JP3449919B2 - Button phone system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key telephone system capable of connecting a key telephone and a communication terminal other than a key telephone such as a standard telephone.

[0002]

2. Description of the Related Art As shown in FIG. 12, a key telephone system comprises a main unit 1 in which one to a plurality of telephone lines 2 are accommodated and a plurality of key telephones 3 are connected. Then, with respect to the main device 1, a standard telephone 4 etc.
There are many devices having a configuration that can connect to other standard terminals.

In this specification, unlike the key telephone 3, the standard terminal does not include an LED (light emitting diode) whose lighting, turning off, and blinking are controlled by the control of the main unit 1, and the key telephone. The various button telephone service functions are not available.

The main unit 1 of the conventional key telephone system is
A control unit 5 configured by a microcomputer and controlling the entire main device 1, a switching unit 6 such as a speech path switch, a line interface unit 7, a key telephone interface unit 8, and a standard terminal interface unit 9 are provided. The telephone line 2 is connected to the line interface unit 7.

Button telephone interface unit 8
Has a plurality of ports, and the key telephone 3 is connected to each port. The key telephone 3 receives the LE from the control unit 5 through the key telephone interface unit 8.
It receives control for lighting, turning off, and blinking of D, and for various key telephone service functions. For this control, a dedicated control line is connected between the key telephone 3 and the key telephone interface unit 8 in addition to the communication line, as indicated by the broken line in the figure.

The standard telephone 4 need not be controlled by the control unit 5 and is connected to the standard terminal interface unit 9. No control line is required between the standard telephone 4 and the standard telephone interface unit 9.

[0007]

As described above, in the conventional button telephone system, when the button telephone 3 and the standard telephone 4 are connected, it is necessary to use a separate interface unit for each of them. . Further, in order to realize various advanced key telephone service functions in the key telephone 3, a dedicated control line is required between the key telephone 3 and the key telephone interface unit 8.

After the key telephone 3 is connected to the key telephone interface unit 8 and the standard telephone 4 is connected to the standard terminal interface unit 9, the location can be set for each telephone. This is a limitation, which hinders the user from freely rearranging the telephone.

In view of the above points, the present invention allows a button telephone and a standard terminal such as a standard telephone to be connected to the same interface, which enables the telephone to be freely arranged and has a dedicated control line. It is intended to enable control of a key telephone without damaging advanced services for the key telephone even if it is not used.

[0010]

[Means for Solving the Problems] As a switching system required for the next-generation network, it is necessary to support an increase in information transmission speed, have a variable transmission speed function, and be capable of transmitting multimedia information. The ATM (Asynchronous Transfer)
Mode) exchange method is provided.

In this ATM system, the information sent from the transmitting side to the receiving side is divided into 48 bytes, a 5-byte header is added to this, and high-speed transmission is performed in units called fixed-length cells of 53 bytes. . The header contains information for call identification and information for forming a communication path to the other party. Based on the information in the header, cells are exchanged at high speed by an ATM switch having a hardware configuration. It

On the receiving side, the information in the header of the received cell is confirmed, the data in cell units are concatenated, and the original information is assembled.

FIG. 13 shows the structure of this cell.
This is the case of UNI (User Network Interface). That is, the cell includes a header part HD of 5 bytes (the octet in FIG. 13 is equal to the byte) and a data part DT of 48 bytes. The header HD is a GFC (Generic Fl
ow Control; general flow control), VPI (VirtualPat)
h Identifier; virtual path identifier), VCI (Virtual C
hannel Identifier; virtual channel identifier), PT (P
ayload Type; payload type (indicating the type of user information of 48 bytes), CLP (Cell Loss Prio)
rity; cell loss priority display), HEC (Header Error Con)
trol; header error correction code).

VPI and VCI are ATM routing fields, that is, fields that determine what communication path a cell selects. UNI (User
Network Interface), 1 byte for VPI, VC
2 bytes are allocated to I. VCI is a virtual channel number for call identification, and VPI is an identifier for identifying a communication path.

In the ATM switching network, the VPI and VCI are assigned and set between the calling terminal, the calling side switching apparatus, the relay switching apparatus, the receiving side switching apparatus and the called terminal, thereby forming a virtual path, Communication is performed.

In the key telephone system according to the present invention, the above-mentioned ATM exchange system is applied to the main unit of the key telephone system. In the key telephone system according to the present invention, a first interface unit connected to a digital telephone line and a second interface unit connected to an ATM terminal such as an ATM button telephone or an ATM standard terminal are provided. And an ATM switch for interconnecting the control unit and the first and second interface units with each other, the control unit controlling the entire system including the second interface unit and the second interface unit . Inn of 2
The interface unit includes the ATM terminal and the control unit.
Change the address of the ATM cell exchanged with
In a key telephone system having a function of switching, when the ATM terminal is connected to the second interface unit, the control unit causes the connected A
The TM terminal recognizes whether it is the ATM button telephone or another ATM terminal, and the connected A
When the TM terminal is an ATM button telephone, the ATM button telephone and the second interface unit
During and between said second interface unit and before <br/> SL control unit with bets, different unique PVC respectively
(Fixed virtual channel) is set and the second interface
Between the ATM button telephone and the control unit via the base unit, the different PVCs are used.
It is characterized in that control information is communicated through a fixed communication path .

[0017]

In the present invention having the above construction, the control data from the control unit for the ATM button telephone is A
As a TM cell, it is configured to be able to transmit and receive through an ATM cell bus. That is, it is not necessary to provide a dedicated control line.

The ATM terminal connected to the second interface unit for the ATM terminal (in this specification, the ATM terminal is a concept including an ATM button telephone and an ATM standard terminal) is an ATM terminal. At the time of connection, the control unit recognizes whether it is a key telephone or an ATM standard terminal. This recognition is AT
In the case of the M-button telephone, it can be performed by notifying the main device of a specific control signal at the time of its connection and arranging it so that the control unit can detect it.

The control data path between the ATM button telephone and the control unit is set as a PVC (fixed virtual channel) when the ATM button telephone is connected to the main unit. This PVC does not exist as a physical cable (string), but is a virtual path defined by defining the VCI and VPI of the ATM cell header.

As described above, in the key telephone system of the present invention, the dedicated control line between the key telephone and the main unit can be eliminated, and the key telephone and the standard terminal can be provided with the same interface. To be able to connect to.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a button telephone system according to the present invention will be described below with reference to the drawings.

[Configuration example of button telephone system] FIG.
1 shows an example of the configuration of a key telephone system according to this embodiment, in which a plurality of ATMs are provided in an ATM switching main unit 10.
In this example, two ATM button telephones 3 are used as terminals.
1, 32 and one standard telephone 33 are connected. In addition, as an example of a digital telephone line, INS (Informatio
n Network System) line 20 is connected and configured.

The main unit 10 includes a control unit (hereinafter, CC
11), a line interface unit 12 for connecting to the INS line 20, the ATM button telephones 31, 32 as ATM terminals, and the standard telephone 3
3 for connecting each of the three to the main unit 10 and these units 11, 1
ATM switch 1 for connecting 2 and 13 to each other
And a backboard 14 including 41.

The terminal interface unit 13 is an AT
It has a plurality of, for example, six ports for connecting M terminals, and as described later, either port can accommodate either an ATM button telephone or an ATM standard terminal.

The ATM button telephones 31 and 32 have the same structure, and as shown in FIG. 2, the ATM button telephone control unit 301 and the cell assembling / disassembling unit (hereinafter referred to as CLA).
D (Cell Assembly and Disassembbly) 302
And 303 and numeric keypad 3 for dial input
04, various function button groups 305, and an LED group 306 that is turned on, blinked, and turned off under the control of the main device 10.

The CLAD 302 divides the fixed speed information such as voice sent from the ATM button telephone into 48-byte units, assembles the cells, or disassembles the received cells to restore the voice information and the like. Also, CLAD30
Reference numeral 3 is for assembling and disassembling a cell of control information to be transmitted to and received from the CCU 11.

In the figure, each block of CLAD shows the protocol type of AAL (ATM Adaptation Layer), and AAL1 (AAL type 1) performs cell assembly / disassembly of fixed information such as voice information. , AAL
5 (AAL type 5) is for assembling and disassembling cells such as confirmation connection type data such as control information exchanged with the CCU 11.

The ATM standard telephone set 33 has almost the same structure as the ATM button telephone set, but does not include the LED group 306 under the control of the main unit 10 and the button group 305 for various service functions.

ATM button telephones 31, 32 and AT
The M standard telephone 33 is the terminal interface unit 13
And is connected to the main device 10.

As will be described later, the CCU 11 determines whether the ATM button telephones 31 and 32 are connected (accommodated) to each port of the terminal interface unit 13 or not.
Recognizing whether the standard telephone 33 has been connected (accommodated), and between the ATM button telephones 31 and 32,
The CCU 11 sets a PVC so that local transmission of control data to the ATM button telephones 31 and 32 is performed using the set PVC.

In the key telephone system of this example, for example, an incoming call from the INS line 20 is received by the main unit 10 and notified to each ATM terminal by a cell of control data, and one of the ATM terminals responds. When that AT
The main device 10 exchanges a path between the M terminal and the INS line 20. In addition, for calling, the main device 10 receives the call request cell from the ATM terminal,
The vacancy of the line 20 is confirmed, and the call from the ATM terminal is transmitted to the other terminal through the vacant line channel.

At the time of communication, the voice information from the INS line 20 is made into cells by the line interface unit 12, and the cells are passed through the ATM switch 141 of the backboard 14 to the terminal interface unit 13.
Through the ATM terminal 31, 32, 33. A cell such as voice information from each ATM terminal 31, 32, 33 is sent to the line interface unit 12 through the terminal interface unit 13, ATM switch 141, and ATM cell bus 142, and the cell is disassembled,
It is reconstructed into the original voice information and sent to the INS line 20.

In the key telephone system as described above, the CCU 11, the line interface unit 12 and the terminal interface unit 13, and the CCU 11
As described above, it is necessary to exchange control information between the ATM and the ATM button telephones 31, 32. In order to exchange this control information, usually, a physical unique system control bus (control line) is used, and control is performed by a unique control software interface.

On the other hand, in this embodiment, the AT
By sharing the M cell bus 142 with the system control bus, the CCU 11 can control each unit 12, 13 and ATM button telephone 31, 32 without providing a special system control bus for unit control. . That is, not only the control data between the CCU 11 and each unit 12, 13 but also the local control data between the CCU 11 and the ATM button telephone 31, 32 are
As a TM cell, it is configured to be able to transmit and receive through the ATM cell bus 142.

Therefore, in this embodiment, the PVC is previously set as the system control path or the terminal control path between the CCU 11 and each unit 12, 13 or between the CCU 11 and the ATM button telephone 31, 32.
(Fixed virtual channel) is set and each PVC is
Above, the unit control data and the terminal control data are transmitted and received between the respective units 12 and 13 and the CCU 11 or the ATM button telephones 31 and 32 and the CCU 11 through the ATM switch 141 by the ATM cell.

Then, the transmitted / received control data is SS
COP (Service Specific Connection Oriented Proto)
A communication protocol such as col (service-dependent connection type protocol) enables communication with a higher-level application and various controls in the same manner as data transmitted and received through a conventional system control bus.

The PVC is set as the system control path or the terminal control path, for example, when the system is started up or when the ATM button telephone is connected (at the time of setup).
C is a VPI value and VCI value which are predetermined as a power-up code specific to the unit or ATM button telephone.
This is done by transmitting and receiving ATM cells between the CU 11 and each unit or ATM button telephone. This P
The setting of the VC will be described later in detail.

The detailed structure of the main device 10 including the control information transmission part will be described below.

That is, as shown in FIG. 3, the CCU 11 of the main unit 10 of this embodiment has a CCU control unit 110.
And AAL type 5 for assembling and disassembling control information cells
The CLAD 111 is provided. The CLAD 111 is connected to the ATM cell bus 142 of the backboard 14.
The CCU control unit 110 includes a microcomputer.

There is no physical system control bus on the backboard 14, and the backboard 14 is physically the ATM switch 141 and the ATM in this embodiment.
It consists of a cell bus 142.

As described above, the line interface unit 12 uses the INS (Information Network) in this example.
System) line 20, the INS interface 121, the INS interface control unit 122, and the AAL type 1 CLAD 123 as shown in FIG.
And an AAL type 5 CLAD 124, the CLADs 123 and 124 being the ATM cell bus 1
42 is connected.

The INS interface control unit 122 uses the C
Control data is transmitted / received to / from the CCU control unit 110 through the LAD 124, the ATM cell bus 142 of the backboard 14, and the CLAD 111 of the CCU 11.
It controls the INS interface 121.

The INS interface 121 is connected to the INS line 20 and has an INS interface control section 122.
Interface processing with the INS line 20 under the control of. The CLAD 123 assembles and assembles cells such as voice information transmitted and received through the INS interface 121.
Disassemble.

FIG. 5 shows the terminal interface unit 13
FIG. The terminal interface unit 13 includes a terminal interface control unit 131 and an ATM.
Cell address conversion control unit 132 and C of AAL type 5
And LAD 133.

The terminal interface control unit 131 uses the CL
ATM 133 of AD133 and backboard 14
42, and exchanges control data with the CCU control unit 110 through the CLAD 111 of the CCU 11.

The ATM cell address conversion controller 132
It is provided corresponding to each of the plurality of ports 134 included in the terminal interface unit 13. That is,
The ATM terminal connected to the port 134 is connected to the ATM cell address conversion control unit 132. Further, the ATM cell address conversion control unit 132 is connected to the terminal interface control unit 131 and the CLAD 133. Further, the ATM cell address conversion control unit 132 is further connected to the ATM cell bus 142.

This ATM cell address conversion control unit 132
Indicates each port 1 of the terminal interface unit 13
34 performs the address translation control of the destination at the time of transmitting and receiving the cell of the control information between the ATM terminal accommodated by 34 and the CCU 11, and the cell such as the voice information between each ATM terminal and the line interface unit 12. It controls the address translation of the destination when sending and receiving.

In order to enable transmission / reception of line control data such as call control and call control between the ATM terminal housed in the terminal interface unit 13 and the CCU 11 using the ATM cell bus, , CCU11
From ATM cell bus 142, CLAD111, CLA
ATM cell address conversion control unit 1 via D133
In 32, the routing information for the CCU 11 which is the communication destination (the tag location for the CCU 11 and the accommodation position information of the ATM terminal accommodated in each port 134 of the terminal interface unit 13 thereof) is set. As a result, between each of the ATM terminals 31, 32 and 33 and the CCU 11,
Transmission and reception can be performed via the TM switch 141 and the ATM cell bus 142.

That is, a cell to which an ATM terminal from the CCU 11 is added is changed by the ATM cell address conversion control unit 132 to a cell (no tag) whose address is addressed to each ATM terminal. , To each ATM terminal. Further, a cell of control information such as call information from an ATM terminal is tagged by the ATM cell address conversion control unit 132 and addressed to the CCU 11, is subjected to address conversion, and is sent to the CCU 11 through the ATM cell bus 142 and the ATM switch 141. . Note that the terminal interface unit 13 in the case of this embodiment
The ATM cell address conversion control unit 132 does not need to have the CLAD function because its input and output are all ATM cells. It simply adds / detects tags and VPI / VCI conversion / addition of ATM cell headers. Equipped with a function
It should be good.

[Setting of PVC between Units of Main Unit 10] Next, in the system of FIG. 1, the system control path between each interface unit 12 and 13 and the CCU 11 and the ATM button telephone 31, 32 and CC.
The setting of PVC as a terminal control path with U11 will be described.

FIG. 6 shows the terminal interface unit 13
3 is a sequence diagram for explaining a setting of a PVC between the CCU 11 and the CCU 11. The sequence of FIG. 6 is automatically executed at the time of starting the system in which the main device 10 is powered on.

That is, in this example, the CCU 11
As a power-up code between the terminal interface unit 13 and the terminal interface unit 13, [VPI / V in the header of the ATM cell is used.
The value of CI] is set to [0/8], and this PVC
The control information is transmitted and received as shown in the sequence of FIG. 6, and the PVC for the control information transmission between the CCU 11 and the terminal interface unit 13 thereafter is set.

An example of cell data transmitted and received at this time is shown in FIG.
Shown in. In FIG. 7, for convenience of explanation, as shown in FIG. 7A, the header portion shows only [VPI / VCI],
Information in the information field is added to this.

When the main device 10 is powered on, the terminal interface control section 131 of the terminal interface unit 13 causes the [VPI / VC] via the CLAD 133.
The value of I] is [0/8] and the information field includes the unit accommodation position of the terminal interface unit 13, unit identification information, power-up request information, and the like (see FIG. 7B). To the CCU through the ATM cell bus 142 and the ATM switch 141.
Send to 11.

The CCU control unit 110 receives this via the CLAD 111, and the terminal interface unit 1
Recognize the power-up of 3. Then, the CCU control unit 1
10 is a [VPI for setting a PVC for transmitting / receiving control data to / from the terminal interface unit 13.
/ VCI] value and the ATM cell of the unit control VPI setting request including the power-up confirmation information in the information field (see FIG. 7C), the CLAD111-ATM switch 141 and the ATM cell bus 142-CLAD13.
It transmits to the terminal interface unit 13 through the route of 3.

In the example of FIG. 7, the set [VPI / VC
The value of [I] is [1/12]. The value of [VPI / VCI] of the cell header at this time is [0/8].

The terminal interface unit 13 which has received this unit control PVC setting request cell recognizes that the power up of its own unit has been accepted,
Set the unit control PVC. Then, when the setting is completed, the terminal interface control unit 131
Through the LAD 133, select [VPI / VC in the cell header.
The value of I] is [0/8], and the information field includes an ATM cell including a unit accommodation position of the terminal interface unit 13, unit identification information, power-up setting completion information, and the like (see FIG. 7D). ), ATM
C through cell bus 142 and ATM switch 141
Send to CU11.

AT for completion of PVC setting for this unit control
The CCU 11 receiving the M cell recognizes that the unit control PVC of the terminal interface unit 13 has been set. As a result, thereafter, control data is transmitted and received between the CCU 11 and the terminal interface unit 13 by the set PVC with ATM cells and the ATM cell bus 142 through the CLAD 133, ATM switch 141, and CLAD 111.

FIG. 8 shows the terminal interface unit 13
Shows a sequence of transmitting and receiving control data to and from the CCU 11. ATM cells are used for this transmission / reception, and the ATM switch 141 and the ATM cell bus 142 are used.
Through the [VPI / VCI] of the header
The value of is preset to [1/12] as described above.
And P determined by the value of this [VPI / VCI]
Control data is transmitted and received on the VC.

FIG. 7E is an example of control data addressed to the CCU 11 from the terminal interface unit 13.
FIG. 7F is an example of control data addressed from the CCU 11 to the terminal interface unit 13.

Line interface unit 12 and CC
Similar to the sequence of FIG. 6 described above with respect to U11, when the system is started up, the value of [VPI / VCI] of the header of the cell transmitted / received between both units (terminal interface unit 13 and CCU11 PV between
A value different from C) is set, and the unit control PVC is set. Then, thereafter, the CCU 11 and the line interface unit 12 are held by the set PVC by using the ATM cell through the CLAD 124, the ATM switch 141, and the CLAD 111 through the ATM cell bus.
Control data is transmitted and received between and.

The above PVC setting between the units 12 and 13 and the CCU 11 is performed for all interface units installed in the main unit 10. In this case,
The CCU 11 assigns different [VPI / VCI] values to all units installed in the main device 10.
As a result, the inter-unit control bus that replaces the special system control bus can be realized by the ATM cell bus.

As a communication protocol for exchanging control data between each of the units 12 and 13 and the CCU 11,
For example, SSCOP is used to ensure the reliability of control data. Further, the CLP of the cell transmitted / received when setting the above-mentioned PVC is set to “0”, and the discard priority is set low. This suppresses an increase in traffic such as retransmission of the control signal.

In the above example, the PVC is set by using the PVC which is predetermined for power-up when the main device 10 is started up, but it is not limited to this. .

For example, when the main apparatus 10 is installed and started up,
It is also possible for the operator to set the [VPI / VCI] values that define the PVC between each unit 12, 13 and the CCU 11, respectively.

Further, the CCU control unit 110, the terminal interface control unit 131 and the INS interface control unit 1
It is also possible to provide a control line between the control line 21 and the control line 21 and set the [VPI / VCI] values that define the PVC through the control line in the same manner as described above.

[PVC between ATM button telephone and CCU]
Next, the setting of the PVC for transmitting / receiving the control data to / from the CCU 11 when the ATM terminal is an ATM button telephone will be described. As described below, after connecting to the port 134 of the terminal interface unit 13, the PVC is set to CCU1.
By allowing local control data to be exchanged with the terminal interface unit 1,
Both the ATM standard telephone 33 and the ATM button telephones 31 and 32 can be connected to the respective ports of No. 3.

A is displayed on the terminal interface 13 of the main unit 10.
The processing routine in the CCU 11 when the TM terminal is connected will be described with reference to the flowchart in FIG.

When the ATM terminal 30 is connected to one port 134 of the terminal interface unit 13 of the main device 10 and its power is turned on (step S10).
1), CCU 11 is a terminal interface unit 13
Which of the plurality of ports 134 the ATM terminal is connected to is recognized (step S102). Then, the ATM terminal connected at this time tentatively recognizes that it is an ATM standard terminal (step S103).

When the connected ATM terminal is an ATM button telephone, a setup message including an instruction to start power-up is generated after the connection and power-on of this ATM terminal. On the other hand, A like an ATM standard telephone
In the case of the TM standard terminal, this setup message does not occur.

Therefore, in the next step S104, it is determined whether or not a setup message including power-up has arrived from the ATM terminal connected to the port 134. If it does not arrive, port 1 in step S103
It is confirmed that the terminal connected to 34 is an ATM standard terminal, and the processing routine is exited.

In step S104, the port 134
When it is determined that the setup message including power-up has arrived from the ATM terminal connected to the AT, the AT connected to the port 134 proceeds to step S105.
The M terminal recognizes that it is an ATM button telephone, and in the next step S106, the PVC is set between the connected ATM button telephone and the CCU 11 as a path for control data transmission to be used thereafter. .

After setting this PVC, the next step S10
At 7, the terminal control message is exchanged between the CCU 11 and the connected ATM button telephone, and the terminal number of the ATM button telephone included in the terminal control message is set to the CCU 11 which is the terminal of the connected ATM button telephone. Recognize it as a number and exit this processing routine.

FIG. 10 shows a PVC setting and power-up sequence for controlling the key telephone in this case.

That is, when an ATM terminal is connected to the terminal interface unit 13 of the main device 10, a layer 2 link is established between them and the connected ATM is connected.
The terminal is tentatively recognized as an ATM standard terminal. When the connected ATM terminal is an ATM button telephone, the ATM cell sends a setup message containing power-up information from the ATM cell.

ATM button telephone and CCU1 at this time
Transmission / reception of cells to / from cell 1 is performed via the ATM cell address conversion control unit 132 of the terminal interface unit 13 as described above. That is, the cell [VP
The I / VCI] value conversion is performed in the ATM cell address conversion control unit 132. Note that transmission / reception of a cell between the CCU 11 and the terminal interface unit 13 is performed in a state where a tag is attached to the cell.

In the case of this example, when the ATM button telephone is powered up (when connected to the main unit 10), the ATM
The value of [VPI / VCI] of the cell between the key telephone and the terminal interface unit 13 is set in advance to [0/5] as a standard, for example, and the values of the terminal interface unit 13 and the CCU 11 are different. The value of [VPI / VCI] of the cell between the two is defined as, for example, [1/5].

From the above, as shown in FIG. 10, when an ATM button telephone is connected to one port 134 of the terminal interface unit 13 of the main unit 10, the ATM button telephone sends a [VPI / V
The value of CI] is set to [0/5], and the cell including the information notifying the start of power-up in the information field is CLAD3.
0 3 to the terminal interface unit 13.

When the terminal interface unit 13 receives the power-up start cell from the ATM button telephone, the ATM cell address conversion control unit 132 of the port connected to the ATM button telephone sets the cell [VPI / VCI]. Converts the value to [1/5] and CCU
ATM cell bus 142, AT by adding a tag addressed to 11
The power switch start notification cell is transmitted to the CCU 11 through the M switch 141.

When the CCU 11 receives this, the ATM
Recognize the start of power up of the key telephone. Then, a unique PVC is assigned to the connected ATM button telephone. In this case, this PVC is set by setting the value in the [VPI / VCI] information field of the header of the ATM cell used for transmission of control data. As the value of [VPI / VCI] to be set, as described above, [VPI / VPI / of the header of the cell between the CCU 11 and the terminal interface unit 13 is used.
VCI] value and the terminal interface unit 13 and A
[VPI / VC of the header of the cell with the TM terminal 30
I].

In the example of FIG. 10, [0/20] is set as the value of [VPI / VCI] of the cell header between the terminal interface unit 13 and the ATM button telephone, and the CCU 11 and the terminal interface unit are set. Thirteen
[1/20] is set as the value of [VPI / VCI] of the cell header between and. The latter is a terminal interface unit 1 containing an ATM button telephone.
The VPI / VCI value used as the user frame is set in the ATM cell address conversion control unit 132 of No. 3.

[VPI / VCI] as described above
Is transmitted from the CCU 11 to the ATM key telephone and the terminal interface unit 13, respectively.
For this reason, the CCU 11
A cell in which the value of [VPI / VCI] of the cell transmitted / received to / from the terminal interface unit 13 is included in the information field is transmitted, and the conversion information of [VPI / VCI] is transmitted to the terminal interface unit 13. To

As shown in FIG. 10, first, the CCU 11
Should notify the ATM button telephone [VPI / VC
The cell including the value of [I] in the information field is transmitted. That is, the value of [VPI / VCI] in the header is [1/5]
In the information field, a cell in which a PVC setting value for control information, [VPI / VCI] = [0/20], is added to a tag to which the destination is the terminal interface unit 13 is added. The data is sent from the CCU 11 through the ATM switch 141 and the ATM cell bus 142 to the terminal interface unit 13 that accommodates the connected ATM button telephone.

This cell is received by the ATM cell address conversion control unit 132 of the terminal interface unit 13. Then, this ATM cell address conversion control unit 132
At, the value of [VPI / VCI] of the header is converted and A
It is transmitted to the TM button telephone. That is, the ATM cell address conversion control unit 132 of the terminal interface unit 13 converts the value of [VPI / VCI] of the received cell into [0/5] and removes the tag. Then, the cell is sent to the connected ATM button telephone.

The ATM button telephone receives this cell, parses its information field, and outputs the above [VPI / VC].
The value [0/20] of I] is recognized as the setting data of the PVC as the path for communicating the control data with the CCU 11. And ATM button telephones are
In communication of control data with U11, processing is performed so that the value of [VPI / VCI] in the header part is transmitted as [0/20]. The ATM button telephone has a software application for this process.

After that, the CCU 11 converts the [VPI / VCI] value to be notified to the terminal interface unit 13, that is, the terminal interface unit 13 and the AT.
Value of [VPI / VCI] with M-button telephone [0
/ 20], the terminal interface unit 13 and the CCU
11 and the value [1/20] of [VPI / VCI] with 11 are included in the information field, and a cell is transmitted. A tag is attached to this cell, and its destination is the terminal interface unit 13. The cell path at this time uses the VPC set as the path for the control data between the terminal interface unit 13 and the CCU 11 described with reference to FIG. 6, and the [VPI / VCI] of the header of the cell is used. The value of is [1/12]
Is.

The terminal interface unit 13 sets the cell for notifying the conversion value of [VPI / VCI] to CLAD.
133, holds the converted value of the [VPI / VCI], and transmits and receives the control information between the connected ATM button telephone and the CCU 11 thereafter.
The PI / VCI] value is processed so as to be converted by the held value. Then, the terminal interface unit 13
Sends the cell including the setting completion information in the information field to the CCU 11 through the ATM cell bus 182 through the CLAD 133. The path at this time is also the set PVC, and the value of [VPI / VCI] of the cell is
It is [1/12].

Then, the PVC set as described above is used to communicate between the CCU 11 and the ATM button telephone, and the setting of the user frame connection is completed.

After that, the ATM button telephone notifies the CCU 11 of the power-up setting completion notification including the terminal number of itself by the set PVC route.
That is, the value of [VPI / VCI] of the cell header of the power-up notification from the ATM button telephone is [0/2
0], which is converted to [1/20] by the ATM cell address conversion control unit 132 of the terminal interface unit 13 and transferred to the CCU 11.

In response to this, the CCU 11 recognizes the power-up of the ATM button telephone, and
Recognize the terminal number of the M button telephone. And CCU
11 is a terminal interface unit 13 and ATM
ATM cells having broadcast information, installation data, and volume information as information fields are transmitted to the key telephone by the set PVC. Furthermore, CCU11
Similarly sends the time correction information to the terminal interface unit 13 and the ATM key telephone. After that, the ATM button telephone is in the state of normal operation display.

With the above, the power-up of the ATM button telephone is completed. After that, LE of this ATM button telephone
The local control such as D control and the state information from the ATM button telephone sets the ATM switch 141 and the ATM cell bus 142 by the set PVC path.
Is done through.

FIG. 11 shows this ATM button telephone and CC.
It is a figure which shows the sequence of transmission / reception of control data between U11. Although omitted in FIG. 11, the control data transmitted and received between the terminal interface unit 13 and the CCU 11 is a tagged cell.

Even when an ATM terminal is connected to the other port 134 of the terminal interface unit 13 and the power is turned on, the same processing as described above is performed. When the ATM terminal connected to the port 134 is an ATM standard terminal, the CCU 11 recognizes that it is connected, but does not set the PVC. If the ATM terminal connected to the port 134 is an ATM button telephone,
In the same manner as described above, other A connected to the main device 10
A PVC different from that of the TM button telephone is set, and the set PVC allows local transmission / reception of control data with the CCU 11 through the ATM cell bus.

Thus, according to this embodiment, both the ATM standard telephone and the ATM button telephone can be connected to the terminal interface unit 13.
That is, the terminal interface unit 13 is an ATM
It can be commonly used for standard terminals and ATM button telephones. Therefore, the connection between the ATM standard terminal and the ATM button telephone to the main device 10 is not limited as described at the beginning, and the user can connect the ATM standard terminal and the ATM button telephone even after the system is installed. The position can be changed easily.

Further, a special control line for the ATM button telephone is not required, and when the ATM button telephone is connected, a unique PVC is set and the set PVC is set.
The control data can be exchanged with the CCU 11 through the.

That is, according to this embodiment, the AT
Local control between the M-button telephone and the CCU 11 can also be performed using the ATM cell bus.
Since it is not necessary to provide a local control bus between the key telephone and the CCU, the cost can be reduced.

In the above description of the embodiment, one line of the INS line is connected to the line interface unit 12, but since the line interface unit 12 can accommodate a plurality of lines, It goes without saying that the present invention can be applied to the case where a plurality of lines are accommodated in the line interface unit 12.

The ATM standard terminal is not limited to the ATM standard telephone, but may be a facsimile machine or personal computer capable of sending and receiving ATM cells.

Further, between the CCU 11 and the terminal interface unit and line interface unit,
The control data may not be transmitted via the ATM control bus as in the above-described embodiment, but may be transmitted via a system control bus.

[0100]

As described above, according to the key telephone system of the present invention, the key telephone and the standard terminal can be connected to the common terminal interface unit. Therefore, the arrangement of the key telephone and the standard telephone terminal can be freely set.

According to the present invention, the control data can be transmitted and received between the ATM button telephone and the control unit through the ATM cell bus using the PVC set for each ATM button telephone. A dedicated local control bus is not required, and an ATM button telephone system can be constructed very inexpensively.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing a configuration example of an ATM button telephone according to the embodiment of the button telephone system according to the present invention.

FIG. 3 is a block diagram showing a configuration example of a control unit according to the embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration example of a line interface unit in the embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration example of a terminal interface unit in the embodiment of the present invention.

FIG. 6 is a sequence diagram for explaining setting of a PVC between a terminal interface unit and a CCU in the embodiment of the present invention.

FIG. 7 is a diagram showing an example of data of an ATM cell transmitted and received between a CCU and an interface unit in the embodiment of the present invention.

FIG. 8 is a diagram showing a sequence of transmission / reception of control data between a terminal interface unit and a CCU in the embodiment of the present invention.

FIG. 9 is a flowchart showing a processing routine of a control unit when an ATM terminal is connected to the terminal interface unit in the embodiment of the present invention.

FIG. 10 is a sequence diagram for explaining an exchange between the ATM button telephone and the control unit when the ATM button telephone is connected to the terminal interface unit in the embodiment of the present invention.

FIG. 11 is a sequence diagram for explaining exchange of control data between the ATM button telephone and the control unit in the embodiment of the present invention.

FIG. 12 is a block diagram showing a configuration example of a conventional key telephone system.

FIG. 13 is a diagram for explaining the structure of an ATM cell.

[Explanation of symbols]

10 Main device 11 CCU (control unit) 12 line interface unit 13 Terminal interface unit 14 backboard 141 ATM switch 142 ATM cell bus 20 INS line 31, 32 ATM button telephone 33 ATM standard telephone

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junji Asakura 3-19-3 Nishishinjuku, Shinjuku-ku, Tokyo Inside Nippon Telegraph and Telephone Corporation (72) Inventor Hitoshi Maeda 3-19-3 Nishishinjuku, Shinjuku-ku, Tokyo No. 2 Nihon Telegraph and Telephone Corporation (72) Inventor Osamu Kanagawa No. 24-4 Sakuragaoka-cho, Shibuya-ku, Tokyo Nakayo Communication Co., Ltd. (56) Reference JP-A-11-289336 (JP, A) JP-A 4-96543 (JP, A) JP-A-6-132955 (JP, A) JP-A-9-116554 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04L 12/00

Claims (2)

(57) [Claims] 1. A first interface unit connected to a digital telephone line, a second interface unit to which an ATM terminal such as an ATM button telephone or an ATM standard telephone is connected, and the first and second interface units. A control unit for controlling the entire system including: an ATM switch for mutually connecting the control unit and the first and second interface units; and the second interface unit, The A
A exchanged between the TM terminal and the control unit
A button telephone system having a function of converting an address of a TM cell , wherein when the ATM terminal is connected to the second interface unit, the control unit is configured such that the connected ATM terminal is the ATM button. It recognizes whether it is a telephone or an ATM terminal other than that, and when the connected ATM terminal is an ATM button telephone, the ATM button telephone and the second
Interface unit and the second interface
Between the control unit and Suyunitto each different
Made to set a unique PVC (permanent virtual channel), before
Between serial the ATM key telephone through the second interface unit and with the control unit, wherein each
A button telephone system characterized in that control information is communicated through a communication path defined by different PVCs . 2. The key telephone system according to claim 1, wherein the terminal connected to the second interface unit recognizes whether or not the terminal connected to the second interface unit is the ATM terminal. Button telephone system characterized by performing based on a setup message from.