JPH0251928A - System for avoiding isolated packet exchange - Google Patents

Abstract

PURPOSE:To prevent the control of a packet exchange from being disabled by releasing the block of a line already blocked and setting newly a logic information line if no path to set the logic information line exists. CONSTITUTION:Suppose that a relay line L12 is blocked and a logic information path setting section U1 of a packet exchange P1 sets a logic information path R2, then if a line block instruction is sent from a network management equipment N to a packet exchange P1 to block a relay line L13, the packet exchange P1 blocks the relay line L13. Then the logic information path setting section U1 is going to select other relay line, since no available relay line exists, the block of the relay line L12 blocked already is released automatically to set the logic information path R1. Thus, even if the network management equipment blocks all the relay lines in error, the disabled control of the relevant packet exchange is prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for avoiding isolation of packet switching equipment, and in particular, the present invention relates to a method for avoiding isolation of packet switching equipment, and in particular, the present invention relates to a method for avoiding isolation of packet switching equipment, and in particular, in order to set up a logical information path, a packet switching equipment releases a relay line that has already been blocked. This invention relates to a switching device isolation avoidance method.

[Conventional technology]

Conventionally, when a relay line between packet switching devices in a packet switching network is blocked, whether or not that packet switching device becomes isolated by cutting off the logical information path connection with other packet switching devices, that is, from the network management device The packet switching device does not check whether or not the control information can be transmitted, but is left to the judgment of the operator of the network management device.

[Problem that the invention seeks to solve]

In the conventional packet switching network described above, when a packet switching device receives a line blocking command from a network management device, even if the logical information path between the packet switching device and the network management device is not guaranteed, Since the corresponding line is unconditionally blocked, the logical information path between the packet switching device and the network management device may be disconnected. Since the network management device collectively controls the packet switching device using the logical information path, there is a problem that if the logical information path is not established, the packet switching device cannot be controlled forever.

An object of the present invention is to have a packet switching device controlled by a network management device determine whether or not there is a logical information path that it uses, and when it determines that there is no logical information path, the packet switching device automatically switches to a relay line. An object of the present invention is to provide a method for avoiding isolation of a packet switching device, which can secure a logical information path with a network management device by controlling the blocking function of the packet switching device.

[Means for solving problems]

The isolated packet switching system of the present invention avoids isolation of packet switching devices in a packet switching network that includes a plurality of packet switching devices and a network management device that has a function of sending out control information for controlling each packet switching device. In this method, a logical information path setting unit provided in each packet switching device sets a logical information path provided between itself and the network management device, and the logical information path setting unit provided in each packet switching device sets the logical information path provided between the packet switching device and the control information transmitted via this logical information path. In response to the line blocking command, the packet switching device that includes itself is controlled to block the specified relay line between it and other packet switching devices, and as a result of blocking this relay line, the previously set logical information path is When the network is disconnected, it is detected, a new logical information path is set up using an unblocked trunk line, and the setting of the logical information path is confirmed using any of the available trunk lines. If the configuration confirmation information cannot be received from the management device, it is determined that there is no relay line between the network management device and the network where a logical information path can be set, and a new logical information path can be secured for the already blocked relay line. It is configured to be released sequentially until the end.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention.

Packet switching device P1 and packet switching device P3 are connected by a relay line L13, packet switching device P1 and packet switching device P2 are connected by a relay line L12, packet switching device P2 and Bakut switching device πP3 are connected by a relay line L23, The packet switching device P2 is connected to the network management device N via a relay line L2N. Packet switching device P1゜P2. P3 is a logical information path setting unit U1 for setting a logical information path with the network management device N, respectively.
, U2. It has U3. Here, it is assumed that the logical information path setting unit U1 is currently setting the logical information path R1 along the path P1→L12→P2→L2N-N. In this state, the network management device N uses the logical information path R1 to send a line blocking command to the packet switching device P1 to block the relay line L12. When receiving the line blocking command, the packet switching device P1 blocks the relay line L12. When the logical information path setting unit U1 determines that the logical information path R1 is immediately disconnected due to the blockage of the relay line L12, it selects another relay line L13 and performs the steps P1→L13→P3→
A new logical information path R2 is established along the route L23→P2→L2N-+H. The network management device N sends back configuration confirmation information on the logical information path R2, thereby confirming the configuration. In this state, when the network management device N again sends a line blocking command to the packet switching device P1 to block the relay line L13 via the logical information path R2, the packet switching device P1 first blocks the relay line L13. LL
The trunk line L13 is blocked in the same way as when the relay line L13 was blocked. When the logical information path setting unit U1 determines that the logical information path R2 is disconnected by receiving the packet-level disconnection request packet issued from the packet switching device P1,
An attempt is made to select another trunk line again, but since there is no trunk line that can be used, the trunk line L12, which is already blocked, is automatically unblocked and the switch is switched from P1 to L1 again.
2→P2→L2N-4-N logical information path R1 is set.

〔Effect of the invention〕

As explained above, the present invention is capable of establishing a logical information path with a network management device even if all relay lines of a packet switching device are temporarily blocked by a line blocking command from the network management device. If it is determined that there is no route, the already blocked line is unblocked and a new logical tit route is set.
Even if the network management device accidentally blocks all the relay lines, it is possible to prevent the corresponding packet switching device from becoming uncontrollable.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one embodiment of the present invention. L12. L2B, L13. L2N...relay line, N.
...Network management device, PI, R2, R3... Packet switching device, R1, R2... Logical information path, Ul. U2. U3...Logic information path setting unit. Agent Patent Attorney Susumu Uchihara

Claims (1)

[Claims] In a packet switching device isolation avoidance method for a packet switching network consisting of a plurality of packet switching devices and a network management device that has a function of sending out control information for controlling each packet switching device, The logical information path setting section sets up a logical information path between itself and the network management device, and receives a line blocking command included in the control information sent via this logical information path. Controls a packet switching device to block a specified relay line between it and another packet switching device, and detects when the previously set logical information path is disconnected as a result of blocking this relay line, and blocks it. A new logical information path is set using a relay line that has not been used, and the configuration confirmation information for the logical information path cannot be received from the network management device, even if any of the available relay lines is used. In this case, it is determined that there is no trunk line that can set up a logical information path with the network management device, and the relay circuits that have already been blocked are sequentially released until a new logical information path can be secured. A method for avoiding isolation of packet switching equipment.