.

在步骤 S92中， AS-B向 UE-B转发该 ACK确认消息并且将 UE-B 的会议状态更改为未处于任何电话会议中。 UE-B在接收到该 ACK 确认消息之后，也将自己的会议状态更改为未处于任何电话会议中。 In step S92, the AS-B forwards the ACK acknowledgment message to the UE-B and changes the conference status of the UE-B to not in any conference call. After receiving the ACK acknowledgement message, UE-B also changes its own conference status to not being in any conference call.

在步骤 S93中， AS-A向 MRF-A发送释放会议桥连接资源的消息 BYE。 In step S93, the AS-A sends a message BYE releasing the conference bridge connection resource to the MRF-A.

在步骤 S94中， MRF-A向 AS-A返回 200 OK BYE响应消息。在步骤 S95至 S101中为产生对会话 D1的保持宣言的过程，由于该过程与前文所述的产生保持宣言的过程类似，故不再赘述。步骤 S102至 SI 10用于终止电话会议并使 UE-A和 UE-C处于通话状态。 In step S94, MRF-A returns a 200 OK BYE response message to AS-A. In order to generate a declaration of the hold of the session D1 in steps S95 to S101, since the process is similar to the process of generating the hold declaration described above, it will not be described again. Steps S102 to SI 10 are for terminating the conference call and placing UE-A and UE-C in a call state.

具体地，在步骤 S102中， UE-A向 AS-A发送用于终止电话会议的第三消息。 Specifically, in step S102, UE-A sends a third message to terminate the telephone conference to AS-A.

在步骤 S103中 , AS-A向 MRF-A发送释放会议桥连接资源的 BYE消息。 In step S103, the AS-A sends a BYE message to the MRF-A to release the conference bridge connection resource.

在步骤 S104中， MRF-A向 AS-A返回 200 OK BYE响应消息。在步骤 S105中， AS-A向 UE-C转发在步骤 S102中由 UE-A发送的第三消息。 In step S104, MRF-A returns a 200 OK BYE response message to AS-A. In step S105, the AS-A forwards the third message transmitted by the UE-A in step S102 to the UE-C.

在步骤 S106中， UE-C向 AS-A返回 200 OK响应消息。 In step S106, the UE-C returns a 200 OK response message to the AS-A.

在步骤 S107中， AS-A向 UE-A转发该 200 OK响应消息。 In step S107, the AS-A forwards the 200 OK response message to the UE-A.

在步骤 S108中， UE-A向 AS-A发送 ACK确认消息。 In step S108, UE-A sends an ACK Acknowledgement message to AS-A.

在步骤 S109中 , AS-A将该 ACK确认消息转发给 UE- (：。这样，在 UE-C接收到该 ACK确认消息之后就可以将其自身的会议状态更改为未处于任何电话会议中。 In step S109, the AS-A forwards the ACK acknowledgment message to the UE- (:. Thus, after the UE-C receives the ACK acknowledgment message, it can change its own conference state to not be in any conference call.

在步骤 S110中， UE-A和 UE-C进行通话。在步骤 S111中， UE-A向 AS-A发出撤销会话 D3的 BYE消息。在步骤 S112中， AS-A向 MRF-A发出撤销会话 M3的 BYE消白 In step S110, UE-A and UE-C make a call. In step S111, UE-A issues a BYE message to AS-A to revoke session D3. In step S112, AS-A issues a BYE eliminator to the MRF-A to cancel the session M3.

在步骤 S113中， MRF-A向 AS-A返回对撤销会话 M3的 BYE 消息的 200 OK BYE响应消息。 In step S113, MRF-A returns a 200 OK BYE response message to the AS-A for the BYE message of the revocation session M3.

在步骤 S114中， AS-A向 UE-A返回对撤销会话 D3的 BYE消息的 200 OK BYE响应消息。在 UE-A接收到该 200 OK BYE响应消息之后， UE-A更改其会议状态为未处于任何电话会议中。 In step S114, the AS-A returns a 200 OK BYE response message to the UE-A for revoking the BYE message of the session D3. After UE-A receives the 200 OK BYE response message, UE-A changes its conference status to not be in any conference call.

以上对 UE- A终止电话会议的一个实施例进行了详细说明。根据本实施例的一个变型，为了终止电话会议， UE-A可以例如在步骤 S84中直接向 AS-A发送一条 BYE消息，其结果是不仅电话会议终止了而且也中断了与 UE-B和 UE-C的会话。此外，在电话会议进行时， UE-B或者 UE-C也可以退出电话会议，例如其向 AS-A或 AS-B 发送一条 BYE消息，在收到 AS-A或 AS-B的确认消息之后，就可以改变自己的会议状态，从而能够发起或者加入另一电话会议。 One embodiment of the UE-A termination conference call is described in detail above. According to a variant of this embodiment, in order to terminate the conference call, UE-A may send a BYE message directly to AS-A, for example in step S84, with the result that not only the conference call is terminated but also the UE-B and UE are also interrupted. -C session. In addition, in a conference call At the same time, UE-B or UE-C can also exit the conference call. For example, it sends a BYE message to AS-A or AS-B. After receiving the confirmation message of AS-A or AS-B, it can change its own. The status of the meeting so that it can initiate or join another conference call.

以上对本发明的具体实施方式进行了描述。需要说明的是，本发明并不局限于上述特定实施方式，本领域技术人员可以在所附权利要求的范围内做出各种变型或修改。 The specific embodiments of the present invention have been described above. It should be noted that the present invention is not limited to the specific embodiments described above, and various modifications or changes can be made by those skilled in the art within the scope of the appended claims.

Claims

Claim

A method of implementing a conference call in a first application server of a communication network, the method comprising the steps of:

Receiving a first message from the first user equipment under its jurisdiction for requesting to initiate a conference call;

And generating a second message for establishing the conference call according to the first message, where the second message includes identifier information, where the identifier information is used to indicate that the second message is a message for establishing a conference call;

c transmitting the second message to the second application server and/or other user equipments in the first message that are designated to participate in the conference call and are governed by the first application server to establish the conference call.

2. The method of claim 1 wherein the method further comprises the steps of:

- after the first application server receives the third message from the first user equipment for terminating the conference call, forwarding the third message to the second application server and/or in addition to the first A user device other than the user device that participates in the conference call and is governed by the first application server.

The method according to claim 1, wherein the conference call is a session initiation protocol based conference call, and the second message is an invite message (re-INVITE) defined in a session initiation protocol, where An identifier (isfocus) is attached to the contact identifier of the invitation message (re-INVITE), and the tag (isfocus) is used as the identification information.

A method for implementing a conference call in a second application server of a communication network, wherein the second application server stores a conference status of a user equipment under its jurisdiction, and the method includes the following steps:

Receiving a second message from the first application server for establishing a conference call, the second message includes identification information, where the identifier information is used to indicate that the second message is a message for establishing a conference call;

B. forwarding the second message to the second message specified by the second application The second user device under the jurisdiction of the server.

5. The method of claim 4, wherein

The method further includes the following steps before the step B:

Determining, according to the conference status of the second user equipment that is specified by the second message and is governed by the second application server, whether the second user equipment is already in a conference call;

The step B further includes the following steps:

If the second user equipment is already in a conference call, the telephone conference is refused to be established;

The method according to claim 5, wherein the step B further comprises the following steps:

If the second user equipment is not in any conference call, allowing the conference call to be established, and forwarding the second message to the second device;

The method further includes:

After the conference call is established, the conference status of the second user equipment is changed to be in a conference call in the second application server.

7. The method of claim 4, wherein the method further comprises the steps of:

And when the second application server receives a third message from the first application server for instructing termination of the conference call, forwarding the third message to the second user equipment;

After the conference call is terminated, the conference state of the second user equipment is changed to not yet in any conference call.

The method according to claim 4, wherein the method further comprises the following steps:

Receiving a fourth message from the second user equipment under its jurisdiction for requesting to initiate another conference call;

Determining, according to the conference status of the second user equipment, whether the second user equipment is already in a conference call; If the second user device is already in a conference call, the other conference call is rejected.

9. The method of claim 4, wherein the method further comprises the steps of:

Receiving a fifth message from a third user equipment of its jurisdiction for requesting to initiate another conference call;

Determining, according to the conference status of the third user equipment, whether the third user equipment is already in a conference call;

If the third user equipment is not already in a conference call, further determining whether there are other user equipments in the participants of the other conference call that are also governed by the second application server;

If so, based on the conference status of the other user equipment, it is determined whether the other user equipment is already in a conference call, and if it is already in a conference call, the other conference call is rejected.

The method according to any one of claims 4 to 9, wherein the conference call is a session initiation protocol based conference call, and the second message is an invitation message defined in a session initiation protocol (re - INVITE ), a label (isfocus) is attached to the contact identifier of the invite message (re-INVITE), and the label (isfocus) is used as the identification information.

A method for implementing a conference call in a user equipment of a communication network, wherein the user equipment has a conference state of the user equipment, and the method includes the following steps: i. receiving an application from the device a second message of the server for establishing a conference call, where the second message includes identification information, where the identifier information is used to indicate that the second message is a message for establishing a conference call;

Ii. Establish the conference call and change the conference status of the user equipment to be in a conference call after the conference call is established.

12. The method of claim 11 further comprising the steps of:

- after receiving a third message from the application server to which the user equipment belongs indicating the termination of the conference call, terminating the conference call and changing the conference status of the user equipment Not in any conference call.

13. The method of claim 1 1 further comprising the steps of:

- issuing a message to the application server to which the user equipment belongs to exit the conference call; - changing the conference status of the user equipment to not be in any conference call after the conference call is terminated.

14. The method of claim 1 1 wherein the method further comprises the steps of:

- before the user equipment sends a request message for establishing another conference call, according to the conference status of the user equipment, it is determined whether the user equipment is already in a conference call; - if it is already in a conference call, refuse to establish the other A conference call.

The method according to any one of claims 1 to 14, wherein the conference call is a session initiation protocol based conference call, and the second message is an invitation message defined in a session initiation protocol ( re-INVITE), a label (isfocus) is added to the contact identifier of the invite (re-INVITE) message, and the label (isfocus) is used as the identification letter