JP2003158529A - Lan system and power supply control system for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply control system for a common device connected to a LAN system with a plurality of LAN ports and receiving power supplied from the LAN system that can control supply of power to the common device without the need for manual intervention on the basis of a result of detecting a change in a link state between the LAN system and clients connected thereto. SOLUTION: The power supply control system is configured such that the system detects a link state between the LAN system and the clients connected to LAN ports, supplies power to the common device connected to power ports when a link is formed between the LAN system and at least one of the clients, and stops the supply of power to the common device connected to the power port when no link is formed between the LAN system and all the clients.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a plurality of LANs (Lo
cal area network) related to a power control method of a common device connected to a LAN device having a port and supplied with power from the LAN device, and particularly detecting a change in a link state between the LAN device and a client connected thereto. The present invention relates to a power control method for a common device that can control power supply to the common device without human intervention according to the result.

A LAN for connecting a server having a plurality of processing functions, a database server for storing a huge amount of data, and a large number of clients used by a person who wants to use the function of the server is widely used. By the way, although the power consumption of the devices constituting the LAN has been greatly reduced over a long period of time, the number of LANs themselves is huge and the number of devices that can be connected to one LAN is also increasing. LA in society as a whole
The electric energy consumed by N is enormous.

Therefore, in operating each LAN, it is necessary to surely suppress unnecessary electric energy consumption.

[0004]

2. Description of the Related Art In a LAN, a common device such as a printer or an image display device is connected to a server or a client, for example, via a hub, and is used in a corporation, a public office, or various research institutions. There is a form. LA of this form
In N, on / off management of the power supply of the device often depends on the goodwill of the user of each client.

Among various devices, the client is provided so that each user can use it exclusively, and in order to maintain the security of information, the user himself enters the ID number after turning on the power. It is customary for the user to turn off the power when starting up and ending the use, so the on / off status of the user's enrollment / absence and the client's power are the same, and unnecessary electricity is consumed. Energy consumption is suppressed.

[0006]

However, a common device such as a printer is not always arranged in the vicinity of the user, and a specific user uses the LAN by another user. In most cases, it is impossible to know whether they are doing it or not. Therefore, it is difficult to strictly control the power supply of the common device, and power is continuously supplied to the common device even when there are no users, and unnecessary electric energy is continuously consumed. This is a serious problem that leads to global warming and environmental destruction.

In view of such a problem, the present invention provides a plurality of L's.
The present invention relates to a power control method of a common device connected to a LAN device having an AN port and supplied with power from the LAN device, and in particular, depending on a result of detecting a change in a link state with a client connected to the LAN device. It is an object of the present invention to provide a power control method for a Lan device that can control power supply to the common device without human intervention.

[0008]

The first invention is to provide a plurality of L's.
A power control method for a LAN device comprising an AN port and a plurality of power supply ports for supplying power to a common device constituting a LAN, wherein a link between a client connected to the LAN device via the LAN port The status is detected, and when a link is formed with at least one client, power is supplied to the common device connected to the power port, and when no links are formed with all the clients. A LAN characterized by stopping power supply to a common device connected to the power port
This is a power control system for the device.

According to the first invention, the LAN device and the LA
A link state with a client connected to the N port is detected, and when a link is formed with at least one client, power is supplied to a common device connected to the power port, Since the power supply to the common device connected to the power supply port is stopped when the link with the client is not formed, the common device connected to the power supply port may consume unnecessary electric energy. If there is no client and at least one client has a link, it is possible to reliably supply power to the common device connected to the power port.

A second aspect of the invention is to provide a plurality of LAN ports and L
A power control method for a LAN device having a plurality of power ports for supplying power to a common device constituting an AN, comprising:
The link state between the client connected to the LAN device via the AN port is detected, and when a link is formed with at least one client, the power is supplied to the common device connected to the power supply port. And sends information indicating that a link is formed in the LAN device to the upper LAN device, and when no link is formed with all the clients, it is connected to the power supply port. This is a power control method for a LAN device, characterized in that the power supply to the existing common device is stopped and information indicating that a link is not formed in the LAN device is transmitted to the upper LAN device.

According to the second invention, the LAN device and the LA
A link state with a client connected to the N port is detected, and when a link is formed with at least one client, power is supplied to a common device connected to the power port, Information to the effect that a link is formed in the LAN device to the LAN device, and when no link is formed with all the clients, the power supply to the common device connected to the power supply port is sent. Supply is stopped and higher L
Since the information indicating that the link is not formed in the LAN device is transmitted to the AN device, it is possible to accurately control the power supply of the common device connected to the LAN device and also to the upper LAN device. Power supply control of the connected common device can also be accurately performed.

A third aspect of the present invention is to provide a plurality of LAN ports and L
A power supply control system for a LAN device having a plurality of power supply ports for supplying power to a common device constituting an AN, comprising: a power supply control system for a LAN device according to the first invention; and a LAN device for the second invention. This is a power supply control method for a LAN device, which is characterized by switching between a power supply control method. According to the third invention, it is possible to switch between the power control method for the LAN device of the first invention and the power control method for the LAN device of the second invention. It is possible to select one of the function to be performed and the function to be obtained by the second invention, and it is possible to apply the function commonly to the independent LAN device and the dependent LAN device.

According to a fourth aspect of the present invention, in any one of the power supply control method in the LAN device of the first invention to the power supply control method in the LAN device of the third invention, before starting the power supply to the common device, and A power control method for a LAN device, wherein a protection time is provided before stopping the power supply to the common device. According to the fourth invention, before the power supply to the common device is started, and before the power supply to the common device is stopped, the protection time is provided, so after the start of the power supply is determined, or After deciding to stop the power supply,
Even if the link status changes, hunting between power on and power off does not occur, and power control can be stabilized.

A fifth aspect of the invention is a power supply control system in the LAN device of the first aspect of the invention, or an LA of the second aspect of the invention.
It is a LAN device characterized by applying either the power control system in the N device or the power control system in the LAN device of the third invention. According to a fifth invention, the LAN device is a power supply control system in the LAN device of the first invention, a power supply control system in the LAN device of the second invention, or the LAN device of the third invention. Any one of the power control methods in the above, the power control of the common device connected to the LAN device, or
It becomes possible to accurately control the power supply of the common device connected to the upper LAN device.

[0015]

DETAILED DESCRIPTION OF THE INVENTION The technique of the present invention will be described in detail below with reference to the drawings. In addition, for concrete explanation, LAN
An example in which a hub is applied as the device will be described.
FIG. 1 is a configuration example (No. 1) of a LAN system, which is an example of a mode in which a common device and a client are connected to a single hub.

In FIG. 1, 1 is a hub # 1, 11 power control units, 12 power ports P # 1 and 12a power ports P # 2, 13 LAN ports L # 1 to 13d L.
It has an AN port L # 5. The power port P # 1
And the power port P # 2 is a mere power outlet,
The LAN ports L # 1 to L # 5 are not merely connectors, but have a communication function with the connected common device and client.

Reference numeral 2 denotes a server # 1, which is supplied with power from the power port P # 1 and is connected to the LAN port L # 1. 3 is a printer # 1, which is supplied with power from a power port P # 2 and is connected to a LAN port L # 2. The server 2 and the printer # 1 are common devices in the LAN system, and the power supply control system for them is the main technology of the present invention.

4 is a client # 1 connected to the LAN port L # 3, 4a is a client # 2 connected to the LAN port L # 4, and 4b is a LAN port L # 5.
Client # 3 connected to. Then, the power supplies of the clients # 1 to # 3 are individually supplied at the locations where they are arranged, and the power supply control is left to the user who uses the LAN system via each client.

FIG. 2 shows an example of a LAN system configuration (No. 2) in which a common device and a client are connected to two cascade-connected hubs. In FIG. 2, 1 is hub # 1, 1a is hub # 2, and each hub is 1
1 power control unit, 12 power ports P # 1 and 12a power ports P # 2, 13 LAN ports L # 1 to 13
LAN port L # 5 of d.

Incidentally, the power supply port P # 1 in each hub
And the power port P # 2 is a mere power outlet,
The LAN ports L # 1 to L # 5 are not merely connectors, but have a communication function with the connected common device and client, as in the configuration of FIG. 2 is the server # 1, which is the power port P # of the hub # 1.
1 is powered by LAN port L # 1 of hub # 1
Connected with. 3 is a printer # 1, which is supplied with power from a power port P # 2 of the hub # 1 and is a LAN of the hub # 1.
It is connected to port L # 2.

Reference numeral 4 denotes clients # 1 and 4a connected to the LAN port L # 3 of the hub # 1 and LANs of the hub # 1.
It is the client # 2 connected to the port L # 4. 3a is a printer # 2, which is a power port P # of the hub # 2.
1 is powered by LAN port L # 1 of hub # 2
Connected with. 4c is LAN port L # of hub # 2
Client # 4, 4d connected to 2 is hub # 2
Client # connected to LAN port L # 3
Reference numerals 5 and 4e denote the client # 6 connected to the LAN port L # 4 of the hub # 2.

Here, the feature of the configuration of FIG. 2 is that the LAN port L # 5 of the hub # 2 is connected to the LAN port L # 5 of the hub # 1, and the hub # 1 and the hub # 2 are connected in cascade. That is the point. The server # 1 and printer # 1 connected to the hub # 1 and the printer # 2 connected to the hub # 2 are common devices in the LAN system configured as shown in FIG. In this case, the client connected to the hub # 2 communicates with the server # 1 connected to the hub # 1 to perform the required processing. Printer #
1 is used by clients connected to hub # 2,
Although it is possible to use the printer # 2 by a client connected to the hub # 1, in this example, the printer # 2 is used.
1 is used only by the client connected to the hub # 1, and the printer # 2 is assumed to be used only by the client connected to the hub # 2.
The power supply control system for these common devices is the main technology of the present invention.

The power supplies of the clients # 1 and # 2 connected to the hub # 1 and the clients # 4 to # 6 connected to the hub # 2 are individually supplied at the locations where they are arranged. As in the LAN system having the configuration of FIG. 1, the power control is left to the user who uses the LAN system through each client.

Here, the hub # 1 in the configuration of FIG. 1 is a single hub, and the hub # 1 in the configuration of FIG. 2 is a superordinate hub with respect to other hubs, so these are called independent hubs. On the other hand, since the hub # 2 having the configuration shown in FIG. 2 is connected to the hub # 1 in cascade, it will be referred to as a subordinate hub to distinguish the hub types. It should be noted that the above configurations of FIGS. 1 and 2 are merely examples, and the number of power supply ports and LAN ports is arbitrary within the range of physical restrictions, and the type and number of common devices to be connected and the number of connected common devices are connected. The number of clients is also arbitrary within the range of physical constraints.

For example, in the configuration of FIG. 2, a server can be connected to hub # 2. In the above, it is assumed that each hub has its own printer.
It is also possible to commonly use the printer # 1 of the hub # 1 for all the clients without connecting the printer to the printer 2.
In addition, the number of hub stages is not limited to two when a plurality of hubs are connected in cascade as in the configuration of FIG. 2, and may be any number within the standard of the hub.

Following the configuration example of the LAN system described above,
The configuration of the hub will be described. FIG. 3 shows the configuration of the hub with a focus on the power supply controller. In FIG. 3, 1 is a hub, 11 power control units, 12 power ports P # 1 and 1
2a power source ports P # 2, 13 LAN ports L # 1 to 13d LAN port L # 5.

The power control unit 11 is a central processing unit (abbreviated as "CPU" in the figure. This is Cent.
A general abbreviation for the acronym for ral Processing Unit. ) 11-1, bus 11 of central processing unit 11-1
-2, a contact control circuit 11-3 for controlling on / off of power to each power port, a timer 11-4 for setting a protection time until contact control, and connection to each power port and LAN port The type of device being
A connection management table 11-5 that stores the link status of each LAN port, a switch 11-6 that turns on / off the power to each power port, and a commercial AC input outlet PIN 11-7 are provided.

Here, the link state means a state in which communication with a connected device is possible or a state in which communication with a connected device is impossible. And when distinguishing these,
The former is referred to as an up state (hereinafter simply referred to as “up”) and the latter is referred to as a down state (hereinafter simply referred to as “down”). FIG. 4 is a configuration example of the connection management table.

In the connection management table, the type of the connected device and the link state are stored with the LAN port number and the power port number as addresses. First, regarding the connection device type, for example, a common device other than a server is represented by A, a client is represented by B, a server is represented by C, and an adjacent hub is represented by D.
Further, the connected device type for the power supply port is expressed by the number of the LAN port to which the device connected to the power supply port is connected.

This is information that is entered and stored by a person in charge of the operation of the LAN system, such as a maintenance person. Next, the link status is expressed as Up (meaning “up”) when the link status is the connection status, and Dn (meaning “down”) when the link status is the non-connection status.
Note that it is not necessary to monitor the link status for the common device connected to the LAN port, and the link status itself is meaningless for the power supply port, so on the connection management table, Dc stands for Don't Care. Express it.

Specifically, the L to which the client is connected
The link status of the AN port is obtained by the communication function provided in the LAN port detecting that the link status is up or down and notifying the central processing unit.
The central processing unit automatically writes and updates the connection management table. On the other hand, the link status related to the common device is ignored by the central processing unit even when notified from the LAN port, and the link status change is not written to the address in the connection management table. Further, since the link status is not notified from the power supply port, the central processing unit has nothing to do with the power supply port. “Dc” has the above two meanings.

The above expression is an abbreviation having a physical meaning so that a person reading this specification can easily understand it. However, the information actually stored in the connection management table is naturally expressed in binary. To be done. 5 and 6 are examples of stored information of the hub connection management table (part 1) in the system configuration of FIG. 1 and example of stored information of the hub connection management table in the system configuration of FIG. 1 (part 2). The storage information is described for two specific states in the configuration.

That is, FIG. 5 shows a case where the link status with all the clients in the configuration of FIG. 1 is down, and FIG. 6 shows the link status with a single client in the configuration of FIG. Shows the case where is up. This will be specifically described below. In the configuration of FIG. 1, the server # is connected to the LAN port L # 1 of the hub # 1.
1, the printer # 1 is connected to the LAN port L # 2, the client # 1 is connected to the LAN port L # 3, and the LAN port L # 4 is connected to the client # 1.
Client # 2 is connected to LAN port L # 5, and client # 3 is connected to LAN port L # 5.
Printer # 1 receives power supply from # 1
Power is supplied from # 2.

As described above, the common device other than the server is only the printer # 1, A is the client, B is the server, and C is the server. The server # 1 receiving power from the power port P # 1 is the LAN port L. Printer # 1 connected to # 1 and receiving power from power port P # 2 is LA
Since it is connected to the N port L # 2, the connection device types in the connection management table are as shown in FIG. 5 and FIG.

Regarding the link status, LAN port L #
It is a common device that is connected to 1 and L # 2, and the link status of the power ports P # 1 and P # 2 is meaningless,
When the link status with all the clients is down, the link status is as shown in FIG. LAN in this state
When the link state with the client # 1 connected to the port L # 3 is up, the link state becomes as shown in FIG.

As will be described later, when the link state changes from the state of FIG. 5 to the state of FIG. 6, power is supplied to the printer # 1, and the link state changes from the state of FIG. 6 to the state of FIG. When transitioning to, the power supply to the printer # 1 is stopped. Although not shown in FIGS. 5 and 6,
When the link status is already up on any other LAN port, the link status is already up on another LAN port, and when the link status is newly down on any LAN port, another LAN When the link status of the port is up, the power supply to the printer # 1 is continued.

FIG. 7 is a flowchart showing the operation of the power supply controller of the independent hub. After that, along the reference numerals in FIG.
The operation of the power supply control unit in the independent hub, that is, the hub # 1 having the configuration of FIG. 1 and the hub # 1 having the configuration of FIG. 2 will be described. S1. The central processing unit monitors whether there is a change in the link status of the LAN port and determines whether there has been a change.

This can be done by monitoring the link status up or down notification from the LAN port.
When there is no change (No), the above monitoring and determination are continued. S2. In step S1, if the link status has changed (Yes), the type of the LAN port that has changed is confirmed.

This is because the central processing unit can refer to the connection management table and confirm the LAN port type by adding the address of the LAN port when the link status is notified of up or down. Become. S3. It is determined whether or not the LAN port whose link status has changed is a monitoring target. This can be done by referring to the connection management table by using the notified address as a key by the central processing unit.

When the LAN port whose link status has changed is not the monitoring target (No), the processing is once terminated. S4. LA whose link status has changed in step S3
When the N port is the monitoring target (Yes), it is determined whether the change in the link status is up.

This can of course be done by notifying the LAN port of whether the link status is up or down. S5. If the change in the link status is up (Yes) in step S4, the connection management table is updated to reflect the change in the link status in the connection management table.

S6. The link status in the connection management table is searched to determine whether there is another LAN port whose link status is up. If there is another LAN port whose link status is up (Yes), power is already supplied to the common device and the power supply should not be stopped, so the processing is temporarily terminated.

S7. In step S6, when there is no other LAN port whose link status is up (No), a timer is started and the change of the link status is monitored for a predetermined time. This is an effective means for preventing the hunting in the power supply state even if the client that goes up after the power supply is determined once goes down.

S8. It is determined whether or not the link status has changed during the predetermined time. This is possible with the same monitoring as already explained. If there is a change in the link status (Yes), it is necessary to confirm the type of the changed port and determine whether there is a change in the monitoring target and whether the change is up or down. The process jumps to step S2 to continue the subsequent processing.

S10. If it is determined in step S8 that the link state has not changed (No), it is necessary to supply power to the printer together with the fact that there is no other LAN port up in step S6. Therefore, the contact control circuit is controlled. Then, the power supply to the printer is started and the processing is ended. This is an operation when the link state of FIG. 5 is changed to the link state of FIG.

S13. On the other hand, in step S4, when the change in the link state is down (No), the connection management table is updated to reflect the change in the link state in the connection management table. S14. In this state, it is determined by referring to the connection management table whether the link states of all LAN ports are down.

If there is a LAN port that is not down in this state (No), there is another client whose link state is up and the power supply must not be stopped.
The process ends without doing anything. S15. In step S14, when the link statuses of all the LAN ports are down (Yes), a timer is started and the change of the link status is monitored for a predetermined time.

This is an effective means for preventing the hunting in the power supply state even if the client which has gone down after having once decided to stop the power supply goes up. S16. It is determined whether or not the link status has changed during the predetermined time. This is possible with the same monitoring as already explained.

When the link status changes (Yes)
, It is necessary to check the type of the port that had B; W and determine whether there is a change in the monitoring target and whether the change is up or down, so jump to step S2 and the subsequent processing. To continue. S18. If there is no change in the link status in step S16 (No), it is necessary to stop the power supply to the printer together with the link status of all LAN ports being down in step S14. The contact control circuit is controlled to stop the power supply to the printer, and the process ends. This is the operation when the link state of FIG. 6 transits to the link state of FIG.

By controlling the power supply as described above, the power supply to the printer is stopped when the link status of all the clients is down, and the printer is surely connected to the printer when the link status of one client is up. Since power can be supplied, useless electric energy is not consumed, and power can be supplied accurately when necessary.

FIGS. 8 and 9 show an example of stored information in the connection management table of each hub in the system configuration of FIG. 2 (No. 1) and an example of stored information in the connection management table of each hub in the system configuration of FIG. 2 (No. 2). 2) describes stored information about two specific states in the configuration of FIG. That is, in FIG. 8, in the configuration of FIG.
1 shows that the link status with all the clients of 1 is down and the link status with all the clients of hub # 2 is down. In FIG. 9, all the hubs of hub # 1 in the configuration of FIG. 2 are shown. The link state with the client is down, and only the client # 4 of the hub # 2 is up. This will be specifically described below.

In the configuration of FIG. 2, the LAN of hub # 1
The server # 1 is connected to the port L # 1, the printer # 1 is connected to the LAN port L # 2, and the client # 1 is connected to the LAN port L # 3.
However, the client # 2 is connected to the LAN port L # 4, the server # 1 receives power from the power port P # 1, and the printer # 1 receives power from the power port P # 2.

The printer # 2 is connected to the LAN port L # 1 of the hub # 2, and the client # is connected to the LAN port L # 2.
4 and the client # 5 is connected to the LAN port L # 3 by L
The client # 6 is connected to the AN port L # 4, and the printer # 2 is supplied with power from the power port P # 1. Further, the LAN port L # 5 of the hub # 2 is connected to the LAN port L # 5 of the hub # 1.
1 is an independent hub, and hub # 2 is a subordinate hub.

Therefore, similarly to the description in FIGS. 5 and 6, the information stored in the connection management table is determined, and in the configuration of FIG. 2, the link status with all clients of hub # 1 is down and all of hub # 2 is down. Hub # 1 which is an independent hub when the link status with another client is down
8A is as shown in FIG. 8A, and the connection management table of hub # 2, which is a subordinate hub, is as shown in FIG. 8B, and in the configuration of FIG. When the link state is down and only the client # 4 of the hub # 2 is up, the connection management table of the hub # 1 which is an independent hub becomes as shown in FIG.
The connection management table of the hub # 2, which is the subordinate hub, is shown in FIG.
It becomes like (b).

As will be described later, when the link status changes from the status of FIG. 8 to the status of FIG. 9, power is supplied to the printer # 1 and printer # 2, and the link status is changed from the status of FIG. When transitioning to the state of FIG. 8, printer # 1
And the power supply to the printer # 2 is stopped. Also, FIG.
And, although not shown in FIG. 9, when the link state is newly brought up by any of the LAN ports, another L
If the link status of the AN port is up, and if the link status of one of the LAN ports is newly down and the link status of another LAN port is up, then printer # 1 and printer # 2 The power supply to is continued.

FIG. 10 is a flowchart showing the operation of the power supply control unit of the subordinate hub. Hereinafter, the operation of the power supply control unit in the subordinate hub, that is, the hub # 2 having the configuration of FIG. 2 will be described along the reference numerals of FIG. S1. The central processing unit monitors whether there is a change in the link status of the LAN port and determines whether there has been a change.

This can be done by monitoring the link status up or down notification from the LAN port.
When there is no change (No), the above monitoring and determination are continued. S2. In step S1, if the link status has changed (Yes), the type of the LAN port that has changed is confirmed.

This is because the central processing unit can refer to the connection management table and confirm the LAN port type by adding the address of the LAN port when the link status is notified of up or down. Become. S3. It is determined whether or not the LAN port whose link status has changed is a monitoring target. This can be done by referring to the connection management table by using the notified address as a key by the central processing unit.

If the LAN port whose link status has changed is not the monitoring target (No), the process is temporarily terminated. S4. LA whose link status has changed in step S3
When the N port is the monitoring target (Yes), it is determined whether the change in the link status is up.

This can of course be done by notifying that the link state is up or down from the LAN port. S5. If the change in the link status is up (Yes) in step S4, the connection management table is updated to reflect the change in the link status in the connection management table.

S6. The link status in the connection management table is searched to determine whether there is another LAN port whose link status is up. If there is another LAN port whose link status is up (Yes), power is already supplied to the common device and the power supply should not be stopped, so the processing is temporarily terminated.

S7. In step S6, when there is no other LAN port whose link status is up (No), a timer is started and the change of the link status is monitored for a predetermined time. S8. It is determined whether or not the link status has changed during the predetermined time. This is possible with the same monitoring as already explained.

When the link status has changed (Yes)
Requires checking the type of the port that has changed and determining whether there is a change in the monitoring target and whether the change is up or down, so jump to step S2 and continue the subsequent processing. To do. S11. If there is no change in the link status in step S8 (No), the other LAN up in step S6.
Since it is necessary to supply power to the printer because there is no port, power is supplied to the printer by controlling the contact control circuit.

S12. Since the client under its control has been up for the first time, the upper hub is notified that there is an up LAN port, and the processing ends. Step S1
The processes of 1 and S12 are processes performed when the connection management table transits from the state of FIG. 8 to the state of FIG. S13. On the other hand, in step S4, when the change in the link state is down (No), the connection management table is updated to reflect the change in the link state in the connection management table.

S14. In this state, it is determined by referring to the connection management table whether the link states of all LAN ports are down. LA not down in this state
If there is an N port (No), there is another client whose link status is up and the power supply should not be stopped, so the processing ends without doing anything.

S15. In step S14, all LANs
When the link status of the port is down (Yes), a timer is started to monitor the change of the link status for a predetermined time. S16. It is determined whether or not the link status has changed during the predetermined time. This is possible with the same monitoring as already explained.

When the link status has changed (Yes)
Requires checking the type of the port that has changed and determining whether there is a change in the monitoring target and whether the change is up or down, so jump to step S2 and continue the subsequent processing. To do. S19. If there is no change in the link status in step S16 (No), it is necessary to stop the power supply to the printer together with the link status of all LAN ports being down in step S14. The contact control circuit is controlled to stop the power supply to the printer. S20. Since all the clients under its control are down, the upper hub is notified that all the LAN ports are down, and the process is terminated.

The processes of steps S19 and S20 are processes when the connection management table transits from the state of FIG. 9 to the state of FIG. By controlling the power supply as described above, the power supply to the printer is stopped when the link status of all clients is down, and the power is reliably supplied to the printer when the link status of one client is up. As a result, useless electric energy is not consumed, and power can be accurately supplied when necessary.

FIG. 11 is a flow chart showing the operation of the power supply control unit common to the independent / dependent hubs. After that, FIG.
The operation of the power supply control unit common to independent hubs / dependent hubs will be described with reference to symbols. S1. The central processing unit monitors whether there is a change in the link status of the LAN port and determines whether there has been a change.

This can be done by monitoring the link status up or down notification from the LAN port.
When there is no change (No), the above monitoring and determination are continued. S2. In step S1, if the link status has changed (Yes), the type of the LAN port that has changed is confirmed.

This is because the central processing unit can refer to the connection management table and confirm the LAN port type by adding the address of the LAN port when the link status is notified of up or down. Become. S3. It is determined whether or not the LAN port whose link status has changed is a monitoring target. This can be done by referring to the connection management table by using the notified address as a key by the central processing unit.

If the LAN port whose link status has changed is not the monitoring target (No), the process is temporarily terminated. S4. LA whose link status has changed in step S3
When the N port is the monitoring target (Yes), it is determined whether the change in the link status is up.

This can of course be done by notifying the LAN port of whether the link state is up or down. S5. If the change in the link status is up (Yes) in step S4, the connection management table is updated to reflect the change in the link status in the connection management table.

S6. The link status in the connection management table is searched to determine whether there is another LAN port whose link status is up. If there is another LAN port whose link status is up (Yes), power is already supplied to the common device and the power supply should not be stopped, so the processing is temporarily terminated.

S7. In step S6, when there is no other LAN port whose link status is up (No), a timer is started and the change of the link status is monitored for a predetermined time. S8. It is determined whether or not the link status has changed during the predetermined time. This is possible with the same monitoring as already explained.

When the link status has changed (Yes)
Requires checking the type of the port that has changed and determining whether there is a change in the monitoring target and whether the change is up or down, so jump to step S2 and continue the subsequent processing. To do. S9. In step S8, if there is no change in the link state (No), it is determined whether the hub is set as an independent hub.

This can be done by checking whether the setting switch is the ground voltage or the power supply voltage. S10. If the setting is independent hub in step S9 (Yes), it is necessary to supply power to the printer together with the fact that there is no other LAN port up in step S6. Therefore, the contact control circuit is controlled. Then, the power supply to the printer is started and the processing is ended.

This is the operation when one client is up in the configuration of FIG. S11. If the setting is a subordinate hub in step S9 (No), it is necessary to supply power to the printer together with the fact that there is no other LAN port up in step S6. Therefore, the contact control circuit is controlled. Then, the power supply to the printer is started.

S12. Since the client under its control has been up for the first time, the upper hub is notified that there is an up LAN port, and the processing ends. Step S1
The processes of 1 and S12 are processes performed when the connection management table of the subordinate hub transits from the state of FIG. 8B to the state of FIG. 9B. S13. On the other hand, in step S4, when the change in the link state is down (No), the connection management table is updated to reflect the change in the link state in the connection management table.

S14. In this state, it is determined by referring to the connection management table whether the link states of all LAN ports are down. LA not down in this state
If there is an N port (No), there is another client whose link status is up and the power supply should not be stopped, so the processing ends without doing anything.

S15. In step S14, all LANs
When the link status of the port is down (Yes), a timer is started to monitor the change of the link status for a predetermined time. S16. It is determined whether or not the link status has changed during the predetermined time. This is possible with the same monitoring as already explained.

When the link status has changed (Yes)
Requires checking the type of the port that has changed and determining whether there is a change in the monitoring target and whether the change is up or down, so jump to step S2 and continue the subsequent processing. To do. S17. In step S16, if there is no change in the link status (No), it is determined whether the setting is an independent hub.

S18. If the setting is independent hub in step S17 (Yes), it is necessary to stop the power supply to the printer together with the link status of all LAN ports being down in step S14.
The contact control circuit is controlled to stop the power supply to the printer, and the process ends. This is the operation when all the clients are down in the configuration of FIG.

S19. If the setting is the subordinate hub in step S17 (No), it is necessary to stop the power supply to the printer together with the fact that the link states of all the LAN ports are down in step S14. The contact control circuit is controlled to stop the power supply to the printer. S20. Since all the clients under its control are down, the upper hub is notified that all the LAN ports are down, and the process is terminated.

The processes of steps S19 and S20 are processes when the connection management table of the subordinate hub transits from the state of FIG. 9B to the state of FIG. 8B. By controlling the power supply as described above, the power supply to the printer is stopped when the link status of all clients is down, and the power is reliably supplied to the printer when the link status of one client is up. As a result, useless electric energy is not consumed, and power can be accurately supplied when necessary. Moreover, since the common processing function can be given to the independent hub and the dependent hub and the processing can be selectively performed according to the setting, it is not necessary to install different software for the independent hub and the dependent hub. , The hub manufacturing can be streamlined.

Note that in FIGS. 8, 9, 10 and 11, the adjacent hubs are treated in the same way as the clients, so when one client is up in the lower hub as seen from the upper hub, Even if all connected clients are down, the power of the printer is turned on, but by removing the lower hub from the monitoring target, when all the clients connected to itself are down, the lower hub It is not necessary to power on the printer connected to itself when one client comes up. However, to apply the above control, it is necessary to provide a dedicated printer in the lower hub.

Further, the power supply of the server is not controlled consistently. This is because the server is connected to a LAN system higher than the LAN system having the configuration shown in FIG. 1 or 2, and in many cases, programs and data are down-loaded regardless of client up / down. This is because it is assumed. Therefore, in the case of a stand-alone LAN system in which the server is not connected to the upper LAN system, the server power supply can be controlled. In this case, it is preferable to store the types in the connection management table without distinguishing the types of the server and the printer.

Finally, by realizing the power supply control system as shown in FIG. 3 and providing it to the hub, the construction and operation of the LAN system can be rationalized. In the above, the system to which the server and the client are connected is the hub, but the device to which the server and the client are connected is not limited to the hub when constructing the LAN system. Is added.

[0089]

As described above in detail, according to the present invention, it is possible to connect a LAN device having a plurality of LAN ports to the LAN device.
The present invention relates to a power control method for a common device that receives power from an AN device, and in particular, the power supply to the common device is manually performed based on the result of detection of a change in the link state with a client connected to the LAN device. It is possible to realize a power supply control method for a common device that can be controlled without using the control.

That is, according to the first invention, the link state between the LAN device and the client connected to the LAN port is detected, and when the link is formed with at least one client, the link state is detected. Power is supplied to the common device connected to the power port, and when no links are formed with all clients, the power supply to the common device connected to the power port is stopped. The common device connected to the port does not consume unnecessary electric energy, and power is supplied to the common device connected to the power supply port when there is at least one client with which a link is formed. can do.

Further, according to the second invention, the link state between the LAN device and the client connected to the LAN port is detected, and when the link is formed with at least one client, the link state is detected. Power is supplied to the common device connected to the power port, and the upper LAN
Information to the effect that a link is formed in the LAN device is sent to the device, and power is supplied to the common device connected to the power port when no link is formed with all clients. Since the information indicating that the link is not formed in the LAN device is sent to the upper LAN device at the same time as the stop,
The power supply of the common device connected to the device can be accurately controlled, and the power supply of the common device connected to the upper LAN device can also be accurately controlled.

According to the third aspect of the invention, the power supply control method for the LAN device of the first aspect of the invention and the LA of the second aspect of the invention are used.
Since it is possible to switch the power control method of the N device, one of the function obtained by the first invention and the function obtained by the second invention can be selected, and the independent LA
It is possible to commonly apply to the N device and the subordinate LAN device.

According to the fourth aspect of the invention, since the protection time is set before the power supply to the common device is started and before the power supply to the common device is stopped, the start of the power supply is determined. After that, or after determining that the power supply has been stopped, hunting of power on and power off does not occur even if the link state changes, and power control can be stabilized.

Further, according to the fifth invention, the LAN device is a power supply control system in the LAN device of the first invention, or a power supply control system in the LAN device of the second invention, or the third device. Since any one of the power supply control methods in the LAN device of the present invention is applied, the power supply control of the common device connected to the LAN device or the higher LAN
It becomes possible to accurately control the power supply of the common device connected to the device.

As a result, regardless of whether the LAN system has a single layer or a plurality of layers, it is possible to properly operate the LAN system and prevent unnecessary electric energy consumption in the LAN system.

[Brief description of drawings]

FIG. 1 is a configuration example (1) of a LAN system.

FIG. 2 is a configuration example (2) of a LAN system.

FIG. 3 is a configuration of a hub focusing on a power supply control unit.

FIG. 4 is a structure of a connection management table.

5 is an example of stored information (1) in a connection management table of a hub in the system configuration of FIG.

FIG. 6 is an example of storage information of a hub connection management table in the system configuration of FIG. 1 (No. 2).

FIG. 7 is a flowchart showing the operation of the power supply controller of the independent hub.

8 is an example (1) of stored information of a connection management table of each hub in the system configuration of FIG.

9 is an example (2) of stored information in a connection management table of each hub in the system configuration of FIG.

FIG. 10 is a flowchart showing the operation of the power supply control unit of the subordinate hub.

FIG. 11 is a flowchart showing an operation of a power supply control unit common to independent / dependent hubs.

[Explanation of symbols]

1 Independent hub 1a Subordinate hub 2 server # 1 3 Printer # 1 3a Printer # 2 4 Client # 1 4a Client # 2 4b Client # 3 4c Client # 4 4d client # 5 4e Client # 6 11 Power control unit 11-1 Central control unit (CPU) 11-2 bus 11-3 Contact control circuit 11-4 timer 11-5 Connection management table 11-6 switch 11-7 Commercial AC input outlet PIN 12 Power port P # 1 12a Power port P # 2 13 LAN port L # 1 13a LAN port L # 2 13b LAN port L # 3 13c LAN port L # 4 13d LAN port L # 5

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5B011 EA02 FF04 KK03 MA12                 5K033 AA00 DA15 DB25

Claims (5)

[Claims] 1. A power supply control method in a LAN device comprising a plurality of LAN ports and a plurality of power supply ports for supplying power to a common device forming a LAN, the power supply control system being connected to the LAN device via the LAN port. It detects the link status with other clients, supplies power to the common device connected to the power port when a link is formed with at least one client, and connects with all clients. A power control method for a LAN device, characterized in that power supply to a common device connected to the power port is stopped when a link is not formed. 2. A power supply control method for a LAN device comprising a plurality of LAN ports and a plurality of power supply ports for supplying power to a common device forming a LAN, wherein the LAN device is connected via the LAN port. A link state with a connected client is detected, and when a link is formed with at least one client, power is supplied to a common device connected to the power port and a higher LAN device is connected. To the relevant LAN device, the information indicating that a link has been formed is transmitted to the LAN device, and when no links have been formed with all clients, power supply to the common device connected to the power supply port is stopped. In addition, the LA that transmits information to the upper LAN device that the link is not formed in the LAN device. N device power control system. 3. A power control method for a LAN device, comprising: a plurality of LAN ports; and a plurality of power ports for supplying power to a common device forming the LAN, the power control method for the LAN device according to claim 1. , Claim 2
A power control method for a LAN device, wherein the power control method for the LAN device is switched. 4. The power control method for a LAN device according to claim 1, before starting the power supply to the common device and before stopping the power supply to the common device. A power control method for a LAN device, which is characterized by providing a protection time. 5. A power control system for a LAN device according to claim 1, or a power control system for a LAN device according to claim 2.
Alternatively, a LAN device to which any one of the power control methods for a LAN device according to claim 3 is applied.