JPH03159445A - Communication controller - Google Patents

Abstract

PURPOSE:To continue the data transmission of an H0 channel by selecting a serial transmission line for B channel without a fault among the serial transmission lines for B channel used for the H0 channel so as to establish a data link at the time of establishing the data link of the H0 channel for high speed communication. CONSTITUTION:At the time of establishing the data link of the H0 channel, a channel selection part 12 in a processor 5 selects the serial transmission line B1 corresponding to the newest time slot 1 as the establishment of the data link of the H0 channel. When there is the fault in the serial transmission line B1, a fault detection part 11 outputs a prescribed instruction signal to the channel selection part 12. It outputs a control signal for a layer 1 control part 3 to select a serial transmission line B2 instead of the previously selected serial transmission line B1, for example. Thus, the layer 1 control part 3 establishes the data link of the H0 channel using the serial transmission line B2 without the fault.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a communication control device that accommodates an ISDN primary group interface, which is well known as a multipurpose user network interface.

(Conventional technology) ISDN (Integrated Service)
Digital Network) is a voice and data network that has been handled by conventional analog communication networks and individual networks. facsimile. It is a comprehensive network that connects various services such as image communication using digital exchanges and digital paths.

The ISDN primary group interface has 23 B channels with a communication speed of 64 Kbit/s and 6
It consists of one 4K bit/sec D channel. B
The channels are used for data transmission, and the D channel is used for transmitting call control information. In addition, any 6 of the 23 B channels are bundled to create an H channel with a communication speed of 384 Kbits/sec.

Channel data links are also possible.

Therefore, the B channel provides a data link for low-speed multiplex communication, while the H0 channel provides a data link for high-speed communication.

FIG. 2 shows a block diagram of a conventional communication control device. This communication control device accommodates an ISDN primary group interface.

In the figure, a communication control device 1 is connected to an IS[IN network 2].

This device includes a layer 1 control unit 3 that controls the physical layer of the interface, a layer 2 control unit 4 that controls the data link layer of the interface, a processor 5 that controls the operation of the entire device, and an operating program for the processor 5. A memory unit 6 for storing and temporarily storing data.
It is equipped with The layer 1 control section 3 and the layer 2 control section 4 are connected by a physical path 7 including serial transmission lines B1 to B23 provided as many as the number of channels for low-speed multiplex communication. That is, this physical path 7 is composed of serial transmission paths B1 to B23 that serially transmit signals for 23 B channels, and a serial transmission path D that transmits D channel signals for call control information. ing. Call control information for identifying the contents of messages sent and received between the communication control device 1 and the ISDN network 2 is transmitted to this D channel. In addition, the serial transmission line 31 of the physical path 7
~B23 respectively contain transmission data. Received data, transmission/reception timing signals, etc. are transferred.

APD (Link Access Proc
edure on the Dchannel)
The control unit 8 is a circuit that manages the transfer of this call control information.

In addition, the layer 2 control unit 4, the processor 5, and the memory unit 6
are connected by a pass line 9.

Further, a control line 10 is provided between the processor 5 and the layer I control section 3. A signal for controlling the selection of the physical path 7 between the layer 1 control section 3 and the layer 2 control section 4 is transmitted to this control line 10 .

Before explaining the operation of the above device, first, the signals transmitted and received by this communication control device 1 will be explained.

FIG. 3 is an explanatory diagram showing the format of messages sent and received over the ISDN network.

In the figure, one frame of this message consists of 24 time slots. Each time slot has an 8-bit configuration, and time slot 1 to time slot 23 are B channels, and time slot 24 is a B channel.
is used for the D channel. The F bit provided at the beginning of the frame is used as a synchronization signal. for example,
If all 23 time slots for B channels are used simultaneously, then for each channel
Serial transmission lines 81 to B23 of the physical path 7 shown in the figure are used one by one. Each serial transmission line BINB23
In this case, the 8-bit signal included in one time slot shown in FIG. 3 is serially transmitted. This results in
Multiplex communication of up to 23 channels is possible.

On the other hand, when high-speed communication is to be performed, this fact is notified in advance by a channel identifier included in call control information transmitted and received via the D channel.

That is, with this channel identifier, 6 time slots out of 23 time slots for the B channel shown in FIG. Allocated for channels. In this case, the layer 1 control unit 3 shown in FIG.
The data of the a channel is collectively converted into serial data, and a data link of the H0 channel is established using any serial transmission path selected by the processor 5, for example, the serial transmission path B1.

(Problem to be Solved by the Invention) By the way, as explained earlier, the LAPD control unit 8 recognizes the identifier indicating that any six channels out of the 23 B channels are to be used as Ha channels. When the processor 5 receives this notification, the processor 5 establishes a data link using the serial transmission path prepared for the channel with the lowest number.

That is, for example, for the B channels from time slot 1 to time slot 23 shown in FIG. 3, the serial transmission lines B1 to B23 of the physical path 7 shown in FIG.
For example, if a H0 channel data link using time slots 1, 4.6, 7, and 8.9 is requested, the serial transmission line B1 for time slot 1 is allocated in numerical order. Automatically selected for Ho channel.

Note that the received data for both the B channel and the Ho channel is sent to the layer 1 control unit 3. Physical path 7. The data is transferred to the memory unit 6 via the layer 2 control unit 4 and the path line 9, and is subjected to protocol processing by the processor 5.

However, when the above control is performed, if some kind of failure occurs in the serial transmission line B1 of the physical path 7, the H including this serial transmission line B1. Use of the channel will no longer be possible.

The present invention has been made with attention to the above points, and provides a communication control device that can establish a data link using the H0 channel even if a failure occurs in a part of the serial transmission line that constitutes the physical path. The purpose is to provide

(Means for Solving the Problems) A communication control device of the present invention is a communication control device that accommodates an ISDN primary group interface, and includes a layer 1 control unit that controls the physical layer of the interface, and a layer 1 control unit that controls the physical layer of the interface, and a layer 1 control unit that controls the physical layer of the interface. Layer 2 that controls the link layer
A physical path connecting the control unit, the layer 1 control unit, and the layer 2 control unit and consisting of a serial transmission path provided as many as the number of channels for low-speed multiplex communication, and a data link establishment for the high-speed communication channel. When there is a fault in the selected serial transmission path, the channel selection section selects one of the serial transmission paths of the physical path, and if there is a fault in the selected serial transmission path, the fault is detected and the channel selection section selects another serial transmission path. The present invention is characterized by comprising a fault detection section that instructs to select a route.

(Operation) In the above device, when there is a fault in the serial transmission path selected by the channel selection section, the fault detection section detects the fault and issues an instruction to select another serial transmission path. That is, the Ha channel is a bundle of six B channels, and the physical path is provided with serial transmission lines corresponding to the six channels. If there is a failure in one of them, the other one is automatically selected and a data link of the H0 channel is established. (Examples) Hereinafter, the present invention will be explained in detail using examples shown in the drawings.

FIG. 1 is a block diagram showing an embodiment of a communication control device of the present invention.

The communication control device l in the figure is similar to that shown in FIG.
It is connected to the SDN network 2. This device has layer 1
A control section 3, a layer 2 control section 4, a processor 5, a memory section 6, and a LAPD control section 8 are provided.

As described above, the layer 1 control unit 3 is a circuit for controlling the physical path of the ink face. Further, the layer 2 control unit 4 is a circuit for controlling the data link layer of the interface. The LAPD control unit 8 is
This circuit manages the transfer of call control information sent and received via the D channel. Processor 5 is a circuit for controlling the operation of the entire device. The memory unit 6 stores the operating program of the processor 5, and during operation, the memory unit 6 stores the operating program of the processor 5.
Used to store channel and H0 channel data.

Here, the layer 1 control section 3 and the layer 2 control section 4 are connected by a physical path 7 including serial transmission lines 81 to B23 corresponding to the number of B channels for low-speed multiplex communication. Furthermore, this physical path 7 is provided with a serial transmission line D for transmitting D-channel signals.

In addition, the layer 2 control unit 4, the processor 5, and the memory unit 6
are interconnected by a pass line 9.

The above configuration is similar to the conventional device shown in FIG. 2, and the specific schematic configuration is the same as the conventional device.

Here, in the communication control device of the present invention, the processor 5 includes:
A failure detection section 11 and a channel selection section 12 are provided.

The failure detection unit 11 is connected to the layer 2 control unit 4 via a failure notification line 13. For example, the failure detection unit 11
This is a circuit that receives a timeout that occurs when operation is interrupted for a certain period of time or a fault notification when an abnormal signal is transmitted through the channel selector 12, and outputs an instruction signal to be described later to the channel selection section 12. The channel selection unit 12 is a circuit that, when a predetermined instruction signal is input from the failure detection unit 11, switches the serial transmission path for which selection has already been notified to the layer 1 control unit 3.

The communication control device 1 of the present invention operates in exactly the same way as the conventional device shown in FIG. 2 described above when establishing a data link for only the B channel.

On the other hand, when establishing a data link for the Ha channel,
For example, the channel selection unit 12 of the processor 5
When using the H0 channel using the B channels from time slot 1 to time slot 6 shown in the figure, the serial transmission line B1 corresponding to the youngest time slot 1 is
Selected for establishing data link of H0 channel.

However, if there is a fault in the serial transmission path B1, the layer 2 control section 4 notifies the fault detection section 11 of the fault via the fault notification line 13. Fault detection unit 1
Upon receiving the notification, channel selection section 1 outputs a predetermined instruction signal to channel selection section l2. Upon receiving the instruction signal, the channel selection section 12 outputs a control signal to the layer 1 control section 3 to select, for example, the serial transmission path B2 instead of the previously selected serial transmission path B1.

This control signal is transmitted to the layer 1 control unit 3 via the control line 10.
is transmitted to. As a result, the layer I control unit 3 uses the failure-free serial transmission path B2. Establish a data link for the channel.

FIG. 4 shows an explanatory diagram of a more specific operation of the apparatus of the present invention.

This operation is mainly performed by the failure detection section 11 and channel selection section 12 of the processor 5 shown in FIG.

First, at the start of operation, it is determined whether the H0 channel will be used (step SL).

Here, if the Ha channel is not used, the process moves to other processing (step S2). That is, if only the B channel is to be used, control is shifted to using the B channel (not shown).

When the Ha channel is used, first, the serial transmission path corresponding to, for example, the lowest numbered time slot is selected in the manner described above (step S3). Here, the failure detection unit 11 shown in FIG. 1 determines whether or not there is a failure in the serial transmission path (step S4).

If there is no failure, a data link is established using the serial transmission path and communication is started (step S5).

On the other hand, if there is a failure, it is determined whether there is another serial transmission path (step S6). That is, for the six B channels constituting the H0 channel, serial transmission lines provided corresponding to each are selected in order, and serial transmission lines with no faults are selected.

In step S7, select the next serial transmission path,
In step S4, it is determined again whether or not there is a failure in the transmission path, and if any of the serial transmission paths is healthy, normal communication is started in step S5. However, if there is a fault in all the serial transmission lines, the process moves from step S6 to step S8, and fault processing is performed.

Fault detection unit 11 and channel selection unit 1 shown in FIG.
2 performs the operations described above to establish a data link of the H0 channel using a healthy serial transmission path.

The present invention is not limited to the above embodiments.

The fault detection section 11 and the channel selection section 12 are not necessarily separate circuits, but may be an integrated circuit.

Furthermore, the failure detection unit 11 detects a failure in the serial transmission path in advance before the operation of the channel selection unit l2 starts, and the channel selection unit 12 informs the layer 1 control unit 3 that the serial transmission path has no failure from the beginning. There is no problem with a configuration in which control is performed to select the .

(Effect of the invention) . The communication control device of the present invention described above uses H for high-speed communication when accommodating an ISDN primary group interface.

When establishing a data link for a channel, a fault-free serial transmission path is selected from among the serial transmission paths for the B channel used for the H0 channel, so any one of the serial transmission paths is healthy. As long as H0
It becomes possible to continue data transmission on the channel.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a communication control device of the present invention, FIG. 2 is a block diagram showing an example of a conventional communication control device, and FIG. 3 is an explanatory diagram of the format of a message sent and received over an ISDN network. FIG. 4 is an operational flowchart of the apparatus of the present invention. l... Communication control device, 2... ISDN network, 3...
Layer 1 control unit, 4... Layer 2 control unit, 5... Processor, 6... Memory unit, 7... Physical path, 8...
...LAPD control unit, 9...pass line, 10...
Control line, 1l...fault detection section, 12...channel selection section, l3...fault notification line. Block diagram of the communication system W device of the present invention Fig. l Block diagram of the conventional overconfidence system W device Fig. 2 Format of messages sent and received in ISDNiJl Fig. 3 Operation flowchart of the device of the present invention Fig. 4

Claims (1)

[Scope of Claims] A communication control device accommodating an ISDN primary group interface, comprising: a layer 1 control unit that controls a physical layer of the interface; a layer 2 control unit that controls a data link layer of the interface; A physical path that connects the layer 1 control unit and the layer 2 control unit and consists of a serial transmission path provided as many as the number of channels for low-speed multiplex communication, and the physical path when establishing a data link for the high-speed communication channel. a channel selection unit that selects one of the serial transmission paths; and a channel selection unit that detects the failure when there is a failure in the selected serial transmission path and instructs the channel selection unit to select another serial transmission path. 1. A communication control device comprising: a fault detection section that gives an instruction.