Interconnection and intercommunication system and method for TETRA communication system and police digital trunking communication system

Abstract

The invention relates to an interconnection and intercommunication system and method for a TETRA communication system and a police digital trunking communication system. The TETRA system interface controller is accessed to the TETRA system through a voice gateway and is used for monitoring and acquiring call signaling and voice data in the TETRA system by taking the switch as a unit; the PDT system interface controller is accessed to the PDT system in a mobile switching center interconnection mode and is used for acquiring monitoring of call signaling and voice data; the PDT voice coding and decoding converter is in communication connection with the PDT system interface controller and is used for realizing mutual conversion between NVCO voice coding and G.711 voice coding; and the interconnection and intercommunication control server is respectively in communication connection with the TETRA system interface controller and the PDT system interface controller and is responsible for controlling and managing interconnection and intercommunication services. Compared with the prior art, the invention realizes interconnection and intercommunication of associated communication services between two special communication systems.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of digital trunking wireless communication, in particular to a method and system for interconnection and intercommunication between different modes of private communication systems. BACKGROUND

[0002] With the rapid development of urban rail transit, there are more and more subway lines in each city, and the wireless communication system network is also more and more complex. In order to facilitate the overall command of the subway line, the demand for cross-system group call is becoming stronger and stronger. At present, the main narrowband system used in urban rail transit is Airbus system and Moto system, which plays an important role in command and dispatch, data transmission and telephone service.

[0003] There are generally interconnection and intercommunication difficulties between different modes of private communication systems, especially in the scene of emergency command and dispatch, because each system operates independently, which often leads to poor communication, information transmission lag, and affects the overall coordination efficiency. With the continuous improvement of the demand for government coordination and communication, the demand for cross-system communication is increasingly urgent. On the basis of the existing running systems 800M TETRA system and PDT system, efficient and stable interconnection and intercommunication become the key link to improve the multi-department coordination operation ability.

[0004] Therefore, there is an urgent need for a method that can realize voice intercommunication, group call, individual call and other basic services between different communication systems, as well as cross-system PTT operation and voice forwarding. SUMMARY

[0005] The purpose of the present application is to solve the problem that different modes of private communication systems cannot realize intercommunication, and the existing intercommunication method is single in function and cannot meet the demand of multi-scene and multi-user intercommunication, and to provide a method and system for interconnection and intercommunication between multiple private communication systems.

[0006] The purpose of the present application can be realized by the following technical solutions: As a first aspect of the present application, a TETRA communication system and police digital trunking communication system interconnection and intercommunication system is provided, which comprises: A TETRA system interface controller accesses the TETRA system through a voice gateway, and is used to listen to and obtain the data of the call signaling and voice in the TETRA system in units of switches; A PDT system interface controller accesses the PDT system in a mobile switching center interconnection mode, and is used to monitor the call signaling and obtain the data of the voice; A PDT voice codec converter is in communication connection with the PDT system interface controller 2, and is used to realize mutual conversion between NVCO voice coding and G.711 voice coding; The interconnection and intercommunication control server is in communication connection with the TETRA system interface controller and the PDT system interface controller respectively, and is responsible for the control and management of the interconnection and intercommunication service.

[0007] As a preferred technical solution, the TETRA system interface controller accesses the TETRA system through a voice gateway, and the specific implementation is as follows: The TETRA system interface controller is connected to the switch of the TETRA system through an IP link; the voice gateway is connected to the same switch through an E1 / T1 or IP link, and a port mirror is configured on the IP switch connecting the switch and the voice gateway, so as to mirror the traffic of the switch and the voice gateway port to the signaling collection port of the TETRA system interface controller.

[0008] As a preferred technical solution, when the TETRA system interface controller monitors the signaling sent by the TETRA system, the call ID, the calling party ISSI / TSSI, the called party ISSI / GSSI, the service type, the allocated voice time slot, and the IP address / port in the signaling are parsed and uploaded to the interconnection and intercommunication control server.

[0009] As a preferred technical solution, the PDT system interface controller accesses the PDT system in a mobile switching center interconnection mode, and the specific implementation is as follows: The E1 port is arranged on the PDT system interface controller and connected to the switching board of the MSC through a cable, and the PRI protocol is adopted to interact with the mobile switching center; The signaling point code of the opposite MSC and the call reference allocation rule are configured on the PDT system interface controller, and the signaling point equivalent to the PDT system interface controller is configured on the MSC side; a trunk group is created and associated to the E1 interface on the PDT system interface controller, and all calls to the TETRA system are sent out using the trunk group; the call from the TETRA system side is mapped by the MSC in the call request in the PRI message as the group call establishment instruction in the PDT system.

[0010] As a preferred technical solution, after the PDT system interface controller receives the call from the TETRA system, the call is identified as a group call listening request, and then a third-party group call establishment request is initiated to the PDT system, and the call from the TETRA system is added as a participant to the third-party group call.

[0011] As a preferred technical solution, the TETRA system call is statically configured on the PDT system interface controller to always belong to a specific monitoring group. When the specific monitoring group is activated, the system automatically calls these TETRA system numbers to pull them into the group call.

[0012] As a preferred technical solution, the interconnection control server is configured with a cross-system communication association relationship and priorities of various types of calls between the TETRA system and the PDT system. When the TETRA system interface controller or the PDT system interface controller receives a communication event in the corresponding communication system, the event information is transmitted to the interconnection control server. The interconnection control server determines whether to trigger cross-system communication. If triggering is needed, the interconnection control server 4 initiates a call request to the opposite system according to the preset binding relationship and priority strategy, and completes the corresponding call control and talk group management.

[0013] As a second aspect of the present application, a TETRA communication system and police digital trunking communication system interconnection method is provided, which is based on the interconnection system as described above, and the steps include: Step 1, initializing system configuration, establishing communication connection between the TETRA communication system and the police digital trunking communication system; Step 2, real-time monitoring of the communication state in the TETRA communication system and the police digital trunking communication system; Step 3, determining whether to trigger cross-system communication, if yes, executing step 4; otherwise, returning to step 2; Step 4, cross-system communication processing according to the preset binding relationship and priority strategy.

[0014] As a preferred technical solution, throughout the communication process, the interface controllers on both sides continuously monitor the link state and talk group state in the systems on both sides, and real-time feedback of the state information to the interconnection control server; when the interface controller on one side monitors the end of the communication event, the interconnection control server will timely notify the other side to release the related resources.

[0015] As a preferred technical solution, the cross-system communication processing according to the preset binding relationship and priority strategy is as follows: When cross-system communication is triggered, the interconnection control server coordinates the PDT system interface controller or the TETRA system interface controller to initiate a call request to the corresponding private communication system, including communication parameters and identity authentication information; the interconnection control server performs identity verification to confirm the legality of the request, and sends a call invitation to the opposite communication system after verification; The interconnection control server creates a voice conference session, and transmits the session information to the opposite system; According to the current call scenario, the virtual agent process realizes voice interconnection and control command operation between the trunking intercom system and the telephone terminal. Set the talk right waiting time, adjust the talk right distribution in multi-person communication; manage the talk right based on the pre-trial role and level, only authorized users can operate the talk right; When the communication ends, the interconnection control server timely informs the other side to release the related resources, closes the voice conference site and updates the communication statistical information.

[0016] Compared with the prior art, the present application has the following beneficial effects: 1) The interconnection method between different systems of the special communication system proposed in the present application solves the problem that different systems cannot communicate in the prior art by respectively accessing the Airbus 800M TETRA system through the TETRA system interface controller 1 and the PDT system through the PDT system interface controller 2, and realizing the signaling interaction and voice dispatching across systems through the interconnection control server 4, realizes real-time communication and information sharing between different systems, and meets diversified communication needs.

[0017] 2) The present application supports the monitoring registration of the interconnection communication group by setting the PDT system interface controller 2 to access the PDT system in the mobile switching center (MSC) interconnection mode, realizes the monitoring of the call signaling and the acquisition of the voice data in the PDT system, supports participating in the communication in the PDT system as one party of the call, and can also initiate a call in the PDT system and talk with other terminals and realize call control as a communication initiator. And the real-time dynamic conversion of the NVOC voice coding of the PDT system and the G.711 voice coding of the Airbus 800M TETRA system is realized, ensuring that voice data in different coding formats can be efficiently transmitted in the two systems.

[0018] 3) In the present application, the signaling monitoring of the TETRA system interface controller 1 is performed in real time for the signaling of the switch unit, and the voice gateway device of the Airbus TETRA system is used as an access point to realize the monitoring and forwarding of the voice channel in the TETRA system; at the same time, dynamic resource loading and flexible allocation of the voice channel are supported, ensuring that the resource occupation can be dynamically adjusted according to the actual needs when multiple groups of concurrent communication are performed; as a communication initiator, a call can be initiated in the Airbus 800M system and communication with other terminals and call control can be realized. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The present application is intended for the interconnection and intercommunication system of the TETRA communication system and the police digital trunking communication system.

[0020] Figure 2 The present application is intended for the interconnection and intercommunication method flow chart of the TETRA communication system and the police digital trunking communication system. DETAILED DESCRIPTION

[0021] The present application will be described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments are implemented on the premise of the technical solutions of the present application, and detailed implementation modes and specific operation processes are given, but the protection scope of the present application is not limited to the following embodiments.

[0022] Embodiment 1 The present application proposes a cross-system communication solution for realizing interconnection and intercommunication of associated communication services between two relatively independent systems, namely, the Airbus 800M TETRA private communication system and the police digital trunking (PDT) communication system. Figure 1 As shown in the figure, in order to realize interconnection and intercommunication between the Airbus 800M TETRA private communication system (hereinafter referred to as the TETRA system) and the police digital trunking communication system (hereinafter referred to as the PDT system), the system includes the following parts: a TETRA system interface controller 1, a PDT system interface controller 2, a PDT voice codec converter 3, and an interconnection and intercommunication control server 4.

[0023] The TETRA system interface controller 1 accesses the Airbus 800M TETRA system and is used for monitoring call signaling and obtaining voice data; the PDT system interface controller 2 accesses the PDT system and is used for monitoring call signaling and obtaining voice data; the PDT voice codec converter 3 is used for mutual conversion between the NVCO voice coding specific to the PDT system and the more general G.711 voice coding; and the interconnection and intercommunication control server 4 is responsible for control and management of the overall interconnection and intercommunication service, including call establishment, disconnection, voice data forwarding, and other functions, to ensure the stability and real-time performance of communication between the TETRA system and the PDT system. By deploying corresponding system interface controllers on each relatively independent communication system side, access to each private communication system is realized; and unified scheduling and signaling interaction are performed through the interconnection and intercommunication control server 4 to realize voice intercommunication and collaborative control between different systems. This solution not only supports basic services such as group call and individual call, but also realizes PTT operation and voice forwarding across systems, meeting the scheduling needs in multiple scenarios. At the same time, the system has voice codec conversion function, ensuring efficient transmission and restoration of voice data in different coding formats in the two systems, and guaranteeing communication quality and real-time performance.

[0024] Firstly, the TETRA system interface controller 1 is connected with the Airbus 800M TETRA system through a voice gateway, and real-time monitoring of signaling in units of switches is performed to complete monitoring of TETRA system internal call signaling and acquisition of voice data. Specifically, the TETRA system interface controller 1 is connected to a switch (DXT) of the Airbus 800M TETRA system through an IP link. The voice gateway is located between the switch (DXT) of the TETRA system and an external network, and is connected to the same switch DXT through an E1 / T1 or IP link. On an IP switch connecting the switch DXT and the voice gateway, a port mirror is configured. The traffic of the DXT and the voice gateway port is mirrored to a signaling collection port of the TETRA system interface controller 1. When the TETRA system interface controller 1 monitors the TETRA signaling, the call ID, the calling party ISSI / TSSI, the called party ISSI / GSSI, the service type (individual call, group call), the allocated voice time slot, and the IP address / port are parsed and uploaded to the interconnection control server 4.

[0025] In another aspect, the PDT system interface controller 2 is connected to the PDT system in a mobile switching center (MSC) interconnection mode, completes relevant registration and monitoring group registration, to realize real-time monitoring of PDT system call signaling and acquisition of voice data. Specifically, the E1 port is provided on the PDT system interface controller 2, and is connected to the switching board of the MSC through a cable, and the PRI protocol is used to interact with the mobile switching center. The signaling point code of the opposite MSC and the call reference allocation rule are configured on the PDT system interface controller 2, and the signaling point equivalent to the PDT system interface controller 2 also needs to be configured on the MSC side. A trunk group is created and associated to the physical E1 interface on the PDT system interface controller 2, and all calls to the TETRA system are sent out using the trunk group. The call from the TETRA system side is mapped to a group call establishment instruction in the PDT system by the MSC from the call request in the PRI message. After receiving the call of the TETRA system, the PDT system interface controller 2 identifies it as a group call monitoring request, and then initiates a third-party group call establishment request to the PDT system, and adds the call of the TETRA system as a participant to the third-party group call. Optionally, the TETRA system call is statically configured on the PDT system interface controller 2 to always belong to a specific monitoring group. When the specific monitoring group is activated, the system automatically calls these TETRA system numbers to pull them into the group call.

[0026] The interconnection and interworking control server 4 establishes the cross-system communication association and sets the priority of various types of calls. Then, once the TETRA system interface controller 1 side monitors that there is a communication event in the Airbus 800M TETRA system, the TETRA system interface controller 1 transmits the event information to the interconnection and interworking control server 4, which judges whether cross-system communication needs to be triggered and processes according to the preset binding relationship and priority strategy; if it needs to be triggered, the interconnection and interworking control server 4 coordinates the PDT system interface controller 2 to initiate a call request to the PDT system, and completes the corresponding call control and right management. Conversely, if the PDT system interface controller 2 side monitors that there is a communication event in the PDT system, the PDT system interface controller 2 also processes similarly. At the same time, in the process of voice transmission, the real-time conversion of voice coding is realized through the PDT voice coding and decoding conversion module 3, ensuring the seamless transmission of voice data between the two systems; during the entire communication process, the system interface controllers on both sides continuously monitor the link (call) state and right transfer state in the systems on both sides, and real-time feedback of the state information to the interconnection and interworking control server 4 ensures the stability and reliability of cross-system communication. When the system interface controller on one side monitors that the communication event is over, the interconnection and interworking control server 4 will promptly notify the other side to release the relevant resources.

[0027] Embodiment 2 As another embodiment of the present application, the embodiment also provides an interconnection and interworking method based on the system described in Embodiment 1, as shown in the following steps: Figure 2 The specific steps include: Step 1, initializing system configuration, establishing communication connection between the TETRA communication system and the police digital trunking communication system; Step 2, real-time monitoring of the communication state in the TETRA communication system and the police digital trunking communication system; Step 3, judging whether cross-system communication needs to be triggered, if yes, executing Step 4; otherwise, returning to Step 2; Step 4, processing cross-system communication according to the preset binding relationship and priority strategy.

[0028] Specifically, the communication connection in Step 1 is established as follows: The TETRA system interface controller 1 is connected with the Airbus 800M TETRA system through a voice gateway, G.711 coding mode is adopted for voice transmission, and a switch is used for real-time monitoring of signaling. In this way, high-quality transmission of voice data is ensured, and real-time monitoring and fault warning of system state are realized.

[0029] The PDT system interface controller 2 is connected to the PDT system in the mode of mobile switching center (MSC) interconnection, and the SVR coding mode is used for voice transmission, and relevant registration and monitoring group registration are completed. The selection of this coding mode ensures efficient compression and transmission of voice data and reduces the occupation of network resources.

[0030] The cross-system communication association is established in the interconnection and interworking control server 4, and the relevant priority of the communication type is set, so as to ensure that the system can process train dispatching related call signaling according to the priority, thereby improving the overall efficiency and reliability of the system. The PDT voice coding and decoding conversion module 3 is configured to realize the mutual conversion between the NVOC coding used by the PDT system and the G.711 voice coding used by the TETRA system.

[0031] In step 2, the TETRA system interface controller 1 monitors whether there is a communication event in the Airbus 800M TETRA system in real time, and the PDT system interface controller 2 monitors whether there is a communication event in the PDT system in real time. When the system interface controller on either side detects a communication event, step 3 is executed. The communication event includes group call, individual call, PTT operation, etc., and the relevant information is recorded immediately when the communication event is detected.

[0032] Step 3 judges whether cross-system communication needs to be triggered, which is as follows: When the TETRA system interface controller 1 detects that there is a communication event in the Airbus 800M TETRA system, the event information including the communication type, called number, calling number, etc. is transmitted to the interconnection and interworking control server 4. The server is responsible for preliminary processing and verification of these information. Specifically, the server will perform format checking on the received information to ensure the integrity and accuracy of the data, and further processing after verification.

[0033] When the PDT system interface controller 2 detects that there is a communication event in the PDT system, the PDT system confirms the information of the event, identity verification and authority check to ensure the legality and security of the communication request. In addition, the PDT system also maintains an event log to record all communication events and corresponding processing results for subsequent analysis and optimization.

[0034] The interconnection and interworking control server 4 judges whether cross-system communication needs to be triggered according to the preset binding relationship and priority strategy. The server determines the relevant information of the communication event by querying its internal database, and makes decisions based on the preset rules. For example, the server may decide whether to start the cross-system communication process according to the communication type, timestamp or other factors. In addition, the server also considers the personal preferences and historical data of the user to optimize the communication path and select the optimal communication mode.

[0035] In step 4, the cross-system communication processing flow is as follows according to the preset binding relationship and priority strategy: Step 401: When cross-system communication needs to be triggered, the interconnection control server 4 coordinates the PDT system interface controller 2 or the TETRA system interface controller 1 to initiate a call request to the corresponding private communication system. The request contains necessary communication parameters and identity authentication information to ensure the security and reliability of the communication. At this time, the interconnection control server 4 will perform identity verification to confirm the legality of the request, and after verification, it will send a call invitation to the opposite communication system to prevent unauthorized access.

[0036] Step 402: Create a voice conference session through the interconnection control server 4 and pass the session information to the opposite system. The server is responsible for managing all voice conference resources and dynamically adjusting resource allocation when needed. In addition, the server will adjust the number of times and time intervals of sending conference invitations according to the response of the conference invitation to improve the response rate of the conference invitation.

[0037] Step 403: According to the current call scenario, the virtual agent process realizes voice interworking and control command operation between the cluster intercom system and the telephone terminal, such as PTT switch control, talk permission application, etc. The process ensures that in complex communication scenarios, the call permission and participant role can be flexibly adjusted. In addition, the process also monitors the call quality in real time and automatically adjusts the encoding and decoding settings when necessary to optimize the clarity and stability of voice transmission.

[0038] Step 404: Implement the control function of applying for talk permission in cluster communication on the phone and mobile phone, and set the talk permission waiting time to 5 seconds. In multi-person communication, the talk permission distribution can be flexibly adjusted according to needs. In addition, talk permission management is also based on pre-set roles and levels to ensure that only authorized users can perform talk permission operations in different scenarios. This function realizes fine-grained permission management through access control list (ACL) to prevent illegal operations by unauthorized users.

[0039] Step 405: When the communication ends, the interconnection control server 4 timely notifies the other side to release related resources, including voice resources, signaling resources, etc. Close the voice conference session. Update the communication statistical information.

[0040] The above describes the preferred embodiments of the present application in detail. It should be understood that those skilled in the art can make many modifications and changes without creative labor according to the concept of the present application. Therefore, any technical solution obtained by logical analysis, reasoning, or limited experiment based on the prior art according to the concept of the present application shall be within the protection scope determined by the claims.

Claims

1. A TETRA communication system and police digital trunking communication system interconnection and intercommunication system, characterized in that, The system comprises: a TETRA system interface controller (1) which accesses the TETRA system through a voice gateway and is used to acquire data of call signaling and voice in the TETRA system in a switch unit; a PDT system interface controller (2) which accesses the PDT system in a mobile switching center interconnection mode and is used to acquire data of call signaling and voice; a PDT voice codec converter (3) which is in communication connection with the PDT system interface controller 2 and is used to realize mutual conversion between NVCO voice coding and G.711 voice coding; an interconnection and intercommunication control server (4) which is in communication connection with the TETRA system interface controller (1) and the PDT system interface controller (2) respectively and is responsible for control and management of interconnection and intercommunication services.

2. The interconnection system of a TETRA communication system and a police digital trunking communication system according to claim 1, characterized in that, The TETRA system interface controller (1) accesses the TETRA system through a voice gateway, and the specific process is as follows: The TETRA system interface controller (1) is connected to a switch of the TETRA system through an IP link; the voice gateway is connected to the same switch through an E1 / T1 or IP link; and a port mirror is configured on an IP switch connecting the switch and the voice gateway, so as to mirror the traffic of the switch and the voice gateway to a signaling acquisition port of the TETRA system interface controller (1).

3. The interconnection system of a TETRA communication system and a police digital trunking communication system according to claim 1, characterized in that, When the TETRA system interface controller (1) monitors the signaling sent by the TETRA system, the call ID, the calling party ISSI / TSSI, the called party ISSI / GSSI, the service type, the allocated voice time slot and the IP address / port in the signaling are parsed and uploaded to the interconnection and intercommunication control server (4).

4. The interconnection system of a TETRA communication system and a police digital trunking communication system according to claim 1, characterized in that, The PDT system interface controller (2) accesses the PDT system in a mobile switching center interconnection mode, and the specific process is as follows: An E1 port is arranged on the PDT system interface controller (2) and connected to a switching board of the MSC through a cable, and the PRI protocol is adopted to communicate with the mobile switching center; The signaling point code of the opposite MSC and the call reference allocation rule are configured on the PDT system interface controller (2), and a signaling point equivalent to the PDT system interface controller (2) is configured on the MSC side; a trunk group is created and associated to the E1 port on the PDT system interface controller (2), and all calls to the TETRA system are sent out by using the trunk group; the call from the TETRA system side is mapped as a group call establishment instruction in the PDT system by the MSC from the call request in the PRI message.

5. The interconnection system of a TETRA communication system and a police digital trunking communication system according to claim 4, characterized in that, After the PDT system interface controller (2) receives the call of the TETRA system, the call is identified as a group call monitoring request, and then a third-party group call establishment request is initiated to the PDT system, and the call of the TETRA system is added as a participant to the third-party group call.

6. The interconnection system of a TETRA communication system and a police digital trunking communication system according to claim 5, characterized in that, The PDT system interface controller (2) is statically configured that the TETRA system call always belongs to a specific monitoring group. When the specific monitoring group is activated, the system automatically calls these TETRA system numbers and pulls them into the group call.

7. The interconnection system of a TETRA communication system and a police digital trunking communication system according to claim 1, characterized in that, The interconnection control server (4) has a cross-system communication association relationship and is configured with the priority of various types of calls between the TETRA system and the PDT system; When the TETRA system interface controller (1) or the PDT system interface controller (2) receives a communication event in the corresponding communication system, the event information is transmitted to the interconnection control server (4); The interconnection control server (4) determines whether to trigger cross-system communication; If it needs to be triggered, the interconnection control server 4 initiates a call request to the opposite system according to the preset binding relationship and priority strategy, and completes the corresponding call control and talk right management.

8. A method for interworking a TETRA communication system and a P25 communication system, characterized in that, The method is based on the interconnection system as claimed in any one of claims 1-7, and the steps include: Step 1, initialize system configuration, establish communication connection between TETRA communication system and police digital trunking communication system; Step 2, real-time monitoring of the communication state in the TETRA communication system and the police digital trunking communication system; Step 3, determine whether to trigger cross-system communication, if yes, execute step 4; otherwise, return to step 2; Step 4, cross-system communication processing according to the preset binding relationship and priority strategy.

9. The method for interworking TETRA communication system and police digital trunking communication system according to claim 8, characterized in that, In the whole communication process, the interface controllers on both sides continuously monitor the link state and talk right state in the systems on both sides, and real-time feedback the state information to the interconnection control server; when the interface controller on one side monitors the end of the communication event, the interconnection control server will timely notify the other side to release the related resources.

10. The method for interworking TETRA communication system and police digital trunking communication system according to claim 9, characterized in that, The cross-system communication processing according to the preset binding relationship and priority strategy is as follows: When cross-system communication is triggered, the interconnection control server (4) coordinates the PDT system interface controller (2) or the TETRA system interface controller (1) to initiate a call request to the corresponding private communication system, including communication parameters and identity authentication information; the interconnection control server (4) performs identity verification to confirm the legality of the request, and sends a call invitation to the opposite communication system after verification; Create a voice conference session through the interconnection control server (4), and pass the session information to the opposite system; According to the current call scenario, realize voice interconnection and control command operation between the trunking intercom system and the telephone terminal through the virtual agent process; Set the talk right waiting time, adjust the talk right allocation in multi-person communication; based on the preset roles and levels, only authorized users can perform talk right operation; When the communication ends, the interconnection control server (4) timely notifies the other side to release the related resources, closes the voice conference session and updates the communication statistical information.

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