KR100405596B1 - VoIP Gateway System - Google Patents

Abstract

The present invention relates to a VoIP gateway system for providing Voice over Internet Protocol (VoIP) to an existing ISDN subscriber using an ISDN interface in an integrated service digital network (ISDN) service network.

The present invention provides a voice service or a data service by using an IP network by matching an existing ISDN using an ISDN interface in an ISDN service network, and providing VoIP to an existing ISDN subscriber, without changing TE or NT. Voice and data services are provided simultaneously through a single interface to existing ISDN subscribers, and the VoIP technology allows users to use voice call services without a physical connection between end-to-end through the implementation of VoIP technology. Not only can you save money, but you also save money on the purchase of new equipment.

Description

VIP Gateway System {VoIP Gateway System}

The present invention relates to a VoIP gateway system, and more particularly, to a VoIP gateway system for providing VoIP to an existing ISDN subscriber using an ISDN interface in an ISDN service network.

1 is a block diagram showing a network configuration for a conventional ISDN service, comprising two TEs (11, 12), a TA (13), an NT (14), and an ISDN (15). Reference numeral 14 denotes a network termination and includes two terminations 14-1 and 14-2.

As shown in FIG. 1, a classification according to each functional group and a reference point for distinguishing an interface between installation elements are configured. TE (11), the second TE (12), TA (13), the first NT (14-1) and the second NT (14-2), the reference point is a second TE (12) and TA R point between (23), S point (S) between the first TE (11) and the second NT (14-2), and between the TA (13) and the second NT (14-2), and It consists of a tie point T between one NT 14-1 and a second NT 14-2 and a unique point U between the first NT 14-1 and ISDN 15.

In addition, the above-described network configuration for the ISDN service is according to the respective functions of the first TE (11), the second TE (12), the TA (13), the first NT (14-1) and the second NT (14-). 2) and further includes a central office (CO) in the ISDN 15 (not shown in the drawings for convenience of description).

The first TE 11, the second TE 12, and the TA 13 are devices for configuring a subscriber terminal. The first TE 11 is an ISDN terminal capable of interworking with an ISDN S interface. The second TE 12 refers to a non-ISDN terminal, such as a host computer or a general public switched telephone network (PSTN) phone, which is a non-ISDN terminal. In the ISDN is converted to the S interface by the corresponding equipment (13), which is available to use as an ISDN terminal.

The NT 14 refers to the physical and electronic termination of the ISDN 15. The NT 14 converts data applied from the ISDN terminal or the second NT 14-2 into a U interface to provide interworking with the ISDN CO. To provide the actual ISDN service.

In addition, the NT 14 may be subdivided into the first NT 14-1 and the second NT 14-2, and the first NT 14-1 may have a corresponding ISDN in the NT 14. 15), and the second NT 14-2 is a system such as a digital private branch exchange (PBX), which is connected to a tie interface for connection with the first NT 14-1. It performs the function of the S interface for accessing the first TE 11 and the TA 13.

The data flow of the voice service in the network configuration for the above-described ISDN service will be described briefly as follows.

The data of the non-ISDN subscribers is transmitted to the TA 13 through the second TE 12, which is a non-ISDN terminal, and converts the data from the TA 13 to the S interface to the NT 14. Do it.

Data of ISDN subscribers is directly applied to the NT 14 through the first TE 11, which is an ISDN terminal.

Accordingly, the NT 14 receives data from the TA 13 or the first TE 11 and performs a multiplexing function of byte interleaving, that is, byte interleaving. To the CO of the ISDN (15).

However, the ISDN service in the network for the conventional ISDN service configured as described above is an ISDN-based communication service, and the voice service is capable of end-to-end connection through many ISDN exchanges. As a service, a long distance voice service has a problem in that a subscriber has to pay a lot of costs according to distance when using such a voice service by using many ISDN exchanges.

In order to solve the above problems, the present invention implements a VoIP gateway system using an ISDN interface in the ISDN service network, to provide voice services or data services in the existing ISDN using an IP network, There is a purpose.

In addition, the present invention provides VoIP to subscribers using existing ISDN using ISDN PBX or ISDN terminal in ISDN service network, so that voice and data, which is the biggest advantage of ISDN, are not changed without TE or NT. The service provided at the same time through the interface of the existing ISDN subscribers, and through the implementation of the VoIP technology to enable the voice call service without a physical connection between end-to-end, it is possible to reduce the voice service fee It also aims to reduce the cost of purchasing new equipment.

1 is a block diagram showing a network configuration for a conventional integrated service digital network (ISDN) service (Service).

2 is a block diagram showing the configuration of an ISDN service network according to an embodiment of the present invention.

FIG. 3 is a block diagram illustrating an ISDN Voice over Internet Protocol (VoIP) Gateway in FIG. 2; FIG.

FIG. 4 is a diagram illustrating an integrated network using the ISDN VoIP gateway in FIG. 2; FIG.

Explanation of symbols on the main parts of the drawings

21, 22: TE (Terminal Equipment) 23: TA (Terminal Adapter)

24: NT (Network Termination) 25: ISDN VoIP Gateway

26: IP (Internet Protocol) network

31: ISDN Subscriber Access Controller (SAC)

32: D-channel handler

33: Pulse Code Modulation Interface Controller (PCMIC)

34: DSP (Digital Signal Processor)

35: RAM (Random access Memory) 36: Memory

37: EC (Ethernet Controller) 38: Main Processor

VoIP gateway system according to an embodiment of the present invention for achieving the above object is an ISDN SAC (Subscriber Access Controller) for providing a subscriber interface by performing an integrated service digital network (ISDN) interface; A de-channel handler which handles de-channel data among signals applied from subscribers through the ISDN SAC so as to be used for non-channel control or for transmitting small capacity data; Extract the voice data applied from the subscriber by the non-channel into PCM data, and transmit PCM (Pulse Code Modulation) data applied through each port to the PCM highway channel allocated by the time division multiplexing (TDM) switch. A Pulse Code Modulation Interface Controller (PCMIC) for switching; Compressed data is transmitted to an IP network by IP (Internet Protocol) packetization, and includes an EC (Ethernet Controller) for restoring an IP packet received from the IP network.

Preferably, the ISDN SAC performs an interface between the ISDN S reference point and the ISDN T reference point to match with the ISDN terminal through the S interface (S-Interface), and to match with the TA (Terminal Adapter) through the S interface and the tie interface. It is characterized by matching with NT (Network Termination) through (T-Interface).

Alternatively, the VoIP gateway system according to an embodiment of the present invention compresses PCM data applied from the PCMIC to transmit the compressed data to the EC, and restores compressed data applied from the EC to the PCMIC. A digital signal processor (DSP); It further comprises a main processor for controlling and managing the operation of each of the building blocks, and performs the protocols and functions for providing a service.

Preferably, the main processor implements protocols related to call processing for establishing and releasing a call in case of providing Voice over Internet Protocol (VoIP), and provides a protocol and a function for processing real-time data in case of voice communication. It is characterized by the implementation.

The present invention implements a VoIP gateway system using an ISDN interface, and enables the corresponding VoIP gateway system to be interoperable without replacing an existing ISDN terminal or NT. In addition, the present invention implements a VoIP gateway system for providing an existing ISDN service over an IP network, and the VoIP gateway system transmits ISDN data to the IP network using compression of a DSP. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2, the ISDN service network according to an embodiment of the present invention includes two TEs 21 and 22, a TA 23, an NT 24, an ISDN VoIP gateway 25, and an IP. Network 26, where reference points include an R point between the second TE 22 and the TA 23, between the first TE 21 and the ISDN VoIP gateway 25, and the TA ( 23) and an es-point S between the ISDN VoIP gateway 25 and a tie point T between the NT 24 and the ISDN VoIP gateway 25. FIG.

Here, the first TE 21, the second TE 22, and the TA 23 are devices for configuring a subscriber terminal, and the first TE 21 is an ISDN terminal, and the second TE ( 22) is a non-ISDN terminal, the corresponding TA 23 is a separate equipment to enable the use of the second TE 22 as an ISDN terminal. In addition, the NT 24 is a physical and electronic end point of the ISDN, and is a terminal that provides interworking with the ISDN CO through the u interface to receive the actual ISDN service. In addition, the ISDN VoIP gateway 25 interworks with the corresponding first TE 21, the TA 23, and the NT 24 using the ISDN interface, that is, the corresponding first TE 21 and the TA through the S interface. By interworking with (23) and interworking with the corresponding NT (24) through the tie interface, it provides the actual ISDN service provided through the corresponding NT (24) through the corresponding IP network (26).

As shown in FIG. 3, the ISDN VoIP gateway 25 includes an ISDN SAC 31, a de-channel handler 32, a PCMIC 33, a DSP 34, and a RAM 35. And a memory 36, an EC 37, and a main processor 38.

The ISDN SAC 31 is a block for performing an ISDN interface. The ISDN SAC 31 performs an interface between an ISDN S reference point and an ISDN T reference point, that is, matches with the first TE 21 through an S interface and through an S interface. It matches with the TA 23 and through the tie interface with the NT 24 to provide a subscriber interface.

The de-channel handler 32 handles the de-channel data which is a control signal channel of the ISDN among the signals applied from the subscriber through the ISDN SAC 31 under the control of the main processor 38. Do this.

The PCMIC 33 converts the voice data applied from the subscriber to the PCM data through the ISDN SAC 31 under the control of the main processor 38 and converts the PCM data applied through the respective ports. Performs the function of switching to the PCM Highway Channel assigned by the TDM switch.

The DSP 34 is a block for performing voice signal processing such as voice compression, and performs voice PCM signal processing such as compression on PCM data applied from the PCMIC 33 under the control of the main processor 38. The data is applied to the EC 37, and the data applied from the EC 37 is applied to the PCMIC 33 by performing voice PCM signal processing such as restoration.

The RAM 35 stores a program and various data necessary for performing the operation of the DSP 34.

The memory 36 stores a program and various data necessary for performing the operation of the main processor 38.

The EC 37 is a block for transmitting and receiving data with the IP network 26 and performs a packet conversion function for IP packetizing data applied from the DSP 34 under the control of the main processor 38. The IP packetized packet is transmitted to the IP network 26, and the IP packetized packet received from the IP network 26 is converted into original data and applied to the DSP 34.

The main processor 38 is a block for performing system control and management, conversion into RTP packets, and services provided. The main processor 38 performs control and management functions for each functional block, and converts into RTP packets. And a protocol for providing a service such as call processing.

As described above, the present invention uses the existing equipment such as TE (21, 22), TA (23), or NT (24), which is used in the existing ISDN, the connection of the ISDN through the existing wire interface Ethernet interface By connecting to the IP network 26 via the IP network 26, the service in the existing ISDN is implemented on the IP network 26, which is a data network, rather than through the ISDN.

Referring to the data flow of the voice service in the ISDN service network according to an embodiment of the present invention.

As shown in FIG. 2, the ISDN VoIP gateway 25 performs a tie interface for interworking with the NT 24 that matches the ISDN CO as a physical and electronic end of the ISDN, and performs a first TE 21 as an ISDN terminal. And S interface for interworking with the TA 23 matching the non-ISDN terminal and interworking with the IP network 26 to provide the existing ISDN service through the corresponding IP network 26. That is, the ISDN data is transmitted to the corresponding IP network 26.

3, each component block of the ISDN VoIP gateway 25 performs the following operation.

First, the ISDN SAC 31 performs matching with the first TE 21 through an S interface, performs matching with the TA 23 through an S interface, and matches the NT 24 through a tie interface. By performing matching, the connection interface of the existing ISDN subscribers is provided, and the de-channel data, which is the control signal channel of the ISDN, is applied to the de-channel handler 32 among the signals authorized from the ISDN subscribers, and the ISDN The voice data is applied to the PCMIC 33 among the signals applied from the subscribers.

Accordingly, the de-channel handler 32 handles the de-channel data applied from the subscriber through the ISDN SAC 31 and informs the main processor 38.

The PCMIC 33 converts the voice data applied from the ISDN subscriber to the PCM data through the ISDN SAC 31 and transfers the PCM data applied through the respective ports to the PCM highway channel assigned by the TDM switch. Switch.

Accordingly, the DSP 34 applies the PCM data applied from the PCMIC 33 to the EC 37 by performing voice PCM signal processing such as compression, and conversely, the data applied from the corresponding EC 37 is applied. Voice PCM signal processing such as restoration is performed and applied to the PCMIC 33.

Then, the EC 37 performs a packet conversion function for IP packetizing the data applied from the DSP 34 under the control of the main processor 38 to perform the IP packetization on the IP packetized packet. On the contrary, the IP packetized packet received from the IP network 26 is converted into original data and applied to the DSP 34.

In addition, the main processor 38 and the memory blocks 35 and 36 perform control and management functions on the respective building blocks, and functions such as priority control, scheduling, etc. for each of the performing processors are performed. Provides and implements and executes protocols to provide services to implement.

For example, in the case of a system providing VoIP, protocols related to call processing for call establishment and release are implemented. As another example, in the case of voice communication, since data is real-time data, a protocol and a function for processing real-time data are implemented.

The substantial data flow according to the functions of the respective building blocks described above is as follows.

In the case of the data flow of the VoIP service using the first TE 21, the TA 23, or the NT 24, the de-channel data applied from the terminal is extracted by the de-channel handler 32. De-channel data is used for B-channel control or for small data transmission.

The voice data applied from the terminal is extracted from the PCMIC 33 by the non-channel and converted into PCM data. The PCM data is switched to the PCM highway channel assigned by the TDM switch.

Accordingly, the PCM data is compressed using a compression technique, which is a great advantage of the data network, in the DSP 34, rather than directly converting the PCM data into an IP packet and then transmitting the compressed data to the EC 37. Authorize by.

Accordingly, the EC 37 performs a packet conversion function for IP packetizing the data compressed by the DSP 34 to transmit the IP packetized packet to the IP network 26.

At this time, of course, all voice packets are processed in real time in order to maintain real-time characteristics that are characteristic of voice data, and call setup and release in the IP network 26 are also performed under the control of the main processor 38.

The reverse operation is similar to that described above, and thus description thereof is omitted.

On the other hand, when configuring the integrated network using the ISDN VoIP gateway in the ISDN service network according to an embodiment of the present invention as shown in Figure 4, the ISDN VoIP gateway 25 is a direct IP network 26 through the EC (27) It is shown that it matches with an ISDN terminal such as a host computer or a general PSTN telephone corresponding to the first TE 21 through the S interface.

As described above, although the implementation of the ISDN VoIP gateway system using the ISDN terminal is described, many additional services provided by ISDN as well as VoIP service, namely, simultaneous call function, data transmission through the de-channel Also, it should be understood that the facsimile processing function can be provided and implemented in the upper layer.

As described above, the present invention provides a voice service or a data service by using an IP network by matching an existing ISDN using an ISDN interface in an ISDN service network, and providing VoIP to an existing ISDN subscriber, without changing TE or NT. It provides the ISDN subscriber with the service that provides voice and data simultaneously through one interface, which is the biggest advantage of the network, and enables the voice call service without the physical connection between end-to-end by implementing the VoIP technology. This can reduce the cost of using voice services, as well as the cost of purchasing new equipment.

Claims (4)

An ISDN Subscriber Access Controller (SAC) that provides an access interface for subscribers by performing an Integrated Service Digital Network (ISDN) interface; A de-channel handler which handles de-channel data among signals applied from subscribers through the ISDN SAC so as to be used for non-channel control or for transmitting small capacity data; Extract the voice data applied from the subscriber by the non-channel into PCM data, and transmit PCM (Pulse Code Modulation) data applied through each port to the PCM highway channel assigned by the time division multiplexing (TDM) switch. A Pulse Code Modulation Interface Controller (PCMIC) for switching; The BIP gateway system comprising an EC (Ethernet Controller) for converting compressed data into IP (Internet Protocol) packets and transmitting them to an IP network and restoring an IP packet received from the IP network. The method of claim 1, The ISDN SAC performs an interface between an ISDN S reference point and an ISDN T reference point to match with an ISDN terminal through an S-Interface, and to match a TA (Terminal Adapter) through an S interface, and a T-Interface. V) IP gateway system, characterized in that it matches with Network Termination (NT). The method of claim 1, A digital signal processor (DSP) for compressing the PCM data applied from the PCMIC to transmit the compressed data to the EC, and restoring the compressed data applied from the EC to the PCMIC; The VIP gateway system of claim 1, further comprising a main processor that controls and manages operations of the building blocks and performs protocols and functions for providing a service. The method of claim 3, The main processor implements protocols related to call processing for call establishment and release when providing Voice over Internet Protocol (VoIP), and implements protocols and functions for processing real-time data in case of voice communication. VIO IP gateway system.