JPH07131551A - Subscriber's private communication system - Google Patents

Abstract

PURPOSE:To unnecessitate the centralized control using a PBX by providing a call control message monitoring means on each terminal equipment together with a means which fetches the control information on a transfer medium and sets and cancels the extension and outside line communication channels. CONSTITUTION:The control information which includes the information on the dead channels of a transfer medium shared by plural terminal equipments 3 is circulated on the transfer medium. Each equipment 3 monitors a call control message by a monitoring means 1 and then fetches the control information circulating on the transfer medium by a control means 2 after detecting a setting or canceling request for the extension or outside line connection. Then the extension/outside line signal channels are set/canceled based on the information on the dead channels included in the control information. Therefore it is possible to attain the extension communication among equipments 3 and the outside line communication secured with a public network via a terminal controller 4 without using any PBX in a subscriber's private network where a ring-shaped or bus-shaped transfer medium is shared by plural equipments 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
External communication system.

[0002]

2. Description of the Related Art Communication networks are classified into public networks such as telephone networks and home networks (user premises networks). A general telephone subscriber is connected to a public network through a subscriber line, but when a large number of users are concentrated in one place such as a large company, a private branch exchange (PBX) is located in the premises. Is installed to save the number of lines between the terminal and the exchange.

In recent years, B-ISDN (broadband ISDN) has been studied, and the basic bit rate of the subscriber line is 150 Mb /
It was decided to be s. Since the 150Mb / s user network interface can simultaneously provide more than 2000 64Kb / s voice calls, its effective usage is an important subject for study.

As a technique for realizing this B-ISDN, A
There is TM (Asynchronous Transfer Mode). In ATM, all traffic is transferred in a fixed length packet of 53 octets, and the channel is identified by VPI / VCI in the header field of the ATM cell.

[0005]

As a method of effectively utilizing a subscriber line of 150 Mb / s, a method of installing a PBX in a user's premises as in the past can be considered, but the PBX is very costly. This is not an appropriate method if the number of terminals accommodated is not very large. In addition, since it is necessary to connect the lines in a star pattern between the PBX and the terminals, there is a drawback that the number of cables to be laid increases and the cost increases.

On the other hand, even when the terminal does not provide a call processing function in the user premises network and the terminal performs extension communication, the call processing unit of the public network is notified of the requested bandwidth and the call processing of the extension communication can be performed by the public network. It is conceivable, but the load on the public network increases accordingly, so this is not a desirable method.

An object of the present invention is to provide a PB in a home network in which a plurality of terminal devices share a ring-shaped or bus-shaped transmission medium.
It is to realize extension communication between terminals and external communication with a public network without using X.

[0008]

In a home network composed of a plurality of terminal devices sharing a transmission medium, each terminal device 3 (see the principle explanatory diagram of FIG. 1, the same applies hereinafter) monitors the call control message. 1 and the monitoring means 1 detects a connection setting / release request for an extension line or an outside line, fetches management information circulating on the transmission medium, and communicates the extension line / outside line based on the information indicating the empty channel of the management information. It has a management means 2 for setting / releasing channels.

Further, a terminal management device 4 is arranged at the contact point between the home network and the public network, and the terminal management device 4 has the same structure as the terminal device 3, and further, the idle channel of the transmission medium of the home network is public. It has the function of notifying the exchanges of the network. The terminal management device 4 is connected to the public network via the network terminating device NT1.

[0010]

According to the present invention, for example, a band management token indicating an allocated band and a VCI management indicating an allocated virtual channel on a transmission medium (ring-shaped, bus-shaped transmission path) shared by a plurality of terminal devices. A token or a band / VCI management token including both is circulated. Then, the management means 1 of the terminal device requesting the setting / release of the connection captures the band management token, and when the communication request is the connection setting request and the band management token has a free band, the band management token is allocated. The bandwidth to be newly used is added to the allocated bandwidth, and when the communication request is a release request, the bandwidth to be released is subtracted from the allocated bandwidth of the bandwidth management token.

As a result, the band and channel of the transmission medium can be distributed and managed in each terminal device 3. In addition, each terminal device 3
Can know whether or not there is a vacancy in the band of the transmission medium, so that useless calling can be prevented. Also, when changing the band, it can be easily realized by the same procedure as above.

In the case of extension communication between terminals, the calling terminal device 3 captures the VCI management token, and if there is a free VCI, the point-to-point signal at which only the calling / ending terminal 3 terminates the VCI. After securing as the VCI of the channel for use, the newly secured VCI of the VCI management token is changed to allocated. Then, the VCI of the point-to-point signal channel is added as a parameter of the connection setting request message, and broadcast to all terminals using the broadcast type signal channel.

When the destination terminal device 3 monitors the broadcast type signal channel by the monitoring means 1 of its own device and detects a connection setting request message having its own device as the destination address,
A response message is returned using the VCI signaling channel added to the connection setup request message. After that, both the originating and terminating terminals exchange call control messages using the point-to-point signaling channel terminated by the partner terminal.

On the other hand, in the case of outside line communication, the terminal management device 4 located at the contact point between the home network and the public network notifies the exchange of the public network of the bandwidth used and the VCI used of the home network, and the public network is switched. Free V notified to the exchange when an incoming call from
The CI is added to the connection setting request message as a signal channel (point-to-point signal channel) for transmitting a call control message, and the connection setting message is broadcast to all terminal devices using the broadcast type signal channel.

The destination terminal device 3 uses the signaling channel designated by the terminal management device 4 to return the response message to the exchange of the public network. The exchange monitors the vacant channel (vacant VCI) notified from the terminal management device 4,
The response message sent from the destination terminal device 3 is received.

As described above, by exchanging the call control message by using the signaling channel peculiar to the originating and terminating terminal devices, the extension communication can be realized without using the PBX or the like. In addition, external line communication with the public network can be similarly realized.

When a plurality of terminal devices 3 respond to the connection setting request message from the calling terminal device 3 (for example, a three-way call), the calling terminal device 3 adds the call identification information to the connection. The setting request message is broadcast to all the terminal devices 3 using the broadcast type signal channel.

Each of the plurality of destination terminal devices 3 that intends to establish a connection with the source terminal device 3 secures a signal channel (point-to-point signal channel) terminated only by itself and the source terminal device, A response message to which call identification information designated by the calling terminal device is added is returned using the secured point-to-point signal channel.

The calling terminal device 3 monitors the signal channel of the transmission medium, and detects a response message added with the call identification information sent from its own device and sent back from the plurality of called terminal devices 3. Then, when the response message to which the call identification information is sent, which is transmitted by the own device, is detected, the signal channel detecting the response message is recognized as the point-to-point signal channel terminated by each destination terminal device 3, and The call control message is sent to each destination terminal device using the point-to-point signaling channel.
Thereafter, the calling terminal device and the plurality of called terminal devices exchange call control messages using their point-to-point signaling channels. As a result, 1-to-N communication can be realized without using the PBX or the like.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 2A and 2B are diagrams showing the configuration of a home network (user premises network) of an embodiment of the present invention connected to a ring or a bus.

Each terminal device (hereinafter referred to as a terminal) 11 is connected to a ring (ATM ring) or a bus-shaped transmission medium and manages those terminals by an SMT (System Manager).
t) 12 to the network terminating device (NT1). Each of these terminals 11 and SMT 12 hunts a band / VCI management token, which will be described later, and uses the band / VC.
It has a function of securing I and realizing internal communication and external communication. Note that these functions may be separated from the terminal as a media access device (MAU), the media access device may be connected to a ring or a bus, and the terminal may be connected to each media access device.

Next, FIG. 3 is a diagram showing the structure of an ATM ring, which shows a plurality of media access devices (MA).
U) 13 and the SMAU 14 terminating the signal to or from the public network are connected to the ATM ring.

VP (Virtual Path) 0 is a network terminating device NT
SG1 #, which is a virtual channel VC (Virtual Channel) for call control determined by a meta-signaling procedure (CCITT recommendation Q.142X) between NT1 and SMAU14. 1 to
The main information VCs IN1 # 1 to IN1 dynamically set between the SG2 # 1 and the NT1 and each MAU13.
1 # 2.

Note that M flowing through SG1 # 1 to SG2 # 1
SETUP (calling) message from AU13 is SMA
Passes through U14 as it is, but SETUP from the public network
The (incoming call) message is controlled by the SMAU 14.

VPi is a logical path that connects the MAU 13 and the SMAU 14, and is one extension call control VC that is preset between the SMAU 14 and the MAU 13.
G2C, SG2 # i which is an extension call control VC used by the SMAU 14 for receiving a call control signal, and SG2C
IN2 # i which is a VC for main information of extension connection dynamically set by the above call control, SMAU 14 and MA
Band / VCI management VC preset with U13
And the BVM.

SG2C is a broadcast type signal channel [CCITT
This is equivalent to GBSVC (Grobal Broadcast Signaling VC) of I.311] of the I.311], and the call control information (S
ETUP messages, etc.) are all MAU13 / SMAU14
Can be received at. Also, only one band / VCI management token circulates in the BVM.

FIG. 4 is a diagram showing the structure of a band / VCI management token that circulates in a BVM.
The TM header is stored, the used (allocated) bandwidth is stored in the following 4 bytes, the information indicating the empty / closed state of the VCI of 320 channels is stored in the following 320 bits, and the CRC code for error correction is stored in the last 4 bytes. Is stored.

The used band stores the used band for extension lines and the total used band, and more specifically, the outside line band is secured by suppressing the below-mentioned extension band within a certain value.

Next, the call control process performed by each terminal 11 and SMT 12 of FIG. 2 will be described with reference to FIG. Call setup request message SETU from the terminal 11 or the public network
When P is sent, the terminal 11 or the SMT 12 is sent to FIG.
In step S1 of 1., the bandwidth / VCI management token that circulates the BVM is hunted. Then, in the next step S2, the bandwidth / VCI usage state of the bandwidth / VCI management token is checked to determine whether or not the bandwidth and VCI are free.

If there is no available band / VCI, the process proceeds to step S3, the originating terminal is notified that the call cannot be made, and the communication is terminated. On the other hand, if there is a vacant band and VCI,
In step S4, the SETUP message is transmitted to the line, the band newly used as the band / VCI management token band information is added in step S5, and the bit corresponding to the VCI to be used is set to "1", and then step S
The band / VCI management token updated in 6 is released. Then, in step S7, an ALERT message notifying that the called party is calling is awaited.

Next, a call control signal procedure at the time of extension mutual communication and at the time of an external line incoming will be described more specifically. In the extension intercommunication, the calling terminal is a broadcasting type signal channel (GBSVC: VCI).
= 2) is used to send a SETUP message, the other terminals monitor the broadcast type signal channel, and if a SETUP message addressed to their own terminal is received, ALERT (A
lerting), CONN (Connect) messages, etc. are returned by a terminal-specific channel for point-to-point signals. There are the following two methods for determining the point-to-point signal channel.

Method 1: When the power of each terminal is turned on or when the terminal is inserted, the signal channel terminated by each terminal is determined by the meta-signaling procedure. Then, when performing extension communication, the calling terminal adds the VCI number (P-P SVCI) of the signal channel (own point-point signal channel) terminated by the own terminal in the SETUP message, and the destination terminal By sending the response message on the point-to-point signaling channel designated by the calling terminal, only the calling terminal can terminate this reply message.

Method 2: The calling terminal hunts the band / VCI management token, and not only the VCI for main information but also the terminal or the called terminal terminates point-point signal VCI
To win. And the point-V for point signal
The CI is added to the SETUP message to notify the destination terminal of the signal VCI terminated by the calling terminal. The signal VCI terminated by the destination terminal may be notified when the destination terminal hunts the VCI management token and returns a response message to the source terminal,
The calling terminal also hunts the signal VCI of the called terminal and SETUP
You may notify by message.

In the following, the extension call when each terminal operates based on the above-mentioned method 2 in which the calling terminal hunts the band / VCI management token and acquires the point-to-point signal VCI shared by the calling and destination terminals The call procedure will be described with reference to FIG.

In step S11 of FIG. 6, the calling terminal sets the band /
The VCI management cell (token) is hunted, and in the next step S12, it is determined whether or not there is a vacancy in the VCI of the band / VCI management cell. If there is a vacant VCI, the vacant VCI is selected in step S13 and the selected VCI is selected.
A point-to-point signal VC that is shared by the originating and terminating terminals
It is added to the SETUP message as I and transmitted to the broadcast type signal channel.

For example, when the calling terminal selects VCI = # 20 as the VCI for point-to-point signal,
As the SETUP message, “SETUP (CR # 0
+ A, DA, departure P-P SVCI: # 20) "," on
VCI = 2 in VPI = i ”, that is, VCI = i, and VCI = 2 is transmitted to the broadcast type signal channel of VCI = 2.
CR # corresponds to Call Refernce of CCITT Recommendation Q.931, and is used as an identifier (call identification information) of the call that the signaling message is trying to control. The issuing side sets the flag to "0" to arbitrarily select the call identification number, and the receiving side sets the flag to "1" to use the identification number selected by the issuing side. In addition, VCI = 2,
VCI number of broadcast signal channel, DA (Dastina
tion Address) is the destination terminal address, for example, CCI
TT E. 164 addresses are assumed. Also VPI
= I represents an extension communication VP.

Each terminal compares the DA of the SETUP message sent to the broadcast signal channel in step S14 with its own address, and the terminal having the matching address is SE.
ALER indicating that a call is being made using the VCI for point-to-point signaling specified in the TUP message
The T message is returned to the calling terminal, and when the off-hook is detected, the CONN message is returned.

For example, when VCI = 20 is designated as the VCI for point-to-point signal by the SETUP message, the destination terminal sets "ALERT (CR # 1 + a)" as the ALERT message to VCI = 20 with VPI = i. Send to. When the destination terminal goes off-hook, that is, when the user's response is detected, "CONN
(CR # 1 + a) "is sent to the same signal channel.

On the other hand, when the calling terminal receives the CONN message sent to the signaling channel of VCI = 20, it sends "CONN ACK (C
R # 0 + a) "to the same signaling channel, namely VPI
= I VCI = 20.

In the present embodiment, if an extension communication request is accepted within a range in which the extension / use bandwidth of the band / VCI management cell does not exceed the predetermined upper limit value, and the extension use bandwidth exceeds the predetermined upper limit value, The extension communication request is rejected. As a result, it is possible to secure the band for the outside line and prioritize the call to the outside line or the incoming call from the outside line.

Further, by providing a cell regulation unit at the contact point between each terminal and the transmission medium to regulate the flow rate of the ATM cells sent from each terminal within the declared usage band, the usage band of other terminals is guaranteed. be able to.

Next, an extension call procedure when each of the originating and terminating terminals dynamically determines its own point-to-point signal channel will be described with reference to FIG. In step S21 of FIG. 7, the calling terminal hunts the band / VCI management cell, and in the next step S22, it is determined whether or not there is a vacancy in the signaling channel. If there is a vacancy in the VCI, the specific VCI is selected in step S23, and the band / V
The bit of the corresponding VCI of the CI management cell is changed to "1". Then, the selected point-to-point signal VCI number is added to the SETUP message and transmitted to the broadcast signal channel.

For example, when the calling terminal selects VCI = # 20 as the VCI for point-to-point signal, S
As an ETUP message, “SETUP (CR # 0 +
a, DA, originating P-P SVCI: # 20) ", VPI
= I, VCI = 2.

Each terminal compares the DA of the SETUP message sent to the broadcast type signal channel in step S24 with its own address, and the terminal which matches is compared with step S2.
Hunt the band / VCI management cell at 5. Then, in step S26, the point-to-point signal VCI used by the destination terminal is selected, and the bit of the corresponding VCI of the band / VCI management cell is changed to "1".

For example, when the destination terminal selects VCI = 30 as its own point-to-point signal VCI, an "ALERT (CR # 1 + a, destination P-P SVC
I: # 30) "is sent to the point-to-point signal channel of the calling terminal, VPI = i, VCI = 20.
In addition, if the destination terminal detects off-hook, the CONN
Send the message to the same signaling channel.

On the other hand, the calling terminal sends ALER from the called terminal with VCI = 20 of its own point-point signaling channel.
When the T message is received, the signal channel of the destination terminal is recognized from the VCI number added to the ALERT message. When the CONN message from the destination terminal is received, the response "CONN AC
K ”message, the point specified by the destination terminal −
VCI = 3 of VPI = i which is a point signal channel
Send to 0.

In this case, the originating and terminating terminals each have a band / V
It hunts the CI cell, selects the VCI that is vacant at that time as the VCI for the point-point signal of its own terminal, and notifies the selected terminal of the VCI for the point-point signal to the other terminal. The destination terminal can send and receive a call control message using these signaling channels to realize extension communication.

Next, an extension call procedure when the calling terminal determines the point-to-point signal channels of both the calling and terminating terminals will be described with reference to FIG. Step S31 of FIG.
Then, the calling terminal hunts the band / VCI management cell, and in the next step S32, the band / VCI management cell has an empty VCI.
It is determined whether or not When there is a vacant VCI, in step S33, the calling terminal selects the point-to-point signal VCI of both the calling and terminating terminals.

For example, the calling terminal may have VCI = 20 and VCI as VCIs for point-to-point signals of both the calling and terminating terminals.
= 30 is selected, the SETUP message with those VCI numbers added, “SETUP (CR # 0 +
a, DA, departure P-P SVCI: # 20 arrival P-P S
VCI: # 30) to the broadcast signal channel (VPI =
i, VCI = 2).

In step S34, each terminal monitors the SETUP message sent to the broadcast type signal channel,
If the DA matches the terminal address of its own, it sends an ALERT message to the point-to-point signal channel of the calling terminal to inform that it is calling.

For example, V is used as the signal channel of the calling terminal.
If CI = 20 is specified, the called terminal sends "ALERT (CR # 1 + a)" to VCI = 20 as an ALERT message notifying that the called party is calling. When it detects the caller's off-hook, it sends a CONN message on the same signaling channel.

On the other hand, when the calling terminal receives the CONN message from the called terminal, it sends a response message "CON".
The NACK "message is sent to the point-to-point signal channel VCI = 30 of the destination terminal. The destination terminal monitors the VCI = 30 assigned to itself and monitors the" CONN ACK "from the source terminal. Receive the message.

In this case, the calling terminal hunts the band / VCI management cell, selects an empty VCI of the band / VCI management cell as the point-to-point signal channel of both the calling and destination terminals, and sends the SETUP message. To the destination terminal by adding those VCI numbers. And
Both the originating and terminating terminals exchange call control messages and the like by using these signal channels to realize extension communication.

In the extension call control procedure described above, the bandwidth and the call management can be performed independently, so that the processing such as the bandwidth change can be easily performed. For example, when it is desired to increase the band, the terminal may hunt the band / VCI management cell and change the band value. In addition, since each terminal can know the allocated bandwidth, it is possible to prevent unnecessary calls.

Next, a procedure for setting an outside line call when an incoming call is received from the public network will be described with reference to FIG. In the case of extension communication, since the extension number is used as DA, only one specific terminal returns the ALERT message to the calling side. However, in the case of outside line communication, since the DA may be an address common to the home network, it is conceivable that a plurality of terminals may return the ALERT message. At this time, if a signal channel is assigned to each terminal in advance when the power is turned on (method 1 described above), the point-to-point signal channel assigned to each terminal is used to send the response message to the public. If it is sent back to the network, the switch (L
S) may send the call control message sent to the signaling VCI to the call processor to perform call control.

However, when each terminal hunts the band / VCI cell and acquires the signal channel by the above-mentioned method 2, the switch of the public network manages which channel the call control message is sent to. Can not be.

As a method of solving this problem, the exchange sometimes inquires the home network side of the free VCI,
S terminating the first SETUP message from the switch
There is a method in which when the MT 12 checks the free band of the home network, the free VCI is checked at the same time and the value is notified to the exchange.

Next, in the case described above, that is, SMT
An external call incoming procedure when 12 notifies the exchange of an empty VCI will be described with reference to FIG. The case where the band management cell and the VCI management cell are separately provided will be described below.

Here, it is assumed that the SMT 12 terminates the signal channel of VPI = 0 and VCI = 5 at which the exchange of the public network sends the call control message. SMT12 is VC
When the SETUP message is received on the signal channel of I = 5, the band management cell is hunted in step S41 of FIG. 9, and it is determined in the next step S42 whether or not there is an empty band in the line of the home network.

If it is determined in step S42 that there is a free band, the process proceeds to step S43 to secure a band for outside line,
A value obtained by adding the newly secured band to the used band value (allocated band value) of the band management cell is set in the band management cell as the used band value.

Further, the VCI management cell is hunted in step S44, and the vacant VCI is queried in the next step S45.
It is determined whether or not there is. There is a free band in the determination in step S42, and there is a free VCI in the determination in step S45.
, The SMT 12 notifies the CALL PROC (Call Proc (Call Proc
eeding) "message is sent to a signal channel of VPI = 0 and VCI = 5 that connects the SMT 12 and the public network. At this time, if the empty VCI is VCI = # 20 to 24,
VCI vacant in "CALL PROC" message
"CALL PROC with values added as parameters
(CR # 1 + x, vacant VCI # 20-24) "is sent to the above signal channel.

Further, the SMT 12 sends out a SETUP message to the broadcast type signal channel of the home network. For example, assuming that the broadcast type signal channel is VPI = 0 and VCI = 2, the SMT 12 causes the SETUP message, “SETUP (CR # 0 + a # a + a), which specifies VCI = 20 to 24 as a signal channel that can be used by each terminal. ，
DA, VCI # 20-24) "is sent to VPI = 0 and VCI = 2 of the broadcast signal channel.

On the other hand, if the free band for the outside line does not exist in the determination of the free band in step S42, or if the free VCI does not exist in the determination of the free VCI in step S45, channel release and call number A "REL COM (Release Complete)" message notifying the release is returned to the public network.

Next, in step S46, each terminal monitors the message sent to the broadcast type signal channel, and SE
When the DA of the TUP message matches with its own address, the VCI management cell is hunted to select an empty VCI, that is, one of the VCIs designated by the SETUP message. Then, the terminal sends an ALERT message to the VCI selected by the terminal to inform that it is calling.

For example, the DA of the SETUP message received from the public network coincides with the addresses of the two terminals, and one terminal A receives V as a point-to-point signal channel.
Assuming that CI = 20 is obtained and the other terminal B obtains VCI = 24, each terminal sends an ALERT message informing that it is calling, to each point-point signal channel VCI = 20. And VC
Send to I = 24.

The switch of the public network is notified of the idle VCI of the line of the home network by the "CALL PROC" message sent from the SMT 12.
I is monitored to detect a response message from the destination terminal.

At this time, when the terminal A first detects the off-hook and the CONN message is transmitted to the point-to-point signal channel of the terminal A, VPI = 0, VCI = 20, the public network switch exchanges CONN. When the message is detected, the channel disconnection completion notification REL (Release) “REL (CR # 0 +
a) "is transmitted, and a response message" CONN ACK (CR # 0 + a) "is transmitted to the signal channel VCI = 20 in which the CONN message is detected.

As described above, in response to an incoming call from the outside line, the SMT 12 terminating the signal channel from the public network hunts the band management token and the VCI management token to check the free band and the free VCI value of the home network. , If there is a free band or a free VCI, the information on the VCI is notified to the switch of the public network, so the switch of the public network should recognize which VCI the terminal of the home network responds to. You can

In addition, in the case of an outside line call, each terminal confirms the available band for the outside line, and SETUP is performed only when the available band is available.
Since a message is sent, SE is available even though there is no free bandwidth.
It is possible to prevent useless signal transmission such as transmission of a TUP message.

Next, a communication procedure in the case of a three-way call in which a connection is set up between the calling terminal and a plurality of called terminals will be described with reference to FIG. When the calling terminal notifies the called terminal of the VCI and the called terminal sends a message with the specified VCI, in one-to-one extension communication, only one terminal sends a response message to the calling terminal. There is no problem. However, in one-to-N communication such as three-way communication, a response message is sent from a plurality of destination terminals using a signal channel terminated by the source terminal.
When one message is divided into a plurality of ATM cells and sent, the originating terminal side cannot identify which terminal the received ATM cell belongs to, so the message cannot be reproduced correctly. The problem arises.

In order to solve this problem, in the embodiment described below, a plurality of destination terminals are provided with point-to-point signal channels respectively terminating uniquely, and the calling terminal is used using these point-to-point signal channels. And each destination terminal exchanges a call control message.

In step S51 of FIG. 10, the calling terminal sends a SETUP message, which is a connection setting request message, to the broadcast signal channel. For example, the calling terminal may call identification information “CR # 0 + a” as shown in FIG.
The added “SETUP (CR # 0 + a, DA)” message is added to the VCI = i of VPI = i which is a broadcast type signal channel.
Send to 2.

Each destination terminal takes in the SETUP message sent to the broadcast type signal channel, and the step S52
Compares the destination address DA with the address of the own device.
Then, the terminal having the same address is moved to the next step S5.
In 3, the VCI management cell is taken in and one of the vacant VCIs of the VCI management cell is selected as the point-to-point signal channel at which the own device terminates. Further, in the next step S54, the VCI selected by the VCI management cell is rewritten to assigned.

For example, the terminal A terminates its own device as a point-to-point signal channel with VPI = i VCI.
= 30 is selected, the selected VCI = 30
Is used to send back an ALERT message "ALERT (CR # 1 + a)" notifying that a call is being made.

After that, when the destination terminal A detects the off-hook, it similarly uses the VCI = 30 which is the point-to-point signal channel of its own device to perform "CONN (CR # 1
+ A) "message is sent.

The calling terminal monitors the call control message flowing on SG2 # i (i = 1, 2 ...) Which is a signal channel for call control, and the call with the call identification information sent by itself is added. Detect control messages. When a call control message added with the call identification information transmitted by itself is detected, the signal channel in which the call control message is transmitted is recognized as a point-to-point signal channel terminating at the destination terminal, and the signal is recognized. Send the response message using the channel for communication.

For example, if the calling terminal is V
If an ALERT message and a CONN message are detected on a signaling channel with PI = i and VCI = 30, VC
“CONNACK (CR # 0 + a)” which is a response message of the CONN message is transmitted to the signal channel of I = 30.

Thereafter, the calling terminal and the called terminal A exchange call processing messages by using VCI = 30 of this point-to-point signal channel. On the other hand, the other destination terminal B designated as the destination terminal by the source terminal similarly performs step S
The VCI management cell is hunted at 53, and one of the vacant VCIs of the VCI management cell is selected as a point-to-point signal channel at which the own device terminates. Further, in step S54, the VCI selected by the VCI management cell is rewritten to allocated.

For example, the terminal B terminates its own device as a point-to-point signal channel with VPI = i VCI.
= 40 is selected, the selected VCI = 40
Is used to send back an ALERT message "ALERT (CR # 1 + a)" notifying that a call is being made.

The calling terminal sends SG2 # i in the same manner as described above.
When the call control message flowing above is monitored and the call control message to which the call identification information sent by itself is added is detected, the response message is returned using the signal channel. Thereafter, the calling terminal and the called terminal B exchange call processing messages by using the signaling channel of VCI = 40.

By exchanging the call control message between the calling terminal and the plurality of called terminals according to the procedure described above, a one-to-N call such as a multi-party call can be realized without using the PBX.

In the above embodiment, the case where the destination terminal selects a point-to-point signal channel terminated by the own device and returns a response message using the selected signal channel has been described. Method also 1 to N
Communication can be realized. For example, the calling terminal hunts the VCI management cell to secure VCIs for the number of terminals to which a connection is to be set, and the secured VCIs are added to the connection setting request message to all terminals using the broadcast type signal channel. To broadcast. Then, the destination terminal A, which wants to set a connection with the source terminal, selects one of the VCIs in the connection setting request message, rewrites the selected VCI of the connection setting request message as assigned, and relays it to another terminal. The destination terminal A is the selected VCI.
Send a response message on the signaling channel of. Similarly, the other terminal B also selects one of the empty VCIs in the connection setting request message, rewrites the selected VCI to allocated, relays it to another terminal, and sends a response message on the signal channel of the selected VCI. To do. Also in this case, a 1-to-N call can be realized without using the PBX as in the above-described embodiment.

Further, when the power is turned on or when a terminal is inserted, a meta-signaling procedure is executed to set a point-to-point signal channel in each terminal in advance, and each called terminal which wants to set a connection with the calling terminal It is also possible to send a response message on the point-to-point signal channel set in the own device, and the calling terminal and the called terminal can exchange call processing messages by using these point-to-point signal channels.

In the above embodiment, the case of the one-to-many extension call is explained, but the one-to-N call including the outside call is also included.
Call is also realized by setting signal channels for external lines and communicating using those signal channels in the same way as the external line call setting procedure (see FIG. 9) when there is an incoming call from the public network. it can.

A buffer is provided in the SMT 12 located at the contact point between the public network and the private network, and when ATM cells arrive from the public network and there is no empty cell on the transmission medium of the private network, ATM for extension mutual communication is used. You can also temporarily save cells in the buffer. With such a configuration, cells from the outside line can be preferentially flowed into the internal network, and outside line communication can be given priority at the cell level.

[0086]

According to the present invention, since each terminal device can manage the used band / used VCI of the transmission medium of the home network in a distributed manner, centralized management by PBX or the like becomes unnecessary. In addition, each terminal device can easily change the band by capturing the band management token and updating the used band. Further, by mutually recognizing the signaling channel terminated only by the originating / terminating terminal, or between the terminal and the exchange of the public network, extension / outside communication can be realized without intervening the PBX. In addition, each destination terminal device has a signal channel terminated only by itself, and the calling terminal device and a plurality of destination terminal devices exchange call control messages by using these signal channels. PBX for communication
It can be realized without intervening.

[Brief description of drawings]

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

FIG. 2 is a diagram showing a configuration of a home network of an embodiment.

FIG. 3 is a diagram showing a configuration of an ATM ring.

FIG. 4 is a diagram showing a structure of a band / VCI management token.

FIG. 5 is a flowchart of a call control process performed by a terminal and SMT.

FIG. 6 is a diagram showing an extension call procedure when a calling terminal determines a point-to-point signal VCI shared by both the calling and terminating terminals.

FIG. 7 is a diagram showing an extension call procedure when each of the originating and terminating terminals determines a point-to-point signal VCI.

FIG. 8 is a diagram showing an extension call procedure when the calling terminal determines the point-to-point signal VCI of both the calling and terminating terminals.

FIG. 9 is a diagram showing an external line incoming call procedure.

FIG. 10 is a diagram showing a calling procedure when a connection is set up between a calling terminal and a plurality of called terminals.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Monitoring means 2 Management means 3 Terminal device 4 Terminal management device

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Ichiro Iida 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited (72) Inventor Yoshihiro Watanabe 1015, Kamiodanaka, Nakahara-ku, Kawasaki, Kanagawa Prefecture Fujitsu Limited ( 72) Inventor Kazuo Kano 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa, Fujitsu Limited 1-1-6 Uchisaiwaicho, Chiyoda-ku, Nihon Telegraph and Telephone Corp. (72) Inventor Jun Shinpadi 1-1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corp.

Claims (18)

[Claims] 1. In a home network composed of a plurality of terminal devices sharing a transmission medium, management information storing at least information indicating a free channel of the transmission medium is circulated on the transmission medium, and each terminal device is controlled by call control. A monitoring unit (1) for monitoring a message, and when the monitoring unit (1) detects a connection setting request or a release request for an extension line or an external line, the management information circulating on the transmission medium is fetched and the management information is free. A home communication system comprising: a management unit (2) for setting / releasing an extension / outside signal channel based on information indicating a channel. 2. Management means (2) of the terminal device (3) requesting setting / releasing a connection, wherein the management information comprises a bandwidth management token storing information indicating an allocated bandwidth and a free channel. Captures the band management token circulating on the transmission medium, and if the request of the own terminal device is a connection setting request and the band indicated by the band management token has a free space, the band management token has already been allocated. When a request of the own device is a connection release request, the band to be released is subtracted from the allocated band of the band management token to reduce the band of the transmission medium of the home network in each terminal device. The in-home communication method according to claim 1, wherein the management is distributed. 3. The management information is a VCI management token indicating a virtual channel identifier (VCI) of an allocated virtual channel and a free channel, and the terminal device (3) of the terminal device (3) requesting communication with an extension or an outside line. The management means (2) captures the VCI management token, and the communication request is a connection setting request.
When there is a free VCI in the CI management token, the newly used VCI of the bandwidth management token is changed to allocated, and when the communication request is a connection release request, the VCI released by the VCI management token is made empty. 3. The home communication system according to claim 1, wherein the terminal device is changed and VCIs are distributed and managed. 4. An extension use bandwidth field and a total use bandwidth field of inside / outside lines are provided as a bandwidth display field indicating a bandwidth to which the bandwidth management token has been assigned, and when the extension communication is requested, the value of the extension use bandwidth is a predetermined value. The home communication system according to claim 2, wherein a band for an outside line is secured by accepting an extension communication request within the range. 5. When the extension bandwidth of the bandwidth management token exceeds a predetermined value, the extension communication bandwidth is secured by rejecting the extension communication request even if the total usage bandwidth still has a vacancy for the request. The in-home communication system according to claim 4, wherein 6. A call control message is broadcast to all terminal devices sharing a transmission medium using a broadcast type signal channel, each terminal device terminates the call control message, and the corresponding terminal device returns a response message. In the communication method, the calling terminal device adds the number of the point-point signal channel that is shared and terminated only by the calling and called terminals that communicate, as a parameter of the connection setting request message,
The connection setting request message is broadcast to all terminal devices using a broadcast type signal channel, and the destination terminal device is notified of the point-channel number for point communication to be used in subsequent communication. . 7. A VCI management token storing a virtual channel identifier (VCI) of an allocated virtual channel and a free channel of a transmission medium is circulated on the transmission medium, and the calling terminal device captures the VCI management token. Then, an empty VCI of the VCI management token is shared and terminated by only the originating and terminating terminals, and is secured as the VCI of the point signal channel, and the secured point-the VCI of the point signal channel is set as the connection setting request message. In addition to, broadcast to all terminal devices using the broadcast type signal channel, the destination terminal device to notify the number of the point-point signal channel used in the subsequent communication,
7. The home communication system according to claim 6, wherein both the originating and terminating terminal devices exchange call control messages using a point-to-point signal channel terminated by both terminal devices. 8. A call control message is broadcast to all terminal devices sharing a transmission medium using a broadcast type signaling channel,
In a communication method in which each terminal device terminates its call control message and the corresponding terminal sends back a response message, the calling terminal device determines the number of the point-point signal channel at which only the device terminates itself in the connection setup request message. A parameter that is added as a parameter and broadcasts the connection setting request message to all terminal devices using the broadcast type signal channel, and the destination terminal device terminates only itself-the point signal channel number And the point at which both the originating and terminating terminals terminate by sending back the response message using the point signal channel.
Point The signaling channel is notified by the response of the first message, and after that, both the originating and terminating terminal devices have unique points--
A home communication method characterized by exchanging call control messages using a point signal channel. 9. A VCI management token storing a virtual channel identifier (VCI) of an allocated virtual channel and a free channel of the transmission medium is circulated on the transmission medium, and the calling terminal device captures the VCI management token. Then, the empty VCI of the VCI management token is secured as the VCI of the point-point signal channel where only the own device terminates, and the secured VCI of the point-point signal channel is added as a parameter of the connection setting request message. Broadcast to all terminal devices using a broadcast signal channel, the destination terminal device captures the VCI management token,
The empty VCI of the VCI management token is secured as the VCI of the point-point signal channel where only the own device terminates, the secured VCI of the point-point signal channel is added as a parameter of the response message, and the response message is added. The point-point signal channel which is terminated only by the calling terminal device is used for the return, and the calling and destination terminal devices exchange call control messages by using the point-point signal channel which is unique to each other. 9. The in-home communication system according to claim 8. 10. A call control message is broadcast to all terminal devices sharing a transmission medium using a broadcast type signal channel,
In the communication method in which each terminal device terminates its message and the corresponding terminal sends back a response message, the point at which the calling terminal device terminates only at the calling terminal-point signal channel and the point at which only the destination terminal device terminates- Virtual channel identifier of point signal channel (VC
I-) is added as a parameter of the connection setting request message, and the connection setting request message is sent to all the terminal devices using the broadcast type signal channel, so that the calling terminal device will use the point-to-point thereafter for the destination terminal device. The signaling channel is notified by a connection setup request message, and after that, both the originating and terminating terminal devices have unique points--
A home communication system characterized by exchanging call control messages using a point signal channel. 11. A VCI management token storing a virtual channel identifier (VCI) of an allocated virtual channel and a free channel of the transmission medium is circulated on the transmission medium, and the calling terminal device captures the VCI management token. Then, the empty VCI of the VCI management token is secured as the point where only the own device terminates--the VCI of the point signal channel and the point where only the destination terminal device terminates--the VCI of the point signal channel, and the secured own device And point-of-destination terminal device-By adding the VCI of the point signal channel as a parameter of the connection setting request message and broadcasting to all terminal devices using the broadcast type signal channel, the originating and destination terminal devices are unique The point-to-point signal channel that terminates in the Home communication system of claim 10, wherein the device uses the mutually unique point ─ point signal channel to exchange call control messages. 12. A broadcast control channel is used to broadcast a call control message to all terminal devices sharing a transmission medium,
In a communication system in which each terminal device terminates its call control message and the corresponding terminal returns a response message, a terminal management device located at the contact point between the home network and the public network (4)
Is a free band of the home network and a free virtual channel identifier (V
CI) to the exchange of the public network, and when there is an incoming call from the public network, the vacant VCI notified to the exchange is the point at which the destination terminal device should terminate-the VCI of the point signal channel of the connection setup request message. Broadcast to all terminal devices using a broadcast type signal channel in addition to the parameters, and the destination terminal device uses the point-to-point signal channel designated by the terminal management device (4) A home communication system characterized by transmitting a response message to the exchange. 13. A band / VCI management token storing the allocated band of the transmission medium, the allocated virtual channel and the virtual channel identifier (VCI) of the empty channel is circulated on the transmission medium, and the terminal management device (4) ) Captures the bandwidth / VCI management token and checks the free VCI, notifies the free VCI to the exchange of the public network, and when an incoming call is received from the public network, connects the free VCI notified to the exchange. A point-to-point signal added to the setting request message and broadcast to all terminal devices using a broadcast type signal channel, and the destination terminal device and the exchange of the public network are mutually instructed by the terminal management device (4). 13. The in-home communication system according to claim 12, wherein call control messages are exchanged by using a dedicated channel. 14. A call control message is broadcast to all terminal devices sharing a transmission medium using a broadcast type signaling channel,
In a communication method in which each terminal device terminates its call control message and multiple terminals send back response messages, the calling terminal device sends a connection setup request message with call identification information over all broadcast-type signaling channels. While broadcasting to the terminal device, the signal channel of the transmission medium is monitored to detect a response message addressed to the own device, which is returned from the plurality of destination terminal devices and to which the call identification information is added, A plurality of destination terminal devices attempting to set up a connection secures point-to-point signal channels terminated only by the own device and the originating terminal device, respectively, and uses the secured point-point signal channels. The response message is returned to the calling terminal device, and the calling terminal device and the plurality of destination terminal devices check the point-to-point signal for them. The home network system, characterized in that by using the panel to exchange call control messages. 15. A VCI management token indicating a virtual channel identifier (VCI) of an allocated virtual channel of a transmission medium and a free channel is circulated on the transmission medium to establish a connection with the calling terminal device. Each of the plurality of destination terminal devices captures the VCI management token and secures an empty VCI of the VCI management token as a VCI of a point-to-point signal channel terminated only by the own device and the calling terminal device, 15. The home communication system according to claim 14, wherein the reserved VCI of the VCI management token is changed to allocated, and the response message is returned using the reserved point-to-point signal channel. 16. A call control message is broadcast to all terminal devices sharing a transmission medium using a broadcast type signal channel,
In a communication method in which each terminal device terminates its call control message and multiple terminal devices send back response messages, the calling terminal device secures as many point-to-point signal channels as the number of partner terminal devices to which a connection is to be established. Then
A plurality of point-point signal channel numbers are added to the connection setting request message to broadcast to all terminal devices by using the broadcast type signal channel, and a plurality of connections are set up with the calling terminal device. Each of the destination terminal devices receives the connection setting request message, selects one of the point-to-point signal channel numbers in the connection setting request message, and selects the point-to-point signal selected by the connection setting request message. The channel number is rewritten to assigned, the connection setting request message is relayed to another terminal device, and a response message is returned to the calling terminal device using the selected point-to-point signal channel, The originating terminal device and the plurality of destination terminal devices have their points - the home network system, characterized in that using point signal channel to exchange call control messages. 17. A VCI management token storing a virtual channel identifier (VCI) of an allocated virtual channel and a free channel of the transmission medium is circulated on the transmission medium, and the calling terminal device captures the VCI management token. The VCIs of the point-to-point signal channels corresponding to the number of the other terminal devices for which the connection is to be set up, and the secured VCIs of the point-to-point signal channels
Is added to the connection setting request message and broadcast to all terminal devices using a broadcast type signal channel, and each of the plurality of destination terminal devices that intends to set a connection with the calling terminal device has the connection setting request. Upon receiving the request message, one of the empty VCIs of the point-to-point signal channel in the connection setting request message is selected, and the VCI of the selected point-to-point signal channel of the connection setting request message is already assigned. 17. The rewriting, relaying the connection setting request message to another terminal device, and returning the response message to the calling terminal device using the selected point-to-point signal channel. Home communication method. 18. A call control message is broadcast to all terminal devices sharing a transmission medium using a broadcast type signal channel,
In a communication method in which each terminal device terminates its call control message and a plurality of terminals send back response messages, the calling terminal device broadcasts a connection setting request message to all terminal devices using a broadcast type signal channel, and A plurality of destination terminal devices trying to set up a connection with the source terminal device, return a response message to the source terminal device using a point-point signal channel pre-allocated to the device itself, An in-home communication system, wherein a calling terminal device and the plurality of destination terminal devices exchange call control messages using their point-to-point signal channels.