JP3812668B2 - Link-up method and link-up system for each port of switching hub - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a link-up method and a link-up system for each port of a switching hub.
[0002]
[Prior art]
As a redundant means of a line in Ethernet, there are a spanning tree protocol (IEEE802.1D) that duplicates a path between switching hubs, a VRRP (Virtual Router Redundancy Protocol) that duplicates an IP router, and the like.
[0003]
In these protocols, packets are periodically transmitted between switching hubs, and the normality of the communication path is confirmed by confirming that the packets arrive from the other party. When the packet does not reach the partner switching hub, the switching hub has a function of determining that a failure has occurred in the communication path and switching to a redundant line.
[0004]
In the current Ethernet, bus-type connection networks such as 10BASE-5 and 10BASE-2 are almost not used, and there is no connection between switching hubs or between switching hubs and terminals such as 10BASE-T, 100BASE-TX, 1000BASE-SX. One-to-one connection is common.
[0005]
The switching hub always detects the link sent from the connected switching hub, but if a line failure occurs, not only will the spanning tree and VRRP packets not reach, but the link will also go down. The majority.
[0006]
In the case of such a line failure, packets will not reach between switching hubs, switching of communication paths will occur due to the spanning tree or VRRP described above, and communication between terminals will be restored within a few seconds to several tens of seconds. It was.
[0007]
In addition, when the faulty line is restored, the packets reach between the switching hubs, so the original line is used by spanning tree or VRRP.
[0008]
There was no problem with this method when the line was completely disconnected due to a communication path failure.
[0009]
In addition, as a conventional technique, there is a link change detecting means for detecting a change in the link state of a predetermined port, and a registered address in the address table corresponding to the link state change quickly before the aging time elapses. There are a switching hub for managing port addresses and a registered address update processing method (see, for example, Patent Document 1).
[0010]
Further, as a conventional technique, when a cable disconnection is detected at a port of one transmission device in a network composed of a plurality of transmission devices having at least a port for a control terminal that controls the transmission device, the port is There is a transmission apparatus having an advanced security system that cancels the state of logging in to the own transmission apparatus or another transmission apparatus via the network (for example, see Patent Document 2).
[0011]
[Patent Document 1]
JP 2001-101630 A [Patent Document 2]
JP-A-11-259423 [0012]
[Problems to be solved by the invention]
However, the above-described prior art has the following problems.
[0013]
When a failure that causes the line quality to become unstable occurs, the link between the switching hubs may repeatedly go up and down, and communication may or may not be possible.
[0014]
When communication between switching hubs becomes impossible, switching of communication paths occurs due to spanning tree or VRRP, but when communication between switching hubs becomes possible, the original path is used.
[0015]
However, in the case of a failure that makes the line unstable like this, just because communication between switching hubs has become possible, the failure has not been recovered, and communication may soon be lost. is there. When communication becomes impossible again, a path change occurs each time. Since communication between terminals is not possible while the route is switched, there has been a problem that communication between terminals will not be restored indefinitely when such a line failure occurs.
[0016]
This is a phenomenon often seen when there is a problem with an optical fiber, especially in communication using an optical fiber such as 1000BASE-SX.
[0017]
In view of the above-mentioned problems of the prior art, the object of the present invention is to prevent a route from being used until there is an operator's intervention if the link of the port goes down even once due to a line failure. To provide a link-up method and a link-up system for each port of a switching hub, which can prevent frequent switching.
[0018]
[Means for Solving the Problems]
The link-up method for each port of the switching hub of the present invention is as follows:
Link-up mode is a link-up method for each port of the switching hub that can be set by a command as either automatic mode or manual mode. In the automatic mode, a cable is connected to the port of the switching hub and a link is established with the partner device. After the connection is established, the port will be linked up, and if the cable is disconnected, the link will be down.However, if the cable is connected again, the link will be up again. The port will not link up until the up permission command is entered.
[0019]
In addition, a table for setting the link-up mode for each port may be prepared, and the setting may be changed from the management terminal via the RS-232C port.
[0020]
In addition, it consists of a CPU that controls the operation of the switching hub by a program, an RS-232C port for command input, a switch unit, and a plurality of ports. The CPU determines whether the port can be used or not by the program. For each port of the switching hub, the RS-232C port controls the operation of the switching hub by inputting a command by connecting a management terminal for managing the switching hub. A link-up method in which the port link-up mode is confirmed by a program running on the CPU, and when the link-up mode is the manual mode, the CPU sets the port to be unusable, and the port is used. The link-up that allows the port to be used from the management terminal The stage that continues until the enable command is input, and when the link-up permission command that permits the use of the port is input from the management terminal, the CPU sets the port to be enabled and the link-up is detected. A step of waiting, a step of starting communication when link up is detected, a step of monitoring link down during communication, a step of ending communication and returning to the beginning when link down occurs during communication, and You may have.
[0021]
The link-up system for each port of the switching hub of the present invention is:
A link-up system for each port of the switching hub, which can be set as a link-up mode by either an automatic mode or a manual mode by a command, and the automatic mode is a link to a partner device when a cable is connected to the port of the switching hub. After the connection is established, the port will be linked up, and if the cable is disconnected, the link will be down.However, if the cable is connected again, the link will be up again. The port will not link up until the up permission command is entered.
[0022]
In addition, a table for setting the link-up mode for each port may be prepared, and the setting may be changed from the management terminal via the RS-232C port.
[0023]
In addition, it consists of a CPU that controls the operation of the switching hub by a program, an RS-232C port for command input, a switch unit, and a plurality of ports. The CPU determines whether the port can be used or not by the program. For each port of the switching hub, the RS-232C port controls the operation of the switching hub by inputting a command by connecting a management terminal for managing the switching hub. A link-up system in which the port link-up mode is checked by a program running on the CPU, and when the link-up mode is the manual mode, the CPU sets the port to be unusable and the port is used. The state where it is not possible is a link address that permits the use of the port from the management terminal. The CPU continues to set the port, and if the link-up permission command for permitting the use of the port is input from the management terminal, the CPU sets the port to be usable, and the link-up is detected. Waiting for a link, when a link up is detected, starting a communication, monitoring a link down during communication, and terminating a communication and returning to the beginning if a link down occurs during the communication. You may have.
[0024]
The present invention is characterized in that when a link down unintended by an operator occurs at a port in use of the switching hub, a function is provided to prevent the link up again without intervention by the operator. That is, if a port is linked down even once, the port can be made unavailable without operator intervention, and a line with poor quality can be avoided.
[0025]
In the switching hub according to the present invention, either the automatic mode or the manual mode can be set by a command as a link-up method for each port of the switching hub.
[0026]
In the automatic mode, when a cable is connected to the port of the switching hub and a link is established with the partner device, the port is linked up. If the cable is disconnected, the link goes down, but if the cable is connected again, the link goes up again. This is the same operation as a conventional switching hub.
[0027]
On the other hand, in manual mode, even if a cable is connected to a port of the switching hub, the port is not linked up until the operator inputs a link up permission command.
[0028]
According to the present invention, when a link of a port is down even once due to a line failure, it is possible to prevent frequent switching of a route by not using the port until there is operator intervention.
[0029]
However, if this function is added to all the ports of the switching hub, devices such as terminals that can be turned off cannot be connected, so this function can be set for each port, and the redundant line This function can be enabled only for ports with.
[0030]
The present invention makes it possible to prevent a terminal connected to a port of a switching hub from being connected to another terminal by a third party.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a switching hub 100 having a link detection method according to an embodiment of the present invention includes a CPU 110 that controls the operation of the switching hub by a program, an RS-232C port 120 for command input, and a switch unit. 130 and interface ports 141 to 14n.
[0032]
In addition to controlling the operation of the switching hub by the program, the CPU 110 can control whether the ports 141 to 14n can be used or not for each port.
[0033]
The RS-232C port 120 can control the operation of the switching hub 100 by inputting a command by connecting a management terminal 200 for managing the switching hub.
[0034]
Next, the overall operation of the embodiment of the present invention will be described in detail with reference to FIG. 1, FIG. 2, and FIG.
[0035]
First, a table for setting the link-up mode for each port is prepared. As shown in FIG. 2, a table of 1 bit per port may be prepared. If the value of this table is 0, it is determined to be automatic, and if it is 1, manual. These values are initially set to 0, that is, automatic, and this setting can be changed from the management terminal 200 via the RS-232C port 120.
[0036]
Next, the case where the port 2 is set to the manual mode will be described with reference to the flowchart of FIG.
[0037]
The mode of the port 142 is confirmed by a program operating on the CPU 110 (S1). If the mode is the manual mode, the CPU 110 disables the port 142 (S2).
[0038]
In general, an Ethernet port has a common register called MII, and can be disabled by writing a value in a specific bit of the register.
[0039]
The state in which the port 142 cannot be used continues until a link-up permission command permitting the use of the port 142 is input from the management terminal 200 (S3).
[0040]
When a link-up permission command permitting use of the port 142 is input from the management terminal 200 (S4), the CPU 110 sets the port 142 to be usable (S5).
[0041]
Thereafter, it waits for detection of link up (S6), and when link up is detected (S7), communication is started (S8). Link down is monitored during communication (S9). If link down occurs during communication (S10), communication is terminated (S11) and the process returns to the beginning.
[0042]
As described above, when the port is set to the manual mode, it is possible not to link up again without operator intervention.
[0043]
【The invention's effect】
As described above, the present invention has the following effects.
[0044]
The first effect is that after the switching hub port goes down due to a line failure and switches to a redundant line (detour), the line is not used even if the failed line is temporarily recovered. It is possible to prevent frequent switching.
[0045]
The reason is that a port that has been linked down is not linked up without operator intervention. After a failure occurs on a line, even if the failure is recovered, the failed line is not used until the operator removes the cause of the failure and enters a command to use the original line.
[0046]
The second effect is that even if a line failure occurs for a very short time due to an instantaneous disconnection of the line, the line is not used, so it is possible to avoid using a line that may cause a failure again. That is the point.
[0047]
This is because a port that has been linked down once is not linked up without operator intervention regardless of the time of link down.
[0048]
A third effect is that a port connected to the switching hub can be prevented from being used without permission by a third party.
[0049]
Even with the conventional switching hub, it was possible to disable the port, but the cable of the port in use was disconnected, a new terminal was connected by a third party, and the port was used without permission. I couldn't prevent it. According to the present invention, even if another terminal is connected to the port in use, the port can be made unusable.
[0050]
The fourth effect is that a new hub is connected by a third party between the switching hubs to prevent a packet flowing on the line from being intercepted.
[0051]
In order to connect a new hub between the switching hubs, it is necessary to once disconnect the cable connecting the switching hubs. However, the port once disconnected is made unusable without operator intervention.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a switching hub provided with a link detection method according to an embodiment of the present invention.
FIG. 2 is a diagram showing a table for setting a link-up mode for each port.
FIG. 3 is a diagram illustrating a flowchart when a port is set to a manual mode.
[Explanation of symbols]
100 switching hub 110 CPU
120 RS-232C port 130 Switch part 141-14n Interface port 200 Management terminal

Claims (6)

A link-up method for each port of the switching hub, wherein either the automatic mode or the manual mode can be set by a command as the link-up mode,
In the automatic mode, when a cable is connected to the port of the switching hub and a link is established with the partner device, the port is linked up. When the cable is disconnected, the link is down, but when the cable is connected again, the link is up again. And
The manual mode is a link-up method for each port of the switching hub, in which, even if a cable is connected to the port of the switching hub, the port is not linked up until a link-up permission command is input. The table for setting the link-up mode for each port is prepared, and the setting can be changed from the management terminal via the RS-232C port. Link up method. Consists of a CPU that controls the operation of the switching hub by a program, an RS-232C port for command input, a switch unit, and a plurality of ports.
The CPU controls whether the port can be used or not for each port by a program,
3. The RS-232C port is connected to a management terminal for managing the switching hub, thereby inputting a command to control the operation of the switching hub. The link-up method described in
Checking the port link-up mode by a program running on the CPU;
When the link-up mode is the manual mode, the CPU sets the port to be unusable;
The state in which the port is unusable continues until a link-up permission command for permitting use of the port is input from a management terminal;
When a link-up permission command for permitting use of the port is input from the management terminal, the CPU sets the port to be usable;
Waiting for link up to be detected,
If the link up is detected, starting communication;
Monitoring the link down during communication,
A link-up method for each port of the switching hub, including a step of terminating communication and returning to the beginning when the link-down occurs during communication. A link-up system for each port of the switching hub, wherein either the automatic mode or the manual mode can be set by a command as the link-up mode,
In the automatic mode, when a cable is connected to the port of the switching hub and a link is established with the partner device, the port is linked up. When the cable is disconnected, the link is down, but when the cable is connected again, the link is up again. And
The manual mode is a link-up system for each port of the switching hub in which the port does not link up until a link-up permission command is input even if a cable is connected to the port of the switching hub. 5. A table for setting a link-up mode for each port is prepared, and the setting can be changed from the management terminal via the RS-232C port. Link-up system. Consists of a CPU that controls the operation of the switching hub by a program, an RS-232C port for command input, a switch unit, and a plurality of ports.
The CPU controls whether the port can be used or not for each port by a program,
6. The RS-232C port is connected to a management terminal for managing the switching hub, so that a command can be input to control the operation of the switching hub. The link-up system described in
Checking the port link-up mode by a program running on the CPU;
When the link-up mode is the manual mode, the CPU sets the port to be unusable;
The state in which the port is unusable continues until a link-up permission command for permitting use of the port is input from a management terminal;
When a link-up permission command for permitting use of the port is input from the management terminal, the CPU sets the port to be usable;
Waiting for link up to be detected,
If the link up is detected, starting communication;
Monitoring the link down during communication,
A link-up system for each port of the switching hub, which includes a step of terminating communication and returning to the beginning when the link down occurs during communication.

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