KR100279641B1 - Signal exchange apparatus and method - Google Patents

Abstract

The present invention relates to a signal exchange apparatus and method, and particularly, in an IP-based exchange system, by driving a call control scheme in a centralized and distributed manner to facilitate the installation of the system on an IP network and to call between groups (Call) It aims to prevent the possibility of sound quality deterioration due to the expansion of its own terminal in distributed call control system. The present invention for this purpose is registered in the lookup table 308 that stores the group number of each CO line number, the extension number for its own protocol interface, and the IP address for call translation / processing, and broadcasts and stores the registered information. When the call control process is finished, the task management unit 309 for switching the task to a voice call, and the distributed call control method to support the sharing of the trunk line within the group and the information sharing between the stations to perform the gateway function and the gateway function with the trunk line signal. By buffering the status information to its own terminal in voice communication, the call processing / agent 307 guaranteeing the quality of voice communication, and by matching the H.323 terminal with its own protocol to operate like its own terminal It supports intra-group communication and, conversely, by matching its own terminal to H.323 protocol to operate like H.323 terminal. Constitute a private multimedia system 210 that includes a conversion unit 306 on which the support remote VoIP communication by connecting to a network of trunk lines and LAN (LAN).

Description

Signal exchanger and method {SIGNAL EXCHANGE APPARATUS AND METHOD}

The present invention relates to a switching system, and more particularly, to a signal exchange apparatus and method in a private multimedia system.

Typically, offices are equipped with a private exchange or telephone system for phone calls and network equipment for data communication.

However, there are the following problems in the prior art.

1) LAN cables and telephone cables are conventionally wired independently, so that each communication line is double-wired to the user's desk by providing a private exchange or key phone system and data communication network equipment. There is a problem that takes time.

2) As the conventional private exchange method is unique to each company, it is difficult to frequently add capacity of the system, move offices, change information, etc. with the classic system setting and operation method, and also by independent operation of the voice and data system. There is a problem that the operation and management costs are doubled.

3) The conventional private switching system is a circuit switching scheme in which a unique communication channel called a time slot is allocated to voices of each trunk line and an extension station, and information between the channels is transferred to the other party through a memory buffer and exchanged. In addition to being limited by the capacity and speed of the switch, HDLC and other methods can be used to exchange signal information other than voice. There is a disadvantage that is very vulnerable to the figure.

In addition, in the related art, since the voice channel and the signal channel are dualized, the system has a complicated structure as well as a complicated software.

Therefore, the switching method of the conventional private switching system is very weak in scalability and is a voice-oriented switching system, which is structurally very difficult to interwork with multimedia communication over the data communication that is currently spreading to the Internet.

4) In the past, many companies own a leased line from a telecommunications company in order to reduce the cost of long distance and international calls between offices in each office, and pay a fixed monthly fee, and also use a remote network (WAN) between offices for internet access. There is a problem in that the cost increases because the head office pays the Internet connection fee at a fixed monthly fee by establishing a connection line to the ISP in the head office.

However, in the related art, since the call rate of a dedicated line for voice call is almost at rest except for the peak time, the monthly communication cost of the company can be reduced by routing voice communication to the WAN for the Internet.

Therefore, in recent years, the existing switching system of the circuit switching (Circuit Switching) method is replaced by the IP-based private switching system.

Such IP-based switching systems usually exchange based on the H.323 standard call control established by ITU-T as an international standard.

That is, the IP-based private switching system accepts and supports only terminals conforming to the H.323 protocol at the bottom.

The H.323 protocol is designed to support interoperability between different types of terminals with various voice and video codecs located on the Internet, aiming for product compatibility among companies internationally, and aims to communicate between terminals scattered locally. It takes 15 ~ 20 seconds to connect to a call and is suitable for point-to-point communication.

For example, the range of IP-based private exchanges (PBXs) in the office can provide the same functions as existing private exchange systems in the range of traffic management such as LAN and Internet. There is a need for a protocol for sharing the state of CO lines and terminals in a group such as a department, and for reducing traffic by simply multicasting such state information.

Currently, the IP-based switching system is applied like a conventional private switching system in a centralized call control method, so that all call requests are delivered to the system and the call is connected or terminated according to the terminal state in the system. An extension call can be made with only the terminal of the terminal. When the system is connected to the terminal, a trunk line call is possible.

Therefore, when the terminal and the switching system are implemented in a distributed call control method to process each call on their own, the installation of the product is easy and the failure conditions of the system can be distributed, thereby establishing a stable system.

At this time, the distributed call control method initially broadcasts its own information by broadcasting the identification name (ID) of the terminal or system to the IP network and transmitting it to the counterpart terminal or system in the broadcasting area. .

After that, if a change in status information (for example, Idle, etc.) related to all calls occurs, multicast the message in the form of a message and receive status information from the other party. And update them and simultaneously display them on a display device such as an LED or LCD provided on their terminal.

However, this distributed call control method has a disadvantage in that call quality is degraded in a single process because it must receive state information from various terminals or systems even during a call.

Therefore, it supports communication between groups of standard terminals or own terminals at the bottom of the system, and also supports remote Internet voice communication from any terminal, and maintains the advantages of an easy-to-install distributed call control method regardless of the expansion of terminals. There is a need for an IP-based private exchange system that provides voice.

Accordingly, the present invention facilitates the installation of the system on the IP network, provides a call function between groups and distributed call control scheme to drive the call control scheme in a centralized and distributed manner to improve the disadvantages of the conventional It is an object of the present invention to provide a signal exchange apparatus and method invented to block the possibility of sound quality degradation caused by the expansion of its own terminal.

That is, the present invention enables the communication between the H.323 terminal for compatibility in the lower part of the system or the internal terminal in the internal communication to easily share the status of the trunk line and the status information of the other terminal or make the call easily, Own terminal during voice communication This is to minimize the delay of the voice caused when performing tasks such as exchanging status information with various terminals of the counterpart.

The present invention for this purpose is implemented based on the non-real-time operating system (OS) of the PC (PC) because it implements a signal exchange method that can efficiently support QoS and functions based on the real-time operating system (OS) Compared to Call Server, call processing speed is faster and more reliable.

1 is a block diagram of a network for practicing the present invention.

2 is a block diagram of the private exchange system in FIG.

Figure 3 is an exemplary view showing the protocol structure of the call processing / agent of Figure 2;

4 is an exemplary view showing a registration process in FIG.

5 is a flowchart illustrating a call processing process in FIG.

6 is a block diagram of the call conversion circuit in FIG.

7 is an exemplary view illustrating a protocol structure of a voice processing unit in FIG. 2.

Explanation of symbols on the main parts of the drawings

210: private exchange system 220: router

230,240: Internet phone 250,260: Intranet phone

301: multi-channel trunk line connection unit 302: trunk line signal detection / generation unit

303: call signal detection / decision unit 304: H.323 gateway unit

305: H.323 gatekeeper 306: call conversion unit

307: call processing / agency 308: lookup table

309: task management unit 310: real-time operation (RTOS) unit

311: voice processing unit 312: network protocol unit

The present invention provides a network having a private multimedia system for connecting a trunk line and a LAN in order to achieve the above object, wherein the private multimedia system includes a group number of each trunk line number and an extension number for its own protocol interface. A lookup table that stores an IP address for call translation / processing, and registers call control information in the lookup table at the beginning of the system, broadcasts the registered information, and stores the task as a voice call when the call control process is finished. It supports the task management unit to switch and the shared call line sharing and inter-line information sharing in the group through distributed call control function to perform the telephone exchange function and the gateway function of the trunk line signal and buffer the status information to its own terminal in voice communication. Call processing / agent to ensure the quality of voice communication and H.323 terminals It supports intra-group communication by matching protocols and acting as its own terminal, and on the contrary, it includes a call conversion unit that supports remote Internet phone communication by matching its terminals with H.323 protocol and acting like H.323 terminal. It is characterized by the configuration.

When the call processing / agent receives a call agent message from a specific terminal at the start of a call, the call processing / agent receives all call control messages from the corresponding terminal, updates the contents of the lookup table, and processes the call control message of the corresponding terminal delegated during the call. And when the call connection release message is received from the terminal, the final change information is sent to the terminal to update the lookup table of the terminal itself.

The call conversion unit includes a plurality of protocol interface blocks for matching protocols between a plurality of H.323 terminals and a plurality of own terminals, and the plurality of protocol interface blocks support H.323 protocol interfaces. And a protocol matching circuit for each of the interface circuits, and a protocol matching circuit for 1: 1 correspondence of the respective interface circuits.

Each of the plurality of protocol interface blocks has one independent IP address.

In addition, the task management unit stores the group number of each CO line number from the user, the extension number for its own protocol interface, and the IP address for call translation / processing in the lookup table in order to achieve the above object. And a process of storing and broadcasting information of an extension number, IP address, and affiliation group number from a user in a terminal, and a system or its own terminal that has received the broadcasted information. Process of unicasting the call to the calling party and a change in communication status Multicasting a call status message from a terminal to another terminal or system, receiving the multicasted message to update the calling party status information, and determining whether a call substitute message is received from any terminal to initiate a call And receiving all call control messages from the delegated terminal, updating the contents of the lookup table, detecting the state of the terminal in a call, and finally changing the terminal to the terminal after the call. And transmitting the information to update the contents of the lookup table of the terminal itself.

The terminal itself is characterized in that it comprises a h.323 terminal that is self-terminal.

Hereinafter, the present invention will be described in detail with reference to the drawings.

As shown in the configuration diagram of Fig. 1, the network for carrying out the present invention stores and calls an IP address and various state information while performing both protocol conversions to connect a public telephone network and a LAN (270). A private multimedia system 210 that handles call control or other additional functions, and a Windows NT-based system application function that is connected to the private multimedia system 210 to perform data transmission / reception with a private network / Internet network. Internet phone 230 and 240 and intranet phone 250 and 260 connected to a router 220 and a LAN 270 and provided with its own protocol to perform voice communication. It is equipped with.

As shown in the block diagram of FIG. 2, the private multimedia system 210 converts the H.323 terminal into its own protocol, assigns the same group to share a specific trunk line with its own terminal, and uses voice in call control. Task to transfer tasks to currency Registration of the management unit 309, the H.323 gateway unit 304 that converts the trunk line signal into the H.323 signal and the H.323 signal into the trunk line signal, and the H.323 terminal that supports the H.323 communication protocol. H.323 gatekeeper (305) of 'Direct Endpoint Call Signaling' method that connects IP address translation and two-way connection, and distributed call control protocol in LAN or Internet. It includes the telephone exchange function like the existing private switching system and the gateway function with the CO line signal, and it guarantees the quality of voice communication by buffering the status information of other terminals and gateways to the terminal in voice communication. By processing between the processing / agent 307 and its own protocol and the H.323 protocol, the H.323 terminal is self-supported to support intra-group communication and its own terminal is H.323. Call conversion unit 306 supporting the remote Internet phone communication function, and detects the incoming call signal through the CO line, according to the pre-programmed content in the task management unit 309 according to the CO line number H.323 gateway unit ( 304) or the call processing / agent 307, and detects a call control message from the H.323 terminal or its own terminal at the bottom of the system to the H.323 gatekeeper 305 or the call processing / agent 307. The call signal detection / determination unit 303 and the multi-channel trunk line connection unit 301 are connected to various trunk lines to detect ring signals and DTMF signals, and transmit the ring signals and DTMF signals to the call signal detection / determination unit 303. CO line signal detection / generation unit for generating the corresponding DTMF signal according to the signal message from .323 gateway unit 304 or call processing / agent 307 and transmitting to multiple trunk lines through multi-channel trunk line connection unit 301 ( 302), and the audio flow of the H.323 standard Uniform and is performed on a separate real-time operating (RTOS) 310 A voice processing unit 311 for processing high quality voice, a network protocol unit 312 for transmitting call-related messages in connection with a LAN, and a real-time operation (RTOS) unit 310 for operating a control program in real-time multitasking. ).

As shown in the block diagram of FIG. 6, the call conversion unit 306 includes a plurality of protocol interface blocks 640-1 to 640-N for matching protocols between a plurality of H.323 terminals and a plurality of own terminals. And the protocol interface blocks 640-1 to 640 -N include an H.323 protocol interface circuit 610 for supporting an H.323 terminal, and a protocol protocol circuit 630 for supporting its own terminal. And protocol matching circuits 620 that each correspond to the interface circuits 1: 1.

The protocol interface blocks 610-1 to 610-N each have one independent IP address.

Referring to the operation and effect of the embodiment of the present invention configured as described above are as follows.

In general, a call control message and a registration message are required for a call in an IP-based system.

In general, call control to set up or release a call is divided into 'Call Setup', 'Call Accept', 'Call Connection', and 'Call Disconnection'. 'Call Status' for sharing communication status information (Idle during call) between own terminals is included.

Call control information for call establishment and connection release is transmitted in the form of a message through an IP network.

Then, the registration message is information for exchanging information of the belonging group information and the extension number or the trunk line number and the IP address in the initial stage of the own terminal or system.

In an embodiment of the present invention, the private multimedia system 210 as shown in the block diagram of FIG. 2 transmits the call control message and the registration message through the UDP / IP of the network protocol unit 312.

This is because it is efficient to share communication state information in a group by using the characteristics of UDP broadcasting and multicasting, and there is no problem in communication from the LAN to the UDP.

In the present invention, the own terminal and the call processing / agent 307 are operated as a registration process and a call control process.

The registration process is performed in the same manner as the signal flow of FIG. Here, in Fig. 4, the solid line (→) indicates the path of the registration message, and the dotted line (...) indicates the path of the response message.

First, the private multimedia system 210 includes a group number of each CO line number from the user, an IP address of the call processing / agent 307, an extension number of its own protocol interface circuit 630 of the call conversion unit 306, and The task manager 309 stores the IP address in the lookup table 308 and immediately broadcasts it in the form of a registration message.

Here, the call processing / agent 307 has a protocol having the structure as shown in FIG.

In addition, the own terminals 401 and 402 such as the intranet 250 and 260 in FIG. 1 receive the information of the extension number, the IP address, and the belonging group number from the user, and store the information in the internal lookup table. Broadcast immediately in the form of a registration message.

At this time, the own protocol interface circuit 630 of the own terminal 403 or 404 or the call processing / agent 307 or the call converting unit 306 that has received the registration message unicasts its registration information to the calling party in the form of a response message. (Unicast)

Thereafter, when there is a change in communication status information for an extension call or a trunk line call with a terminal (including H.323 terminalized 401) 402 of its own terminal (403) (404) in the same group. The call status message is multicasted to the call conversion unit 306 and the call processing / agent 307 of all the terminals or the private multimedia system 210 in the same group.

Here, the H.323 terminals 401 and 402 are terminalized by the call conversion unit 306.

Accordingly, the terminal or private multimedia system 210 receiving the call status message updates the calling party status information in the lookup table.

In particular, the terminal notifies the user by displaying the calling party status on a display device such as an LED or an LCD.

In the above, the call conversion unit 306 supports intra-group communication by matching the H.323 terminals 403 and 404 with its own protocol and acting as its own terminal, and conversely by matching the own terminals 401 and 402 with the H.323 protocol. To act like an H.323 terminal By supporting remote Internet phone communication, as shown in the block diagram of FIG. 6, a plurality of protocol interface blocks 640 for matching a protocol between a plurality of H.323 terminals and a plurality of own terminals in a 1: 1 correspondence. -1 to 640-N) to have one independent IP address.

At this time, each of the interface blocks 610-1 to 610 -N is registered by the task manager 309 at the power-on time by each protocol procedure.

That is, the H.323 protocol interface circuit 610 provided in each of the protocol interface blocks 640-1 to 640 -N registers information such as an IP address to the H.323 gatekeeper 305 by the H.323 protocol. The own protocol interface circuit 630 broadcasts its own extension number, IP address, trunk line number, etc. to the IP network based on its own registration procedure.

And, when the H.323 terminal 401 (402) and the H.323 protocol interface circuit 610 performs a protocol process, the exchange of capability information (audio codec information) is used to communicate information of its own terminal (403 or 404) to communicate. Use it as it is.

However, in the distributed system as described above, the burden of processing the call control message increases as the number of terminals increases.

In other words, if the terminal is not in a call, there is no problem because there is no strict voice control burden in real time, but in the case of a low-cost terminal which simultaneously processes voice and call control messages in the same processor, it may cause a drop in sound or a transmission delay. .

Therefore, in order to solve this problem, in the present invention, the terminal is initiated when the call is initiated. A new call control message called a call proxy message is generated and transmitted to the call processing / agent 307 provided in the private multimedia system 210.

Thereafter, the call processing / agent unit 307 receives all call control messages to the delegated terminal and updates the contents of the lookup table 308.

At this time, the terminals 401 to 404 that terminated the call transmit a 'Call Disconnect' message to the call processing / agent 307.

Accordingly, the call processing / agent 307 immediately sends the last change information in the updated lookup table 308 to the corresponding terminal among the terminals 401 to 404, and the corresponding terminal receiving the information message receives its own lookup table. And display it on a display such as an LED or LCD.

Call processing in the above process is the same as the signal flow of FIG. Here, in Fig. 5, the solid line (→) indicates a multicast, the dashed-dotted line indicates a broadcast, and the dashed line indicates a unicast.

On the other hand, in the present invention will be described the call process between the terminal and the trunk line as follows.

First, when one of the terminals under the LAN 270 is off-hook for a call from the own terminal to the trunk line, the status information 'BUSY' is transmitted to the private multimedia system 210 in the form of a packet message. Be notified.

At this time, the network protocol unit 312 connected to the LAN 270 transmits a call related packet message to the call signal detection / decision unit 303 and the call signal detection / decision unit 303 is associated with the call. The packet message is transmitted to the H.323 gatekeeper 305 or the call processing / agent 307.

Accordingly, the call processing / agent 307 updates the corresponding terminal state information of the lookup table 409 and notifies the call conversion unit 306 to ensure the quality of voice communication.

In this case, the call conversion unit 306 converts its own protocol into an H.323 terminal and converts its own terminal into an H.323 terminal to support a remote Internet phone communication function. The protocol interface blocks 640-1 to 640- The H.323 signal is transmitted to the H.323 gateway unit 304 through its own protocol interface circuit 630, the protocol matching circuit 620, and the H.323 protocol interface circuit 610 provided in one block of N). do.

Accordingly, the H.323 gatekeeper 305 controls the H.323 gateway unit 304 to associate the registration IP address translation of the H.323 terminal supporting the H.323 communication protocol and the connection between the two parties. The H.323 gateway unit 304 converts the H.323 signal into a trunk line signal.

Accordingly, the trunk line signal detection / generation unit 302 generates the corresponding DTMF signal according to the signal message from the H.323 gateway unit 304 or the call processing / agent unit 307 through the multi-channel trunk line connection unit 301. Transmit to the CO line.

On the contrary, when a ring signal and DTMF signal are input through the multi-channel trunk line connection unit 301 for a call from the trunk line to its own terminal, the trunk line signal detection / generation unit 302 detects the input signal and calls the call signal detection / determination unit. Send to 303.

At this time, the call signal detecting / determining unit 303 recognizes the trunk line number upon detecting the call signal and according to the contents pre-programmed in the task manager 309, the H.323 gateway unit 304 or the call processing / agent unit 307. To send).

Accordingly, the H.323 gateway unit 304 converts the C.O.line signal from the call signal detection / determination unit 303 into an H.323 signal under the control of the H.323 gatekeeper 305, thereby generating its own protocol and H.323. 323 is transmitted to the call processing / agent 307 through the call conversion unit 306 which performs conversion between protocols.

At this time, the call processing / agent 307 updates the corresponding state information of the lookup table 308 and transmits the packet message to the terminal under the LAN 270 through the network protocol unit 312.

Therefore, when the other party responds in the above-described process, the caller can talk to each other through the call path in which the ringback tone is transmitted. In the call, the voice signal from the trunk line is transmitted through the multi-channel trunk line connection unit 301. The voice packet from the LAN 270 is transmitted to the voice processor 311 via the network protocol unit 312.

At this time, the voice processing unit 311 having a protocol as shown in FIG. 7 converts a voice signal into a voice packet and converts the voice packet into a voice signal in real time under the control of a real-time operation (RTOS) unit 310. Will be sent to both sides.

Therefore, a call is made between the telephone on the trunk line and the terminal under the LAN.

After that, when the call is placed on the hook to terminate the call processing / agent 30 updates the corresponding state information of the lookup table 308 to idle and multicasts it into the group to register.

As described in detail above, the present invention can exert the following effects, thereby replacing the conventional private voice exchange system and the current IP-based private exchange system. can do.

1. The present invention accepts a H.323-based standard terminal to provide communication with a remote standard terminal.

2. The present invention performs the intra-group communication function by making the standard terminal itself

It is possible to perform efficient communication because it can perform remote internet phone communication function by making its own terminal into a standard terminal.

3. The present invention can provide a voice communication function of a certain quality regardless of the expansion of the terminal by combining efficient distributed call control and centralized call control in intra-group communication.

4. The present invention can implement high quality voice communication by independent of the real time operation (RTOS) and the processor for voice processing.

Claims (7)

In a network having a private multimedia system for connecting a trunk line and a LAN, the private multimedia system includes a group number of each trunk line number, an extension number for its own protocol interface, and an IP address for call translation / processing. A look-up table to store, a task manager that registers call control information in the look-up table at the beginning of the system, broadcasts and stores the registered information, and switches the task to a voice call when the call control process is finished; It supports sharing of CO lines within a group and sharing information between stations, and performs call exchange function and gateway function with CO line signal, and buffers status information to its own terminal during voice communication to guarantee the quality of voice communication. / Agent matches H.323 terminal with its own protocol and acts like its own It supports intra-group communication by vice versa, and conversely, it includes a call conversion unit that supports remote Internet phone communication by matching its own terminal to H.323 protocol and acting like H.323 terminal. Device. According to claim 1, When the call processing / agent receives a call agent message from a specific terminal at the start of the call receives all call control messages from the terminal to update the contents of the lookup table and call control messages of the terminal delegated during the call After receiving the call disconnection message from the terminal, it updates the lookup table of the terminal itself. And transmit the last change information to be reliable. The apparatus of claim 1, wherein the call conversion unit comprises a plurality of protocol interface blocks for matching the protocols of the plurality of H.323 terminals and the plurality of own terminals in a 1: 1 correspondence. 4. The method of claim 3, wherein the plurality of protocol interface blocks comprises an H.323 protocol interface circuit for supporting an H.323 terminal, an own protocol interface circuit for supporting its own terminal, and one-to-one correspondence of the respective interface circuits. A signal exchange device comprising a protocol matching circuit. The signal exchange apparatus according to claim 3 or 4, wherein the plurality of protocol interface blocks are configured to have one independent IP address. A call information registration method of a network having a private multimedia system for connecting a trunk line with a LAN, comprising: a group number of each trunk line number from a user at the beginning of the system, an extension number for its own protocol interface, and call conversion / A first process of storing and broadcasting an IP address for processing in a look-up table by a task manager; a second process of storing and broadcasting information of an extension number, an IP address, and a belonging group number from a user in a terminal; When broadcasts received from A third process of the system or the own terminal unicasting its registration information to the calling party, and a process of multicasting the call status message from the own terminal to the other terminal or system where a change in communication status has occurred for an extension call or a trunk line call. Step 4, a fifth step of receiving the multicasted message and updating the calling party status information, a sixth step of determining whether a call proxy message is received from any terminal to initiate a call, and the call proxy message. Is received, receives all call control messages from the delegated terminal, updates the contents of the lookup table, detects the state of the terminal in a call, and sends the final change information to the terminal after the call is terminated. Signal exchange, characterized in that to perform a seventh process of updating the content Law. 7. The method of claim 6, wherein the self terminal comprises an H.323 terminal which is self terminalized.