JP2009077377A - Network relay apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for minimizing discarded frames and reducing power consumption in a network relay apparatus which conducts data transfer by using a plurality of network LSIs. <P>SOLUTION: The network relay apparatus which conducts data transfer by using the plurality of network LSIs is provided which includes a transfer engine unit having at least two network LSIs and a central control unit which controls the operation state of the network relay apparatus. The transfer engine unit includes the network LSIs capable of changing over at least one of a clock and an operation which differ every function block, a load decision unit for deciding a load laid upon each of function blocks in the network LSI, and a frequency voltage control unit for individually changing over at least one of the clock and operation voltage supplied to each function block on the basis of the load decided by the load decision unit. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a network relay device that performs data transfer, and more particularly to a network relay device that reduces power consumption.

In a backbone network of an Internet service provider or an in-house network, a network relay device that transfers frames using a plurality of network LSIs is used. In such a network relay device, conventionally, all network LSIs have been operated with a clock and an operating voltage exhibiting the maximum performance regardless of the amount of network traffic. For this reason, the network LSI cannot reduce the power consumption even if the data transfer amount is small, and causes a wasteful power consumption when the network traffic is small depending on the time zone and time.

  In Patent Document 1, system clock frequency control is performed by monitoring the connection state for each line and monitoring the flow rate of network traffic in order to reduce the power consumption of the network relay device. In Patent Document 1, a transition to a low power consumption state is made when a connection state is not detected or data communication does not occur for a long time on a network device line. In addition, system clock frequency control is performed according to the flow rate of network traffic.

JP 2003-87296 A

  However, with this method, when a sudden change occurs in the network traffic, the frame is discarded. Since current network relay devices are used as social infrastructure, it is not desirable to discard frames.

  The present invention is for solving the above-described problems, and provides a technique for minimizing frame discard and reducing power consumption in a network relay device that performs data transfer using a plurality of network LSIs. Objective.

  The present invention provides a network relay device that is connected to a plurality of lines and performs data transfer using a plurality of network LSIs. The network relay device is a network relay device having a transfer engine unit composed of at least two or more network LSIs, and a central control unit that controls the operation state of the network relay device, As a constituent element, the network LSI includes a plurality of network LSIs capable of switching at least one of a different clock and an operating voltage for each functional block that individually realizes functions in the network LSI. Further, the network LSI includes a plurality of functional blocks that realize a function for individually transferring data internally, a load applied to each functional block, a load determination unit that determines a load on the line, and the load A clock supplied to each functional block from each functional block or line load determined by the determination unit and a frequency voltage control unit that individually switches at least one of the operation voltages.

  In the network relay device of the present invention, when the load on the network LSI does not require the maximum performance, the power consumption of the network LSI is reduced by reducing at least one of the clock and the operating voltage for each functional block.

  In the network relay device, the load determination unit may determine the line load based on a reception load measurement result on the line. As one method for measuring the reception load of the network relay device, the frame length and IFG length of the immediately preceding frame are measured. Thus, since instantaneous network traffic can be measured, the maximum value of the network traffic measured within a predetermined time is assumed to be the reception load. In addition, the network relay device may perform flow control defined by IEEE 802.3x in accordance with the line processing capability when power consumption is reduced.

  In the network relay device, the central control unit analyzes a control information frame received from another network relay device or the like to determine an operation state of the line and notify the load determination unit. The load determination unit may determine the load of the line from the operation state of the line. For example, in the operation of a network relay device, a line or device that is not substantially used may be specified in a network protocol or a policy for network operation. Specifically, the Ring protocol specified in RFC 3619, STP (Spanning Tree Protocol) defined in IEEE 802.1d, VRRP (Virtual Router Redundancy Protocol) defined in RFC 2338, ALAXALA Networks GSRP (Gigabit Switch Redundancy Protocol) provided by VSRP (Virtual Switch Redundancy Protocol) provided by Foundry Networks and FVRP (Force10 VLAN Redundancy Protocol) provided by Force10 Networks are designated as standby circuits for specific lines. There are things to do. As described above, for example, a line designated as being in a standby system (that is, an operating state) can be determined to have a line load enough to transmit and receive a control information frame.

  Further, the VRRP, the GSRP, the VSRP, and the FVRP may designate the network relay device as a standby device.

  In the network relay device, paying attention to the fact that the reception load of the line is equal to the transmission load of the line of the opposite device, the opposite device of the network relay device stores the scheduled load of the transmission load in the control information frame. The network relay device that notifies the relay device and receives the control information frame includes a frame analysis unit that analyzes the control information frame and notifies the load determination unit of a planned load of the line, and the load determination The unit may determine the line load from the line load.

  At this time, the opposite device may include a control information generation unit that generates control information to be transmitted to the network relay device, and may generate control information based on a transmission load.

  The network relay device further includes a frame transmission control unit that controls frame transmission to another network relay device, and the frame transmission control unit controls the bandwidth up to the planned line load obtained from the control information frame. You may make it do. The network relay device can perform data communication by designating a scheduled load on a line connected to the opposite device, but the opposite device processes the network relay device due to a temporary increase in network traffic. There is a case where network traffic exceeding the receiving load to be obtained is transmitted. At this time, it is possible to keep the reception load of the opposite device within a range that can be processed by performing bandwidth control with the scheduled load as an upper limit for the transmission load of the network relay device.

  In the network relay device, the frame transmission control unit may further perform delay control on the frame transmission side for a frame requiring delay control as priority control. When bandwidth control is performed with the scheduled load as the upper limit for the transmission load of the opposite device, it is considered that a delay more than conventional occurs in the frame transfer processing. In communications where arrival time delay is a problem, such as IP telephones, it is necessary to perform delay control on this data and transfer it with low delay. In addition, when frame discard occurs when bandwidth control is performed with the scheduled load as an upper limit for the transmission load of the opposite device, a priority frame is determined during reception processing of the network relay device. It is considered difficult to protect. For this reason, when it is found that frame discard occurs, discard control may be performed by discarding a frame with low priority during transmission processing as priority control in the opposite apparatus.

  In the network relay device, the load determination unit may further determine a line load from a link-up state of the line notified from the central control unit. In the network relay device, the link-up speed may be different for each line even when the link-up is performed for each line, when the link-up is not performed, and when the link-up is performed. For this reason, when the link-up line speed is low, the line load can be considered with the line speed as the upper limit.

  The network relay device further includes a load information transmission unit for exchanging load information between the plurality of network LSIs, and the load determination unit determines a load in a specific functional block by summing loads of a plurality of lines. You may make it do. In the transfer engine unit composed of a plurality of network LSIs, frame transfer processing is performed by a plurality of network LSIs. Therefore, a plurality of lines are bundled into one channel and transmitted to another network LSI. At this time, the load applied to the channel can be regarded as the total of the line loads. This channel exists in both the network LSI that transmits data and the network LSI that receives data.

  In the network relay device, the load determination unit may further determine a load in a specific functional block by summing loads of all lines by the load information transmission unit. Since the transfer engine unit configured by a plurality of network LSIs performs frame transfer processing by a plurality of network LSIs, the load applied to the switch fabric of the network relay device can be regarded as the sum of all line loads.

In the network relay device, the load determination unit further determines a function that is not used from an operation state of the network relay device in the central control unit and notifies the load determination unit of the function in the corresponding functional block. The load may be determined. In many cases, the network relay device employs additional functions such as a statistical function and a QoS control function in addition to data transfer. The network administrator selects and operates the necessary functions from these functions. It can be determined that the functional block that realizes the function not selected at this time has a small load.

  According to the present invention, it is possible to minimize frame discard and reduce power consumption in a network relay device that performs data transfer using a plurality of network LSIs.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows an example of a network relay device 100 having a transfer engine unit 101 composed of a plurality of network LSIs and a central control unit 102 that controls the operating state of the network relay device 100. The transfer engine unit 101 of FIG. 1 includes eight search LSIs 103, four transfer LSIs 104, and four switch LSIs 105. Each network LSI has a channel connecting the network LSIs, and performs data transfer through the channel.

  The search LSI 103 is connected to a plurality of external network lines (not shown in FIG. 1), determines the frame transfer destination port of the network relay device from the header information of the frame data, and transfers the frame data to the transfer LSI 104. The transfer LSI 104 transfers the frame data transferred from the search LSI 103 to the four switch LSIs 105 based on the load distribution method. The switch LSI 105 transfers the frame data to a transfer LSI 104 to which a search LSI 103 having a frame data frame transfer destination port is connected. The transfer LSI 104 transfers the frame data to the search LSI 103 having a frame transfer destination port for the frame data. The search LSI 103 transfers the frame data to the external network line connected to the frame data frame transfer destination port. The eight search LSIs 103 are connected to any of the four switch LSIs 105 via the four transfer LSIs 104. Accordingly, each of the eight search LSIs 103 that are bi-directionally connected to an external network line can be connected to an arbitrary switch LSI 105 via the transfer LSI 104 to which each is connected. Further, since the central control unit 102 in FIG. 1 is connected to the four switch LSIs 105, a frame transferred from an arbitrary search LSI 103 can reach the central control unit 102.

  Here, the search LSI 103, the transfer LSI 104, and the switch LSI 105 are also simply referred to as “network LSI”. In this embodiment, the transfer LSI 104 capable of transmitting and receiving is used, but the transfer LSI for reception (not shown) and the transfer LSI for transmission (not shown) are configured separately. May be. In the present embodiment, the search LSI 103 may also be configured separately according to functions in addition to transmission and reception. In the case of such a separate configuration, these may be configured by one LSI or may be configured by separate LSIs.

  In this embodiment, the frame transfer is performed with the configuration in which the transfer LSI 104 is arranged between the search LSI 103 and the switch LSI 105, but the frame transfer is performed with the configuration in which the search LSI 103 and the switch LSI 105 are directly connected. You may carry out.

FIG. 2 is a diagram in which the inside of the search LSI 103 is divided into functional blocks.
The search LSI 103 includes a downlink interface block 201 that is an interface with an external network line,
Ingress side downlink block 202 connected inside the downlink interface block 201,
The egress side downlink block 203 connected to the inside of the downlink interface block 201,
Ingress side line aggregation block 204 that aggregates ingress side downlink block 202;
An egress side line aggregation block 205 for aggregating the egress side downlink block 203;
A search memory interface block 206 that is an interface with a search table external memory not shown in FIG.
A search memory access block 207 connected inside the search memory interface block 206;
A buffer memory interface block 211 which is an interface with an external buffer memory not shown in FIG.
A buffer memory access block 212 connected to the inside of the buffer memory interface block 211;
Uplink interface block 216, which is an interface with transfer LSI 104,
An ingress uplink block 217 connected inside the uplink interface block 216,
Egress uplink block 218 connected inside uplink interface block 216;
Data processing block for transferring data between ingress side line aggregation block 204, egress side line aggregation block 205, search memory access block 207, buffer memory access block 212, ingress side uplink block 217, and egress side uplink block 218 219,
QoS control function block 220 for realizing the QoS control function,
Statistical function block 221 for realizing the statistical function,
Ingress side line load measurement block 222 that measures the ingress side line load in ingress side downlink block 202, and
A frame analysis block 223 for analyzing the ingress side frame in the ingress side downlink block 202;
Ingress load measurement block 224 that measures the line load for each frame transfer destination port on the ingress side in data processing block 219;
An egress side load measurement block 225 that measures the egress side line (channel) load within the data processing block 219;
A control information generation block 226 for generating control information from the load judgment result on the egress side in the data processing block 219;
A frame transmission control block 227 for performing priority control on the egress side in the data processing block 219;
A frequency voltage control block 228 for supplying a clock and an operating voltage to each functional block based on the load determination result;
Load information transmission block 229 for exchanging load information with other network LSIs,
A load determination control block 230 that determines the load of each functional block by determining the load of the line and the load of the functional block;
Consists of

  The search LSI 103 of this embodiment determines the frame transfer destination port of the network relay apparatus from the frame header information of the received frame and transfers the frame data, and the frame data extension information transferred from the transfer LSI 104. A function of transferring frame data in accordance with a frame transfer destination port; and a function of determining a control information frame exchanged between network relay apparatuses and transferring the frame to the central control unit 102.

  The search LSI 103 further includes a statistical function such as counting the amount of frame transfer.

  Further, the search LSI 103 searches the QoS condition table set by the device administrator using the combination of the packet header conditions as a search key, and determines the priority of the packet transfer processing within the device. A QoS control function for preferentially processing packets determined to have a high priority based on the priorities.

  Further, the search LSI 103 further divides the frame and the extended information into cell formats, “a function for converting the frame into a frame format in which extended information such as a frame transfer destination port is added and transmitting it to the transfer LSI 104”, and At least one of a function to transmit to the transfer LSI 104 and a function to restore the cell format data received from the transfer LSI 104 to a frame and transmit it to an external network line.

In the present embodiment, the search LSI 103 performs ingress processing of frame data as follows.
Frame data is received by the downlink interface block 201 and transferred to the ingress side downlink block 202. Further, the frame data of each line is transferred from the ingress side downlink block 202 to the ingress side line aggregation block 204.

  At this time, the ingress side line aggregation block 204 may aggregate the frame data of each line by time division control.

  The frame data of the ingress side line aggregation block 204 is transferred to the buffer external memory by the data processing block 219. In the transfer to the buffer external memory, the data is transferred from the data processing block 219 to the buffer external memory via the buffer memory access block 212 and the buffer memory interface block 211. Further, the data processing block 219 searches for the frame transfer destination port of the frame data. At this time, the search table external memory is accessed through the search memory access block 207 and the search memory interface block 206. The frame data for which the search processing has been completed is transferred from the buffer external memory to the data processing block 219 via the buffer memory interface block 211 and the buffer memory access block 212. In the data processing block 219, the frame data is transferred to the ingress side uplink block 217 with the frame data extension information including the searched frame transfer destination port information.

  At this time, the data processing block 219 may perform frame data transfer processing by arbitration control between the blocks.

  The frame data of the ingress side uplink block 217 is transferred to the transfer LSI 104 via the uplink interface block 216.

In the search LSI 103, frame data egress processing is as follows.
Frame data is received at the uplink interface block 216 and transferred to the egress side uplink block 218. The frame data of the egress side uplink block 218 is transferred to the buffer external memory by the data processing block 219. In the transfer to the buffer external memory, the data is transferred from the data processing block 219 to the buffer external memory via the buffer memory access block 212 and the buffer memory interface block 211. The frame data in the buffer external memory is transferred to the egress side line aggregation block 205 via the buffer memory interface block 211, the buffer memory access block 212, and the data processing block 219. The frame data of the egress side line aggregation block 205 is transferred to the egress side downlink block 203 connected to the frame transfer destination port according to the frame transfer destination port information included in the frame data extension information.

  At this time, the egress side line aggregation block 205 may aggregate the frame data of each line by time division control.

  The frame data of the egress side downlink block 203 is transferred to the external network line via the downlink interface block 201.

  In the present invention, the search LSI 103 further receives, as the frame analysis function of the frame analysis block 223, the control information frame that the opposite device stores and transmits the planned load of the transmission traffic via the downlink interface block 201. By analyzing the received control information frame, the scheduled load of the receiving side line is known and notified to the load determination control block 230 (1) “frame analysis function” is provided.

  Note that the frame analysis block 223 in the search LSI 103 is also simply referred to as a “frame analysis unit”.

The frame analysis function of the frame analysis block 223 in the search LSI 103 may be realized in the central control unit 102. The search LSI 103 further includes one or more of the following functions (2) to (8) as a load determination function of the load determination control block 230.
(2) “Receiving load determination function” for determining the line load from the line load measurement result of the reception process (ingress process) measured by the ingress side line load measurement block 222 as the ingress side process
(3) “Transmission load determination function” for determining the line load from the line load measurement result of the transmission process (egress process) measured by the egress side load measurement block 225 as the egress side process.
(4) “Line status determination function” that determines the maximum line load when it is determined as a standby line from the analysis result of control information frames exchanged between network relay devices
(5) “Scheduled load determination function” that knows the planned load of the line by notifying the planned load of the receiving line that the frame analysis block 223 has learned by analyzing the control information frame transmitted from the opposite device
(6) “Line load upper limit determination function” for determining the upper limit of the line load from the link up state of the line notified from the central control unit 102
(7) "Load prediction determination function" that predicts and determines load information by receiving the load information determined and measured by the load determination control block and each functional block of other network LSI via the load information transmission block 229 "
(8) “Function control load determination function” that determines the load of a function block from information on unnecessary functions notified from the central controller 102 according to the operation state of the network relay device
The load determination control block 230 determines a load determination result for each functional block from a combination of one or more load determination functions among the above (2) to (8). Based on the load determination result for each functional block determined here, the frequency power supply control block 228 supplies a clock and an operating voltage to each functional block.

  The search LSI 103 further generates, as the control information generation function of the control information generation block 226, (3) scheduled load information to be transmitted to the opposite device from the load determination result of the egress side line by the “transmission load determination function”. (9) “Control information generation function” is provided.

  The control information generation block 226 in the search LSI 103 is also simply referred to as “control information generation unit”.

  Further, the function of the control information generation block 226 in the search LSI 103 may be realized in the central control unit 102.

  The search LSI 103 further transmits as a frame transmission control function of the frame transmission control block 227 using a band according to the scheduled load information as a transmission band to the opposite device (10) “Band control function” (11) “Delay control function” reduces the latency by preferentially transmitting frames that must be transmitted with low latency, and discards low-priority frames when frame discard occurs during bandwidth control. Implement (12) At least one of “Discard control function” is provided.

  Note that the frame transmission control block 227 in the search LSI 103 is also simply referred to as a “frame transmission control unit”.

FIG. 3 is a diagram in which the inside of the transfer LSI 104 is divided into functional blocks.
The transfer LSI 104 includes a downlink interface block 301 that is an interface with the search LSI 103,
An ingress side downlink block 302 connected inside the downlink interface block 301;
The egress side downlink block 303 connected inside the downlink interface block 301;
An ingress side downlink aggregation block 304 for aggregating the ingress side downlink block 302;
Egress side downlink aggregation block 305 for aggregating egress side downlink block 303;
Uplink interface block 306, which is an interface with switch LSI 105,
An ingress uplink block 307 connected inside the uplink interface block 306,
Egress uplink block 308 connected inside uplink interface block 306;
Ingress side uplink aggregation block 309 that aggregates ingress side uplink block 307,
Egress-side uplink aggregation block 310 that aggregates egress-side uplink block 308;
A data processing block 311 for transferring data between the ingress side downlink aggregation block 304, the egress side downlink aggregation block 305, the ingress side uplink aggregation block 309, and the egress side uplink aggregation block 310;
Statistical function block 312 for realizing the statistical function,
An ingress load measurement block 313 for measuring the ingress line (channel) load in the ingress downlink block 302;
An egress side load measurement block 314 for measuring the egress side line (channel) load in the egress side uplink block 308;
A frequency voltage control block 315 that supplies a clock and an operating voltage to each functional block based on the load determination result;
A load information transmission block 316 for exchanging load information with other network LSIs;
A load determination control block 317 that determines the load of each functional block by determining the load of the line (channel) and the load of the functional block;
Consists of

  The transfer LSI 104 has a function of transferring the frame data received from the search LSI 103 to the switch LSI 105 and a function of transferring the frame data received from the switch LSI 105 to the corresponding search LSI 103 based on the extended information including the transfer destination port information. And comprising.

  Further, when the data format between the search LSI 103 and the transfer LSI 104 is a frame format, the transfer LSI 104 divides the extended information such as the frame and the frame transfer destination port into the cell format and transfers it to the switch LSI 105 to switch A function that restores cell format data received from LSI 105 to a frame and transmits it to an external network line ”and“ A frame slice and extended information are divided into bit slice formats divided into multiple bits and transferred to switch LSI 105. The bit slice format data received from the switch LSI 105 may be restored to a frame and transmitted to an external network line.

  The transfer LSI 104 further has a statistical function such as counting the amount of transfer of frame data.

In the present embodiment, ingress processing of frame data in the transfer LSI 104 is as follows.
Frame data is received at the downlink interface block 301 and transferred to the ingress side downlink block 302. Further, the frame data of each channel is transferred from the ingress side downlink block 302 to the ingress side downlink aggregation block 304.

  At this time, the ingress side downlink aggregation block 304 may aggregate the frame data of each channel by time division control.

  The frame data of the ingress side downlink aggregation block 304 is transferred to the ingress side uplink aggregation block 309 by the data processing block 311.

  At this time, the data processing block 311 may perform frame data transfer processing by arbitration control between the blocks.

  The frame data of the ingress side uplink aggregation block 309 is transferred to the ingress side uplink block 307 to which the switch LSI 105 designated based on the load distribution method is connected.

  At this time, the ingress side uplink aggregation block 309 may aggregate the frame data of each channel by time division control.

  The frame data of the ingress side uplink block 307 is transferred to the switch LSI 105 via the uplink interface block 306.

In the transfer LSI 104, frame data egress processing is as follows.
The uplink interface block 306 receives the frame data and transfers it to the egress side uplink block 308. Further, the frame data of each channel is transferred from the egress side uplink block 308 to the egress side uplink aggregation block 310.

  At this time, the egress side uplink aggregation block 310 may aggregate the frame data of each channel by time division control.

  The frame data of the egress side uplink aggregation block 310 is transferred to the egress side downlink aggregation block 305 by the data processing block 311. The frame data of the egress side downlink aggregation block 305 is transferred to the egress side downlink block 303 to which the search LSI 103 having the frame transfer destination port is connected according to the frame transfer destination port information included in the frame data extension information.

  At this time, the egress side downlink aggregation block 303 may aggregate the frame data of each channel by time division control. The frame data of the egress side downlink block 303 is transferred to the search LSI 103 via the downlink interface block 301.

In the present invention, the transfer LSI 104 further includes one or more of the following functions (13) to (16) as a load determination function of the load determination control block 317.
(13) “Reception load determination function” for determining the channel load from the channel load measurement result of the reception process (ingress process) measured by the ingress load measurement block 313 as the ingress process
(14) “Transmission load determination function” for determining the channel load from the channel load measurement result of the transmission processing (egress processing) measured by the egress side load measurement block 314 as the egress side processing.
(15) “Load prediction determination function” which predicts and determines load information by receiving the load information determined and measured by the load determination control block and each functional block of another network LSI via the load information transmission block 316 "
(16) “Function control load determination function” for determining the load of a function block from information on unnecessary functions notified from the central control device 102 according to the operation state of the network relay device
The load determination control block 317 determines a load determination result for each functional block from a combination of one or more load determination functions among the above (13) to (16). Based on the load determination result for each functional block determined here, the frequency voltage control block 315 supplies a clock and an operating voltage to each functional block.

FIG. 4 is a diagram in which the inside of the switch LSI 105 is divided into functional blocks.
Switch LSI 105
Ingress side interface block 401 which is an ingress side interface with the transfer LSI 104,
An ingress side data channel block 402 connected inside the ingress side interface block 401;
Egress side interface block 403 which is an egress side interface with the transfer LSI 104,
Egress side data channel block 404 connected inside egress side interface block 403,
A receiving side control interface block 405 which is a receiving side interface to the central control unit 102;
A receiving control channel block 406 connected inside the receiving control interface block 405;
A transmission side control interface block 407 which is a transmission side interface to the central control unit 102;
A transmitter control channel block 408 connected inside the transmitter control interface block 407;
Ingress side channel aggregation block 409 that aggregates ingress side channel block 402 and reception side control channel block 406, and
An egress side channel aggregation block 410 that aggregates the egress side channel block 404 and the transmission side control channel block 408;
A data processing block 411 for transferring data between the ingress side channel aggregation block 409 and the egress side channel aggregation block 410;
Statistical function block 412 for realizing the statistical function,
A data load measurement block 413 for measuring the line (channel) load of the ingress side channel in the ingress side channel block 402;
A control load measurement block 414 for measuring the line (channel) load of the reception side control channel in the reception side control channel block 406;
A frequency voltage control block 415 that supplies a clock and an operating voltage to each functional block based on the load determination result;
A load information transmission block 416 for exchanging load information with other network LSIs;
A load determination control block 417 that determines the load of each functional block by determining the load of the line (channel) and the load of the functional block;
Consists of

  Note that one or more combinations of the frequency voltage control block 228 in the search LSI 103, the frequency voltage control block 315 in the transfer LSI 104, and the frequency voltage control block 415 in the switch LSI 105 are simply “frequency voltage control”. It is also called “part”.

  Note that one or more combinations of the load information transmission block 229 in the search LSI 103, the load information transmission block 316 in the transfer LSI 104, and the load information transmission block 416 in the switch LSI 105 are simply referred to as “load information transmission block”. It is also called “part”.

  The switch LSI 105 has a function of transferring the frame data received from the transfer LSI 104 to the corresponding transfer LSI 104 based on the extended information.

  The switch LSI 105 further includes a statistical function such as counting the amount of frame data transferred.

In the present embodiment, frame data transfer processing in the switch LSI 105 is as follows.
The ingress side interface block 401 receives the frame data and transfers it to the ingress side data channel block 402. Further, the frame data of each channel is transferred from the ingress side data channel block 402 to the ingress side channel aggregation block 409.

  At this time, the ingress side channel aggregation block 409 may aggregate the frame data of each channel by time division control.

  The frame data of the ingress side channel aggregation block 409 is transferred to the egress side channel aggregation block 410 by the data processing block 411.

  At this time, the data processing block 411 may perform frame data transfer processing by arbitration control between the blocks.

  The frame data of the egress side channel aggregation block 410 is transferred to the egress side data channel block 404 to which the transfer LSI 104 that can transfer to the frame transfer destination port is connected according to the frame transfer destination port information included in the frame data extension information. . At this time, when the frame data is a control information frame, the frame data is transferred to the transmission side control channel block 408 to which the central control unit 102 is connected.

  At this time, the egress side channel aggregation block 410 may aggregate the frame data of each channel by time division control.

  The frame data of the egress side channel block 404 is transferred to the transfer LSI 104 via the egress side interface block 403. At this time, when the frame data is a control information frame, the frame data of the transmission side control channel block 408 is transferred to the central control unit 102 via the transmission side control interface block 407.

  In the switch LSI 105, the frame data transfer process of the control information frame generated by the central control unit 102 is as follows. The receiving side control interface block 405 receives the frame data and transfers it to the receiving side control channel block 406. Further, the frame data of the receiving side control channel block 406 is transferred to the ingress side channel aggregation block 409. The frame data of the ingress side channel aggregation block 409 is transferred to the egress side channel aggregation block 410 by the data processing block 411. The frame data of the egress side channel aggregation block 410 is transferred to the egress side data channel block 404 to which the transfer LSI 104 that can transfer to the frame transfer destination port is connected according to the frame transfer destination port information included in the frame data extension information. . The frame data of the egress side channel block 404 is transferred to the transfer LSI 104 via the egress side interface block 403.

In the present invention, the switch LSI 105 further includes one or more of the following (17) to (19) as a load determination function of the load determination control block 417.
(17) “Reception load determination function” for determining the channel load from the channel load measurement result of the reception processing (ingress processing) measured by the data load measurement block 413 as ingress processing
(18) “Load prediction determination function” that predicts and determines load information by notifying the load information transmission block 416 of the load information determined and measured by the load determination control block and each functional block of another network LSI. "
(19) “Function control load determination function” for determining the load of a function block from information on unnecessary functions notified from the central control device 102 according to the operation state of the network relay device
The load determination control block 417 determines a load determination result for each functional block from a combination of one or more load determination functions among the above (17) to (19). Based on the load determination result for each functional block determined here, the frequency voltage control block 415 supplies a clock and an operating voltage to each functional block.

The central control unit 102 includes the following (20) as a load determination function.
(20) Upon receiving notification of planned load information indicating the planned load of each line included in the network relay apparatus 100 from the management server inside or outside the network relay apparatus 100, the planned load of each line and the load of each functional block "Scheduled load adjustment function"
One or more combinations of the load determination control block 230 in the search LSI 103, the load determination control block 317 in the transfer LSI 104, the load determination control block 417 in the switch LSI 105, and the central control unit 102 Is also simply referred to as a “load determination unit”.

  In the present invention, the power consumption is reduced by switching at least one of the clock and the operating voltage supplied from the frequency voltage control unit to each functional block of the network LSI based on the load determination result of the load determination unit.

In the present invention, the load determination method of the load determination unit is an important factor in realizing power consumption reduction. Hereinafter, the load determination method of the load determination unit will be described.
A. Load judgment method based on load measurement:
B. Load judgment method based on line operation state judgment:
C. Load judgment method based on planned load exchange between network relay devices:
D. Load judgment method based on line link up state judgment:
E. Load judgment method based on load information exchange between network LSIs:
F. Load judgment method based on judgment of specific function operating state:
G. Load judgment method based on the management server's scheduled load information notification:
A. Load judgment method based on load measurement:
This load determination method determines the load based on the actual load on the channel (or line), and determines the load on the corresponding functional block based on the load determination result. In this embodiment, as the load determination function, (2) “reception load determination function”, (3) “transmission load determination function” of the search LSI 103, and (13) “reception load determination function” of the transfer LSI 104 (14) One or more combinations of “transmission load determination function” and (17) “reception load determination function” of the switch LSI 105. Table 1 to be described later classifies each functional block in the network LSI according to the load determination method. For example, in the case of the search LSI 103 of No. 1, the ingress side downlink depends on the ingress side load of the channel (line). It has been shown that the load of block 202 can be determined. Therefore, for example, in order to determine the load of the ingress side downlink block 202a in FIG. 2, (2) “reception load determination function” of the search LSI 103 is used as the load determination function, and the measurement result of the ingress side line load measurement block 222a. What is necessary is just to determine load.

  For example, in the case of the search LSI 103 of item number 3 in Table 1, it is shown that the load of the search memory access block 207 can be determined by the total load of all channels in the LSI. The load of the search memory access block 207 may be determined by using both (2) “reception load determination function” and (3) “transmission load determination function” of the LSI 103.

  Based on the determined load determination result of each functional block, power consumption can be reduced by switching at least one of a clock and an operating voltage supplied to each functional block by the frequency voltage control unit.

  In this load determination method, the generation of frame discard may be suppressed by using flow control defined by IEEE 802.3x.

B. Load judgment method based on line operation state judgment:
This load determination method determines the load based on the operation state of the line, and determines the load on the corresponding functional block based on the load determination result. In this embodiment, the load determination function indicates (4) “line state determination function” of the search LSI 103. (4) The “line state determination function” is an analysis of control information frames exchanged between network relay devices by the central control unit 102, so that the Ring protocol, the STP, the VRRP, the GSRP, the VSRP, The line state is determined according to the protocol such as FVRP, and the line load determined as the standby line is determined.

Further, in the VRRP, GSRP, VSRP, and FVRP protocols, the entire device may be used as a standby device.
The line status determination may be performed every time a frame is received. FIG. 5 shows a routine of line state determination processing (step S50) for each frame reception. Here, the operation in STP will be described as an example.

  In step S500, frame reception on the line is recognized, and the process proceeds to step S510. In step S510, it is determined whether the received frame is a control information frame. The control information frame is determined by analyzing the frame header in the search LSI 103, for example. If a frame other than the control information frame is received, the process proceeds to step S511. In step S511, the line state is maintained. STP does nothing as processing.

  If the received frame is a control information frame in step S510, the process proceeds to step S520. In step S520, the received control information frame is transferred to central control unit 102, and the process proceeds to step S530. In step S530, the received control information frame is analyzed to determine whether or not the line is a standby line. The analysis of the control information frame is performed by the central control unit 102 in accordance with the protocol processing. If it is determined that the line is a standby line, the process proceeds to step S540. In STP, when a line is determined to be in a blocking state, this line is determined to be a standby line. In step S540, the line is processed as a standby line. If the line is a standby line, the load determination control block 230 of the search LSI 103 having the line is notified.

  If it is determined in step S530 that the line is not a standby line, the process proceeds to step S531. In step S531, the received control information frame is analyzed to determine whether the line is an active line. The analysis of the control information frame is performed by the central control unit 102 in accordance with the protocol processing. If it is determined that the line is an active line, the process proceeds to step S541. In STP, when a line is determined as one of a listening state, a learning state, and a forwarding state, this line is determined to be an active line. In step S541, the line is processed as an active line. If the line is an active line, the load determination control block 230 of the search LSI 103 having the line is notified.

  If the line is not determined to be an active line, the process proceeds to step S532. In step S532, the line state is maintained. STP does nothing as processing. For example, in the case of the search LSI 103 of item No. 1 in Table 1, since it is shown that the load of the ingress side downlink block 202 can be determined by the ingress side load of the channel (line), for example, the ingress side downlink in FIG. To determine the load of the block 202a, the search LSI 103 (4) “line state determination function” is used as the load determination function, and the line connected to the downlink interface block 201a is determined to be a standby line. In this case, it is considered that the load on the line is such that the control information frame is transmitted and received, and thus the load on the ingress side downlink block 202a can be determined.

  Based on the determined load determination result of each functional block, power consumption can be reduced by switching at least one of a clock and an operating voltage supplied to each functional block by the frequency voltage control unit.

C. Load judgment method based on planned load exchange between network relay devices:
In this load determination method, the load is determined by exchanging the scheduled transmission load for each line between the network relay devices, and the load is determined for the corresponding functional block based on the load determination result. In this embodiment, the load determination function indicates (5) “scheduled load determination function” of the search LSI 103.

  Further, this load determination method may function by combining (1) “frame analysis function” of the search LSI 103 and (9) “control information generation function” of the search LSI 103.

  This load determination method in the case of not combining (1) “frame analysis function” and (9) “control information generation function” of the search LSI 103 transfers the control information frame received on the line to the central control unit 102, Based on the analysis result of the central control unit 102, the scheduled load of the reception line that receives transmission from other network devices is determined, and from the transmission load determination result determined by (3) “transmission load determination function” for each line. The central control unit 102 generates and transfers a control information frame indicating a planned transmission load for another network relay device.

  When functioning in combination with (1) “frame analysis function” of the search LSI 103, the control information frame received via the line is not passed through the central control unit 102 by the (1) “frame analysis function” of the search LSI 103. Then, the frame analysis block 223 of the search LSI 103 is analyzed, and the scheduled load of the reception line receiving the transmission from another network device is determined.

  When functioning in combination with (9) “control information generation function” of the search LSI 103, the transmission load determination result of each line in the search LSI 103 ((3 ) Based on the “transmission load determination function” or the like), a control information frame indicating a transmission load scheduled for another network relay device is generated and transferred without going through the central control unit 102.

  In combination with these functions, this load determination method can perform control information frame analysis processing and control information frame generation processing without using the central control unit 102 in exchanging scheduled loads.

  Further, this load determination method may be combined with the frame transmission control function of the search LSI 103. The search LSI 103 has a frame transmission control function (10) for transmitting a band according to a planned load as a transmission band to the opposite device (10) and for a frame that must be transmitted with low latency during the bandwidth control ( 11) At least one of a delay control function and a discard control function that discards a low-priority frame when a frame discard occurs during bandwidth control is provided.

  In the following, it is assumed that this load determination method is made to function by combining (1) “frame analysis function” of the search LSI 103 and (9) “control information generation function” of the search LSI 103.

  However, in the following description, the processing performed by the search LSI 103 (1) “frame analysis function” and the search LSI 103 (9) control information generation function may be performed by the central control unit 102.

  The (10) “bandwidth control function” can perform bandwidth control processing on network traffic transmitted from the network relay device to the opposite device.

  FIG. 6 shows an example of a graph that displays changes in network traffic in time series when there is no bandwidth control processing. The graph of FIG. 6 represents, in a time series, fluctuations in network traffic, link up speed, and planned load when there is no bandwidth control processing. In the graph of FIG. 6, the link-up speed is 10 Gbps and the planned load is 4 Gbps.

  However, in FIG. 6, burst transfer of network traffic occurs instantaneously and exceeds the planned load at time t1. In this case, since the opposite device lowers the line processing performance in accordance with the scheduled load notified by the control information frame, it is considered that the frame is discarded when the burst transfer of the network traffic occurs.

  FIG. 7 shows an example of a graph that displays changes in network traffic in time series when there is a bandwidth control process. The graph of FIG. 7 represents the fluctuation of the network traffic, the link-up speed, and the scheduled load in time series when there is bandwidth control. In the graph of FIG. 7, the link-up speed is 10 Gbps and the planned load is 4 Gbps.

  In the case of the graph of FIG. 7, the network relay device performs the bandwidth control process with the planned load as the upper limit for the network traffic transmitted to the opposite device, so that no frame discard occurs in the opposite device. Conceivable.

  Further, there may be a case where the frame is discarded even if the bandwidth control is performed with the planned load as the upper limit. FIG. 8 shows an example of a graph that displays changes in network traffic in a time series when there is no bandwidth control processing, as in FIG. 6. The graph of FIG. 8 represents network traffic fluctuations and link-up speeds when there is no bandwidth control in time series. In the graph of FIG. 8, the link-up speed is 10 Gbps.

  In the graph of FIG. 8, a burst transfer of network traffic occurs as in the graph of FIG.

  For example, in the graph of FIG. 8, when the scheduled load of the line is 4 Gbps, it is considered that the frame is discarded in the opposite device if there is no bandwidth control.

  On the other hand, in FIG. 8, as in FIG. 7, even when the bandwidth control processing is performed on the network traffic transmitted to the opposite device with the planned load of 4 Gbps as the upper limit, the network traffic load is too large for the planned load. It is considered that the frame is discarded in the network relay device.

  Therefore, in this load determination method, the scheduled load fluctuation determination process for determining the fluctuation of the line transmission planned load is performed by (9) “control information generation function” of the search LSI 103, and the planned load is changed according to the network traffic. In this way, discarding of the frame may be suppressed.

  FIG. 9 shows a planned load fluctuation determination process when the planned load is changed to 4 Gbps, 6 Gbps, 8 Gbps, and 10 Gbps, and the planned load fluctuation threshold that fluctuates the planned load compared to the line load is equal to the planned load. Step S90) shows an example of a routine.

  In step S900, the load determination control block 230 of the search LSI 103 determines the transmission load of the line by (3) “transmission load determination function” or the like, and the process proceeds to step S910. In step S910, (9) “control information generation function” of the search LSI 103 determines whether or not the transmission load determination result of the line is less than 8 Gbps. If the transmission load judgment result of the line is 8 Gbps or more, the process proceeds to step S911. In step S911, the opposite load is notified to the scheduled load of the line as 10 Gbps.

  If the line transmission load determination result is less than 8 Gbps in step S910, the process proceeds to step S920. In step S920, it is determined whether the planned load of the line is less than 8 Gbps. If the planned load on the line is 8 Gbps or more, the process proceeds to step S921. In step S921, it is determined whether or not the line transmission load determination result is less than 8 Gbps continuously for a certain period of time. If the line transmission load judgment result does not become less than 8 Gbps continuously for a certain period of time, the process proceeds to step S922. In step S922, the planned load on the line is maintained.

  In step S921, when the line transmission load determination result is less than 8 Gbps continuously for a predetermined time, the process proceeds to step S931. In step S931, the opposite load is notified to the scheduled load of the line as 8 Gbps.

  In step S920, if the planned load of the line is less than 8 Gbps, the process proceeds to step S930. In step S930, it is determined whether or not the line transmission load determination result is less than 6 Gbps. If the transmission load judgment result of the line is 6 Gbps or more, the process proceeds to step S931. In step S931, the opposite load is notified to the scheduled load of the line as 8 Gbps.

  In step S930, if the line transmission load determination result is less than 6 Gbps, the process proceeds to step S940. In step S940, it is determined whether the planned load of the line is less than 6 Gbps. If the planned load on the line is 6 Gbps or more, the process proceeds to step S941. In step S941, it is determined whether or not the line transmission load determination result is less than 6 Gbps for a certain period of time. If the line transmission load judgment result does not become less than 6 Gbps continuously for a certain period of time, the process proceeds to step S942. In step S942, the planned load on the line is maintained.

  In step S941, when the line transmission load determination result is less than 6 Gbps for a certain period of time, the process proceeds to step S951. In step S951, the opposite line device is notified of the planned load of the line as 6 Gbps.

  In step S940, if the planned load on the line is less than 4 Gbps, the process proceeds to step S950. In step S950, it is determined whether or not the line transmission load determination result is less than 4 Gbps. If the line transmission load determination result is 4 Gbps or more, the process proceeds to step S951. In step S951, the opposite line device is notified of the planned load of the line as 6 Gbps.

  In step S950, when the line transmission load determination result is less than 4 Gbps, the process proceeds to step S960. In step S960, the scheduled load of the line is notified to the opposite device as 4 Gbps.

  Here, since the graph of FIG. 8 is a fluctuation of network traffic when there is no bandwidth control processing, it is considered as a line transmission load determination result.

  The graph of FIG. 10 shows an example of the graph after performing the bandwidth control process based on the scheduled load fluctuation determination process for the network traffic of FIG. The graph of FIG. 10 represents, in a time series, fluctuations in network traffic, fluctuations in planned load, fluctuations in processing capacity, and link-up speed when there is a bandwidth control process based on the scheduled load fluctuation determination process. .

  The following will be described with reference to FIGS. Note that the times t1, t2, t3, t4, t5, t6, t7, and t8 in FIGS. 8 and 10 indicate the same time.

  In FIG. 8, since the line transmission load determination result is 4 Gbps or more and less than 6 Gbps at time t1, and the line load is 4 Gbps, the line load is notified to the opposite apparatus at 6 Gbps. At t2, the planned load in FIG. 10 is changed to 6 Gbps. However, since the processing capacity fluctuates in conjunction with the notification of the planned load, when increasing the planned load, a control information frame is transmitted to notify the opposite device of the fluctuation of the planned load, and the processing capacity increases. Wait until time (t2-t1) and increase the planned load. By increasing the planned load of the network relay device to 6 Gbps, bandwidth control processing is performed so that the upper limit of network traffic from the network relay device to the opposite device is 6 Gbps.

  Further, in this load determination method, after the control information frame is transmitted, the planned load of the network relay device is increased after waiting for reception of a response frame such as a control information frame for notifying an increase in processing capacity from the opposite device. Also good.

  In FIG. 8, because the line transmission load determination result is 8 Gbps or more at time t2, the scheduled load of the line is notified to the opposite apparatus at 10 Gbps, and then the network relay apparatus at time t3 in FIG. The planned load is increased stepwise such that the planned load is changed to 8 Gbps and the planned load in FIG. 10 is changed to 10 Gbps at time t4.

  However, if the line transmission load determination result in FIG. 8 is 6 Gbps or more and less than 8 Gbps at time t4, the planned load is maintained.

  Accordingly, in the graph of FIG. 10, it is considered that neither the network relay device nor the opposite device discards the frame.

  Here, a certain time in FIG. 9 is Δt, and in the following description, the difference between time t6 and time t5, the difference between time t7 and time t6, and the difference between time t8 and time t7 are Δt or more. Shall.

  In FIG. 8, since the line transmission load determination result is continuously less than 8 Gbps from time t5 to time t6 and the planned load of the line is 10 Gbps, the planned load is changed to 8 Gbps at time t6. In FIG. 8, since the line transmission load determination result is continuously less than 6 Gbps from time t6 to time t7 and the planned load of the line is 8 Gbps, the planned load is changed to 6 Gbps at time t7. In FIG. 8, since the line transmission load determination result is continuously less than 8 Gbps from time t7 to time t8 and the planned load of the line is 6 Gbps, the planned load is changed to 4 Gbps at time t8.

  However, when the planned load is reduced, a control information frame is transmitted to notify the opposite apparatus of the variation in the planned load. At this time, since it is not necessary to wait for the opposing device to reduce the processing capacity, the planned load may be reduced simultaneously with the notification of the fluctuation of the planned load.

  In the graph of FIG. 10, it is assumed that the processing performance is always greater than or equal to the planned load.

  In the flowchart of FIG. 9, four types of planned loads of 4 Gbps, 6 Gbps, 8 Gbps, and 10 Gbps are considered. However, any number of scheduled loads may be designated.

  Further, in the flowchart of FIG. 9, the planned load fluctuation threshold is set to the same value as the planned load, but the planned load fluctuation threshold may take a value different from the planned load.

  Further, in the flowchart of FIG. 9, the planned load fluctuation threshold value has the same value for the increase threshold value and the decrease threshold value, but may take different values.

  Further, in FIG. 10, the change in the processing performance is performed in proportion to the time, but this is different depending on the processing performance control method.

  In the operation of the LSI, when the operating voltage changes abruptly, the operation of the LSI becomes unstable, and in the worst case, the LSI may be broken. This is because a sudden change in the operating voltage occurs even when the clock is suddenly changed. For this reason, the clock and the operating voltage cannot be switched rapidly.

  For this reason, the planned load of the line is set to a small value for the processing performance of the line, and when the planned load of the line is increased, the planned load of the line is increased step by step while improving the processing performance. And Thereby, in this load determination method, it is possible to suppress a rapid change in the clock and the operating voltage.

  The (11) “delay control function” can perform a delay control process for transmission without causing a delay in arrival time in communications where the delay in arrival time is a problem due to bandwidth control, such as an IP phone.

  The (12) “discard control function” uses a low-priority frame in order to protect a high-priority frame when a burst transfer of network traffic occurs in a network relay device that does not have the (10) “bandwidth control function”. Disposal and disposal control processing can be performed.

  The (12) “discard control function” may be provided in a network relay device provided with the (10) “bandwidth control function”. This is because, even in a network relay device having the (10) “bandwidth control function”, if a very special network traffic burst transfer such as a DDoS (Distributed Denial of Service) attack occurs, the frame may be discarded. Because there is.

  With the load determination method described above, it is possible to determine the load on the receiving line from the scheduled load that is notified by the opposite apparatus. For example, in the case of the search LSI 103 of No. 1 in Table 1, since it is shown that the load of the ingress side downlink block 202 can be determined by the ingress side load of the line, the ingress side downlink in FIG. In order to determine the load of the block 202a, (5) “scheduled load determination function” of the search LSI 103 is used as a load determination function to determine the planned load applied to the line connected to the downlink interface block 201a. The load on the ingress side downlink block 202a can be determined based on the scheduled load.

  Based on the determined load determination result of each functional block, power consumption can be reduced by switching at least one of a clock and an operating voltage supplied to each functional block by the frequency voltage control unit.

D. Load judgment method based on line link up state judgment:
This load determination method determines the line load from the link-up state for each line between network relay devices, and determines the load in the corresponding functional block based on the load determination result. In the present embodiment, as the load determination function, (6) “line load upper limit determination function” of the search LSI 103 is indicated.

  The link-up state includes link-up and link-down, and link-up further includes a link-up state for each line speed. In other words, when the link speed is switched to 10 Mbps, 100 Mbps, or 1000 Mbps as in 1000BASE-T defined by IEEE 802.3ab, each line speed becomes the upper limit of the line load.

  (6) The “line load upper limit determination function” determines the upper limit of the line load from the link up state of the line notified from the central control unit 102. In the link up state notified, each line is linked up. In addition to information on whether or not the link is up, the line speed when the link is up is also notified. Therefore, (6) “line load upper limit determination function” can determine the line load according to the line speed of the line that is linked up among the plurality of lines. Thus, for example, in the case of the search LSI 103 of item No. 1 in Table 1, it is shown that the load of the ingress side downlink block 202 can be determined by the ingress side load of the channel (line). In order to determine the load of the side downlink block 202a, the search LSI 103 (6) “line load upper limit determination function” is used as the load determination function, and the link up state of the line connected to the downlink interface block 201a is determined. The line load according to the line speed can be determined, and the load on the ingress side downlink block 202 can be determined based on the determination result.

  Further, for example, in the case of the search LSI 103 of item number 3 in Table 1, it is shown that the load of the search memory access block 207 can be determined by the total load of all channels (lines) in the LSI. In order to determine the load of the search memory access block 207, the (6) “line load upper limit determination function” of the search LSI 103 is used as the load determination function, and a plurality of connections connected to the downlink interface blocks 201a to 201d are used. It is possible to determine the total value of the line load according to the line speed of the line that is linked up among the lines, and to determine the load of the search memory access block 207 based on the determination result.

  Based on the determined load determination result of each functional block, power consumption can be reduced by switching at least one of a clock and an operating voltage supplied to each functional block by the frequency voltage control unit.

E. Load judgment method based on load information exchange between network LSIs:
This load determination method determines the load on the corresponding network LSI based on the load information of the preceding network LSI by exchanging the load information between the network LSIs. In this embodiment, (18) “load prediction determination function” of the switch LSI 105, (15) “load prediction determination function” of the transfer LSI 104, and (7) “load prediction” of the search LSI 103 are used as the load determination function. One or more combinations of “determination function”.

  Note that focusing on the load on the ingress side downlink block 302 of the transfer LSI 104 of No. 1 in Table 1 shows that the determination is made based on the ingress side load of the channel. (15) By using the “load prediction determination function” and notifying the load of all lines measured by the ingress side line load measurement blocks 222a to 222d of the search LSI 103, the search LSI 103 is connected from the total. The load on the ingress side downlink block 302 of the transfer LSI 104 can be determined. It is also possible to determine the total load of the four switch LSIs 105 from the total load of the ingress downlink block 302 of all the transfer LSIs 104a to 104d.

  Further, in all search LSIs 103, the ingress load measurement block 224 of the search LSI 103 measures the line load for each frame transfer destination port, and the load for each frame transfer destination port in all the search LSIs 103 in the network relay device. The total of the measurement results is notified by (7) “load prediction determination function” of each search LSI 103 and (15) “load prediction determination function” of each transfer LSI 104, so that the egress side of each search LSI 103 Downlink block 203 (search LSI column 103 of item number 2 in Table 1), egress side uplink block 218 for each search LSI 103 (search LSI column 103 of item number 5 in Table 1), egress of each transfer LSI 104 The load on the side downlink block 303 (item 2 transfer LSI 104 column in Table 1) can be determined.

  Based on the determined load determination result of each functional block, power consumption can be reduced by switching at least one of a clock and an operating voltage supplied to each functional block by the frequency voltage control unit.

F. Load judgment method based on judgment of specific function operating state:
In this load determination method, the central controller 102 determines a function that is not used from the functions in the network LSI according to the operation state of the network relay device, and determines the load of the corresponding function block. In this embodiment, (19) “Function control load determination function” of the switch LSI 105, (16) “Function control load determination function” of the transfer LSI 104, and (8) “ One or more combinations of “function control load determination function”.

  That is, the central control unit 102 determines a function that is not used among the statistical function, QoS control function, and various power consumption reduction functions, and determines the load of each functional block. These are exemplified in item number 11 of Table 1.

  Based on the determined load determination result of each functional block, power consumption can be reduced by switching at least one of a clock and an operating voltage supplied to each functional block by the frequency voltage control unit.

G. Load judgment method based on the management server's scheduled load information notification:
In this load determination method, the central control unit 102 receives notification of planned load information indicating the planned load for one or more lines included in the network relay device from a management server inside or outside the network relay device. Based on the load information, the scheduled load of each line and the load of each functional block are determined. In this embodiment, (7) “load prediction determination function” of the search LSI 103, (1) “frame analysis” of the search LSI 103, and (15) “load prediction determination function” of the transfer LSI 104 are used as load determination functions. ”, (18)“ Load prediction determination function ”of the switch LSI 105, and (20)“ Scheduled load adjustment function ”of the central control unit 102. In addition, it is desirable to transfer the scheduled load information in this load determination method in the form of a packet so that it can be notified to a network relay device that is physically far away via another network relay device.

  FIG. 11 is a diagram showing a sub-network composed of network relay devices A to H and management servers A and B. The network relay devices A to H are also connected to other network relay devices and servers (not shown). In this embodiment, the planned load information is notified from the management server A to the network relay devices A to E, and the planned load information is notified from the management server B in the network relay device E to the network relay devices F to H. The The scheduled load information includes the scheduled transmission load and the scheduled reception load, but only one of them may be notified. In addition, with regard to the scheduled load, only the scheduled load is notified, and the planned load is exchanged between network relay devices in the same way as "C. Load determination method based on the exchange of planned loads between network relay devices". You may determine by doing.

  When receiving the control information packet storing the scheduled load information of each line from the management servers A and B, the network relay device A-H transfers the control information packet to the central control unit 102. The central control unit 102 analyzes the control information packet, extracts the planned load information, and determines the planned load of each line. Further, the load of each functional block in each network LSI is determined based on the planned load of each line, the load information transmission block 229 of the search LSI 103, the load information transmission block 316 of the transfer LSI 104, and the load of the switch LSI 105 One or more of the information transmission blocks 416 are notified.

  As an example of the determination of the functional block load, for example, in the case of the search LSI 103 of item number 1 in Table 1, the load of the ingress side downlink block 202 can be determined by the ingress side load of the channel (line). The load on the ingress side downlink block 202 can be determined based on the scheduled reception load extracted from the load information.

  The central control unit 102 may transmit the scheduled load for each line to each network LSI, and the load for each functional block may be determined by the load determination control block in each network LSI. In addition, the frame analysis block 223 of the search LSI 103 analyzes the control information packet transmitted from the management server, extracts the planned load information, and notifies other network LSIs, thereby partially processing the central control unit 102. It is also possible to substitute the whole thing.

  In this embodiment, the management servers A and B determine the optimum performance that the network relay device should operate (for example, the reception line load and the transmission line load that should be guaranteed to operate), and as the scheduled load information indicating the planned load of each line Notify each network relay device A-H. The optimum performance judgment method includes a judgment method based on the load measurement result inside the network relay device, a judgment method based on prediction based on statistical data and frequency analysis, and a decrease or increase in traffic that is known in network management. Judgment method to determine the optimum performance by setting the time zone to be performed, or the schedule of events that can be predicted in advance among events that may cause fluctuations in network traffic such as the soccer World Cup and the Olympics is described in the event calendar One or more determination methods based on contents set as a schedule in the management server are provided. The management server only has to notify the scheduled load information to each network relay device based on the determined optimum performance, and the method for determining the optimum performance of the management server is not particularly limited. Among events that occur unexpectedly, such as disasters, incidents, and accidents, and that may cause fluctuations in network traffic, for events that cannot be predicted in advance, the planned load on each network relay device is determined by the management server program or administrator operations. Information may be notified.

  FIG. 12 is a graph when the scheduled load is determined based on the scheduled load information notified from the management server and the processing performance is changed. The fluctuation of network traffic, the link-up speed, the processing performance, the planned load, and the planned load information when there is no bandwidth control are represented in time series. The link-up speed of the line is 10Gbps. In this embodiment, the scheduled load information of 10 Gbps is notified from the management server from time t1 to time t2, and the scheduled load information of 6 Gbps is notified at other times. This is for the purpose of reducing power consumption during a specific time when traffic can be expected to be reduced. In the management server, the optimum performance is reduced so that the planned load information at a specific time (time other than time t1 to time t2) is reduced. It is a case that is set. In this embodiment, the planned load information notified from the management server is determined as it is as the planned load of the line. As a result, the power consumption for a specific time can be reduced on the line.

  However, in the graph of FIG. 12, a load greater than the planned load occurs at time t3. In order to cope with such a case, in the network relay device that transmits the network traffic shown in FIG. 12, (10) a bandwidth control function, (11) a delay control function, and (12) a discard control function By combining with at least one of them, it becomes possible to transmit network traffic within the planned load range.

  It should be noted that at the specific time in FIG. 12 (time other than time t1 to time t2), it is only necessary to ensure processing performance according to the planned load, so the load of the functional block in each network LSI is determined based on the planned load. By doing so, power consumption can be reduced. Although the seven load determination methods A to G have been described above, it is possible not only to use each load determination function alone, but also to obtain a greater effect by using the load determination functions in combination.

  In particular, in contrast to “C. Load determination method based on planned load exchange between network relay devices”, “B. Load determination method based on circuit operation status determination” and “D. One or more of “E. Load determination method based on load information exchange between network LSIs” and “G. Load determination method based on scheduled load information notification of management server” When combined, it is considered that the accuracy of the load determination result used in the control information generation block 226 in the search LSI 103 can be improved.

  FIG. 13 illustrates the functions (10) to (12), “C. Load determination method based on scheduled load exchange between network relay devices”, “G. It is a graph at the time of making it operate | move in combination with "the load determination method based on scheduled load information notification. The graph of FIG. 13 shows network traffic fluctuation, scheduled load fluctuation, processing capacity fluctuation, link-up speed, and scheduled load information (upper limit) when there is a bandwidth control process based on the scheduled load fluctuation determination process. The fluctuation and the fluctuation of the planned load information (lower limit) are represented in time series. In this embodiment, two scheduled load information are shown, but the number of scheduled load information is not limited. As for the planned load fluctuation determination process, the planned load and the planned load fluctuation threshold are varied in units of 2 Gbps in the examples of FIGS. 9 and 10, but are varied in smaller units in this embodiment.

  Hereinafter, FIG. 13 will be described. In this embodiment, the scheduled load information (upper limit) of 10 Gbps is notified from the management server from time t1 to time t4, and the scheduled load information (upper limit) of 6 Gbps is notified at other times. Similarly, the scheduled load information (lower limit) of 4Gbps is notified from the management server from time t2 to time t3. At other times, 1Gbps scheduled load information (lower limit) is notified. In this embodiment, an upper limit value and a lower limit value at the time of planned load change are determined from a plurality of planned load information. Therefore, at time t2, the planned load increases regardless of the network traffic load, and at time t5, the planned load indicates a planned load with a value equal to the planned load information (upper limit) without being linked to the increase in network traffic. t6 indicates a planned load having a value equal to the planned load information (lower limit) without being linked to a decrease in network traffic. In order to perform such control, for example, in the step of notifying the scheduled load in FIG. 9 (S911, S931, S951, S960), it is determined whether the scheduled load to be notified is within the range between the upper limit value and the lower limit value. If the upper limit value is exceeded and the upper limit value is exceeded, the lower limit value may be notified as the scheduled load. By providing the upper limit value of the planned load, it is possible to reduce the power consumption in a time zone with a small amount of network traffic, and further, by providing the lower limit value of the planned load, it is possible to guarantee the minimum network traffic. Note that the network relay device only needs to secure processing performance according to the planned load, and therefore the load of the functional block in each network LSI is determined based on the planned load.

  In addition, in the network relay device that transmits network traffic at time t5, a combination of at least one of (10) bandwidth control function, (11) delay control function, and (12) discard control function is combined. By making it function, it becomes possible to transmit network traffic within the range of the planned load, and the decrease in reliability can be minimized in the network relay device in the low power consumption state.

  In the present invention, it is possible to determine the load for each channel (line) of each network LSI and the load of a functional block that implements a specific function from the load determination results obtained by these load determination methods. Further, the load on the functional block of each network LSI can be determined from the load for each channel (line), the load on the functional block that realizes the specific function, and the load on the maximum performance operation of the specific function block.

For this reason, the load of each functional block is determined by the ingress load on the channel, the load determined by the egress load of the channel, the load determined by the total load of all channels in the LSI, Judgment based on total ingress load on channel, judgment based on total egress load on all channels in LSI, judgment based on maximum ingress load on all channels in LSI, and all channels in LSI The function that determines whether the load is always determined to be maximum, the load that determines the ingress load is always determined to be maximum, the load that determines that the egress load is always determined to be maximum, It classify | categorizes into what is judged by. Table 1 shows a classification for each functional block in each network LSI.
(Table 1)

  By classifying in this way, it can be seen that the load of all functional blocks can be determined in the load determination control block of each network LSI. Based on this load determination result, the frequency voltage control block 228 of the search LSI 103, the frequency voltage control block 315 of the transfer LSI 104, and the frequency voltage control block 415 of the switch LSI 105 are clocked and operating voltage for each functional block of each LSI. By controlling at least one of them, power consumption can be reduced.

1 is a block diagram showing an overview of a network relay device 100 in an embodiment of the present invention. FIG. 3 is a diagram in which the inside of a search LSI 103 is divided into functional blocks. FIG. 3 is a diagram in which the inside of a transfer LSI 104 is divided into functional blocks. FIG. 3 is a diagram in which the inside of a switch LSI 105 is divided into functional blocks. It is a line state determination processing flowchart for each frame reception. It is a network traffic fluctuation graph (1) which does not implement a bandwidth control process. It is a network traffic fluctuation graph (1) which implements a bandwidth control process. It is a network traffic fluctuation graph (2) which does not implement a bandwidth control process. It is a plan load fluctuation determination processing flowchart. It is a network traffic fluctuation graph (2) which implements a bandwidth control process. It is a figure which shows the subnetwork comprised from a network relay apparatus and a management server. It is a graph (1) when the planned load is determined based on the planned load information notified from the management server and the processing performance is changed. It is a graph (2) when the planned load is determined based on the planned load information notified from the management server and the processing performance is changed.

Explanation of symbols

100 ・ ・ ・ Network relay device
101 ・ ・ ・ Transfer engine part
102 ... Central control unit
103 ・ ・ ・ Search LSI
104 ... Transfer LSI
105 ・ ・ ・ Switch LSI
201 ・ ・ ・ Downlink interface block
202 ・ ・ ・ Ingress side downlink block
203 ・ ・ ・ Egress side downlink block
204 ・ ・ ・ Ingress side line aggregation block
205 ・ ・ ・ Egress side line aggregation block
206 ... Search memory interface block
207 ... Search memory access block
211 ・ ・ ・ Buffer memory interface block
212 ... Buffer memory access block
216 ... Uplink interface block
217 ・ ・ ・ Ingress side uplink block
218 ... Egress side uplink block
219 Data processing block
220 ・ ・ ・ QoS control function block
221 ... Statistical function block
222 ・ ・ ・ Ingress side line load measurement block
223 ・ ・ ・ Frame analysis block
224 ・ ・ ・ Ingress load measurement block
225 ・ ・ ・ Egress load measurement block
226 ... Control information generation block
227 ... Frame transmission control block
228 Frequency / voltage control block
229 ... Load information transmission block
230 ・ ・ ・ Load judgment control block
301 ・ ・ ・ Downlink interface block
302 ・ ・ ・ Ingress side downlink block
303 ・ ・ ・ Egress side downlink block
304 ・ ・ ・ Ingress side downlink aggregation block
305 ・ ・ ・ Egress-side downlink aggregation block
306 ... Uplink interface block
307 ・ ・ ・ Ingress side uplink block
308: Egress side uplink block
309 ・ ・ ・ Ingress side uplink aggregation block
310 ・ ・ ・ Egress-side uplink aggregation block
311: Data processing block
312: Statistical function block
313 ・ ・ ・ Ingress load measurement block
314 ・ ・ ・ Egress load measurement block
315 ・ ・ ・ Frequency voltage control block
316 ・ ・ ・ Load information transmission block
317 ... Load judgment control block
401 ・ ・ ・ Ingress side interface block
402 ・ ・ ・ Ingress side data channel block
403 ・ ・ ・ Egress side interface block
404: Egress side data channel block
405 ・ ・ ・ Receive side control interface block
406 ・ ・ ・ Receive side control channel block
407 ... Transmitter side control interface block
408 ... Send side control channel block
409 ・ ・ ・ Ingress side channel aggregation block
410 ... Egress channel aggregation block
411 ... Data processing block
412 ... Statistical function block
413 ... Data load measurement block
414 ... Control load measurement block
415 ... Frequency voltage control block
416: Load information transmission block
417 ... Load judgment control block

Claims (17)

A network relay device connected to a plurality of lines and transferring data via the plurality of lines,
A central control unit for controlling the operation state of the network relay device;
A plurality of network LSIs connected to each other via a channel, and having a transfer engine unit for transferring data received from the line;
The network LSI includes a plurality of functional blocks for realizing the data transfer;
A load determination unit for determining a load applied to the functional block;
A network relay device comprising: a frequency voltage control unit that supplies a clock and an operating voltage to the functional block according to the determined load. The network relay device according to claim 1,
The central control unit determines an operation state of the line by analyzing a first control information frame received from the line,
The network relay device, wherein the load determination unit determines a load of a corresponding functional block according to the determined operation state of the line. The network relay device according to claim 1, wherein
The network LSI further analyzes a second control information frame storing information indicating a planned load of transmission traffic transmitted by another network relay device connected to the line, and determines the planned load of the line Frame analysis unit
The network relay device, wherein the load determination unit determines a load of a corresponding functional block according to a planned load of the line. The network relay device according to claim 3,
The network LSI further generates a third control information frame storing information indicating a scheduled load of transmission traffic to be transmitted to another network relay device connected to the line, and the other network relay A network relay device comprising a control information generation unit for transmitting to a device. The network relay device according to claim 4,
The network LSI further includes a frame transmission control unit that controls frame transmission to another network relay device connected to the line,
The network relay device, wherein the frame transmission control unit performs bandwidth control by controlling a transmission load according to a scheduled load of transmission traffic stored in the third control information frame. The network relay device according to claim 5,
The frame transmission control unit performs the band control after a predetermined time has elapsed after the control information generation unit transmits the third control information frame to the other network relay device. apparatus. The network relay device according to claim 5,
The frame transmission control unit receives the response frame from the other network relay device after the control information generation unit transmits the third control information frame to the other network relay device. A network relay device that performs control. The network relay device according to any one of claims 6 to 7,
The frame transmission control unit increases the transmission load stepwise when controlling the bandwidth by controlling the transmission load according to the planned load of the transmission traffic stored in the third control information frame. Network relay device to perform. The network relay device according to claim 5, wherein
The network transmission apparatus, wherein the frame transmission control unit performs priority control such as delay control and discard control according to frame priority. The network relay device according to claim 1, wherein
The central control unit monitors a link up state including information on whether or not the line is linked up,
The network relay device, wherein the load determination unit determines a load of a corresponding functional block according to the monitored link up state. The network relay device according to claim 10,
The network relay device, wherein the link-up state further includes information on a line speed of the line that is linked up. The network relay device according to claim 10 to 11, comprising:
The network relay device, wherein the load determination unit determines a load of a corresponding functional block from a link up state of a plurality or all of the lines. The network relay device according to claim 10 to 11, comprising:
The network LSI further includes a load information transmission unit for exchanging load information of the functional block determined from the link-up state or the link-up state with another network LSI,
The load determining unit determines a load of a functional block of a specific network LSI from the link-up state or the load information for a plurality or all of the lines exchanged by the load information transmitting unit. Relay device. The network relay device according to claim 1, wherein
The central control unit determines an unused function from the operation state of the network relay device,
The network relay device, wherein the load determination unit determines a load of a corresponding functional block according to the determined unused function. The network relay device according to claim 1, wherein
The network relay device, wherein the central control unit determines a planned load of the line and a load of a corresponding functional block based on planned load information notified from a management server inside or outside the device. The network relay device according to claim 4, wherein
The central control unit receives notification of the upper limit value and the lower limit value of the planned load information from the management server inside or outside the device,
The network relay device characterized in that the control information generation unit stores a scheduled load within the range of the upper limit value and the lower limit value in the third control information frame and transmits it to the other network relay device. The network relay device according to any one of claims 1 to 16,
The transfer engine unit further includes an ingress side load measurement unit and an egress side load measurement unit,
The network relay device, wherein the load determination unit determines a load of a corresponding functional block based on a load measured by at least one of the ingress side load measurement unit and the egress side load measurement unit.

Images