JPH05327699A - Control method for modem interface signal with the use of h channel - Google Patents

Abstract

PURPOSE:To unify the communication control program when B and H channels of ISDN interface are in use. CONSTITUTION:The communication controller provided with a protocol control section 1 transmitting/receiving a modem interface signal comprising a data signal, a modem control signal, a modem state signal, a speed matching section 3 multiplying and decomposing the modem interface signal into a frame signal according to a prescribed speed matching form at the transmission reception of the B channel, and a channel mode changeover section 3 connecting to the protocol control section 1 and the speed matching section 3, selecting a frame signal from the protocol control section 1 in the case of transmission reception of the H channel, selecting a frame signal resulting from multiplexing and decomposing a modem interface signal from the protocol control section 1 by the speed matching section 3 in the case of transmission reception of the B channel and connecting the selected signal to the line, is provided with a modem signal loopback section 4 looping back the modem control signal to a modem state signal to the protocol section 1 in the case of the transmission reception of the H channel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a modem interface signal when the H channel of an integrated services digital communication network (ISDN) is used.

In data communication networks in recent years, new communication networks such as integrated service digital communication networks (hereinafter referred to as ISDN) and high-speed digital leased lines have appeared. For this reason, when connecting a terminal using a modem interface to the ISDN or the like conventionally, the communication control program is changed to New communication network (ISD
N).

For example, the ISDN user / network interface is usually called an I interface.
The interface is currently the basic interface (2
B + D channel), primary group interface (23B + D channel), and high-speed wideband interface. The primary group interface uses a modem interface signal to provide a rate matching function. It is possible to use a channel and an H channel that does not use a modem interface signal, that is, does not perform rate matching but can provide a high speed data service.

When a personal computer terminal, a facsimile terminal, or the like that performs data communication using the modem interface signal is connected to the ISDN of the primary group interface that uses the modem interface signal, a communication control program, Since it is necessary to prepare two systems, a system that requires speed matching control and a system that does not require speed matching control, in the communication control program for the ISDN, A control method that does not require the use of speed matching, the distinction of unused is needed.

[0005]

2. Description of the Related Art FIGS. 2 to 4 are diagrams for explaining a conventional ISDN use technique. FIGS. 2 (a1), (a2), and (a3) show a case where a B channel is used, and FIG. b1) and (b2) show the case where the H channel is used, and FIG. 4 (c) shows the case where the B channel and the H channel are switched and used.

First, FIG. 2 (a1) illustrates the frame structure of the B channel of the ISDN primary interface. The
As shown in the figure, the B channel of the ISDN primary interface has a transmission rate of 64 kbps and a time slot (TS) consisting of 8 bits, 24 times TS0 to TS23.
One frame consists of time slot + flag slot (F).

The user information amount when using the B channel is 8,16,32,64 kbps. For example, when connecting a personal computer terminal of 2,400 bps, the above user information amount of 8 kbps is used. Data communication is carried out.

Specifically, data communication is performed using 1 bit of the time slot (TS) consisting of 8 bits, but since it has a transmission capacity of 8 kbps with respect to 2.4 kbps, it is predetermined. The modem interface signal is inserted into the frame, that is, the data signal and the modem control signal are multiplexed to form one frame, which is connected to the ISDN line.

FIG. 2 (a2) shows a configuration example of a communication control device of a terminal for performing data communication using the B channel, for example, a personal computer terminal, and FIG. 2 (a3) shows, for example, CCITT Recommendation V.2.
An example of the configuration of modem control signals (ER, RS) and modem status signals (CS, DR, CD) specified in 4 is shown.

In FIG. 2 (a3), the modem control signal (ER)
Indicates a terminal ready, the terminal ready (ER) is sent to the partner terminal, and is received as a data set ready (DR) by the partner terminal.

Further, when the transmission side terminal transmits the communication request (RS) after receiving the data set ready (DR) from the partner terminal, the partner terminal receives it as a carry detection (CD). When the other terminal is ready to send data, a clear-to-send (CS) is sent from the other terminal, and when both parties recognize the clear-to-send (CS), the sending terminal The actual data signal (SD, RD) is transmitted and received between and the other terminal.

When the above operation is performed with the ISDN network terminating device (DSU), as described above, in the terminal device, the data signal (SD, RD), the modem control signal (ER, RS) Then, the modem interface signal including the modem status signal (CS, DR, CD) is transmitted at the transmission speed of the terminal as shown in FIG. 2 (a1).
(For example, 2.4 kbps, 9.6 kbps) is multiplexed into one frame and transmitted to the ISDN line.

The above-described multiplexing operation of the modem interface signal is performed by the communication control device of the terminal shown in FIG. 2 (a2) by the modem data signal (SD, R
D), modem control signals (ER, RS), and modem status signals (C
S, DR, CD) are multiplexed in the speed matching unit 3.

Specifically, a plurality of bits of the same data signal are placed in each frame by a so-called bit repetition method in accordance with the transmission speed, and a modem control signal is placed in an empty frame between the plurality of bits of the modem data signal. Therefore, speed matching can be performed by inserting a modem status signal.

For example, in a line having a transmission rate of 64 kbps, 1 bit is repeated twice in 48 frames of 80 frames to carry a 24-bit data signal (in empty frames, as described above, By carrying a modem control signal), it is possible to perform data communication of 2.4 kbps by converting the intermediate speed of 8 kbps and converting the intermediate speed of 8 kbps to 64 kbps.

Next, the H of the primary group interface of the ISDN
Figure 3 shows the operation when data communication is performed using channels.
An explanation will be given using (b1) and (b2). The data communication by the H channel is used when the data communication is performed at a higher speed than a personal computer terminal or the like using the modem interface signal.

FIG. 3 (b1) shows the frame structure of the slowest H ₀ channel of the H channels.
It has a transmission speed of 64 kbps, and performs high-speed transmission of 384 kbps with 6 time slots (TS) consisting of 8 bits as one frame.

In this case, each terminal simply puts a data signal of a predetermined number of bits in the allocated time slot, and as described with reference to FIGS. 2 (a1) to 2 (a3).
It does not have a speed matching function, that is, a multiplexing function.

Therefore, the communication control device for transmitting / receiving the H channel has the structure shown in FIG. 3 (b2), and there is no speed matching unit. In the examples described in FIGS. 2 and 3, separate communication control devices are required for transmitting / receiving the B channel and transmitting / receiving the H channel.

FIG. 4 (c) shows the configuration of the communication control device of the terminal device when the channel mode switching unit 2 switches between the data communication by the ISDN B channel and the data communication by the H channel. It is shown.

As shown in the figure, in this case, a protocol control unit 1 for transmitting and receiving a modem interface signal composed of a modem data signal, a modem control signal and a modem status signal, and a protocol control unit 1 connected to the protocol control unit 1. , B
When transmitting and receiving a channel, according to a predetermined rate matching format,
Multiplexing the modem interface signal with a frame signal,
It is connected to the speed matching unit 3 to be decomposed, the protocol control unit 1 and the speed matching unit 3, and selects the frame signal from the protocol control unit 1 for transmission / reception of the H channel, and for transmission / reception of the B channel. The ISDN line is controlled by including a channel mode switching unit 2 for selecting a frame signal obtained by multiplexing and decomposing the modem interface signal from the protocol control unit 1 by the speed matching unit 3 and connecting it to the line.

The above example has been described by taking ISDN as an example.
The same applies to high-speed digital leased line networks.

[0023]

Therefore, for example, the IS
In the communication control device that controls the DN, the communication control program that controls the B channel and the H channel uses a modem control signal and a data communication by the B channel that performs speed matching by using the modem status signal according to the type of the channel. It is necessary to distinguish the data communication by the H channel which does not use the modem control signal and the modem status signal, that is, does not perform rate matching.

In view of the above-mentioned conventional drawbacks, the present invention provides, for example,
To provide a modem interface control method capable of constructing a program module that does not need to distinguish between use and non-use of speed matching for a modem signal control in a communication control program in a communication control device for controlling ISDN, Specifically, it is an object of the present invention to provide a modem interface control method capable of performing data communication by making it appear as if the data communication uses the B channel even in the data communication using the H channel. To do.

[0025]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 1 (a) shows a configuration example of a communication control device of the present invention, and FIG. Shows schematically the configuration of the modem signal folding section of the present invention. The above problems are solved by the modem interface control method configured as follows.

A protocol control unit 1 for transmitting and receiving a modem interface signal composed of a modem data signal, a modem control signal and a modem status signal, and the protocol control unit 1
And a speed matching unit 3 for multiplexing the modem interface signals and assembling them into a frame signal according to a predetermined speed matching format when transmitting / receiving the B channel, or for decomposing the frame signal from the line into a modem interface signal, It is connected to the protocol control unit 1 and the speed matching unit 3, and the protocol control unit is used for transmission / reception of the H channel.
The frame signal from 1 is selected, and the modem interface signal from the protocol control unit 1 is selected for transmission / reception of the B channel, and the frame signal multiplexed by the speed matching unit 3 is selected and transmitted to the line. In a communication control device for controlling a high-speed digital circuit network such as ISDN, which is provided with a channel mode switching unit 2 for decomposing a frame signal from the
In the case where the modem control signal is returned to the protocol control section 1 by providing a modem signal return section 4 for returning the modem control signal to the modem status signal and data communication is performed using the H channel,
By controlling the modem control signal sent from the protocol control unit 1 to be returned by the modem signal return unit 4, the H mode is the same as that of the B channel.
It is configured to send and receive channels.

[0027]

That is, the communication control device of the present invention is a protocol control unit for transmitting and receiving a modem interface signal including a modem data signal, a modem control signal and a modem status signal.
1, and is connected to the protocol control unit 1 and, when transmitting / receiving a B channel, multiplexes the modem interface signal according to a predetermined speed matching format to assemble into a frame signal,
Alternatively, the speed matching unit 3 for decomposing the frame signal from the line into a modem interface signal and the protocol control unit
1 and the speed matching unit 3, the frame signal from the protocol control unit 1 is selected for transmission / reception of the H channel, and the modem interface signal from the protocol control unit 1 is transmitted / received for the B channel, A channel mode switching unit 2 that selects the frame signal multiplexed by the speed matching unit 3 and sends it to the line or decomposes the frame signal from the line into a modem interface signal, for example, IS
A communication control device for controlling a DN line is provided with a modem signal loopback section 4 for looping a modem control signal back to a modem status signal for the protocol control section 1 when transmitting / receiving an H channel.

The modem signal loopback unit 4 loops the modem control signal back to the modem status signal as shown in FIG. 1B when the loopback mode is instructed by the processor.

Therefore, even when the speed matching unit is not used as in the case of transmitting and receiving on the H channel, in the protocol control unit 1, the modem status signal indicates the status of the modem control signal. The communication control program can control the modem signal in the same manner as when using the same speed matching as when transmitting and receiving the B channel, and it is possible to make the modules of the communication control program common. can get.

[0030]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 described above is a diagram showing an embodiment of the present invention.

In the present invention, a protocol control unit 1 for transmitting and receiving a modem interface signal composed of a modem data signal from a terminal, a modem control signal and a modem status signal, and a B channel of the B channel connected to the protocol control unit 1 are connected. At the time of transmission and reception, according to a predetermined speed matching format, the modem interface signals are multiplexed and assembled into a frame signal, or a speed matching unit 3 that decomposes a frame signal from a line into a modem interface signal and the protocol control unit 1 , Which is connected to the speed matching unit 3, selects the frame signal from the protocol control unit 1 for H channel transmission / reception, and selects the frame signal from the protocol control unit 1 for B channel transmission / reception.
The modem interface signal from the
In the communication control device for controlling an ISDN line, for example, a channel mode switching unit 2 for selecting a frame signal multiplexed with and transmitting the frame signal from the line to a modem interface signal is provided. When transmitting / receiving the H channel, the protocol control unit 1
Means for providing the modem signal folding section 4 for folding the modem control signal back to the modem status signal is a means necessary for implementing the present invention. The same reference numerals denote the same objects throughout the drawings.

The method of controlling the modem interface signal when the H channel of the present invention is used will be described below with reference to FIG. In FIG. 1 (a), the protocol control unit 1
Is connected to processor 5 by the processor bus,
Performs serial / parallel conversion of data signals (SD, RD) and processes of various communication protocols, and if the corresponding channel of the line is the H channel, the channel mode switching unit 2 sends the data signal from the protocol control unit 1. Connect to the line as a frame signal, connect the frame signal from the line to the protocol control unit 1, and set the corresponding channel of the line to B
If the channel is a data signal, the protocol control unit 1
And the frame signal generated by being multiplexed in the speed matching unit 3 is connected to the line.

The speed matching unit 3 receives the data signal from the protocol control unit 1 and the modem signal as described above.
A frame signal is generated by multiplexing according to the transmission speed of the terminal device, and the B channel frame signal from the channel mode switching unit 2 is decomposed into a data signal and a modem signal.

Numeral 4 is a modem signal loopback unit of the present invention. Based on an instruction from the processor 5, the modem control signal from the protocol control unit 1 is connected to the loopback connection shown in FIG. 1 (b), for example. Based on the above, it returns to the modem status signal.

Therefore, the processor 5 recognizes that the B channel is transmitting and receiving, and the modem signal folding section
When instructed to 4, the modem control signal is sent back to the speed matching unit 3 without returning, and the data signal received from the channel mode switching unit 2 and the modem control signal are sent to the speed matching unit 3. , A frame signal is generated by multiplexing according to the transmission speed of the terminal device, and is sent to the line via the channel mode switching unit 2. (When the B channel frame signal is received from the line, the operation is
Since the operation is the reverse of the above, details are omitted).

The processor 5 recognizes that the H channel is transmitting and receiving, and the modem signal return section
When instructed to 4, the modem control signal, for example,
Since it is returned as a modem status signal based on the return connection shown in FIG. 2, the protocol control unit 1 can control the modem signal when speed matching is used, that is, in the same manner as the B channel. ..

Needless to say, the example of the return of the modem signal shown in FIG. 1B is merely an example, and the present invention is not limited to this return pattern.
As a modem interface signal, in FIG.
Although it was explained in the CCITT recommendation V.24 image (that is, not V.24 full set signal), it goes without saying that the signal line specified in X.21 may be used. ..

Further, although the instruction of the turn-back has been explained by the instruction from the processor 5, it is also clear that it may be given by a mechanical setting such as a switch. Further, in the present embodiment, the communication control device of the terminal connected to ISDN is taken as an example, but the same channel configuration (that is, B channel, H
The same applies to a communication control device having a channel) connected to a high-speed digital leased line network, for example.

[0039]

As described above in detail, the modem interface signal control method of the present invention uses a modem signal even in data communication that does not perform rate matching, for example, using the H channel of ISDN. Because you can
An effect that the modules of the communication control program of the communication control device can be standardized can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram (part 1) explaining a conventional ISDN use technology.

FIG. 3 is a diagram (part 2) for explaining the conventional ISDN use technology.

FIG. 4 is a diagram (part 3) for explaining the conventional ISDN use technology.

[Explanation of symbols]

1 Protocol control unit 2 Channel mode switching unit 3 Speed matching unit 4 Modem signal return unit SD, RD data signal ER, RS Modem control signal CS, DR, CD Modem status signal

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location 8020-5K H04L 13/00 309A

Claims (1)

[Claims] 1. A protocol control unit (1) for transmitting and receiving a modem interface signal composed of a modem data signal, a modem control signal and a modem status signal, and the protocol control unit.
A speed matching unit (3) that is connected to (1) and multiplexes and decomposes the modem interface signal into a frame signal according to a predetermined speed matching format during transmission and reception of the B channel; and the protocol control unit (1), It is connected to the speed matching unit (3) and H
A frame signal from the protocol control unit (1) is selected for transmission / reception of a channel, and a modem interface signal from the protocol control unit (1) is selected for transmission / reception of a B channel.
In a communication control device for controlling a high-speed digital line, which is equipped with a channel mode switching unit (2) for selecting a frame signal multiplexed and decomposed by the speed matching unit (3) and connecting it to the line, when transmitting / receiving an H channel. For the protocol control section (1), a modem signal loopback section (4) for looping back the modem control signal to a modem status signal is provided to control the transmission and reception of the H channel with the same modem interface as the B channel. A method of controlling a modem interface signal when the H channel is used.