JP2002044155A - Individual line termination method and system in virtual switching function on ip network - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a system that unify resource management at a virtual switching function level independently of a signal system by integrating a termination processing function of an individual line signal to a signal gateway in the virtual switching function realized by cooperation of a group of gateways distributed on an IP network. SOLUTION: A media gateway adopts an NNI(network Node Interface) employing an individual line signal system for an interface with a switching node, receives an individual line control signal extracted from an NNI individual line, assembles the signal into packets, transfers a signaling gateway arranged on an IP network and conducting common line signal termination and the signaling gateway terminates the individual line signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and system for terminating an individual line in a virtual switching function in an IP network.

[0002]

2. Description of the Related Art IP (Internet Protocol)
ol) A virtual switching function realized by the cooperation of a group of gateway devices distributed in a network is a medium that performs a trunk interface with a switching node and relays connection of a trunk to various servers or IP subscribers existing on an IP network. This is realized by the cooperation of the gateway device and the signal gateway device performing the common channel signal termination function.

[0003] In VoIP (Voice over IP) transmitting voice, for example, via an IP network, a gateway device connected to a telephone exchange uses ITU-T.
(International Telecommunication Union Telecommunication Standardization Sector) 3
No. 23 No. 2 and the like. H.248 (gateway control protocol), H.323 gateway function is provided by a media gateway (Media G).
ateway), signaling gateway (Sign
aling Gateway), Media Gateway Control
It adopts a distributed architecture divided into two.

[0004] Among the gateway devices distributed in the IP network, a media gateway is connected to a public telephone network via a telephone line, and transmits voice, images, and computer data in packets. The signaling gateway is a control signal system between exchanges defined by ITU-T, SS7 (Signaling System N).
o. 7), etc., a function of transmitting various signals within the IP packet network. Media gateway control (MGC)
Receives a signal from a signaling gateway, performs address resolution and bandwidth management, selects an appropriate media gateway device, and provides a service. Media gateway control (MGC) is a billing server in the IP network,
The media gateway is connected to the management server, and the media gateway is connected to the authentication server or the like.

[0005]

However, in the conventional system, there is no configuration that supports the individual channel signaling system.

One of the reasons is that, in the common channel signaling system, a control signal line is provided as an independent interface separately from a communication line. Therefore, the signaling gateway device pulls in the control line to control the control signal line. However, in the case of the dedicated channel signaling method, since the control signal is added to the communication line, an interface with the signaling gateway device cannot be obtained.

Accordingly, the present invention has been made in view of the above problems, and a main object thereof is to provide an individual line signal in a virtual switching function realized by cooperation of a group of gateway devices distributed in an IP network. It is an object of the present invention to provide a method and a system in which the termination processing function can be integrated into a signal gateway device, and resource management at a virtual switching function level is unified irrespective of a signaling system.

It is another object of the present invention to provide a method and system for reducing the cost of a media gateway device by consolidating an individual line signal termination function in a signal gateway device.

[0009]

SUMMARY OF THE INVENTION The present invention, which achieves the above object, is arranged in an IP (Internet Protocol) network, and performs a trunk interface with a switching node to form a trunk with a server or an IP subscriber existing on the IP network. A media gateway device that performs connection relaying uses an individual line signaling method for an interface with a switching node.
NI (Network Node Interface)
Receiving an individual line control signal extracted from the NNI individual line,
The data is transferred to a signaling gateway device arranged in the IP network, and terminated at the signaling gateway device.

[0010] Individual line control signals of a plurality of media gateway devices distributed in the IP network are collectively terminated by a signaling gateway disposed in the IP network.

[0011] The present invention is installed in a plurality of IP networks,
An NNI (Network Node Interface) using a dedicated line signaling system is accommodated in the interface with the switching node, and trunk relaying, and the out-of-band signal and the in-voice signal of the dedicated line signal are transmitted via the IP network. A media gateway device for transferring to the signaling gateway device, and a signaling gateway device installed on the IP network for terminating a dedicated line signal transferred from the media gateway device and establishing a signal sequence with the switching node; Is provided.

[0012]

Embodiments of the present invention will be described. As mentioned above, IP (Interne Pro
The virtual switching function realized by the cooperation of a group of gateway devices distributed in a tocol network is a media gateway (trunk interface between switching nodes and a media gateway (trunk connection relaying trunk connection with various servers or IP subscribers existing on the IP network). Media Gateway; "MG
W) and a signaling gateway (SignalingG) that performs a common channel signal termination function.
ateway (also abbreviated as “SWG”).

The present invention provides an NNI (Network Nod) using an individual line signaling system which has not been realized until now.
e Interface; network node interface) In order to realize a dedicated line signal termination function of a trunk interface, a dedicated line signal is transferred using an IP network and terminated by a signaling gateway (SGW), so that a logical function as a network is realized. The configuration and arrangement can be made uniform, and the media gateway / signaling gateway can be constructed economically.

In the present invention, the media gateway (MGW) device is preferably a synchronization unit (6 in FIG. 2).
And a frame part (10) and RTP (Real Time).
e Protocol; an IP connection unit (9) comprising a real-time protocol (11) unit, and the synchronization unit separates an out-of-band signal and an in-band signal from an individual line NNI with an accommodating switching node. Output to the frame unit, and as a reverse process, multiplex a signal from the frame unit and output the multiplexed signal to the individual line NNI.
A line number and a sequence number are given to each extracted individual line control signal, and as a reverse process, a signal is inserted into a frame of data from the RTP unit, and the RT
The P unit converts the out-of-band signal into an IP packet, and performs buffering and I
P packetization is performed, and data extracted from an IP packet received from the IP network is transmitted to the frame unit.

Also, a signaling gateway (SGW)
The device extracts and separates the out-of-band signal and the in-band signal from the IP packet, buffers the in-band signal, and performs the reverse process on the SRTP unit (1 in FIG. 3).
2), a line signal terminator (13) for terminating the out-of-band signal, a number terminator (14) for decoding and terminating the in-band signal, and digit-converting the decoded in-band signal. A telephone number detection unit (15).

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; FIG. 1 is a diagram showing a system configuration according to an embodiment of the present invention. Referring to FIG. 1, a plurality of media gateways (MGW) 2 are installed in an IP network 1, and an NNI (Network No.) using an individual line signaling method is used for an interface with a switching node 5.
DeInterface) 4, and relays trunks and transfers out-of-band signals and individual in-band signals of individual line signals to the signaling gateway (SGW) 3.

Similarly, the signaling gateway (SG
W) 3 is installed on the IP network 1, terminates an individual line signal transferred from the media gateway 2,
And establish a signal sequence.

FIG. 2 is a diagram showing a configuration of the media gateway 2 in one embodiment of the present invention. Referring to FIG. 2, the IP of the individual line signal in the media gateway 2 will be described.
The transfer device will be described.

The media gateway 2 has a synchronization unit 6 and I
A P connection unit 9 is provided.
The TP unit 11 is provided.

The synchronizing unit 6 transmits the out-of-band signal 7 and the in-band signal 8 from the individual line NNI 4 with the exchange node 5 to be accommodated.
Are separated or multiplexed.

The frame unit 10 assigns a line number and a sequence number to each extracted individual line control signal, and inserts a signal into a frame in the reverse direction.

RTP (realtime protocol)
ol) unit 11 converts the out-of-band signal into an IP packet,
It performs buffering to ensure continuity of the in-voice signal and performs IP packetization. In the reverse direction, data extracted from the packet is transmitted. In a packet transmission network such as IP, there is no fixed channel such as ISDN (Integrated Services Digital Network), so a virtual logical channel is defined, and the RTP unit 11
It is packetized and transmitted on this logical channel.

FIG. 3 is a diagram showing a configuration of the signaling gateway 3 in one embodiment of the present invention. The configuration of the individual line signal termination unit will be described with reference to FIG.

An SRTP unit 12 for extracting and separating out-of-band signals and in-band signals from IP packets and buffering the in-band signals or vice versa, and a line signal terminating unit for terminating out-of-band signals 13, a number terminating unit 14 for decoding and terminating the in-voice signal, and a telephone number detecting unit 15 for converting the decoded in-band signal into numerals.

FIG. 4 is a diagram for explaining a communication sequence operation of an individual line signal in one embodiment of the present invention. An example of the communication sequence operation of the individual line signal in one embodiment of the present invention will be described below.

The NNI individual line interface with which the media gateway (MGW) 2 interfaces
4 ((1) in FIG. 4), the synchronization unit 6 extracts the out-of-band signal (SEZ) of each individual line signal, and
Output to

In the frame unit 10 of the media gateway (MGW) 2, the line number and the signal sequence number of the input out-of-band signal are added to the out-of-band signal data and transmitted to the RTP unit 11.

Media Gateway (MGW) 2 RT
The P unit 11 constructs an IP packet from the out-of-band signal data to which the information is added, assigns a destination address (address of the signaling gateway 3), and
(FIG. 4 (2)).

Signaling gateway (SGW) 3
When receiving the packet, the SRTP unit 12 extracts the data and sends it to the line termination unit 13.

The line terminating unit 13 of the signaling gateway (SGW) 3 terminates the out-of-band signal and returns a response signal with the updated sequence number to the SRTP unit 12. The SRTP unit 12 constructs an IP packet and sends it out to the IP network 1 to the source media gateway 2 ((3) in FIG. 4).

Upon receiving the packet, the RTP unit 11 of the media gateway 2 extracts a response signal, a line number, and a sequence number from the IP packet, and sends it to the frame unit 10.

The frame unit 10 of the media gateway (MGW) 2 inserts a response signal at the corresponding line position from the line number and sends it to the synchronization unit 6 together with the sequence number.

The synchronization section 6 of the media gateway (MGW) 2 inserts a response signal into the corresponding trunk of the NNI 4 (SEZACK), and connects the corresponding upstream trunk of the NNI to the in-band signal 8 based on the sequence number.

The frame unit 10 of the media gateway (MGW) 2 assigns the line number of the in-band signal input from the in-band signal 8 and the updated sequence number to the in-band signal data, The data is sent to the RTP unit 11, and the RTP unit 11 sequentially buffers the received data (DIGIT: numerical value) by a capacity capable of guaranteeing the continuity of the signal in the voice band, constructs an IP packet, and sets the destination address to the signaling gateway. (SGW) 3 address is provided and transmitted to the IP network 1 ((6) in FIG. 4).

When the signaling gateway (SGW) 3 receives the packet and recognizes the in-voice signal (numerical value) in the SRTP unit 12, it starts buffering, and when the continuity guarantee is recognized, the in-voice signal is recognized. Extract
The numbers are sequentially sent to the number terminating unit 14.

When decoding the signal in the voice band, the number terminating unit 14 causes the number detecting unit 15 to analyze the signal in the voice band. When the analysis result is obtained, the sequence number is updated, and the reception completion signal is converted to the SRTP signal. To the unit 12.

The SRTP unit 12 of the signaling gateway (SGW) 3 converts the packet into an IP packet, assigns the address of the media gateway 2 as a destination address, and sends the packet to the IP network 1 (FIG. 4). (7)).

Upon receiving the packet, the RTP unit 11 of the media gateway (MGW) 2 extracts a reception completion signal, a line number, and a sequence number from the IP packet, and sends them to the frame unit 10. The frame unit 10 inserts a reception completion signal into the corresponding line position based on the line number, and sends it to the synchronization unit 6 together with the sequence number.

The synchronization section 6 of the media gateway (MGW) 2 inserts a reception completion signal into the corresponding trunk of the NNI 4 ((8) in FIG. 4).

[0040]

As described above, according to the present invention,
In the virtual switching function realized by the cooperation of a group of gateway devices distributed in the IP network, the media gateway device relays the termination processing function of the individual line signal to the signal gateway device by relaying the signal via the IP, thereby realizing the virtual switching function. The resource management at the level can be unified regardless of the signaling method, and the logical configuration as a network can be made uniform.

Further, according to the present invention, since the individual line signal termination circuit is provided only in the signal gateway device, the cost of the media gateway device can be reduced, and the total cost can be reduced significantly.

[Brief description of the drawings]

FIG. 1 is a diagram showing a system configuration according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a media gateway device according to one embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration of a signaling gateway device according to an embodiment of the present invention.

FIG. 4 is a diagram showing a sequence according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 IP network 2 Media gateway (MGW) device 3 Signaling gateway (SGW) device 4 NNI 5 switching node 6 Synchronizing unit 7 Out-of-band signal 8 In-band signal 9 IP connection unit 10 Frame unit 11 RTP unit 12 SRTP unit 13 Line Termination section 14 Number termination section 15 Telephone number detection section

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H04M 3/00 F term (Reference) 5K030 GA19 HA08 HB01 HD03 KA16 MB13 5K033 AA04 BA14 DA05 DB18 5K051 AA05 BB01 CC01 CC04 DD01 DD07 DD11 EE01 EE02 GG02 HH04 HH26 HH27 JJ03 JJ04 JJ12 JJ13 JJ14

Claims (7)

[Claims] 1. A media gateway device which is arranged in an IP (Internet Protocol) network, interfaces with a switching node, and relays connection of a trunk to a server or an IP subscriber existing on the IP network. N using the individual line signaling method for the interface
NI (Network Node Interface)
Receiving an individual line control signal extracted from the NNI individual line,
Individual packet termination in a virtual switching function in an IP network, wherein the individual packet control signal is transferred to a signaling gateway device arranged in the IP network after being converted into an IP packet, and the individual line control signal is terminated in the signaling gateway device. Method. 2. The method according to claim 1, wherein individual line control signals of a plurality of media gateway devices distributed in the IP network are collectively terminated by the signaling gateway device disposed in the IP network. Item I.
Individual line termination method in virtual switching function in P network. 3. A plurality of NNs installed on an IP network and using an individual line signaling system for an interface with a switching node.
I (network node interface), a media gateway device including trunk relay, and means for transferring a dedicated line signal to a signaling gateway device via an IP network; and the media gateway device arranged in the IP network. And a signaling gateway device for establishing a signal sequence with the switching node, comprising: means for terminating a dedicated line signal transferred from the switching device, and a dedicated line termination in a virtual switching function in an IP network. system. 4. The media gateway device according to claim 1, wherein the media gateway device includes a synchronization unit, a frame unit, and an RTP (Real Time Protocol).
And a synchronizing unit that separates an out-of-band signal and an in-band signal from an individual line NNI with an accommodating switching node and outputs the separated signal to the frame unit. Multiplexes the signal from the frame unit and outputs the multiplexed signal to the individual line NNI. The frame unit assigns a line number and a sequence number to each of the extracted individual line control signals, and performs the RTP The RTP unit performs IP packetization of the out-of-band signal and buffering and IP packetization for guaranteeing continuity of the in-band signal. 4. The virtual switching function in the IP network according to claim 3, wherein data extracted from an IP packet received from the IP network is transmitted to the frame unit. Individual line termination system that. 5. The signaling gateway device according to claim 1, wherein
An SRTP unit for extracting and separating an out-of-band signal and an in-band signal from the P packet, buffering the in-band signal, and performing the reverse process; and a line signal termination for terminating the out-of-band signal A number termination unit that decodes and terminates the in-voice signal, and a telephone number detection unit that converts the decoded in-band signal into numbers. Item 5. The individual line termination system in the virtual switching function in the IP network according to item 3 or 4. 6. An NNI dedicated line interface for interfacing with the media gateway device is drawn into the synchronization unit, and the synchronization unit extracts an out-of-band signal of each dedicated line signal, outputs the signal to the IP connection unit, and outputs the frame. In the unit, the line number and the signal sequence number of the input out-of-band signal are added to the out-of-band signal data and transmitted to the RTP unit. , An IP packet is created, and the destination address of the IP packet is used as the signaling gateway device.
To the P network, and in the signaling gateway device, the IP
When a packet is received, the SRTP unit extracts data and sends it to the line termination unit. The line termination unit terminates the out-of-band signal and returns a response signal with an updated sequence number to the SRTP unit. The SRTP unit converts the updated response signal, line number, and sequence number into an IP packet, and sends the destination address of the IP packet to the IP network as the media gateway device. 5. The individual line termination system in the virtual switching function in the IP network according to 5. 7. In the media gateway device,
The RTP unit extracts a response signal, a line number, and a sequence number from the received IP packet, and sends them to the frame unit. The frame unit inserts a response signal at a corresponding line position from the line number, and Along with the number, the synchronization unit inserts a response signal into the corresponding trunk of the NNI, and connects the corresponding trunk on the upstream side of the NNI to a signal in a voice band from the sequence number. The line number of the in-band signal input from the in-band signal and the updated sequence number are added to the in-band signal data and sent to the RTP unit. In the RTP unit, the After sequentially buffering the received data by the amount that can guarantee continuity, I
A P packet is created, and a destination address of the IP packet is transmitted to an IP network as a signaling gateway device.
When the packet is received and the in-voice signal is recognized by the SRTP unit, buffering is started, and when the continuity guarantee is recognized, the in-voice signal is extracted and sequentially sent to the number termination unit. The number terminating unit decodes the in-voice signal, causes the number detecting unit to analyze the in-voice signal, and obtains the analysis result, updates the sequence number and sends a reception completion signal to the SRTP unit. The SRTP unit performs IP packetization in the same manner as the out-of-band signal, sends a destination address of the IP packet to the IP network as the media gateway device, and, in the media gateway device receiving the IP packet, The unit extracts a reception completion signal, a line number, and a sequence number from the IP packet,
The frame unit inserts a reception completion signal into the corresponding line position based on the line number, and transmits the signal together with the sequence number to the synchronization unit. The synchronization unit completes reception to the corresponding trunk of the NNI. 7. The method according to claim 6, wherein a signal is inserted.
The individual line termination system in the virtual switching function in the IP network according to the above.