JP2008219480A - Network device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To balance guarantee of an operation and rationalization of power capability of a network device. <P>SOLUTION: Network devices 10a, 10b are provided with switches S1, S2 in addition to functional structure such as logic circuits L1, L2, power sources P1, P2, redundant power sources P11, P21 and communication parts C1, C2. When there is a margin in power of the network device 10a and there is not margin in power of the network device 10b, the power source P1 is connected to the communication part C1 by the switch S1 and the power is supplied from the network device 10a to the network device 10a via a network cable CV. At this time, in the network device 10b, the power source P2 is connected to the communication part C2 by the switch S2. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a network device connectable to a network.

  Network devices connected to a network via a network cable, such as routers, modems, servers, and network storages have been put into practical use. Among these network devices, particularly network devices used for commercial use are required to operate stably. In order to meet this demand, the power source used for the network device is designed to have a sufficient power supply capability even for the maximum load. Further, in order to cope with power failure or the like, the power supply of the network device is generally made redundant.

JP 2004-38331 A

  However, in general, since the efficiency of the power supply is maximized in the vicinity of the maximum capacity, each power supply may not be used efficiently due to the redundancy of the power supply. Further, the redundancy of the power supply is one of the factors that hinder the cost reduction of each network device. Furthermore, the power supply capability is sufficiently guaranteed when viewed from the whole network system to which a plurality of network devices are connected.

  The present invention has been made in order to solve at least a part of the above-described conventional problems, and an object of the present invention is to achieve both the guarantee of the operation of the network device and the optimization of the power supply capability.

  In order to solve the above problems, a first aspect of the present invention provides a network device connectable to a communication network via a communication line. The network device according to the first aspect of the present invention includes a power source, a logic circuit connected to the power source, and an external network device connected to the power source and connected via the communication line. A power control unit that controls transmission / reception of power between them, and a connection unit that is connected to the logic circuit and the power control unit and connects the communication line.

  According to the network device according to the first aspect of the present invention, the power control unit connected to the power source controls the power transfer with the external network device connected via the communication line. It is possible to ensure both the operation of network equipment and the optimization of power supply capacity.

  Hereinafter, a network device according to the present invention will be described based on examples with reference to the drawings.

・ Conceptual composition:
The features of the network device according to the present embodiment will be described with reference to FIGS. FIG. 1 is a conceptual functional block diagram for explaining the features of the network device according to the present embodiment. FIG. 2 is a conceptual functional block diagram for explaining a conventional network device.

  The network devices 10a and 10b according to the present embodiment shown in FIG. 1 include logic circuits L1 and L2, power supplies P1 and P2, redundant power supplies P11 and P21, and a communication unit C1, which are included in the conventional network devices 100a and 100b shown in FIG. In addition to a functional configuration such as C2, switches S1 and S2 are provided.

  In the conventional network devices 100a and 100b, the power required for the operation of the logic circuits L1 and L2 is supplied by the power sources P1 and P2 for each network device. In addition, redundant power supplies P11 and P21 are provided in preparation for the malfunction of the power supplies P1 and P2, and the operation stop of the logic circuits L1 and L2 due to the malfunction of the power supplies P1 and P2, that is, the stop of the network equipment is prevented. It was. Therefore, communication data (frame) is exchanged between the network device 100a and the network device 100b communicating with the network device 100a.

  In contrast, in the network devices 10a and 10b according to the present embodiment, the power required for the operation of the logic circuits L1 and L2 is supplied by the power sources P1 and P2 for each network device, and the network devices 10a and 10b are connected to the network devices 10a and 10b. In addition to the frame, power is exchanged with the device 10b. Specifically, for example, when there is a margin in the power of the network device 10a and there is no margin in the power of the network device 10b, the power supply P1 and the communication unit C1 are connected by the switch S1, and the network device Cb is connected via the network cable CV. The power is supplied from the network device 10a to the network device 10a. At this time, in the network device 10b, the power source P2 and the communication unit C2 are connected by the switch S2.

  Thus, by exchanging surplus power between network devices, the operation of each network device can be guaranteed, and the redundant power supplies P11 and P12 can be downsized or eliminated.

Network equipment configuration:
The internal configuration of the network device will be described with reference to FIG. FIG. 3 is a functional block diagram conceptually showing the internal structure of the network device according to this embodiment.

  The network device 10 includes a power supply 11, a DC-DC converter 12, a logic circuit 13, and a plurality of network interface units 20 to 2n. The power supply 11 is connected to the DC-DC converter 12 and the network interface units 20 to 2n via a power supply line and a ground line. The network device 10 includes, for example, network communication devices such as routers and switching hubs, network storage devices that can be connected to the network, and server computers that centrally execute various processes requested from client computers via the network.

  The DC-DC converter 12 and the logic circuit 13 are connected via a power supply line and a ground line. The logic circuit 13 and the network interface units 20 to 2n are connected via a control signal line and an input / output signal line.

  The power source 11 is an AC-DC converter that converts an alternating current supplied from an external alternating current power source into a direct current. In this embodiment, the power supply 11 converts an alternating current of 100V into a direct current of 48V. Further, it is desirable that the power source 11 be an insulated power source in order to avoid a situation in which the internal circuit is damaged when a voltage higher than a specified voltage is supplied from the outside.

  The DC-DC converter 12 is a power source for converting a relatively high voltage direct current converted by the power source 11 into a relatively low voltage direct current used for driving the logic circuit 13. Here, the power supply 11 can also convert the alternating current into a low-voltage direct current used to drive the logic circuit 13. However, in this embodiment, since power is interchanged between the network devices 10, the power supply 11 has a relatively high voltage direct current in consideration of reduction of power transmission loss and a difference in operating voltage of the logic circuit in each network device. Convert alternating current into The DC-DC converter 12 is also preferably an isolated power source in order to avoid a situation in which the logic circuit 13 is damaged when a voltage higher than a specified voltage is input.

  The logic circuit 13 is a circuit for realizing various operations required for the network device. In this embodiment, in addition to the functions provided in the conventional network device, the power for controlling the transmission and reception of power. A control unit 131 is provided.

  The network interface units 20 to 2n include switches 201 to 2n1 and communication port units 202 to 2n2, respectively. The switches 201 to 2n1 are switches for electrically connecting or disconnecting the power supply 11, the DC-DC converter 12, and the communication port units 202 to 2n2. The switches 201 to 2n1 are connected to the power control unit 131 of the logic circuit 13 via a control signal line, and are switched to either the connected state or the cut-off state in response to a control signal from the logic circuit 13. Moreover, it is desirable that the switches 201 to 2n1 have an insulating structure that prevents the current input via the communication port units 202 to 2n2 from flowing directly to the power supply 11 and the DC-DC converter 12.

  The communication port units 202 to 2n2 are physical connection ports for connecting a network cable CV, for example, a LAN cable. The communication port units 202 to 2n2 include a capacitor and an insulating structure in order to prevent the logic circuit 13 from being damaged when a signal input exceeding a specified level is received from the outside.

  A cable used as a LAN cable has four pairs of copper wires in a pair of two cores. Generally, one pair is used for data transmission, one pair is used for data reception, and the remaining two pairs are used for data transmission / reception. I can't. Therefore, in a general communication port unit, only the data transmission terminal used for data transmission and the data reception terminal used for data reception are connected to the logic circuit.

  In this embodiment, the communication port units 202 to 2n2 may include only the data transmission terminal DST and the data reception terminal DRT, or, in addition to the data transmission terminal DST and the data reception terminal DRT, for power transmission or power feeding. A power supply terminal VT and a ground terminal GT for use may be provided.

  When the communication port units 202 to 2n2 are provided with only the data transmission terminal DST and the data reception terminal DRT, the switches 201 to 2n1 are connected to the power transmission line VL and the ground line GL with respect to the data transmission terminal and the data reception terminal, respectively. Connect. In this case, power is transmitted superimposed on data on two pairs of copper wires used for data transmission and data reception. Alternatively, when the communication port units 202 to 2n2 are provided with the power supply terminal VT and the ground terminal GT in addition to the data transmission terminal DST and the data reception terminal DRT, the switches 201 to 2n1 are connected to the power supply terminal VT and the ground terminal. A power supply line VL and a ground line GL are connected to GT, respectively. In this case, power is sent independently of the data via two free pairs of copper wires.

Power supply control:
The power supply control executed in the network device 10 according to the present embodiment will be described with reference to FIGS. FIG. 4 is an explanatory diagram illustrating an example of a connection mode of a plurality of network devices according to the present embodiment. FIG. 5 is a flowchart showing a processing routine of power supply control processing executed in a network device that receives power from another network device among the network devices according to the present embodiment. FIG. 6 is an explanatory diagram illustrating an example of a power supply control management table provided in the network device according to the present embodiment. FIG. 7 is a flowchart illustrating a processing routine of power supply control processing executed in a network device that supplies power to other network devices among the network devices according to the present embodiment.

  In the following description, as shown in FIG. 4, description will be made using an example in which a mesh network in which a plurality of network devices are connected to each other is constructed. In FIG. 4, the network device that receives power from the other network device D2 is the power receiving network device D1, the other network device D2 that supplies power to the power receiving network device D1 is the power supply network device D21, and the other network device that neither receives nor supplies power D2 is represented as non-participating network device D22. Note that at least the power receiving network device D1 and the power feeding network device D21 have the same configuration as the network device 10 according to the present embodiment.

  The power supply control process executed by the power receiving network device D1 will be described with reference to FIG. When the occurrence of power shortage is detected or the occurrence of power shortage is predicted, the logic circuit 13 of the power receiving network device D1, specifically, the power control unit 131 starts this processing routine. The occurrence of power shortage or the prediction of power shortage is, for example, by monitoring power consumption with a wattmeter, or by calculating the amount of power required for executing the requested arithmetic processing required for the logic circuit 13 Can be detected.

  The power control unit 131 uses the power supply control management table shown in FIG. 6 to determine another network device D2 that can accommodate power (step S100). The power supply control management table is provided in each network device 10 according to the present embodiment, and each network device 10 is managed by using an IP address as a device name. Has items. In the example of FIG. The second network device D2 is determined as a network device capable of accommodating power.

  Each item of the power supply control management table is specified by each network device 10 according to a dedicated communication protocol or by using a function defined by a management information base (MIB) in the simple network management protocol (SNMP). Updated at timing.

  The power control unit 131 transmits a power supply request to the determined network device D2 (step S102). The power control unit 131 receives a response indicating that it can be supplied from the determined network device D2 (step S104: Yes), and in the network interface unit connected to the determined network device D2, for example, the network interface unit 20 Switch 201 is switched to the connected state. At this time, the determined network device D2 becomes the power feeding network device D21.

  If the response indicating that power can be supplied from the determined network device D2 cannot be obtained (step S104: No), the power control unit 131 returns to step S100, and another network device is selected from other network devices. Select device D2. At this time, the determined network device D2 becomes the non-participating network device D22.

  The processing procedure for receiving a response indicating that supply is possible from the determined network device D2 does not necessarily match the update timing of the power supply control management table and the transmission timing of the power supply request, and the determined network device D2 This is because the power margin may be reduced.

  The power receiving network device D1, that is, the power control unit 131 receives power supply from the power feeding network device D21 until the power shortage is resolved (step S106: No). In general, power shortage is often caused by an increase in the amount of calculation processing required for the power receiving network device D1, and the power shortage is resolved if the amount of calculation processing to be executed by the power receiving network device D1 is reduced. . When the power shortage is resolved (step S106: Yes), the power supply network device D21 is notified of the power shortage resolution (step S108), and the present embodiment is terminated.

  In the description using FIG. 5, for the sake of simplicity, the description has been given using the example of one power supply network device D21. However, it is possible to receive power supply from two or more power supply network devices D21. Needless to say. When receiving power from a plurality of power supply network devices D21, the number of power supply network devices D21 may be dynamically increased or decreased according to the amount of power that is insufficient.

  With reference to FIG. 7, the power supply control processing in the network device D2 requested to supply power from the power receiving network device D1 will be described.

  When receiving the power supply request from the power receiving network device D1 (step S200), the power control unit 131 of the network device D2 determines whether there is a margin in power (step S202). For example, as described above, the power margin may be determined with respect to the rated power using a power meter, or an operation that is being performed or is scheduled to be performed can be determined. You may calculate the electric energy required for a process.

  If the power control unit 131 determines that there is remaining power (step S202: Yes), the power control unit 131 notifies the power receiving network device D1 that power can be supplied (step S204). Specifically, a response is transmitted to the power receiving network device D1 through the network interface unit connected to the power receiving network device D1, for example, the communication port unit 2n2 in the network interface unit 2n and the network cable CV. At this point, the network device D2 becomes the power feeding network device D21.

  The power control unit 131 switches the switch 2n1 in the network interface unit 2n connected to the power receiving network device D1 to the connected state, and supplies power to the power receiving network device D1 via the network cable CV (step S206). . Specifically, as described above, it is realized by superimposing power on data using the data transmission / reception line of the network cable CV, or by transmitting only power using the empty line of the network cable CV. .

  The power control unit 131 continues power supply via the network cable CV until the power shortage in the power receiving network device D1 is resolved (step S208: No). Specifically, upon receiving a notification of power shortage resolution from the power receiving network device D1, the power control unit 131 determines that the power shortage in the power receiving network device D1 has been resolved. When the power shortage in the power receiving network device D1 is resolved (step S208: Yes), the power control unit 131 stops the power supply to the power receiving network device D1 (step S210) and ends this processing routine. Specifically, the power control unit 131 switches the switch 2n1 to the cut-off state, and releases the connection between the network cable CV, the power supply line VL, and the ground line GL.

  In step 202, when it is determined that there is no surplus power (step S202: No), the power control unit 131 notifies the power receiving network device D1 that power supply is impossible (step S212). The processing routine ends. At this point, the network device D2 becomes the non-participating network device D22.

  As described above, when a network is constructed by a plurality of network devices 10 according to the present embodiment, even if power shortage occurs in one network device 10, other network devices that have sufficient power Power can be supplied from 10 through the network cable CV. That is, the operation of the network device 10 can be ensured by allowing power to be exchanged between the network devices 10 constituting the network. Therefore, it is possible to reduce or prevent the malfunction caused by power shortage in one network device constituting the network as a whole network, and avoid and reduce the down of the entire network caused by the malfunction of one network device. can do.

  In general, conventional network devices have redundant power supplies in preparation for power shortages and power supply failures, and excessive power supplies are provided in the entire network. These excessive power supplies are used only when the power of the network device is insufficient, and a large number of power supplies with a low degree of use are provided in the entire network.

  On the other hand, according to the network device 10 according to the present embodiment, each network device 10 does not need to have a redundant power source, and each network device 10 has a minimum power source corresponding to its own processing capability. Just do it. As a result, it is possible to optimize the power supply scale in the network device, and it is possible to reduce the size and price of the network device. In general, since the power supply can operate efficiently when operating near the rated output, the operation efficiency of the power supply in each network device can be improved.

  Further, since power is exchanged via the network cable CV via the network interface unit that is always provided in the network device 10, the network device 10 does not need to be newly provided with a power supply connection terminal.

Variation:
(1) First modification:
In the above embodiment, power is supplied in response to a request from the power receiving network device D1, but power may be supplied regardless of a power supply request from the power receiving network device D1. This modification will be described with reference to FIG. FIG. 8 is a flowchart showing a processing routine in a power supply control process as a modification.

  This modification is different from the above embodiment in that power is supplied together with transmission of a frame without using a request from the power receiving network device D1 as a trigger. Therefore, no distinction is made between the power receiving network device D1 and the power feeding network device D21.

  The network device 10 starts this processing routine when a frame transmission request to another network device is generated. The power control unit 131 of the network device 10 acquires information on the network device that is the frame transmission destination. Specifically, information for determining whether or not the network device to which the frame is sent is compatible with power transfer via the network cable CV, for example, a MAC address is acquired.

  If the power control unit 131 determines that power can be supplied via the network cable CV to the network device to which the frame is sent based on the acquired information (step S302: Yes), the frame is sent. In addition, power is supplied (step S304). Specifically, as described above, the network interface unit connected to the network device to which the frame is sent, for example, the switch 201 in the network interface unit 20 is set in the connected state, and the power supply 11 and the communication port unit 202 are connected. .

  The power control unit 131 maintains the switch 201 in a connected state until transmission of all frames scheduled to be transmitted is completed (step S306: No). When the transmission of all the frames is completed (step S306: Yes), the power control unit 131 stops the power supply (step S308) and ends this processing routine. Specifically, the switch 201 is switched to the cutoff state, and the connection between the power supply 11 and the communication port unit 202 is released.

  According to this modification, power is supplied together with the frame to the network device 10 on which frame processing is executed, so that it is possible to efficiently reduce power shortage or prevent power shortage in the network device 10 on which frame processing is executed. Can be achieved. That is, in general, since the frame processing is processing in which the logic circuit 13 consumes power, the frame processing is performed without performing the exchange of the power supply request and the power supply availability notification by supplying power together with the frame. Can reduce the power shortage in the network device 10 to be used or prevent the power shortage

(2) Second modification:
In the above embodiment, the network device 10 according to the present embodiment has been described by taking a mesh network as an example, but the network device 10 can also be used in the star network shown in FIG. FIG. 9 is an explanatory diagram illustrating an example of another connection mode of a plurality of network devices according to the present embodiment.

  In the example of FIG. 9, the network device D2 is connected to the power receiving network device D1 only via the network cable CV. For example, it is useful in a system in which processing loads are concentrated on the power receiving network device D1.

(3) Third modification:
In the above embodiment, the network interface units 20 to 2n having a simple configuration have been described. However, for example, a mode in which a DC current output from the power supply 11 is supplied to another network device, power from another network device is provided. A network interface unit that adopts one of a mode in which the supply of power is received or a mode in which power is not exchanged with other network devices may be used. With reference to FIG. 10, the network interface unit 40 that can take three modes will be described. FIG. 10 is an explanatory diagram showing another configuration example of the network interface unit.

  The network interface unit 40 includes an insulated power supply 41 connected to the power supply line VL and the ground line GL, and a switch 42 connected to the ground line GL. When the switch 42 is turned on and the insulated power supply 41 is turned off, the network interface unit 40 adopts a mode in which power is supplied to other network devices via the network cable CV. The switch 42 is turned off and the insulated power supply 41 is turned on. When turned on, a mode is adopted in which power is supplied from another network device via the network cable CV. When the switch 42 and the insulated power supply 41 are turned off, the network interface unit 40 adopts a mode in which power is not exchanged with other network devices via the network cable CV.

(4) In the above embodiment, the example in which the network device 10 is applied to a so-called communication network device such as a router or a switching hub has been described. In addition, a network storage device including a large-scale storage device such as a hard disk drive or a flash memory. The present invention can also be applied to a server computer that executes various arithmetic processes in response to requests from client computers. These devices are connected via a network cable CV and have a redundant power supply. Therefore, by applying the configuration of the network device 10 according to the present embodiment, it is possible to guarantee the operation of the device and to ensure proper power supply capability. Can be achieved.

  As mentioned above, although this invention was demonstrated based on the Example and the modification, Embodiment mentioned above is for making an understanding of this invention easy, and does not limit this invention. The present invention can be changed and improved without departing from the spirit and scope of the claims, and equivalents thereof are included in the present invention.

It is a conceptual functional block diagram for demonstrating the characteristic of the network device which concerns on a present Example. It is a conceptual functional block diagram for demonstrating the conventional network apparatus. It is a functional block diagram which shows notionally the internal structure of the network apparatus which concerns on a present Example. It is explanatory drawing which shows an example of the connection aspect of the some network apparatus which concerns on a present Example. It is a flowchart which shows the process routine of the electric power supply control process performed in the network apparatus which receives electric power from another network apparatus among the network apparatuses which concern on a present Example. It is explanatory drawing which shows an example of the power supply control management table with which the network device which concerns on a present Example is provided. It is a flowchart which shows the process routine of the power supply control process performed in the network apparatus which supplies electric power with respect to another network apparatus among the network apparatuses which concern on a present Example. It is a flowchart which shows the process routine in the electric power supply control process as a modification. It is explanatory drawing which shows an example of the other connection aspect of the some network apparatus which concerns on a present Example as a modification. It is explanatory drawing which shows the other structural example of a network interface part.

Explanation of symbols

10, 10a, 10b ... Network device 100a, 100b ... Network device (conventional)
DESCRIPTION OF SYMBOLS 11 ... Power supply 12 ... DC-DC converter 13 ... Logic circuit 131 ... Power control part 20-2n ... Network interface part 201-2n1 ... Switch 202-2n2 ... Communication port part VT ... Power supply terminal VL ... Power supply line GT ... Grounding terminal GL ... ground line DST ... data transmission terminal DRT ... data reception line D1 ... power receiving network equipment D2 ... other network equipment D21 ... power feeding network equipment D22 ... non-participating network equipment CV ... network cable

Claims (6)

A network device that can be connected to a communication network via a communication line,
Power supply,
A logic circuit connected to the power source;
A power control unit that is connected to the power source and controls transmission / reception of power to / from an external network device connected via the communication line;
A network device that is connected to the logic circuit and the power control unit and includes a connection unit for connecting the communication line. The network device according to claim 1,
The power control unit further includes
A determination unit that determines an external network device that requests power transmission from among external network devices connected via the communication line;
A network device comprising a power transmission request transmission unit that transmits a power transmission request to the determined external network device. The network device according to claim 2,
The determination unit is a network device that determines an external network device that requests the power transmission using power information indicating a power state of an external network device connected via the communication line. The network device according to claim 2 or 3,
The power control unit further includes a power transmission request receiving unit that receives the power transmission request,
The power control unit is a network device that performs power transmission using the power source to an external network device that has transmitted the power transmission request. The network device according to claim 1,
The power control unit is a network device that transmits the power to an external network device to which a signal is transmitted from the logic circuit. The network device according to any one of claims 1 to 5,
The network device further includes a communication control unit that controls transmission / reception of signals to / from an external network device connected via the communication line.

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