JP4294627B2 - Packet relay device - Google Patents

Description

  The present invention relates to a packet relay apparatus that performs bandwidth control when a packet is relayed via a network.

  As a device related to a conventional packet relay device, a plurality of packet receiving circuits that perform packet reception processing, a routing processing unit that performs packet routing processing, and a packet relay that switches packets to an output line specified by the routing processing A router is known that includes processing means, a shaper unit corresponding to each output line, and a packet transmission circuit that performs transmission processing on the output line (see, for example, Patent Document 1).

  Note that a traffic shaper (hereinafter simply referred to as a shaper) is, for example, a packet that is output when a plurality of packet receiving circuits simultaneously receive packets and the received packets are concentrated on one output line. When the transmission amount exceeds the bandwidth of the output line, the packet is discarded, so that the transmission amount of the output packet is controlled, that is, the packet transmission is performed so as not to exceed the bandwidth of the output line. Control the amount constant.

  By the way, in recent years, so-called streaming technology that distributes electronic content to be a moving image or sound in real time via a network has become widespread. FIG. 7 is a diagram illustrating a conventional streaming technique implemented via a shaper.

  As shown in FIG. 7A, the communication system to which the streaming technology is applied includes a server 9 that distributes content, a packet relay device 7 that relays packets including content data constituting the content, and a server 9. A communication terminal 6 that receives the distributed packet via the network 5 is provided.

  The packet relay device 7 has the shaper 8 described above, and the shaper 8 controls the packet transmission amount distributed from the server 9 to be constant as shown in FIG. Relays the packet controlled by the shaper 8 to the communication terminal 6.

  Further, the communication terminal 6 in which the software for reproducing the content is installed receives the packet relayed from the packet relay device 7 via the network 5 and is included in the received packet as shown in FIG. The content data to be stored is accumulated in the buffer until a certain amount is reached, and when the content data accumulated in the buffer reaches a certain amount, the reproduction of the content data is started.

Accordingly, even if the content data included in the distributed packet may not be temporarily transferred for some reason, the communication terminal 6 can reproduce the content data stored in the buffer. And users can view the sound without problems. Note that the reproduced content data is erased from the buffer.
JP 2001-326688 A (page 9, FIG. 1)

  However, even if the server 9 delivers a large amount of packets to the communication terminal 6, the conventional packet relay device 7 described above is transferred to the communication terminal 6 by the shaper 8 controlling the packet transmission amount to be constant. Since the amount of packet transmission becomes constant and the content data does not reach a certain amount immediately, there is a problem that the start of content reproduction is delayed and the user waits for content viewing.

  The present invention has been made to solve the conventional problems, and an object of the present invention is to provide a packet relay device that can provide a comfortable viewing to the user without waiting for the content to be viewed.

The packet relay device of the present invention receives an input unit (11) to which a packet is input, an output unit (12) for outputting the packet to a transmission path, and a packet input to the input unit, And a bandwidth control unit (13) that performs bandwidth control on the transmission path, and in the packet relay device that performs bandwidth control of the transmission path, control for registering identification information for identifying a packet that is subject to bandwidth control in a registration table Unit (14), a flow detection unit (15) for detecting a packet that is not a registered packet identified by the identification information registered in the registration table, and an output destination of the registered packet as the bandwidth control unit or the output unit further comprising a switching unit (16) for switching on, the control unit, the identification information when the flow detection unit detects a packet not the registration packet Registered in the registration table, the switching unit outputs the registration packet from the time when the flow detection unit detects a packet not the registration packet until a predetermined time elapses to the output unit, the previous Kisho constant time When the time has elapsed, the registration packet is switched from the output unit to the bandwidth control unit and output.
With this configuration, while the switching unit outputs the packet transmitted from the server to the output unit, a large number of packets are transferred from the packet relay device to the communication terminal at a time, so the packets relayed from the packet relay device Can be shortened from the time when the communication terminal that receives the data via the network starts to accumulate the content data contained in the received packet to the time when the content data reaches a certain amount, and immediately starts playing the content data. Thus, comfortable viewing can be provided to the user without waiting for the content to be viewed.

Further, the packet relay device of the present invention has a configuration in which the control unit cancels identification information for identifying the registration packet from the registration table when the registration packet is not input from the input unit for a certain period of time. ing.
With this configuration, when the registration packet is not input for a certain period of time, the identification information for identifying the registration packet is released from the registration table. Therefore, when the content distribution is finished, the bandwidth control of the registration packet is surely terminated. can do.

The packet relay apparatus of the present invention has a configuration in which the predetermined time is variable according to the registration packet.
With this configuration, the output destination of the registration packet can be switched from the bandwidth control unit to the output unit in accordance with the timing at which the communication terminal starts playback according to the characteristics of the content distributed from the server.

The packet relay apparatus of the present invention further includes a priority bandwidth control unit (28) that performs bandwidth control on a packet that is input to the input unit in a bandwidth that is greater than a bandwidth that is to be controlled by the bandwidth control unit, switching unit, instead of outputting the registration packet to said flow detection unit a predetermined time from the time of detecting the packet non the registration packet has passed to the output unit, and outputs the priority bandwidth control unit, before Kisho When a predetermined time elapses , the registration packet is switched from the priority bandwidth controller to the bandwidth controller and output.
With this configuration, while the switching unit outputs the packet transmitted from the server to the output unit, a large number of packets are transferred from the packet relay device to the communication terminal at a time, so the packets relayed from the packet relay device The time from when the communication terminal that receives the content data starts to accumulate the content data contained in the received packet to the time when the content data reaches a certain amount can be shortened, and playback of the content data starts immediately Thus, comfortable viewing can be provided to the user without waiting for the content to be viewed.

  The present invention provides a packet relay device that can provide a comfortable viewing to a user without waiting for the content to be viewed.

  Hereinafter, a packet relay device according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a configuration diagram of a communication system according to an embodiment of the present invention. As shown in FIG. 1, the communication system according to the embodiment of the present invention includes a server 9A, 9B that distributes electronic content that becomes a moving image or sound, and a packet that relays a packet that includes content data constituting the content. A relay device 10 and a communication terminal 6 that receives packets distributed from the servers 9A and 9B via the network 5 are provided.

  In addition, when not distinguishing each of server 9A, 9B, it demonstrates as the server 9. FIG. Although two servers 9A and 9B are illustrated as the server 9, the number of servers 9 is not particularly limited.

  Note that software for reproducing content is installed in the communication terminal 6, and the communication terminal 6 receives a packet that is streamed and distributed from the server 9, and receives a certain amount of content data contained in the received packet. The content data is accumulated in the buffer until the time reaches, and when the content data accumulated in the buffer reaches a certain amount, the reproduction of the content data is started.

  Further, in the communication system according to the embodiment of the present invention, when there are a plurality of communication terminals 6, the packet relay device 10 relays the content distributed from the server 9 to each communication terminal 6. ing.

  FIG. 2 shows a configuration diagram of the packet relay apparatus according to the embodiment of the present invention. As illustrated in FIG. 2, the packet relay device 10 includes an input unit 11, an output unit 12, a bandwidth control unit 13, a switching unit 16, a control unit 14, a flow detection unit 15, and a timer 17.

  The input unit 11 and the output unit 12 are constituted by a network interface, for example. The input unit 11 outputs the input packet to the flow detection unit 15. The output unit 12 is configured to output the packet input from the bandwidth control unit 13 or the switching unit 16 to the transmission path.

  The input / output packet is, for example, a packet corresponding to the Internet protocol (hereinafter referred to as an IP packet), and the IP packet includes a header portion and a payload portion. The header part includes a destination address and a source address. The payload portion includes data that conforms to a protocol such as TCP or UDP.

  The bandwidth control unit 13 is formed of a shaper, for example, and performs bandwidth control on a packet input from the input unit 11.

  The control unit 14 includes, for example, a processor and a memory, and registers identification information for identifying a packet subjected to bandwidth control in the registration table. Note that a packet to be subjected to bandwidth control is determined in advance by designation by a network administrator.

  For example, when the packet is an IP packet, the information constituting the identification information includes at least one of a destination address and a transmission source address, and may further include a TCP or UDP port number.

  An example of the registration table is shown in FIG. The registration table shown in FIG. 3A includes identification information, switching status corresponding to the identification information, switching count value, release count value, count increment value, and the like. Details of these pieces of information will be described later.

  When the flow detection unit 15 outputs the input packet to the switching unit 16, the flow detection unit 15 detects a packet that is not a registered packet identified by the identification information registered in the registration table from among the packets subjected to bandwidth control. It is like that.

  In FIG. 2, the switching unit 16 switches the output destination of the registration packet to the bandwidth control unit 13 or the output unit 12. Therefore, when the switching unit 16 outputs the registration packet to the output unit 12, the registration packet is output to the transmission path by the output unit 12 without being controlled by the bandwidth control unit 13, and the switching unit 16 transmits the registration packet. When output to the bandwidth control unit 13, the registration packet is output to the transmission path by the output unit 12 under the control of the bandwidth control unit 13.

  The timer 17 notifies the control unit 14 of the passage of time at regular intervals. When the timer 17 notifies the passage of time, the control unit 14 adds the count increment value to the switching count value, and the switching unit 16 switches the output destination of the registration packet according to the integrated switching count value. The timing is detected, and the control unit 14 adds a fixed value to the release count value, and releases the identification information registered from the registration table according to the added release count value.

  The operation of the packet relay apparatus according to the embodiment of the present invention configured as described above will be described below with reference to the drawings. Further, in the embodiment of the present invention, in order to facilitate understanding of the present invention, the packets subjected to bandwidth control are IP packets transmitted from the servers 9A and 9B, and the source address A and the source address B, respectively. As an IP packet having

  First, when nothing is registered in the registration table, for example, when an IP packet having a source address A is input, the flow detection unit 15 outputs the input IP packet to the switching unit 16. In addition, referring to the registration table, since nothing is registered in the registration table, the IP packet having the source address A is detected as a packet that is not a registration packet.

  The control unit 14 registers the source address A, which is identification information of the IP packet when the flow detection unit 15 detects, in the registration table as shown in FIG. 3B, and at the same time, the switching state corresponding to this identification information. Is initialized to “output unit 12”, the switching count value and the cancellation count value are initialized to 0, and the count increment value is initialized to a value corresponding to the source address.

  The control unit 14 registers the transmission source address A in the registration table, and the switching unit 16 corresponds to the transmission source address A from the registration table every time an IP packet having the transmission source address A is input from the flow detection unit 15. Since the switching state indicates the output unit 12, the registration packet having the transmission source address A is sequentially output to the output unit 12. Instead of referring to the switching state, the switching unit 16 may receive the switching state of the IP packet together with the IP packet from the flow detection unit 15 and output a registration packet according to the received switching state.

  While the registration packet having the transmission source address A is sequentially output to the output unit 12, the timer 17 notifies the elapse of time, and the control unit 14 adds the count increment value to the switching count value, and releases the count value. A certain value is added to.

  Note that each time the switching unit 16 receives an IP packet having the transmission source address A from the flow detection unit 15, the release count value is initialized. Further, when the flow detection unit 15 detects a registration packet, the release count value may be initialized.

  If the cancellation count value is not initialized, the cancellation count value is accumulated and eventually becomes a value representing a certain time, and the control unit 14 cancels the transmission source address A, which is identification information for identifying the registration packet, from the registration table. To do.

  On the other hand, the switching count value is integrated and eventually becomes a value representing a predetermined time, the control unit 14 sets the switching state corresponding to the transmission source address A to “bandwidth control unit 13”, and the switching unit 16 sets the transmission source address A to Each time an IP packet is input from the flow detection unit 15, the switching state corresponding to the transmission source address A is referred to from the registration table, and the switching state indicates the bandwidth control unit 13. The registration packets having the original address A are sequentially output.

  As shown in FIG. 4A, while the switching unit 16 outputs the IP packet transmitted from the server 9A to the output unit 12, a large amount of IP packets are sent from the packet relay device 10 to the communication terminal 6 at once. Transferred. In addition, while the switching unit 16 outputs the IP packet to the bandwidth control unit 13, the bandwidth control unit 13 controls the transmission amount of the IP packet to be constant. The data is transferred from the device 10 to the communication terminal 6.

  In addition, the communication terminal 6 receives the IP packet relayed from the packet relay device 7 via the network 5, and starts accumulation of content data included in the received IP packet as shown in FIG. 4B. Since the time from the time point to the time point when the content data reaches a certain amount is short, the reproduction of the content data can be started immediately. Accordingly, comfortable viewing can be provided to the user without waiting for the content to be viewed.

  Note that while the transmission source address A is registered in the registration table, the flow detection unit 15 inputs an IP packet having the transmission source address B and outputs the IP packet having the transmission source address B to the switching unit 16. At this time, referring to the registration table, since the transmission source address B is not registered in the registration table, an IP packet having the transmission source address B is detected as a packet that is not a registration packet. The control unit 14 registers the transmission source address B, which is identification information of the IP packet when the flow detection unit 15 detects, in the registration table as shown in FIG. 3C, and at the same time, the switching state corresponding to this identification information. Is set to “output unit 12”, and the switching count value, the release count value, and the count increment value are initialized.

  Further, as shown in FIG. 3C, the control unit 14 changes the count increment value according to the contents of the identification information, so that the switching unit 16 switches the output destination of the registration packet according to the registration packet. The predetermined time can be made variable. Therefore, since the timing at which the communication terminal 6 starts playback differs according to the characteristics of the content distributed from the server 9A and the content distributed from the server 9B, the registration packet The output destination can be switched from the band control unit 13 to the output unit 12.

  In addition, although the form which accumulate | stores switching count value and cancellation | release count value was demonstrated, when initializing each value, the control part 14 sets a predetermined constant and when the timer 17 notifies progress of time. Alternatively, it may be subtracted from the set predetermined constant. In the subtraction, when the switching count value or the cancellation count value becomes 0, the timing for switching the output destination of the registration packet and the timing for canceling the registered identification information from the registration table are detected.

  A modification of the packet relay device 10 described in FIG. 2 is shown in FIG. As shown in FIG. 5, the packet relay device 20 has a configuration in which a priority bandwidth control unit 28 that preferentially controls bandwidth for the IP packet input to the input unit 11 is added to the components of the packet relay device 10. have. Note that the priority band control unit 28 is formed of, for example, a shaper, and the IP packet controlled by the priority band control unit 28 is transmitted via the output unit 12 with a larger band (higher rate) than that controlled by the band control unit 13. Is output.

  As an operation of the modified example of the packet relay device according to the embodiment of the present invention, first, in the case where nothing is registered in the registration table, the flow detection unit 15 selects, for example, an IP packet having the source address A. When the input IP packet is input and output to the switching unit 16, the registration table is referred to, and nothing is registered in the registration table. To detect.

  The control unit 14 registers the source address A, which is identification information of the IP packet when the flow detection unit 15 detects, in the registration table as shown in FIG. 6A, and at the same time, the switching state corresponding to this identification information. Is set as the “priority bandwidth control unit 28”, and the switching count value, the release count value, and the count increment value are initialized.

  The control unit 14 registers the transmission source address A in the registration table, and the switching unit 16 corresponds to the transmission source address A from the registration table every time an IP packet having the transmission source address A is input from the flow detection unit 15. Since the switching state indicates the priority band control unit 28, the registration packet having the transmission source address A is sequentially output to the output unit 12.

  On the other hand, the switching count value is integrated and eventually becomes a value representing a predetermined time, the control unit 14 sets the switching state corresponding to the transmission source address A to “bandwidth control unit 13”, and the switching unit 16 sets the transmission source address A to Each time an IP packet is input from the flow detection unit 15, the switching state corresponding to the source address A is referred to from the registration table, and the switching state indicates the bandwidth control unit 13. The registration packets having the original address A are sequentially output.

  As shown in FIG. 6B, while the switching unit 16 outputs the IP packet transmitted from the server 9A to the priority bandwidth control unit 28, the IP packet is transmitted from the packet relay device 10 to the communication terminal 6 at a short interval. Since the bandwidth control unit 13 controls the transmission amount of the IP packet to be constant while the switching unit 16 outputs to the bandwidth control unit 13, the IP packet is transmitted to the packet relay device with the transmission amount constant. 10 to the communication terminal 6.

  In addition, the communication terminal 6 receives the IP packet relayed from the packet relay device 7 via the network 5 and starts storing content data included in the received IP packet as shown in FIG. 6C. Since the time from the time point to the time point when the content data reaches a certain amount is short, the reproduction of the content data can be started immediately.

  As described above, the packet relay apparatus according to the present invention has an effect that it can provide a comfortable viewing to the user without waiting for the content to be viewed, and when the packet is relayed via the network. It is useful as a router, shaper, or switch for performing bandwidth control.

Configuration diagram of a communication system according to an embodiment of the present invention Configuration diagram of a packet relay device according to an embodiment of the present invention Figure showing an example of a registration table Explanatory drawing which concerns on the flow of the packet which the packet relay apparatus and communication terminal which concern on embodiment of this invention process The figure which shows the modification of the packet relay apparatus which concerns on embodiment of this invention Operation explanatory diagram according to a modification of the packet relay device according to the embodiment of the present invention Operation explanatory diagram of a conventional packet relay device

Explanation of symbols

DESCRIPTION OF SYMBOLS 5 Network 6 Communication terminal 7, 10, 20 Packet relay apparatus 8 Shaper 9, 9A, 9B Server 11 Input part 12 Output part 13 Band control part 14 Control part 15 Flow detection part 16 Switching part 17 Timer 28 Priority band control part

Claims (4)

An input unit (11) to which a packet is input;
An output unit (12) for outputting the packet to a transmission line;
In the packet relay device comprising a bandwidth control unit (13) that receives the packet input to the input unit and performs bandwidth control on the packet, and performs bandwidth control of the transmission path ,
A control unit (14) for registering identification information for identifying a packet to be subjected to the bandwidth control in a registration table;
A flow detector (15) for detecting a packet that is not a registered packet identified by the identification information registered in the registration table;
Further comprising a switching unit (16) for switching the output destination of the registration packet to the bandwidth control section or the output section,
Wherein the control unit registers the identification information when the flow detection unit detects a packet not the registration packet to the registration table,
The switching unit, the registration packet from the time when the flow detection unit detects a packet not the registration packet until a predetermined time elapses and outputs to the output unit, when the front Kisho constant time has elapsed, the registration packet Is switched from the output unit to the bandwidth control unit and output.   2. The packet relay device according to claim 1, wherein the control unit cancels identification information for identifying the registration packet from the registration table when the registration packet is not input from the input unit for a certain period of time. .   The packet relay apparatus according to claim 1, wherein the predetermined time is variable according to the registration packet. A priority bandwidth control unit (28) for performing bandwidth control on a packet input to the input unit in a bandwidth larger than a bandwidth to be controlled by the bandwidth control unit;
The switching unit, instead of outputting the registration packet to said flow detection unit a predetermined time from the time of detecting the packet non the registration packet has passed to the output unit, and outputs the priority bandwidth control unit, before Symbol when Tokoro constant time has passed, the packet relay apparatus according to claim 1, characterized in that the output switches the registration packet from the priority bandwidth control unit to the band control section to claim 3.

Images