KR100912201B1 - Fax call processing method and device by megaco protocol - Google Patents

Abstract

The present invention relates to a method and a device for processing a fax call using the MEGACO / H.248 protocol. In the fax call processing using the MEGACO protocol, a soft switch collects codec information of a calling terminal and a called terminal to establish a media session. By selecting the necessary codec, it is possible to stably provide setting of a fax call and transmission / reception of fax communication between the calling terminal and the called terminal. Therefore, according to the present invention, it is possible to reduce the probability of failure in fax processing sensitive to time delay and to eliminate the complexity of SoftSwitch involvement in all the fax processing. The stability and efficiency of the treatment can be further improved.

MEGACO, Fax, Codec, Call, Media Session

Description

FAX CALL PROCESSING METHOD AND DEVICE BY MEGACO PROTOCOL}

The present invention relates to a method and apparatus for processing a fax call using the MEGACO protocol. More particularly, the present invention relates to a fax using the MEGACO protocol, which enables fax communication by selecting and converting a media codec between a sending and receiving terminal and a receiving terminal. A call processing method and apparatus.

Recently, as communication networks continue to evolve, there is a growing interest in Next Generation Networks (NGNs) or Broadband Convergence Networks (NGNs), which replace legacy communication networks such as PSTNs. The next generation network or broadband communication network integrates all communication networks such as general telephone network (PSTN), asynchronous transmission (ATM) network, frame relay (FR) network, private network, and wireless communication network into a packet-based common network. It is known as a voice-video-data integrated network to provide a flexible and open network solution and a variety of applications, as well as reducing deployment and operating costs. As the network evolves and the demand for the user's communication service continues to increase, various multimedia communication services that cannot be provided in the legacy legacy communication network will be provided in the next generation communication network.

In NGN, since H.323 network is already established, interworking with H.323 network is required as an essential function, and MEGACO / H.248 is required by service providers.

On the other hand, softswitch refers to a system that controls a call based on a packet network in response to the role of an existing network switch in a next-generation network, regardless of the protocol supported by the system, and individual or combined functions of systems that play a role of call control. It is provided with various names such as Media Gateway Controller, Call Server, or Call Agnets. On the other hand, regardless of the protocol (H.323, SIP, MGCP, MEGACO / H.248) is used in the meaning of the switch to control through the software to control the call based on the packet (Packet) network.

However, in the conventional FAX call processing method, there is a complexity that SoftSwitch must be involved in all processes of FAX tones, and when a FAX Tone is detected, a signal is transmitted or a fax communication is performed. Since the entire process of negotiation was handled as an event and a signal, there was a disadvantage in that the probability of a failure was high in a fax processing sensitive to time delay.

The present invention has been made to improve the prior art as described above, during the fax call processing using the MEGACO protocol, the soft switch collects the fax codec information of the calling terminal and the called terminal to select the codec necessary for the establishment of the media session Thus, by setting up a fax call and sending / receiving fax communication between the calling terminal and the called terminal reliably, it is possible to reduce the probability of a failure during the fax processing sensitive to time delay, It aims to improve the stability and efficiency of fax call processing by eliminating the complexity that SoftSwitch is involved in.

In order to achieve the above object and to solve the problems of the prior art, the method for fax call processing using the MEGACO protocol according to one aspect of the present invention, the softswitch receiving a notification signal and a response signal for the fax call from the calling terminal and the called terminal If the softswitch receives the fax codec information of the called terminal from the called terminal and transmits it to the calling terminal, the softswitch receives the fax codec information of the calling terminal and delivers it to the called terminal and And controlling, by the soft switch, fax call connection by using the fax codec information of the calling terminal and the fax codec information of the called terminal.

According to another aspect of the present invention, the transmitting terminal transmits a notification signal for a fax call, the soft switch receiving the notification signal from the calling terminal and forwarding to the called terminal, the called terminal is the Transmitting a response signal to the notification signal and transmitting the response signal from the called terminal to the calling terminal by the soft switch.

According to another aspect of the present invention, the step of controlling the fax call connection, the soft switch receives the fax codec information of the called terminal from the called terminal provided to the calling terminal, the calling terminal from the calling terminal Receives the fax codec information and provides it to the called terminal, and controls the fax call connection by using a common fax codec of the called terminal and the calling terminal.

According to another aspect of the invention, the notification signal is a calling tone (Calling Tone), the response signal is an answer tone (Answer Tone), the notification signal and the response signal is configured using a NOTIFY command.

According to another aspect of the invention, the fax codec is at least one of T.38 and G711 (PCMA, PCMU).

According to another aspect of the present invention, when the fax call connection is terminated, the method further comprises the step of switching to a standby state capable of a voice call call.

According to the present invention, during the fax call processing using the MEGACO protocol, the soft switch collects codec information of the calling terminal and the called terminal, selects the codec necessary for setting up the media session, and sets up the fax call between the calling terminal and the called terminal. The transmission and reception of fax communication can be provided stably.

Therefore, it lowers the probability of failure in fax processing that is sensitive to time delay, and eliminates the complexity of SoftSwitch in all processes of fax processing, thereby ensuring the stability and efficiency of fax call processing. Can be improved more.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings and the contents described in the accompanying drawings, but the present invention is not limited or limited to the embodiments. Like reference numerals in the drawings denote like elements.

Although the present invention has been described by way of example of a fax call processing method using the MEGACO protocol, it is also applicable to the fax call processing method using the H.248 protocol.

Figure 1a is a view showing a fax call processing method using the MEGACO protocol according to an example of the present invention from the perspective of the entire system, Figure 1b is a fax call using a MEGACO protocol according to another example of the present invention from the perspective of the entire system 1C is a view showing a processing method, and FIG. 1C is a view showing a fax call processing method using the MEGACO protocol according to another example of the present invention from the viewpoint of the entire system.

Media Gateway Control (MEGACO) refers to a signaling control protocol used between a Media Gateway and a Media Gateway Controller in a VoIP network.

In the present invention, a terminal (EP) such as the calling terminal 110 and the called terminal 130 is a logical term, for example, an IP terminal such as a facsimile (fax). Or the like.

Each terminal (EP) can communicate with other terminals through a media / call connection control device such as a soft switch (SSW: SoftSwitch), and with the soft switch (SSW: SoftSwitch) for signaling for a fax service. Call processing with other terminals is performed through communication.

The soft switch according to the present invention is capable of call processing through the MEGACO protocol, so that a gatekeeper supporting H.323, a gateway controller supporting MGCP, a media gateway controller (MGC), and SIP are supported. Like SIP server, it provides the function to play the role of call control.

Each terminal EP may perform fax communication with another terminal through the media / call connection control apparatus 120 as described above.

In order to transmit a fax to the called terminal 130 through a session based on the IP protocol from the calling terminal EP to the called terminal EP 130, the codecs must match each other.

To this end, the calling terminal 110 and the called terminal 130 issues the IP information and codec information available in the terminal to the soft switch 120. Such information is called a media session description message, and the protocol for expressing it is called a Session Description Protocol (SDP).

Through the SDP Offer / Answer Model, the softswitch may receive the codec information capable of fax communication from each terminal and perform fax call processing.

FIG. 1A illustrates a method of setting up a voice call before setting up a fax call according to the present invention.

In order to control the media connection of the calling terminal 110, the soft switch 120 transmits a media stream generation command ADD to the calling terminal 110, and as a reply signal, a voice codec of the calling terminal 110. Receives the information sdp_a and delivers the media stream generation command ADD including the codec information of the calling terminal 110 to the called terminal 130. In response to the codec information of the calling terminal 110 transmitted to the called terminal 130, the called terminal 130 transmits the voice codec information (sdp_b) of the called terminal 130 to the soft switch 120, soft switch The receiving unit 120 transmits the voice codec information sdp_b of the called terminal 130 to the calling terminal through a media stream change command MODIFY, and the calling terminal 110 transmits the soft code 120 to the calling terminal. Answer Subsequently, when the called terminal 130 notifies the soft switch 120 that the call by setup of the voice call is ready through the notification signal command NOTIFY, the soft switch 120 responds to the notification. 130, and sets up a call to the calling terminal 110 to complete the voice call setup.

In the voice call setup state as described above, in order to set up a fax call, as shown in FIG. 1B, the originating terminal 110 notifies the soft switch 120 of the start of the fax call through the notification signal command NOTIFY. The receiving terminal 110 notifies the soft switch 120 of the start of the fax call through the notification signal command NOTIFY and receives the response.

Thereafter, the soft switch 120 transmits a media stream change command (MODIFY) to the called terminal 130 to set up the fax call, receives the fax codec information sdp_B 'of the called terminal 130, and sends the calling terminal 110. ) Transmits the media stream change command MODIFY including the fax codec information sdp_B 'of the called terminal 130 to receive the fax codec information sdp_A' of the called terminal 110. In addition, the soft switch 120 transmits a media stream change command MODIFY including the fax codec information sdp_A 'of the calling terminal 110 and receives a response thereto.

As described above, the fax codec information of the calling terminal 110 and the called terminal 130 is transmitted and received under the control of the soft switch 120, and fax communication is performed by selecting a codec to be used for fax communication by setting up a fax call. .

In this case, in the present invention, T.38 or G711 may be used as the fax codec. The notification signal command NOTIFY may be a calling tone, and the response signal command may be an answer tone.

Then, in order to return to the setting of the voice call from the setting of the fax call, as shown in Figure 1c, the destination terminal 130 transmits a notification signal command (NOTIFY) to the soft switch 120, and receives a response thereto, The soft switch 120 transmits a media stream change command MODIFY to the called terminal 130 to receive voice codec information sdp_b 'of the called terminal 130. Thereafter, the soft switch 120 transmits the received voice codec information sdp_b 'of the called terminal 130 to the calling terminal 110, and includes a response including the voice codec information sdp_a' of the calling terminal 110. And the voice codec information sdp_a 'of the calling terminal 110 is transferred to the called terminal 130 to complete the setup of the voice call.

2 is a block diagram of an apparatus for controlling media connection according to an example of the present invention.

As shown in FIG. 2, the fax call processing apparatus (soft switch) using the MEGACO protocol according to the present invention includes a receiver 210, a controller 220, a transmitter 230, and the like.

The receiving unit 210 receives a notification signal for a fax call from the calling terminal and the called terminal, and receives the fax codec information of the called terminal and the fax codec information of the called terminal from the called terminal. In addition, the receiving unit 210 receives a notification signal from the calling terminal and serves to receive a response signal from the called terminal.

The transmitting unit 230 transmits the fax codec information of the called terminal received by the receiving unit 210 to the calling terminal, and transmits the fax codec information of the calling terminal received by the receiving unit to the called terminal. In addition, the transmitter 230 transmits the received notification signal to the called terminal, and transmits the received response signal to the calling terminal.

The controller 220 controls the fax call connection by using the fax codec information of the calling terminal and the fax codec information of the called terminal. Particularly, the control unit 220 controls to receive the fax codec information of the called terminal from the called terminal and provides it to the calling terminal, and controls to receive the fax codec information of the calling terminal from the calling terminal and provide it to the called terminal. Fax call connection is controlled using a common fax codec of the called terminal and the calling terminal.

In addition, after the setup of the fax call is completed, the controller 220 controls the voice call call to be switched to a standby state.

Accordingly, the soft switch 120 can stably provide the setting of the fax call and the transmission / reception of the fax communication between the calling terminal and the called terminal through a codec selection procedure during the fax call processing using the MEGACO protocol.

3 is a flowchart illustrating a fax call processing method using the MEGACO protocol according to an example of the present invention.

When the soft switch receives the notification signal and the response signal for the fax call from the calling terminal and the called terminal (S310), the soft switch receives the fax codec information of the called terminal from the called terminal and transmits it to the calling terminal. (S320).

Thereafter, the soft switch receives the fax codec information of the calling terminal and delivers it to the called terminal (S330).

The soft switch controls the fax call connection by using the fax codec information of the calling terminal and the fax codec information of the called terminal (S340), so that the fax call is connected (S350).

The facsimile connection is performed by the soft switch, which receives the fax codec information of the called terminal from the called terminal and provides it to the calling terminal, and receives the fax codec information of the calling terminal from the calling terminal and provides it to the called terminal. And, it is made by controlling the fax call connection by using a common fax codec of the called terminal and the calling terminal.

Thereafter, when the fax call connection is terminated, the voice call call is returned to the enabled state (S360).

At this time, the fax codec may be one of T.38 or G711 (PCMA, PCMU).

4 is a flowchart illustrating a fax call processing method using the MEGACO protocol according to another embodiment of the present invention, in which a soft switch receives a notification signal for a fax call from a calling terminal and a called terminal in more detail (S310). It is explained.

As shown in Figure 4, when the calling terminal transmits a notification signal for a fax call (S410), the soft switch receives the notification signal from the calling terminal and delivers it to the called terminal (S420).

Thereafter, when the called terminal transmits a response signal to the notification signal (S430), the soft switch receives the response signal from the called terminal and delivers it to the calling terminal.

Through this process, the soft switch receives a notification signal for a fax call from the calling terminal and the called terminal, and the notification signal is configured using the "NOTIFY" command.

In this case, the notification signal is a calling tone and the response signal is an answer tone.

Meanwhile, embodiments of the present invention include a computer readable medium including program instructions for performing various computer-implemented operations. For example, computer-readable media containing program instructions on which the invention is implemented are also aspects of the invention. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. The medium or program instructions 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. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks, such as floppy disks. Magneto-optical media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. The medium may be a transmission medium such as an optical or metal wire, a waveguide, or the like including a carrier wave for transmitting a signal specifying a program command, a data structure, or the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like.

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.

1A is a diagram illustrating a fax call processing method using the MEGACO protocol according to an example of the present invention from the viewpoint of the entire system.

Figure 1b is a view showing a fax call processing method using the MEGACO protocol according to another example of the present invention in terms of the entire system.

Figure 1c is a view showing a fax call processing method using the MEGACO protocol according to another example of the present invention from the perspective of the entire system.

2 is a block diagram of a fax call processing apparatus (soft switch) using the MEGACO protocol according to an example of the present invention.

3 is a flowchart illustrating a fax call processing method using the MEGACO protocol according to an example of the present invention.

4 is a flowchart illustrating a fax call processing method using the MEGACO protocol according to another exemplary embodiment of the present invention.

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

110: calling terminal

120: soft switch

130: called terminal

210: receiver

220: control unit

230: transmitter

Claims (12)

Setting up, by the softswitch, the voice codec information received from the calling terminal to the called terminal and transmitting the voice codec information received from the called terminal to the calling terminal to set up a voice call between the calling terminal and the called terminal; Receiving, by the softswitch, a notification signal and a response signal for a fax call from the calling terminal and the called terminal; Receiving, by the soft switch, the fax codec information of the called terminal from the called terminal and transmitting the received fax codec information to the calling terminal; Receiving, by the soft switch, the fax codec information of the calling terminal and transmitting the received fax codec information to the called terminal; Controlling, by the softswitch, to establish a fax call connection by using common fax codec information among the fax codec information of the calling terminal and the fax codec information of the called terminal. The fax codec information includes T. 38 and G711 ( PCMA, PCMU); And When the fax call connection is terminated, the soft switch delivers the voice codec information received from the called terminal to the calling terminal, and delivers the voice codec information received from the calling terminal to the called terminal. Transitioning to a state where voice calls can be made between called terminals Fax call processing method using a MEGACO protocol comprising a. The method of claim 1, Receiving a notification signal and a response signal for a fax call, Receiving, by the softswitch, a notification signal for the fax call from the originating terminal and transmitting the notification signal to the called terminal; And Receiving, by the soft switch, a response signal to the notification signal from the called terminal and transmitting the received signal to the calling terminal; Fax call processing method using a MEGACO protocol comprising a. The method of claim 1, The step of setting up a voice call between the calling terminal and the called terminal, Transmitting, by the soft switch, voice codec information of the calling terminal to the called terminal through a media stream generation command; Transmitting, by the soft switch, voice codec information of the called terminal to the calling terminal through a media stream change command; And Receiving, by the softswitch from the destination terminal, a notification signal for preparation for setup of a voice call and responding to the notification signal; Fax call processing method using a MEGACO protocol comprising a. The method of claim 2, The notification signal is a calling tone (Calling Tone), the response signal is an answer tone (Answer Tone), characterized in that the fax call processing method using the MEGACO protocol. The method of claim 2, The notification signal and the response signal, Fax call processing method using the MEGACO protocol, characterized in that configured using the NOTIFY command. delete The method of claim 1, The step of switching to a voice call call is available, Receiving, by the softswitch, a notification signal for terminating the connection of a fax call from the called terminal; Transmitting, by the soft switch, voice codec information of the called terminal to the calling terminal through a media stream change command; And Transmitting, by the soft switch, voice codec information of the calling terminal to the called terminal through the media stream change command; Fax call processing method using a MEGACO protocol comprising a. In the fax call processing apparatus using the MEGACO protocol, A receiving unit for receiving a notification signal and a response signal for a fax call from a calling terminal and a called terminal, and receiving fax codec information of the called terminal and fax codec information of the calling terminal from the called terminal; A transmitter for transmitting the fax codec information of the called terminal received by the receiver to the calling terminal, and transmitting the fax codec information of the calling terminal received by the receiver to the called terminal; And A control unit for controlling a fax call connection by using the common fax codec information among the fax codec information of the calling terminal and the fax codec information of the called terminal. The fax codec information includes at least one of T. 38 and G711 (PCMA, PCMU). Which one Including, The fax call processing device, Voice codec information received from the calling terminal is transmitted to the called terminal before connecting the fax call, and voice codec information received from the called terminal is delivered to the calling terminal, thereby making a voice call between the calling terminal and the called terminal. Set up the When the fax call connection is terminated, the voice codec information received from the called terminal is delivered to the calling terminal, and the voice codec information received from the calling terminal is delivered to the called terminal, thereby providing voice between the calling terminal and the called terminal. Fax call processing apparatus using the MEGACO protocol, characterized in that the call is switched to the available state. The method of claim 8, The receiving unit receives the notification signal from the calling terminal, receives a response signal from the called terminal, And the transmitter transmits the received notification signal to the called terminal, and transmits the received response signal to the calling terminal. The method of claim 8, The fax call processing device, Delivering voice codec information of the calling terminal to the called terminal through a media stream generating command; Delivering voice codec information of the called terminal to the calling terminal through a media stream change command; Receiving a notification signal for preparation for setting up a voice call from the called terminal and setting up a voice call in response to the notification signal. The method of claim 8, The fax call processing device, Receiving a notification signal for terminating the connection of a fax call from the called terminal; Delivering voice codec information of the called terminal to the calling terminal through a media stream change command; The apparatus for processing a fax call using the MEGACO protocol, wherein the voice codec information of the calling terminal is transmitted to the called terminal through the media stream change command. The method of claim 8, The fax call processing device, Fax call processing apparatus using the MEGACO protocol, characterized in that it comprises a soft switch (SoftSwitch).

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