JP2010109475A - Network apparatus, information processing method for virtualizing resource, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To temporarily store a layer 2 frame received by its own network apparatus in other apparatus without interrupting original data transmission processing in the other apparatus. <P>SOLUTION: The network apparatus has: a buffer; a receiving means for successively receiving layer 2 frames; a first determination means for determining whether the empty capacity of the buffer exceeds a first threshold; a means which, when the first determination means determines that the empty capacity of the buffer exceeds the first threshold, stores the received layer 2 frames in the buffer; and a transfer means which, when the first determination means determines that the empty capacity of the buffer is lower than the first threshold, generates transfer data including the received layer 2 frames and transfer data including a prescribed header different from the headers of the layer 2 frames and transfers the generated transfer data to other network apparatus in which the temporary storage of the layer 2 frames instead of the network apparatus is preset. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present technology relates to the field of resource virtualization technology in a network system.

  In recent years, a network environment is composed of a plurality of network devices, server devices, and the like, and the scale continues to increase year by year. As a means for maintaining the quality of the network environment, a network monitoring / management apparatus that implements a function of collecting various log information for early identification and cause investigation when a network failure occurs has attracted attention.

  Conventionally, in such a network device, when the capacity of a buffer prepared for storing log information is exceeded, the log information is overwritten in order from the oldest one or the subsequent log information is discarded. It was. Alternatively, in order to avoid buffer overflow, only representative information is stored as log information, and information other than representative information is discarded.

  On the other hand, in recent years, threats to networks such as computer viruses and worms, malicious programs, unauthorized access, spyware, and framing have become more sophisticated and complex year by year. As countermeasures against such threats, worm detection / disinfection and movement are realized by implementing real-time analysis of upper layer and combination of multiple packets (sequence, sequence control, etc.) from conventional lower layer and per-packet filtering. Enhancement of functions such as automatic intrusion detection and prevention is required.

  However, the speed of the physical line bandwidth is also increasing, and if the processing capacity of the network device cannot catch up and the buffer capacity overflows, as described above, the old one may be overwritten or the amount of overflow The entire traffic cannot be analyzed because the information is discarded. Further, as described above, threats to the network are becoming more sophisticated and complex year by year, and there are cases where these threats cannot be detected only by representative information.

  Conventionally, there is a technique for temporarily saving a received frame to another device when the buffer of the own device is low. Specifically, when the own device transfers a received frame to another device, the device transfers the frame after inserting a tag indicating that the frame is sent back. In another apparatus, when the tag described above is inserted in the received frame, the frame is returned to the same port as the reception port. In order to prevent frame looping, a pause frame for stopping data transmission processing from the own device to another device until the predetermined time has elapsed until the buffer of the own device reaches a predetermined amount. Is sent regularly. When the transmission of the pause frame is stopped, the frame returns from the other device to the own device, and the temporary saving becomes possible.

However, in this prior art, another device cannot perform any data transmission processing while receiving a pause frame from itself. Therefore, if the other device is a standby device, the frame may be temporarily saved, but if the other device is an active device, the original data transmission processing in the other device is obstructed. The problem of doing will arise.
Japanese Patent Laid-Open No. 2005-210385

  Therefore, an object of the present technology is to allow a frame received by the own apparatus to be temporarily stored in the other apparatus without hindering an original data transmission process in the other apparatus.

  The network device includes: a buffer; a receiving unit that sequentially receives layer 2 frames; a first determining unit that determines whether the free space of the buffer exceeds a first threshold; and the free space of the buffer in the first determining unit. When it is determined that the first threshold value is exceeded, the means for storing the received layer 2 frame in the buffer and the first determining means that the buffer free space is determined to be below the first threshold value It is preset that transfer data including the received layer 2 frame and a predetermined header different from the header of the layer 2 frame is generated and the layer 2 frame is temporarily stored instead of the network device. Transfer means for transferring to another network device.

  The layer 2 frame received by the own device can be temporarily stored in the other device without hindering the original data transmission processing in the other device.

[Outline of Embodiment of this Technology]
First, an outline of an embodiment of the present technology will be described with reference to FIGS. For example, as shown in FIG. 1, it is assumed that a network system is constructed by network devices A to D. In such a network system, it is assumed that the network apparatus A sequentially receives frames (layer 2 frames) via a physical line and analyzes the received frames in order to detect worms and unauthorized intrusion. Here, for example, when the bandwidth of the physical line is 10 Gbps, and the burst load as shown in FIG. 2 is applied, the amount of received frames is the processing capacity of the CPU of the network device A (here, 8G). The amount of frames stored in the buffer increases and eventually the buffer capacity overflows.

  Therefore, in the present embodiment, when the free space of the buffer falls below the first threshold (that is, when the buffer usage exceeds the overflow threshold), as shown in FIG. Transfer to network devices (network devices B to D). In the present embodiment, a header other than the layer 2 header is added to the frame, and the frame is transferred to another network device.

  On the other hand, when the amount of frames to be received becomes smaller than the processing capability of the CPU of the network device A, the amount of frames stored in the buffer also decreases, and the buffer free space increases. When the buffer free capacity falls below the second threshold (that is, when the buffer usage falls below the recovery threshold), as shown in FIG. 3, the frame transferred to another network device is transferred to the network device A. Return to. This makes it possible to analyze all received frames even when the buffer capacity overflows.

[Embodiment 1]
A first embodiment of the present technology will be described with reference to FIGS. 4 to 22. In the first embodiment, when a frame is transferred to another network device, an FTP (File Transfer Protocol) header is added and the frame is transferred to another network device.

  FIG. 4 shows a system configuration diagram according to the first embodiment. For example, a plurality of servers (servers A to C in FIG. 4) and a network device 3A are connected to the network 1 that is the Internet. A network system 30 is constructed by the network devices 3A to 3D, and each network device is connected via a network 11 such as an in-house (Local Area Network). Note that a user terminal (not shown) is connected to each network device. Further, it is assumed that the network devices 3B to 3D are devices that are preset to temporarily store frames instead of the network device 3A.

  FIG. 5 shows a functional block diagram of the network device 3A shown in FIG. The network device 3A determines whether the buffer 311, the frame receiving unit 301 that sequentially receives frames transmitted via the network 1, and the free capacity of the buffer 311 exceeds the first threshold, and the free space of the buffer 311 When the capacity exceeds the first threshold value, the first determination processing unit 302 that stores the frame received by the frame receiving unit 301 in the buffer 311 and the frame stored in the buffer 311 are sequentially read, and the frame A frame processing unit 303 that performs analysis processing, a resource management table storage unit 304 that stores a resource management table to be described later, and an operation status and resource information from each of other network devices periodically or at an arbitrary timing And the resource stored in the resource management table storage unit 304 The free capacity of the buffer 311 is below the first threshold by the resource management unit 305 that updates the management table, the transfer management table storage unit 306 that stores the transfer management table described later, and the first determination processing unit 302. If it is determined that the received frame is transferred to another network device according to the resource management table stored in the resource management table storage unit 304, the transfer management table is stored. A frame transfer unit 307 that adds a record to the transfer management table stored in the unit 306; and a second that determines whether the free capacity of the buffer 311 falls below a second threshold when the record is registered in the transfer management table. The free space of the buffer 311 is determined by the determination processing unit 308 and the second determination processing unit 308. When it is determined that the threshold value is less than 2, a process for acquiring a frame from another network device is performed according to the transfer management table stored in the transfer management table storage unit 306, and the frame is stored in the buffer 311. It has a frame acquisition unit 309 to store, and a transfer data processing unit 310 that receives transfer data, which will be described later, from another network device and stores it in the buffer 311. The network devices 3B to 3D basically have the same configuration as the network device 3A.

  FIG. 6 shows an example of a resource management table stored in the resource management table storage unit 304. FIG. 6 is an example of a resource management table in the network device 3A. In the example of FIG. 6, the resource management table includes a column for another device, a column for the operating status (1: active / 0: stopped), and a column for the buffer amount (unit: “GB (giga bytes)”). , A column of buffer usage rate (unit: “%”), a column of remaining buffer capacity (unit: “GB”), a column of CPU processing capacity (unit: “pps (Packet Per Second)”), and CPU usage Column of rate (unit: “%”), column of remaining CPU processing capacity (unit: “pps”), column of physical line bandwidth (unit: “Mbps (megabit per second)”), and physical line usage And a column of the remaining physical line amount (unit: “Mbps”). The buffer amount, CPU processing capability, and physical line bandwidth in each network device are set in advance in the buffer amount column, CPU processing capability column, and physical line bandwidth column. The operation status column, buffer usage rate column, CPU usage rate column, and physical line usage column include the operating status and resource information (that is, buffer usage rate, CPU usage rate) acquired from each network device. And physical line usage) are set. Further, as will be described in detail later, values calculated by the resource management unit 305 are set in the column for the remaining buffer capacity, the column for the remaining CPU processing capacity, and the column for the remaining physical line amount.

  FIG. 7 shows an example of a transfer management table stored in the transfer management table storage unit 306. In the example of FIG. 7, the transfer management table includes a file name column, a start frame number column, an end frame number column, and a transfer destination column. Although details will be described later, in the first embodiment, transfer data including several received frames (which may be one) and an FTP header is generated, and the transfer data is generated by an FTP put command. Transfer to another network device. Here, an arbitrary file name given at the time of transfer by the FTP put command is set in the file name column. In the column of the start frame number, the frame number of the first frame included in the transfer data is set. Further, in the end frame number column, the frame number of the last frame included in the transfer data is set. In the transfer destination column, another network device that has transferred the transfer data is set.

  Next, an outline of processing in the first embodiment will be described with reference to FIGS. First, the processing when the free capacity of the buffer 311 exceeds the first threshold value (that is, when the usage amount of the buffer 311 falls below the overflow threshold value) will be described with reference to FIG. In this case, the received frames are sequentially stored in the buffer 311 in the network device 3A. On the other hand, the frame processing unit 303 sequentially reads frames from the buffer 311 and performs processing such as frame analysis. The shaded arrows represent the flow of frames.

  Next, a process when the free capacity of the buffer 311 falls below the first threshold (that is, when the usage amount of the buffer 311 exceeds the overflow threshold) will be described with reference to FIGS. The frame receiving unit 301 of the network device 3A receives the frames 1 to 10. Here, when the first determination processing unit 302 of the network device 3A determines that the free capacity of the buffer 311 is less than the first threshold, the frame transfer unit 307 of the network device 3A uses several received frames ( In FIG. 9, transfer data including frames 1 to 10) and an FTP header is generated. Then, the frame transfer unit 307 of the network device 3A includes (a) operating status, (b) remaining buffer capacity, (c) remaining CPU processing capacity, and (d) remaining physical line stored in the resource management table. Based on the amount, the network device with the most available resources is identified as the transfer destination. Specifically, for each network device, the value of (a) × (b) × (c) × (d) is calculated, and the network device having the largest calculated value is specified.

  For example, when data as shown in FIG. 10 is stored in the resource management table, the value of (a) × (b) × (c) × (d) in the network device 3B is 125000 (= 1 × 50 × 50 × 50). The value of (a) × (b) × (c) × (d) in the network device 3C is 6300 (= 1 × 70 × 1 × 90). Furthermore, the value of (a) × (b) × (c) × (d) in the network device 3D is 35000 (= 1 × 50 × 10 × 70). That is, here, the network device 3B is specified as the transfer destination.

  Then, the frame transfer unit 307 of the network device 3A transfers the transfer data “AAA” to the network device 3B by the FTP put command. Then, the frame transfer unit 307 of the network device 3A stores a record including information related to the transfer data (file name “AAA”, start frame number “1”, end frame number “10”, transfer destination “network device 3B”). Add to the transfer management table.

  On the other hand, since the network device 3B receives the transfer data “AAA” and stores it in the buffer 311 of the network device 3B, the buffer usage rate of the network device 3B increases. Note that the buffer usage rate of the network device 3B is reflected in the resource management table of the network device 3A by the resource management unit 305 of the network device 3A, for example, as shown in FIG.

  Moving to the description of FIG. 12, when the network device 3A further receives the frames 11 to 15, the frame transfer unit 307 of the network device 3A generates transfer data including these received frames and the FTP header. Then, as described above, the transfer destination network device is specified. For example, when the data shown in FIG. 11 is stored in the resource management table, the value of (a) × (b) × (c) × (d) in the network device 3B is 32500 (= 1 × 13 × 50 × 50). The value of (a) × (b) × (c) × (d) in the network device 3C is 6300 (= 1 × 70 × 1 × 90). Furthermore, the value of (a) × (b) × (c) × (d) in the network device 3D is 35000 (= 1 × 50 × 10 × 70). That is, here, the network device 3D is specified as the transfer destination.

  Then, the frame transfer unit 307 of the network device 3A transfers the transfer data “BBB” to the network device 3D by the FTP put command. Then, the frame transfer unit 307 of the network device 3A stores a record including information related to the transfer data (file name “BBB”, start frame number “11”, end frame number “15”, transfer destination “network device 3D”). Add to the transfer management table.

  On the other hand, since the network device 3D receives the transfer data “BBB” and stores it in the buffer 311 of the network device 3D, the buffer usage rate of the network device 3D increases. Note that the buffer usage rate of the network device 3D is reflected in the resource management table of the network device 3A by the resource management unit 305 of the network device 3A, for example, as shown in FIG.

  Next, processing when the free capacity of the buffer 311 exceeds the second threshold value (that is, when the usage amount of the buffer 311 falls below the recovery threshold value) will be described with reference to FIGS. 14 and 15. 14 is a continuation of the processing in FIG. When the second determination processing unit 308 of the network device 3A determines that the free capacity of the buffer 311 has fallen below the second threshold, the frame acquisition unit 309 of the network device 3A reads one record from the transfer management table, Transfer data related to the record is acquired by the FTP get command. For example, as shown in FIG. 14, the transfer data “AAA” is acquired from the network device 3B. Then, the frame acquisition unit 309 of the network device 3A stores the frames (frame 1 to frame 10) included in the acquired transfer data in the buffer 311 of the network device 3A.

  Shifting to the description of FIG. 15, the frame acquisition unit 309 of the network device 3 </ b> A reads one next record from the transfer management table, and acquires transfer data related to the record by an FTP get command. For example, as shown in FIG. 15, transfer data “BBB” is acquired from the network device 3D. Then, the frame acquisition unit 309 of the network device 3A stores the frames (frame 11 to frame 15) included in the acquired transfer data in the buffer 311 of the network device 3A.

  Next, the processing of the network device 3A that performs the processing described above will be described in more detail with reference to FIGS. Hereinafter, for convenience of explanation, the network device 3A may be referred to as “own device”, and the network devices 3B to 3D may be referred to as “other devices”. First, the process of acquiring the operating status and resource information from another device will be described with reference to FIGS. 16 and 17. For example, the resource management unit 305 of the own apparatus performs processing as shown in FIG. 16 periodically or at an arbitrary timing. The resource management unit 305 of its own device pings each other device and updates the operating status of the resource management table (FIG. 16: step S1). Specifically, as shown in FIG. 17, when there is a response to the ping transmission, it is determined that it is in operation (1), and when there is no response to the ping transmission, it is determined to be stopped (0). .

  Then, the resource management unit 305 of the own device acquires the buffer usage rate, the CPU usage rate, and the physical line usage amount from each other device, and stores them in the resource management table (step S3). For example, as shown in FIG. 17, the resource information is acquired by using an SNMP (Simple Network Management Protocol) get command.

  Then, the resource management unit 305 of the own device calculates the remaining buffer amount, remaining CPU processing capacity, and remaining physical line amount of each other device, stores them in the resource management table (step S5), and ends this processing. Here, “buffer amount− (buffer amount × buffer usage rate)” is calculated as the remaining buffer amount. Further, “CPU processing capacity− (CPU processing capacity × CPU usage rate)” is calculated as the remaining CPU processing capacity. Further, “physical line bandwidth−physical line usage” is calculated as the remaining physical line quantity.

  As described above, by periodically collecting the resource information of each other device, it becomes possible to transfer the transfer data to the other device having the most free resources in the processing described later.

  Next, processing when a frame is received will be described with reference to FIGS. The frame receiving unit 301 of the own device receives the frame transmitted via the network 1 (FIG. 18: step S11). Then, the first determination processing unit 302 of the own device determines whether the free capacity of the buffer 311 of the own device exceeds the first threshold (step S13). When it is determined that the free capacity of the buffer 311 of the own device exceeds the first threshold (step S13: Yes route), the first determination processing unit 302 of the own device stores the received frame in the buffer 311 ( Step S15). Thereafter, the process ends.

  On the other hand, when it is determined that the free capacity of the buffer 311 of the own device is below the first threshold (step S13: No route), the frame transfer unit 307 of the own device stores the data stored in the resource management table. Based on this, a frame transfer process is performed (step S17), and this process ends. Details of the frame transfer process will be described with reference to FIG.

  First, the frame transfer unit 307 combines several frames, adds an FTP header, and generates transfer data (FIG. 19: step S21). Then, the frame transfer unit 307 specifies the transfer destination based on the data stored in the resource management table (step S23). Specifically, as described above, (a) operating status, (b) remaining buffer capacity, (c) remaining CPU processing capacity, and (d) remaining physical line stored in the resource management table. Using the amount, the value of (a) × (b) × (c) × (d) is calculated for each other device, and the other device having the largest calculated value is specified as the transfer destination.

  Then, the frame transfer unit 307 transfers the transfer data to the other device of the transfer destination by the FTP put command (step S25). At this time, an arbitrary file name is given to the transfer data. Then, the frame transfer unit 307 transfers and manages a record including an arbitrary file name given to the transfer data, the frame numbers of the first frame and the last frame included in the transfer data, and the other device of the transfer destination. It adds to the table (step S27). Thereafter, the frame transfer process is terminated and the process returns to the original process.

  By performing the processing as described above, the transfer data including the FTP header is transferred, so that control at the layer 2 level becomes unnecessary. That is, the frame received by the own device can be temporarily stored in the other device without obstructing the data transmission process of the other device.

  Next, processing when the free capacity of the buffer 311 of the own apparatus falls below the first threshold and then exceeds the second threshold will be described with reference to FIGS. The second determination processing unit 308 of its own apparatus performs processing as shown in FIG. 20 periodically or at an arbitrary timing. The second determination processing unit 308 of its own device determines whether a record is registered in the transfer management table (FIG. 20: step S31). When it is determined that the record is registered in the transfer management table (step S31: Yes route), the second determination processing unit 308 of the own device has the free capacity of the buffer 311 of the own device exceeding the second threshold. (Step S33). When it is determined that the free capacity of the buffer 311 of the own device exceeds the second threshold (step S33: Yes route), the frame acquisition unit 309 of the own device performs frame acquisition processing based on the transfer management table. Then (step S35), the process returns to step S31. The frame acquisition process will be described with reference to FIG.

  First, the frame acquisition unit 309 reads one record from the transfer management table (FIG. 21: step S41). When a plurality of records are registered, the record including the oldest frame number is read out. Then, the frame acquisition unit 309 extracts a file name and a transfer destination from the read record (step S43), and acquires transfer data related to the file name from another apparatus at the transfer destination by an FTP get command (step S45). Then, the frame acquisition unit 309 stores each frame included in the acquired transfer data in the buffer 311 of the own device in the order of the frame number (step S47). Then, the frame acquisition unit 309 deletes the read record from the transfer management table (step S49), and returns to the original process.

  Returning to the description of FIG. 20, when it is determined that no record is registered in the transfer management table (step S31: No route), or the free capacity of the buffer 311 of the own apparatus is lower than the second threshold value. Is determined (step S33: No route), the process is terminated.

  By performing the processing as described above, frames temporarily stored in other devices can be returned to the own device when the free capacity of the buffer 311 of the own device exceeds a certain amount. As a result, the own apparatus can perform processing such as analysis for all frames.

  Next, processing in another apparatus will be described with reference to FIG. First, the transfer data processing unit 310 of the other apparatus determines whether transfer data has been received (FIG. 22: step S51). That is, it is determined whether a transfer request by the FTP put command is received. If transfer data has not been received (step S51: No route), the process proceeds to step S55. On the other hand, when the transfer data is received (step S51: Yes route), the transfer data processing unit 310 of the other device stores the transfer data in the buffer 311 of the other device (step S53). Thereafter, the process proceeds to step S55.

  Then, the transfer data processing unit 310 of the other device determines whether a return request has been received (step S55). That is, it is determined whether an acquisition request by the FTP get command has been received. If no return request has been received (step S55: No route), this process ends. On the other hand, when the return request is received (step S55: Yes route), the transfer data processing unit 310 of the other apparatus reads the transfer data related to the return request from the buffer 311 and transmits it to the request source (step S57). Thereafter, this process is terminated.

  As described above, according to the present embodiment, since transmission / reception with another device is performed by FTP transfer, original data transmission processing in the other device is not hindered. That is, even if the other apparatus is an active apparatus, the layer 2 frame can be temporarily saved. Also, since layer 2 frames are transferred in a distributed manner according to the resource status of other devices, the entire network device group temporarily saves layer 2 frames without causing problems such as buffer capacity overflow. You can also

[Embodiment 2]
Next, a second embodiment of the present technology will be described with reference to FIGS. The system configuration in the second embodiment is basically the same as that shown in FIG. The functional block diagram of the network device 3A in the second embodiment is basically the same as that shown in FIG.

  In the second embodiment, data as shown in FIG. 23 is stored in the transfer management table. In the example of FIG. 23, the transfer management table includes a frame number column and a transfer destination column.

  An outline of processing in the second embodiment will be described with reference to FIGS. Note that the processing when the free capacity of the buffer 311 exceeds the first threshold (that is, when the usage amount of the buffer 311 is below the overflow threshold) is the processing described in the first embodiment (FIG. Since this is the same as 8), the description is omitted here.

  First, the processing when the free capacity of the buffer 311 falls below the first threshold (that is, when the usage amount of the buffer 311 exceeds the overflow threshold) will be described with reference to FIGS. The frame reception unit 301 of the network device 3A receives the frames 1 to 3. Here, when the first determination processing unit 302 of the network device 3A determines that the free capacity of the buffer 311 is less than the first threshold, the frame transfer unit 307 of the network device 3A Transfer data (a save frame) including a received frame and a unique header is generated. In the second embodiment, a header as shown in FIG. 25 is used instead of the FTP header. As shown in FIG. 25A, the header includes a status code (2 bits) and a frame number (No.) (6 bits). As shown in FIG. 25B, the status code includes “00” indicating a normal frame, “01” indicating a save frame, and “01” indicating a return request frame. One of “10” and “11” representing a return frame is set. That is, in FIG. 24, “01” is set as the status code.

  Then, the frame transfer unit 307 of the network device 3A includes (a) operating status, (b) remaining buffer capacity, (c) remaining CPU processing capacity, and (d) remaining physical line stored in the resource management table. Based on the amount, the network device with the most available resources is identified as the transfer destination. Note that the transfer destination specifying process is the same as the process described in the first embodiment, and a description thereof will be omitted here. It is assumed that the network device 3B is specified as the transfer destination.

  Then, the frame transfer unit 307 of the network device 3A transfers the transfer data (save frame) to the network device 3B, and adds a record including information (frame number and transfer destination) regarding the transfer data to the transfer management table.

  On the other hand, since the network device 3B receives the transfer data (save frame) and stores it in the buffer 311 of the network device 3B, the buffer usage rate of the network device 3B increases. Note that the buffer usage rate of the network device 3B is reflected in the resource management table of the network device 3A by the resource management unit 305 of the network device 3A, and becomes, for example, the data shown in FIG.

  Moving to the description of FIG. 26, when the network device 3A further receives the frames 4 to 6, the frame transfer unit 307 of the network device 3A for each received frame, the received frame and the header shown in FIG. Transfer data (save frame) including is generated. Then, as described above, the transfer destination network device is specified. Here, it is assumed that the network device 3D is specified as the transfer destination.

  Then, the frame transfer unit 307 of the network device 3A transfers the transfer data (save frame) to the network device 3D, and adds a record including information (frame number and transfer destination) related to the transfer data to the transfer management table.

  On the other hand, since the network device 3D receives the transfer data (save frame) and stores it in the buffer 311 of the network device 3D, the buffer usage rate of the network device 3D increases. Note that the buffer usage rate of the network device 3D is reflected in the resource management table of the network device 3A by the resource management unit 305 of the network device 3A and becomes, for example, the data shown in FIG.

  Next, processing when the free capacity of the buffer 311 exceeds the second threshold value (that is, when the usage amount of the buffer 311 falls below the recovery threshold value) will be described with reference to FIGS. 27 and 30. 27 is a continuation of the process in FIG. When the second determination processing unit 308 of the network device 3A determines that the free capacity of the buffer 311 has fallen below the second threshold, the frame acquisition unit 309 of the network device 3A sequentially reads records from the transfer management table (FIG. 27). In this example, it is assumed that records relating to frame numbers “1” to “3” have been read), and for each read record, a return request frame including the status code “10” and the frame number relating to the record is networked. Transmit to device 3B.

  28, when the network device 3B receives the return request frame from the network device 3A, the transfer including the frame corresponding to the frame number included in the return request frame and the header shown in FIG. Data (return frame) is generated and transmitted to the network device 3A. The header status code is set to “11”, and the frame number (No.) is set to the frame number included in the return request frame.

  The frame acquisition unit 309 of the network device 3A receives the transfer data (return frame) and stores the frame included in the transfer data in the buffer 311 of the network device 3A.

  Shifting to the explanation of FIG. 29, the frame acquisition unit 309 of the network device 3A further reads out the record from the transfer management table (in FIG. 29, the records related to the frame numbers “4” to “6” are read out). For each read record, a return request frame including the status code “10” and the frame number related to the record is transmitted to the network device 3D.

  Moving to the description of FIG. 30, when the network device 3D receives the return request frame from the network device 3A, the transfer including the frame corresponding to the frame number included in the return request frame and the header shown in FIG. Data (return frame) is generated and transmitted to the network device 3A. The header status code is set to “11”, and the frame number (No.) is set to the frame number included in the return request frame.

  The frame acquisition unit 309 of the network device 3A receives the transfer data (return frame) and stores the frame included in the transfer data in the buffer 311 of the network device 3A.

  Next, the processing of the network device 3A that performs the processing described above will be described in more detail with reference to FIGS. Note that the processing contents are basically the same as those described in the first embodiment. However, in the second embodiment, a process (see FIG. 31) (instead of the frame transfer process shown in FIG. 19) (Referred to as frame transfer processing 2). Further, instead of the frame acquisition process shown in FIG. 21, a process as shown in FIG. 32 (referred to as frame acquisition process 2) is performed. Further, in another apparatus, a process as shown in FIG. 33 is performed instead of the process shown in FIG. Hereinafter, each process will be described.

  First, the frame transfer process 2 will be described with reference to FIG. The frame transfer unit 307 of its own apparatus sets a code “01” indicating that it is a save frame in its own header (FIG. 31: step S61). Then, transfer data (evacuation frame) is generated by adding a predetermined header to the received frame (step S63). Then, the frame transfer unit 307 specifies the transfer destination based on the data stored in the resource management table (step S65). Since this process is not different from the process of step S23, detailed description thereof is omitted here.

  Then, the frame transfer unit 307 transfers the transfer data (save frame) to the other device at the transfer destination (step S67). Then, the frame transfer unit 307 adds a record including the frame number of the frame included in the transfer data and the transfer destination other device to the transfer management table (step S69). Thereafter, the frame transfer process is terminated and the process returns to the original process.

  Next, the frame acquisition process 2 will be described with reference to FIG. The frame acquisition unit 309 of its own apparatus reads one record from the transfer management table (FIG. 32: step S71). When a plurality of records are registered, the record including the oldest frame number is read out. Then, the frame acquisition unit 309 extracts a transfer destination and a frame number from the read record (step S73). Then, the frame acquisition unit 309 generates a return request frame including the extracted frame number and transmits it to the extracted transfer destination (step S75).

  Thereafter, the frame acquisition unit 309 receives the transfer data (return frame) (step S77), removes a predetermined header from the received transfer data, and stores the frame in the buffer 311 of the own apparatus (step S79). Then, the frame acquisition unit 309 deletes the read record from the transfer management table (step S81), and returns to the original process.

  Next, processing in another apparatus will be described with reference to FIG. First, the transfer data processing unit 310 of the other apparatus determines whether transfer data (a save frame) has been received (FIG. 33: step S91). If transfer data (a save frame) has not been received (step S91: No route), the process proceeds to step S95. On the other hand, when transfer data (evacuation frame) is received (step S91: Yes route), the transfer data processing unit 310 of the other device stores the transfer data (evacuation frame) in the buffer 311 of the other device (step S93). Thereafter, the process proceeds to step S95.

  Then, the transfer data processing unit 310 of the other device determines whether a return request frame has been received (step S95). If no return request frame has been received (step S95: No route), this process ends. On the other hand, when the return request frame is received (step S95: Yes route), the transfer data processing unit 310 of the other device extracts the frame number from the return request frame (step S97), and selects the frame corresponding to the extracted frame number. Reading from the buffer 311 (step S99). Then, the transfer data processing unit 310 of the other device generates transfer data (return frame) by adding a header to the read frame (step S101). Then, the transfer data processing unit 310 of the other apparatus transmits the transfer data to the request source (step S103). Thereafter, this process is terminated.

  By performing the processing as described above, even if a unique header is used instead of the FTP header, the own device does not hinder the data transmission processing of other devices, as in the first embodiment. The frame received in step 1 can be temporarily stored in another device.

  Although the embodiment of the present technology has been described above, the present technology is not limited to this. For example, the functional block diagram of the network device 3A described above does not necessarily correspond to an actual program module configuration.

  Further, the configuration of each table described above is an example, and the configuration as described above is not necessarily required. Further, in the processing flow, the processing order can be changed if the processing result does not change. Further, it may be executed in parallel.

  The embodiments of the present technology described above can be summarized in the following modes.

  The network device includes: a buffer; a receiving unit that sequentially receives layer 2 frames; a first determining unit that determines whether the free space of the buffer exceeds a first threshold; and the free space of the buffer in the first determining unit. When it is determined that the first threshold value is exceeded, the means for storing the received layer 2 frame in the buffer and the first determining means that the buffer free space is determined to be below the first threshold value It is preset that transfer data including the received layer 2 frame and a predetermined header different from the header of the layer 2 frame is generated and the layer 2 frame is temporarily stored instead of the network device. Transfer means for transferring to another network device.

  In this way, since transfer data including a header different from the header of the layer 2 frame is transferred, control at the layer 2 level becomes unnecessary. That is, the layer 2 frame received in the network device can be temporarily stored in the other network device without hindering the data transmission process of the other network device.

  Further, after the first determination means determines that the free space of the buffer is below the first threshold, the second determination means determines whether the free space of the buffer exceeds the second threshold, and the second determination means When it is determined that the free space of the buffer has exceeded the second threshold value, the transfer data is acquired from another network device, and the acquisition unit stores the layer 2 frame included in the transfer data in the buffer. It may be. In this way, when the free space of the buffer exceeds a certain amount, the layer 2 frame stored in the other network device returns to the network device. In this case, all layer 2 frames can be processed.

  In addition, when there are a plurality of other network devices, there may be further provided means for acquiring the operating status and resource information from each of the plurality of other network devices at a predetermined timing. The transfer means described above includes a means for specifying a device that is in operation and has the most available resources among a plurality of other network devices as a transfer destination, and a layer 2 frame frame included in the transfer data. Means for storing the number and information indicating the transfer destination in the transfer management table, and the acquisition means described above transfers the transfer data according to the frame number and the information indicating the transfer destination stored in the transfer management table. You may make it have a means to acquire. In this way, since the layer 2 frame is transferred in a distributed manner in accordance with the state of the resources of other network devices, the network device group as a whole does not suffer from problems such as buffer capacity overflow or the like. The frame can be temporarily retracted.

  Furthermore, the predetermined header described above may be an FTP header. In addition, the predetermined header described above may be a header including a frame type and a frame number.

  A program for realizing the above apparatus together with hardware can be created, and the program is stored in a storage medium or storage device such as a flexible disk, a CD-ROM, a magneto-optical disk, a semiconductor memory, or a hard disk. The The intermediate processing result is temporarily stored in a storage device such as a main memory.

(Appendix 1)
A network device,
A buffer,
Receiving means for sequentially receiving layer 2 frames;
First determination means for determining whether the free space of the buffer exceeds a first threshold;
Means for storing the received layer 2 frame in the buffer when the first determining means determines that the free capacity of the buffer exceeds the first threshold;
When the first determination means determines that the free space of the buffer is below the first threshold, the received layer 2 frame and a predetermined header different from the header of the layer 2 frame Transfer means for generating transfer data including, and transferring to another network device that is preset to temporarily store the layer 2 frame instead of the network device;
A network device.

(Appendix 2)
Second judging means for judging whether or not the free capacity of the buffer exceeds a second threshold after it is judged in the first judging means that the free capacity of the buffer is lower than the first threshold;
When the second determination means determines that the free space of the buffer exceeds the second threshold, the transfer data is acquired from the other network device, and the layer 2 frame included in the transfer data is stored in the layer 2 frame. Acquisition means for storing in a buffer;
The network device according to appendix 1, further comprising:

(Appendix 3)
Means for acquiring operation status and resource information from each of the plurality of other network devices at a predetermined timing when there are a plurality of the other network devices;
The transfer means is
A unit that identifies, as a transfer destination, a device that is in operation and has the most available resources among the plurality of other network devices;
Means for storing a frame number of the layer 2 frame included in the transfer data and information indicating a transfer destination in a transfer management table;
Have
The acquisition means is
The network device according to appendix 2, further comprising means for acquiring the transfer data according to the frame number stored in the transfer management table and information indicating the transfer destination.

(Appendix 4)
The network device according to any one of appendices 1 to 3, wherein the predetermined header is an FTP header.

(Appendix 5)
The network apparatus according to any one of appendices 1 to 3, wherein the predetermined header is a header including a frame type and a frame number.

(Appendix 6)
An information processing method for virtualizing resources executed by a network device,
Sequentially receiving layer 2 frames;
A determination step of determining whether a free space of a buffer in the network device exceeds a first threshold;
Storing the received layer 2 frame in the buffer when it is determined in the determining step that the free space of the buffer exceeds the first threshold;
When it is determined in the determination step that the free space of the buffer is lower than the first threshold, the transfer including the received layer 2 frame and a predetermined header different from the header of the layer 2 frame Generating data and transferring it to another network device preset to temporarily store the layer 2 frame instead of the network device;
An information processing method for virtualizing resources, including:

(Appendix 7)
A program for causing a network device to execute processing for virtualizing resources,
Sequentially receiving layer 2 frames;
A determination step of determining whether a free space of a buffer in the network device exceeds a first threshold;
Storing the received layer 2 frame in the buffer when it is determined in the determining step that the free space of the buffer exceeds the first threshold;
When it is determined in the determination step that the free space of the buffer is lower than the first threshold, the transfer including the received layer 2 frame and a predetermined header different from the header of the layer 2 frame Generating data and transferring it to another network device preset to temporarily store the layer 2 frame instead of the network device;
That causes a network device to execute.

It is a figure for demonstrating the outline | summary of embodiment of this technique. It is a figure for demonstrating the outline | summary of embodiment of this technique. It is a figure for demonstrating the outline | summary of embodiment of this technique. It is a system configuration figure concerning an embodiment. It is a functional block diagram of a network device. It is a figure which shows an example of the data stored in a resource management table. It is a figure which shows an example of the data stored in the transfer management table in 1st Embodiment. It is a figure for demonstrating the process outline | summary of 1st Embodiment. It is a figure for demonstrating the process outline | summary of 1st Embodiment. It is a figure which shows an example of the data stored in a resource management table. It is a figure which shows an example of the data stored in a resource management table. It is a figure for demonstrating the process outline | summary of 1st Embodiment. It is a figure which shows an example of the data stored in a resource management table. It is a figure for demonstrating the process outline | summary of 1st Embodiment. It is a figure for demonstrating the process outline | summary of 1st Embodiment. It is a figure which shows the processing flow of the process which acquires an operation condition and resource information. It is a figure for demonstrating the process which acquires an operation condition and resource information. It is a figure which shows the processing flow at the time of frame reception. It is a figure which shows the processing flow of the frame transfer process in 1st Embodiment. It is a figure which shows the processing flow when the free space of a buffer exceeds the 2nd threshold value after falling below the 1st threshold value. It is a figure which shows the processing flow of the frame acquisition process in 1st Embodiment. It is a figure which shows the processing flow of the other apparatus in 1st Embodiment. It is a figure which shows an example of the data stored in the transfer management table in 2nd Embodiment. It is a figure for demonstrating the process outline | summary of 2nd Embodiment. (A) And (b) is a figure showing the structure of the header in 2nd Embodiment. It is a figure for demonstrating the process outline | summary of 2nd Embodiment. It is a figure for demonstrating the process outline | summary of 2nd Embodiment. It is a figure for demonstrating the process outline | summary of 2nd Embodiment. It is a figure for demonstrating the process outline | summary of 2nd Embodiment. It is a figure for demonstrating the process outline | summary of 2nd Embodiment. It is a figure which shows the processing flow of the frame transfer process 2 in 2nd Embodiment. It is a figure which shows the processing flow of the frame acquisition process 2 in 2nd Embodiment. It is a figure which shows the processing flow of the other apparatus in 2nd Embodiment.

Explanation of symbols

1, 11 Network 3A, 3B, 3C, 3D Network device 30 Network system 301 Frame receiving unit 302 First determination processing unit 303 Frame processing unit 304 Resource management table storage unit 305 Resource management unit 306 Transfer management table storage unit 307 Frame transfer unit 308 Second determination processing unit 309 Frame acquisition unit 310 Transfer data processing unit 311 Buffer

Claims (5)

A network device,
A buffer,
Receiving means for sequentially receiving layer 2 frames;
First determination means for determining whether the free space of the buffer exceeds a first threshold;
Means for storing the received layer 2 frame in the buffer when the first determining means determines that the free capacity of the buffer exceeds the first threshold;
When the first determination means determines that the free space of the buffer is below the first threshold, the received layer 2 frame and a predetermined header different from the header of the layer 2 frame Transfer means for generating transfer data including, and transferring to another network device that is preset to temporarily store the layer 2 frame instead of the network device;
A network device. Second judging means for judging whether or not the free capacity of the buffer exceeds a second threshold after it is judged in the first judging means that the free capacity of the buffer is lower than the first threshold;
When the second determination means determines that the free space of the buffer exceeds the second threshold, the transfer data is acquired from the other network device, and the layer 2 frame included in the transfer data is stored in the layer 2 frame. Acquisition means for storing in a buffer;
The network device according to claim 1, further comprising: Means for acquiring operation status and resource information from each of the plurality of other network devices at a predetermined timing when there are a plurality of the other network devices;
The transfer means is
A unit that identifies, as a transfer destination, a device that is in operation and has the most available resources among the plurality of other network devices;
Means for storing a frame number of the layer 2 frame included in the transfer data and information indicating a transfer destination in a transfer management table;
Have
The acquisition means is
The network apparatus according to claim 2, further comprising: means for acquiring the transfer data in accordance with the frame number stored in the transfer management table and information indicating the transfer destination. An information processing method for virtualizing resources executed by a network device,
Sequentially receiving layer 2 frames;
A determination step of determining whether a free space of a buffer in the network device exceeds a first threshold;
Storing the received layer 2 frame in the buffer when it is determined in the determining step that the free space of the buffer exceeds the first threshold;
When it is determined in the determination step that the free space of the buffer is lower than the first threshold, the transfer including the received layer 2 frame and a predetermined header different from the header of the layer 2 frame Generating data and transferring it to another network device preset to temporarily store the layer 2 frame instead of the network device;
An information processing method for virtualizing resources, including: A program for causing a network device to execute processing for virtualizing resources,
Sequentially receiving layer 2 frames;
A determination step of determining whether a free space of a buffer in the network device exceeds a first threshold;
Storing the received layer 2 frame in the buffer when it is determined in the determining step that the free space of the buffer exceeds the first threshold;
When it is determined in the determination step that the free space of the buffer is lower than the first threshold, the transfer including the received layer 2 frame and a predetermined header different from the header of the layer 2 frame Generating data and transferring it to another network device preset to temporarily store the layer 2 frame instead of the network device;
That causes a network device to execute.

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