KR20060035081A - Method of internet protocol terminals for providing a plurality of call services and ip terminals enabling the method - Google Patents

Abstract

The present invention relates to a method of operating an IP terminal for receiving a call service and to such an IP terminal, and more particularly, to provide a predetermined call service by controlling an IP terminal through various types of messages in an IP exchange system. A method of operating an IP terminal and an IP terminal for performing such an operation.

According to the present invention, the function of the IP terminal can be minimized, and the call service can be provided in the IP exchange system, and if the additional call service is developed, the service is provided only by upgrading the IP exchange system without changing the IP terminal. An IP terminal capable of receiving is provided.

IP Switching System, Call Service, Call Transfer, Call Hold, Conference Call

Description

Method of operation of an IP terminal for receiving a call service and its IP terminal TECHNICAL FIELD

1 is a diagram illustrating a configuration of a call service providing system through a general IP network.

2 is a diagram illustrating an example of an IP exchange system that can be employed to provide a call service to an IP terminal according to the present invention.

3A is a diagram illustrating a system configuration for receiving a call service in an IP terminal according to the present invention.

3B is a diagram illustrating a configuration module of an IP terminal according to the present invention.

4 is a state machine illustrating a state transition of an IP terminal provided with various call services according to an embodiment of the present invention.

FIG. 5A is a state machine illustrating a state transition of an IP terminal receiving a call hold service according to an embodiment of the present invention.

FIG. 5B is a state machine illustrating a state transition of an IP terminal receiving a call waiting service according to an embodiment of the present invention.

5C is a state machine illustrating a state transition of an IP terminal receiving a call transfer service according to an embodiment of the present invention.

FIG. 5D is a state machine illustrating a state transition of an IP terminal receiving a conference call or a three way call service according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

200: IP switch system

201: subscriber information database 202: call service control unit

203: database management unit 204: call processing unit

205: interface unit 206: OAM

The present invention relates to a method of operating an IP terminal for receiving a call service and to such an IP terminal, and more particularly, to provide a predetermined call service by controlling an IP terminal through various types of messages in an IP exchange system. A method of operating an IP terminal and an IP terminal for performing such an operation.

Today, due to the rapid dissemination of the Internet and the demand for various services, the IP (Internet Protocol) network is dramatically developed in terms of performance and service, and the demand for more various services is continuously emerging. An example of such a requirement is the delivery of voice signals over an IP network. The transmission of voice signals through the IP network is supported by Voice over Internet Protocol (VoIP), which is now becoming a big part of the IP network along with the transmission of data, thereby increasing the demand for various voice signal transmission functions. .

The basic function of the Session Initiation Protocol, which has recently attracted the attention of the multimedia service, is to call voice over Internet Protocol (VoIP) terminals capable of voice communication such as computers, IP phones, PDAs, and mobile phones. To set. This call setup function is not much different from the ITU-T H.323 protocol call setup function. SIP is designed after the text-based Simple Mail Transfer Protocol (STMP) and Hyper Text Transfer Protocol (HTTP), and is a client / server architecture in which the server responds to the call when the client initiates the call. It is based on that. SIP has the advantage of being easy to troubleshoot and network debug by following these existing text-based Internet standards. In addition, SIP is easier to implement than ITU-T's H.323 protocol and has the advantage of being compatible with other services because it is an Internet standard. In particular, SIP is designed to be included as a component of all Internet terminals, all application services, and all network equipment to perform functions such as call setup, call management, and application service requests.

Although SIP was developed as a call setup protocol for VoIP, it is expected to perform core functions in next-generation communication network because it is easy to implement and compatible with other services, and the conventional circuit network gradually becomes an IP network. As the network is replaced by a packet network, a circuit switch is being replaced by a switch suitable for IP.

In the conventional IP switching system, in addition to the call signaling channel, a data channel for managing information of the subscriber station or providing data requested from the subscriber station is separately required. In other words, MGCP (Media Gateway Control Protocol) used in the conventional IP switching system is a standard protocol for signal operation and session management required during a conference, and the data format required for a circuit switched network is converted into a data format required for a packet switched network. Defines the communication method between the media gateway and the media gateway controller. MGCP can only be used to establish, manage, or terminate calls between multiple endpoints, but is not a protocol for managing two logical sessions for one IP terminal.

In addition, when two channels are separated for one IP terminal, there is a problem of being more affected by the environment of the Internet network such as a NAT environment or a firewall, and there is a problem that it is not easy to manage two channels. do.

In addition, since various call service methods defined in the SIP are all defined around the IP terminal, in order to perform the functions defined in the SIP in the corresponding IP terminal, the IP terminal itself must include an expensive configuration module for supporting the corresponding function. There is a problem. Therefore, in order to provide call services such as call hold, call transfer, three-way call, conference call, call waiting, etc. defined in SIP, the corresponding IP service had to be provided with the corresponding call service. In such a conventional IP terminal, it is not easy to add a function or a service for receiving a specific call service, and there is a problem in that the corresponding call service cannot be used when the corresponding IP service does not provide a corresponding call service function.

As a result, the price of the multi-function IP terminal has been increased, and it has been an obstacle to securing flexibility in providing call service.

An object of the present invention is to be able to receive a variety of call services in a low-cost IP terminal with only minimal functionality.

In addition, an object of the present invention is to provide an IP terminal capable of minimizing the function of an IP terminal and receiving and using a call service in an IP exchange system.

In addition, an object of the present invention is to provide an IP terminal that can be provided with the service only by upgrading the IP exchange system without changing the IP terminal when additional call services are developed.

In addition, the present invention is to minimize the function of the IP terminal while minimizing the function of the IP switch system, it is not necessary to have a mixer (device) for the call service or an additional device for reproducing the pending sound in the IP terminal It is an object to provide a terminal.                         

In addition, an object of the present invention is to reduce the manufacturing cost of the IP terminal by minimizing the function of the IP terminal and thereby to activate the call service using the IP network.

In order to achieve the above object and to solve the above-mentioned problems of the prior art, the operation method of the IP terminal for receiving a call service from the IP exchange system according to the present invention, the state information for the first and second calls; Maintaining a state management unit for storing the state information, wherein the state information for the first call and the second call is IDLE; Changing state information of the first call to DIAL in response to a user inputting a Hook OFF; Transmitting a call connection request message to a first party through the first call to the IP exchange system, and status information of the first call stored in the state manager in response to receiving a call connection response message for the call connection request message. Changing to BUSY; Receiving a call hold event from the user and transmitting a call hold event message corresponding to the call hold event to the IP exchange system; Receiving a call hold acceptance message for the call hold event from the IP exchange system, changing state information of the first call stored in the state manager to HOLD, and changing state information of the second call to DIAL; Receiving connection information about a second party from the user, and transmitting a call connection request message to the IP exchange system to change the state information of the second call to SEIZE; And receiving a call connection response message from the IP exchange system and changing the state information of the second call to BUSY.

In addition, according to still another embodiment of the present invention, an operation method of an IP terminal for receiving a call service from an IP exchange system includes: maintaining a state management unit storing state information on first and second calls; Status information for the first and second calls is IDLE; Changing state information of the first call to DIAL in response to a user inputting a Hook OFF; Transmitting a call connection request message to a first party through the first call to the IP exchange system, and status information of the first call stored in the state manager in response to receiving a call connection response message for the call connection request message. Changing to BUSY; Receiving a call connection request message from a second party from the IP exchange system and changing state information of the second call to RING; Receiving a call hold event from the user and transmitting a call hold event message for the call hold event to the IP exchange system; And receiving the call hold acceptance message for the call hold event from the IP exchange system, changing the state information of the first call stored in the state manager to HOLD, and responding to the call connection request message, the state information of the second call. It characterized in that it comprises a step of changing to BUSY.

Hereinafter, the terms used in the present specification will be summarized and the present invention will be described in detail with reference to the accompanying drawings.

* Glossary of Terms *

1) IP terminal

As used herein, the term "IP terminal" is a concept that includes all communication terminals capable of supporting both voice calls or video and voice calls through the Internet Protocol, and in particular, legacy communication. A concept encompassing all terminal devices that can be implemented in the form of a gateway device required to use an IP call service according to the present invention using a terminal.

2) call service

As used herein, the term "call service" refers to a voice call between a caller and a receiver, or a basic service that enables voice and video calls, as well as a voice call such as a call hold service or a call waiting service described below. It is used as a concept that includes all services provided.

3) Call Hold Service

Call hold service means a service that allows a service subscriber to put a call on hold and try a new call. The call holding service may be initiated by a service subscriber who is currently in a call or may be implemented as a service that holds a call in progress according to a call connection request message transmitted from a third subscriber during a current call.

4) Call Transfer Service

Call transfer service means a service for handing a call received to subscriber A to subscriber C. For example, if a call arrives at the call transfer service subscriber A, and the subscriber A needs to transfer a call during the call, the call is put on hold with the current caller, subscriber B. The subscriber A can connect the call between the subscriber B and the subscriber C by inputting connection information such as the terminal number of the subscriber C, connecting the call with the subscriber C, and then entering a call transfer event.

5) Three Way Call Service

This means that a subscriber who is currently making a normal call holds a call with a subscriber who is in a call, then calls a third party and then calls a subscriber who is on hold again, so that the third party can call simultaneously. For example, if a subscriber A enters a call hold event so that subscribers A and B make a three-way call with subscriber C during the call, the call with subscriber B is put on hold. Subscriber A calls subscriber C by inputting connection information such as subscriber C's terminal number. Subscriber A can also call with subscriber B on hold by entering a call hold release event while on call with subscriber C.

6) Conference Call Service

The next service is a feature that allows four or more people to talk simultaneously. When subscriber A and subscriber B enter a call hold event to make a three-way call with subscriber C during a call, the call with subscriber B is put on hold. Subscriber A calls subscriber C by entering the terminal number of subscriber C. In this case, the subscriber B maintains the call hold state. Subscriber A enters a call hold release event in a call state with subscriber C, and subscriber B, who is in call hold state, can also call together. After that, by repeating the above process, four or more conferences are possible.

7) Call Waiting Service

If subscriber A has registered for call waiting service, when subscriber B is called with subscriber B during the call, subscriber A is signaled that another call is being called. In this case, when the subscriber A inputs a call hold event, the call between the subscriber A and the subscriber B becomes a pending state and means a service to which the call between the subscriber A and the subscriber C is connected. For example, if subscriber C calls subscriber A and subscriber A is on call with subscriber B, subscriber A hears a signal that subscriber C is on call and enters a call hold event. In this case, the call with subscriber B is placed on hold and the call between subscriber A and subscriber C is in a call state.

The IP terminal according to the present invention is preferably designed to satisfy some of the operating conditions described below.

(1) The IP terminal according to the present invention should be able to manage two call sessions. These two call sessions may be distinguished using a call ID assigned to a specific call.

(2) The IP terminal according to the present invention should be able to perform state management for two call sessions. The state management may be performed through a predetermined state machine, and the state machine may be implemented as an application of an IP terminal.

(3) Among the state machines operating in the IP terminal according to the present invention, the states of the first and second calls are BUSY / BUSY or SEIZE / SEIZE are not allowed. That is, in order for the second call to be in a state except IDLE or RING, the first call state information must be HOLD.

2 is a diagram illustrating an example of an IP exchange system 200 capable of providing various call services to an IP terminal according to the present invention.

The IP exchange system 200 may include a subscriber information database 201, a call service control unit 202, a database management unit 203, a call processing unit 204, an interface unit 205, and an OAM 206. .

The subscriber information database 201 includes information on the presence or absence of call service authority for each subscriber.

The call service controller 202 may determine whether to provide a specific call service to a predetermined subscriber by referring to the subscriber information database 201. In addition, it controls the transmission relay of a predetermined message as described above, or the transmission of a response message to the predetermined message.

The database manager 203 manages the subscriber information database 201, such as adding, changing, or deleting information on call service authority for each subscriber in the subscriber information database 201 of the IP exchange system 200.

The interface unit 205 may transmit or receive audio data or video data in real time to the IP terminal of each subscriber in a call, or transmit and receive messages for providing a predetermined call service between the IP terminals of each subscriber.

Operations, Administration and Maintenance (OAM) 206 provides the operator with an interface for the operation, management and maintenance of the IP exchanger system. It means a management function group that outputs operation status or statistical contents.

The IP exchanger system may be a system that supports Session Initiation Protocol (SIP) such as IP Internet Protocol-Private Branch Exchange (PBX), IP-Centrex, soft switch, SIP proxy server or gateway (Gateway). . IP-PBX is an enterprise voice communication system that provides telephony service based on IP. The IP-PBX can be classified into 1) IP-Enable, 2) Converged, and 3) All-IP. IP-Centrex is a group of subscribers' phone lines that can be managed in the same way as an internal PBX but does not require the purchase or maintenance of equipment such as a PBX.

The soft switch, referred to as a "call agent" or a "media gateway controller", refers to a software switch that provides call control and signaling to a Next Generation Network (NGN).

The block diagram of the IP exchange system for providing a call service according to the present invention shown in FIG. 2 is merely classified from a functional point of view, and does not mean an actual implementation method or a hardware method. One or more of the configuration modules illustrated in FIG. 2 may be integrated or subdivided into one or more configuration modules, which will be apparent to those of ordinary skill in the art.

3A is a diagram illustrating an overall system configuration for receiving a call service in an IP terminal according to the present invention.

The user 301, the first counterpart 302, and the second counterpart 303 are entities that receive various call services through a communication network such as an IP network. The IP terminal provided at the user 301, the first counterpart 302, and the second counterpart 303 is provided with various call services from the IP exchange system 310 through a state setting method according to the present invention described later. It is possible.

3B is a diagram illustrating a configuration module of an IP terminal according to the present invention. Referring to FIG. 3B, the IP terminal according to the present invention may include a first call state manager 351, a second call state manager 352, a call processor 360, and a communication interface 370.

The first call state manager 351 and the second call state manager 352 store state information of the first and second calls, which will be described later with reference to FIG. 4 below. According to the implementation, the first call state management unit 351 and the second call state management unit 352 may be integrated into one state management unit, and for the convenience of description, the state information of the first and second calls is described herein. The storage is described as being performed in a separate configuration module.

The call processing unit 360 controls call processing of the IP terminal according to the present invention according to the state information of the first call and the second call stored in the first call state manager 351 and the second call state manager 352. Play a role. In particular, the call processing unit 360 manages the state information of the first call and the second call according to the state machine described later in FIG. 4 below, and the first call when the state information of the first call and the second call is changed. The state information stored in the state manager 351 and the second call state manager 352 is updated.

The communication interface unit 370 transmits the call data according to the first call and the second call to the IP exchange system under the control of the call processor 360 and receives the call related data received from the IP exchange system. In charge of.

Hereinafter, an operation method of an IP terminal according to the present invention will be described in detail with reference to FIG. 4.

4 is a state machine illustrating a state transition of an IP terminal provided with various call services according to an embodiment of the present invention.

4, an IP terminal according to the present invention may have one or more state information. In the IP terminal according to the present invention, in order to receive a call service, a single communication channel may be physically divided into two channels by a software module in the IP terminal, thereby using various functions of the IP exchange system. It is possible to receive call service. In FIG. 4 and the following drawings, "1st" means a session state for the first call maintained and managed by the IP terminal according to the present invention, and "2nd" means that the IP terminal according to the present invention is maintained and managed. Session state for the second call.

A definition of the terminal state of the state machine shown in FIG. 4 is as follows.

(1) IDLE: The handset of the IP terminal is hooked (Hook ON) to make a call.

(2) DIAL: A state where the user is holding a handset of the IP terminal (Hook OFF) and inputting call connection information, before transmitting a call connection request message for attempting a new call.

(3) SEIZE: Status after receiving a call connection response message after sending a call connection request message for attempting a new call.

(4) BUSY: Initiated call by receiving call answering message

(5) RING: A call connection request message has been received for a new call.

(6) HOLD: Holds the call in the IP terminal.

(7) HELD: HOLD is received from the IP terminal of the called party.

4 and 5A to 5D described below, when the first call is in the IDLE state and the second call is not in the IDLE state, the first call is not the IDLE state and the second call is considered to be the same as the IDLE state. In addition, the transmission of the call hold event is performed in principle by using the currently active call. That is, when the first call is in the HOLD state and the second call is in the BUSY state, since the second call is in an activated state, the call hold event message is transmitted using the information of the second call.

Referring back to FIG. 4, in state 401 the first and second calls are IDLE states.

The state 401 means a state in which no call is being made in the IP terminal.

In state 401, if the user hooks off the handset of the IP terminal (or presses the hook off button means of the speaker phone), the state information is updated to state 402.

In state 402, the first call is a DIAL and the second call is an IDLE state. In the state 402, when a hook flash or a redial event is input from the user, all the call connection information collected is cleared, and the state transitions to the state of collecting the connection information again. When the Hook ON event is input from the user in the state 402, all the call connection information collected is cleared, and the state information of the first call is changed to IDLE to transition to the state 401. In addition, when the call connection request message for the first call is transmitted in state 402, the state transitions to the first call SEIZE / second call IDLE of state 403. The call connection request message may be an INVITE message of a session initiation protocol.

Upon receiving a call connection response message from the IP exchange system in state 403, the state transitions to state 408, whereby the state of the IP terminal is called first call BUSY / second call IDLE. The call connection response message may be a 200 OK message when using SIP. When the first call is in the BUSY state and the second call is in the IDLE state 408, a call hold event (such as a user's hook FLASH input or a special function key input provided in an IP terminal such as a FLASH key or a call hold key) is input from the user. The IP terminal sends a call hold event message for the first call to the IP exchanger system, and the IP switch system transmits a call hold accept message for the call hold event message to the IP terminal. The IP terminal receives the call hold accept message and changes the first call to the HOLD state and the second call to the DIAL state (state 404). The call hold accept message may be a Re-INVITE message in case of SIP, and in this case, information for performing call hold may be included as detailed information included in the message.

If a call hold release event for the first call is input from the user in state 404, the IP terminal sends the call hold release event to the IP exchange system, and the call hold for the first call from the IP exchange system. The release message may be received and transitioned back to state 408.

In state 404, the IP terminal sends a call connection request message for the second call, and the first call transitions to state 405 where the HOLD / second call is SEIZE. In this case, if there is an error in the call connection information for the second call or there is no authority of the call service based on the call connection information of the second call, the IP exchange system may call the call for the second call failure message and the call for the first call. The hold release message may be transmitted to the IP terminal, and the status information of the IP terminal receiving the hold release message may be changed to the first call BUSY / second call IDLE (state 408).

When state 405 receives a call connection response message for a second call from the IP exchange system, the state is the first call and the HOLD / second call is the BUSY state (state 406).

In addition, when the call cancellation event for the second call is received from the user in the state 405, the call connection cancellation message is transmitted to the IP exchange system, and the call cancellation response message and the first call response message for the second call are received from the IP exchange system. A call hold release message for the call may be received and transitioned to state 408. The call connection cancellation message may be a CANCEL message in case of SIP. In addition, in the state 405, when there is no response from the second party receiving the second call, the IP terminal receives a call connection failure message for the second call from the IP exchange system, and holds the call for the first call. A release event may be sent to the IP exchange system, which may receive a call hold release message for the first call from the IP exchange system and transition to state 408.

Transitioning back to state 401 when a call termination request message for the first call is sent or received in state 408. The call termination request message may be a BYE message in case of SIP.

In the state 408, when the call connection request message for the second call is received from the IP exchange system (if a new call connection request is received from the second party), the IP terminal receives the first call BUSY / second call RING state ( 407). If a call hold event (such as a user's hook FLASH input or a special function key provided in an IP terminal such as a FLASH key or a call hold key) is input from the user in state 406, the IP terminal holds the call for the first call. The event message is delivered to the IP exchange system, and the IP exchange system sends a call pending accept message for the call pending event message to the IP terminal. The IP terminal sends a call connection response message for the second call to the IP exchange system to change the first call to the HOLD state and the second call to the BUSY state (state 406).

When the call termination request message for the first call is received in the state 407 (when there is a call termination request from the first party who is the other party of the first call), the second call is RING, and the first call is IDLE (409). ), And in state 409 the IP terminal sends a connection response message for the second call and transitions back to state 408. The first call IDLE / second call ring state is considered to be the same as the first call ring / second call IDLE state.

If a call cancellation event or the like is input from the second party, the other party of the second call, in the state 407, the IP terminal receives a call connection cancellation message for the second call from the IP exchange system and transitions to the state 408.

In the state 408, when a call hold perform message for a first call is received (received a call hold perform message from a first party, which is the other party of the first call), the IP terminal sends a call first HELD / call ID IDLE. The state transitions to the state 410. The call hold performance message may be a Re-INVITE message in case of SIP, and in this case, information for call hold performance may be included as detailed information included in the message. In the state 410, if the call hold release message for the first call is received from the IP exchange system, the state transitions back to the state 408, and in state 410, the call is released to the first call in response to an event such as a user's hook ON. Transition to state 401 by sending a call termination request message.

When the call connection request message for the first call is received from the IP exchange system in the state 401, the first call transitions to the state 409 in which the first call is RING and the second call is IDLE. After receiving an event such as Hook OFF from the user and transmitting a call connection response message for the first call, the first call may transition to the state 408 in which the BUSY / second call is IDLE.

In the case of the call hold acceptance message or the call hold execution message described above, various methods including information for performing a call hold function may be used in addition to the Re-INVITE message. In addition, as a method for transmitting event information such as a call pending event message and a call cancellation event message, methods such as Re-INVITE, REFER, SUBSCRIBE, NOTIFY, and MESSAGE including the corresponding event information may be used.

FIG. 5A is a state machine illustrating a state transition of an IP terminal receiving a call hold service according to an embodiment of the present invention.

Referring to FIG. 5A, in state 501, the first call and the second call maintain IDLE / IDLE states, respectively. In state 501, the state information is updated to state 502 when the user hooks off the handset of the IP terminal (or presses the hook off button means of the speaker phone). In state 502, the first call is a DIAL and the second call is an IDLE state. If a hook FLASH or a redial event is input from the user in the state 502, all call connection information collected is cleared, and the state transitions to the state 502 of collecting the connection information again. When the Hook ON event is input from the user in the state 502, all the call connection information collected may be cleared, and the state information of the first call may be changed to IDLE to become the state 501. In the state 502, when the call connection request message for the first call is transmitted, the state 503 transitions to the SEIZE / IDLE state. Receiving a call connection response message from the IP exchange system in state 503 transitions to state 504 and enters the BUSY / IDLE state. In the state 504, if a call hold event (such as a user's hook FLASH input or a special function key provided in an IP terminal such as a FLASH key or a call hold key) is input from the user in the state 504, the IP terminal receives a call for the first call. The call hold event message is delivered to the IP switch system, and the IP switch system sends a call hold accept message for the call hold event message to the IP terminal. The IP terminal receives the call hold acceptance message and changes the first call to the HOLD state and the second call to the DIAL state (state 505). In state 505, connection information (DTMF tones, etc.) for the second call is collected, and a call connection request message for the second call is transmitted to the IP exchange system so that the first call is HOLD and the second call is SEIZE state ( 506). Receive a call connection response message for the second call from the IP exchange system and transition to state 507. Through the operation of the state machine, a call with the first party through the first call may be suspended, and a call with the second party through the second call may be performed.

FIG. 5B is a state machine illustrating a state transition of an IP terminal receiving a call waiting service according to an embodiment of the present invention.

Since the states 511 to 514 are the same as the states 501 to 504 of FIG. 5A, description thereof is omitted. Referring to FIG. 5B, when a call waiting situation occurs in state 514, a call connection request for a second call is received from a second party and transitions to state 515. In state 515, the IP terminal sends a call hold event message for the first call to the IP exchange system, receives a call hold accept message for the first call from the IP switch system, and connects the call to the second call. By sending a response message to the IP exchange system, the first call becomes HOLD / second call BUSY (516). Through the operation of the state machine, the call with the first party through the first call is put on hold and the call with the second party through the second call can be performed.

5C is a state machine illustrating a state transition of an IP terminal receiving a call transfer service according to an embodiment of the present invention. The state machine shown in FIG. 5C illustrates a state performed when a call establishment request is received from a first party in an IDLE / IDLE state unlike in FIGS. 5A and 5B.

In state 521, the state information of the first call and the second call becomes IDLE / IDLE. When there is a call connection request from the first party, the IP terminal receives a call connection request message for the first call transmitted from the first party from the IP exchange system, and the first call has a RING / second call in IDLE state ( 522). When an event such as Hook OFF of the user is input in state 522, the IP terminal transmits a call connection response message to the IP exchange system, and the first call BUSY / second call transitions to IDLE state 523. The state 523 means a state in which a call between a user and a first counterpart is connected. Receives a call hold event (Hook FLASH, FLASH button, or a special function key such as a call hold button) from the user in state 523, sends a call hold event message corresponding to the call hold event to the IP exchange system, The first call transitions to HOLD / second call to DIAL state 524 by receiving a call hold accept message from the exchange system. In state 524, the connection information of the second party is collected from the user, and a call connection request message for the second party is transmitted to the IP exchange system to transition to state 525. FIG. In state 525, a call connection request response message sent from the second party is received from the IP exchange system and transitions to state 526 of first call HOLD / second call BUSY. In state 526, the state transitions to state 521 by transmitting call termination request messages for the first call and the second call, and the first party and the second party can make a call through the IP exchange system. have.

One example of the call transfer service shown in FIG. 5C is merely illustrative, and it is possible to perform a call transfer service in the state 525 of FIG. 5C, which is the same as the state 506 of the state machine shown in FIG. 5A. Will be self-explanatory.

FIG. 5D is a state machine illustrating a state transition of an IP terminal receiving a conference call or a three way call service according to an embodiment of the present invention.

Since the states 531 to 534 are the same as the states 501 to 504 of FIG. 5A, description thereof is omitted. Referring to FIG. 5D, when a third party call or a conference call is added by adding a second party or the like to the call in the state 534, a call hold event message is input from the user and a call hold event message for the call hold event is received. To the IP exchange system. A call hold accept message for the first call is received from the IP exchange system and the first call HOLD / second call DIAL state 535 is entered. In state 535, the connection information of the second party who wants to make a call through the second call is collected, and the call connection request message for the second call is transmitted to the IP exchange system, and the state transitions to state 536. In state 536, a call connection response message for the second call transmitted from the second party is received from the IP switch system, and the state 537 is the first call HOLD / second call BUSY. Sends a conference call event message for the conference call event (special function keys such as Hook FLASH, FLASH button, conference call button, etc.) input from the user in state 537 to the IP exchange system, and the call from the IP exchange system to the second call. Receives the call termination message for the first call and the call hold release message for the first call and transitions back to state 534.

In state 537, the IP exchange system processes the first call between the user and the first party in a held state and processes the second call between the user and the second party in a call state. The IP exchange system may receive a conference call event message for the conference call event input from the user in the hold state of the first call and the call state of the second call. According to another embodiment of the present invention, when the IP terminal is in the state 535, the IP exchange system may transmit the conference call event message to the second counterpart along with the call connection request message for the second call. have. In this case, information that the user wishes to make a conference call or a three-way call may be stored in the IP exchange system. The IP exchange system queries the user's call service details to determine whether to provide a conference call or a three-way call service, and terminates the second call of the user. The IP exchange system assigns the mixer means necessary for a three-way or conference call and sends a media channel reset message (which may be a Re-INVITE message in the case of SIP) containing the media channel information for the mixer. , And to the second party. The user, the first counterpart, and the second counterpart may connect to the mixer corresponding to the media channel information to perform a conference call or a three-way call.

In addition, embodiments of the present invention include computer-readable media containing program instructions for performing various computer-implemented operations. The program recorded on the computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. The media may be those specially designed and constructed for the purposes of the present invention, or they may be of the kind well-known and available to those having skill in the computer software arts.

While specific embodiments of the present invention have been described so far, various modifications are possible without departing from the scope of the present invention.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims below, but also by the equivalents of the claims.

As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above-described embodiments, which can be variously modified and modified by those skilled in the art to which the present invention pertains. Modifications are possible.

Accordingly, the spirit of the present invention should be understood only by the claims set forth below, and all equivalent or equivalent modifications thereof will belong to the scope of the present invention.

According to the present invention, there is an advantage in that a variety of call services can be provided in a low-cost IP terminal having only minimal functions.

In addition, according to the present invention, there is provided an IP terminal capable of minimizing the function of the IP terminal and receiving a call service in the IP exchange system.

In addition, according to the present invention, when an additional call service is developed, an IP terminal is provided which can be provided with the corresponding service only by upgrading the IP switch system without changing the IP terminal.

In addition, according to the present invention, by minimizing the function of the IP terminal, by making the most of the function of the IP exchange system, it is necessary to have a mixer device for a call service or an additional device for reproducing the held sound in the IP terminal. IP terminal is provided.

In addition, according to the present invention, by minimizing the function of the IP terminal has the advantage of lowering the manufacturing cost of the IP terminal, thereby activating the call service using the IP network.

Claims (12)

In the operation method of the IP terminal for receiving a call service from the IP exchange system, Maintaining a state manager for storing state information for the first and second calls, wherein the state information for the first and second calls is IDLE; Changing state information of the first call to DIAL in response to a user inputting a Hook OFF; Transmitting a call connection request message to a first party through the first call to the IP exchange system, and status information of the first call stored in the state manager in response to receiving a call connection response message for the call connection request message. Changing to BUSY; Receiving a call hold event from the user and transmitting a call hold event message corresponding to the call hold event to the IP exchange system; Receiving a call hold acceptance message for the call hold event from the IP exchange system, changing state information of the first call stored in the state manager to HOLD, and changing state information of the second call to DIAL; Receiving connection information about a second party from the user, and transmitting a call connection request message to the IP exchange system to change the state information of the second call to SEIZE; And Receiving a call connection response message from the IP exchange system and changing state information of the second call to BUSY Method of operation of an IP terminal comprising a. In the operation method of the IP terminal for receiving a call service from the IP exchange system, Maintaining a state manager for storing state information for the first and second calls, wherein the state information for the first and second calls is IDLE; Changing state information of the first call to DIAL in response to a user inputting a Hook OFF; Transmitting a call connection request message to a first party through the first call to the IP exchange system, and status information of the first call stored in the state manager in response to receiving a call connection response message for the call connection request message. Changing to BUSY; Receiving a call connection request message from a second party from the IP exchange system and changing state information of the second call to RING; Receiving a call hold event from the user and transmitting a call hold event message for the call hold event to the IP exchange system; And Receiving a call hold accept message for the call hold event from the IP exchange system, change the state information of the first call stored in the state manager to HOLD, and change the state information of the second call in response to the call connection request message. Steps to change to BUSY Method of operation of an IP terminal comprising a. In the operation method of the IP terminal for receiving a call service from the IP exchange system, Maintaining a state manager for storing state information for the first and second calls, wherein the state information for the first and second calls is IDLE; Receiving, by the IP exchange system, a call connection request message transmitted from a first party through the first call, and changing state information of the first call to RING; Changing the state information of the first call to BUSY in response to a Hook OFF input of a user; Receiving a call hold event from the user and sending a call hold event message for the call hold event to the IP exchange system; Receiving a call hold acceptance message for the call hold event from the IP exchange system, changing state information of the first call stored in the state manager to HOLD, and changing state information of the second call to DIAL; Receiving connection information about a second party from the user, and transmitting a call connection request message to the IP exchange system to change state information of the second call to SEIZE; And Receiving a call connection response message from the IP exchange system and changing state information of the second call to BUSY Method of operation of an IP terminal comprising a. In the operation method of the IP terminal for receiving a call service from the IP exchange system, Maintaining a state manager for storing state information for the first and second calls, wherein the state information for the first and second calls is IDLE; Receiving, by the IP exchange system, a call connection request message transmitted from a first party through the first call and changing state information of the first call to RING; Changing the state information of the first call to BUSY in response to a Hook OFF input of a user; Receiving a call connection request message from a second party from the IP exchange system and changing state information of the second call to RING; Receiving a call hold event from the user and transmitting a call hold event message for the call hold event to the IP exchange system; And Receiving a call hold accept message for the call hold event from the IP exchange system, change the state information of the first call stored in the state manager to HOLD, and change the state information of the second call in response to the call connection request message. Steps to change to BUSY Method of operation of an IP terminal comprising a. The method according to claim 1 or 3, If a call connection corresponding to the call connection request message sent to the IP exchange system fails, the call holding release message for the first call is received from the IP exchange system and the state information of the first call is BUSY. Changing the status information of the second call to IDLE Method of operation of an IP terminal comprising a. The method according to claim 1 or 3, Transmitting a call connection cancel message to the IP exchange system when the user cancels the call establishment request; And Receiving a call hold release message for the first call from the IP exchange system and changing the state information of the first call to BUSY and the state information of the second call to IDLE; Method of operation of an IP terminal comprising a. The method according to any one of claims 1 to 4, The call holding event is a hook flash input or a predetermined special function key input provided to the IP terminal. The method according to any one of claims 1 to 4, And the IP terminal is a gateway device between a public switched telephone network (PSTN) and an IP network. A computer-readable recording medium having recorded thereon a program for executing the method of any one of claims 1 to 4. An IP terminal for receiving a call service from an IP exchange system, A state manager which stores state information about the first and second calls; A call processor for controlling call processing of the IP terminal according to the state information of the first call and the second call stored in the state manager; And Communication interface unit for transmitting the call data according to the first call and the second call in accordance with the control signal of the call processing control unit Including, The call processing unit, In response to the Hook OFF input of the user, the state information of the first call is changed to DIAL, and a call connection request message to the first party is transmitted to the IP exchange system through the first call, and the IP exchange system is sent from the IP exchange system. Receives a call connection response message, changes the state information of the first call stored in the state manager to BUSY, receives a call hold event from the user, and transmits a call hold event message for the call hold event to the IP exchange system. Receiving the call hold acceptance message for the call hold event from the IP exchange system, changing the state information of the first call stored in the state manager to HOLD, and changing the state information of the second call to DIAL; Receiving connection information for a second party from a user, and receiving the IP exchange system. Send a call connection request message to change the state information of the second call to SEIZE, and receive a call connection response message from the IP exchange system to change the state information of the second call to BUSY. terminal. An IP terminal for receiving a call service from an IP exchange system, A state manager which stores state information about the first and second calls; A call processor for controlling call processing of the IP terminal according to the state information of the first call and the second call stored in the state manager; And Communication interface unit for transmitting the call data according to the first call and the second call in accordance with the control signal of the call processing control unit Including, The call processing unit, In response to the Hook OFF input of the user, the state information of the first call is changed to DIAL, and a call connection request message to the first party is transmitted to the IP exchange system through the first call, and the IP exchange system is sent from the IP exchange system. Receives a call connection response message, changes the state information of the first call stored in the state management unit to BUSY, receives a call connection request message from a second party from the IP exchange system, and converts the state information of the second call to RING. Change, receive a call hold event from the user, send a call hold event message for the call hold event to the IP switch system, and receive a call hold accept message for the call hold event from the IP switch system; Change the status information of the first call stored in the status manager to HOLD And change state information of the second call to BUSY in response to the call connection request message. The method according to claim 10 or 11, wherein The IP terminal is a gateway device between a public switched telephone network (PSTN) and the IP network.

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