JPH0549077A - R point clock automatic changeover system - Google Patents

Abstract

PURPOSE:To automatically set an R point clock suitable for an ISDN communication system. CONSTITUTION:In order to make communication among plural ISDNs whose communication speed differs from each other, a composite ISDN having an ISDN terminal equipment varying an R point clock of an R point clock output circuit 1 is featured to be provided with an R point clock speed identification information input means 2 receiving R point clock speed identification information together with path setting information to an incoming call destination in the case of dialing, or an extract means extracting user speed information in a call setup message received in the case of the arrival of an incoming call, a clock revision control means 3 outputting revision information in response to the R point clock speed identification information or the user speed information and an R point clock revision means 4 revising an R point clock in response to the revision information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to ISDs for use.
The present invention relates to an R point clock automatic switching method for automatically switching an R point clock using switching control information without taking an R point clock setting processing sequence via an N communication system.

ISDN (Integrated Service Digital N)
There is a case in which a plurality of ISDN exchanges having different communication speeds are interposed between the data terminal devices to set a single ISDN communication system in order to perform desired communication. Even in such a composite ISDN, a means capable of achieving normal communication has been conventionally adopted.

[0003]

2. Description of the Related Art FIG. 6 shows an example of forming the above-mentioned composite ISDN. 50 and 51 are circuit switching networks (I
SDN switching network), 52 is a circuit switching network (ISDN switching network) having a communication speed of 56 Kbps, 53, 54 and 55 are ISDN terminal devices, 56 is a data terminal device connected to the ISDN terminal device 53, and 57 is an ISDN terminal device 54. And 58 is a data terminal device connected to the ISDN terminal device 55. FIG. 7 shows a configuration diagram of an ISDN terminal device. In FIG. 7, 30 is an ISDN line interface circuit, 31 is a bus, 32 is a microprocessor, 33 is a memory, 34 and 35 are R point interface circuits, 36 is a key and LED, and 37 and 38 are data terminal devices. Each of the R-point interface circuits 34 and 35 has an R-point clock generation circuit, and each of the R-point clock generation circuits is configured so that the clock cycle can be changed.

A frame format transmitted from the ISDN terminal device 53 to the circuit switching network 50 when a data terminal device having a communication speed of 56 Kbps is connected to the ISDN terminal device 53 in the circuit switching network 50 having a communication speed of 64 Kbps. Is shown in Fig. 8 and the communication speed is 64Kb.
Communication speed of 48Kbps or 64Kb on ps circuit switching network 50
9 and 10 show the frame formats transmitted from the ISDN terminal device 53 to the circuit switching network 50 when the ps data terminal device is connected to the ISDN terminal device 53. These frame formats are the frame formats shown in V.110 of CCITT Recommendation.

Since such a frame format configuration is adopted, 64 is used in ISDN as described above.
6 Kbps data terminal device via ISDN terminal device 53
64Kb when connected to a 4Kbps circuit switching network
In communication from the ps circuit-switched network to the 56 Kbps circuit-switched network, data bits are inserted in the bit number 8 of the frame format and the frame format (see FIG. 1).
No. 0) is configured, the data bits are missing (see the shaded area in FIG. 10), which hinders communication between them.

In addition, 64 Kb in the above ISDN
56Kbps data terminal equipment is IS on the ps circuit switching network 50.
When the connection is made via the DN terminal device 53, even if the dummy bit “1” (see the hatching in FIG. 8) inserted in the bit number 8 is missing, the communication between the two is disturbed. Does not come. Similarly, the above 6 in ISDN
When a 48 Kbps data terminal device is connected to a 4 Kbps circuit switching network 50 via an ISDN terminal device 53,
The frame format as shown in (1) is transmitted from the circuit switching network 50 of 64 Kbps to the circuit switching network 52 of 56 Kbps. In the 56 Kbps circuit switching network 52, the control bit of the bit number 8 in the frame format is set at the time of the call setting. This is also 6 because we have the recognition that it will not be sent.
4 Kbps circuit switching network 50 to 56 Kbps circuit switching network 52
There is no inconvenience in communicating with.

Therefore, the originating data terminal device is a 48 Kbps or 64 Kbps data terminal device as described above,
These data terminals are connected to the circuit switching network 50 of 64 Kbps via the ISDN terminal 53, and the 64 Kb
When connecting from the circuit switching network 50 of ps to the circuit switching network 52 of 56 Kbps, the ISDN terminal device 53 (source ISD
In the N terminal device), the clock speed of the R point clock generation circuit is forcibly changed to 56 Kbps.

[0008]

Such a change of the R-point clock speed requires a call to the communication speed menu provided in the ISDN terminal device by the exchange of the connection destination before the call is made when it is necessary. The system is set by the R-point clock setting processing sequence of Bicall. With this method, the circuit switching network 52 of 56 Kbps
When sending to, the communication speed is 48Kbps or 64Kb
When the data terminal device is ps, the communication speed (R point clock) of the data terminal device 53 is set to 56 Kbps.
Further, when transmitting to the circuit switching network 51 of 64 Kbps, the communication speed is set to suit the data terminal device.

Therefore, in this system, the call-by-call R-point clock setting processing sequence required for it depending on the communication speed of the data terminal equipment and the circuit switching network of the callee is obtained by the switchboard of the connection destination before the call is made. Must be exchanged. When the communication speed of the data terminal device is frequently changed, smooth communication is hindered.

The present invention was created in view of such technical problems, and can automatically set an R-point clock suitable for a communication system to be formed in a plurality of ISDNs having different communication speeds. It is an object of the present invention to provide an R point clock automatic setting system.

[0011]

FIG. 1 shows a principle block diagram of the invention according to claim 1, and FIG. 2 shows a principle block diagram of the invention according to claim 2.

According to the first aspect of the invention, as shown in FIG. 1, in order to enable communication between a plurality of ISDNs having different communication speeds, the R point clock of the R point clock output circuit 1 is made variable. IS that has an ISDN terminal device
When making a call to the DN, along with the path setting information with the destination,
Input means 2 for inputting the R point clock speed identification information, clock change control means 3 for outputting change information in response to the input R point clock speed identification information, and the R point clock output in response to the change information The R point clock changing means 4 for changing the R point clock output from the circuit 1 is provided.

According to the second aspect of the invention, as shown in FIG. 2, in order to enable communication between a plurality of ISDNs having different communication speeds, the R point clock of the R point clock output circuit 1 is made variable. IS that has an ISDN terminal device
Extraction means 5 for extracting the user speed information in the call setting message received upon incoming to the DN, clock change control means 6 for outputting change information in response to the extracted user speed information, and response to the change information To change the R-point clock output from the R-point clock output circuit 1.
The point clock changing means 4 is provided.

[0014]

In the invention according to claim 1, I is added to ISDN.
In the transmission from the data terminal device connected via the SDN terminal device, the R point clock speed identification information is input from the input means 2 together with the path setting information with the destination, and is supplied to the clock change control means 3. The change information is output from there. This change information is used by the R point clock changing means 4 to change the R point clock output from the R point clock output circuit 1.

This change is input depending on whether the called party is one of the recipients, that is, the originating ISDN.
According to the difference between the communication speed with the incoming ISDN and the communication speed with the incoming ISDN.
Since the point clock speed identification information is input, the R point clock speed identification information is used to automatically detect the R point clock without taking the R point clock setting processing sequence via the ISDN communication system used for path setting. Switch.

This relationship also applies to the invention according to claim 2. That is, in the incoming call, the R point clock speed identification information is replaced with the user speed information in the call setting message received upon the incoming call, and the change information is output from the clock changing means 6 in response to the user speed information. There are differences. The effect is the same.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the invention according to claims 1 and 2 will be described below with reference to FIGS. 3, 4, 5 and 6 to 10.

In this embodiment, a program for executing the processing flow as shown in FIGS. 3 and 4 is stored in the memory 33 shown in FIG. 7, and the memory 33 has a circuit switching network of any communication speed ( A program (not shown) for registering identification information (a dial number such as a special telephone number) for identifying whether it is an ISDN exchange network) is also registered. And
It is intended to effectively use the user information included in the conventionally known call setup message shown in FIG. Other matters are the same as those shown in FIGS. 6 to 10.

3, FIG. 4, and FIG. 7, the R-point clock output circuit of the R-point interface circuit 34 corresponds to the R-point clock output circuit 1 of FIG. 1 and FIG. , Corresponding to the input means 2 of FIG. A program for executing the steps S1 and S3 shown in FIG. 3 stored in the microprocessor 32, the memory 33, and the memory 33 corresponds to the clock change control unit 3 in FIG. 1, and is stored in the microprocessor 32, the memory 33, and the memory 33. The program for executing the storing step S4 shown in FIG. 3 or the storing step S4 shown in FIG. 4 corresponds to the clock changing unit 4 in FIG. Microprocessor 3
2, the memory 33, and the program stored in the memory 33 and executing the steps S1 and S3 shown in FIG. 4 correspond to the clock change control means 6 of FIG.

The operation of one embodiment of the invention according to claim 1 and claim 2 which is carried out in the ISDN shown in FIG. 6 will be described below. The explanation is about the circuit switching network of 64Kbps and 5
Take communication with a 6 Kbps circuit switched network as an example.

Prior to starting the operation of the ISDN terminal device, whether it is a call from the data terminal device to the circuit switching network 51 of 64 Kbps or a call from the data terminal device to the circuit switching network 52 of 56 Kbps. Identification information (a dialed number such as a special telephone number) shown is registered and stored in the memory 33.
The special telephone number is, for example, 111, which indicates that the data terminal device is calling the 56 Kbps ISDN exchange. The initial value of the R-point clock generation circuit in the R-point interface circuit 34 of the data terminal device is 64 Kbps.

When a call is made from the data terminal device to the circuit switching network 52 at 56 Kbps, the special telephone number 111 is added before the telephone number of the other party to dial. ISDN that received the dial from the data terminal
The terminal device 53 determines whether or not the received special telephone number 111 is registered (see S1 in FIG. 3).
If not registered (see N in S1 of FIG. 3), the microprocessor 32 keeps the initial value of 64 Kbps of the R point clock generation circuit in the R point interface circuit 34 (see S2 of FIG. 3).

If the matching special telephone number is registered (see Y in S1 of FIG. 3), it is determined whether or not the registered special telephone number is 111 indicating 56 Kbps (see S3 of FIG. 3). ). If the determination is affirmative (see Y in S3 of FIG. 3), the microprocessor 32 changes the clock of the R point clock generation circuit in the R point interface circuit 34 to the clock of 56 Kbps. As a result, the data from the data terminal device can be connected to the partner data terminal device via the circuit switching network 50 of 64 Kbps and the circuit switching network 52 of 56 Kbps in the frame format shown in FIG. Therefore, in response to the 64 Kbps clock,
It is possible to automatically switch the R-point clock required for communication while preventing bit loss in the bit number 8 that occurs when communication is performed in the frame format shown in 0.

A call is made from the data terminal equipment 58 (see FIG. 6) connected to the 56 Kbps circuit switching network 52 to the data terminal equipment 56 connected to the 64 Kbps circuit switching network 50, and both of them are transmitted as in the conventional case. A path setting sequence (path setting process) for setting a path is exchanged between them, but at that time, the transfer capability in the call setting message transferred from the ISDN exchange 50 to the ISDN terminal device 53 on the receiving side (see FIG. 5). ) Is set.
If not (see N in S1 in FIG. 4), ISDN of the called side
The microprocessor 32 of the terminal device 53 uses the initial value 6 of the R point clock generation circuit in the R point interface circuit 34.
It remains 4 Kbps (see S2 in FIG. 4).

If the transfer capability is set (see Y in S2 of FIG. 4), it is determined whether or not the user speed within the transfer capability (see octet 5a of FIG. 5) is 56 Kbps. The clock speed of the R-point clock generation circuit, which was 64 Kbps until then, is reduced to 56 Kbps (see S3 in FIG. 4). Therefore, even in this case, the IS
Since the frame format of the data transmitted from the DN terminal device 53 is the frame format shown in FIG. 8, a bit missing in the bit number 8 that occurs when communication is performed in the frame format shown in FIG. 10 in response to the clock of 64 Kbps. It is possible to automatically switch the R-point clock required for communication while preventing the above.

In the above embodiment, the data transmission / reception is performed between the 64 Kbps circuit switch and the 56 Kbps circuit switch network, and the 56 Kbps data terminal device is connected to the 64 Kbps circuit switch network. As I explained, 64Kb
The present invention is equally applicable to the case where a 48 Kbps data terminal device is connected to a ps circuit switching network, and also when data is transmitted and received between a 64 Kbps circuit switching device and a 48 Kbps circuit switching device. The present invention can be applied. This is because the invention according to claim 1 and claim 2 can not seek protection only when the communication speed of the circuit switching network is a certain specific value, and a system capable of communicating with the circuit switching network. The present invention has expandability for connecting a data terminal device capable of forming a network to the circuit switching network.

[0027]

As described above, according to the present invention, the identification information of the destination ISDN is used when making a call, and the call setting message is exchanged between the originating and terminating ISDN terminal devices when the path is set when a call is received. Since the speed information of the destination ISDN is used to set the R point clock,
In the originating and terminating ISDN exchange communication system, the setting of the R point clock setting processing sequence can be eliminated altogether, and the R point clock of the ISDN terminal device can be automatically set to a value that does not hinder data transmission and reception. This enables efficient communication between communication networks having different clocks.

[Brief description of drawings]

FIG. 1 is a block diagram of the principle of the invention according to claim 1.

FIG. 2 is a principle block diagram of an invention according to claim 2;

FIG. 3 is a diagram showing an R-point clock switching processing flow at the time of transmission.

FIG. 4 is a diagram showing an R-point clock switching processing flow when an incoming call arrives.

FIG. 5 is a diagram showing a content structure of a call setting message.

FIG. 6 is a configuration diagram of a composite ISDN.

FIG. 7 is a configuration diagram of an ISDN terminal device.

FIG. 8 shows 6 frames from a data terminal device of 56 Kbps.
It is a figure which shows the frame format at the time of transferring to a circuit switching network of 4 Kbps.

FIG. 9 shows 6 frames from a 48 Kbps data terminal device.
It is a figure which shows the frame format at the time of transferring to a circuit switching network of 4 Kbps.

FIG. 10 is a diagram showing a frame format in the case of transferring a frame from a data terminal device of 64 Kbps to a circuit switching network of 64 Kbps.

[Explanation of symbols]

 1 R point clock output circuit 2 R point clock speed identification information input means 3 Clock change control means 4 R point clock change means 5 Extraction means 6 Clock change control means 30 ISDN line interface circuit 31 Bus 32 Microprocessor 33 Memory 34 R point interface Circuit 56,60 Data terminal device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location H04L 12/02 H04Q 3/58 8627-5K 11/04

Claims (2)

[Claims] 1. A plurality of ISs having different communication speeds.
In a composite ISDN having an ISDN terminal device that makes the R point clock of the R point clock output circuit (1) variable in order to enable communication between DNs, at the time of transmission, together with the path setting information with the destination, the R point clock speed Input means (2) for inputting identification information, clock change control means (3) for outputting change information in response to the inputted R point clock speed identification information, and said R point clock output in response to change information An R-point clock automatic switching system, characterized in that R-point clock changing means (4) for changing the R-point clock output from the circuit (1) is provided. 2. A plurality of ISs having different communication speeds.
In a composite ISDN having an ISDN terminal device that makes the R-point clock of the R-point clock output circuit (1) variable in order to enable communication between DNs, the user speed information is extracted from the call setup message received when an incoming call arrives. Extracting means (5), clock change control means (6) for outputting change information in response to the extracted user speed information, and output from the R-point clock output circuit (1) in response to the change information And an R point clock changing means (4) for changing the R point clock.