JP2002335262A - Switching hub and method for its power-saving - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a switching hub that controls the operating frequency of its part circuitry to conduct supply of minimum supply of required current and heat generation control thereby reducing the running cost and noise and to provide a method for its power-saving. SOLUTION: The switching hub is configured with a circuit section depending on number of ports such as a protocol processing section 3, a coding section 4, a decoding section 5, a transmission circuit section 6, a reception circuit section 7, and a physical control section 11; a common circuit section such as a cross bus switch section 1, a packet memory section 2 and a forwarding/ queue control circuit section 10, and a frequency control circuit section 8 and a VCO circuit section 12. The reception circuit section 7 discriminates the operating state of each port and allows the frequency control circuit section 8 to decrease the operating frequency supplied from the VCO circuit section 12 as its control when there exists ports not in use. Thus, the switching hub can be operated with required minimum power without waste, the power consumption can effectively be utilized, heat generation is reduced, EMI(electromagnetic interference) is decreased and the operation stable margin can be strengthened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a switching hub having a plurality of connection ports and relaying data between information devices connected to a network, and a power saving method thereof.

[0002]

2. Description of the Related Art Hitherto, LAN components such as a LAN switch and a switching hub have to be constantly supplied with power for maintenance of a network.

[0003]

However, as the number of ports actually used and the bandwidth capacity become more variable as the size of the device becomes larger, the margin from the maximum configuration required in the full bandwidth becomes higher. In other words, there is a problem that a wasteful use environment is unavoidable in actual operation.

The present invention provides a switching hub and a switching hub for controlling daily operating costs and noise due to excessive rotation of a fan by controlling the operating frequency of a part of the circuit to control the minimum necessary current supply and heat generation. The main purpose is to provide a power saving method.

[0005]

According to a first aspect of the present invention, there is provided a switching hub having a plurality of ports, based on a data reception state from a connection destination via the plurality of ports. Determining means for determining the use status of each port, and collecting information on all ports determined to be in use by the determining means, and determining all ports in use based on the collected information. The load of the port is detected, and the ratio of the detected load to the maximum load when a plurality of ports are all in use is calculated,
It is characterized by having control means for controlling the operating frequency based on the calculated ratio, and supply means for supplying the operating frequency controlled by the control means.

According to a second aspect of the present invention, in the first aspect of the present invention, the judging means judges the use status of the port based on whether or not the clock component is continuously extracted from the data signal for an arbitrary time. It is characterized by doing.

According to a third aspect of the present invention, in the first aspect, the determining means has a physical control unit for confirming validity of a packet received from a connection destination, and the physical control unit determines that the packet is valid. If the port is in use, it is determined that the port is not in use.

[0010] According to a fourth aspect of the present invention, in the first aspect of the invention, the judging means is configured to receive the next received from the connection destination.
A physical control unit for confirming the page information, wherein the port is in use when the Next-page information is a message indicating connection in the physical control unit, and the port is not in use when the message indicates release; It is characterized by determining.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the supply means operates when the determination means determines that all of the plurality of ports are not in use. The frequency supply is stopped.

According to a sixth aspect of the present invention, in the first aspect of the present invention, the supply means sets the operating frequency controlled by the control means to a cross bus switch section, a forwarding / queue It is supplied to the control circuit section and the packet memory section.

According to a seventh aspect of the present invention, there is provided a power saving method for a switching hub having a plurality of ports, wherein a judging step of judging a use state of each of the plurality of ports, and judging that the ports are in use by the judging step. Aggregation process to aggregate the information of the ports that have been collected, a detection process to detect the load of all the ports in use aggregated by the aggregation process, and the maximum load when multiple ports are all in use A calculating step of calculating a load ratio of all ports in use detected by the detecting step, a control step of controlling an operating frequency based on the load ratio calculated by the calculating step, and a control step. And supplying the operating frequency to a predetermined circuit.

According to an eighth aspect of the present invention, in the seventh aspect of the present invention, the determining step determines that each of the plurality of ports is in use when carrier detection from a connection destination continues for a predetermined time. If it does not continue for a predetermined time, it is determined that it is not in use.

According to a ninth aspect of the present invention, in the invention of the seventh aspect, when the packet is received from the connection destination at each of the plurality of ports, the validity of the packet is confirmed, Is determined to be in use when determined to be, and is determined to not be used when determined to be invalid.

According to a tenth aspect of the present invention, in the invention of the seventh aspect, when the next-page information is received from the connection destination at each of the plurality of ports, the next-page information is transmitted. The use state of each port is determined by confirming.

[0015] The invention of claim 11 provides the invention according to claims 7 to 1
0, In the invention according to any one of 0, the supply step is:
When the determination step determines that all of the plurality of ports are not in use, the supply of the operating frequency to the predetermined circuit is stopped.

<Operation> In the switching hub of the present invention, the receiving circuit unit is provided with a function of detecting the alive state of the communication partner, and an algorithm for optimizing the operating frequency of the specific circuit according to the situation of each circuit is provided.
Power supply and control to minimize heat generation by optimizing the operating frequency.

According to the present invention, a transmitting circuit unit, a receiving circuit unit,
The configuration includes a circuit unit that depends on the number of port interfaces such as an ENCODER, a DECODER, and a protocol processing unit, and a circuit unit such as a forwarding / queue control circuit unit, a packet memory unit, and a cross bus switch unit. Here, the load on the commonly required circuit unit is proportional to the number of used ports of the circuit unit depending on the port interface.

According to the present invention, the usage status of each port is determined, and if there is an unused port, the operation of the common circuit section (forwarding / queue control circuit section, packet memory section, cross bus switch section) is performed. It has a control function to reduce the frequency and stop unnecessary high-speed operations. Therefore, the operation can be performed with the minimum necessary power without waste, the power consumption can be effectively utilized, and the effects of reducing heat generation, reducing EMI (electromagnetic interference), and enhancing the stability margin of operation can be obtained. Is obtained.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a switching hub and a power saving method thereof according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. 1 to 5 show an embodiment of a switching hub and a power saving method thereof according to the present invention.

<First Embodiment> FIG. 1 shows a first embodiment of the present invention.
FIG. 3 is a block diagram showing a schematic configuration in a case where the switching hub according to the embodiment is applied to a LAN using an input buffer method or an output buffer method. In FIG.
The switching hub according to the embodiment of the present invention includes a cross bus switch unit 1, a packet memory unit 2, a protocol processing unit 3, an encoding unit 4, a decoding unit 5, and a transmission circuit unit 6.
, A reception circuit unit 7, a frequency control circuit unit 8, a cable 9, a forwarding / queue control circuit unit 10, a physical control unit 11, and a VCO circuit unit 12.

The receiving circuit unit 7 has a function of detecting data (carrier) from a partner (communication destination) connected by a cable 9 or an optical fiber on the LAN interface, and extracts a clock component from the received carrier. Then, the signal is distributed as a clock source of each related circuit unit, and the data is passed to the decoding unit 5. Originally, data on the cable 9 is used to enhance noise resistance, efficiently transmit high-speed signals,
Since various signal processes have been performed from the viewpoint of MI countermeasures and the like, these are canceled by the decoding unit 5.

Subsequently, the received data is analyzed and translated in a protocol specific to the LAN by the protocol processing unit 3.
Recognition of a transfer address, removal of an unnecessary header, and error checking are performed. Thereby, the data is converted into a simple format suitable for transfer inside the switching hub.

The data converted by the protocol processing unit 3 is temporarily stored in the packet memory unit 2 via the forwarding / queue control circuit unit 10. The stored data is transferred to the forwarding / queue control circuit 10
Read at any time by queue management controlled by
The port is exchanged with the destination port via the cross bus switch unit 1. The data is temporarily stored in the packet memory unit 2 in order to match when the transfer speeds of the port interfaces are different, to wait for the vacancy of the cross bus switch unit 1, and to perform transfer processing from the data with the highest priority. Buffering is the purpose.

In the first embodiment of the present invention, the case of the switching system having the packet memory unit 2 on the input side or the output side is shown. On the other hand, the transmitting side transmits the exchanged data to the LAN
Then, the packet is converted into a signal form suitable for high-speed and long-distance transmission by the encoding unit 4, and data is output from the transmission circuit unit 7 to the connection partner via the cable 9 or the optical fiber.

When receiving circuit section 7 receives data from the connection partner, it sends a partner alive signal to frequency control circuit section 8. The frequency control circuit unit 8 receives the partner alive signals from the reception circuit units 7 of all the ports, recognizes the number of ports that are actually in use (in an active state), and then determines the number of ports that are the common circuit unit. The load factor is calculated in comparison with the maximum load applied to each of the bus switch unit 1, the packet memory unit 2, and the forwarding / queue control circuit unit 10, and the operating frequency within which the processing is not lost is determined. In other words, by setting the minimum required operating frequency, unnecessary resource consumption is prevented without deteriorating performance.

The partner alive signal from the receiving circuit 7 is always detected, and the frequency control circuit 8 always optimizes the operating frequency of the common circuit. In addition, general L
In the AN, as long as the connection partner is connected, a signal for synchronization always flows even if there is no data signal. The receiving circuit unit 8 has a clock recovery function for extracting a clock component from the data signal or the synchronization signal. Have. It is effective to utilize this clock recovery signal as a partner alive signal.

FIG. 2 is a flowchart showing an operation example of the switching hub according to the embodiment of the present invention. First,
The receiving circuit unit 7 is configured to always detect a transmission signal including a synchronization signal from a connection partner via the cable 9. Once the reception circuit unit 7 detects the reception carrier from the partner for each port connected on the cable 9 (step S1), the reception circuit unit 7 synchronizes the signal with the synchronization signal or data signal (reception carrier) to synchronize with the reception carrier. The components are extracted (step S2). Therefore, it is possible to use the means for detecting the carrier based on the presence or absence of the clock extraction. If it is confirmed that the carrier detection continues for a predetermined time arbitrarily set in advance (step S3 / YES), the connection partner is in the alive state (the port is in use), the transmission quality of the cable 9 is good, and the communication preparation is completed. We can recognize that it is in place.

The frequency control circuit unit 8 collects information on all port statuses (step S4), and compares the load on the common circuit unit with the maximum load based on a preset algorithm. The ratio (load ratio) is calculated, and the frequency is optimized (step S6). This load factor is
A frequency proportional to the analog potential transmitted to the VCO circuit unit 12 as an analog potential and input by the VCO circuit unit 12 is supplied to the common circuit unit (step S7).
The output to the common circuit section always linearly and dynamically fluctuates with respect to the input.

Although the carrier detection of the connection partner in the receiving circuit unit 7 is always performed, if the carrier detection is interrupted once and the clock component extraction is interrupted for a certain period of time or more (step S3 / NO), the load for the port is loaded. When the information is excluded from the calculation target, that is, only information on all the port statuses in use is collected (step S5), and the load on the common circuit unit is compared with the maximum load based on a preset algorithm. Is calculated and the frequency is optimized (step S6). This new load factor is transmitted to the VCO circuit unit 12 as an analog potential, and a frequency proportional to the analog potential input by the VCO circuit unit 12 is supplied to the common circuit unit (step S7).

As described above, the receiving circuit unit 7 always detects the received carrier on the cable 9, and the frequency control circuit unit 8 always calculates the required load factor according to the reception state, and converts this load factor into an analog signal. The potential is output to the VCO circuit unit 12. The VCO circuit unit 12 provides a frequency proportional to the analog potential (load factor) input from the frequency control circuit unit 8 to the common circuit unit, and operates the common circuit unit, for example, the packet memory unit 2 and the cross bus switch unit. 1. The bus transfer operation and the like by the forwarding / queue control circuit unit 10 are controlled based on the frequency.

Further, when there is no alive information of the connection partner for all the ports, that is, when all the connected ports are not in use, the input from the frequency control circuit 8 to the VCO circuit unit 12 is set to zero. By doing so, the operation of the common circuit unit is stopped, which is more effective from the viewpoint of resource protection.

The connection partner has a test sequence for establishing a link before transmitting information data, or as a signal for synchronization even after the link is established, for example, a preamble of 8 bytes in Ethernet (registered trademark). Since the signal is transmitted, if the common circuit unit rises to the required operating frequency within these time ranges, the actual data packet will not be dropped. Even if this may not be enough, it can be said that there is no substantial adverse effect because the retransmission process is performed by the upper layer protocol on the connection partner side.

In the first embodiment of the present invention, the clock signal extracted from the received carrier is used as the alive signal of the connection partner, so that the conventional LA is used.
The present invention can be easily realized without major changes or modifications to the configuration of the N circuit.

<Second Embodiment> The basic configuration of a second embodiment of the present invention is the same as that of the above-described first embodiment of the present invention. The case where another method is used will be described below.

FIG. 3 is a block diagram showing a schematic configuration when a switching hub according to a second embodiment of the present invention is applied to a LAN using an input buffer system or an output buffer system. In the second embodiment of the present invention, as a function of detecting alive information of a connection partner, a Wake-up packet such as a magic packet is used. FIG. 4 is a flowchart showing an operation example at that time.

Wake-u using a magic packet as an example
The p-packet is a packet that pre-defines exchange when it is desired to give a connection partner some sort of trigger, such as, for example, remotely turning on power using a network. This Wake-up packet is a packet understood by simple pattern recognition at the physical layer level by the physical control unit 11 without passing through the protocol processing unit 3. In the second embodiment of the present invention, the frequency control circuit 8 is operated with the wake-up packet as a trigger.

The physical control unit 11 detects a Wake-up packet from the connection partner and the content (validity)
Check. The receiving circuit unit 7 has a clock recovery function of extracting a clock component from a synchronization signal or a data signal in order to synchronize with the carrier once detected on the cable 9 from the connection partner.

Here, when a reception carrier from the connection partner is detected for a certain period of time, an electrical connection state can be established at this time, but it is not in a communicable state yet. Further, when the connection partner needs a connection with the switching hub, it transmits a Wake-up packet. Receiving circuit section 7
The Wake-up packet received at is decoded by the decoding unit 5 and is taken into the physical control unit 11. Here, matching with a predetermined pattern is performed, and Wake-u
If the validity of the p packet is confirmed, it can be recognized that the connection partner is in the alive state, the transmission quality of the cable 9 is good, the communication is ready, and there is a data communication request from the connection partner. The result of this judgment is
It is transmitted to the frequency control circuit section 8 and controls the VCO circuit section 12 to optimize the operating frequency to the common circuit section.

When the connection partner wants to notify the end of the communication request, the connection partner transmits a predetermined Sleep packet to the switching hub, and the Wake-u
Similar to the p packet, the frequency control circuit unit 8 recalculates the optimum frequency to the common circuit unit by subtracting the load related to the corresponding port by collation of the physical control unit 11 and VC
The value is passed to the O circuit unit 12.

As described above, the physical control unit 11 always detects a special packet, and the frequency control circuit unit 8 performs an optimal frequency calculation according to the state. Further, when a Sleep packet is detected for all ports, it is more effective to stop the frequency to the common circuit unit which does not depend on the port.

<Third Embodiment> FIG. 6 shows a third embodiment of the present invention.
10 is a flowchart showing an operation example of the switching hub according to the embodiment of the present invention, and Next-Pag in an auto-negotiation sequence of Ethernet (registered trademark).
This shows processing when e information is used.

Next-Page information is a group of pulses for communication between links, and is followed by a base page used to predetermine connection modes such as transmission speed and half-duplex / full-duplex between partners. What is sent. The contents can be freely defined individually depending on the vendor or the device. Using this, a specific signal group is actually used as a trigger, and the agreement is recognized between the connected partners. This N
Since the ext-Page information is recognized by the physical control unit 11, Wake used in the second embodiment of the present invention.
-It can be realized with the same flow as the up packet.

The advantage of using the Next-Page information is that the exchanged signals can be arbitrarily determined as long as they can be mutually recognized beforehand. Wake-up, Sl
A signal other than the signal for controlling the eep can be defined, and various commands can be issued to the frequency control circuit. For example, set the time until communication,
Operation frequency when the circuit becomes heavily loaded, such as making the frequency fluctuation wait until just before the start, lowering the operation frequency when detecting abnormal temperature in combination with the temperature sensor, or transmitting at full rate. Can be customized according to the surrounding environment and changes, such as a higher supply.

In these methods, in addition to the effects of the above-described embodiment, since the connection partner's intention information such as a Wake-up packet and Next-Page information from the connection partner is added to the frequency control judgment material, the frequency supply is not required. This has the advantage that the conditions are more defined. For example, if the judgment criterion has a specific hysteresis, incorrect judgments caused by noise and floating bias on the transmission line can be eliminated, and there is no meaning such as ringing of frequencies that tend to occur in an environment where transmission quality is unstable. Continuation can be avoided. Therefore, appropriate frequency control and power saving control can be performed by preventing the effects of useless operations and malfunctions. Further, by combining these embodiments, fine power control can be performed.

[0045]

As is apparent from the above description, according to the present invention, it is determined whether or not communication is possible according to the presence or absence of a connection partner or the state of the connection partner and the cable transmission quality. Power is supplied to the common circuit only for a certain time.Therefore, if there is no connection partner or communication is not possible, or if communication is difficult due to deterioration of the quality of the transmission line, unnecessary circuit power Supply can be kept to a minimum and wasteful consumption can be avoided.

Further, according to the present invention, since control can be performed on a port basis and detailed responses can be made, an optimum environment can be provided even when the situation of the connection partner constantly fluctuates. As a whole, the reduction of steady power consumption increases the margin for thermal design, and eliminates or reduces cooling parts such as fins, heat sinks, and fans, which are expensive and physically restricted. To contribute.

Further, according to the present invention, since only the minimum necessary circuits are operated, unnecessary radiation noise is reduced, and the number of steps for EMI countermeasures and the cost of parts are greatly reduced. By reducing such noise, adverse effects such as interference on the circuit itself can be eliminated.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a switching hub according to a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating a processing example of a switching hub according to the first embodiment of the present invention.

FIG. 3 is a block diagram illustrating a schematic configuration of a switching hub according to second and third embodiments of the present invention.

FIG. 4 is a flowchart illustrating a processing example of a switching hub according to a second embodiment of the present invention.

FIG. 5 is a flowchart illustrating a processing example of a switching hub according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cross bus switch part 2 Packet memory part 3 Protocol processing part 4 Encoding part 5 Decoding part 6 Transmission circuit part 7 Receiving circuit part 8 Frequency control circuit part 9 Cable 10 Forwarding / queue control circuit part 11 Physical control part 12 VCO circuit part

Claims (11)

[Claims] 1. A switching hub having a plurality of ports, a determining unit for determining a use state of each port based on a reception state of data from a connection destination via the plurality of ports, Aggregate information of all ports determined to be in, detect the load of all ports determined to be in use based on the aggregated information,
A control unit that calculates a ratio of the detected load to a maximum load when all of the plurality of ports are in use, and controls an operation frequency based on the calculated ratio; And a supply means for supplying the operating frequency. 2. The apparatus according to claim 1, wherein the determination unit determines the use status of the port based on whether or not a clock component is continuously extracted from the data signal for an arbitrary time. Switching hub. 3. The determination unit has a physical control unit that checks the validity of a packet received from the connection destination. If the physical control unit determines that the packet is valid, the port is in use. 2. The switching hub according to claim 1, wherein if not appropriate, it is determined that the port is not in use. 4. The determination means has a physical control unit for confirming Next-page information received from the connection destination, and when the Next-page information is a message indicating a connection in the physical control unit, The port is in use,
2. The switching hub according to claim 1, wherein it is determined that the port is not in use in the case of a message indicating the release. 5. The apparatus according to claim 1, wherein the supply unit stops supplying the operating frequency when the determination unit determines that all of the plurality of ports are not in use. 2. The power saving method for a switching hub according to claim 1. 6. The supply unit supplies the operating frequency controlled by the control unit to a cross bus switch unit, a forwarding / queue control circuit unit, and a packet memory unit. Item 6. The switching hub according to any one of Items 1 to 5. 7. A power saving method for a switching hub having a plurality of ports, comprising: a determining step of determining a use state of each of the plurality of ports; A counting step of collecting information; a detecting step of detecting the loads of all the ports in use that are collected by the counting step; and a maximum load when the plurality of ports are all in use. A calculating step of calculating a load ratio of all the ports in use detected by the detecting step; a control step of controlling an operating frequency based on the load ratio calculated by the calculating step; Supplying the operating frequency controlled by the process to a predetermined circuit. 8. The determining step determines that the carrier is being used when the carrier detection from the connection destination continues for a predetermined time in each of the plurality of ports, and determines that the port is not used when the carrier detection from the connection destination does not continue for a predetermined time. The power saving method for a switching hub according to claim 7, wherein 9. The method according to claim 1, wherein, when each of the plurality of ports receives a packet from a connection destination, the validity of the packet is checked, and if the packet is determined to be valid, it is determined that the packet is being used. 8. The power saving method for a switching hub according to claim 7, wherein if it is determined that the switching hub is not in use, it is determined that the switching hub is not in use. 10. The method according to claim 1, wherein the determining step includes: determining a Nex from a connection destination in each of the plurality of ports.
When the t-page information is received, the next-page
8. The power saving method for a switching hub according to claim 7, wherein the usage status of each port is determined by confirming the ge information. 11. The supply step stops supply of an operating frequency to the predetermined circuit when it is determined in the determination step that all of the plurality of ports are not in use. 11. The power saving method for a switching hub according to any one of items 1 to 10.