JPH1132118A - Cug call control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the method where even a terminal not supporting a specific communication procedure belongs to plural closed user groups(CUG). SOLUTION: In the case that an exchange 20 receives a call request message 1 not including a CUG index that denotes a CUG to which a called terminal 40 belongs from a caller terminal 10, a CUG interlock code registered in advance with respect to an incoming call number included in a call request message 1 is acquired, the CUG interlock code is used to start a CUG call designating the CUG to which the called terminal 40 belongs explicitly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CUG call control method, and more particularly, to a CU for each destination number in an originating exchange.
The present invention relates to a CUG call control method for selecting G and automatically starting a CUG call.

[0002]

2. Description of the Related Art CUG (Closed Use) in an ISDN network
r Group) service is a closed connection service that enables a plurality of terminals to form a group according to the recommendation of ITU-T0955.1, and restricts access to the group or communication from the group. . According to this service, a certain terminal can be a member of a plurality of CUGs, and a member of a certain CUG can communicate between members in the group, but generally cannot communicate with terminals outside the group. .

As a method of transmitting a CUG call, a facility information element at the time of a call request includes a CUG index for designating a CUG call and specifying a CUG to be used.
And a default request to activate the priority CUG without including the facility information element at the time of a call request. The priority CUG is the CU at the time of calling request.
This is a CUG that is automatically activated when no G information is included, and only one CUG can be set in advance for one subscriber.

FIG. 5 is a sequence diagram when a CUG call is originated by an explicit request. Upon receiving the call request by the explicit request, the calling exchange 65 checks whether the calling terminal 60 has subscribed to the CUG service and whether or not it belongs to the designated CUG. Upon receiving the call request by the default request, the originating exchange (not shown) checks whether the caller has subscribed to the CUG service and whether the priority CUG is set in advance.

[0005] These checks in the originating exchange are referred to as C
This is called a UG originating side check (67 in FIG. 5). When the CUG originating side check is completed normally, the designated CUG or priority CUG is converted into an interlock code, and is added to a call request message to the destination exchange 66 and transmitted.

[0006] The interlock code is C
A CUG index is a value used to identify a CUG by a user, whereas a CUG index is a value used to identify a CUG. May be different. The destination exchange 66 uses the received interlock code to check whether the called party belongs to the CUG. This is CU
This is referred to as a G-side check (68 in FIG. 5).

When the check is completed normally, the interlock code is converted into the CUG index of the called party (69 in FIG. 5), set in the facility information element, and a call request is sent to the called party. On the other hand, if either the outgoing side check or the incoming side check becomes abnormal, the call is released.

FIG. 6 is an explanatory diagram showing calling of terminals belonging to two different CUGs. In FIG.
The terminal 61 belongs to the CUG-A 63 and the terminal 62 belongs to the CU-A 63 and the CUG-B 64.
Belongs to GB-B64. Also, the priority CUG of the terminal 60
Is set in advance as CUG-B64.

The terminal 60 can receive an incoming call if the terminal 61 calls the terminal 61 by designating the CUG-A 63 by an explicit request. Also for terminal 62, C
If you specify UG-B64, you can receive a call. However, the terminal 60 can only receive a call to the terminal 62 because the CUG-B 64 that is the priority CUG is automatically activated by the default request.

If a call is made to the terminal 61 by a default request, the result of the check on the called side becomes abnormal and the call cannot be received. That is, in the conventional method, if the CUG is not specified in the call request, one preset CUG is automatically activated regardless of the destination.

[0011]

Therefore, according to such a conventional CUG call control method, the CUG cannot be designated unless the originating terminal has a specific communication procedure. There was a problem that the sex was uneven. This is because, in the CUG service in the lSDN network, a specific CUG can be specified by the facility information element used in the circuit call connection means, but the terminal that cannot send out the facility information element is a CUG service.
This is because the UG cannot be specified, so that only the priority CUG can be used and cannot belong to a plurality of CUGs.

[0012] Further, since the CUG service is a service that allows communication between members of the CUG, even if a caller designates a specific CUG at the originating exchange or is permitted using the priority CUG, In some cases, the incoming call is not allowed in the incoming call check at the incoming exchange, and in this case, the line call connection is released according to the instruction of the incoming exchange, and the communication line between the originating exchange and the incoming exchange is wasted. However, there is a problem of inefficiency because an incomplete call is generated.

This is because it cannot be determined whether or not the called party belongs to the CUG specified by the calling party or the activated priority CUG until a CUG called side check is performed in the called side exchange. The present invention has been made to solve such a problem, and has as its object to provide a CUG call control method for automatically selecting and activating a CUG according to a called number.

[0014]

In order to achieve the above object, a CUG call control method according to the present invention provides a call request message which does not include a CUG index indicating a CUG to which a terminating terminal belongs in an exchange. When the call is received from the calling terminal, a CUG interlock code registered in advance for the called number included in the call request message is acquired, and the CUG to which the called terminal belongs is obtained using the CUG interlock code. Is activated to explicitly activate the CUG call. Therefore, when a call request message that does not include the CUG index indicating the CUG to which the called terminal belongs is received, the CUG interlock code corresponding to the called number included in the call request message is used. CU to which the CUG to which the called terminal belongs is explicitly specified
The G call is activated.

[0015] When the receiving terminal is accommodated in its own station, the CUG interlock code is assigned to the corresponding CUG interlock code.
The CUG call is activated by transmitting a call setting message, which is converted into an index and to which the obtained CUG index is added, to the receiving terminal. If the receiving terminal is not accommodated in its own station, the CU
The CUG call is activated by transmitting a call setup message to which the G interlock code is added to the destination exchange in which the receiving terminal is accommodated.

[0016]

Next, the present invention will be described with reference to the drawings. FIG. 1 shows a CU according to an embodiment of the present invention.
It is a block diagram of the exchange system by the G call control method. In FIG. 1, the exchange 20 includes a signal processing unit 21 for transmitting and receiving signals, a call processing control unit 22 for checking the normality of a call, and a subscriber data storage unit for storing correspondence between a called number and a CUG for each subscriber. 25.

The call processing control section 22 has an outgoing connection processing section 23 for performing connection processing of a calling terminal, and an incoming connection processing section 24 for performing connection processing of a called terminal. The originating terminal 10 is accommodated in the exchange 20, and the terminating terminal 40 is accommodated in the exchange 30. The exchange 20 and the exchange 30 are connected by a common signal line (lSUP).

FIG. 2 is an explanatory diagram showing a conversion table for selecting a CUG to be used from a called number. Originating exchange 2
The conversion table is registered in advance in the 0 subscriber data storage unit 25 for each subscriber. The transmitting terminal 10 is the receiving terminal 4
In the case of communication with the exchange 20, the SETUP message 1 is transmitted to the exchange 20 as a call request message not including the CUG information. In the exchange 20, the SETUP message 1 is received by the signal processing unit 21, and a notification 3 is sent to the outgoing connection processing unit 23 in the call processing control unit 22.

The outgoing connection processing unit 23 confirms that the SETUP message 1 from the outgoing terminal 10 does not include the CUG information, delivers the called number “1234567” 4 to the subscriber data storage unit 25, and uses it. CU to be
Request G. The subscriber data storage unit 25 searches the conversion table (FIG. 2) based on the caller information, and retrieves the interlock code (I
LK) Acquire “ABCD0000” and call processing control unit 2
The result 5 is returned to the outgoing connection processing unit 23 in 2.

The outgoing connection processing unit 23 receives the original SE
The TUP message 1 contains the interlock code "ABCD
0000 ”, and as if the calling terminal 10
After the G call is requested and the result of the calling side check is set as normal, the incoming call processing unit 24 is requested to perform a connection process to the incoming terminal. In response, the incoming connection processing unit 24 determines whether the incoming terminal 40 is accommodated in the exchange 30 of another station.

Here, the receiving terminal is connected to another station, for example, exchange 3
If it is confirmed that the message is accommodated in “0”, the request 6 is sent to the signal processing unit 21 to send a message to the receiving terminal 40. In response, the signal processing unit 21 sends the CUG interlock code “AB” to the exchange 30.
An IAM message 8 to which "CD0000" is added is transmitted.

In the exchange 30, a normal CUG receiving side check is performed, but since the result always becomes normal, the interlock code is stored in the CUG index (C
UGindex) and indexed S
An ETUP message 9 is sent to the receiving terminal 40. As a result, a CUG call is established.

When the receiving terminal is accommodated in the exchange 20 of its own station, a normal CUG arrival is performed by using a new message in which the interlock code "ABCD0000" is added to the received original SETUP message 1. Perform a side check. Also in this case, since the result always becomes normal, the interlock code is converted into the CUG index (CUG index) of the receiving terminal, and the SETUP message 9 to which the index is added is transmitted to the receiving terminal. As a result, a CUG call is established.

Next, the processing operation of the present invention will be described with reference to FIGS. FIG. 3 is a sequence diagram showing a processing operation example of the present invention, and FIG. 4 is a flowchart showing an operation procedure in the originating exchange. First, by transmitting a SETUP message 31 from the transmitting terminal 10 to the receiving terminal 40, a call is transmitted as a normal line connection.

The exchange 20 that has received the SETUP message 31 starts the processing shown in FIG. First, after checking that CUG information is not included in the received SETUP message (step 41: NO) and that the calling terminal is a subscriber of the CUG service (step 42: YES), the CUG conversion table is set in advance. It is checked whether or not it has been registered (step 43).

If registered (step 43: YES), an interlock code to be used is searched based on the called number in the SETUP message (step 44). Then, in response to the successful search of the corresponding interlock code (step 45: YES), the interlock code is set in the IAM message 8 to the destination exchange as if the CUG was requested by the calling terminal.

Since the searched interlock code is a CUG that can be reliably received by the destination terminal 40, the result of the CUG destination check at the destination exchange becomes normal, and the CUG index of the destination terminal 40 is Converted, a SETUP message is sent, and a CUG call is established (step 46). If the CUG information is included (step 41: YES), a CUG calling side check is performed (step 47), and the process ends.

If the calling terminal is not a subscriber of the CUG service (step 42: NO), if the conversion table is not registered (step 43: NO), the corresponding interlock code cannot be searched from the conversion table. In either case (step 45: NO), a CUG calling side check is performed (step 47),
The process ends.

Thus, in the exchange 20, C
An IAM message 8 to which the UG interlock code “ABCD0000” is added is generated and sent to the exchange 30. On the other hand, in the exchange 30, a normal CUG receiving side check is performed, but since the result is always normal, the interlock code is converted into the CUG index (CUG index) of the receiving terminal 40, and the SETUP message 9 to which the index is added is converted. It is sent to the receiving terminal 40, and a CUG call is established.

[0030]

As described above, according to the present invention, a communicable CUG is registered in the exchange in advance for each called number.
When a call request message that does not include the CUG index is received, a CUG interlock code to be used is searched for from the calling number and the called number in the message, and the CU is automatically used using the searched CUG interlock code.
Since the G call is activated, a terminal that does not support a specific communication procedure can belong to a plurality of CUGs, and the applicability of the service is improved. Also,
Since the exchange automatically selects the CUG that can reliably communicate,
In the CUG destination side check in the destination side exchange, it always becomes normal and communication becomes possible, and occurrence of an incomplete call can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of an exchange system according to a CUG call control method according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a conversion table for selecting a CUG from a called number.

FIG. 3 is a sequence diagram illustrating a processing operation example of the present invention.

FIG. 4 is a flowchart showing an operation procedure in an originating exchange.

FIG. 5 is a sequence diagram showing a processing operation when a CUG call is originated by an explicit request.

FIG. 6 is an explanatory diagram showing calling of a terminal belonging to two different CUGs.

[Explanation of symbols]

10 originating terminal, 20 originating exchange, 21 signal processing unit, 22 call processing control unit, 23 originating connection processing unit, 24
... incoming connection processing unit, 25 ... subscriber data storage unit, 30 ...
Incoming exchange, 40 ... Receiving terminal.

Claims (3)

[Claims] 1. A CUG call control method for starting a CUG call from an exchange to an incoming terminal belonging to a preset CUG in response to an outgoing call request message from an originating terminal. When a call request message not including the CUG index indicating the CUG to which the call request belongs is received from the calling terminal, a CUG interlock code registered in advance for the called number included in the call request message A CUG call control method comprising: starting a CUG call in which a CUG to which a terminating terminal belongs is explicitly specified by using the CUG interlock code. 2. The CUG control method according to claim 1, wherein when the receiving terminal is accommodated in the own station, the CUG interlock code is converted into a corresponding CUG index, and the obtained CUG index is added. A CUG call control method characterized by initiating a CUG call by transmitting a call setup message to a receiving terminal. 3. The CUG control method according to claim 1, wherein, when the receiving terminal is not accommodated in the own station, the call setting message added with the CUG interlock code is transmitted to the receiving side in which the receiving terminal is accommodated. A CUG call control method characterized by initiating a CUG call by transmitting it to an exchange.