WO2008095436A1

WO2008095436A1 - Method, communication system and device for achieving media stream remote control

Info

Publication number: WO2008095436A1
Application number: PCT/CN2008/070199
Authority: WO
Inventors: Yun He; Xiao Wang; Dongming Zhu; Peili Xu; Peng Wang
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-02-02
Filing date: 2008-01-28
Publication date: 2008-08-14
Also published as: CN101237389A; CN101237389B

Abstract

A method for achieving media stream remote control includes that: the controlled point (320) receives SIP invite information carrying operation indication information sent by the controlling point (310) (201), and it carries out the session operation and/or media stream operation remotely indicated by the controlling point (310) according to said operation indication information (202). Using this method, it could be achieved that the controlling point (310) can directly control the indicated media stream operation of the controlled point (320). Furthermore, the operation indication of the multiple sessions and corresponding media stream could be carried in the operation indication information, therefore, it could be achieved that one SIP invite can remotely control multiple sessions. And a communication system, controlling device and controlled device for achieving media stream remote control.

Description

Method, communication system and device for realizing remote media flow control

Technical field

The present invention relates to communication technologies, and in particular, to a method, a communication system and a device for implementing remote media stream control. Background of the invention

The Session Initiation Protocol (SIP) is one of the multimedia communication system framework protocols developed by the Internet Engineering Task Force (IETF) and is a text-based application layer control protocol. It is independent of the underlying protocol and is used to establish, modify, and terminate multimedia sessions over the IP network. In the SIP protocol, a multimedia session consists of a set of multimedia senders and receivers and their data flows between each other. The session uses a SIP conversation and follows the SIP rules when sending requests during the conversation. A conversation is a SIP relationship between two communicating parties that provides the necessary state information on which to route and sequence messages between communicating parties. The SIP User Agent (UA, User Agent) or terminal constitutes the endpoint of the conversation: It sends or receives SIP requests and responses, which is the end of the multimedia stream. A UA is typically a User Equipment (UE), an application on a terminal or a dedicated hardware device.

The SIP REFER method is defined in RFC 3515. The SIP REFER method provides a mechanism: The sender of the REFER request refers to the receiver whose access to the resource identified in the REFER request. This resource is identified by a Uniform Resource Locator (URL); if the URL is a SIP Uniform Resource Identifier (URI), the recipient of the REFER request will send another SIP request to the SIP URI. UA. In addition, in the normal case, the REFER request also creates a subscription, so that the recipient of the REFER request can notify the sender of the status information and results of the referral.

One application of the SIP REFER method is to implement remote call control functions. Remote call control The system refers to a UA that does not directly participate in the relevant session by sending a REFER request to another UA, instructing the latter to establish, update or terminate the session in which it directly participates. In the operation of remote call control, the UA that sends the REFER request is called a control point, and the UA that receives the REFER request and performs the session operation is called a controlled point. A model of remote call control is shown in Figure 1.

In Figure 1, the entire remote call control process includes the following steps:

Step 101: UA1 (control point) sends a REFER request to UA2 (the controlled point). The request structure is as follows:

REFER sip: ua2@example.com SIP/2.0

To: <sip: ua2@example.com〉

From: <sip: ual @example.com>; tag=dklea

Refer- To: <sip:ua3 @example.com>

Contact: <sip:ual @example.com>

The Refer-To header field of the REFER request contains the SIP URI of UA3. The implicit default operation is the INVITE request, that is, UA1 instructs UA2 to send an INVITE request to UA3 to establish a session. The UA3 is the peer UA of the remote call control session.

Step 102: After receiving the REFER request, the UA2 returns a 202 Accepted response. Step 103: After receiving the REFER request, the UA2 creates a subscription.

Step 104: According to the event subscription/notification (SUBSCRIBE/NOTIFY) framework, UA2 creates a NOTIFY request and sends it to UA1. The NOTIFY request contains not only the Event header with the tag " refer", but also a "message/sipfrag" message body.

Step 105: After receiving the NOTIFY request message, the UA1 returns a 200 OK response. Step 106: The UA2 sends an INVITE request to the UA3 according to the Refer-To header field in the REFER request message, and the structure is as follows:

INVITE sip: ua3@example.com SIP/2.0

To: <sip: ua3@example.com〉

From: <sip: ua2@example.com>; tag=xyz

Call-ID: 123 Contact: <sip: ua2@example.com>

Content-Type: application/sdp m=audio 2200 RTP/AVP 96 97

a=sendrecv

m=video 5050 RTP/AVP 98 99

a=sendrecv

The above INVITE request is a session establishment request, that is, UA2 wants to establish a new session with UA3, and the session includes two media streams, specifically an audio stream and a video stream.

Step 107: The UA3 sends a 200 OK response to the UA2.

Step 108: After receiving the 200 0K response returned by the UA3, the UA2 sends an ACK request to the UA3, indicating that the session is successfully established.

Step 109: The UA2 sends a NOTIFY request to the UA1 again to notify the UA1 of the result of the referral.

In step 110, UA1 returns a 200 0K response to UA2.

At this point, the remote call control method flow ends.

As can be seen from the above example, although UA1 does not directly participate in the session between UA2 and UA3, it remotely controls the session establishment between UA2 and UA3 by sending a REFER request.

The SIP INVITE method is capable of performing two session operations: a session establishment operation and a session update operation, in the above example, a session establishment operation. A session setup operation or session update operation typically involves one or more media stream operations. For example, the session establishment operation in the above example includes two media stream addition operations.

Although the current SIP REFER method can remotely control the establishment, update and termination of sessions, it cannot control the media stream in the remote session, and it cannot realize the increase, decrease, update, switch, and copy of the remote control media stream. Wait for the operation. In this example It can be seen that the session establishment operation performed by the controlled point receiving the REFER request includes two media stream addition operations, but the two media stream operations are determined and completed by the control point according to the session requirements, and are not controlled by Point indicated. The control point only indicates that the controlled point needs to perform a session establishment operation, but does not indicate which media stream operations are included in the session establishment operation. In fact, the current SIP protocol is not able to implement this remote media stream control function.

Although the SIP REFER method can remotely control the establishment, update, and termination of a session, it cannot control the media stream in the remote session. For example, it cannot remotely control the addition, deletion, update, switching, copying, peer switching, and Operations such as peer copy. In addition, a REFER request can only control one session remotely, and cannot control multiple sessions at the same time.

The session that requires remote control is not identified in the REFER request sent by the control point. If the controlled point is originally involved in one or more sessions, when it receives a REFER request from a control point, it does not know whether the REFER request indicates a session establishment operation or an existing one. Perform a session update operation in the session.

The inventor found in the process of invention that the current SIP protocol cannot implement the function of remote media stream control. Summary of the invention

In view of this, the embodiments of the present invention provide a method for implementing remote media stream control, which can implement the function of remote media stream control by using the SIP protocol.

The embodiment of the invention further provides a communication system for realizing remote media stream control, which can implement the function of remote media stream control by using the SIP protocol.

The embodiment of the invention further provides a control point device and a controlled point device in the communication system, which can implement the function of remote media stream control.

To achieve the above objective, the embodiment of the present invention adopts the following technical solutions: A method for implementing remote media stream control, comprising:

The controlled point receives the SIP request message that is sent by the control point and carries the operation indication information, and performs a session operation and/or a media stream operation of the remote indication of the control point according to the operation indication information.

A communication system for implementing remote media stream control, including a control point device and a controlled point device,

The control point device is configured to send, to the controlled point device, a preset SIP request message carrying operation indication information, instructing the controlled point device to perform a required session and a media stream operation; Instructing the ongoing session and media stream operations;

The controlled point device is configured to receive the SIP request message sent by the control point device, and perform corresponding session and media stream operations according to the operation indication information carried in the SIP request message.

A control point device in a communication system, comprising: a remote control unit and an interface unit, wherein the remote control unit is configured to form an operation indication information and a preset SIP request message carrying the operation indication information according to requirements, and Sending the SIP request message to the interface unit; the operation indication information is used to indicate the performed session and the media stream operation;

The interface unit is configured to forward the SIP request message sent by the remote control unit to the controlled point device in the system.

A controlled point device in a communication system, comprising: a first interface unit and a session operation execution unit,

The first interface unit is configured to receive a SIP request message that is sent by the control point device in the system and that carries the operation indication information, and send the request message to the session operation execution unit; the operation indication information is used to indicate that the operation is performed. Session and media stream operations;

The session operation execution unit is configured to perform a corresponding session and media stream operation according to the operation indication information in the SIP request message received by the first interface unit. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a flow chart of the current remote call control.

FIG. 2 is a schematic flowchart of a method for implementing remote media stream control according to an embodiment of the present invention.

FIG. 3 is a schematic structural diagram of a communication system for implementing remote media stream control according to an embodiment of the present invention.

FIG. 4 is a specific flowchart of a method for implementing remote media stream control according to Embodiment 1 of the present invention. FIG. 5 is a schematic diagram of the first possible structure of the operation indication information.

FIG. 6 is a second possible structural diagram of the operation indication information.

Figure 7 is a third possible schematic diagram of the operation indication information.

FIG. 8 is a specific structural diagram of a communication system according to Embodiment 1 of the present invention.

FIG. 9 is a specific flowchart of a method for implementing remote media stream control according to Embodiment 2 of the present invention. FIG. 10 is a specific structural diagram of a communication system according to Embodiment 2 of the present invention. Mode for carrying out the invention

In order to make the objects, technical means and advantages of the present invention more comprehensible, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

FIG. 2 is a schematic flowchart of a method for implementing remote media stream control according to an embodiment of the present invention. As shown in Figure 2, the method includes:

Step 201: The control point sends a SIP request message carrying the operation indication information to the controlled point, and remotely indicates a session operation and/or a media stream operation that the controlled point needs to perform.

Wherein, and / or meaning means: either one of the two, or both. In this step, the session operation and/or media stream operation that needs to be performed refers to: a session operation that needs to be performed, or a media stream operation that needs to be performed, or a session operation and a media stream operation that need to be performed. Step 202: After receiving the SIP request message, the controlled point performs a corresponding session operation and/or media stream operation according to the operation indication information carried therein.

FIG. 3 is a schematic structural diagram of a communication system for implementing remote media stream control according to an embodiment of the present invention. As shown in FIG. 3, the system includes a control point device 310 and a controlled point device 320. The structure of the control point device 310 is the overall structure of the communication system control point device provided by the embodiment of the present invention. The controlled point device 320 is the overall structure diagram of the communication system controlled point device provided by the embodiment of the present invention. It can be seen that the control point device 310 includes a remote control unit 311 and an interface unit 312; the controlled point device 320 includes a first interface unit 321 and a session operation execution unit 322.

In the system, the remote control unit 311 in the control point device 310 is configured to form an operation indication information and a preset SIP request message carrying the operation indication information, and send the SIP request message to the interface unit 312. . The operation indication information is used to indicate the ongoing session and media stream operation.

The interface unit 312 in the control point device 310 is configured to forward the SIP request message sent by the remote control unit 311 to the controlled point device 320.

The first interface unit 321 of the controlled point device 320 is configured to receive the SIP request message that is sent by the control point device 310 and that carries the operation indication information, and sends the request message to the session operation execution unit 322, where the operation indication information is used. Indicates the session and media stream operations.

The session operation execution unit 322 in the controlled point device 320 is configured to perform corresponding session and media stream operations according to the operation indication information in the SIP request message received by the first interface unit 321 .

As can be seen from the above, by operating the indication information, the control point can notify the controlled point to perform the specified session and media stream operations. Specific embodiments of the embodiments of the present invention are described below by way of specific embodiments. In the embodiment of the present invention, the control point may first obtain the session state information of the controlled point, and then form the operation indication information according to the information, or directly send the operation forming operation indication information to be remotely controlled to the controlled point. Specific embodiments of the embodiments of the present invention in the two cases will be respectively described below by means of two embodiments.

Embodiment 1:

In this embodiment, the control point directly sends the remote operation forming operation indication information to be sent to the controlled point. Specifically, FIG. 4 is a specific flowchart of a method for implementing remote media stream control according to Embodiment 1 of the present invention. As shown in Figure 4, the method includes:

Step 401: The control point generates operation indication information according to the remote control operation to be performed. In this embodiment, the content of the generated operation instruction information is also different according to the remote control operation.

In general, the operation indication information may include the following specific information: session indication information, media stream indication information corresponding to the session, an operator corresponding to the media stream, an association indication, and a reason information.

1. Session indication information, used to identify the session being operated, refers to a related indication of a session that the control point wishes to remotely manipulate. This session can be a session that has been attended by the control point, or it can be a session that the control point wants to be newly created by the control point.

The content of the session indication information may include the peer UA identifier and the session identifier. The peer UA identifier refers to the SIP URI of the peer UA participating in the session; the session identifier refers to the identifier of the session different from other sessions. When the control point wants to perform the session establishment operation by the control point, the session indication information includes only the peer UA identifier, and does not include the session identifier. When the control point wants the control point to perform a session update operation, the session indication information includes the session identifier. The session represented by the session identifier is a session that is updated by the control point system. In this case, the session indication information may further include an optional peer UA identifier.

Second, the media stream indication information, used to identify a media stream corresponding to a session, refers to control A related indication of a media stream that is desired to be remotely manipulated.

The content of the media stream indication information includes one or any combination of the following: a media stream identifier, a type of the media stream, and a mode attribute.

The media stream identifier is a mark that distinguishes the media stream from other media streams in the session. The embodiment of the present invention does not specify a specific expression of the media stream identifier, which may be the sequence number of the media stream in the session. , can also be a string describing the media stream, or a number.

The type of media stream is 'media type' defined in the RFC 4566 Session Description Protocol (SDP). The currently defined "media type" includes ' 'audio', "video", "text", "application" and '' message The media stream's schema attributes include the four defined in RFC 4566, which currently include ''sendonly', 'recvonly'', 'sendrecv', and ''inactive''.

When the control point is instructed to perform the media stream switching operation, the media stream copying operation, the media stream peer switching operation, or the media stream peer copy operation, the generated media stream indication information may further carry the source session identifier and the source. Media stream ID. When the media stream switching operation is performed, or the media stream peer switching operation is performed, the generated media stream indication information may carry a handover failure indication.

The source session identifier refers to the session identifier of the original session to which the operated media stream belongs; the source media stream identifier refers to the media stream identifier of the media stream in the original session. The handover failure indication refers to whether the media stream is retained or deleted in the source session of the media stream when the media stream switching operation or the media stream peer switching operation fails.

3. The operator refers to a media stream operation that needs to be performed by the media stream indicated by the media stream indication information.

The operator provided in the embodiment of the present invention includes: an identifier of a media stream adding operation, an identifier of a media stream deleting operation, an identifier of a media stream updating operation, an identifier of a media stream switching operation, an identifier of a media stream copying operation, and a media stream peer end. Identification of switching operations, media stream peer replication Any of the identification of the operation.

4. The association indication is used to indicate the relationship between the multiple sessions, and specifically refers to the relationship between the sessions indicated by the information.

The relationship between sessions can be divided into two types, one is independent and the other is regarded as a logical conversation. The meaning of a logical session is that when the controlled point directly participates in multiple sessions at the same time, these sessions are independent from the perspective of the SIP protocol, because they are established separately through separate SIP dialogs, but the control points put all The media stream contained in the session is considered to be established by a SIP conversation.

5. Reason information, used to carry textual expression information of media stream control.

The above describes the specific information that may be included in the operation instructions. In this step, the operation indication information may include one or more session indication information indicating that one or more sessions perform corresponding operations. Correspondingly, the operation indication information may include one or more media stream indication information for each session, and one operator for each media stream. In this way, the control point can instruct the controlled point to perform multiple session and media stream operations through an operation indication message.

For any session and its corresponding media stream operation, the following rules are followed when forming operational instructions:

When the control point instruction is determined by the control point to determine the media stream operation corresponding to the session, or the command session operation does not include the media stream operation, the formed operation indication information includes the session indication information corresponding to the session, and does not include the corresponding media stream. The indication information and the operator, that is, the corresponding media stream indication information and the operator are empty;

When the control point is instructed by the control point to perform the specified media stream operation, the formed operation indication information includes: session indication information corresponding to the session, media flow indication information corresponding to the session identified by the session indication information, and identifier with the media flow indication information The operator corresponding to the media stream.

Session indication information, media stream indication information, and operators when generating operation indication information The organizational structure includes three types:

The session indication information includes media flow indication information, and the media flow indication information includes an operator. Specifically, the session indication information includes media flow indication information corresponding to the session corresponding to the session indication information, and the media flow indication information is included in the session indication information. The operator corresponding to the media stream identified by the media stream indication information is included.

2. When the operations performed on the media streams corresponding to a session are the same, the session indication information includes media stream indication information and an operator. When the operations performed on the media streams corresponding to a session are different, the session indication information includes the media stream. The indication information, the media stream indication information includes an operator.

The session indication information and the media stream indication information are organized in a parallel manner, and the media stream indication information includes an operator. In this organization structure, the media stream indication information further includes: the media stream indicating the identifier of the session corresponding to the media stream identified by the information.

As described above, when a media stream operation of a session involves a media stream switch, a media stream copy, a media stream peer copy operation, or a media stream peer switch operation, the operation indication information may further include a source session identifier and a source. The media stream identifier; when a media stream operation of a session involves a media stream peer switch or a media stream switch operation, the operation indication information may further include a handover failure indication corresponding to the media stream corresponding to the operator. In fact, the source media stream identifier is usually included in the media stream indication information, and the source session identifier and the handover failure indication are organized in the operation indication information in the same manner as the above-mentioned operator, and may be included in the media stream indication information, or when all When the source session identifier and/or the handover failure indication of the media stream are the same, they are directly included in the session indication information. Certainly, according to the foregoing structure, an organization structure of multiple operation indication information may be evolved. For example, when all the media streams operate the same and the source session identifiers are the same, the session indication information includes the media stream indication information, the operator, and the source session identifier, and the media. The flow indication information includes a handover failure indication and the like.

After being organized in the first manner, a possible structure of the operation indication information is as shown in FIG. That is, the operator, the source session identifier, and the handover failure indication; after being organized in the second manner, a possible structure of the operation indication information is as shown in FIG. 6, that is, all media stream operations, source session identifiers, and handover failure indications are assumed. The same, so the three items are directly included in the session indication information; after being organized in the third manner, a possible structure of the operation indication information is as shown in FIG. 7 , that is, the media flow indication information and the session indication information are organized in parallel, and the operation is performed. Information such as symbols is included in the media stream indication information.

Step 402: The formed operation indication information is carried in the SIP request message and sent to the control point.

In this step, the SIP request message carrying the operation indication information may be: a newly defined SIP method or an extended existing SIP method, such as a SIP REFER method.

The method for carrying the operation indication information in the SIP request message may be: carrying the document for recording the operation indication information in the message body of the SIP request message; or extending the field carrying the operation indication information in the header field of the SIP request message. Wherein, the document description language for recording the operation indication information is an XML language, a text language or a binary language.

When the request for carrying the operation indication information is SIP REFER, then the subscription problem of the REFER request needs to be processed. This embodiment proposes three processing methods.

1. The REFER request can cancel the mechanism of implicit subscription. Specifically, refer to RFC 4488 and set the value of the Refer-Sub header field to "false".

2. The pre-defined session event tag is included in the Event header field of the REFER request, indicating that the control point is to subscribe to the session state information of the controlled point.

3. In the Event header field of the REFER request, a multiple referral event tag is included, indicating that the control point subscribes to the controlled point for the status and result of the referral.

Assume that the REFER request message is carried by the REFER request, and the contents of the transmitted REFER request message are as follows:

REFER sip: recipient@example.com SIP/2.0

<slrea>m

Pp <eote>s : ua @ eae.co</eote>rmilxmlmrm

Gigg <dao cad30cataeotetaabc />illli121lxz rmMHM--- --"--"--"

<sess〇>in

p eae〇eote&c〇to</e^sc>xmlf rm apnrlrm p <sessostsu:et:aas::s: sessost>inli xmlnmifrmxmlninliH-- ---- g < veso.G ecodU8>?xmlrin lTninTT?su- "---- p Cotet:t @eae.conn ID ml 11111xmlm- yppp 5 Cotete: acato/sessostnn Tliininli+xml>-- peeo: <cd:t @ eae.co> Rfr Timl 11111xmlm- ppg;o: < s: C0t02@eae.co> taada Frminr11xmlmffu. pppo: <s:ecet® eae.co> Ti riinxmlm "Independent" means that the relationships between sessions are independent; the <reason> element represents the reason information.

Each <session> element represents a session indication information that is attended by the control point; the <dialog> element indicates the session identifier; the <remote> element indicates the peer UA; each <stream> element represents a media stream indication message in the session. The <id> element represents the media stream identifier; the <type> element indicates the type of the media stream; the <81^18> element indicates the mode attribute of the media stream; <(^ -^&1(3⁄4> element represents the source session identifier; <orig The -id> element represents the source media stream identifier.

The <operation> element specifies the operator: "delete' 'represents the media stream deletion operation; "add" represents the media stream addition operation; "transfer" ' represents the media stream switching operation.

The <preserve> element indicates a handover failure indication, and its value "true" means that the media stream is retained in the source session of the media stream when the media stream switching operation or the media stream peer handover operation fails.

As you can see, the control point wants to manipulate both sessions remotely. The first is the session update operation. The control point requests to update the existing session between the controlled point and UA1, requesting to delete the first media stream and adding a video stream. The second is the session establishment operation, and the control point wants to be A new session is established between the control point and UA3, and the session includes a media stream switching operation.

The value of the Refer-Sub header field of the REFER request is "false", which indicates that the control point cancels the implicit subscription function of the REFER request. The Refer-To header field of the REFER request indicates the location of the "session-list" document in the body of the message.

In addition, it should be noted that the cause information in the operation indication information may be located in the Reason header field defined in RFC 3326, in addition to being located in the operation indication information.

Step 403: The controlled point receives the SIP request message, and extracts the operation indication information. Since the operation indication information may include operations on multiple sessions, it is necessary to perform corresponding operations on the session indicated by each session indication information. The following describes the process of performing session and media stream operations by taking an operation performed on one of the sessions as an example. Step 404, determining the type of session operation to be performed and the peer UA.

In this step, the manner of determining the session operation type may be: if the session indication information includes the session identifier, determining to perform an update operation on the session; if the session indication information does not include the session identifier, determining to perform a session establishment operation.

The manner of determining the peer UA is as follows: The peer UA is identified according to the SIP URI of the peer UA carried in the session indication information, or the peer UA is determined according to the session specified by the session identifier.

Step 405: Perform the corresponding session and media stream operations by interacting with the peer UA according to the session operation type and the operation indication information determined in step 404.

In this step, the INVITE request is first sent to the peer UA according to the type of operation and the operation indication information, and then the peer UA returns a response, and interacts with the control point to complete the corresponding operation.

The way to construct the INVITE request is as follows:

1. Determine the type of the INVITE request based on the type of session operation.

When the session operation type determined in step 404 is a session establishment operation, determining to generate an initial INVITE request;

When the session operation type determined in step 404 is a session update operation, it is determined to generate an INVITE request within the SIP session.

Second, according to the operation indication information, construct an SDP message body in the INVITE request, and form an INVITE request.

When constructing the SDP message body, if the operation indication information includes the media stream indication information and the operator corresponding to the operated session, the SDP message body is constructed according to the media stream indication information and the operator; if the operation indication information does not include and operate The media stream indication information corresponding to the session does not include the media stream operation in the SDP message body, or the controlled point determines the media stream operation information in the SDP message body.

Specifically, when the SDP message body is constructed according to the media stream indication information and the operator, it is controlled. The point generates a corresponding "m=,, and "a=" rows in the SDP message according to the media stream identifier, the type of the media stream, and the mode attribute in the media stream indication information, and the operation type of each of the media streams performing the operation is determined by The relevant operator is determined.

When the operator received by the control point indicates the media stream increase operation, the control point determines that the control point instruction performs the media stream increase operation, and the controlled point sends an INVITE request to the opposite end UA, where the request is requested in the corresponding session. The media stream indicated by the media stream indication information is added. After receiving the INVITE request, the peer UA returns a response, and interacts with the controlled point to implement adding the media stream in the session.

When the operator received by the control point indicates the media stream deletion operation, the control point determines that the control point instruction performs the media stream deletion operation, and the controlled point sends an INVITE request to the opposite end UA, where the request is requested in the corresponding session. The media stream indicated by the media stream indication information is deleted. After receiving the INVITE request, the peer UA returns a response, and interacts with the controlled point to delete the media stream in the session.

When the operator received by the control point indicates the media stream update operation, the control point determines that the control point instruction performs the media stream update operation, and the controlled point sends an INVITE request to the opposite end UA, where the request is requested in the corresponding session. The media stream indicated by the media stream indication information is updated; after receiving the INVITE request, the peer UA returns a response, and interacts with the controlled point to implement updating the media stream in the session.

When the operator received by the control point indicates the media stream switching operation, the control point determines that the control point instruction performs the media stream switching operation, and the controlled point sends an INVITE request to the opposite end UA, where the request is requested in the corresponding session. The specified media stream in the specified session is added. After receiving the INVITE request, the peer UA returns a response and interacts with the controlled point to increase the specified media stream in the specified session in the session. The specified session is another session specified by the source session identifier, and the specified media stream is a media stream specified by the source media stream identifier. And after adding the specified media stream in the corresponding session, further The interaction with the peer UA of the specified session is performed to delete the specified media stream in the specified session. Specifically, the specified media stream may be deleted by using a SIP request message such as an INVITE request or a BYE request.

When the operator received by the control point indicates the media stream copy operation, the control point determines that the control point instruction performs the media stream copy operation, and the controlled point sends an INVITE request to the opposite end UA, where the request is requested in the corresponding session. The specified media stream in the specified session is added. After receiving the INVITE request, the peer UA returns a response and interacts with the controlled point to increase the specified media stream in the specified session in the session. The specified session and the specified media stream have the same meaning as described above.

When the operator received by the control point indicates the media stream peer switching operation, the control point determines that the control point instruction performs the media stream peer switching operation, and the controlled point sends an INVITE request to the opposite end UA, where the request is requested. The specified media stream in the specified session is added in the corresponding session; after receiving the INVITE request, the peer UA returns a response, and interacts with the controlled point to increase the specified media stream in the specified session in the session. In addition, the source session identifier and the source media stream identifier are sent to the peer UA, and may be carried by using the INVITE request or the SDP message body therein. In this way, the peer UA can uniquely determine the media stream to be switched or copied according to the source session identifier and the source media stream identifier. The controlled point may also send the indication of the handover failure in the operation indication information to the peer UA, and may be carried by the INVITE request or the SDP message body therein. In this way, the peer UA that receives the INVITE request can clarify the processing mode when the media stream peer switch fails. The specified session is the session specified by the source session identifier of the peer UA corresponding to the session, and the meaning of the specified media stream is the same as the foregoing.

When the operator received by the control point indicates the media stream peer copy operation, the control point determines that the control point instruction performs the media stream peer copy operation, and the controlled point sends an INVITE request to the opposite end UA, where the request is requested. Add a specified media stream in the specified session in the corresponding session; after receiving the INVITE request, the peer UA returns a response, and is controlled The point interaction implementation adds a specified media stream in the specified session to the session. In addition, the source session identifier and the source media stream identifier may be sent to the peer UA, and may be carried by the INVITE request or the SDP message body therein. In this way, the peer UA can uniquely determine the media stream that is switched or copied according to the source session identifier and the source media stream identifier. The specified session is the session specified by the source session identifier of the peer UA corresponding to the session, and the meaning of the specified media stream is the same as the foregoing.

The above is the process of performing the corresponding session and media stream operations according to the session operation type and the operation indication information.

Next, a specific example is given to the step of sending an INVITE message and performing a corresponding session operation. Assuming that the controlled point receives the SIP REFER request listed in step 402, the INVITE request shown below is sent to the opposite UA (assumed to be UA1) for the content of the first <session> element in the request:

INVITE sip: ual @ example.com SIP/2.0

To: <sip: ual @example.com>; tag=abc

From: <sip: recipient@example.com>; tag=xyz

Call-ID: 123

Contact: <sip: recipient@example.com〉

Content- Type: application/sdp m=audio 0 RTP/AVP 96

m=video 5050 RTP/AVP 98 99

a=sendrecv

In the above request message, the "m=" line and the "a=" line in the SDP message body are constructed based on the two <stream> elements in the first <session> G-:.

After receiving the INVITE request, UA1 returns a 200 OK response; the controlled point sends an ACK request, indicating that the session is successfully updated.

At this point, since the REFER request cancels the implicit subscription, there is no need to return the referral status and result. If the session state information of the controlled point is subscribed when the REFER request is sent, after updating the session, the current session state information of the controlled point after the update needs to be returned to the control. Point. When the control point receives the session status information, it will feed back a 200 OK response.

For the content of the second <session> element of the SIP request message in step 402, the opposite end UA is set to UA3) to send an INVITE request as shown below:

INVITE sip: ua3 @example.com SIP/2.0

To: <sip: ua3@example.com〉

From: <sip: recipient@example.com>; tag=jjjj

Contact: <sip: recipient@example.com〉

Content- Type: application/sdp m=audio 1000 RTP/AVP 96

a=sendrecv

In the above request message, the "m=" line and the "a=" line in the SDP message body are constructed according to the <8^3⁄43111> element in the second h<session>/G" '.

After receiving the INVITE request, the UA3 returns a 200 OK response; the controlled point sends an ACK request to the UA3, indicating that the session is successfully established.

As with the first session operation, if it is necessary to return session status information to the control point, the control point will feed back a 200 OK response.

After that, since the media stream in the new session is switched from the source session between the controlled point and another UA (assumed to be UA2), the controlled point needs to delete the switch between this session and the UA2. Media stream.

If the multiple referral event tag is included in the Event header field in which the REFER request is sent, after the session is updated, a NOTIFY request is returned to the control point, including the execution status of each session operation indicated in the REFER request.

So far, the method for implementing remote media stream control using the SIP protocol provided by the embodiment ends.

The embodiment further provides a communication system for implementing remote media stream control, and a control point device and a controlled point device in the communication system, which can be used to implement the above control method of the remote media stream. FIG. 8 is a specific structural diagram of a communication system according to an embodiment of the present invention. The communication system It is a specific embodiment of the system shown in FIG. As shown in FIG. 8, the system includes: a control point device 310, a controlled point device 320, and a peer UA 330. It can be seen that the system in this embodiment further includes a peer UA 330. The control point device 310 includes a remote control unit 311 and an interface unit 312, which is a specific implementation manner of the control point device 310 in FIG. 3. The controlled point device 320 includes a first interface unit 321 and a session operation execution unit 322, a session. The operation execution unit 322 includes an execution unit 322a and a second interface unit 322b, which is a specific implementation of the controlled point device 320 in FIG.

Specifically, in the communication system, the remote control unit 311 in the control point device 310 is configured to form, according to requirements, operation indication information and a preset SIP request message carrying the operation indication information, and send the SIP request message. To the interface unit 312. The operation indication information is used to indicate the ongoing session and the media stream operation.

In the controlled point device 320, the first interface unit 321 is configured to receive a SIP request message that is sent by the control point device 310 and that carries the operation indication information, and sends the request message to the session operation execution unit 322, where the operation indication information is Used to indicate the ongoing session and media stream operations.

The execution unit 322a in the session operation execution unit 322 is configured to receive the SIP request message sent by the first interface unit 321 and construct an INVITE request according to the operation indication information in the message, and send the request to the second interface unit 322b; It is also used to complete the session and media stream operations according to the information received by the second interface unit 322b.

The second interface unit 322b in the session operation execution unit 322 is configured to receive the INVITE request sent by the execution unit 322a, and send the request to the opposite UA 330, and receive the returned response message and forward it to the second interface unit 322b.

The peer UA 330 is configured to receive the INVITE request sent by the control point device 320, and According to the request, the session and media stream operations are completed by interacting with the controlled point device 320.

It can be seen from the specific implementation manners of the method, the system, and the device in the foregoing embodiment that the control point can be directly sent to the controlled point according to the remote operation to be performed, and the specific instruction is included in the operation indication information. And the media stream operation instruction can not only remotely control the session establishment and update operations of the controlled point, but also directly control the controlled point to perform the specified media stream operation during the session operation. At the same time, since the operation indication information can carry the indication operation of a plurality of sessions in one remote control operation, it is possible to control a plurality of session operations at one time.

Embodiment 2:

In this embodiment, the control point first acquires the session state information of the controlled point, and then sends the operation indication information to the controlled point according to the information. Specifically, FIG. 9 is a specific flowchart of a method for implementing remote media stream control according to Embodiment 2 of the present invention. As shown in FIG. 9, the method includes: Step 901: A control point acquires session state information of a controlled point.

In this step, the manner in which the control point acquires the session state information of the controlled point specifically includes: the control point sends a request message for acquiring the session state information to the controlled point, and after receiving the request message, the controlled point sends the session state information. Give control points.

The control point obtains the session state information of the controlled point may be based on the SIP method, or may be based on a non-SIP method, such as through the Hypertext Transfer Protocol (HTTP), the control point issues an HTTP POST request to the controlled point, and returns from the control point. In the HTTP 200 OK response, when the SIP-based method is used to obtain the session state information of the controlled point, it can choose to use the SUBCRIBE / NOTIFY framework in the SIP protocol. The specific can be:

1. The control point sends a SUBSCRIBE request to the controlled point, including a predefined session event tag in the Event header field of the request, indicating that the control point is to be subscribed to be controlled. Session state information for the point.

In the sent SUBSCRIBE request, the session state information may be described by one or any combination of XML language, SDP language, binary language, and text language description. The content of the session state information includes a peer UA identifier, a session identifier, and media stream state information that includes media stream related information in the session, where the media stream state information includes a media stream identifier, a type of the media stream, and a mode attribute. The meanings and values related to the media stream identification, the type of the media stream, and the mode attribute are the same as those described in the first embodiment. The content of the session state information may also include the SDP message body used in the session in which the control point is currently participating.

2. After receiving the SUBSCRIBE request, the controlled point creates a subscription and carries the session status information in the NOTIFY request and sends it to the control point.

According to the subscription/notification framework, whenever the session attended by the control point changes during the duration of the subscription, it will pass the changed session state information to the control point.

The following example illustrates the above process of obtaining the session state information of the controlled point by using the subscription/notification framework:

A. The control point sends a SUBSCRIBE request to the controlled point. The "session-event" tag in the Event header field of the request represents a session event tag indicating that the control point is to subscribe to the session state information of the controlled point. An example of the requested message is as follows:

SUBSCRIBE sip: recipient@example.com SIP/2.0

To: <sip: recipient@example.com〉

From: <sip: controller@example.com>; tag=ddd

Event: session-event

Accept: application/session-info+xml

B. The controlled point returns a 200 OK response for the SUBSCIRBE request, indicating that it has accepted the request.

C. After the controlled point creates a subscription for the control point, it sends a NOTIFY request to the control point. An example of the requested message is as follows: NOTIFY sip: controller@example.com SIP/2.0

To: <sip: controller@example.com>; tag=ddd

From: <sip: recipient@example.com>; tag=aaa

Event: session-event

Content-type: application/session-info+xml

<?xml version="1.0" encoding="UTF-8"?>

<session-info xmlns="urn:ietf:params:xml:ns: session-info"

Entity="sip: recipient® example.com" >

<remote>sip:ual @example.com</remote>

<type>audio</type>

<status>sendonly</ status>

</stream>

</session>

<remote>sip:ua2 @ example.com</remote>

<type>audio</type>

<status>sendrecv</status>

</stream>

<type>video</type>

<status>sendrecv</status>

</stream>

</session>

</session-info>

In the NOTIFY request, the "session-event" tag in the Event header field represents the session event tag, which indicates that the message body of the NOTIFY request carries the session state information of the controlled point. Session state information is described by a document called "session-info". In this example, the description language for the "session-info" document is the XML language.

In the "session-info" document, each <session> element represents the control point involved a session state information; the <dialog> element indicates the session identifier; < 111 (^> element indicates the peer UA;

A media stream state information; an <id> element represents a media stream identifier; a <type> element indicates a type of media stream; and a <status> element indicates a mode attribute of the media stream. In this example, the value of the media stream identifier is the sequence number of the media stream in the session.

It can be seen that the controlled point in this example is currently participating in two sessions. And UA1

The session between ( sip: ual @ example.com ) contains an audio stream; the session between UA2 ( sip : ua2 @ example.com ) contains an audio stream and a video stream.

D. The control point returns a 200 OK response to the NOTIFY request indicating that it has received the request.

Step 902: The control point forms operation indication information according to the session state information of the controlled point and the remote operation to be performed.

In this step, the state of each session of the controlled point can be known according to the session state information of the currently controlled point, thereby determining the remote operation performed, thereby forming operation indication information. According to the manner of this embodiment, the remote operation can be adjusted according to the session state of the controlled point in real time, so that the implemented remote control is more reasonable.

The process of forming the operation indication information according to the determined remote operation is the same as that in the first embodiment, and details are not described herein again.

Step 903: The formed operation indication information is carried in the SIP request message and sent to the controlled point.

Step 904: The controlled point receives the SIP request message, and extracts the operation indication information. Step 905: Determine the type of session operation to be performed and the peer UA.

Step 906: Construct an INVITE request according to the session operation type and operation indication information determined in step 905, and send the INVITE request to the peer UA, and the peer UA returns a response, and interacts with the controlled point to complete the corresponding session and media stream operations.

The operations of the above steps 903 to 906 are the same as the steps 402 to 405 in the first embodiment. I won't go into details here.

Step 907: The controlled point sends the updated session state information to the control point.

When the session status information is acquired by using the SIP subscription/notification framework in step 901, when the control point subscribes to the controlled point session state information is in an active state, the controlled point sends a NOTIFY request to the control point, carrying the controlled point. Current session state information.

When the session state information is obtained by using other non-SIP methods in step 901, the corresponding message is used to carry the current session state information of the controlled point.

The embodiment further provides a communication system for implementing remote media stream control, and a control point device and a controlled point device in the communication system, which can be used to implement the above control method of the remote media stream. FIG. 10 is a specific structural diagram of a communication system provided by this embodiment. This communication system is yet another specific embodiment of the system shown in FIG. As shown in FIG. 10, the system includes: a control point device 310, a controlled point device 320, and a peer UA 330. It can be seen that the system configuration in this embodiment is the same as that in the first embodiment. The control point device 310 includes a remote control unit 311, an interface unit 312, and a session state information obtaining unit 313, which is another specific implementation of the control point device 310 in FIG. 3. The controlled point device 320 includes a first interface unit 321, a session. The operation execution unit 322 and the session state collection unit 323, the session operation execution unit 322 includes an execution unit 322a and a second interface unit 322b, which is another specific embodiment of the controlled point device 320 in FIG.

Specifically, in the communication system, the session state information obtaining unit 313 in the control point device 310 is configured to acquire session state information of the controlled point and send it to the remote control unit 311.

The remote control unit 311 is configured to form, according to the received session state information, operation indication information and a preset SIP request message carrying the operation indication information, and cancel the SIP request The information is sent to the interface unit 312. The operation indication information is used to indicate the ongoing session and the media stream operation.

In the controlled point device 320, the first interface unit 321 is configured to receive a SIP request message that is sent by the control point device 310 and carry the operation indication information, and send the request message to the session operation execution unit 322. The session state information from the session state information collecting unit 323 is sent to the control point device 310; wherein the operation indication information is used to indicate the ongoing session and media stream operations.

The execution unit 322a in the session operation execution unit 322 is configured to receive the SIP request message sent by the first interface unit 321 and construct an INVITE request according to the operation indication information in the message, and send the request to the second interface unit 322b; It is further configured to complete the session and media stream operations according to the information received by the second interface unit 322b, and send the state of the currently participating session to the session state collection unit 323 after completing the operation.

The session state collection unit 323 is configured to form session state information according to the state of the received session, and forward the message to the first interface unit 321 .

The peer UA 330 is configured to receive the INVITE request sent by the control point device 320, and interact with the controlled point device 320 to complete the session and media stream operations according to the request.

It can be seen from the specific implementation manners of the method, the system and the device in the foregoing embodiment that the control point first acquires the session state information of the controlled point, and based on this, determines the remote operation to be performed, and then forms according to the remote operation. The operation indication information is sent to the controlled point, so that the controlled point completes the specified session and media stream operation. The same as in the first embodiment, in the operation The instruction information includes specific session and media stream operation instructions, which can not only remotely control the session establishment and update operations of the controlled point, but also directly control the controlled point to perform the specified media stream operation during the session operation, and simultaneously Ability to control multiple session operations at once. In addition, further than the first embodiment, the remote operation performed by the embodiment is determined according to the session state information of the controlled point obtained in advance, so that the remote control can be adjusted according to the real-time session state of the controlled point. Operation, improve the rationality of remote control.

As can be seen from the foregoing specific embodiments of the present invention, first, the control point generates operation indication information according to the remote operation performed, and sends a SIP request message carrying the operation indication information to the controlled point, because the operation indication information is recorded. The control point requires the session and the media stream operation performed by the control point. Therefore, after receiving the SIP request message, the control point can confirm the specific session and media stream operation that the control point requests to perform; then, the controlled point follows the operation. Indicates information, performs the corresponding session and media stream operations. In this way, the control point can directly control the specified media stream operation of the controlled point. Further, the operation indication information may carry operation indications for multiple sessions and corresponding media streams, so that the purpose of remotely controlling multiple sessions in one SIP request may be implemented.

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

Claims

Claim

A method for implementing remote media stream control, the method comprising: receiving, by a control point, a SIP request message that is sent by a control point and carrying operation indication information, and executing a remote control point according to the operation indication information Indicated session operations and/or media stream operations.

The method according to claim 1, wherein the operation indication information comprises:

The control point is based on the type of session and session operation to be controlled, and the generated session indication information;

Media stream indication information and operators corresponding to respective session indication information are generated according to media stream operations in respective sessions to be controlled.

The method according to claim 2, wherein the step of the controlled point performing the corresponding session and media stream operations according to the operation indication information comprises:

The control point extracts the operation indication information from the received SIP request, and determines the type of the session operation to be performed and the peer UA of the session according to the session indication information therein;

And determining, according to the session operation type and the operation indication information, the operated session and the media stream, and the operation of each media stream, and interacting with the peer UA to complete the corresponding session and media stream operations.

4. The method of claim 3, wherein

When the session indication information carries the peer user agent UA identifier, which is used to indicate the peer UA that establishes the session by the control point, the controlled point determines to perform a session establishment operation according to the peer UA identifier; and/or,

When the session indication information carries a session identifier for indicating a session updated by the control point, the controlled point determines, according to the session indication information, that the session update operation is to be performed and the The opposite end of the new session UA; and / or,

When the media stream indication information and the operator are empty, the controlled point determines the media stream operation corresponding to the session, or determines that the session operation does not include the media stream operation; and/or, when the media stream indicates the information Carrying one or any combination of the media stream identifier, the type of the media stream, or the mode attribute of the specified media stream, when the operator carries the identifier of the media stream adding operation, the controlled point determines the control point indication to specify The media stream is subjected to an adding operation, and the controlled point interacts with the peer UA of the session identified by the corresponding session indication information, and the media stream indicated by the media stream indication information is added in the session identified by the corresponding session indication information; and / Or,

When the media stream indication information carries one or any combination of the media stream identifier, the type of the media stream, or the mode attribute of the specified media stream, when the identifier of the media stream deletion operation is carried in the operator, the The control point determines that the control point indicates that the specified media stream is deleted, and the controlled point interacts with the opposite UA of the session identified by the corresponding session indication information, and deletes the media flow indication in the session identified by the corresponding session indication information. Media stream identified by the information; and/or,

When the media stream indication information carries one or any combination of the media stream identifier, the type of the media stream, or the mode attribute of the specified media stream, when the identifier of the media stream update operation is carried in the operator, the The control point determines that the control point indicates an update operation on the specified media stream, and the controlled point interacts with the opposite UA of the session identified by the corresponding session indication information, and updates the media flow indication in the session identified by the corresponding session indication information. Media stream identified by the information; and/or,

When the media stream indication information carries the source media stream identifier, the operator carries the identifier of the media stream switching operation, and when the operation indication information carries the source session identifier, the controlled point determines the control point. Instructing to perform a media stream switching operation, interacting with the peer UA of the session identified by the corresponding session indication information, and increasing the session identified by the corresponding session indication information Add the specified media stream in the specified session; determine the peer UA corresponding to the source session according to the source session identifier carried in the operation indication information, and interact with the peer UA to delete the specified media stream in the specified session; and/or ,

When the media stream indication information carries the source media stream identifier, the operator carries the identifier of the media stream copy operation, and when the operation indication information carries the source session identifier, the controlled point determines the control point. Instructing to perform a media stream copy operation, the controlled point interacts with a peer UA of the session identified by the corresponding session indication information, and adds a specified media stream in the specified session in the session identified by the corresponding session indication information; and/or,

When the media stream indication information carries the source media stream identifier, the operator carries the identifier of the media stream peer handover operation, and when the operation indication information carries the source session identifier, the controlled point determines The control point indicates that the media stream peer switching operation is performed, and the controlled point interacts with the opposite UA of the session identified by the corresponding session indication information, and adds the specified media stream in the specified session to the session identified by the corresponding session indication information, and Sending the source session identifier and the source media stream identifier to the peer UA; and/or,

When the media stream indication information and the operator respectively carry the source media stream identifier and the identifier of the media stream peer copy operation, and the operation indication information carries the source session identifier, the controlled point determines the control point indication. Performing a media stream peer-to-peer copy operation, where the controlled point interacts with the peer UA of the session identified by the corresponding session indication information, and adds the specified media stream in the specified session to the session identified by the corresponding session indication information;

The specified session is a session specified by the source session identifier, and the specified media stream is a media stream specified by the source media stream identifier.

The method according to claim 4, wherein when the control point indicates that the media stream switching operation is performed, the operation failure indication further carries a handover failure indication; the controlled point fails according to the handover in the operation indication information Determining, determining whether the specified media stream is retained in the specified session after a media stream switch fails; and/or, When the control point indicates that the media stream peer handover operation is performed, the handover indication indication is further carried in the operation indication information; the control point sends the handover failure indication to the opposite UA of the session identified by the corresponding session indication information.

The method according to claim 1, wherein when the operation indication information includes an operation indication for a plurality of sessions, the operation indication information is further carried: for indicating a plurality of inter-session relationships Associated indication

After receiving the SIP request message by the controlled point, the method further includes: determining, according to the association indication, whether the session represented by each session indication information is regarded as one logical session.

The method according to claim 1, wherein the operation indication information further includes reason information for carrying text expression information controlled by the media stream.

The method according to claim 1, wherein before the control point sends the SIP request message carrying the operation indication information to the controlled point, the method further comprises: the control point acquiring the session state information of the controlled point, And determining the performed remote control operation according to the session state information.

The method according to claim 8, wherein the method for the control point to acquire the session state information of the controlled point is:

The control point sends a request message for acquiring session state information to the controlled point, and after receiving the request message, the control point sends the session state information to the control point.

The method according to claim 9, wherein the method for obtaining the session state information of the controlled point by the control point is specifically: the control point sends a subscription SUBSCRIBE request to the controlled point, and subscribes to the session state of the controlled point. Information

The controlled point receives the SUBSCRIBE request, creates a subscription for the control point, and carries the session state information in the notification NOTIFY request and sends it to the control point;

After performing the corresponding session and media stream operations, the method further includes: when the session state letter, the subscription of the session is active, the control point returns to the controlled point The NOTIFY request, and carries the current session state information of the controlled point.

The method according to claim 9, wherein the request message for acquiring session state information is an HTTP POST request;

The controlled point sends an HTTP 200 OK response carrying session state information to the control point.

The method of claim 1, wherein the SIP request message carries the operation indication information by: carrying a document for recording operation indication information in a message body of the SIP request message; or The extension field in the header field of the SIP request message carries operation indication information.

13. The method according to claim 1, wherein when the SIP request message is a SIP REFER, the control point sets the value of the Refer-Sub header field to "false" to cancel the implicit subscription mechanism;

Alternatively, the control point subscribes to the session state information of the session state in which the control point participates by carrying a preset session event tag in the event in the SIP REFER request;

Alternatively, the control point subscribes to the status and result of the referral by carrying a preset multiple referral event tag in the SIP REFER request, the status and result of the referral including the execution status of each session operation indicated in the REFER request.

14. The method of claim 13 wherein:

When the control point subscribes to the session state information of the session state in which the control point participates, after performing the execution of the corresponding session and the media stream operation, the method further includes: the controlled point sends the current session carrying the controlled point to the control point NOTIFY request for status information;

When the control point subscribes to the status and result of the referral, after performing the corresponding session and media stream operations, the method further includes: the controlled point sends a NOTIFY request carrying the referral status and the result to the control point.

15. A communication system for implementing remote media stream control, comprising a control point device and a controlled point device, wherein The control point device is configured to send, to the controlled point device, a preset SIP request message carrying operation indication information, instructing the controlled point device to perform a required session and a media stream operation; Instructing the ongoing session and media stream operations;

16. The system of claim 15 wherein the control point device comprises: a remote control unit and an interface unit,

The remote control unit is configured to form an operation indication information and a preset SIP request message carrying the operation indication information, and send the SIP request message to the interface unit, where the operation indication information is used to indicate Conversation and media stream operations;

The system according to claim 16, wherein the control point device further comprises a session state information obtaining unit, configured to acquire session state information of the controlled point in the system, and send the session state information to the remote control unit;

The remote control unit is further configured to form operation indication information according to the received session state information.

The system according to claim 15, wherein the controlled point device comprises: a first interface unit and a session operation execution unit,

The session operation execution unit is configured to perform a corresponding session and media stream operation according to the operation indication information in the SIP request message received by the first interface unit.

The system according to claim 18, wherein the session operation execution unit comprises an execution unit and a second interface unit,

The executing unit is configured to receive a SIP request message sent by the first interface unit, and construct an INVITE request according to the operation indication information in the message, and send the request to the second interface unit; Performing session and media stream operations according to the information received by the second interface unit;

The second interface unit is configured to receive an INVITE request sent by the execution unit, send the request, and receive the returned response message to the second interface unit.

The system according to any one of claims 15 to 19, wherein the controlled point device further comprises a session state information collecting unit,

The session operation execution unit is configured to further send the state of the currently participating session to the session state collection unit after performing the corresponding session and the media stream operation;

The session state collection unit is configured to form session state information according to the received state of the session, and forward the session state information to the first interface unit;

The first interface unit is configured to send the session state information to a control point device in the system.

21. A control point device in a communication system, the control point device comprising: a remote control unit and an interface unit,

The control point device according to claim 21, wherein the control point is set The method further includes a session state information obtaining unit, configured to acquire session state information of the controlled point in the system, and send the session state information to the remote control unit;

A controlled point device in a communication system, wherein the controlled point device comprises: a first interface unit and a session operation execution unit,

The controlled point device according to claim 23, wherein the session operation execution unit comprises an execution unit and a second interface unit,

The controlled point device according to claim 23 or 24, wherein the controlled point device further comprises a session state information collecting unit,

The session state collecting unit is configured to form a session according to the received state of the session Status information, and forwarded to the first interface unit;