JPH04351055A - Isdn number converter - Google Patents

Abstract

PURPOSE:To attain the connection of a data terminal equipment having been connected to a DDX-C to an ISDN without revision of a program of a numbering plan by providing a function converting a numbering plan of the DDX-C into a registered numbering plan of the ISDN to a terminal adaptor. CONSTITUTION:Upon the receipt of a dial request from a data terminal equipment, a number storage section 15 checks the presence of registration of a received DDX-C opposite number and converts the number into an ISDN opposite party when being registered and stops dialing when not registered, and the number storage section 15 checks the presence of the registration of the ISDN opposite number when a call comes from the ISDN and rejects the arrival of a call when not registered. The incoming call is informed to the data terminal equipment when registered, the ISDN opposite number is converted into a DDX-C opposite number and the result is informed to the data terminal equipment, then it is not required to revise the program relating to the numbering plan of the data terminal equipment even when the accommodated network is changed from the DDX-C into the ISDN.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention provides data terminal equipment connected to a digital data circuit switching network (hereinafter referred to as DDX-C) to an integrated service digital network (hereinafter referred to as IDX-C).
This invention relates to an ISDN number conversion device used for number conversion when connecting to an ISDN (hereinafter referred to as SDN).

0002

2. Description of the Related Art Conventionally, an example of a case where the procedure for making and receiving calls between a terminal adapter and a data terminal device is performed using the X21 protocol (hereinafter simply abbreviated as X21) recommended by the CCITT is taken as an example. Figure 16 shows the sequence between ISDNs.
, will be explained with reference to FIG.

FIG. 16 shows a transmission sequence. When the data terminal device issues a call request and receives a selection signal transmission permission response, it transmits a selection signal, that is, connection destination information. The terminal adapter incorporates the received selection signal into the called party number of the call setup message as the ISDN connection destination, and
Send to SDN.

[0004] When the ISDN receives the call setup message, it sends out a call setup acceptance message, and if the called party specified by the called number responds, it sends out a response message.

[0005] When the terminal adapter receives the response message, it sends a connection completion and communication permission message to the data terminal device, and starts communication.

FIG. 17 shows an incoming call sequence. This figure 1
At step 7, upon receiving the call setup message from the ISDN, the terminal adapter sends a call setup acceptance message and sends out the incoming call to the data terminal device.

[0007] When the terminal adapter receives an incoming call acceptance from the data terminal device, it sends a response message to the ISDN, and
When the terminal adapter receives a corresponding response confirmation message from the ISDN, the terminal adapter sends the calling number included in the call setup message to the data terminal equipment as a destination number notification.

[0008] Thereafter, the terminal adapter sends a connection completion and communication enable message to the data terminal device, and starts communication.

As described above, the conventional terminal adapter creates the called number of the call setup message from the selection signal, and also creates the destination number notification from the calling number of the call setup message.

0010

[Problems to be Solved by the Invention] However, in the above-mentioned conventional call/receive procedure between the terminal adapter and the data terminal device, the data terminal device connected to the DDX-C is connected to the ISDN.
In order to connect to the Internet, the number plan increases from 7 digits for DDX-C to 10 digits for ISDN, so it is necessary to change the program related to the numbering plan of the data terminal device, and the amount of change is large. was the problem.

The present invention solves these conventional problems and provides an excellent ISDN number conversion device that can replace the accommodation network without changing the program of the data terminal device. It is to be.

0012

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a setting in which a terminal adapter is made to correspond to a partner subscription number in connection destination information in DDX-C and a called party number in connection destination information in ISDN. The reception selection signal from the data terminal device is checked against the set subscriber number of the other party, and if they match, a call setup message is created and sent using the corresponding called party number. The subscriber number of the other party in the information and the called party number of the connection destination information in ISDN are stored in correspondence, and the reception selection signal from the data terminal equipment is compared with the subscriber number of the other party stored in the number storage section, and if they match, a call is made to ISDN. and in case of discrepancy,
Sends a call failure to the data terminal equipment, and when a call arrives from ISDN, if the calling number in the call setup message and the called number in the number storage match, output the other party's number to the data terminal equipment; , so that it does not respond to incoming calls.

[0013]

[Operation] Therefore, according to the present invention, when the reception selection signals from the data terminal equipment match, a call setup message is created and sent based on the called party number, so that the reception selection signal from the data terminal equipment and the other party's connection can be exchanged. If the subscriber numbers match, the call is made to the ISDN, and when the calling party number in the call setup message matches the pre-stored called party number when the call is received from the ISDN, the receiving party number is output to the data terminal equipment. Even when the network is changed from DDX-C to ISDN, there is an advantage that there is no need to change the numbering plan of the communication partner of the data terminal device.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the internal structure of a terminal adapter according to the present invention. For convenience of explanation, FIG. 1 will be described later, and the explanation will proceed from FIG. 2. This figure 2
1 shows the system configuration of the first embodiment of the present invention. In FIG. 2, 1 and 4 are data terminals (hereinafter referred to as DTE), and 2 and 5 are terminal adapters, respectively. Terminal adapters 2 and 5 are connected between DTEs 1 and 4, respectively, and network-side home line termination units 6 and 7 (hereinafter referred to as DSU). 3 is ISDN.

That is, DTEs 1 and 4 are connected to ISDN 3 through terminal adapters 2 and 5 and DSUs 6 and 7, respectively.

Next, the operation of the first embodiment will be explained. FIG. 3 shows a sequence when transmitting X21, which is a connection control procedure between the terminal adapter 2 and the DTE 1. The circuit T in FIG. 3(a) shows the transmission data going from the DTE1 to the terminal adapter 2, and the circuit C in FIG.
is a control signal from DT to terminal adapter 2.
This is a signal line for controlling the terminal adapter 2 from E1. Circuit R in FIG. 3(c) is from terminal adapter 2 to DTE1.
Figure 3 (
The circuit I in d) is an indication signal from the terminal adapter 2 to the DTE1, and is a signal line for controlling the DTE1.

Here, regarding the operation when the DTE 1 makes a transmission, the circuit T in FIG. 3(a) is changed from 1 to 0, and the circuit shown in FIG.
Turn on circuit C from off to on in b), issue a call request from DTE 1 to terminal adapter 2, and terminal adapter 2 that received this call request transmits the SYN of two synchronization characters to circuit R in FIG. 3(c). Sign and plus sign (+) are sent, and D
Notify TE1 that selection signal transmission is possible.

After receiving the selection signal transmission enable signal, the DTE 1 attaches two or more SYN codes to the circuit T shown in FIG. 3(a) and transmits the selection signal to the terminal adapter 2. The format of this selection signal is shown in FIG. The partner number here, that is, the connection destination information, is a 7-digit number according to the DDX-C numbering plan.

When the terminal adapter 2 receives the + sign (see FIG. 4) indicating the end of the selection signal, it stops transmitting the + sign from the circuit R shown in FIG. 3(c) and transmits the SYN code.

The terminal adapter 2 checks whether the received partner's subscription number is registered in the number conversion memory.

As a result of this verification, if it is determined that the partner's subscription number received by the terminal adapter 2 is not registered in the number conversion memory, if the partner's subscription number is not registered in the number conversion memory, the 5 is applied, and two SYNs are applied to circuit R shown in Fig. 5(c).
A call progress signal preceded by a code is sent from the terminal adapter 2 to the DTE 1.

In FIG. 5, FIG. 5(a) shows the circuit T,
5(b) shows circuit C, FIG. 5(d) shows circuit I, and FIG.
The format of the call progress signal of circuit R in (c) is shown in FIG. “△△” in FIG. 6 is a reason code.

After transmitting the call progress signal, in step 108, the ID signal of circuit R in FIG. 5(c) is transmitted,
Thereafter, the circuit R is set to 0, and the procedure for instructing disconnection is taken.

[0024] Furthermore, if the other party's subscription number received by the terminal adapter 2 is registered in the number conversion memory,
Extract the ISDN partner subscription number that corresponds to the registration number,
It is incorporated into a call setup message as the called number and sent from the terminal adapter 2 to the ISDN 3.

FIG. 7 shows the structure of the call setup message, FIG. 8 shows the information elements of the called number, and FIG. 9 shows the information elements of the calling number. The called number in FIGS. 7 to 9 is the called party's subscription number, and the calling number is the calling party's subscription number.

When the ISDN 3 receives the call setup acceptance message, it returns the call setup acceptance message, and if the other party's terminal responds to the incoming call, it sends out a response message.

When the terminal adapter receives this response message, confirms the response, and completes the preparation for data communication, it stops the SYN code that was being sent to circuit R in FIG. The connection is completed, the circuit I in FIG. 3(d) is turned on from off, and the DTE 1 is notified that communication is possible. This starts data communication.

Next, the operation at the time of receiving a call will be explained. FIG. 10 shows the sequence of the X21 procedure when receiving a call. Figure 10
(a) is circuit T, FIG. 10(b) is circuit C, FIG. 10(c)
shows circuit R, FIG. 10(d) shows circuit I, and FIG.
This is the format of the ID signal of 0(c).

Next, the operation at the time of receiving a call will be explained. When the terminal adapter 5 receives the call setup message from the ISDN 3, the terminal adapter 5 transmits a call setup acceptance message to the ISDN 3 in response.

ISDN 3 extracts the calling number from the call setup message and checks in step 204 whether it is registered as an ISDN partner number. As a result of this verification, if it is determined that it is not registered, the terminal adapter 5 sends a disconnection message to the ISDN 3.

[0031] Furthermore, if it is determined that there is a registration number as a result of the above judgment, the DD corresponding to the ISDN partner number
Take out the contact number of X-C. That is, DDX
-Convert to the other party's subscription number of C.

Next, the terminal adapter 5 is installed as shown in FIG. 10(c).
A BEL code preceded by two SYN codes is transmitted to circuit R of , and the DTE 4 is notified of the incoming call. In response to this incoming call, the DTE 4 turns on the circuit C shown in FIG. 10(b) from OFF to ON and notifies the terminal adapter 5 that the incoming call has been accepted, and the terminal adapter 5 sends a response message to the ISDN 3. .

Next, when the terminal adapter 5 receives a response confirmation message from the ISDN 3, the terminal adapter 5 notifies the DTE 4 of the other party's number as an ID signal. The partner number here is the partner number of the DDX-C that was taken out earlier, and this ID signal is shown in Figure 1.
2(c), it is sent to circuit R in advance of the two SYN signals.

After sending this ID signal, the SYN code sent to circuit R is held at 1 to complete the connection and preparation for data communication is completed, as shown in FIG. 10(d).
Turn on circuit I and enable communication from terminal adapter 5 to DT.
Notify E4. This starts data communication. The above is the operation of the terminal adapter as a system.

Next, the number conversion of the terminal adapter, which is a feature of the present invention, will be explained. Figure 1 shows the ISD of this invention.
It shows the internal configuration of the terminal adapter in the N number conversion device. In FIG. 1, 11 is a DTE/IF which is an interface unit with the DTE, 12 is a data transmission/reception unit that supports the X21 procedure, 13 is a call control unit that supports ISDN communication procedures, and 14 is an ISDN interface unit. This is the ISDN I/F.

Reference numeral 15 denotes a number storage unit that converts and stores numbers newly established for this invention, and 16 stores in this number storage unit 15 the partner subscriber number of connection destination information in DDX-C and connection destination information in ISDN. This is a panel section for sending predetermined input by operating a keyboard (not shown) or the like in order to make settings corresponding to the numbers.

Next, the operation will be explained. First, registration of conversion numbers will be explained. Conversion number number storage section 15
The settings are registered by operating the panel section 16. Setting command, DDX-C partner number, ISDN on the panel
Enter the other party's subscription number in order. The panel unit 16 sends the input number to the number storage unit 15.

The number storage section 15 stores the number sent from the panel section 16 in the memory in the structure shown in FIG. The setting address represents the number of the storage number, the DDX-C partner's subscription number is the partner's number in the DDX-C numbering plan, the content length indicates the number of digits of the ISDN partner's subscription number, and the ISDN partner's subscription number is the ISDN partner's subscription number. Indicates the other party's number in the numbering plan.

Next, number conversion at the time of a call will be explained with reference to the flowchart of FIG. 13. D in step 101
The TE issues a call request (FIG. 14(b)) to the terminal adapter, and the terminal adapter that receives this call request performs step 10.
In step 2, the DTE is notified that the selection signal can be sent (FIG. 14(a)).

After the DTE receives the selection signal transmission permission, in step 103 the DTE transmits a selection signal to the terminal adapter. When this selection signal is received by the data transmitting/receiving section 12, only the partner number is extracted from the selection signal and delivered to the number storage section 15 in step 104.

[0041] As a result, the number storage section 15 performs step 1.
DDX with the other party's number received in 05 stored in memory
-Verify with C's partner number. As a result of this verification, if it is determined that the number is not registered (step 106), the number storage unit 15 informs the data transmitting/receiving unit 12 of the missing number, and in step 107, the call progress signal (FIG. 14(c)) is sent to D.
Send to TE.

After sending this call progress signal, an ID signal is sent in step 108, and then step 10
When a disconnection instruction is sent in step 9 and a disconnection confirmation is received in step 110, DCE (data circular) is sent in step 111.
cuit terminating equipment
t) Ready, step 112 DTE (data
rminal equipment) After taking the ready procedure, the data transmitting/receiving section 12 goes to the outgoing call termination sequence and enters a standby state.

Further, in step 106, if the partner number extracted from the selection signal is stored in the memory of the number storage unit 15, the process proceeds from the NO side of step 106 to step 113, and in this step 113, the number corresponding to the registered number is stored in the memory of the number storage unit 15. The ISDN partner subscription number is retrieved from the memory and sent to the call control unit 13 along with the call request. The call control unit 13 sets the received ISDN partner number as the number digits of the called number in the call setup message, sets its own ISDN subscription number as the number digits of the calling number, and sends the message to the ISDN. (Figure 14(d)).

In response to the call setting received in step 114, the ISDN returns a call setting acceptance message in step 115, and if the other party terminal responds to the incoming call, in step 116,
Send a response message.

[0045] The terminal adapter receives this response message, transmits a response confirmation in step 117, and completes preparations for data communication. In step 118, the terminal adapter notifies the DTE that the connection is complete, and in step 119, that communication is possible. According to
Communication begins.

Next, regarding number conversion at the time of incoming call, FIG.
This will be explained according to the flowchart. When a call setup is received in step 201, a call setup acceptance is sent in step 202, and the call control unit 13 extracts the number digits of the calling number from the call setup message received from the ISDN, and passes it to the number storage unit 15 in step 204. .

The number storage unit 15 checks whether the number received from the call control unit 13 is registered in the memory as an ISDN partner number, and if it is not registered as a result of the checking, the YES side of step 205 is returned. From step 20
6, the number storage unit 15 notifies the call control unit 13 of the calling number mismatch. As a result, the call control unit 13
By transmitting a disconnection message to , receiving a release in step 207, and completing the release in step 208, the incoming call is rejected and the data transmitting/receiving unit 12 is not notified of the incoming call, and enters a standby state.

Furthermore, as a result of the determination in step 206, I
If the SDN partner number is registered, the process proceeds from the NO side of step 206 to step 209, where the DDX-C partner subscription number corresponding to the ISDN partner number is retrieved, and transmitted to the data transmitting/receiving unit 12 along with the incoming call notification in step 210. .

[0049] After receiving the incoming call acceptance, the data transmitting/receiving unit 12
After responding in step 212 and confirming the response in step 213, in step 214 the DDX-C partner's subscription number is sent to the DTE.
, complete the connection in step 215, and proceed to step 2.
At 16, communication is enabled and the communication state is established.

As described above, according to the first embodiment, the terminal adapter is configured to correspond to the partner subscription number in the connection destination information in DDX-C and the called party number in the connection information in ISDN, and The selection signal is checked against the set subscriber number, and if they match, a call setup message is created and sent using the corresponding called party number, making it possible to rewrite the accommodating network without changing the program of the data terminal equipment. This has the effect of making it possible.

[0051]

Effects of the Invention As is clear from the embodiments described above, the present invention sets the terminal adapter so that the other party's subscription number in the connection destination information in DDX-C corresponds to the called party number in the connection destination information in ISDN. The selection signal from the device is checked against the set subscriber number of the other party, and if they match, a call setup message is created and sent using the corresponding called party number, and the accommodation network is changed from DDX-C to ISDN. Even when changed, there is an effect that there is no need to change the numbering plan of the communication partner of the DTE.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a terminal adapter in an ISDN number conversion device in a first embodiment of the present invention.

FIG. 2 is a system configuration diagram of an ISDN number conversion device in the first embodiment of the present invention.

FIG. 3 is an X21 calling sequence diagram for explaining the calling sequence of the ISDN number converter in FIG. 2;

FIG. 4 is an explanatory diagram showing a signal format of a selection signal shown in FIG. 3;

FIG. 5 is an X21 call cancellation sequence diagram for explaining the sequence when the ISDN number conversion device shown in FIG. 2 cancels a call;

FIG. 6 is an explanatory diagram showing a signal format of a call progress signal shown in FIG. 5;

FIG. 7 is an explanatory diagram showing the structure of a call setup message applied to a second ISDN number conversion device.

FIG. 8 is an explanatory diagram showing the configuration of information elements of a called number applied to the second ISDN number conversion device.

FIG. 9 is an explanatory diagram showing the configuration of information elements of a calling number applied to the ISDN number conversion device of FIG. 2;

FIG. 10 is an X21 call reception sequence diagram for explaining the sequence when the ISDN number conversion device of FIG. 2 receives a call;

FIG. 11 is an explanatory diagram showing the signal format of the ID signal shown in FIG. 10;

FIG. 12 is an explanatory diagram of a method of storing a conversion number stored in the memory of the number storage unit in the terminal adapter of FIG. 2;

FIG. 13 is a flowchart showing the operation flow of the terminal adapter in FIG. 2 when making a call;

[Figure 14] DTE and ISDN of the terminal adapter in Figure 2
An explanatory diagram of a message to.

FIG. 15 is a flowchart showing the operation flow of the terminal adapter in FIG. 2 when receiving a call.

FIG. 16 is a diagram of a transmission sequence between a conventional terminal adapter and a data terminal device.

FIG. 17 is an incoming call sequence diagram between a conventional terminal adapter and a data terminal device.

[Explanation of symbols]

1, 4 DTE 2, 5 Terminal adapter 3 ISDN 6, 7 DSU 11 DTE I/F 12 Data transmission/reception section 13 Call control unit 14 ISDN I/F 15 Number storage section 16 Panel part

Claims (1)

[Claims] Claim 1: Provided in a terminal adapter for connecting a data terminal device connected to a digital data circuit switching network to an integrated service digital network, a terminal adapter that includes connection destination information in the digital data circuit switching network. a number storage unit that is set in correspondence with the subscriber number of the other party and the called party number of the connection destination information in the integrated service digital network, and that verifies the connection destination information from the data terminal device and the set contents; and a call control unit that converts connection destination information from the data terminal device into connection destination information of the integrated service digital network and makes a call if the two match as a result of the comparison of the number storage unit. Number conversion device.