JP2001268265A - Terminal adaptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a terminal adaptor that can conduct normal communication, even on the occurrence of a fault in a layer 1 control section or even when an ISDN terminal interface of an exchanger with a communication unit connected thereto becomes faulty. SOLUTION: A main layer 1 controls sections 11a and 11b and a back-up layer 1 control sections 12a and 12b are connected respectively to separate lines, the main layer 1 control sections 11a of the one terminal adaptor 3a is connected to a backup layer 1 control sections 12b of the other terminal adaptor 3b. The back-up layer 1 control sections 12a of the one terminal adaptor 3a is connected to the back-up layer 1 control sections 12b of the other terminal adaptor, 3b so as to attain communication even on the occurrence of a fault of a layer 1 control section or on the occurrence of a fault in one ISDN terminal interface circuit of an exchange 1, to which a communication unit is connected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated services digital network (ISDN) for communicating over an ISDN.
More particularly, the present invention relates to an ISDN communication device suitable for performing communication and communication by using the B1 channel and the B2 channel constituting the ISDN basic interface individually.

[0002]

2. Description of the Related Art The basic interface of ISDN is 2B +
D. That is, the information channel B
There are two channels and one D channel, which is a control channel. Transmission speed is 64Kb for B channel
ps and D channel are 16 Kbps.

[0003] The two B channels are a B1 channel and a B2 channel.
The channels are defined as independent channels, and both B channels may be used simultaneously by one communication system, or may be used separately by different communication systems.

In a conventional communication system, if the number of communication devices is assumed to be N in order to secure communication at the time of an interface failure with the communication devices, the exchange has an ISDN terminal interface circuit of N + α, which is larger than the number of communication devices. In the event of a failure, the system was temporarily switched.

[0005]

In the former case of the prior art, since both B channels are usually connected to a common layer 1 control unit, a failure occurs in the layer 1 control unit of the communication apparatus in either case. It has been difficult to continue communication when a communication error occurs or when there is a failure in the ISDN terminal interface circuit of the exchange to which the communication device is connected.

In the latter case, the number of rescue lines at the time of failure is + α, which is larger than the number of communication devices. Also,
If the layer 1 control unit of the communication device that interfaces the terminal with the exchange breaks down, the terminal cannot be used.

[0007] The present invention solves such a problem, and comprises two layer 1 control units and two connection ports to a line. In the event of an ISDN terminal interface circuit failure of the exchange connected to the main layer 1 control unit, the other backup layer 1 control unit is used.
The use of the ISDN terminal interface circuit of the exchange connected to it, and the use of another B channel by another B
It is an object of the present invention to provide a terminal adapter that enables communication at the time of a failure by changing a channel or the like.

[0008]

A first aspect of the present invention is a communication device for ISDN which performs communication via an integrated services digital network (ISDN), and has one physical port to which a terminal device can be connected. The above-described apparatus is characterized in that two layer 1 control units are provided, one of which is a normal operation system and the other is a standby system, each of which is connected to a different line.

In a second aspect of the present invention, the first aspect further comprises a fault detecting section for detecting that a fault has occurred in the layer 1 control section. It is characterized in that the other standby system is operated.

In a third aspect of the present invention, in the second aspect, when the terminal adapters communicate with each other, a normal operation system layer 1 control unit of one terminal adapter and another terminal adapter of the other terminal adapter are connected. A standby system layer 1 control unit is connected, and a standby system layer 1 control unit of one terminal adapter is connected to a normal operation system layer 1 control unit of the other terminal adapter.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an ISDN of an exchange according to an embodiment of the present invention.
FIG. 2 is a block diagram illustrating a communication system when two terminal adapters are connected to a terminal interface circuit.

In FIG. 1, an exchange 1 is connected to two ISDN communication systems 2 having the same configuration, and is configured to transmit and receive data to and from each other through the exchange 1. In the following description, the upper communication system 2 will be referred to as the transmitting side, a will be added after the number, the lower communication system 2 will be set as the receiving side, and b will be added after the number.

In the ISDN communication system 2, a terminal adapter 3 is connected to the exchange 1, and the terminal adapter 3 has one or more physical ports to which a data terminal or an analog terminal can be connected.
Is connected.

The terminal adapter 3 is an IS according to the present invention.
It functions as a DN communication device, is started by the terminal 4, and connects to the other party via the exchange 1 using the B1 channel or the B2 channel.

As shown in FIG. 1, in the present invention, a main port of a terminal adapter 3a (hereinafter referred to as TA3a) is connected to an ISDN terminal interface circuit a (hereinafter referred to as BRIa) mounted on the exchange 1 by a BRIA connection cable 5. 31a and a terminal adapter 3b (hereinafter T
A3b) is connected to the backup port 32b. Further, the backup port 32a of the TA3a and the main port 31b of the TA3b are connected to the ISDN terminal interface circuit b (hereinafter, referred to as BRIb) mounted on the exchange 1 with the BRIb connection cable 6.

When the terminal 4a and the terminal 4b communicate with each other when the exchange 1 (line) and the main ports 31 of both TA3s are normal, data transmitted from the terminal 4a is transmitted from the main port 31a of the TA3a. Sent, B
An RIa connection cable 5 connects to the BRIa of the exchange 1. The data sent to the BRIa is switched to the BRIb by the exchange 1. After that, the data of the terminal 4a is BR
The Ib is connected to the main port 31b of the TA 3b by the BRIb connection cable 6, and transmitted from the TA 3b to the terminal 4b.

Thus, the exchange 1 (line) and the TA3
Is normal, TA3a and TA3b communicate with each other using the main port 31a and the main port 31b.

FIG. 2 is a block diagram of the terminal adapter (TA) 3 according to the present invention. In the figure, TA3
Is a physical interface with the exchange 1, which is a main port 31 used for normal operation, similarly, a physical interface with the exchange 1, and a backup port 32 which operates in the event of a failure. A main layer 1 control unit 11 used for operation, a backup layer 1 control unit 12 which performs data format conversion and operates in the event of a failure, and a B
It is composed of a B channel control unit 14 for distributing channels and connecting to physical ports.

FIG. 3 is a block diagram of the layer 1 control unit 11. In the figure, a layer 1 control unit includes a data format conversion unit 111, a frame decomposition unit 112,
It is composed of a frame assembly unit 113 and a failure monitoring unit 114.

When an incoming call is received, the frame is received and code conversion is performed from AMI to NRZ by the data format conversion unit 111 in the main layer 1 control unit 11.
The B1 channel and the B2 channel
The channel is decomposed into two channels, and the B channel interface unit 14 connects to the physical port using either the B1 channel or the B2 channel.

When a call is transmitted, the data terminal 4 connected to the TA 3 is activated and the frame assembling unit 11
3 controls the channel, and the data format conversion unit 1
11 is converted from NRZ to AMI and connected to the exchange 1.

Next, an operation when a failure occurs in the main layer 1 control unit 11a, the main port 31a or the BRIa of the communication system 2a will be described.

When a failure is detected by the failure monitoring unit 114 in the main layer 1 control unit 11a, the B channel control unit 14a selects the B channel used by the physical port and the layer 1 control unit according to the failure information. I do. In this case, the B channel used is the B1 channel, and the layer 1 control unit used is the backup layer 1 control unit 12a.

The outgoing data from the terminal 4a is transmitted using the backup port 32a of the communication system 2a. The data transmitted from the backup port 32a is transmitted to the BRIb of the exchange 1 via the BRIb connection cable 6. The data is switched by the exchange 1 to the BRIb in which the corresponding terminal is accommodated. Data from the terminal 4a is received from the BRIb by the BRIb connection cable 6 at the main port 31b of the TA 3b, and the B2 channel is selected by the B channel control unit 14b.
The data is loaded on the channel and sent to the terminal 4b.

Next, the operation when a failure occurs in the main layer 1 controller 11b, the main port 31b or the BRIb of the communication system 2b will be described.

When a failure is detected by the failure monitoring unit 114 in the main layer 1 control unit 11b, the B channel control unit 14b selects the B channel used by the physical port and the layer 1 control unit based on the failure information. I do. In this case, the layer 1 control unit used is the backup layer 1
It becomes the control unit 12b.

The outgoing data from the terminal 4a is transmitted using the main port 31a of the communication system 2a, with the data placed on the B1 channel selected by the B channel control unit 14a. The data transmitted from the main port 31a is transmitted to the BRI
a. The data is switched by the exchange 1 to the BRIA in which the terminal is accommodated.
Data from the terminal 4a is received from the BRIa to the backup port 32b of the TA3b via the BRIA connection cable 5, the B2 channel is selected by the B channel control unit 14b, and data is loaded on the B2 channel.
Send to b.

Next, the operation when a failure occurs in the main layer 1 control unit 11a or main port 31a on the communication system 2a side and in the main layer 1 control unit 11b or main port 31b on the communication system 2b side will be described.

When a failure is detected by the failure monitoring unit 114 in the main layer 1 control unit 11a, the B channel control unit 14a selects the B channel used by the physical port and the layer 1 control unit based on the failure information. I do. In this case, the layer 1 control unit used is the backup layer 1
It becomes the control unit 12a.

Next, when a failure is detected by the failure monitoring unit 114 in the main layer 1 control unit 11b, the B channel control unit 14b determines the B channel used by the physical port and the layer 1 control based on the failure information. Select a department. In this case, the layer 1 control unit used is the backup layer 1 control unit 12b.

The outgoing data from the terminal 4a is transmitted using the backup port 31a of the communication system 2a with the data loaded on the B1 channel selected by the B channel control unit 14a. The data transmitted from the backup port 32a is transmitted to the BRIb of the exchange 1 via the BRIb connection cable 6. The data is switched by the exchange 1 to the BRIA in which the terminal is accommodated. The data from the terminal 4a is converted from BRIa to BRI
a is received at the backup port 32b of the TA 3b by the connection cable 5, and
One channel is selected, and data is loaded on the B1 channel and sent to the terminal 4b.

[0033]

As described above, two layer 1 control units are provided, one of which is a normal operation system and the other is a standby system, each of which is connected to another line. Time or one I of the exchange 1 to which the communication device is connected.
Normal communication is possible even when the SDN terminal interface circuit fails.

[Brief description of the drawings]

FIG. 1 is a diagram showing a communication system of the present invention.

FIG. 2 is a block diagram showing an internal configuration of the terminal adapter of the present invention.

FIG. 3 is a block diagram showing an internal configuration of a layer 1 control unit of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Switchboard 2 Communication system 3 Terminal adapter 4 Terminal 11 Main layer 1 control part 12 Backup layer 1 control part 14 B channel control part 31 Main port 32 Backup port

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5K019 AA08 BA52 BA62 BA65 CA07 CC01 EA28 5K034 AA05 EE13 FF09 FF14 HH01 HH03 HH05 HH06 HH12 KK04 PP05 SS01 TT01 5K035 AA03 BB04 CC10 DD01 FF03 HH04V03 5H05V05

Claims (3)

[Claims] 1. An integrated services digital communication network (ISD)
N) a communication device for ISDN communicating via
A terminal having at least one physical port to which a terminal device can be connected, comprising two layer 1 control units, one of which is a normal operation system and the other is a standby system, each of which is connected to a different line. adapter. 2. The apparatus according to claim 1, further comprising a fault detecting section for detecting that a fault has occurred in the layer 1 control section, wherein when a fault is detected in one operating system, the other standby system is operated. The terminal adapter according to claim 1. 3. The communication system according to claim 1, wherein said terminal adapter is connected to a normal operation layer 1 control unit of one terminal adapter and a standby layer 1 control unit of the other terminal adapter. 3. The terminal adapter according to claim 2, wherein the standby layer-1 control unit of one terminal adapter is connected to the normal operation layer-1 control unit of the other terminal adapter to perform communication.