KR20040015959A - Method for transmitting access gateway subscribe line information using media gateway control protocol - Google Patents

Abstract

PURPOSE: A method for transmitting access gateway subscriber line information by using an MGCP(Media Gateway Control Protocol) is provided to transmit voice services for subscribers, connected to an access gateway interfaced with a soft switch through an MGCP, through an ATM network. CONSTITUTION: An access gateway(200) consists of a subscriber line device part(210), a time switch(220), a DTMF signal generation part(230), a tone signal generation part(240), and a main processor part(250). The subscriber line device part(210) is connected with the first and second subscribers(300,400). The DTMF signal generation part(230) generates a DTMF signal. The tone signal generation part(240) generates a tone signal. The main processor part(250) is formed between an IP network(100), the subscriber line device part(210), the time switch(220), the DTMF signal generation part(230), and the tone signal generation part(240). The main processor(250) provides a subscriber line information transfer and control function, an ATM voice channel information transfer function, an ATM resource control function, and a DTMF/tone equipment control/connection function by using an MGCP.

Description

Method for transmitting access gateway subscribe line information using media gateway control protocol

The present invention relates to an asynchronous transmission mode based voice service method using a media gateway control protocol. In particular, the present invention relates to an asynchronous transmission mode network for a voice service for a subscriber mounted in an access gateway interworked with a soft switch and a media gateway control protocol (MGCP). The present invention relates to a method for transmitting access gateway subscriber line information using a media gateway control protocol.

Hereinafter, a voice service using a media gateway control protocol according to the prior art will be described with reference to the accompanying drawings.

1 is a block diagram of an Internet Protocol (IP) voice service apparatus using a media gateway control protocol according to the prior art.

Internet protocol voice service apparatus using a media gateway control protocol according to the prior art is basically the soft switch 10 and the first and second media gateways 20 and 30 and the first and second media, respectively, as shown in FIG. Media gateway subscribers 40, 50 connected to gateways 20, 30.

Conventionally, a media gateway control protocol (hereinafter abbreviated as MGCP) is used between the first and second media gateways 20 and 30 to provide voice services to subscribers 40 and 50 of the media gateway. IP network 60 was used as the voice packet transmission network.

At this time, as a media gateway based on the IP network 60, the subscribers 40 and 50 connected to the media gateways 20 and 30 and the media gateways in the MGCP message for setting the IP voice packet call of the media gateway subscribers 40 and 50, respectively. Voice channel information, that is, an IP address and a port number, are transmitted to each other, and the MGCP message is analyzed to control the subscriber line and the IP packet transmission equipment to enable voice transmission to the subscribers 40 and 50.

Here, the soft switch 10 serves as a bridge for other signaling types and a general platform for controlling various types of media gates. The soft switch 10 serves as a switch in the existing packet switching network as a higher concept of the gatekeeper of the H.323 recommendation. Software that functions as an integrated private exchange on the Internet that can collectively manage communication information such as voice, data, and video.

In this prior art, the calling media gateway (for example, the first media gateway 20) and the called media gateway (for example, the second media gateway 30) are used to set the voice packet path as the voice call path information. Voice channel information (IP address, port number) is transmitted to the soft switch 10 using the MGCP message.

The soft switch 10 transmits the voice channel information of the first media gateway 20 received through the MGCP to each media gateway (for example, the second media gateway 30) to be connected. Accordingly, each media gateway controls its own IP packet transmission device with the received IP voice channel information. In addition, the subscriber call control function is performed so that voice is transmitted by connecting the IP packet transmission equipment and the subscriber line equipment of each media gateway.

That is, when an incoming call is attempted from the first subscriber 40 to the second subscriber 50, the first subscriber 40 of the first media gateway 20 and the second subscriber 50 of the second media gateway 30. In the voice call connection and subscriber control process, first, an IP address of the first media gateway 20 of the calling party is allowed to transmit and receive IP voice packets between the first media gateway 20 and the second media gateway 30. And a User Datagram Protocol (UDP) port for transmitting a voice packet of the first subscriber 40, and loads the corresponding information into the session description protocol description portion of the MGCP message, and transmits the corresponding information to the second media gateway 30 via the soft switch 10. To send).

The second media gateway 30, which is the called party, analyzes the received MGCP, classifies the IP address and the UDP port number of the first media gateway 20, sets the destination address value to control the IP device, and allocates the necessary resources. Prepare the connection.

Then, the second media gateway 30 controls the IP device to allocate its own IP address and UDP port for the second subscriber 50, and uses the MGCP to transmit the first through the soft switch 10. It transmits to the media gateway 20.

When the first media gateway 20 receives this and sets the IP address of the called-party second media gateway 30 and the UDP port of the second subscriber 50 as destination address values, the first media gateway 20 and the second media gateway 20 are set. The setting of the IP voice packet call path between the media gateways 30 is completed.

As such, based on the IP network, information on the IP address and the UDP port number of the device that is responsible for transmitting and receiving the IP packet in the media gateway 20 and 30 is used to transmit voice packets. Under the control, a voice call path was set between the media gateways 20 and 30.

Subsequently, voice packets are transmitted between the subscribers 40 and 50 through the IP network 60.

However, in the Internet protocol (IP) voice service according to the prior art, when using an IP network as a voice transmission network, there is a problem in that voice distortion and silence occur due to delay in packet transmission when traffic is congested in the IP network. .

The present invention has been made to solve the above problems, an access gateway subscriber line using a media gateway control protocol that can transmit voice services for subscribers mounted in an access gateway interworking with a soft switch and MGCP through an ATM network. Its purpose is to provide a method for transmitting information.

According to an aspect of the present invention for achieving the above object, the soft switch receiving the call origination of the calling party access gateway subscriber transmits the voice channel information of the calling party access gateway to the called party access gateway connected to the called party subscriber. The receiving side access gateway receiving the voice channel information transmits the voice channel information of the called access gateway to the calling access gateway, and transmits a ring tone to the calling subscriber. If the answer to the outgoing call comprises the step of connecting the voice packet equipment of the asynchronous transmission mode network between the source and destination access gateway.

Preferably, the source and destination access gateways provide subscriber line names for subscriber lines as access gateway internal station data so as to be distinguishable for each subscriber line connected thereto.

And when the call of the calling party, the called number by connecting the channel of the dual tone multi-frequency signal equipment to the channel corresponding to the line number under the control of the soft switch from the call attempt to the end of the subscriber line of the subscriber And provide a tone signal from a tone signal generator that generates a simultaneous tone signal, and transmits the called number and voice channel information of the calling access gateway to the soft switch using the subscriber line line name as an identifier.

Preferably, the source and destination access gateways control the actual subscriber line and tone signal generator, the dual tone multi-frequency signal generator and the asynchronous transmission mode voice packet transmission equipment for the subscriber under the control of the soft switch.

In addition, the source and destination access gateways receive events for the hook-off, hook-on, hook flash, and digits of the subscriber from the subscriber line device through inter-process communication, and use a common memory buffer to provide an MGCP stack processor. MGCP transmits and receives soft messages through IP interface and IP network through the IP interface and IP network, and the time switch, dual tone multi-frequency signal generator, tone signal generator Providing a time switch, a dual tone multi-frequency (DTMF) signal and a tone signal to subscribers, and a call controller for connecting a voice channel and a time switch of a voice packet transmission device to perform a voice call between subscribers; To the time switch, DTMF signal generator, tone signal generator, and subscriber line A device control unit which manages a resource, performs a channel management function via a time switch under control of a library call from the call control unit, and converts a message received from the call control unit to MGCP through an IP packet processing unit MGCP stack processing unit for transferring to the soft switch or by analyzing the MGCP received from the soft switch to convert the message used by the call control unit, and MGCP received from the MGCP stack processing unit recombines the UDP (User Datagram Protocol) packet And converts it into an IP packet and includes an IP interface that performs an IP packet transmission / reception function in association with an IP network.

Preferably, the source and destination access gateways each have a unique identifier that can be distinguished from the asynchronous transmission mode network, and each session of a media gateway control protocol message can be referred to each time the access gateway is driven and the voice channel is connected. Described in the decryption protocol unit, the step of connecting the voice packet equipment of the asynchronous transmission mode network, the source and destination access gateway is connected to the fixed virtual circuit of the asynchronous transmission mode, the gateway subscription The high level described in the session description protocol section of a media gateway control protocol message as a unique call identifier of the voice transmission / reception channel information between the calling party and the called party subscriber using the virtual path identifier and the virtual channel identifier as inter-channel voice transmission / reception channel information. Using the identifier wherein the asynchronous transfer mode and the step of generating the call identifier value at the time of voice channel resource, upon release the voice channel resource extinguishes the call identifier value.

Other objects, features and advantages of the present invention will become apparent from the detailed description of the embodiments with reference to the accompanying drawings.

1 is a block diagram of an Internet Protocol (IP) voice service apparatus using a media gateway control protocol according to the prior art

2 is a block diagram of a voice service apparatus for explaining subscriber line information transmission and call control in an asynchronous transmission mode based voice service method using a media gateway control protocol according to the present invention.

3 is a block diagram of a voice service apparatus for explaining voice channel delivery and ATM resource control in an asynchronous transmission mode based voice service method using a media gateway control protocol according to the present invention.

* Description of symbols on the main parts of the drawings *

100: IP network 200: access gateway

210: subscriber line device unit 220: time switch unit

230: DTMF signal generator 240: tone signal generator

250: main processor unit 260: ATM device unit

300,400 Subscriber 500: ATM Network

Hereinafter, an asynchronous transmission mode based voice service apparatus and method according to the present invention will be described with reference to the accompanying drawings.

The present invention generally uses the transmission of packets in controlling subscribers of an access gateway using MGCP, transferring information through voice calls between access gateways, and controlling voice packet transmission equipment and managing resources based on the transmitted information. It is to provide using ATM network, not public switched telephone network (PSTN) or IP network, and for this purpose, method of delivering voice channel information of ATM network to MGCP message, ATM resource management and control function, ATM equipment This chapter describes how to provide subscriber line, tone equipment, DTMF equipment connection and control functions.

In particular, subscriber line information transmission and call control function of the access gateway using MGCP, ATM voice channel information transmission method of the access gateway using MGCP, ATM resource control function, DTMF equipment of access gateway using MGCP, and control and connection of tone equipment Describe the function.

2 is a block diagram of a voice service apparatus for explaining subscriber line information transmission and call control functions in an asynchronous transmission mode based voice service method using a media gateway control protocol according to the present invention.

2 illustrates subscriber line information transfer and call control functions of an access gateway using MGCP to provide a voice service.

The access gateway 200 according to the present invention interworks with the IP network 100 to exchange soft switches (not shown) (see FIG. 1) with the MGCP to perform control functions for subscribers.

The access gateway 200 includes a subscriber line device 210 connected to the first and second subscribers 300 and 400, a time switch 220, and a dual tone multi-frequency signal generator for generating a dual tone multi-frequency signal ( 230, tone signal generator 240 and IP network 100 for generating a tone signal, subscriber line device unit 210, time switch 220, dual tone multi-frequency signal generator 230 and tone It is configured between the signal generator 240, subscriber line information transmission and call control function of the access gateway using the MGCP, ATM voice channel information transmission of the access gateway using the MGCP, ATM resource control function, DTMF of the access gateway using the MGCP It is composed of a main processor 250 that provides the control and connection of equipment, tone equipment.

Here, the call controller 254 of the main processor unit 250 may hook-off, hook-on, or hook-flash the subscribers 300 and 400 from the subscriber line device unit 210. And receiving an event for Digit as an interprocess communication (IPC), exchanging a message with the MGCP stack processor 252 using the memory buffer unit 253, and performing an IP interface unit 251 and IP. MGCP transmit and receive functions to and from the soft switch via the network (100).

In addition, the device (equipment) control unit 255 and the library call (Library call), a variety of equipment, that is, the time switch 220, dual tone multi-frequency (hereinafter abbreviated as DTMF) signal generator 230, tone signal generator Control 240 to provide subscribers 300,400 with time switches, dual tone multi-frequency (DTMF) signals and tone signals.

In addition, by connecting the voice channel and the time switch 220 of the voice packet transmission equipment performs a connection function as a voice call between the subscriber (300,400).

The device controller 255 manages resources related to the time switch 220, the DTMF signal generator 230, the tone signal generator 240, and the channel of the subscriber line, and controls the library call from the call controller 254. Receives the channel management function via the time switch 220.

The MGCP stack processor 252 converts the message received from the call controller 254 into MGCP and transmits the message to the soft switch, or analyzes and receives the MGCP received from the soft switch and converts the message into a message used by the call controller 254. do.

The IP interface unit 251 recombines the MGCP received from the MGCP stack processor 252 into UDP (User Datagram Protocol) packets and converts the MGCP back into IP packets to perform an IP packet transmission / reception function in conjunction with the IP network 100.

In addition, all of the subscriber lines 300 and 400 connected to the subscriber line device unit 210 of the access gateway 200 may be distinguished from the subscribers 300 and 400 by a soft switch (not shown in FIG. 1) and other access gateways. The subscriber line name for the subscriber 300,400 line is provided as internal station data of the access gateway 200. Here, the names of the subscriber 300 and 400 lines are referred to during the initialization process when the access gateway 200 is initially driven, and a new subscriber may be added or a name may be newly added or changed when the access gateway 200 is operated. Do.

When the subscriber 300 or 400 of the access gateway 200 attempts to make an outgoing call using the subscriber line name of the MGCP message as the identifier of the subscriber line, the line is controlled by the soft switch from the call attempt to the end of the line. By connecting the channel of the DTMF signal generator 230 to the channel corresponding to the number, and providing the incoming signal and the connection signal of the tone signal generator 240 at the same time, the called number and voice channel information of the calling access gateway (IP Address, port number) are transmitted by soft switch with subscriber line name as delimiter.

The soft switch translates the called party number to find the called party's access gateway and subscriber number based on the number translation result, and transmits the calling party's voice channel information (IP address, port number) to the called party's access gateway.

The called party's access gateway allocates the corresponding resources with the calling voice channel information, connects the ringing tone to the subscribers 300 and 400 who have requested to connect the call path, and then sends its voice channel information (IP address and port number) to the calling gateway. send.

After exchanging voice channel information between both access gateways, when the called access gateway subscriber answers the connection, it connects the corresponding subscriber line and ATM voice packet equipment to open a voice channel so that ATM voice packets can be transmitted and received between the two gateways. To provide a voice service between both subscribers.

As such, the information on the subscriber line is set to the voice call of the subscribers between the access gateways under the control of the soft switch using the subscriber line name in the MGCP message. The access gateway 200 exchanges the actual subscribers with the subscribers. The line and tone signal generator 240, the DTMF signal generator 230, and performs the function of controlling the ATM voice packet transmission equipment.

3 is a block diagram illustrating a voice channel information transmission method and an ATM resource control method in an asynchronous transmission mode based voice service method using a media gateway control protocol according to the present invention.

3 illustrates an ATM voice channel information transfer method and an ATM resource control function of an access gateway 200 using MGCP. The access gateway 200 according to the present invention uses an ATM network 500 as a voice packet transmission network. It is showing what it does.

The call controller 254 exchanges configuration information with a voice call between gateways through an MGCP message. At this time, it describes the ATM channel information to be allocated or released in the MGCP message, and performs resource management and control functions through a call of the access gateway through the ATM resource controller 256 and the IPC.

In addition, the call control unit 254 stores the NSAP address that can be distinguished from the ATM network 500 as station data by setting the access gateway 200 as a call as the source and destination address for setting the call between the access gateways. It transfers through MGCP message by reference and performs call function between access gateways during call control.

The ATM resource control unit 256 has a fixed virtual circuit (PVC), a virtual path identifier (VPI), a virtual channel identifier (VCI), and a call identifier (CID) value as station data. It performs the function of allocating and releasing ATM voice channel to the corresponding gateway when establishing and connecting ATM voice channel between gateways under the control through IPC. In addition, by performing the status management and resource management functions for the ATM equipment, and reports the lack of resources or failure.

In other words, when transmitting voice channel information and controlling ATM resources, the access gateway stores NSAP addresses and station data to distinguish each access gateway linked to the ATM network 500. The NSAP address value is the first access gateway. It is referenced not only during operation but also during voice channel connection and described in the session description protocol part of MGCP message.

In addition, the access gateways of the ATM network 500 are connected to a fixed virtual line (PVC) and use a virtual path identifier (VPI) and a virtual channel identifier (VCI) as voice transmission / reception channel information between access gateway subscribers.

The access gateway assigns ATM voice channel support by using the value of the virtual path identifier and the virtual path identifier as described in the session description protocol part of the MGCP message as the unique identifier call identifier (CID) of voice transmission / reception channel information between subscribers of the access gateway. By creating a time call identifier (CID) value or deleting the call identifier value when the voice channel is released, the ATM voice channel and resource management and control functions are performed.

At this time, as described above, various signals provided to the subscriber line in the access gateway are transferred to the access gateway using the MGCP message from the soft switch in each step of setting up the call path during the call path setting process for providing the voice service. In addition, the access gateway analyzes the MGCP message received from the soft switch to identify the corresponding subscriber line of the access gateway and, when there is a signal to be provided for the subscriber line, stores the corresponding signal type and connection in the subscriber information and simultaneously sends the signal. It classifies equipment for connection and immediately connects the signal equipment and subscriber line to provide a signal.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

As described above, the present invention performs a call control function for a subscriber line accommodated in an access gateway interworking with an ATM network, various signaling equipment control functions within the gateway, ATM resource management, and voice channel information control function using an MGCP message. It is effective to provide voice service of the same level as voice service provided to wireline subscribers accommodated in PSTN network using ATM network which is currently used as national backbone network in Korea.

Claims (7)

Transmitting, by the soft switch receiving the call origination of the calling party access gateway subscriber, the voice channel information of the calling party access gateway to the called party access gateway connected to the called party subscriber; The called access gateway receiving the voice channel information transmits voice channel information of the called access gateway to the calling access gateway, and transmits a ring tone to the calling subscriber; When the called party responds to the outgoing call, connecting the voice packet equipment of the asynchronous transmission mode network between the calling party and the called access gateway to access gateway subscriber line information using a media gateway control protocol. Way. 2. The media gateway control protocol of claim 1, wherein the source and destination access gateways provide a subscriber line name for the subscriber line as the access gateway internal station data so as to be distinguishable for each subscriber line connected thereto. Access gateway subscriber line information transmission method using. The channel of the dual tone multi-frequency signal equipment according to claim 1, wherein, when the call is originated by the calling party, the channel corresponding to the line number is controlled by the soft switch from the time the call is attempted to the subscriber line of the subscriber. A tone signal from a tone signal generating device for collecting a called number and generating a simultaneous tone signal by connecting a caller, and using the called party number and voice channel information of an originating access gateway as the identifier of the subscriber line line. Access gateway subscriber line information transmission method using a media gateway control protocol, characterized in that for transmitting to. 2. The apparatus of claim 1, wherein the calling party and the called party access gateway are real subscriber line and tone signal generators, dual tone multi-frequency signal generators, and asynchronous transmission mode voice packet transmission equipment for the subscriber under the control of the soft switch. Access gateway subscriber line information transmission method using a media gateway control protocol characterized in that for controlling the. The method of claim 1, wherein the source and destination access gateways, Receives events for hook-off, hook-on, hook flash, and digit of the subscriber from the subscriber line device unit as inter-process communication, exchanges messages with the MGCP stack processor using a common memory buffer unit, and provides an IP interface unit and an IP network. MGCP transmit / receive function with softswitch, and device (equipment) control unit controls time switch, dual tone multi-frequency signal generator and tone signal generator by library call to subscriber, time switch, dual tone multi-frequency A call controller for providing a DTMF signal and a tone signal, and connecting a voice channel and a time switch of a voice packet transmission device to perform a voice call between subscribers; A device control unit that manages resources related to the time switch, the DTMF signal generation unit, the tone signal generation unit, and the channel of the subscriber line, and performs a channel management function via the time switch under the control of a library call from the call control unit. Wow, An MGCP stack processing unit converting the message received from the call control unit into MGCP and transmitting the message to the soft switch via the IP packet processing unit, or by analyzing the MGCP received from the soft switch and converting the message to the message used by the call control unit; Media gateway control, characterized in that the MGCP received from the MGCP stack processing unit recombines the UDP (User Datagram Protocol) packet and converts it into an IP packet and the IP interface to perform an IP packet transmission and reception function in conjunction with the IP network Access gateway subscriber line information transmission method using a protocol. The method of claim 1, wherein the source and destination access gateways, And a unique identifier distinguishable in the asynchronous transmission mode network, and described in the session decryption protocol part of the media gateway control protocol message so that the access gateway can be referred to each time the access gateway is driven and the voice channel is connected. Access gateway subscriber line information transmission method using a media gateway control protocol. The method of claim 6, wherein the step of connecting the voice packet equipment of the asynchronous transmission mode network, Connecting the calling party and the called party access gateway to a fixed virtual circuit in the asynchronous transmission mode; The session description protocol part of the media gateway control protocol message is described as a unique call identifier of the voice transmission / reception channel information between the calling party and the called party subscriber using the virtual path identifier and the virtual channel identifier as the voice transmission / reception channel information between the gateway subscribers. Generating the call identifier value when allocating the asynchronous transmission mode voice channel resource using the unique identifier; And transmitting the call identifier value when the voice channel resource is released.