JPH0548639A - Signaling processing system in atm exchange - Google Patents

Abstract

PURPOSE:To avoid processing disable state of signaling information to the utmost due to a faulty equipment and to reduce a requited cable number with respect to the signaling processing in the ATM exchange by extracting signaling information of an off-hook signal or the like included in a cell from a subscriber interface provided to an input side of switch section of the ATM exchange to send it to a central controller in an exchange. CONSTITUTION:A subscriber interface 11 provided to each subscriber line is provided with a means 12 extracting signaling information stored in an input ATM cell and a means 13 converting format of the extracted signaling information into a format for a central controller respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an asynchronous transfer mode (AT
M) relates to a signal processing method in an ATM exchange for exchanging cells, and more specifically, an off-hook or on-hook signal stored in an ATM cell from a subscriber interface provided between a subscriber line and a switch part of the ATM exchange, The present invention relates to a signaling processing method in an ATM exchange for extracting signaling information such as a signal indicating a data type such as voice and image and sending the signaling information to a central control unit of the ATM exchange.

[0002]

2. Description of the Related Art In recent years, with the spread of data communication, not only conventional voice but also important data has been communicated using a public line, so that high quality transfer and exchange will be possible in a future communication network. Required. Broadband ISDN (B-ISD) is a network for communication services that can provide not only voice and low-speed data but also high-speed data such as moving images.
N) has reached the stage of practical use, and various interfaces are being standardized. Unlike the conventional exchange system, B-ISDN uses asynchronous transfer mode (ATM) to handle information of different speeds such as voice, low-speed data, and moving images in the same way, and further integrates continuous information and burst information. be able to.

In the ATM network, information having different bandwidths is accommodated in a unit of a fixed length called a cell in order to distinguish it from conventional packet communication, and transferred and exchanged. Since the line data and the packet data are multiplexed in a cell unit without distinction, services that require different transfer rates can be flexibly transferred and the transfer path can be efficiently used.

[0004] In the ATM network, user information is divided into a number according to its length, and a header is added to form a cell. The header portion of the cell is, for example, several bytes, and the data portion is about 32 to 120 bytes. VP in the header
There are virtual path identifiers and virtual channel identifiers called I and VCI, which distinguish, for example, from which user the information comes. The user information is made into cells and then multiplexed, transferred, and exchanged on the ATM highway (line). In this exchange, for example, the buffer in the switch of the exchange to which the cell data should be written is designated by the processor of the exchange by the channel number, and the cell data autonomously flows in the network. be called. The receiving side extracts a required cell from the ATM highway based on the channel identifier (VCI), removes the header, and reproduces the user information.

The above-mentioned VPI and VCI are also used for controlling cell switching in the exchange, but in order to reduce the number of transmission bits on the highway, for example, the VPI is provided in the subscriber interface provided in the switch of the exchange. ,
VCI replacement is performed.

FIG. 8 is a configuration block diagram of a conventional example of a signaling processing system in an ATM exchange. In the figure, a conventional example is a switch unit 1 of an ATM switch, subscriber interfaces 2a, ..., 2n as an interface between a subscriber line and the switch unit 1, and a central control unit (CC) 3 switch unit of the switch. ATM adapter (AD that extracts signaling information from the ATM cell input in 1)
P) 4, a signal control (SGC) 5 for converting the format of the signaling information output by the ADP 4 into a format recognizable by the CC 3, the switch unit 1 as a speech path, and the subscriber interface 2a,
..... Central control-speech path (CC as interface between 2n and central control unit 3
-SP) interface 6.

In FIG. 8, A input from the subscriber side
For the TM cell, the subscriber interface 2a, ...
················································, 2n, for example, VPI and VCI conversion is performed, and the converted cell is input to the switch unit 1. Further, the subscriber interfaces 2a, ..., 2n maintain the lines between the subscriber side terminal and the subscriber interface, the line between the subscriber interface and the switch unit, and the hardware itself in the subscriber interface. Then, the information indicating the line status and the hardware status is sent to the CC 3 via the CC-SP interface 6 as the maintenance information.

The ATM adapter 4 extracts the signaling information stored in, for example, a few bits or more from the beginning of the cell input to the switch unit 1, and the extracted signaling information is, for example, from the ATM cell format. LA as a link access protocol on the D channel
The data is converted into a PD (64 Kbps) format by the SGC 5 and sent to the central controller 3.

[0009]

However, in the conventional signaling processing system as shown in FIG. 8, the ATM adapter 4 for extracting the signaling information stored in the ATM cells sent from many subscribers, and Since there is only one signal control 5 each, there is a problem that if any one of them fails, the processing of signaling information cannot be performed at all.

Further, in FIG. 8, there is a problem that the number of cables required increases because the signaling information is sent to the central control unit by a route completely different from the maintenance information sent through the CC-SP interface 6. there were.

It is an object of the present invention to avoid as much as possible the inability to process signaling information due to a device failure and to reduce the number of cables required.

[0012]

FIG. 1 is a block diagram showing the principle of the present invention. The figure shows an ATM equipped with one or more subscriber interfaces 11 provided corresponding to each subscriber line for inputting an asynchronous transfer mode (ATM) cell input from the subscriber to the switch unit 10 of the exchange. It is a principle block diagram of the signaling processing system in a switching system.

FIG. 1A is a block diagram showing the principle of the first invention. In the figure, signaling information extraction means 12
Are provided in each subscriber interface 11,
Signaling information such as on-hook and off-hook signals stored in the input ATM cell is extracted from the ATM cell. Similarly, the format exchange means 13 is also provided in each subscriber interface 11, and converts the format of the signaling information extracted by the signaling information extraction means 12 into the format for the central control unit of the ATM exchange.

FIG. 1B is a block diagram of the principle of the second invention. In FIG. 1, the principle of the first invention is shown in FIG.
Unlike (a), of the signaling information extraction means 17 and the format conversion means 18, only the signaling information extraction means 17 is provided in each subscriber interface 16, and the signaling information extraction means 17 inputs the same as described above. The signaling information stored in the ATM cell is extracted. The format conversion means 18 is provided, for example, between each subscriber interface 16 and the central control unit of the ATM exchange, and converts the format of the signaling information output by the signaling information extraction means 18 into a format for the central control unit.

[0015]

In FIG. 1A showing the principle of the first invention, signaling information is extracted in the subscriber interface 11 and the format of the extracted information is exchanged.
The signaling information after the format conversion is multiplexed with the maintenance data of the subscriber interface 11, for example, and is sent to the central control unit 3 of the exchange through the central control-speech path interface 6 of FIG. Thereby, for example, the ATM adapter and the format conversion means 1 as the signaling information extraction means 12
Signal control as 3 will be provided for each subscriber line in each subscriber interface.
Further, a cable from the switch section 1 as shown in FIG. 8 to the central control unit 3 via the ATM adapter 4 and the signal control 5 is unnecessary.

In FIG. 1 (b) showing the principle of the second invention, the signaling information extracted in the subscriber interface 16 is format conversion means provided between each subscriber interface and the central control unit. It is sent to, for example, the signal control 18 and is converted in format and then transferred to the central control unit.

In the first invention shown in FIG. 1A, the signaling information is multiplexed with the maintenance information of each subscriber interface and transferred to the central control unit 3 via CC-SP6 of FIG. 8, for example. Therefore, the amount of data received by the central control unit 3 from the CC-SP interface 6 increases, and the amount of processing by the central control unit increases. However, in FIG. 1 (b), as in the conventional example of FIG. Since the information is sent to the central control unit via different routes via the SGC, the processing load on the central control unit is reduced.

[0018]

2 is a block diagram showing the configuration of an embodiment of the first invention. Comparing this figure with the conventional example of FIG. 8, an ATM adapter (ADP) for extracting signaling information,
A subscriber interface 21a provided with a signal control (SGC) for converting the format of the extracted signaling information into an interface for the central control unit (CC) 25 of the exchange, for each subscriber line ,.
..., provided inside 21n respectively, and ADP + S
The signaling information extracted by the GCs 22a, ..., 22n and converted in format is multiplexed with the maintenance information of the subscriber interface as described later, and is transmitted via the central control-speech interface 24 to the central controller (CC). Sent to 25. The cells from which the signaling information has been extracted are input to the switch 23 from the subscriber interfaces 21a, ..., 21n.

FIG. 3 shows an embodiment of a maintenance data transmission signal of the subscriber interface sent from each subscriber interface 21a, ..., 21n to the CC 25 via the CC-SP interface 24 in FIG. In the figure, 1 for sending maintenance data
The frame length of the frame is, for example, 4 msec, but this cycle is such that there is still a spare area even if the maintenance data is stored, and by inserting the signaling data extracted by the ATM adapter into the free area. , Each subscriber interface 2 in the conventional example of FIG.
a ... 2n to CC-SP interface 6
It is possible to send signaling information by utilizing the signal line to the terminal as it is.

FIG. 4 shows subscriber interfaces 21a, ..., 21n provided in FIG. 2 for the detail line of each subscriber interface 21a ,.
・ ADP + SGC provided inside 21n
The signaling information extracted by 22a, ..., 22n and converted in format is multiplexed with the maintenance information of the subscriber interface as described later, and is transmitted via the central control-speech interface 24 to the central controller (CC). Sent to 25. The cells from which the signaling information has been extracted are input to the switch unit 23 from the subscriber interfaces 21a, ..., 21n.

FIG. 3 shows an embodiment of the maintenance data transmission signal of the subscriber interface sent from each of the subscriber interfaces 21a, ..., 21n to the CC 25 through the CC-SP interface 24 in FIG. In the figure, 1 for sending maintenance data
The frame length of the frame is, for example, 4 msec, but this cycle is such that there is still a spare area even if the maintenance data is stored, and by inserting the signaling data extracted by the ATM adapter into the free area. , Each subscriber interface 2 in the conventional example of FIG.
a ... 2n to CC-SP interface 6
It is possible to send signaling information by utilizing the signal line to the terminal as it is.

FIG. 4 is a detailed block diagram of the subscriber interfaces 21a, ..., 21n shown in FIG. In the figure, a subscriber interface 21 is a line with a subscriber terminal, a line with a switch unit 23,
And maintenance information 31 indicating the hardware state of the interface itself, an ATM adapter 32 for extracting signaling information from an input ATM cell, and a signal control (SGC) 33 for converting the format of the extracted signaling information. A memory 34 for temporarily storing the maintenance information 31, a memory 35 for temporarily storing the format-converted signaling information, a selector 36 for switching and outputting the stored contents of the memories 34, 35, and the maintenance shown in FIG. It is composed of a controller 37 for producing a multiplexed signal of data and signaling data. In FIG. 4, parts in the subscriber interface 21 that are not directly related to the present invention, such as parts for replacing VPI and VCI, are omitted.

FIG. 5 is a detailed block diagram of the central control-speech path interface 24 shown in FIG. In the figure, the CC-SP interface 24 includes an elastic memory 40 for temporarily storing the maintenance information from the switch unit 23, and multiplexing of maintenance data and signaling data from the respective subscriber interfaces 21a, ..., 21n. The elastic memory 41 for temporarily storing the encoded information, the selector 42 for switching the outputs of the two elastic memories 40, 41, and the multiplexer 42 outputting the multiplexed signal in response to the data transfer request from the central controller 25. It is composed of a controller 43 for performing the operation. This allows
The maintenance data transferred from the switch unit 23 and the multiplexed signal of the maintenance data and the signaling data transferred from each subscriber interface are multiplexed and transmitted in accordance with the bit rate on the central controller 25 side. ..

FIG. 6 is a configuration block diagram of an embodiment of the second invention. Comparing this figure with FIG. 2 showing an embodiment of the first invention, each subscriber interface 44a, ..., 44
.., 45n, and a signal control 47 for converting the format of signaling information is provided outside each subscriber interface as in the conventional example of FIG. .. The signaling information extracted by the ATM adapters 45a, ..., 45n inside each subscriber interface is multiplexed with the maintenance data of the subscriber interface as in FIG. Sent to 48.

In the first aspect of the invention shown in FIG. 2, the CC-SP interface 24 includes all the multiplexed signals of maintenance information and signaling information from each subscriber interface and the maintenance information from the switch section 23. To the central controller 25. CC-SP
Between the interface 24 and the CC 25, for example, a control signal or the like for switching the switch unit 23 is also transmitted, so that C is increased in order to increase the signal amount during this period.
There is a problem that the processing by C25 becomes difficult. In contrast, in FIG. 6, the subscriber interface 44
The multiplexed signal of the interface maintenance information and the signaling information from a, ...
This problem is solved because it is sent to CC 48 by a different route via.

FIG. 7 is a detailed block diagram of the embodiment of the second invention of FIG. In the figure, for simplicity, only one subscriber interface 44 is shown. Maintenance information 51 is held in the subscriber interface 44, and the maintenance information and the signaling information extracted by the ATM adapter 45 are stored in FIG.
In the same manner as in (1), the signal is multiplexed by the selector 53 under the control of the controller 52, and the multiplexed signal is sent to the SGC 47. The SGC 47 is a format conversion unit 54 that performs format conversion, and an elastic memory 55 that temporarily stores the multiplexed signal after the format conversion and substantially performs bit rate conversion with the CC 48 side.
It consists of Further, the switch unit 46 holds maintenance information 56, and this maintenance information is temporarily stored in the elastic memory 57 in the CC-SP interface 49, subjected to bit rate conversion, and output to the CC 48.

[0027]

As described above in detail, according to the present invention, since one ATM adapter for extracting signaling information is provided corresponding to each subscriber line, one A
Even if the TM adapter fails, it is possible to prevent the entire system from going down. Further, in the first invention, since the signaling information is also transmitted through the central control-speech path interface, it is possible to reduce the cable to the central control device, and in the second invention, from this interface. Since the amount of data transferred to the central control unit is reduced, the processing load on the central control unit can be reduced.

[Brief description of drawings]

FIG. 1 is a principle block diagram of the present invention.

FIG. 2 is a block diagram showing a configuration of an embodiment of the first invention.

FIG. 3 is a diagram showing an example of a maintenance data transmission signal from each subscriber interface.

FIG. 4 is a block diagram showing a detailed configuration of a subscriber interface in FIG.

5 is a block diagram showing a detailed configuration of a central control-speech path interface in FIG.

FIG. 6 is a block diagram showing a configuration of an exemplary embodiment of the second invention.

FIG. 7 is a block diagram showing a detailed configuration of the embodiment of FIG.

FIG. 8 is a block diagram showing a configuration of a conventional example of a signaling processing system in an ATM exchange.

[Explanation of symbols]

10,23,46 Switch unit 11,16,21,44 Subscriber interface 12,17 Signaling information extraction means 13,18 Format conversion means 22 ATM adapter + signal control 24,49 Central control-speech path interface 25,48 Central control Device (CC) 45 ATM adapter 47 Signal control (SGC)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H04Q 11/04 303 Z 8843-5K

Claims (6)

[Claims] 1. An ATM switching system comprising one or more subscriber interfaces (11) for allowing an asynchronous transfer mode (ATM) cell input from a subscriber to be input to a switch section (10) of a switch. Signaling information extracting means (12) for extracting the signaling information stored in the input ATM cell in the interface (11), and format converting means for converting the format of the signaling information into the format for the central control unit of the exchange. (13) A signaling processing system in an ATM exchange characterized by comprising: 2. From the subscriber interface (11), the central controller and the subscriber interface (1)
The maintenance data of the subscriber interface (11) and the signaling information after the format exchange are multiplexed via a central control-speech path interface as an interface between 1) and the switch unit (10), and The signaling processing system in an ATM exchange according to claim 1, wherein the signaling processing system sends the signal to a central control unit. 3. The central control-speech path interface is the subscriber interface (1).
1) storing multiplexing information of signaling information after format exchange and maintenance data sent from 1)
Elastic memory, a second elastic memory for storing maintenance data sent from the switch unit (10), and outputs of the first and second elastic memories for data transfer on the side of the central controller. 4. A signaling processing system in an ATM exchange according to claim 3, further comprising a selector and a controller for multiplexing according to speed. 4. An ATM switching system comprising one or more subscriber interfaces (16) for allowing an asynchronous transfer mode (ATM) cell input from a subscriber to be input to a switch section (10) of the exchange. The interface (16) includes signaling information extracting means (17) for extracting signaling information stored in the input ATM cell, and the one or more subscriber interfaces are provided after the signaling information extracting means (17). (16) A signaling processing system in an ATM exchange, comprising format conversion means (18) for converting the format of signaling information output from (16) into a format for the central control unit of the exchange. 5. The subscriber interface (16) multiplexes the signaling information and maintenance information of the subscriber interface (16) and outputs the multiplexed information to the format conversion means (18). Item 4. A signaling processing method in an ATM exchange according to Item 4. 6. The format conversion means (18) comprises:
A format conversion unit that performs the format conversion, and an elastic memory that stores the output of the format conversion unit and that outputs the stored contents in accordance with the data transfer rate on the side of the central controller are provided. A signaling processing method in an ATM exchange according to claim 4.