KR100198930B1 - Conference phoning service - Google Patents

Abstract

The present invention relates to a method for processing a digital conference call service for a subscriber who satisfies a user-network connection signaling scheme in an all-electronic exchange, and is applicable to a private exchange satisfying an ISDN subscriber-network interface, (PSTN), it is possible to realize the conference call function of the digital subscriber without modification of the existing network, and it is designed based on the recommendation of the International Standard Specification (CCITT), so that the ISDN subscriber- The present invention can be easily applied to an electronic exchange satisfying Since the present invention implements the function as one independent block, the independence between the other functions and the blocks to be performed is maintained, thereby improving the efficiency of the call processing function and improving the modularity of the software system. In addition, when the conference call function is performed in the existing PSTN network, the conference call function subscribers can not know whether the call is correctly connected or released when the conference call is completed after the conference call is completed. However, in the ISDN network, since the service success message is provided using the LCD of the subscriber terminal, it is possible to visually check the subscriber's terminal, and when the conference call service fails, the subscriber can act actively using the LCD of the terminal, The quality of the call service can be further improved.

Description

How to handle digital conference call service in all electronic exchanges

FIG. 1 is a schematic structural view of a total electronic exchanger as a distributed control system to which the present invention is applied; FIG.

FIG. 2 also shows a processing procedure of a basic call in which a digital subscriber A is originated and processed in an electronic exchanger.

Figure 3 shows the processing procedure inside the network when making a Hold (A) subscriber and an A-B (CR1) subscriber in a call (B) on hold.

FIG. 4 is a process diagram illustrating the creation and disappearance of a processor within a network until a call is placed on hold during a call.

FIG. 5 shows a transition process of the control process in the network until the subscriber A (CR2) calls a new incoming call and tries to make a conference call in the existing A-B (CR1) subscriber.

FIG. 6 also shows the processing procedure after CR1 (call reference number 1) is in a pending state and CR2 (call reference number 2) uses a conference call function request code to attempt a call for calling party A (CR2) during a call.

FIG. 7 is a flow chart of a hold status processing of called subscribers for a conference call during a three-way call.

FIG. 8 is a processing flow diagram of a method for releasing a final calling subscriber using a function request code [* 14 *] during a conference call.

FIG. 9 is a state transition diagram based on the implementation of the software of the DMULC, which is a conference call service processing block according to the present invention; FIG.

DESCRIPTION OF THE REFERENCE NUMERALS

ASP: Matching exchange control processor ASS: Matching exchange subsystem

ASS-S: subscriber registration exchange subsystem

ASS-I: ISDN subscriber exchange subsystem - Subscriber

ASS-T: Relay call adaptation exchange subsystem CCS: Common line signal subsystem

DCC: Digital subscriber line mode control block

DSSC: digital subscriber service control block

DMULC: Digital Subscriber Multi-currency INP: Internal Network Processor

INS: Network Subsystem NTP: Number Translation Processor

The present invention relates to a method of processing a digital conference call service for a subscriber satisfying a user-network connection signaling scheme in an electronic exchanger (basic matching interest, a primary municipality limited joint, a basic access multiple subscriber).

Up to now, the Public Switched Telephone Network (PSTN) has provided a conference call service based on an analog connection method for telephone users. In the PSTN, a signal transmission channel between a subscriber and a network is not separately provided, so that a limited service can be provided only by an audible sound through an information transmission channel. A public switched telephone network (PSTN) and an information communication network (ISDN) Since the connection standard for the exchange period is different, the conventional technique is not applicable to ISDN. In addition, since the conventional technology is provided to subscribers only by using audible sounds, it is impossible to provide a service to data mode terminals other than the telephone, and a new technique is required to provide services to all ISDN access terminals such as telephone and data.

The present invention relates to an electronic exchanger which, in an environment of an electronic exchange, accommodates five subscribers to a digital subscriber who satisfies an ISDN user-network access signaling method and is capable of accepting a functional protocol, and switches another subscriber from a busy state to a conference call And a method of processing a digital conference call service.

The conference call function is provided in the existing analog public switched telephone network (PSTN), and the conventional conference call service satisfies the connection standard with the ISDN subscriber-network when the commercialized technology or the existing network is absorbed and the single network ISDN is established. The service could not be provided in ISDN.

The conference call service provided by the PSTN is a service that should be provided in ISDN as a matter of course. It can accommodate the functional protocol that satisfies the connection standard with the ISDN subscriber network and standardizes the control method of the network and the method of using the supplementary service. There is a need for an implementation method of the conference call function of the new technology.

Therefore, according to the present invention, the call originated or received by the ISDN subscriber is held, and another subscriber is sequentially called to transmit all of the subscribers connected in order to attempt the six-party conference call in the three-, four- or five- The CMX is connected to the CMX in order to attempt a conference call while the other subscriber is on the pending state and the CMX is connected to the CMX in order to attempt the conference call. Thus, the previous work for realizing the service interworking with the existing PSTN network And to provide a method of processing a subscriber conference call service in an exchange.

According to an aspect of the present invention, there is provided a digital conference call processing block that receives a digital conference call service request in an outmost process for controlling a conference call service, searches contents of a database, Step 1: The digital conference call processing block receiving the digital conference call service as an outmost process controlling the conference call service generates a child process dedicated to the control of the conference call service, B, C, D, E, and F). The second process is to stop the processes of the subscriber A, B, C, D, Calculates the various data for communicating with the processor controlling the subscriber B, C, D, and E, And requests the control process to the subscriber A so as to connect the subscriber A and the subscriber B, C, D, E, and F, and stops and returns the subscriber's process when the subscriber requests the disassociation. Step 3: Process) requests the service transition by the control process of the pending subscriber, and if there is no service transition response, the subscriber in the call passes control to the basic call processing block in the busy state and returns. Step 4: The child process is suspended A fifth step of receiving a service transition response by a control process of subscribers, receiving a service transition response, requesting a service transition from a subscriber F in a call and receiving a service control transition response, : After clearing the CMX of the last called party using the special service code during the conference call, Step 6: During the conference call, when the function holder releases the call, all the called party releases the call and releases the conference equipment, and the own process is canceled and returned. Step 7: If the called subscriber requests the call release, the child process releases the CMX, and the child process remains in the busy state. Step 8: If the called subscriber is a subscriber, release the CMX, and then transmit the B channel Reallocates the call to the subscriber B, requests resumption to the subscriber B, makes a transition request to the base call processing block and receives a control transition confirmation notification, and takes over control to the base call processing block after connection of the two-way call and returns.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic structural view of an electronic switching system to which the present invention is applied.

And is composed of three subsystems: an access switching subsystem (ASS), an interconnection network subsystem (INS), and a central control subsystem (CCS), to which the present invention is applied.

The ASS includes a subscriber and a trunk interface, a time switch, various signal devices, and a packet handler, and performs most call processing functions and self-functions, and has a systematic horizontal distribution structure.

ASS can be connected through a maximum of 60 ASSs, and there is one ASS in the source state. However, in the application stage, ASS_S (Subscriber), ASS_I (ISDN Subscriber), ASS_T (Trunk) and ASS_7 (No. 7 Signaling System) In the ASS_S, ASP (Access Switching Processor) is called the call processing function for the subscriber accommodated in the exchange and the ISDN subscriber. In the ASS_T, the intervening circuit call processing function is ASP. In the ASS_7, The ASP and the Signaling Message Handling Processor (SMHP) perform the functions of a Message Transfer Part (MTP) and a Signaling Connection Control Part (SCCP). In the INS, the Number Translation Processor (NTP) and the Interconnection Network Processor (INP) perform the number translation function, the routing control function, and the space division switch control function, which are common call processing functions required in each ASS, Function The data channel connection function with other systems is performed.

An object to implement digital (ISDN) subscriber conference call function in an electronic exchange having such a hardware structure is subsystem ASS.

A digital multimedia conference call processing software block DMULLC (Digital Mulitic way Call) is installed in ASS to interact with existing basic call service blocks to provide digital conference call service. The time when the digital conference call function is implemented is described in the basic call processing process since the existing call is held and the conference call is made while the new subscriber is in a call state.

The software blocks required for the digital base station call processing are DCC (Digital Circuit Control), UPC (User Part Control), NTR (Number Translation), RCO (Route COntrol) and Global Service Control (GSC) There is a block.

The NTR is in the INS subsystem and the remaining blocks are in the ASS subsystem. Requests and Connect messages sent from the digital subscriber are transmitted to the DCC block. The DCC block examines each message and processes it according to the message content (request).

2 is a processing procedure diagram of a basic call in which the digital subscriber A (call reference number 1) is originated and processed in the electronic exchange.

The call processing procedure starts when the exchange receives a SETUP message from the user (Sub-a) side in a null call state. In the Enbloc transmission, the call setup message includes all the information on the called subscriber included in the SETUP message, and sends a notification to the subscriber to analyze the received information. However, in the Ovwrlap transmission method, there is no information on the called subscriber in the call setup message, or only a part of information is provided and a dial tone is provided. In this case, the exchange sends a Setup Acknowledge message to the subscriber to receive the required subscriber information. At this time, additional information is received using an information message. The exchange refers to the channel identification information in the call setup message received from the user side and acquires one of the available B channels according to the B channel selection.

We consider the basic call processing procedure (Enbloc) method (see CCITT Recommendation Q.931) as a premise.

If the B channel is secured and the call can be continued, a CALL PROCEEDING message is transmitted to the calling subscriber. Upon receipt of the information element signal by the DCC-a serving as the calling subscriber, it confirms whether the requested call is speech, obtains the called number, performs a station number translation request (PfxTRANSrq) to the NTR block, Receive an OutgoingCallRP. Then, the originating DCC-a block transmits an incoming call number translation request (CdNoTransRQ) to the NTR block, and the NTR block performs an incoming call occupation request (DigCdSubsSzRQ) to the incoming DCC-b block. Then, the calling DCC-a block transmits the calling information request (DigCgInfoRQ) to the calling DCC-a block, and connects the voice switch (time switch, space switch) DigCgInfoRQ)).

The called BCC-b block informed of the origination information sends a SETUP message to the incoming digital subscriber (sud-B) to notify the call reception.

The incoming DCC-b block then sends an ALERT and CONNECT message from the incoming digital subscriber to the calling DCC-a block and the call goes into ACTIVE state. Call release in the busy state is divided into call release by user and call release by exchange. The call cancellation by the subscriber can cancel any of the incoming and outgoing digital subscribers. The DCC block received from the subscriber is released to the relative DCC block (DigCgRelRp, DigCdRelRp) to release the call. Is canceled when a release message is simultaneously transmitted to the subscriber side.

FIG. 3 is a processing procedure diagram of a network when a calling subscriber and a called subscriber hold a subscriber in a call hold state.

DSSC-a is an additional service processing block inherited from control of originating subscriber A from DCC-a, and DSSC-b (CR1) represents an additional service processing block inherited from control of called subscriber B from DCC-b.

First, when the digital calling subscriber A presses a hold key, it receives a HoldIC message from the calling subscriber DCC-a and transmits a Hold Request message (HoldRQCS) to a DSSC (Digital Subscriber Service Control) Message and the DCC Process itself is destroyed. The DSSC-a that receives the supplementary service transition request message takes over the process identification number of the originating DCC-a and transmits the originating DCC-a using the primitive of the concurrent real time operating system (CROS) (STOP) and creates its own child process (control).

The newly generated originating DSSC-a (CR1) block transmits a service transition request (SubsSvcRQ) message to the incoming DCC-b block, and the DCC-b block transmits an additional service transition request (DigSubsSvcCtrlRQ) message to the incoming DSSC-b. The incoming DSSC-b will terminate the DCC-b block in the same manner as originating and take over control to the incoming DSSC-b block. The newly created DSSC-b at the called party sends a service transition acknowledgment message (SubsSvcACK) to the originating DSSC-a (CR1) block and the originating DSSC-a (CR1) And transmits a HoldToneConnRQ message and a subscriber service notification (SubsSvcRP) to the DSSC-b block.

When receiving the hold tone connection request (HoldToneConnRQ), the called DSSC-b releases the existing time switch and connects the HoldTone to the calling subscriber so that DSSC, which is an additional service control block, is connected between the digital subscriber AB It becomes a holding state to be controlled.

As described above, the call hold method of the second and third figures is basically designed with the same concept as that provided by the PSTN, but unlike the PSTN network which uses only the keypad protocol, the call hold method using the Functional Protocol It is now possible to hold the basic call using the Hold Key.

In addition, as the terminal becomes intelligent, it becomes possible to manage the call reference number of 2B + D type, and thus the implementation method in the network in a new concept different from the PSTN is described from FIG.

FIG. 4 schematically illustrates a process in a network responsible for subscriber control, which is a simplified representation of FIG. 2 and FIG. 3;

In case of normal call between A-B (CR1) subscribers, DCC controls them, and when subscriber B holds the call, the control process in the network transfers control from DCC to DSSC block and DCC block disappears.

FIG. 5 shows a process from the point of view of process creation in the network until a subscriber A (CR2) attempts a conference call by calling a new incoming call while the existing A-b (CR1) subscriber is in a pending state.

Since the subscriber A (CR2) sends a SETUP message to the network to call the new called subscriber C, the terminal can manage the call reference number of 2B + D and the existing DSSC-a (CR1) DSSC-a (CR2), which is a completely separate process from C, is newly generated and controls C (CR2).

When a call is requested during a call between the new subscriber A (CR2) and C (DCC-c), the control of the A (CR2) -C subscriber is handed over to the supplementary service control block DSSC-a (CR2) The a (CR2) block is extinguished. A (CR2) subscribers are finally taken control of the DMULC block that directly controls the conference call, the DSSC-a (CR2) block is destroyed, and two processors (CR1 and CR2) And each of the A and C subscribers controls them by one process.

6 shows a process procedure after CR1 (call reference number 1) is in a pending state and CR2 (call origination number 2) is a call from a calling party A (CR2) to be.

A (CR2) is a processing block for controlling the A subscriber with a call reference number CR2 of the A subscriber and DSSC-a (CR2) is a processing block for receiving the control of the A subscriber from the DCC- , DMULC is a conference call service processing block inherited from control of A subscriber from DSSC-a (CR2), DCC-c is a basic call processing block for controlling subscriber, DSSC-c is control of C subscriber from DCC- And the additional service processing block is shown in Fig.

When the subscriber A (CR2) digitizes the function request code (InformIC) for the conference call, the DCC-a (CR2) block receives the information request message (InFormCS) to the DSSC-a (CR2) block is extinguished. The DSSC-a (CR2) transmits a special service code (SsOpCodeRP) to the NTR block when a number translation request (PfxTransRQ) is issued to the NTR block and the NTR block receives the special service code notification (SsOpCodeRP) ). If the call is a digital conference call service, a conference call service request (DigCCSvcRQ) is issued to the DMULC block, and the DSSC-a (CR2) block is extinguished.

The DMULC block, which is a conference call processing block, performs a service transition notification (PairSvcRP) to a held DSSC-a (CR1) block and a DSSC0-b (CR1) block receives a signal and notifies a DMULC block of a call reference number (PairSvcRPAck) The block analyzes this and stores the required call reference (CR) number. The DSSC-a (CR1) notifies subscriber service transition notification (SubsSvcRP) to the called subscriber DSSC-b. The DMULC block performs a subscriber service transition request (SubsSvcRQ) with a DCC-c and a DCC-c performs a subscriber service transition request (DigSubsSvcCtrlRQ) with an additional service processing block DSSC-c. The DSSC- ) And DCC-c disappears.

The DSSC-a (CR1) of the AB (CR1) subscriber is controlled by the DSSC-b, and the DMULC block is then controlled to control the connection / disconnection of the ABC call service. . The DMULC block issues a request to release the existing call switch (AltSwChRelRQ) and a CMX (Conference Mixer) connection request (CmxConnRQ) to GSC (Global Service Control) block in order to convert the call in progress between AB (CR2) .

GSC block is a DMULC block, CMX connection notification (CmxConnRP) indicating that CMX is connected, DMULC block clears all information linking general call between ABs and then connects CMX with the receiving space switch. DMULC block connects with DSSC-b (CR1) block to the DSSC-a block by releasing the switch information change request (SwInfoChngRQ), the DSSC-a releases the existing switch information and connects the space switch CMX to the calling side do. DMULC and DSSC-a are connected through CMX and the hold sound is continuously transmitted. In order to connect CMX between A (CR2) and C, DMULC block requests CMX (Conference Mixer) connection request (CmxConnRQ) as GSC block.

When the GSC block receives the CMX connection notification (CmxConnRP) as a DMULC block, the DMULC block performs CMX channel notification (CmxChRP) to the DSSC-c block, and the DSSC-c block changes the existing switch information to the CMX channel.

In the DMULC block, when a voice switch (time switch, space switch) is connected and the hold tone release request (HoldToneRelRQ) is issued again to the DSSC-a (CR1) block, the DSSC- (HoldToneRelRQ) is released to release the hold tone of the A subscriber, and a voice switch (time switch, space switch) is connected to form a complete three-way call between the ABCs. FIG. 7 is a flowchart of the hold status processing of the called subscribers B and C for a conference call during a trilateral call.

When the conference call service subscriber presses the Hold Key to put the called subscriber in a pending state, the subscriber receives a HoldIC message from the DCC of all called subscribers and transmits a Hold Subscriber Service Control (DSSC) block (HoldRQCS) message to itself and the DCC Process is extinguished.

The newly-originated incoming DSSC blocks send a service transition request (SubsSvcRQ) message to the originating DSSC block and the originating DSSC block sends an additional service transition request (DigSubsSvcCtrlRQ) message to the originating DMULC. The originating DSSC destroys the originating DSSC block and hands control to the originating DMULC block in the same manner as in an incoming call.

The newly created DMULC at the originating side transmits a service transition acknowledgment message (SubssvcRP) to the incoming DSSC blocks, the incoming DSSC blocks receive the message and send a Hold Confirm message (HoldAckCI) to the called subscriber, (HoldToneConnRQ) message and subscriber service notification (SubsSvcRP).

When the Hold DMULC receives a hold tone connect request (HoldToneConnRQ), it cancels the existing time switch and connects Hold Tone to the calling subscriber so that the DMULC, which is an additional service control block between digital subscribers, State).

The procedure until the subscriber DMULC calls a new incoming call and tries to make a conference call in the pending state of the existing DMULC block and the incoming DSSC subscribers is the same as that of the fifth embodiment and will be omitted.

The incoming DSSC blocks are in a pending state and another called party uses a conference call capability request code to attempt a conference call during a call by the calling party.

The originating subscriber digitizes the function request code (InformIC) for the conference call, the originating DCC block receives the information request message (InformCS) to the DSSC and the control is succeeded and the calling DCC block is extinguished. The originating DSSC block analyzes the special service code (SsOpCodeRP) when the NTR block performs the number translation request (PfxTransRQ) and the NTR block performs the special service code notification (SsOpCodeRP) with the DSSC-a (CR3) If it is a call service, it makes a conference call service request (DigCCSvcRQ) to the DMULC block and the DSSC block is extinguished.

When the DSSC blocks request the service transition notification (PairSvcRP) to the called DSSC blocks, the DSSC blocks receive the signal and notify the DMULC block of the call reference number (PairSvcRPAck) to the DMULC block, Analyze this and keep the necessary call reference number. The DMULC block sends a subscriber service transition request (SubsSvcRQ) to the called incoming DCC and the DCC issues a subscriber service transition request (DigSubsSvcCtrlRQ) to the DSSC serving as an additional service processing block. The DSSC notifies the DMULC block of the confirmation message (SubsSvcAck) Is extinguished.

The DMULC block requests the switch (AltSwChRelRQ) and the CMX (Conference Mixer) connection request (CmxConnRQ) in the GSC (Global Service Control) block in order to convert the call in progress into a conference call. The GSC block is a DMULC block. When a CMX connection notification (CmxConnRP) indicating that a CMX is connected is performed, the DMULC block releases all information related to a general call in a call, connects a CMD with a receiving space switch, and a DMULC block transmits a DSSC block (SwInfoChngRQ), the DSSC block relays back to the incoming DSSC block, and the DSSC releases the existing switch information and then connects the space switch to the CMX.

In the DMULC block, when a voice switch (time switch, space switch) is connected and a hold tone release request (HoldToneRelRQ) is issued to the held incoming DSSC blocks B and C, the incoming DSSCs release the hold tone and the voice switch Space switch), and a conference call path between subscribers is formed.

The control process between subscribers expressed in the above description DCC and DSSC have the same role in ASCII and SSCO in the PSTN network. If only the conference call subscriber satisfies the ISDN access protocol, the ISDN can be interworked between subscribers, , It is possible to interwork with the PSTN network.

FIG. 8 is a processing flowchart of a method for releasing a final calling subscriber using a function request code [* 14 *] during a conference call.

If the DMULC of the conference call subscriber presses the function request code [* 14 *] during the conference call, the DMULC block issues a number translation request (PfxTransRQ) to the NTR block. If the NTR block issues a special service code notification (SsOpCodeRP) to the DMULC block, If a service code other than the conference call release code (CC_rel) is received, the DMULC block remains in the conference call state after deleting the request code, and transmits the conference call release request (CC_rel) to the NTR block The CMX release request (CmxRelRQ) is sent to the GSC block to release the CMX of the end subscriber and all of the final called subscriber, and the five subscribers continue the call.

If the called subscriber hangs up during the conference call, all the switch information and CMX of the called subscriber are released, and the other subscriber is kept in a busy state. If the called subscriber is a subscriber, all the switch information connected to the CMX After releasing, switch channel connection request (SwChConnRQ) is made to the SNC to connect the switch to the normal call.

When the SNC sends a switch channel connection notification (SwChConnRP) to the incoming DSSC block, the incoming DSSC block makes a voice switch (time switch, space switch) connection and issues a basic call change request (NormChngRQ) to the calling subscriber DSSC.

The calling DSSC block makes a control request (NormDCCCtrlRQ) with the originating DCC which connects the voice switch (time switch, space switch) and controls the basic call processing block, and the DSSC block is extinguished. The DCC makes a basic call change confirmation request (NormChngACK) to the called subscriber DSSC. When the DSSC performs a basic call control request (NormDCCCtrlRQ) with the incoming call DCC, the DSSC transfers control to the DCC block serving as a basic call processing block in a state where a bilateral call is established, and the DSSC block is extinguished.

FIG. 9 is a state transition diagram based on the implementation of the software of the DMULC, which is a conference call service processing block according to the present invention, and is a skeleton of the concept of the flowchart to lead to an actual source program. When the conference call service request 901 is received as an outmost process for controlling the conference call service, the parent process creates a child process dedicated to the conference call service request.

And a conference call control processor for performing a conference call service control after transferring the control from the DSSC controlling the supplementary service when the service request signal is received while infinitely monitoring whether a request for the conference call service (DigCCSvcRQ) is requested during the communication between the subscriber and the subscriber (902). The hold exchanges information (call reference number) with the subscriber of the DSSC on the other subscriber side (903) to control the actual call connection request (904) to realize the conference call. The subscriber station requests 907 the conference call equipment after releasing 905 the existing call, and forms a conference call after releasing the hold tone of the held subscriber 907. When the called party of the called party or the relayed call requests release of the called party during the conference call, the CMX and the corresponding call are released, and when the conference call function holder releases the call, the CMX of the called party and the call channel are controlled and released ).

In case of a conference call service, a conference call is possible up to a maximum of 6 persons. If a new subscriber requests a service request (909) during a conference call, after releasing the final called party, the existing callers are put on hold each time a service is requested, Add equipment to join the new subscriber to the call.

The conference call function for the digital subscriber of the entire electronic exchanger according to the present invention is applicable not only to the public sector but also to the private exchange system for ISDN. The present invention can be applied to all electronic exchanges using the ISDN subscriber-network signaling method of the International Standard Specification (CCITT), and the ISDN terminal device can receive services without adding existing functions.

Therefore, the present invention can be applied to a private branch exchange satisfying an ISDN subscriber-network interface and is designed with sufficient consideration of interworking with a conventional voice switching network (PSTN), so that a digital subscriber conference calling function can be realized without modification of the existing network And is designed based on the recommendations of the International Standard (CCITT), it can be easily applied to an electronic exchange satisfying the ISDN subscriber-network signaling scheme. Since the present invention implements the functions as one independent block, the independence between the other functions and the blocks to be performed is maintained, thereby improving the efficiency of the call processing function and improving the modularity of the software system. When the conference call function is performed in the existing PSTN network, the subscriber of the conference call function can not know whether the call is correctly connected or released when the conference call is completed. However, in the ISDN network, It is possible to visually confirm the service by providing the message and when the conference call service fails, the subscriber can act actively using the LCD of the terminal, thereby improving the quality of the conference call service.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventive concept as defined by the appended claims and their equivalents. It is not limited.

Claims (1)

A method for processing a digital conference call service applied to an electronic exchange including an access switching subsystem (ASS), an interconnection network subsystem (INS), and a central control subsystem (CCS) The digital conference call processing block receives a request for a digital conference call service from an outmost process, and checks whether the digital conference call service is registered by searching contents of the database. The first step: The digital conference call processing block receiving the digital conference call service request by the Outmost Process generates a child process dedicated to the control of the conference call service and stops its process when the subscriber requests the release thereof, : The child process is responsible for communicating with the process controlling the subscriber. Calculates species data and calculates various data for communicating with the processor controlling subscriber A (optionally subscriber A, B, C, D, E, F settings) and connecting a hold tone to subscribers B, C, D, Step 3: Request the control process to the subscriber A to connect the subscriber A and the subscriber B, C, D, E, and F to the call, and stop and return the subscriber's process when the subscriber requests the subscriber. If the service transition response is not received by the control process of the pending subscriber and there is no response to the service transition, the subscriber in the call takes over control to the basic call processing block in the busy state and returns. Step 4: When a service transition request is received by a control process, a service transition response is received from a subscriber F in a call, and a service control transition response is received from the subscriber F in the call, Step 5: The CMX of the final called subscriber is released using the special service code during the conference call. Then, the child process remains in the busy state. Step 6: If the called party releases the call, all called parties release the call and the conference equipment is released, and their own process is destroyed and returned. Step 7: If the called party requests the call release, If the called subscriber is a subscriber, the CMX is released. Then, the B channel is reallocated again for resuming the call, the resume request is made to the subscriber B, When receiving a transition request to the processing block and receiving a control transition confirmation notification, the control unit passes control to the base call processing block after the connection of the quantum call and returns Wherein the digital conference call processing method comprises the steps of: