JPH07273793A - Packet switching device - Google Patents

Abstract

PURPOSE:To easily manage the set information content for a transit route between outgoing and incoming switching devices without increasing it by defin ing a transit route between outgoing and incoming switching devices by continu ous connection of a transit route between adjacent switching devices and a transit route between outgoing and incoming switching devices. CONSTITUTION:When a packet is repeated from a packet switching device 1 to a packet switching device 4, a transit route between the outgoing and incoming switching devices (SDROT) 15 to the device 4 recognizes it as a transit route (ROT) 6 between the adjacent switching device of a transit line 6. The recognition number is stored in the ROT information area of an outgoing packet and is set to the transit line 6. A switching device 2 which accepts the packet recognizes the correspondence of the ROT 12 to the SDROT 20 for the device 4, rewrites the ROT information area and transmit it to a transit line 10. The transit switching device repeats the similar operation and repeats the packet to the address device 4. The connection of the transit line 6 to ROT 12 to device 2 to SDROT 20 is the SDROT structure information. Thus, the information to be managed can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packet switching network composed of a plurality of packet switching devices interconnected by trunk lines.

[0002]

2. Description of the Related Art A conventional packet switching apparatus has realized a relay method as disclosed in, for example, Japanese Patent Laid-Open No. 1-196940. In this method, a logical relay path is set in advance between the packet transmission switching device and the packet receiving switching device. That is, for example, as shown in FIG. 11, a logical relay route (ROT) between adjacent switching devices is defined on the relay lines 6 to 11 between the adjacent switching devices 1 to 5, and the originating switching device connects the ROT to the relay switching device. A logical relay route to the destination switching device is set, and the logical relay route between the originating and destination switching devices (S
DROT). For example, in FIG. 11, the SDROT addressed to the switching devices 1 to 4 is the ROT 12 on the trunk line 6,
By connecting the ROT 16 on the trunk line 10 from the switching device 2 and the ROT 17 on the trunk line 11 from the switching device 5, SDR
It is set as OT26. The originating exchange apparatus 1 uses the SDROT configuration table for the exchange apparatus 4 as shown in FIG.
T26 and ROT12 on the trunk line 6 are associated with each other, and the switching device 2 receives the incoming RO corresponding to the incoming trunk line 6 as shown in FIG.
ROT 12 on the trunk line 6 entered by the T-out ROT correspondence table
The switching device 5 associates the ROT 16 on the outgoing trunk line 10 with the incoming RO line corresponding to the incoming trunk line 10 as shown in FIG.
According to the T-out ROT correspondence table, ROT1 on the incoming trunk line 10
6 and the ROT 17 on the outgoing relay line 11 are associated with each other. Such an SDROT is set in advance for each set of originating and terminating switching devices when constructing a network, and each switching device outputs a packet from an incoming trunk line based on a predetermined incoming ROT-outgoing ROT correspondence table of each ROT. Transfer to a relay line for relay.

[0003]

In the packet switching device having such a packet relay method, as the configuration information of the preset SDROT, the source switching device number, the trunk line number and the ROT number, the relay switching device number, for each SDROT, Although it is necessary to store information such as the destination switching device number together with its connection relation, the SDROT that can be set greatly increases as the shape of the network becomes complicated.
SROT is defined by the connection between the ROT between the originating and terminating exchanges and the transit exchange, and the SOT passes through the SOT by the connection between the ROT between the originating and terminating exchanges and the transit exchange.
There is a problem that when the failure occurs in the network because the originating and terminating switching equipment of the DROT is not recognized, the detour by switching the relay route cannot be performed unless the originating and switching equipment is notified of this. Further, when such an SDROT is newly set in the network, an appropriate relay line from the source switching device to the destination switching device, an unused ROT on it and a connection of the relay switching device are found and set as a new SDROT. There is a problem that the operation is necessary and the setting method is complicated.

The present invention has been made to solve the above problems, and manages the SDROT setting information amount that each switching device should have without significantly increasing even if the network shape becomes complicated. It is an object of the present invention to provide a packet switching device that realizes a packet relay method that facilitates the detouring and facilitates the detouring operation when a network failure occurs. Also,
An object of the present invention is to provide a packet switching device that can automate the setting operation when setting a new SDROT in the network.

[0005]

In a packet switching device according to the present invention, the SDROT between the packet switching devices is the ROT from the originating packet switching device to the packet switching device adjacent to the originating packet switching device and the adjacency. It is constituted by means for relaying a packet defined by the connection from the packet switching device to the destination switching device and SDROT. Also,
A packet switching device according to the present invention is a packet switching device or a packet switching device that has detected a failure when a failure occurs in the trunk line, and the SDROT from the failure detection packet switching device is disabled due to the failure. It is configured by means for replacing the available SDROT for the same destination packet switching device. Further, the packet switching device according to the present invention has an unused R on the trunk line between the own packet switching device and another packet switching device adjacent to the packet switching device in the own packet switching device.
A new SDRO addressed to any other packet switching device
The reserved RO reserved for the T setting and the reserved RO for the new SDROT setting to the adjacent packet switching device.
When a SDROT setting message packet having a T number and the destination packet switching device number is transmitted and a response packet to the SDROT setting message packet is received from the adjacent packet switching device, the new SDROT is addressed to the destination packet switching device. SDRO
Means for additionally setting as T, and the SDROT from the packet switching device adjacent to the own packet switching device.
When the setting message packet is received, the incoming trunk line number at which the message packet is received, the ROT number and the destination packet switching device number which are the contents of the message packet are recognized, and from the own packet switching device addressed to the destination packet switching device. One SDROT is secured, the ROT on the incoming trunk line is stored in association with the secured SDROT from the own packet switching device, and a response packet is sent to the adjacent packet switching device that transmitted the SDROT setting message packet. It is composed of means for returning. Further, the packet switching device according to the present invention is
A means for sending an SDROT setting instruction message packet containing an instruction to newly set an SDROT addressed to another switching device via the own packet switching device, and the own packet switching device Upon receiving the SDROT setting instruction message packet from the device, means for performing the new SDROT setting by using an unused ROT on the incoming trunk line that received the message packet.

[0006]

The packet switching device according to the present invention has an SDR
ROT from the originating exchange device and S from the adjacent exchange device
By defining with DROT, S as the whole network is defined.
The amount of DROT configuration information is reduced, and when a network failure occurs, the relay switching device that detects the failure autonomously performs SDROT.
Can be changed to realize a quick detour operation. Furthermore, when setting a new SDROT, the setting procedure can be performed and set only with the adjacent packet switching device. The packet switching device according to the present invention is such that the packet switching device originating at the time of packet transmission sends the SDROT corresponding to the destination.
To relay the packet to the adjacent exchange device, and from the adjacent exchange device to relay using the SDROT from the adjacent exchange device corresponding to the SDROT. Further, in the packet switching device according to the present invention, when a failure occurs, the SDROT that disables the packet switching device that has detected the failure is replaced with another available SDROT for the same destination packet switching device. Further, the packet switching device according to the present invention exchanges the SDROT setting message / response message with the adjacent packet switching device and thereby the ROT between the own packet switching device and the adjacent packet switching device and the SDROT from the adjacent packet switching device. A new SDROT is set by associating with. Further, the packet switching device according to the present invention is capable of performing the S
A DROT setting instruction message is sent to cause the adjacent switching device to set a new SDROT via the own switching device.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a packet switching network configured by a packet switching device according to an embodiment of the present invention.
5 is a packet switching apparatus of the present invention, and 6 to 8 are packet switching apparatuses (1) and (2), (1) and (3), (2) and (4), (3) and (4), (2). ) And (5) and between (5) and (4), respectively, relay lines, 12, 1
3 is an RO to the adjacent packet switching devices (2) and (3) assigned to the packet switching device (4) on the trunk lines (6) and (7) from the packet switching device (1), respectively.
Similarly, T, 14, 16 are adjacent packet switching devices (4), (5) assigned to the packet switching device (4) on the trunk lines (8), (10) from the packet switching device (2).
To the adjacent packet switching device (4) assigned to the packet switching device (4) on the trunk line (9) from the packet switching device (3).
Is also a trunk line (11) from the packet switching device (5)
It is the ROT to the adjacent packet switching device (4) assigned to the above packet switching device (4). 21, 22,
27 are packet switching devices (2), (3),
SDRO consisting of only one ROT (14), (15), (17) destined to the packet switching device (4) from (5)
T. 20 is the ROT (1
6) is the SDROT addressed to the packet switching devices (2) to (4) defined by the concatenation of SRDOT (27) with SRDOT (27).
18 is the ROT (12) and SD addressed to the packet switching device (2)
Packet switching device (1) to SDROT addressed to (4) defined by connection with ROT (20), 19 is packet switching defined by connection between ROT (13) and SDROT (22) addressed to packet switching device (3) SDROT addressed to devices (1) to (4).

Which SDROT is used by the outgoing packet when the packet is relayed to the packet switching devices 1 to 4 is assigned to each call in advance when the call is set up. In each packet switching device in the network, as shown in FIG. 2, SDROT from the switching device indicates which relay line which R
It has an SDROT configuration table for each destination packet switching device showing whether it is associated with OT. Further, the packet relayed in the network has an ROT information area as information for relaying in the network as illustrated in FIG. 3, and the ROT identification number from the originating / switching device of the SDROT used by the packet is stored therein. To do. For example, for an outgoing packet addressed to the packet switching device 4, the SDR addressed to the switching device 4 illustrated in FIG.
The ROT to be stored is recognized from the OT configuration table. That is, the SDROT 15 addressed to the switching device 4 in the figure is the RO of the trunk line 6.
Since it is known to be T9, this identification number is stored in the ROT information area of the outgoing packet and sent to the trunk line 6. Next, when the switching device 2 receives the packet in which the identification number of the ROT 9 is stored from the trunk line 6, the incoming relay line 6ROT-SDROT correspondence table illustrated in FIG. 4 (this correspondence table shows each switching device for each incoming trunk line). It is recognized that the ROT 12 is associated with the SDROT 20 addressed to the exchange device 4. Next, as illustrated in FIG. 5, the outgoing trunk line number and the ROT number forming the SDROT 20 are known from the SDROT configuration table for the switching device 4 in the switching device 2 similar to that of FIG. 2, so that this ROT identification number (ROT16 in the embodiment). ) Is stored by rewriting the ROT information area of the received packet and storing the outgoing relay line (in the embodiment, the relay line 1
0). Thereafter, the same relay operation is repeated in each relay switching device to relay the packet to the destination switching device 4. By the above operation, each of the packet switching devices 1 to 4 can relay the packet by the relay processing having the same content as that of the conventional one, while the SDROT configuration information amount to be held in the entire network is the relay line 6 in the conventional example. -ROT12-relay switching device 2-relay line 10-ROT16-switching device 5-relay line 11-SDROT of ROT17 The connection of all the constituent elements from the switching device to the destination switching device is SDROT configuration information In the present invention, the connection of the relay line 6-ROT 12-relay switching apparatus 2-SDROT 20 is SDROT configuration information, and therefore there is little information to be managed.

Next, the operation when a failure occurs in the packet switching network shown in FIG. 1 and the switching device 2 detects this will be described with reference to FIG. When the switching device 2 detects a failure of the trunk line 10, the SDR from the switching device 2 becomes a failure due to the failure.
Examine the OT. Regarding SDROT addressed to switching device 4 FIG.
In this embodiment, the corresponding SDROT 20 is disabled. Next, the switching device 2 sends the SDROT 20 to the same switching device 4 for normal S for the contents of all SDROT configuration tables.
Replace with DROT21. As a result, the SDROT 18 from the exchange 1 is the same as the exchange 1 to the ROT 12, but the route from the exchange 2 is the ROT on the trunk line 8.
It is changed to SDROT21 constituted by 14. As described above, the exchange apparatus 1 can continue the normal operation without being aware that the path of the SDROT 15 is changed in the exchange apparatus 2.

Further, the SDROT in the above-mentioned relay exchange device
The switching operation can be used not only when a failure occurs but also for load distribution of each SDROT or congestion control. That is,
In FIG. 1, SDROT from switching device 2 to switching device 4
If 20 is associated with another SDROT in addition to the SDROT 18 from the switching device 1, and the traffic volume of the SDROT 18 becomes abnormally high, for example, the SDROT 18 from the switching device 1 can be changed in the same manner as the switching at the time of failure.
Switch to connect to SDROT21 and SDRO
It is possible to control to reduce the traffic volume of T20.

Further, an embodiment in the case of newly setting SDROT in the packet switching network constituted by the packet switching device according to the present invention will be described with reference to FIG. now,
It is assumed that a new trunk line 23 is added between the packet switching devices 2 and 3 in the packet switching network illustrated in FIG. 1 to form a packet switching network configuration as shown in FIG. Exchange device 3
As shown in FIG. 1, the SDROTs addressed to 4 to 4 already exist in the SDROT 22 composed of the ROT 15 on the trunk line 9.
When T is newly set, it operates as follows.
When the switching device 3 sets a new SDROT addressed to 4 using the relay line 23, the ROT 24 on the relay line 23 is set as a new SDROT 25 addressed to 4 and the switching device 3 has the switching as shown in FIG. Store in the SDROT configuration table addressed to device 4. Next, an SDROT setting message packet indicating that the SDROT 25 addressed to the switching device 4 is newly set by using the ROT 24 on the trunk line 23 is sent to the switching device 2 (this SDROT setting message packet itself is addressed to the switching device 3 origin 2). Relayed using existing SDROT). FIG. 8 shows a schematic structure of this SDROT setting message packet. The contents are a message identification information area indicating that it is a SDROT setting message, a ROT number storage area, a SDROT number storage area, a destination exchange apparatus number storage area of SDROT, etc. Consists of. Upon receiving the SDROT setting message packet from the switching device 3, the packet switching device 2 selects the SDROT 21 addressed to the switching device 4 originating from its own switching device based on the destination switching device number in the packet, and selects the message packet receiving trunk line number. The ROT number (ROT24) in the packet and the SDROT 21 are associated with each other in the ROT-SDROT correspondence table corresponding to the incoming relay line 23 of the switching device 2 as illustrated in FIG. Then, the switching device 2 sends a response packet to 3. The switching device 3, which has received the response packet, determines the SDROT 25 by the ROT 24 on the relay line 23 set previously. A new SDROT is set by the above operation. However, when the procedure for setting a new SDROT from the adjacent exchange device is continuously performed using this new SDROT, for example, in the above embodiment, SDR in the switching device 3
After the setting of the OT 25 is confirmed, the SDROT setting instruction message packet is sent to the adjacent exchange 1. SDROT
The content of the setting instruction message packet is an area for storing the destination exchange apparatus 4 number of the SDROT 25 set by the exchange apparatus 3 as illustrated in FIG. Upon receiving this SDROT setting instruction message packet, the switching device 1 knows from the contents of the packet that a new SDROT addressed to the switching devices 3 to 4 has been set, and the new switching device 4 from the switching device 1 via the switching device 3 The destination SDROT setting is performed on the exchange device 3. As described above, according to the present invention, when a new SDROT is set, it can be carried out only by exchanging data with the adjacent exchange device, and each ROT from the source exchange device to the destination exchange device via the relay exchange device as in the prior art. It is not necessary to perform the procedure for setting the correspondence of each exchange device.

[0012]

As described above, according to the present invention, the SDR
Since the OT is defined by connecting the ROT from the originating switching device to the adjacent switching device and the same destination SDROT from the adjacent switching device, the amount of SDROT configuration information managed in the entire network can be reduced. Also, when a network failure occurs, the transit switching equipment that detects the failure autonomously performs SDRO.
It is possible to change T to realize a quick detour operation.
Further, when a new SDROT is set, it can be set only by interacting with the adjacent exchange device, which has the effect of simplifying the SDROT setting operation. In addition, by instructing the adjacent switching device to set a new SDROT via the local switching device from the adjacent switching device, some SD
By using ROT addition, all the switching devices in the network can add the additional SD.
A new SDROT setting using ROT can be performed.

[Brief description of drawings]

FIG. 1 is a network configuration diagram showing a packet relay method according to an embodiment of the present invention.

FIG. 2 is an SD of the switching device 1 according to the embodiment of the present invention.
It is a ROT composition table.

FIG. 3 is an R diagram of an intra-network relay packet according to an embodiment of the present invention.
It is a figure which shows an OT information area.

FIG. 4 is a diagram showing an RO of the exchange device 2 according to the embodiment of the present invention.
It is a T-SDROT correspondence table.

FIG. 5 is an SDR when a network failure occurs according to an embodiment of the present invention.
It is a figure which shows the example of OT switching.

FIG. 6 is a diagram showing a new SDROT setting procedure for the switching devices 3 to 4 according to the embodiment of the present invention.

FIG. 7 is a SDROT configuration table for the switching device 4 possessed by the switching device 3 according to the embodiment of the present invention.

FIG. 8 is a diagram showing an SDROT setting message packet format according to an embodiment of the present invention.

FIG. 9 is a ROT-SDROT correspondence table for the incoming relay line 23 that the switching device 2 according to the embodiment of the present invention has.

FIG. 10 is a diagram showing a SDROT setting instruction message packet format according to an embodiment of the present invention.

FIG. 11 is a diagram showing a method of packet relay by a conventional packet switching device.

FIG. 12 is a switching device 4 of a conventional packet switching device 1.
It is a destination SDROT configuration table.

FIG. 13 is an incoming relay line ROT / outgoing relay line ROT correspondence table possessed by the conventional packet switching devices 2 and 5.

FIG. 14 is an incoming relay line ROT / outgoing relay line ROT correspondence table possessed by the conventional packet switching devices 2 and 5.

[Explanation of symbols]

1 to 5 Packet switching device 6 to 11 and 23 Relay line 12 to 17 and 24 Logical relay route between adjacent switching devices (RO
T) 18 to 22, 25, 26 Logical relay route (SDROT) between originating and terminating switching devices

Claims (4)

[Claims] 1. A plurality of packet switching devices for transmitting and switching data in a packet format are installed, these are connected to each other by a relay line to form a network, and the relay lines connecting the respective switching devices are logically connected. A relay route (hereinafter abbreviated as ROT) between adjacent switching devices is defined, and the ROT and the packet switching devices forming the network are alternately connected to each other to connect the originating and destination switching devices from the originating packet switching device to the destination packet switching device. In a packet switching device having a packet relay method for defining a relay route (hereinafter abbreviated as SDROT) and transferring a packet addressed to the destination packet switching device by the SDROT, an SDROT between the packet switching devices is transmitted from the source packet switching device to the SDROT. ROT to a packet switching device adjacent to the originating packet switching device and the adjacent packet switching device Relaying the defined packet by the connection with SDROT to La adhesive changer, packet switching device, characterized in that. 2. An SDRO from the packet switching device or the fault detection packet switching device which detects a fault when a fault occurs and becomes unusable due to the fault.
SDRO addressed to the same destination packet switching device that can use another T
The packet switching device according to claim 1, wherein the packet switching device is replaced with T. 3. An RTO not used on a trunk line between the own packet switching device and another packet switching device adjacent to the packet switching device in the own packet switching device. SD reserved for a new SDROT setting addressed to the adjacent packet switching device and having the reserved ROT number and the destination packet switching device number for the new SDROT setting as contents
When a ROT setting message packet is transmitted and a response packet to the SDROT setting message packet is received from the adjacent packet switching device, the new SDR
Means for additionally setting an OT as an SDROT for the destination packet switching device, and an incoming trunk line number at which the message packet is received when the SDROT setting message packet is received from a packet switching device adjacent to the own packet switching device , And the ROT number and the destination packet switching device number, which are the contents of the message packet, are recognized, one SDROT from the own packet switching device addressed to the destination packet switching device is secured, and the ROT on the incoming trunk line is secured. A means for storing the SDROT from the own packet switching device in association with each other and returning a response packet to the adjacent packet switching device that has transmitted the SDROT setting message packet. The packet switching device described. 4. A means for transmitting a SDROT setting instruction message packet having an instruction to newly set an SDROT addressed to another switching device via the own packet switching device, to the adjacent packet switching device. When the packet switching device receives the SDROT setting instruction message packet from the adjacent packet switching device, the new packet switching device uses the unused ROT on the incoming trunk line that has received the message packet to perform the new SDROT setting. 4. The packet switching device according to claim 3, further comprising: