JP3816834B2 - Network bandwidth controller - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a network relay device that relays between networks. In particular, the present invention is incorporated in the network relay device and changes the frequency band corresponding to the transmission rate of data input from one network to the other network. The present invention relates to a network bandwidth control device that transmits data to a network.
[0002]
[Prior art]
For example, as shown in FIG. 5, a network relay device 3 that relays data transmission between a LAN 1 that performs high-speed data communication on the order of G1 bps and a WAN 2 that performs low-speed data communication on the order of 200 to 300 Mbps is put into practical use. ing. In addition, each data is transmitted / received in the state incorporated in the packet on LAN1 and WAN2.
[0003]
In this network relay device 3, a transmission / reception circuit 4 for transmitting / receiving packets to / from the LAN 1 and a transmission / reception circuit 5 for transmitting / receiving packets to / from the WAN 2 are incorporated. Each of the transmission / reception circuits 4 and 5 converts the received packet into a frequency band corresponding to the transmission speed of the transmission destination, and transfers the received packet to the transmission / reception circuits 5 and 4 on the other side. To do.
[0004]
In such a network system, when various types of information are transmitted from the information providing server 6 connected to the LAN 1 to the user terminal 7 connected to the WAN 2, for example, the speed of data output from the information providing server 6 ( If the frequency band) is 1 Gbps and the speed (frequency band) of data that can be processed by the terminal 7 of the user is 200 Mbps, the network relay device that is the entrance where the speed is reduced if the transmission is continued from the information providing server 6 The data received at 3 overflows without being processed. Therefore, in the network relay device 3, when the number of packets sent to the WAN 2 within a unit time reaches a predetermined limit number of packets that can be processed by the terminal 7, the data is transmitted to the information providing server 6 of the transmission source via the LAN 1. A transmission stop command is transmitted to stop data transmission from the information providing server 6 for a predetermined time.
[0005]
[Problems to be solved by the invention]
However, the network relay device 3 shown in FIG. 5 still has the following problems to be solved.
[0006]
That is, as described above, the data transmitted on the LAN 1 and WAN 2 are each incorporated in a packet and transmitted. However, the number of data incorporated in each packet can be arbitrarily set by the designer. Therefore, the packet length of each packet is not constant. For example, the packet length of a packet output from one information providing server 6 is set to be long, and the packet length of a packet output from another information providing server 6 is set to be short.
[0007]
Thus, even if the packets whose packet length (number of data) is not constant are collected by the above-mentioned limit number of packets, the total number of data greatly fluctuates. However, the next data transmission stop time is constant. In this case, if the total number of data becomes larger than the number of data that can be processed by the user terminal 7, unprocessed data remains in the terminal 7 even after the next data transmission stop time elapses. Disappearance occurs.
[0008]
In this case, the user terminal 7 transmits a packet retransmission request to the information providing server 6. The information providing server 6 retransmits the same packet, but if the same packet is retransmitted frequently, the data transmission efficiency decreases.
[0009]
Furthermore, in the network relay device 3 shown in FIG. 5, when data is relayed from the high-speed LAN 1 to the low-speed WAN 2, the transmission speed (frequency band) is the maximum data processing capacity of each terminal 7 connected to the WAN 2. It is converted to the corresponding transmission rate (frequency band).
[0010]
Generally, when a user of each terminal 7 uses a network for a fee, it tends to be expensive if communication is performed at a high speed (wide frequency band). However, some users of each terminal 7 think that a lower price is better even at a low speed (the frequency band is narrow). The network relay device 3 in FIG. 5 cannot cope with such a request.
[0011]
The present invention has been made in view of such circumstances, and by stopping the data input by the number of stop data separately calculated every time the data sequentially input from the network reaches the specified number of data, even at high speed. Even when data is relayed from a low-speed network to a low-speed network, packet loss can be greatly suppressed, data transmission efficiency is improved, and the user can select the desired transmission speed (frequency band) An object is to provide a control device.
[0012]
[Means for Solving the Problems]
The present invention changes the frequency band of data incorporated in a packet input from the first network via the first network transmission / reception circuit and sends the data to the second network via the second network transmission / reception circuit. A network bandwidth control device.
[0013]
Furthermore, in the network bandwidth control device of the present invention, a data number counter that repeatedly counts the number of data input from the first network transmission / reception circuit until a predetermined number of data is specified, and an externally specified use A stop data number calculation unit that calculates the number of stop data with respect to the specified number of data from the frequency band and the frequency band of data input from the first network transmission / reception circuit, and every time the data number counter finishes counting the specified number of data A stop data number counter for counting the number of stop data calculated by the stop data number calculation unit, and sending data to the first network transmitting / receiving circuit during the period when the stop data number counter is counting the number of stop data A stop signal sending unit for outputting a stop signal for instructing a stop, and a first network during a stop signal output period. And a data buffer for holding data inputted from the click receiving circuit to the stop signal cancel time.
[0014]
In the network bandwidth control apparatus configured as described above, each data incorporated in a packet input from the first network via the first network transmission / reception circuit has the frame of each packet removed by a data number counter. Counting is repeated until the specified number of data is reached. Further, the number of stop data with respect to the specified number of data is calculated from the use frequency band designated from the outside and the frequency band of the data input from the first network transmission / reception circuit. More specifically, when the specified number of data is input via the first network transmission / reception circuit, the number of data when the data input is maintained in the stop state is the stop data number.
[0015]
Therefore, for example, a user of a terminal connected to a low-speed network can specify a low-speed transmission speed (frequency band) other than a high-speed transmission speed (frequency band) corresponding to the maximum data processing capability of the terminal. .
[0016]
When calculating the number of stop data with respect to the specified number of data, if the user specifies a use frequency band that is half the frequency band of the data output from the first network transmission / reception circuit, the number of stop data is equal to the specified number of data. When the user designates a use frequency band that is the same as the frequency band of data output from the first network transmission / reception circuit, the number of stop data is zero.
[0017]
The stop data number counter starts counting the calculated stop data number every time the specified data number is counted by the data number counter. A stop signal is transmitted to the first network transmission / reception circuit during a period of counting the stop data number. Therefore, no data is input to the second network transmission / reception circuit during the output period of the stop signal.
[0018]
The number of stop data is determined by the use frequency band designated by the user, the frequency band of the data output from the first network transmission / reception circuit and the specified number of data as described above, and the number of data of data incorporated in the packet Does not depend on anything. Therefore, in the terminal connected to the second network that has received the data, it is possible to prevent unprocessed data from remaining in the terminal even after the data reception stop period has elapsed, and to suppress the disappearance of the packet.
[0019]
In another aspect of the invention, the stop data number counter in the network bandwidth control apparatus of the invention described above is based on the clock of the data reception clock signal transmitted from the second network transmission / reception circuit to the first network transmission / reception circuit. Count the number.
[0020]
In yet another network bandwidth control apparatus according to the present invention, transmission of the data reception clock signal is stopped during a period in which a data transmission stop request is input from the second network to the second network transmission / reception circuit.
[0021]
In the network bandwidth control device configured as described above, for example, when a data processing load increases in a terminal connected to the second network and a data transmission stop request is output from the terminal, the data transmission stop request During the output period, transmission of the data reception clock signal is stopped.
[0022]
As a result, since the count value of the stop data number counter does not advance during this transmission stop period, the stop signal for the first network transmission / reception circuit maintains the output state. Therefore, data is not output from the first network transmission / reception circuit during the data transmission stop request output period from the terminal.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a schematic configuration of a network system in which a network bandwidth control apparatus according to an embodiment of the present invention is incorporated. The same parts as those of the conventional network system shown in FIG.
[0024]
For example, a network relay device that relays data transmission between a LAN 1 as a first network that performs high-speed data communication in the order of Gbps and a WAN 2 as a second network that performs low-speed data communication in the order of 200 to 300 Mbps. 8 is connected. An information providing server 6 that provides various types of information is connected to the LAN 1, and a user terminal 7 is connected to the WAN 2. As shown in FIG. 3, each data is transmitted and received on the LANL1 and WAN2 in a state of being incorporated in a packet. That is, in each successive packet 12, a plurality of data 13 is incorporated between the start flag at the beginning and the end flag at the end. The start flag, end flag, and each data are each formed by 8 bits. The packet length of the packet 12 is a value obtained by adding the start flag and end flag at both ends to the number of data. In this embodiment, both the start flag and the end flag are regarded as one piece of data 13.
[0025]
In the network relay device 8, a transmission / reception circuit 9 as a first network transmission / reception circuit for transmitting / receiving each data 13 incorporated in the packet 12 to the LAN 1, and each incorporated in the packet 12 to the WAN 2. A transmission / reception circuit 10 as a second network transmission / reception circuit for transmitting / receiving data 13 and a network band control device 11 are incorporated.
[0026]
The transmission / reception circuit 9 for the LAN 1 converts the transmission speed (frequency band) of, for example, 1 Gbps (Hz) of the packet 12 in which each received data 13 is incorporated into a transmission speed (frequency band) of 622 Mbps (Hz) to control the network band. Send to device 11.
[0027]
The transmission / reception circuit 10 for the WAN 2 transmits, via the WAN 2, each packet 12 in which each data 13 into which the transmission rate (frequency band) received from the network band control device 11 is converted into the designated transmission rate (frequency band) is incorporated. It transmits to the terminal 7 of the user.
[0028]
A data signal a in which each data 13 constituting the packet 12 shown in FIG. 2 input from the transmission / reception circuit 9 continues is sent to the data number counter 14 and the data buffer 15.
[0029]
Further, as shown in FIGS. 2 and 3, the transmission / reception circuit 10 connected to the WAN 2 receives a data reception clock signal for receiving each data 13 of the data signal a output from the transmission / reception circuit 9 connected to the LAN 1. c is transmitted to the transmission / reception circuit 9. Therefore, the clock cycle of the data reception clock signal c is equal to the transmission cycle of each data 13 of the data signal a output from the transmission / reception circuit 9. The data reception clock signal c is sent to the stop data number counter 16 in addition to the transmission / reception circuit 9.
[0030]
The user terminal 7 connected to the WAN 2 switches the WAN 2 when the data processing for each data 13 incorporated in each packet 12 of the data signal g supplied from the transmission / reception circuit 10 via the WAN 2 is delayed. Then, a data transmission stop request signal b is sent to the transmission / reception circuit 10. The transmission / reception circuit 10 interrupts transmission of the data reception clock signal c to the transmission / reception circuit 9 during the period T _S during which the data transmission stop request signal b is input.
[0031]
The data number counter 14 counts each data 13 of the packet 12 included in the input data signal a in a state where the framework of each packet 12 is removed, and the count value (number of data) is defined to be 128, for example. When the data number M (= 128) is reached, the count-up signal d is sent to the stop data number counter 16 and the stop signal output unit 17 as shown in FIG. Thereafter, the count value (data number) is reset, and the count of the data number is restarted.
[0032]
A set value α of the used frequency frequency band (used transmission rate) desired by the user of the terminal 7 is input from the used band setting unit 19 to the stop data number calculating unit 18. As shown in FIG. 4, the set value α of the used frequency band is shown as a ratio with respect to the transmission rate B (= 622 Mbps) of the data signal a input from the transmission / reception circuit 9 to the network band control device 11. . For example, when the use frequency frequency band is equal to the transmission speed B of the data signal a, the set value α is 1. When the use frequency frequency band is half of the transmission speed B of the data signal a, the set value α is 0.5. It is.
[0033]
Then, the stop data number calculation unit 18 uses the set value α of the used frequency band and the above-described specified data number M (= 128) by the following formula, and the stop data number C with respect to the specified data number M (= 128). _R is calculated.
[0034]
C _R = M (1−α) / α
According to this equation, as shown in FIG. 4, when the used frequency band (used transmission rate) is equal to the transmission rate B of the data signal a, the set value α is 1 and the number of stopped data _CR is 0. . When the use frequency band (use transmission speed) is half of the transmission speed B of the data signal a, the set value α is 0.5, and the stop data number _CR is equal to the specified data number M. Furthermore, when the use frequency frequency band (used transmission rate) is 1/3 of the transmission rate B of the data signals a, setpoint α is 0.33, stop data number C _R is twice the prescribed number of data M Become.
Stop data number calculation unit 18 sets the stop data number C _R for the calculated specified number of data M (= 128) to stop the data counter 16.
[0035]
As shown in FIG. 2, when the count-up signal d for the specified data number M (= 128) is input from the data number counter 14, the stop signal output unit 17 transmits a high (H) level stop signal f to the transmission / reception circuit. 9 and transmission to the data buffer 15.
[0036]
At the same time, as shown in FIG. 2, when the count-up signal d corresponding to the prescribed data number M (= 128) is input from the data number counter 14, the stop data number counter 16 receives the number of clocks of the data reception clock signal c, that is, Start counting the number of stop data. Then, the stop data number counter 16 sends the signal e to the stop signal output unit 17 during the counting period of high (H) level. Further, stopping the data counter 16, the count value of the clock reaches the stop data number C _R, to release the counting period in the signal e to the low (L) level, clears the count value of the clock to zero.
[0037]
As shown in FIG. 2, the stop signal output unit 17 outputs a high (H) level stop signal sent to the transmission / reception circuit 9 and the data buffer 15 when the signal e is released to the low (L) level during the counting period. Release f to low (L) level. That is, the stop data number counter 16, is output only stop signal f period that counts the stop data number C _R.
[0038]
Reception circuit 9, high (H) level period stop signal f is input, i.e., a period corresponding to the stop data number C _R stops sending the data 13. When the stop signal f is released to the low (L) level, the transmission of the data 13 is resumed. The transmission / reception circuit 9 sends a transmission stop request for the packet 12 to the information providing server 6 that is the transmission source of the packet 12 via the LAN 1 while the transmission of the data 13 is stopped.
[0039]
Since the stop signal f is output once every time the data 13 with the specified number of data M (= 128) is input, the data signal a output from the transmission / reception circuit 9 is the data with the specified number of data M (= 128). 13 is output continuously, then the output for a period corresponding to the stop data number C _R is stopped, then the M (= 128) signal form the pieces of data 13 is continuously output.
[0040]
Each data 13 of the data signal a output from the transmission / reception circuit 9 is delayed by one data time in the data buffer 15 made of, for example, a FIFO memory, and then the other transmission / reception as a new data signal g as shown in FIG. Input to the circuit 10.
[0041]
In detail, since the stop signal f rises to the high (H) level after detecting the specified data number M (= 128) th data 13, only the next data (next head data) 13 to be stopped is obtained. The data is output and input to the data buffer 15. The next head data 13 input to the data buffer 15 should be delayed by one data time and then sent to the other transmission / reception circuit 10. When the data is delayed by one data time, the data buffer 15 Since the high (H) level stop signal f is applied to this, the next head data 13 is stored and held in the data buffer 15, and when the stop signal f is set to the low (L) level, the subsequent data 13 is input to the other transmission / reception circuit 10 as a new data signal g.
[0042]
The transmission / reception circuit 10 sends a data signal g having a designated use frequency frequency band (use transmission speed) input from the other transmission / reception circuit 9 via the data buffer 15 to the user terminal 7 via the WAN 2. . The user terminal 7 receives and processes the data 13 of each packet 12 included in the data signal a having the use frequency frequency band (use transmission speed) designated by the user terminal 7.
[0043]
As shown in FIG. 2, the data reception clock signal c is not transmitted to the transmission / reception circuit 9 as described above during the period T _S in which the user terminal 7 outputs the data transmission stop signal b. As a result, in this transmission stop period T _S , the count value of the stop data number counter 16 does not advance, so that the stop signal f for the transmission / reception circuit 9 maintains the high (H) level output state. Therefore, the data 13 is not output from the transmission / reception circuit 9 during the period of the data transmission stop request output signal b from the terminal 7. Therefore, the data 13 from the transmission / reception circuit 10 is not input to the terminal 7 via the WAN 2.
[0044]
In the network bandwidth control device 11 configured as described above, the stop data number calculation unit 18 uses the set value α of the used frequency band designated by the user of the terminal 7 connected to the WAN 2, and the transmission / reception circuit 9. The stop data number C _R for the specified data number M (= 128) is calculated from the frequency band of the input data.
[0045]
In this way, the user of the terminal 7 can arbitrarily specify the use frequency band (transmission speed). Therefore, for example, the user of the terminal 7 connected to the low-speed WAN 2 designates a low-speed transmission rate (frequency band) other than the high-speed transmission rate (frequency band) corresponding to the maximum data processing capability of the terminal 7 of its own. it can. As a result, the network usage fee can be selected according to the transmission speed (frequency band).
[0046]
The calculated stop data number C _R is sent to the stop data number counter 16. The stop data number counter 16 starts counting a new specified data number M (= 128) every time counting of the specified data number M (= 128) ends. During the counting period, the stop signal f is transmitted to the transmission / reception circuit 9. Therefore, data 13 is not input to the transmission / reception circuit 10 during the output period of the stop signal f.
[0047]
Here, the stop data number C _R is determined by the use frequency band designated by the user, the frequency band of the data output from the transmission / reception circuit 9, and the specified data number M, and is the number of data 13 data incorporated in the packet 12. Is completely independent.
[0048]
Therefore, once the frequency band to be used is designated based on an instruction from the user of the terminal 7 connected to the WAN ₂ , the ratio (M / C _R ) between the specified data number M and the stopped data number C _R does not change. in terminal 7 data 13 is connected to the WAN2 which receives each packet 12 built, that unprocessed data remains in the terminal 7 even after the data reception stop period corresponding to the stop data number C _R This prevents the packet 12 from disappearing. As a result, the frequency of retransmission of the packet 12 is reduced, and the data transmission efficiency is improved.
[0049]
In addition, this invention is not limited to embodiment mentioned above. The stop data number counter 16 that counts the stop data number CR in the embodiment counts the stop data number CR by counting the clock of the data reception clock signal c. For example, the stop data number counter 16 is a clock oscillator built in itself. The clocks of the generated clock signal may be counted.
[0050]
【The invention's effect】
As described above, in the network bandwidth control device of the present invention, the input of data is stopped by the number of stop data separately calculated every time the data sequentially input from the network reaches the specified number of data.
[0051]
Therefore, even when data is relayed from a high-speed network to a low-speed network, packet loss can be greatly suppressed, data transmission efficiency is improved, and the transmission speed (frequency band) desired by the user Can be selected.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of a network system in which a network bandwidth control device according to an embodiment of the present invention is incorporated. FIG. 2 is a time chart showing the operation of the network bandwidth control device of the embodiment. FIG. 4 is a diagram showing a frame configuration of a packet input / output to / from the network bandwidth control apparatus according to the embodiment. FIG. 4 is a diagram for explaining a method for calculating the number of stop data in the network bandwidth control apparatus according to the embodiment. Block diagram showing schematic configuration of a conventional network system [Explanation of symbols]
1 ... LAN
2 ... WAN
6 ... Information providing server 7 ... Terminal 8 ... Network relay device 9, 10 ... Transmission / reception circuit 11 ... Network bandwidth control device 12 ... Packet 13 ... Data 14 ... Data number counter 15 ... Data buffer 16 ... Stop data number counter 17 ... Stop signal Sending unit 18 ... Stop data number calculating unit 19 ... Bandwidth setting unit

Claims (3)

By changing the frequency band of the data (13) incorporated in the packet (12) input from the first network (1) through the first network transmission / reception circuit (9), the second network transmission / reception circuit (10 ) Via the network bandwidth control device (11) for sending to the second network (2) via
A data number counter (14) that repeatedly counts the number of data input from the first network transmission / reception circuit until a predetermined number of specified data is reached;
A stop data number calculation unit (18) that calculates the number of stop data for the specified number of data from an externally used frequency band and a frequency band of data input from the first network transmission / reception circuit;
A stop data number counter (16) that counts the number of stop data calculated by the stop data number calculation unit each time the data number counter finishes counting the specified data number;
A stop signal sending unit (17) for outputting a stop signal for instructing the first network transmitting / receiving circuit to stop sending data during a period in which the stop data number counter is counting the number of stop data;
A network bandwidth control device comprising: a data buffer (15) for holding data input from the first network reception circuit during a stop signal output period until a stop signal release time. 2. The stop data number counter counts the stop data number based on a clock of a data reception clock signal transmitted from the second network transmission / reception circuit to the first network transmission / reception circuit. The network bandwidth control device described. 3. The network bandwidth control apparatus according to claim 2, wherein the data reception clock signal is stopped during a period in which a data transmission stop request is input from the second network to the second network transmission / reception circuit.

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