KR0126851B1 - Method for processing the inquiry of call status in exchange system - Google Patents

Abstract

A call state consultation processing method in a full electronic exchange quickly senses a call state disagreement phenomenon occurred by abnormal situation through a subscriber call state consultation step, prevent a network waste, and minimizes a call accounting disagreement public discontent of a subscriber. The method performs a periodic digital subscriber call state consult function in a busy state of a full electronic exchange, and minimizes a cost for modifying a program and a development cost.

Description

How to Handle Call Status Inquiries in Electronic Switching System

1 is a schematic control structure diagram of an all-electronic exchanger which is a distributed control system to which the present invention is applied.

2A through 2D are flowcharts of a call state query processing procedure in an electronic switch according to the present invention.

* Explanation of symbols for the main parts of the drawings

10a to 10c: Access Switching Subsystem (ASS)

11a to 11c: Access Switching Processor (ASP)

12a to 12c: LDL (Local Data Link)

13c: Signaling Message Handling Processor (SMHP)

20: INS (Interconnection Network Subsystem)

21: INP (Interconnection Network Processor)

22: Number Translation Processor (NTP)

30: Central Control Subsystem (CCS)

The present invention relates to a call state query processing method in an electronic switchboard, and in particular, the call state mismatch phenomenon that may occur due to an abnormal situation through a subscriber call state inquiry process as soon as possible, the waste of resources of the network and the call charge mismatch complaint of the subscriber The present invention relates to a call state query processing method in an all-electronic exchange.

At present, various kinds of networks exist around us such as telephone network, teletex network, data communication network and packet network. However, each network is developed independently and supports only one type of service, and lacks compatibility between networks. In addition, each network is realized with individual protocols, speeds, standards, and circuit standards. Due to legal problems and limitations of analog technology, there are many difficulties in interworking between networks.

Therefore, it is possible to solve the above problems, and it is required to build a communication base that is more economical, has superior quality, and has a broader communication category. To this end, the concept of an Integrated Service Digital Network (ISDN) has emerged, which allows a limited number of users to receive a wide range of services using a standardized multipurpose matching device. Global protocols have been defined.

In order to establish ISDN in Korea and provide various services to ISDN users, introduction of DSSI (Digital Subscriber Signaling System No. 1) and application of new technology development is inevitable.

In other words, in an electronic switch used as a node of an integrated information communication network, an error of a subscriber station, a malfunction of a digital subscriber board, a restart or abnormality of a network layer 2 processor, an ISAP (ISDN Subscriber Access Processor) and an ASP (access) IPC signal loss may occur due to a temporary failure of inter-processor communication (IPC) between switching processors.

When such an abnormal situation occurs, when call progress or call release is in progress, the call state of the network and the terminal device eventually transitions to a null state by a timer operated at Layer 3 of the network or the terminal device. This can lead to a call state agreement.

However, if the network does not receive the release related message (DISCONNECT, RESEASE, R ELEASE COMPLETE, etc.) or the release related IPC signal due to an abnormal situation on the busy call, the network remains indefinitely busy. This results in inconsistent call time and waste of system resources such as switches, memory, and CPU.

The present invention has been made to solve the above problems, it is to detect the call state inconsistency that can occur in an abnormal situation in the electronic switch as soon as possible to minimize the resource waste of the network and the subscriber's call billing mismatch complaints It is an object of the present invention to provide a method for handling call state inquiries in an electronic exchange.

In order to achieve the above object, the present invention provides a call state query processing method applied to an electronic switch having an access switching subsystem (ASS), an inter-connection network subsystem (INS), and a central control subsystem (CCS). When the call control process of DCC (Digital Subscriber Circuit Call Control) receives the incoming call response from the call control process while the call control process is in progress, the call status monitoring timer is driven for the call status inquiry of the subscriber station. The first step to do; A second step of, when the originating control process of the DCC receives the call state monitoring timer termination from the busy state, transmitting a “STATUS ENQUIRY” message to the subscriber station and driving the call state monitoring timer; When the DCC originating control process receives a "STATUS" message from the subscriber station in the busy state, it analyzes the call state information in the "STATUS" message and performs the call release procedure when it is not in the busy state. Performing a third step; When the DCC originating control process receives a “data link cutout notification” signal from the DSI block while in a call, it performs interruption of an active timer, cuts into a call, sends a “outgoing call notification” signal, reports final charge, and releases a channel. A fourth step of terminating the process thereafter; Receiving a “CONNECT” signal from the subscriber station when the incoming call control process of the DCC is in progress of establishing the incoming call, driving a call state monitoring timer to call a call state of the subscriber station periodically; A sixth step of, when the incoming call control process of the DCC receives the termination of the call state monitoring timer in a busy state, transmitting a "STATUS ENQUIRY" message to the subscriber station and driving the call state monitoring timer; When the DCC incoming call control process receives a "STATUS" message from the subscriber station in the busy state, it analyzes the call state information in the "STATUS" message and performs the call release procedure when the call is not busy. Performing a seventh step; And when the incoming call control process of DCC receives the "data link cutting notification" signal from the DSI block in a busy state, checks whether the received "data link cutting notification" signal is related to the terminal device providing the call service. And the eighth step of terminating the process after performing a "release call notification" signal transmission to the call control process and channel release.

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

FIG. 1 is a schematic control structure of an all-electronic exchanger which is a distributed control system to which the present invention is applied. The all-electronic switching system includes an access switching subsystem (ASS) 10A to 10C and an interconnection network subsystem 20 (INS). In addition, three bush steams of the central control subsystem (CCS) 30 are configured.

ASS is classified into ASS_S (Subscriber) (10A), ASS_T (Trunk) (10B), and ASS_7 (No. 7 Signaling System) (10C), depending on the function, ASS_S (Access Switching Processor) (ASP) of ASS_S (10A) Performs the call processing function for the subscriber accommodated in the exchange, the ASP 11B of the ASS_T (10B) performs the inter-office relay line call processing function, and the ASP (11C) of the ASS_7 (10C) and the signaling message handling processor (SMHP). (13C) is No. 7 Functions as a signaling message transfer part (MTP) and a signaling connection control part (SCCP).

The NTP (Number Translation Processor) 22 and the INP (Interconnection Network Processor) 21 of the INS 20 perform a number translation function, a root control function, and a spatial partition switch control function, which are call processing functions commonly required in each ASS. In addition, the CCS 30 performs the operation and preservation function of the system.

Each subsystem is connected to the INS 20 via LDL (Local Data Link) 12A-12C to form an interprocessor inter-system communication network.

The subscriber call state inquiry function of the electronic switch is implemented in a software block (DCC: Digital subscriber circuit call control) mounted in the ASP 11A belonging to the line and trunk access subsystem (LTAS) of the ASS_S (10A). It consists of three processes: the main process controlling the process and the peripheral processor, the originating process controlling the digital subscriber outgoing call processing, and the incoming process controlling the digital subscriber incoming call processing. In conjunction with 14A), it performs a subscriber call status inquiry function.

The DCC operates a periodic timer for a call that is in a busy state. Whenever the timer expires, the DCC sends a call status request signal to the DSI so that a layer 3 message of “STATUS ENQUIRY” is displayed. To be sent to.

The DSI receives a "STATUS" message including the call status of the terminal from Layer 3 of the terminal device through the network layer 2 processor, and transmits the call status signal to the DCC through the IPC.

When the DCC receives the call status signal from the DSI, the call state mismatch between the network and the terminal equipment is searched through a comparison procedure between the call status of the terminal equipment included in the call status signal and the call status of the network. For calls that have inconsistencies, a call release procedure that follows the call state mismatch is initiated.

2 is a flowchart illustrating a call state query processing procedure flow of an electronic switch according to the present invention.

The subscriber station shall respond to the "STATUS ENQUIRY" message received from the network with a "STATUS" message containing information indicating the call status of the current subscriber station.

As shown in FIG. 2A, when the originating control process of the DCC is in the process of making an outgoing call (101) and receives a signal of the "incoming answer notification" from the incoming control process (102), a timer that is operating to monitor the call establishment progress is started. Stop (103), connect the call path (104). Thereafter, the call state monitoring timer is driven for the periodical call state inquiry of the subscriber station (105). After transmitting the message “CONNECT” to the subscriber station (106), the mobile station transitions to the busy state (107). ).

On the other hand, when the DCC originating control process receives the call state monitoring timer termination in the busy state (201) (220), and transmits a "STATUS ENQUIRY" message to the subscriber station (221), The call state monitoring timer is driven to call the call state (222), and waits for reception of a "STATUS" message from the subscriber station (223).

On the other hand, when receiving a "STATUS" message from the subscriber station device as shown in Figure 2B (209), the call state information in the message is analyzed to check the call state of the terminal device (210). If the call state of the terminal device is busy (211), the call state is maintained (212), and if the call state of the terminal device is idle (211), the running timer is stopped (203), and the call path is closed. After cutting (204), and transmitting the "call release notification" signal to the call control process (205), and after performing the final billing notification procedure and channel release procedure (206,207), the call control process is terminated (208).

If the call state of the terminal device is not busy or idle (211), the timer that is in operation is stopped (213), the set call path is disconnected (214), and the "call release notification" signal is transmitted to the incoming call control process. (215) and the final billing notification procedure (216). In addition, the subscriber station sends a "RELEASE" message including a cause information element indicating a call release due to a call state mismatch to the subscriber station and requests the subscriber station to proceed with the call release (217). A TSE, which is a 4 second timer, is driven (218) for the reception of the message " RELEASE COMPLETE ".

When the originating control process receives the "data link disconnection notification" signal from the DSI block in the busy state (202), the same process as in the case where the call state of the terminal device is in the idle state is performed (203 to 208).

Then, as shown in FIG. 2C, when the incoming call control process of the DCC is in the process of setting up the incoming call (301) and receives a "CONNECT" message from the subscriber station (302), a timer that is operating to monitor the call establishment progress. Stop (303), cut off the ringback tone (304) if it is providing ringback tones (304), send a "call-to-answer notification" signal to the calling control process (305), connect the call (306), and then cycle The call state monitoring timer is driven for the call state inquiry of the subscriber station (307), and after the message CONNECT ACKNOWLEDGE is transmitted to the subscriber station (308), the call state transitions to the busy state (309). .

Further, as shown in FIG. 2D, when the incoming call control process of the DCC receives a call state monitoring timer termination in a busy state (401) (419), it transmits a "STATUS ENQUIRY" message to the subscriber station (420). After the call state monitoring timer is driven (421) for a call state inquiry in the next period, it waits for reception of a "STATUS" message from the subscriber station (422).

When receiving a "STATUS" message from the subscriber station (409), and analyzes the call state information in the message to check the call state of the terminal (410), if the call state of the terminal device is busy (411) If the call state of the terminal is in the idle state (412) (411), the running timer is stopped (404), the call path is cut (405), and the call control process is called "Delivery Release Notification". Transmit a signal (406) and terminate the incoming call control process (407, 408).

If the call state of the terminal is not busy or idle (411), the timer in operation is stopped (413), the set call path is disconnected (414), and the "call notification" signal is transmitted to the call control process ( 415), the subscriber station sends a "RELEASE" message including a cause information element indicating the call release due to a call state mismatch to the subscriber station requesting that the subscriber station proceed with the call release (416), A TSE, which is a 4 second timer, is driven to receive a "REELEASE COMPLETE" message (417), and the state transitions to the release request state (418).

If the incoming call control process receives a “data link disconnection notification” signal from the DSI block in a busy state (402), the terminal having disconnected the data link confirms that the incoming call control process is a terminal device providing call service. In step 403, the same process as in the case where the call state of the terminal device is in the idle state is performed (404 to 408).

As described above, the present invention provides a subscriber station apparatus, a digital subscriber line, a terminal layer 2, and a digital subscriber of a network by performing a periodic digital subscriber call state inquiry function while an electronic switch used as a node of a general information communication network is busy. Incoming calls that can occur due to abnormal conditions such as devices and processors in charge of interface functions, call state of subscriber station is not busy, but call state of network is kept on call, increasing subscriber complaints about billing, network and terminal This can be avoided by the mismatch of call state and the long-term occupation of call resources such as related channels.

In addition, the implementation of the digital subscriber call status query procedure can provide the implementation method to minimize the modification of the existing call processing program, it is possible to obtain the effect of the program change and the development cost minimized by the addition of the function.

Claims (3)

In a call state query processing method applied to an electronic switch having an ASS (Access Switching Subsystem) (10A to 10C), an Inter-connection Network Subsystem (INS) 20 and a Central Control Subsystem (CCS) 30, When the call control process of DCC (Digital Subscriber Circuit Call Control) receives outgoing call notification from the call control process while the call setup is in progress, the call state monitoring timer is driven to call the call status of the subscriber station periodically. First steps 101 to 107; If the DCC originating control process receives the call state monitoring timer termination while in a busy state, a second step (220 to 223) of transmitting a "STATUS ENQUIRY" message to the subscriber station and driving the call state monitoring timer; ; When the DCC originating control process receives a "STATUS" message from the subscriber station in the busy state, it analyzes the call state information in the "STATUS" message and performs the call release procedure if it is not busy. Performing a third step (203 to 219); When the DCC originating control process receives a “data link cut notification” signal from the DSI block while in a call, it performs interruption of the active timer, cuts into a call, sends a “call release notification” signal, sends final charge notification, and releases the channel. A fourth step (202 to 208) after which the process is terminated; A fifth step of driving a call state monitoring timer for a call state inquiry of a periodic subscriber station by receiving a "CONNECT" signal from the subscriber station while the incoming call control process of the DCC is in progress of establishing a call; 301 to 309; When the incoming call control process of the DCC receives a call state monitoring timer termination while in a busy state, a sixth step (419 to 422) of transmitting a “STATUS ENQUIRY” message to the subscriber station and driving the call state monitoring timer; ; When the DCC incoming call control process receives a "STATUS" message from the subscriber station in the busy state, it analyzes the call state information of the "STATUS" message and performs the call release procedure when the call is not busy. Performing a seventh step (404 to 418); And when the incoming call control process of DCC receives the "data link cutting notification" signal from the DSI block in a busy state, checks whether the received "data link cutting notification" signal is related to the terminal device providing the call service. Call status query in an electronic switchgear comprising an eighth step (402 to 408) for terminating the process after performing a disconnection, transmitting a "notification of release" signal to a call control process, and channel release. Treatment method. The ninth step of claim 1, wherein the third step (203 to 219), when receiving a "STATUS" message from the subscriber station, analyzes the call state information in the message to check the call state of the terminal device. Steps 209 to 211; A tenth step (212) of maintaining a busy state if the call state of the terminal device is busy in the ninth step; In the ninth step, if the call state of the terminal device is in the idle state, the running timer is interrupted, the call path is disconnected, and the "call release notification" signal is transmitted to the incoming call control process, the final billing notification procedure and the channel release procedure. An eleventh step (203 to 208) for terminating the originating control process after performing the method; In the ninth step, if the call state of the terminal device is not in a call state or in a pause state, the timer that is in operation is stopped, the set call path is disconnected, the call release control signal is transmitted to the incoming call control process, and the final charge notification is received. Performing a procedure, transmitting a “RELEASE” message to the subscriber station, running a 4 second timer to receive a “RELEASE COMPLETE” message from the terminal, and transitioning to the release request state; Call status query processing method in an electronic switch, comprising steps (213 to 219). The method of claim 1, wherein the seventh step (404 to 418), when receiving a "STATUS" message from the subscriber station, the call state information in the message to analyze the call state of the terminal device; Steps 409 to 411; A tenth step (412) of maintaining a busy state if the call state of the terminal device is busy in the ninth step; In the ninth step, when the call state of the terminal device is in the dormant state, the operating timer is stopped, the call path is disconnected, the call canceling notification signal is transmitted to the call control process, and the call control process is terminated. Steps 404-408; In the ninth step, if the call state of the terminal device is not in a busy state or a pause state, the timer that is in operation is stopped, the set call path is disconnected, the call termination process is transmitted to the call control process, and the subscriber station device is connected. And a twelfth step (413 to 418) for transmitting a "RELEASE" message to the mobile station, driving a 4 second timer for receiving a "RELEASE COMPLETE" message from the terminal device, and transitioning to a release request state. Call state query processing method in an electronic switch, characterized in that.