JPH1023066A - Packet protocol converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly switch a packet network connection interface section by allowing a terminal subscriber interface section to detect stop of a status report from each packet network connection interface section. SOLUTION: Terminal subscriber interface sections 6a, 6b, 6c each consisting of a network layer function section 20 monitor at all times the normality of status reports 21a, 21b, sent from packet network connection interface sections 7a, 7b. On the occurrence of a fault, the packet network connection interface section 7a, 7b are quickly switched.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packet protocol (Packet Protocol) for subscribing to a packet switching network (hereinafter abbreviated as a packet network).
col) conversion device.

[0002]

2. Description of the Related Art FIG.
FIG. 1 is a block diagram illustrating a configuration of a conventional packet protocol conversion device disclosed in Japanese Unexamined Patent Publication (Kokai) No. H10-26095. In FIG. 7, 6a, 6
Reference numerals b and 6c denote terminal subscriber interface sections each having a terminal control function and a function corresponding to a network layer protocol of the packet protocol added to a terminal interface for each non-packet terminal, which will be described later. A packet network connection interface unit for connecting to a packet network having a data link layer protocol and a physical layer protocol among the packet protocols, 8
Is a common input / output bus in which each terminal subscriber interface section 6a, 6b, 6c and a plurality of packet network connection interface sections 7a, 7b are connected in parallel with each other.

FIG. 8 is a block diagram showing connection to a packet network. 8, 1 is a packet network, 2 is a packet terminal (hereinafter abbreviated as PT), 3 is a non-packet terminal without a packet protocol which is a communication protocol in the packet network 1 (hereinafter abbreviated as NPT), 4 is a packet network. It is a protocol conversion device (PAD).

FIG. 9 is a block diagram showing a data transfer operation in this conventional example. In FIG. 9, reference numerals 50 to 55 are logical paths formed on the common input / output bus 8. For example, it is assumed that normally only the packet network connection interface unit 7a is used and the logical paths 50, 51, 52 are configured. If the packet network connection interface unit 7a fails, the terminal subscriber interface units 6a, 6
The network layer function unit 20 in b, 6c detects and determines this state and switches to use the packet network connection interface unit 7b by configuring the logical paths 53, 54, 55.

FIG. 10 is a flowchart showing the logical path switching operation described with reference to FIG. 9, and reference numerals 60 to 65 denote steps. In step 60, for example, the terminal subscriber interface unit 6a packetizes the non-packet communication procedure from the NPT 3 by the network layer function unit 20 (step 60), prepares transfer data to be transferred to the packet network connection interface unit 7a, and sets common data. A bus request signal is output to obtain the right to use the input / output bus 8, and the response is awaited. If the response is NO, step 61 is repeated, and if the response is YES, the process proceeds to step 62 to transfer data to the packet network connection interface unit 7a. When this data transfer is completed, there is a status report from the packet network connection interface unit 7a. If the report is a normal end report, the process proceeds to step 64, but if there is an abnormal end report or a predetermined If there is no status report within the time, the process proceeds to step 65, where the destination address is changed from the packet network connection interface unit 7a to the packet network connection interface unit 7b, and step 61
Return to If the use of the common input / output bus 8 is permitted, the determination in step 61 is YES, and the data transfer in step 62 is performed. The destination of this data transfer is step 65
Is switched to the packet network connection interface 7b, the transferred data is input to the packet network connection interface unit 7b. If the packet network connection interface 7b is operating normally and the status report of the normal end is returned, step 63 is executed. Is YES. The operation in the terminal subscriber interface units 6b and 6c is the same.

In the example shown in FIG. 7, the PAD of the dual system backup has been described with two packet network connection interfaces 7a and 7b, but in the normal state, for example, the logical paths 51, 52 and 55 are configured. Then, the packet network connection interface units 7a and 7b may be operated together so that the logical paths 51 and 52 are switched to the logical paths 53 and 54 when the packet network connection interface unit 7a fails. In addition, three or more packet network connection interface units may be connected to a common input / output bus.

Next, the operation will be described with reference to FIGS. 7 and 9. Terminal subscriber interface units 6a, 6b, 6c
And the packet network connection interface units 7a and 7b are connected in parallel with each other to a common input / output bus 8, and which of the terminal subscriber interface units 6a, 6b and 6c and the packet network connection interface units 7a and 7b are connected. Data transfer is also possible in the combination. Normally, only the packet network connection interface unit 7a is used, and the logical paths 50, 51, and 52 are configured. When the packet network connection interface unit 7a fails, the network layer function unit 20 in the terminal subscriber interface unit 6a, 6b, 6c is switched to the packet network connection interface unit 7a.
The data transfer is performed to a, and the status is reported as abnormal termination, or when there is no status report within a predetermined time, it is recognized as abnormal and the logical paths 53, 54, and 55 are switched to use the packet network connection interface 7b. .

[0008]

In the conventional packet protocol conversion device, a status report after transferring data from the terminal subscriber interface unit to the packet network connection interface unit, or an abnormality in the packet network connection interface unit due to no response. Has a problem that it takes a long time to detect an abnormality since the packet communication is detected, and the packet communication is cut off because the switching of the packet network connection interface unit in the packet protocol converter is performed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and promptly switches from an abnormal packet network connection interface unit to a normal packet network connection interface unit to perform packet communication with a partner terminal. It is an object of the present invention to provide a packet protocol conversion device capable of continuing the above.

[0010]

In the packet protocol converter according to the first aspect of the present invention, for example, an abnormal stop due to no status report is detected by the packet network connection interface unit 7a, and the packet network connection interface unit 7a The terminal subscriber interface units 6a, 6b and 6c are provided for switching from the network interface to another packet network connection interface unit 7b.

In the packet protocol converter according to the second aspect of the present invention, for example, when an abnormal condition is detected in the packet network connection interface unit 7a, if the connection is a partner selection connection, the packet protocol conversion device communicates with the partner terminal via the normal packet network connection interface unit 7b. And a terminal subscriber interface unit 6 for making a call setting and continuing packet communication.

In the packet protocol conversion device according to the third aspect of the present invention, for example, when the packet network connection interface unit 7a detects that the connection is fixed, the table of the communication partner is transmitted to the normal packet network connection interface unit 7b. Terminal subscriber interface units 6a, 6b, 6c for performing packet communication by switching.
It has.

In the packet protocol converter according to the fourth aspect of the present invention, the terminal subscriber switches the physical line with the packet network 1 in conjunction with the abnormality of the dual network interface units 7a and 7b. An interface unit 6 is provided.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the packet protocol converter according to the first embodiment.
1, components corresponding to those shown in FIG. 7 are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 1, reference numerals 21a and 21b denote status reports issued from the packet network connection interface units 7a and 7b.
b has stopped.

Next, the operation of the first embodiment will be described with reference to the flowchart of FIG. FIG. 2 is a flowchart showing the switching process of the packet network connection interface units 7a and 7b shown in FIG. 1, and 70 to 74 represent each step. Terminal subscriber interface units 6a, 6
b, 6c are always packet network connection interface units 7a,
The normality of the packet network connection interface units 7a and 7b is monitored by the status reports 21a and 21b of the 7b. If the currently connected packet network connection interface unit is the packet network connection interface unit 7a, the status report from the packet network connection interface unit 7a is step 70, and if this is YES, the process proceeds to step 71, The line is connected by the connection interface 7a. If NO, the process proceeds to step 72, where the presence or absence of a status report is confirmed by the packet network connection interface unit 7b. In step 72, as in the case of step 70, if YES, the flow advances to step 73 to connect a line with the packet network connection interface 7b. If NO, the packet network connection interface units 7a and 7b are both in a stopped state, and the apparatus is stopped in step 74.

As described above, according to the first embodiment, in the duplex system of the packet network connection interface unit, an abnormality of the packet network connection interface unit can be detected and switching can be performed promptly, and packet communication is continued. There is an effect that can be.

Embodiment 2 FIG. Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. FIG. 3 shows the second embodiment.
1 is a block diagram illustrating a configuration of a packet protocol conversion device according to the first embodiment. 3, reference numeral 6 denotes a terminal subscriber interface unit 7a, 7b denotes a packet network connection interface unit,
Reference numeral 8 denotes an input / output bus for connecting the terminal subscriber interface unit 6 to the packet network connection interface units 7a and 7b.
Is a packet network, 2 is a packet terminal (PT), and 3 is a non-packet terminal (NPT).

Next, the operation of the second embodiment will be described with reference to FIG.
A description will be given based on the flowchart of FIG. In step 80, the status report is lost from the packet network connection interface 7a. In step 82, when there is a status report from the packet network connection interface 7b, in step 83, the packet is The data transfer route is switched to the network connection interface 7b. In step 84, data transfer is restricted for the NPT 3 until the call setting with the packet network connection interface 7b is completed (step 87). In step 85, the terminal subscriber interface unit 6 transmits a CR packet to the packet switching network 1 via the transfer route switched in step 83 to the PT2. In step 86, when the PT2 returns a CC packet to the CR packet transmitted from the terminal subscriber interface unit 6 and the terminal subscriber interface unit 6 receives the CC packet, the call setting is completed. If there is a status report from the packet network connection interface unit 7a in step 80, the process proceeds to step 81, where the packet network connection interface unit 7a is used. Also, the packet network connection interface units 7a, 7b
If there is no status report from both, the device is shut down at step 88.

As described above, according to the second embodiment, even if the switching of the packet network connection interface unit is performed in the packet protocol converter, the packet communication can be continued without disconnecting the call. is there.

Embodiment 3 Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. FIG. 5 shows the third embodiment.
1 is a block diagram illustrating a configuration of a packet protocol conversion device according to the first embodiment. In the third embodiment, the function of the other party's selection connection (VC) in the second embodiment is replaced with the other party's fixed connection (P
VC). VC is an abbreviation for virtual circuit, and PVC is an abbreviation for permanent virtual circuit, which is widely used in public networks. In FIG. 5, reference numeral 22a in the network layer function unit 20 provided in each of the terminal subscriber interface units 6a, 6b, and 6c denotes a PVC table for the packet network connection interface unit 7a;
Is a PVC table for the packet network connection interface unit 7b. The PVC function omits call setting in the VC function. That is, in the PVC function, a route to the partner terminal is set in advance in order to omit the call setting exchange with the partner terminal such as CR transmission and CC reception in steps 85 and 86 in FIG. ing.
When the packet network connection interface units 7a and 7b are switched, the PVC tables 22a and 22b are changed respectively.

As described above, according to the third embodiment, similarly to the effect of the second embodiment, even if the packet network connection interface is switched in the packet protocol converter, the packet communication is performed without disconnecting the call. There is an effect that can be continued.

Embodiment 4 Hereinafter, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 6 shows the fourth embodiment.
1 is a block diagram illustrating a configuration of a packet protocol conversion device according to the first embodiment. 6, components corresponding to the components shown in FIG. 3 are given the same reference numerals, and descriptions thereof will be omitted.
In FIG. 6, reference numeral 23 denotes a line by the terminal subscriber interface unit 6 having means for switching a line (physical line) with the packet network 1 in response to an abnormality of the dual packet network connection interface units 7a and 7b. This is a line switching device for switching. The line switch 23 is used to make a dual line a single line, and simultaneously switches the line in conjunction with a change in the PVC table. Thereby, the number of connection lines with the packet network 1 can be reduced. For example, when a failure of the packet network connection interface 7a is detected by the terminal subscriber interface 6,
At the same time as switching the VC table to the normal packet network connection interface unit 7b, the line switching unit 23 switches the packet table to the normal packet network connection interface unit 7b.
Connect the line.

As described above, according to the fourth embodiment, the provision of the line switch 23 has an effect that the number of lines connected to the packet network 1 can be reduced.

[0024]

As described above, according to the first aspect of the present invention, the terminal subscriber interface unit stops the status report from each packet network connection interface unit due to the abnormality of the packet network connection interface unit (stops at the time of abnormality). Is configured so that the packet network connection interface is switched to the normal packet network connection interface from the abnormal packet network connection interface, so that packet communication with the partner terminal can be performed. The effect of being able to continue is obtained.

According to the second aspect of the present invention, when the terminal subscriber interface unit detects an abnormality of the packet network connection interface unit, the terminal subscriber interface unit performs normal packet network connection if it is a partner selection connection (VC). Since packet communication is continued by setting up a call with the partner terminal via the interface unit, packet communication must be continued without disconnecting the call even if the packet network connection interface unit is switched. Is obtained.

According to the third aspect of the present invention, when the terminal subscriber interface unit detects an abnormality in the packet network connection interface unit, the terminal subscriber interface unit performs normal packet network connection if it is a permanent connection (PVC). Since the packet communication is continued by switching the communication partner table (PVC table) to the interface unit, the packet communication can be performed without disconnecting the call even if the packet network connection interface unit is switched. The effect of being able to continue is obtained.

According to the fourth aspect of the present invention, since the terminal subscriber interface unit is configured to switch the physical line with the packet network in conjunction with the abnormality of the packet network connection interface unit having the dual system, The effect that the number of connection lines with the packet network can be reduced and packet communication can be continued can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a packet protocol conversion device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a packet protocol conversion device according to a second embodiment of the present invention.

FIG. 4 is a flowchart showing the operation of the second embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a packet protocol conversion device according to Embodiment 3 of the present invention.

FIG. 6 is a block diagram showing a configuration of a packet protocol conversion device according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a conventional packet protocol conversion device.

FIG. 8 is a block diagram showing connection of a conventional packet protocol converter to a packet network.

FIG. 9 is a block diagram showing a data transfer operation in a conventional packet protocol converter.

FIG. 10 is a flowchart showing the operation of a conventional packet protocol conversion device.

[Explanation of symbols]

1 packet network, 2 packet terminal, 3 non-packet terminal, 6a, 6b, 6c, 6 terminal subscriber interface unit, 7a, 7b packet network connection interface unit,
8 input / output bus, 20 network layer function part, 21
a, 21b Status report, 22a, 22b table, 23 Line switch.

Claims (4)

[Claims] 1. A packet protocol conversion device for converting between a communication protocol and a packet protocol for a packet terminal to join a packet switching network, comprising a data link layer protocol and a physical layer protocol among the packet protocols. A packet network connection interface unit for connecting to the packet conversion network, and detecting an abnormal stop due to no status report from the packet network connection interface unit, and from the packet network connection interface unit to another packet network connection interface unit And a terminal subscriber interface unit having means for switching the packet protocol. 2. A packet protocol conversion device for converting between a communication protocol and a packet protocol for a packet terminal to join a packet switching network, comprising a data link layer protocol and a physical layer protocol among the packet protocols. A packet network connection interface unit for connecting to the packet conversion network, and a call to a partner terminal via a normal packet network connection interface unit if a connection is selected when a failure is detected in the packet network connection interface unit. A packet protocol conversion device, comprising: a terminal subscriber interface unit having means for performing setting and continuing packet communication. 3. A packet protocol conversion apparatus for converting between a communication protocol and a packet protocol for a packet terminal to join a packet switching network, comprising a data link layer protocol and a physical layer protocol among the packet protocols. A packet network connection interface unit for connecting to the packet conversion network, and a table of a communication partner is switched to a normal packet network connection interface unit if the other party is a fixed connection when an abnormality of the packet network connection interface unit is detected. And a terminal subscriber interface unit having means for continuing packet communication. 4. A packet protocol conversion device for converting between a communication protocol and a packet protocol for a packet terminal to join a packet switching network, comprising a data link layer protocol and a physical layer protocol among the packet protocols. A terminal joining unit having a packet network connection interface unit for connecting to the packet conversion network, and means for switching a physical line with the packet switching network in response to an abnormality of at least a duplicated packet network connection interface unit; A packet protocol conversion device comprising a user interface unit.