JPH0522348A - Relay system for connecting packet exchange networks - Google Patents

Abstract

PURPOSE:To continue communication by executing packet bypass processing without interruption of a call during communication when any fault takes place between half gateways in a communication network in which plural packet exchange networks with different architecture are interconnected at a multi- point. CONSTITUTION:When a call is sent from a terminal equipment 3a of an exchange network 1a to a terminal equipment 3b of an exchange network 1b, one call 6a is sent in a path of terminal equipment 3a-exchange network 1a - half gateway 2a - relay line 4a - half gateway 2b exchange network 1b - terminal equipment 3b. Simultaneously, a standby call 6b is sent between a virtual terminal equipment 5a accommodated in the half gateway 2a and a virtual terminal equipment 5b accommodated in the half gateway 2b in the route of virtual terminal equipment 5a - half gateway 2a - exchange network 1a - half gateway 2c - relay line 4c - half gateway 2d - exchange network 1b - half gateway 2b - virtual terminal equipment 5b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relay system for connection between packet switching networks, and more particularly, to a plurality of X. 7
X.5 between half gateways in a half gateway in a communication network in which multiple points are connected by a half gateway of the inter-network protocol specifications. The present invention relates to a packet detour system when a 75 trunk line fails.

[0002]

2. Description of the Related Art Conventionally, in order to connect a plurality of different types of packet switching networks, for example, a half gateway as shown in FIG. 3 is used, and the accommodating terminal 3a of the packet switching network 1a.
The routes used between the accommodating terminals 3b of the packet switching network 1b are terminal 3a-packet switching network 1a-half gateway 2a-relay line 4a-half gateway 2b-packet switching network 1b-terminal 3b and terminal 3a. -Packet switching network 1a-Half gateway 2c-Relay line 4b
There are two routes: the half gateway 2d, the packet switching network 1b, and the terminal 3b.

Next, the operation will be described. In the packet transmission from the terminal 3a to the terminal 3b, the shortest route is usually used: the route of the terminal 3a-packet switching network 1a-half gateway 2a-relay line 4a-half gateway 2b-packet switching network 1b-terminal 3b. It The two terminals are connected to each other via the relay line 4a during communication between different packet networks on the above route.
If he falls into a disability, X. 75 Due to the nature of the inter-network protocol, the call route between different packet networks cannot be changed from the time of call connection to the time of call disconnection, so when a call between two terminals is disconnected and re-connected, the terminal 3a-packet exchange is performed. Communication was restarted by a call on the route of network 1a-half gateway 2c-relay line 4b-half gateway 2d-packet switching network 2b-terminal 3b.

[0004]

As described above, the different types of packet switching networks can be connected to the X. In the case of connection using the 75 inter-network protocol, they are connected by a half gateway, and communication between terminals accommodated in different packet switching networks is always performed via the half gateway. If a failure occurs in the relay path between the half gateways during communication between terminals accommodated in different types of packet switching networks, the call using the failed relay path becomes X. Due to the nature of the 75 inter-network connection protocol, the call route cannot be changed from call connection to call disconnection.
You will be disconnected regardless of whether there is a bypass.

That is, if the call that has become incapable of communication at the time of the failure is a VC (Virtual Call), the call is disconnected, and if the call connection is made again during the failure, a relay path between the other half gateways. The call is re-established on the detour route using, but it is PVC (Perma
If it is a "nent Virtual Circuit", the PVC is not disconnected and the PVC route for communication between heterogeneous packet switching networks is decided from the beginning. Therefore, there is a problem that communication cannot be performed in the PVC until the failure is recovered.

The present invention has been made in order to solve the above-mentioned problems, and a relay path failure occurs between the half gateways which are being used by the existing communication while the terminals accommodated in different packet switching networks are communicating. In this case, for a call that can be communicated through a route using another normal relay route, communication is continued through a route different from the original route using the normal relay route in the gateway without disconnecting the existing call. It is an object of the present invention to obtain a packet-switching inter-network connection relay system that is capable.

[0007]

SUMMARY OF THE INVENTION A connection relay system between packet switching networks according to the present invention uses a plurality of packet switching networks having different architectures for X. In the communication network connected by the inter-network protocol gateway, the X.75 between the half gateways used by the call being communicated. When the packet transmission between the half gateways becomes impossible due to some failure on the 75 trunk line, another normal X. The feature of the present invention is that communication can be continued by a route different from the original one using a 75 gateway and a normal gateway connecting half gateway.

[0008]

In the packet switching inter-network connection relay method according to the present invention, when a failure occurs in the trunk line between the half gateways during call communication, the half gateways use a spare call to transfer the packet. Then, each half gateway and the packet switching network send and receive packets as if the trunk line between the half gateways is normal, regardless of VC or PVC, without disconnecting the call in use. The packet transfer process is performed through another route and the communication between the terminals is continued.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an embodiment showing a call route between heterogeneous packet networks, and FIG. 2 is a table showing an original call using a spare call in a half gateway showing an embodiment of the present invention. Is shown. When different types of packet networks are connected by the half gateways 2a, 2b, 2c, 2d as shown in FIG. 1, when communication is performed between the terminal 3a and the terminal 3b, the terminal 3a-packet switching network 1a-half gateway 2a-relay At the same time as one call 6a is placed on the route of line 4a-half gateway 2b-packet switching network 1b-terminal 3b, virtual terminal 5 under the half gateway 2a.
Between the virtual terminal 5a and the virtual terminal 5b, the virtual terminal 5a-half gateway 2a-packet switching network 1a-half gateway 2c
-The relay line 4b-the half gateway 2d-the packet switching network 1b-the half gateway 2b-the virtual terminal 5b is set up as a backup call 6b.

Normally, the call between the terminal 3a and the terminal 3b is performed by the call 6
However, when a failure occurs in the trunk line 4a between the half gateways 2a and 2b, the backup call is used to transfer the packet from the half gateway 2a to 2b or from the half gateway 2b to 2a. Perform processing.

The packet from the terminal 3a to the terminal 3b after the occurrence of the failure is sent to the terminal 3a and the packet switching network 1a as in the normal state.
It reaches the half gateway 2a via the relay line 4
Half gateway 2a calls call 6b because a is a failure.
To use the virtual terminal 5a between the virtual terminals 5a and 5b.
a-half gateway 2a-packet switching network 1a-half gateway 2c-relay line 4b-half gateway 2d-packet switching network 1b-half gateway 2b
-Half gateway 2 through the route of virtual terminal 5b
Transfer the packet from a to 2b.

At the half gateway 2b, the terminal 3b receives the call as if it was transferred through the route of the call 6a.
To the packet switching network 1b and the terminal 3b. Since the packet network does not recognize that the relay line 4a is a failure, it does not disconnect the call even if it is a VC, and it is possible to send and receive packets even if the PVC is supposed to be incapable of communication due to a detour. The communication continues.

The backup call between the virtual terminal 5a accommodating the half gateway 2a and the virtual terminal 5b accommodating the half gateway 2b is performed between the terminals accommodating the packet switching network 1a and the terminals accommodating the packet switching network 1b through the trunk line 4a. If one call is placed for each call, the packet transfer using the standby call is possible in all calls between the terminals accommodated in the packet switching network 1a and the terminals accommodated in the packet switching network 1b passing through the trunk line 4a.

In the case where the auxiliary call path is in failure during packet transfer in the auxiliary call, it is necessary to disconnect the call during normal times. Therefore, regarding communication using the auxiliary call in each half gateway Information is stored in a table as shown in FIG. 2 for the spare call and the communication in use. This information is also referred to when the call route used during normal operation becomes normal at the time of failure recovery and packet transfer using a spare call is no longer necessary, and when switching back to the normal communication route. In each half gateway, the call status between the half gateways needs to be sequentially written in the table shown in FIG. 2 when the call status changes.

Since the above-mentioned half gateway does not notify the packet switching network of a failure in the relay line between the half gateways, the packet switching network may request a call connection to be newly used as a failure relay path. The half gateway rejects the connection, selects another detour route in the packet switching network, and makes a call. Further, when all the spare calls are disconnected, the packet switching network is notified that the own half gateway cannot be used.

[0016]

As described above, according to the present invention, when a failure occurs in the trunk line between the half gateways, the spare call is used to disconnect the currently used call between the half gateways. By carrying out the packet transfer processing in the above, the communication of the VC does not require the processing such as disconnection and re-call connection at the time of failure, and the route is decided from the beginning and the detour at the time of failure should be impossible. Even communication can be continued.

[Brief description of drawings]

FIG. 1 is a connection diagram showing a call route between heterogeneous packet networks according to the present invention.

FIG. 2 is an explanatory diagram showing a table that a half gateway according to the present invention needs to have.

FIG. 3 is a connection diagram of a heterogeneous packet switching network using a conventional half gateway.

[Explanation of symbols]

 1 packet switching network 2 half gateway 3 packet terminal 4 X. 75 trunk line 5 virtual terminal 6 call route

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[Procedure amendment]

[Submission date] October 9, 1991

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

The present invention has been made in order to solve the above-mentioned problems, and a relay path failure occurs between the half gateways which are being used by the existing communication while the terminals accommodated in different packet switching networks are communicating. In this case, for a call that can be communicated through a route using another normal relay route, the communication is continued by a route different from the original route using the normal relay route in the gateway without disconnecting the call. It is an object of the present invention to obtain a packet-switching inter-network connection relay system that is capable.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

[0008]

In the relay system for connection between packet-switched networks according to the present invention, when a failure occurs in the trunk line between the half gateways during call communication , the other half gateways are not connected to each other.
Performs packet transfer using call preliminary strung normal relay line of, if each of the half gateways and a packet switching network as if the trunk is normal between the half gateways transmit and receive packets Done, VC, P
Regardless of the VC, the packet transfer process is performed through a route different from the original route without disconnecting the call in use, and the communication between the terminals is continued.

Claims (1)

Claims: What is claimed is: 1. A plurality of packet switching networks having different architectures are connected to each other at a multipoint. In the communication network connected by the inter-network protocol gateway, the X.75 between the half gateways used by the call being communicated. When the packet transmission between the half gateways becomes impossible due to some failure on the 75 trunk line, another normal X.
75 relay line and normal relay line connection A packet switching inter-network connection relay system that enables continuation of communication by a route different from the original one using a half gateway.