JP2011135443A - System, device, method and program for packet transfer - Google Patents

Abstract

An object of the present invention is to forcibly cut a flow accurately with one type of marking.
An ingress packet transfer apparatus and a relay packet transfer apparatus include a first token bucket process in which a forced disconnection rate is a token replenishment rate, and a predetermined constant multiple of the forced disconnection rate is a token replenishment rate. When the token amount in the first token bucket exceeds a predetermined threshold value, marking is not performed, and the token amount in the first token bucket is equal to or less than the predetermined threshold value. If it is, marking is performed in accordance with the second token bucket processing, and the egress packet transfer apparatus is based on the mark ratio of the packet transmitted from the ingress packet transfer apparatus, the reception rate, and the constant. The inbound packet transfer apparatus calculates the rate after disconnection based on the calculated rate after disconnection. To cut the over.
[Selection] Figure 1

Description

  The present invention relates to a technique for cutting an excessive flow with respect to congestion caused by a route change due to a failure of a device or the like in real-time communication including at least a telephone in an IP network.

  When real-time communication is performed in an IP (Internet Protocol) network, if a flow flowing into the network is excessively received, packet loss, delay, delay fluctuation, or the like may occur in the service flow. This packet loss, delay, delay fluctuation, etc. do not concentrate on a specific flow, but occur almost uniformly in all flows in the network, so the quality of all flows deteriorates and eventually all flows Is no longer a service. For this reason, in order to realize real-time communication, it is necessary to regulate the inflow of new flows according to the congestion status of the network. The control for restricting the flow inflow is referred to as flow acceptance control. Here, there is a case where the quality of the accepted flow cannot be ensured only by such flow acceptance control. In the IP network, when a failure or the like occurs, route switching automatically occurs. When this route switching occurs, a large amount of flow flows into a certain link. This cannot be controlled by reception control. Therefore, in order to ensure the quality of accepted flows, in addition to acceptance control, forcible disconnection is necessary for some flows.

  For example, consider an IP network in which a caller terminal 1100-1 and a callee terminal 1100-2 perform real-time communication as shown in FIG. Here, when a failure occurs in the line between the relay packet transfer device 1200-1 and the relay packet transfer device 1200-3, route switching is performed and the boundary packet transfer device 1300-1 on the entrance side and the boundary on the exit side are switched. The route to the packet transfer apparatus 1300-3 is switched as shown in FIG. That is, the flow between the relay packet transfer apparatus 1200-1 and the relay packet transfer apparatus 1200-3 is connected via the relay packet transfer apparatus 1200-2. As a result, a large amount of admission-controlled flows may flow between the relay packet transfer device 1200-2 and the relay packet transfer device 1200-3, resulting in congestion. In this case, the quality of all flows passing through the congestion occurrence link may deteriorate, and real-time communication may not be established. In order to prevent such a situation, it is necessary to ensure the quality of the remaining flow by cutting a part of the flow.

  Here, the IETF (Internet Engineering Task Force) PCN WG (Congestion and Pre-Congestion Notification Working Group) ensures QoS (Quality of Service) for real-time communication that detects and notifies congestion in advance by marking packets. PCN, which is a technology, has been discussed (for example, see Non-Patent Document 1). In the PCN, two rate threshold values (admission control rate (AR: admissible rate), forced disconnection rate (SR)) are provided for each link between packet transfer apparatuses, and the traffic rate that actually flows is each rate threshold value. The packet is marked when it exceeds the limit, and the mark is totaled for each pair of the ingress and egress packet transfer devices to perform admission control and forced disconnection. The traffic rate in each link is classified into three regions based on these two rate thresholds, and communication is controlled for each region. In a region where the traffic rate is lower than the admission control rate, a new flow is accepted. In a region where the traffic rate is higher than the admission control rate and lower than the forced disconnection rate, the new flow is rejected. In an area where the traffic rate is higher than the forced disconnection rate, the acceptance of the new flow is rejected and at the same time the forcibly disconnected flow is performed. In this way, each link is divided into three areas based on the two rate thresholds, and the area to which the rate of each link belongs is determined by the mark to control communication.

  Non-Patent Document 1 discloses a technique for discriminating these three regions by one type of marking. Here, one type of marking is performed when the acceptance control rate is exceeded, and marking according to the forced cutting rate is not performed. Therefore, based on the mark information for admission control, it is estimated whether the actual traffic rate has exceeded the forced disconnection rate. In this method, excess traffic marking is used as marking for admission control. The excess rate marking is a marking method defined by Non-Patent Document 2. Excess rate marking is a method of marking incoming packets when tokens are replenished at a certain rate and there are no more tokens in the token bucket (less than the maximum packet size). The purpose of this marking method is to mark only when the traffic exceeds the token replenishment rate.

  Each packet transfer device in Non-Patent Document 1 has such a marking function, and performs marking by an excess rate marking method when the reception control rate is exceeded. The egress packet transfer apparatus calculates the mark ratio of the received packet for each ingress packet transfer apparatus by the exponential weighted moving average (EWMA), and when the value is not 0, marking is performed at regular intervals. Measure the rate that is not. This rate is transmitted to the ingress side packet transfer apparatus, and the ingress side packet transfer apparatus forcibly cuts the excess flow by using the rate multiplied by the constant U in the rate as the forcible cut rate. At this time, the constant U needs to be set to one value for the entire network. As a result, the number of markings can be reduced to one, and the functions required for the internal packet transfer apparatus can be reduced.

Charny et al., “Pre-Congestion Notification Using Single Marking for Admission and Termination”, Internet Draft: draft-charny-pcn-single-marking-03.txt, Internet Engineering Task Force, November 2007 Eardley, “Metering and marking behavior of PCN-nodes,” Internet Draft: draft-ietf-pcn-markingbehaviour-05.txt (RFC5670), Internet Engineering Task Force, August 2009.

  However, in the technique of Non-Patent Document 1, the forced disconnection rate is calculated as a constant multiple of the actual traffic rate, and since the estimation is used as to whether the actual traffic rate exceeds the forced disconnection rate threshold, the accuracy is high. There is a problem that it is low. In other words, if the flow is forcibly disconnected based on the judgment by comparing the forced disconnection rate with the actual traffic rate, it is necessary to perform the forced disconnection in the situation where the forced disconnection is not necessary or the forced disconnection is necessary. It is considered that there are cases where forced disconnection is not performed in certain situations.

  The present invention has been made in view of such a situation, and provides a packet transfer system, a packet transfer apparatus, a packet transfer method, and a packet transfer program that forcibly disconnect a flow with high accuracy by one type of marking.

  In order to solve the above-described problem, the present invention receives and transmits a packet transmitted from outside the domain that is arranged on the entrance side of the domain in a domain constituted by a plurality of packet transfer apparatuses. The packet transfer device on the ingress side that accepts the flow of real-time communication, the relay packet transfer device that receives and relays packets transmitted within the domain, and the packet that is placed on the egress side of the domain and that receives packets through the domain A packet transfer system including an egress packet transfer device that performs transfer to a first token bucket in which a predetermined forced disconnection rate is a token replenishment rate. 1st token bucket processing by, and constant predetermined for forced disconnection rate Token bucket processing unit for performing the second token bucket processing by the second token bucket with the token replenishment rate, and the token amount in the first token bucket is determined in advance according to the processing result by the token bucket processing unit. If the threshold value exceeds the threshold value, the packet is not marked. If the token amount in the first token bucket is equal to or smaller than the predetermined threshold value, the marking is performed for the packet according to the second token bucket process. And the egress packet transfer device includes a total amount of packets transmitted from the ingress packet transfer device and packets marked by the marking execution unit among packets transmitted from the ingress packet transfer device. Mark ratio, which is the ratio to the amount of packets, and packet transfer on the ingress side A packet counting unit that calculates a post-disconnection rate based on a reception rate of packets transmitted from the device and a constant, and a packet generation that transmits the post-disconnection rate calculated by the marking totaling unit to the packet transfer device on the entrance side A packet transfer device on the ingress side, and an inflow restricting unit that cuts off the accepted flow based on a post-disconnection rate transmitted from the packet transfer device on the egress side. Transfer system.

  Further, according to the present invention, the token bucket processing unit performs the reception control token bucket processing by the reception control token bucket whose predetermined reception control rate is the token replenishment rate, and the marking processing unit performs the reception control token bucket. Depending on the processing, the packet is marked once every predetermined number of times, and the packet generation unit of the egress packet transfer device accepts the packet according to the mark rate. Is sent to the ingress packet transfer device, and the inflow control unit of the ingress packet transfer device performs admission control based on the notification sent from the egress packet transfer device. It is characterized by that.

  In the present invention, when the marking execution unit inputs a packet that has already been marked and does not perform marking by itself, the number of bytes corresponding to the packet is added and stored as stock information. When it is determined that marking is performed by itself, the number of bytes corresponding to the packet is subtracted from the number of bytes indicated by the stock information, and the packet is not marked.

  In addition, the present invention accepts a flow of real-time communication by receiving a packet arranged from the outside of the domain and transmitting it within the domain in a domain constituted by a plurality of packet transfer apparatuses. Ingress packet forwarding device, relay packet forwarding device that receives and relays packets sent within the domain, and egress side packet that is placed on the domain exit side and receives packets through the domain and forwards them outside the domain A first token bucket processing by a first token bucket in which a predetermined forcible disconnection rate is a token replenishment rate, wherein the first packet bucket is an ingress packet transfer device or a relay packet transfer device in a packet transfer system comprising a transfer device; A fixed multiple of the token cutting rate A token bucket processing unit that performs a second token bucket process using a second token bucket that is a token token, and a threshold value in which a token amount in the first token bucket is determined in accordance with a processing result by the token bucket processing unit. If it exceeds, marking is not performed on the packet, and if the token amount in the first token bucket is equal to or less than a predetermined threshold, a marking execution unit that performs marking on the packet according to the second token bucket processing; It is characterized by providing.

  In addition, the present invention accepts a flow of real-time communication by receiving a packet transmitted from outside the domain that is arranged on the domain entrance side and transmitting it within the domain in a domain constituted by a plurality of packet transfer apparatuses. The first token bucket processing by the first token bucket whose predetermined forced disconnection rate is the token replenishment rate, and the second token whose predetermined multiple of the forced disconnection rate is the token replenishment rate A token bucket processing unit that performs the second token bucket processing by the bucket, and marking the packet when the token amount in the first token bucket exceeds a predetermined threshold according to the processing result by the token bucket processing unit And the token amount in the first token bucket is predetermined. If the value is equal to or smaller than the value, the ingress side packet transfer apparatus having a marking execution unit that performs marking on the packet according to the second token bucket process, and receives and relays the packet transmitted in the domain, Egress side in a packet transfer system comprising a relay packet transfer device having a bucket processing unit and a marking execution unit, and an egress packet transfer device that is arranged on the egress side of the domain and receives a packet through the domain and transfers it outside the domain Of the total number of packets transmitted from the ingress packet transfer apparatus and the amount of packets marked by the marking execution unit out of the packets transmitted from the ingress packet transfer apparatus. A certain mark ratio and the packet transmitted from the packet transfer device on the ingress side. A marking totaling unit that calculates a post-cutting rate based on a packet reception rate and a constant, and a packet generation unit that transmits the post-cutting rate calculated by the marking totaling unit to the packet transfer device on the ingress side. It is characterized by providing.

  In addition, the present invention accepts a flow of real-time communication by receiving a packet transmitted from outside the domain that is arranged on the domain entrance side and transmitting it within the domain in a domain constituted by a plurality of packet transfer apparatuses. The first token bucket processing by the first token bucket whose predetermined forced disconnection rate is the token replenishment rate, and the second token whose predetermined multiple of the forced disconnection rate is the token replenishment rate A token bucket processing unit that performs the second token bucket processing by the bucket, and marking the packet when the token amount in the first token bucket exceeds a predetermined threshold according to the processing result by the token bucket processing unit And the token amount in the first token bucket is predetermined. If the value is equal to or smaller than the value, the ingress side packet transfer apparatus having a marking execution unit that performs marking on the packet according to the second token bucket process, and receives and relays the packet transmitted in the domain, A relay packet transfer device having a bucket processing unit and a marking execution unit; and a total amount of packets transmitted from the ingress side packet transfer device that are arranged on the egress side of the domain, receive packets through the domain, transfer them outside the domain, and , A mark ratio that is a ratio of the amount of packets marked by the marking execution unit out of packets transmitted from the ingress packet transfer device, a reception rate of packets transmitted from the ingress packet transfer device, and a constant Marking totaling unit that calculates the post-cutting rate based on An ingress packet transfer apparatus in a packet transfer system comprising: an egress side packet transfer apparatus having a packet generation unit that transmits a post-disconnection rate calculated by a unit to an ingress side packet transfer apparatus; And an inflow restricting unit that cuts off the accepted flow based on the post-cut rate transmitted from the packet transfer apparatus.

  In addition, the present invention accepts a flow of real-time communication by receiving a packet arranged from the outside of the domain and transmitting it within the domain in a domain constituted by a plurality of packet transfer apparatuses. Ingress packet forwarding device, relay packet forwarding device that receives and relays packets sent within the domain, and egress side packet that is placed on the domain exit side and receives packets through the domain and forwards them outside the domain A packet transfer method for a packet transfer system including a transfer device, wherein an ingress packet transfer device and a relay packet transfer device are configured to perform a first operation using a first token bucket in which a predetermined forced disconnection rate is a token replenishment rate. Token bucket processing and the constant multiple of the predetermined disconnection rate The second token bucket processing with the second token bucket having the token replenishment rate, and if the token amount in the first token bucket exceeds a predetermined threshold, the packet is not marked, A step of marking a packet in accordance with the second token bucket processing when the token amount in one token bucket is equal to or less than a predetermined threshold, and an egress packet transfer device comprising: Mark ratio, which is the ratio of the total amount of packets transmitted from the ingress side packet transfer device to the amount of packets marked by the marking execution unit out of the packets transmitted from the ingress side packet transfer device, and the ingress side packet transfer device The rate after disconnection is calculated based on the packet reception rate and the constant. A step, a step of transmitting the post-cut rate calculated by the marking totaling unit to the packet transfer device on the ingress side, and the packet transfer device on the ingress side based on the post-cut rate transmitted from the packet transfer device on the egress side And a step of cutting the received flow.

  In addition, the present invention accepts a flow of real-time communication by receiving a packet arranged from the outside of the domain and transmitting it within the domain in a domain constituted by a plurality of packet transfer apparatuses. Ingress packet forwarding device, relay packet forwarding device that receives and relays packets sent within the domain, and egress side packet that is placed on the domain exit side and receives packets through the domain and forwards them outside the domain A first token bucket process using a first token bucket in which a predetermined forced disconnection rate is a token replenishment rate in a computer of an ingress packet transfer apparatus or a relay packet transfer apparatus in a packet transfer system including the transfer apparatus; , A predetermined constant multiple of the forced cutting rate is talk When the token amount in the first token bucket exceeds a predetermined threshold according to the step of performing the second token bucket process with the second token bucket as the replenishment rate and the processing result of the token bucket processing unit Does not perform marking on the packet, and if the token amount in the first token bucket is equal to or smaller than a predetermined threshold, performs a marking on the packet according to the second token bucket processing, and a packet for executing It is a transfer program.

  In addition, the present invention accepts a flow of real-time communication by receiving a packet transmitted from outside the domain that is arranged on the domain entrance side and transmitting it within the domain in a domain constituted by a plurality of packet transfer apparatuses. The first token bucket processing by the first token bucket whose predetermined forced disconnection rate is the token replenishment rate, and the second token whose predetermined multiple of the forced disconnection rate is the token replenishment rate A token bucket processing unit that performs the second token bucket processing by the bucket, and marking the packet when the token amount in the first token bucket exceeds a predetermined threshold according to the processing result by the token bucket processing unit And the token amount in the first token bucket is predetermined. If the value is equal to or smaller than the value, the ingress side packet transfer apparatus having a marking execution unit that performs marking on the packet according to the second token bucket process, and receives and relays the packet transmitted in the domain, Egress side in a packet transfer system comprising a relay packet transfer device having a bucket processing unit and a marking execution unit, and an egress packet transfer device that is arranged on the egress side of the domain and receives a packet through the domain and transfers it outside the domain The ratio of the total amount of packets transmitted from the packet transfer device on the ingress side to the amount of packets marked by the marking execution unit out of the packets transmitted from the packet transfer device on the ingress side Send from the packet transfer device on the entrance side with a certain mark ratio A receiving rate of packets, calculating a post-cutting rate on the basis of the constants, the calculated cut after rate, a packet transfer program for executing the steps of transmitting to the packet forwarding device of the inlet side.

  In addition, the present invention accepts a flow of real-time communication by receiving a packet transmitted from outside the domain that is arranged on the domain entrance side and transmitting it within the domain in a domain constituted by a plurality of packet transfer apparatuses. The first token bucket processing by the first token bucket whose predetermined forced disconnection rate is the token replenishment rate, and the second token whose predetermined multiple of the forced disconnection rate is the token replenishment rate A token bucket processing unit that performs the second token bucket processing by the bucket, and marking the packet when the token amount in the first token bucket exceeds a predetermined threshold according to the processing result by the token bucket processing unit And the token amount in the first token bucket is predetermined. If the value is equal to or smaller than the value, the ingress side packet transfer apparatus having a marking execution unit that performs marking on the packet according to the second token bucket process, and receives and relays the packet transmitted in the domain, A relay packet transfer device having a bucket processing unit and a marking execution unit; and a total amount of packets transmitted from the ingress side packet transfer device that are arranged on the egress side of the domain, receive packets through the domain, transfer them outside the domain, and , A mark ratio that is a ratio of the amount of packets marked by the marking execution unit out of packets transmitted from the ingress packet transfer device, a reception rate of packets transmitted from the ingress packet transfer device, and a constant Marking totaling unit that calculates the post-cutting rate based on A packet transfer unit having a packet generation unit that transmits the post-cut rate calculated by the unit to the packet transfer device on the ingress side, the computer on the egress side packet transfer device in the packet transfer system having the egress side This is a packet transfer program for executing a step of cutting an accepted flow based on a post-cut rate transmitted from the packet transfer device.

  As described above, according to the present invention, the forced cutting of the flow can be performed with high accuracy by one type of marking.

It is a figure which shows the structural example of the packet transfer system by one Embodiment of this invention. It is a block diagram which shows the structural example of the multi domain of the packet transfer system by one Embodiment of this invention. It is a figure which shows the relationship between the mark ratio and rate by one Embodiment of this invention. It is a block diagram which shows the structural example of the relay packet transfer apparatus by one Embodiment of this invention. It is a block diagram which shows the structural example of the outgoing line corresponding | compatible part by one Embodiment of this invention. It is a block diagram which shows the example of the token bucket by one Embodiment of this invention. It is a block diagram which shows the example of the boundary packet transfer apparatus by one Embodiment of this invention. It is a flowchart which shows the operation example of the marking process of the packet transfer system by one Embodiment of this invention. It is a flowchart which shows the operation example of the rate management process after a cutting | disconnection of the packet transmission system by one Embodiment of this invention. It is a figure which shows the relationship between the mark ratio and rate in the case of performing reception control by reference. It is a figure which shows the pseudo code which performs reception control by a reference. It is a figure which shows the example of the token bucket which performs reception control by this embodiment. It is a figure which shows the relationship between the mark ratio and rate in the case of performing admission control by this embodiment. It is a figure which shows the pseudo code which performs reception control by a reference. It is a figure which shows the relationship between the mark ratio and rate in the case of performing admission control by this embodiment. It is a figure which shows the structural example of the packet transfer system by a prior art. It is a figure which shows the example by which the route switch was performed in the packet transfer system by a prior art.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a simple configuration example of a packet transfer system 1 according to the present embodiment. Here, a single domain is taken as an example, and the caller terminal 100-1 is connected to the boundary packet transfer apparatus 300-1 on the entrance side, and the boundary packet transfer apparatus 300-1 and the relay packet transfer apparatus 200-1 are connected to the relay packet. It is connected to the boundary packet transfer apparatus 300-2 on the egress side via the transfer apparatus 200-2 and connected to the called party terminal 100-2. FIG. 1 shows an example in which the caller terminal 100-1 and the callee terminal 100-2 are accommodated in one domain, but in the case of crossing multiple domains as shown in FIG. The packet transfer apparatus 300 (entrance side or exit side) connects adjacent domains. In the case of such a multi-domain, for example, the boundary packet transfer apparatus 300-2 transmits the processing result in the own domain to the boundary packet transfer apparatus 300-3 of the adjacent domain.

  In the present embodiment, a plurality of relay packet transfer apparatuses 200 (relay packet transfer apparatus 200-1 to relay packet transfer apparatus 200-4,...) And a plurality of boundary packet transfer apparatuses 300 (boundary packet transfer apparatus 300- 1 to boundary packet transfer apparatus 300-4,..., But the same-named apparatus has the same configuration. Therefore, when there is no need to distinguish between them, relay packet transfer apparatus 200, boundary The packet transfer apparatus 300 will be described. In the present embodiment, a single domain as shown in FIG. 1 will be described as an example.

  First, the relationship between the mark ratio realized by the marking of this embodiment and the traffic rate will be described. FIG. 3 shows a graph of traffic rate and mark ratio in the link of this embodiment. If the traffic rate is lower than the forced disconnection rate (SR), the mark ratio is set to zero. Further, if the traffic rate is higher than the forced disconnection rate (SR) and lower than W × forced disconnection rate (SR), there is a proportional relationship between the mark ratio m and the rate r by the following equation (1). .

  m = r / (W · SR) (SR ≦ r ≦ (W · SR)) (1)

  Here, when the marking is observed with a pair of boundary packet transfer apparatuses 300 on the entrance side and the exit side, the SR is not known because it generally passes through a plurality of links. However, if there is a single bottleneck, there is a proportional relationship between the mark ratio and the reception rate. The mark ratio in SR is 1 / W. From these facts, if x is the reception rate of the ingress / egress packet transfer device pair and y is the mark ratio in the ingress / egress packet transfer device pair, then the rate that can be provided (without forced disconnection) The upper limit value z) of the good rate is expressed by the following formula (2).

  z = x / Wy (2)

  Here, when there are a plurality of bottlenecks in the domain to be managed, the mark is accumulated between the mark ratio and the reception rate by accumulating marks of transmitted packets via the plurality of relay packet transfer apparatuses 200. Proportional relationship does not always hold. In the case of a plurality of bottlenecks, it is expected that a single bottleneck will eventually be obtained by cutting a plurality of times instead of once. This is because it is expected that it is extremely rare that the loads of multiple bottlenecks are all the same. When cutting multiple times, by setting W to be relatively small and increasing the amount of packets to be marked, it is cut so that x = W by one forced cut, and this is repeated. Finally, cut as much as necessary.

Next, the configurations of the relay packet transfer apparatus 200 and the boundary packet transfer apparatus 300 that perform communication control by realizing such a relationship between the mark ratio and the traffic rate will be described.
FIG. 4 is a block diagram showing a configuration of relay packet transfer apparatus 200. The relay packet transfer apparatus 200 includes a plurality of incoming line correspondence units 210, a switch unit 220, and a plurality of outgoing line correspondence units 230. Here, the plurality of incoming line correspondence units 210 and the plurality of outgoing line correspondence units 230 are respectively provided corresponding to the physical lines to which the relay packet transfer apparatus 200 is connected. However, the configuration is the same except that they are connected to different physical lines. Therefore, when there is no need to distinguish between them, they will be described as an incoming line corresponding unit 210 and an outgoing line corresponding unit 230, respectively.

The incoming line correspondence unit 210 has a function of receiving a packet transmitted to the relay packet transfer apparatus 200 and temporarily holding the packet before inputting it to the switch unit 220.
The switch unit 220 compares the routing table stored in its own storage area in advance with the address of the destination included in the packet header of the packet input from the incoming line corresponding unit 310, and the relay packet transfer apparatus 200 includes a plurality of switches. Of the outgoing line corresponding unit 230, the packet is transferred to an appropriate outgoing line corresponding unit 230 according to the destination address.

  The outgoing line correspondence unit 230 forms a rate so as to match the bandwidth (rate) of the output side line, and sends the packet. Further, the outgoing line correspondence unit 230 performs a marking process on the packet to be transmitted. FIG. 5 is a block diagram showing a detailed configuration of the outgoing line correspondence unit 230. The outgoing line correspondence unit 230 includes a token bucket processing unit 231 that performs processing by a token bucket, a marking execution unit 232 that performs marking on a packet, and a waiting queue unit that queues a packet and shapes it into a bandwidth (rate) of a physical line 233 and a physical line corresponding unit 234 that actually sends a packet to the physical line.

  When a packet is input from the switch unit 220, the token bucket processing unit 231 performs a predetermined token bucket process. The token bucket processing unit 231 prepares two token buckets as shown in FIG. The token replenishment rate of the first token bucket (bucket 1, the first bucket) is the forced cut rate (SR), and the token replenishment rate of the other token bucket (bucket 2, the second bucket) is W x forced cut Let it be a rate (SR). A threshold (TB1.threshold) is set for bucket 1. Like a normal token bucket, tokens overflowing from the bucket are discarded.

  The marking execution unit 232 marks the packet according to the processing result of the token bucket processing unit 231. The marking execution unit 232 turns off the marking switch and does not perform any marking when the token bucket processing of the token bucket processing unit 231 accumulates more tokens than the threshold of the bucket 1. On the other hand, the marking execution unit 232 performs marking according to the bucket 2 by turning on the marking switch when the token of the bucket 1 is smaller than the threshold value.

  The packet input to the marking execution unit 232 may have already been marked in the previous packet transfer device. However, for simplicity, in the case of a single bottleneck, that is, no marking is performed in the previous packet transfer device. Explain that has not been done. Here, processing when a packet is already marked by the preceding packet transfer apparatus will be described. Here, there are four cases depending on the combination of whether or not the packet has already been marked by the previous packet transfer device and whether or not the marking has been newly made.

1. No marking already, no new marking 2. No marking already, new marking. Already marked, no new marking 4. Already marked, newly marked

  1. In this case, since both are not marked, only token bucket processing by the token bucket processing unit 231 is performed, and transfer is performed without marking. 4). In this case, marking is originally performed, but since marking has already been performed, only token bucket processing is performed and transferred. 3. In this case, no new marking is performed, but since the marking has already been performed, if the packet is transferred as it is, the ratio of the mark attached by the packet transfer apparatus becomes high.

  Therefore, the marking execution unit 232 stores the number of bytes corresponding to the excess mark packets in its own storage area as a stock separately from the token. The marking execution unit 232 includes: Every time this situation occurs, the stock is added by the number of bytes of the packet that arrived. And 2. On the contrary, when the number of bytes of the arrival packet is subtracted from the stock, no marking is performed when there is a stock to be subtracted, and only when there is no stock to be subtracted, that is, when the stock is zero, Make markings.

  Also, the marking execution unit 232 determines that the token amount of the token bucket 1 by the token bucket processing unit 231 is less than the threshold value, and the token amount of the token bucket 2 at that time is not the token bucket 2 bucket size. Mark. In other cases, the packet is sent to the waiting queue unit 233 without marking. It can be seen from this token bucket that if the rate is lower than SR, no mark is made.

  Furthermore, according to Reference 1 (L. Kleinlock, queuing system theory (above), McGraw-Hill Kogakusha, pp. 17-18), if the packet arrival process follows the Poisson process, regardless of the number of bytes in the packet, It is shown that the mark ratio m is expressed by the above formula (1) when SR ≦ x ≦ W · SR. That is, the usage rate (x / SR) coincides with the value obtained by observing the busy rate (whether the token is not full) according to the Poisson process (PASTA (Poisson Arrivals See Time Average)). Here, when multiple flows are multiplexed, even if the arrival process of packets in the flow does not follow the Poisson process, the multiplexed one is approximated very well by the Poisson process. The above formula (1) holds. According to Reference 2 (DRCox: Renewal Theory, John Wiley & Sons, 1962.), when the packet arrival process in the flow follows the regeneration process, the packet arrival process becomes a Poisson process at the limit of infinite number of flows. It is shown.

  The packet subjected to the marking process by the marking execution unit 232 is sent from the relay packet transfer device 200 by the physical line corresponding unit 234 via the waiting queue unit 233.

  FIG. 7 is a block diagram showing the configuration of the boundary packet transfer apparatus 300. The boundary packet transfer apparatus 300 includes an incoming line correspondence unit 310, an inflow restriction unit 320, a marking totaling unit 330, a packet generation unit 340, a switch unit 350, and an outgoing line correspondence unit 360. Here, the incoming line correspondence unit 310, the switch unit 350, and the outgoing line correspondence unit 360 are the same as the incoming line correspondence unit 210, the switch unit 220, and the outgoing line correspondence unit 230 that are functional units of the same name provided in the relay packet transfer apparatus 200. It is the composition. That is, the boundary packet transfer apparatus 300 has at least the same configuration as all the functional units included in the relay packet transfer apparatus 200.

  The boundary packet transfer apparatus 300 operates differently when it operates as the exit side of the domain and when it operates as the entrance side. First, the process when operating as the exit side will be described. As functions on the exit side, in addition to the functions of the relay packet transfer apparatus 200, there are a marking totaling unit 330 and a packet generation unit 340. When the incoming line corresponding unit 310 receives the packet, the received packet passes through the inflow restricting unit 320 (the inflow restricting unit does not function when on the exit side) and arrives at the marking totaling unit 330.

The marking totalization unit 330 classifies the input packet for each boundary packet transfer device 300 on the entrance side of the domain. Further, when detecting the marked packet, the marking counting unit 330 measures the total number of bytes of the packet that arrived at a predetermined time T and the total number of bytes of the marked packet among the arrived packets. The value of “total number of attached packets / total number of received packets” is calculated as the mark ratio. Further, the marking totaling unit 330 calculates a reception rate that is a value of “total number of received packet bytes / T”.
When the calculated mark ratio is smaller than 1 / W, the marking totaling unit 330 detects the marked packet again without calculating the rate after the flow cut. From these measurement results, the post-cutting rate is calculated as “reception rate / (W × mark ratio)”. The marking totaling unit 330 inputs the calculated post-cutting rate and the corresponding information on the inbound boundary packet transfer apparatus 300 to the packet generation unit 340.
The packet generation unit 340 generates a packet including the information on the rate after disconnection input from the marking totaling unit 330, and the corresponding inbound side boundary packet transfer device via the switch unit 350 and the outgoing line correspondence unit 360 To 300.

  Next, processing when the boundary packet transfer apparatus 300 operates as the entrance side will be described. When the inbound side packet transfer device 300 transmits a packet storing the rate after disconnection from the egress side boundary packet transfer device 300 and receives it by the incoming line corresponding unit 310, the inflow regulation unit 320 It detects that a packet storing the rate has been received. The inflow restricting unit 320 inputs the detected packet to the marking totaling unit 330. The marking totaling unit 330 identifies and determines the egress boundary packet transfer apparatus 300 that is the transmission source of the packet, and measures the number of bytes of the transmitted packet to the egress boundary packet transfer apparatus 300 for each flow. To do. The marking totalization unit 330 calculates the transmission rate for each flow by dividing the total number of transmission bytes for each flow after T time by T. The rate of difference between the sum of the transmission rates of all flows and the rate after the flow cut is obtained, and the flow to be cut is selected so that the difference rate and the sum of the transmission rates of a plurality of flows match. The marking totalization unit 330 transmits the selected flow list to the inflow regulation unit 320. The inflow restricting unit 320 deletes the information of the flow selected from the pending flow list stored in its own storage area. Thereafter, even if a packet belonging to the disconnected flow is transmitted, the inflow restricting unit 320 does not transfer the packet to the pending flow list and discards the packet. As a result, it is forcibly disconnected. If these disconnected flows can be accepted again by the acceptance control, they are added to the pending list again and allowed to flow into the network.

Next, an operation example of the packet transfer system 1 of the present embodiment will be described with reference to the drawings. FIG. 8 is a flowchart showing an example of the marking process performed by the relay packet transfer apparatus 200 according to this embodiment. However, the operation example of the marking process by the boundary packet transfer apparatus 300 is the same.
In this figure, ta is the time when a packet arrives at the relay packet transfer apparatus 200, LCT is the time when the previous packet arrives at the relay packet transfer apparatus 200, token1 and token2 are tokens stored in buckets 1 and 2, respectively. Tc1 and Tc2 are the token amounts of bucket 1 and bucket 2 at the time of arrival of the packet, and TB. Size1, TB. Size2 is the size of bucket 1 and bucket 2, and pk.Size is the packet size [byte]. Stk represents stock.

  The marking execution unit 232 substitutes 0 for stock (stk) at the start of processing (step S1). When the packet arrives at the outgoing line correspondence unit 230, the token bucket processing unit 231 substitutes SR × (ta−LCT) for token1, and substitutes W × SR × (ta−LCT) for token2 (step S3). The token bucket processing unit 231 determines whether the value (Tc1 + token1) obtained by adding a token to the bucket 1 exceeds the size (TB.Size1) of the bucket 1, or the value (Tc2 + token2) obtained by adding the token to the bucket 2 is the size of the bucket 2. It is determined whether or not (TB.Size2) is exceeded (step S4).

  In step S4, the token bucket processing unit 231 determines that the value (Tc1 + token1) obtained by adding the token to the bucket 1 exceeds the size (TB.Size1) of the bucket 1 or the value (Tc2 + token2) obtained by adding the token to the bucket 2 If it is determined that the size exceeds the size of bucket 2 (TB.Size2), TB. Substitute the value of Size1 and set TB. The value of Size2 is substituted (step S6). On the other hand, if the token bucket processing unit 231 determines in step S4 that the token amount of the bucket including the token does not exceed the bucket size, the token bucket processing unit 231 adds the token to the bucket (step S5).

  Then, the token bucket processing unit 231 subtracts pk.Size from Tc1 (step S7). Then, the token bucket processing unit 231 determines whether Tc1 is smaller than 0 (step S8). If the token bucket processing unit 231 determines that Tc1 is smaller than 0, 0 is substituted for Tc1 (step S9). On the other hand, if the token bucket processing unit 231 determines that Tc1 is equal to or greater than 0, the token bucket processing unit 231 determines whether Tc1 is equal to or greater than the threshold value of TB1 (step S10). If it is determined that Tc1 is equal to or greater than the threshold value of TB1, the process proceeds to step S20. If the token bucket processing unit 231 determines that Tc1 is not equal to or greater than the threshold value of TB1, the marking execution unit 232 determines that TC2 and Tb. It is determined whether Size2 matches (step S11).

  The marking execution unit 232 includes TC2 and Tb. If it is determined that Size2 matches, it is determined whether or not there is already a mark in the packet (step S12). If it is determined that there is already a mark in the packet, the marking execution unit 232 adds the packet size to the stock (step S13). If it is determined that there is no mark in the packet, the process proceeds to step S20. In step S11, the marking execution unit 232 performs the TC2 and Tb. If it is determined that Size2 does not match, it is determined whether or not there is already a mark in the packet (step S14). If the marking execution unit 232 determines that there is already a mark in the packet, the process proceeds to step S20.

  On the other hand, if the marking execution unit 232 determines in step S14 that there is no mark in the packet, it determines whether the stock is greater than 0 (step S15). If the marking execution unit 232 determines that the stock is larger than 0, the packet size is subtracted from the stock (step S16). And the marking implementation part 232 determines whether a stock is smaller than 0 (step S17). If it is determined that the stock is smaller than 0, the marking execution unit 232 stores the stock as 0 (step S18). If it is determined that the stock is 0 or more, the process proceeds to step S20.

  If it is determined in step S15 that the stock is 0 or less, the marking performing unit 232 marks the packet (step S19). Then, the packet size is subtracted from the token amount of the bucket 2 (step S20). The token bucket processing unit 231 determines whether or not the token amount of the bucket 2 is smaller than 0 (step S21). If it is determined that the token amount of the bucket 2 is smaller than 0, the token bucket processing unit 231 sets the token amount of the bucket 2 to 0 (step S22). If it is determined that the token amount of bucket 2 is 0 or more, the process returns to step S2.

FIG. 9 is a flowchart illustrating an operation example of notification processing by the egress boundary packet transfer apparatus 300 according to this embodiment.
The marking totaling unit 330 includes the packet input via the inflow regulating unit 320.
It is determined whether or not a marked packet is included (step S30). The marking totaling unit 330 repeats the process of step S30 if the marked packet is not included. If a marked packet is included, the reception rate and mark ratio are calculated (step S31). Then, it is determined whether or not the mark ratio is greater than 1 / W (step S32). If marking totaling unit 330 determines that the mark ratio is greater than 1 / W, it returns to step S30. If it is determined that the mark ratio is 1 / W or less, the value of reception rate / (W × mark ratio) is calculated as the post-cutting rate (step S33). The marking totaling unit 330 notifies the packet generation unit 340 of the post-cut rate and the information on the corresponding boundary packet transfer device 300 on the ingress side. The packet generation unit 340 generates a packet in which information indicating the rate after disconnection is stored, and transmits the packet to the information of the corresponding boundary packet transfer apparatus 300 on the ingress side.

  In the above, an example in which the outgoing line handling unit 230 performs marking for forced disconnection has been described, but the reception control can be performed using the same type of marking. That is, the outgoing line handling unit 230 performs a marking process that combines marking for admission control and marking for forced disconnection. The admission control is described in, for example, Reference 3 (Satoh et al., “Single PCN Threshold Marking by using PCN baseline encoding for both admission and termination controls,” Internet Draft: draft-satoh-pcn-st-marking-02.txt, Internet Engineering Task Force, September 2009).

  In this method, the relationship between the rate and the mark ratio as shown in FIG. 10 is realized, and three areas are distinguished by one type of mark. In this figure, the rate where the mark ratio is not 1 is the area where the admission control is performed. Thereby, it is possible to prevent the flow from being erroneously cut when the cutting is originally unnecessary due to the accumulation of marks. FIG. 11 is a pseudo code showing a token bucket process according to this method. Here, SwTB is used to replenish tokens at the admission control rate (used for the purpose of not marking when the traffic rate is lower than the admission control rate), and MkTB is used to replenish tokens at the forced disconnection rate (acceptance). The token bucket is used to partially mark the traffic when the traffic rate is higher than the control rate.

  In this figure, SwTB.size and MkTB.size indicate the sizes of SwTB and MkTB, respectively, SwTB.fill and MkTB.fill indicate the token amounts of SwTB and MkTB, respectively, and SwTB.rate and MkTB.rate are Shows the token replenishment rate (ie, admission control rate and forced disconnection rate) of SwTB and MkTB, respectively. SwTB.Threshold and MkTB.Threshold indicate the thresholds of SwTB and MkTB, respectively, and packet.size indicates the size of the arrived packet. , Packet.mark indicates the mark state of the packet, markCnt indicates a counter, lastUpdate indicates the time of the last update in two buckets, and now indicates the current time.

  When combining the above-mentioned forced disconnection token bucket process and the reception control token bucket process, three token buckets are used as shown in FIG. The change is that when a bucket (bucket 0) is newly replenished at the admission control rate, and when tokens are accumulated more than TB1.threshold in bucket 1, the marking switch is not turned OFF but in N packets. To mark one packet. In the newly added bucket 0, the threshold value TB0.threshold is set as in the case of the bucket 1, and when tokens are accumulated beyond this threshold value, the marking switch is turned off and no mark is attached. When the token is lower than TB0.threshold, the marking switch for bucket 1 is turned on and processing is performed according to bucket 1. The packet generation unit 340 generates a packet including a notification indicating whether or not the ingress side boundary packet transfer apparatus 300 rejects reception of the packet according to the ratio of the marked packets, and performs ingress side boundary packet transfer. To device 300. The inflow restricting unit 320 of the ingress boundary packet transfer apparatus 300 that has received the notification indicating that the acceptance is rejected rejects the acceptance of the new flow.

  When such a compulsory disconnect token bucket process is combined with a token bucket process for admission control, the relationship between the rate and the mark ratio is as shown in FIG. Here, it is important to create a gap with a mark ratio when the rate is the forced cutting rate. That is, it is necessary to make the mark ratio of the forced cutting rate in this embodiment sufficiently higher than the mark ratio in Reference Document 3.

  Alternatively, as a marking process for admission control, Reference 4 (Menth, M., et al., “A Survey of PCN-Based Admission Control and Flow Termination, IEEE Communications Survey and Tutorials, to appear.) And Reference 5 (Sato) , Ueno, Maeda: Even if the admission control method described in the performance evaluation of the PCN algorithm that expresses three bandwidth regions with a single mark, and IEICE Technical Report IN2009-88, pp.7-12, 2009.) is applied. In this method, the mark ratio with respect to the rate is such that the straight line between the acceptance control rate and the forced disconnection rate shown in Fig. 13 is parallel to the horizontal axis, and the traffic rate is higher than the acceptance control rate. Marks are made at a ratio of 1 / N, and all marks are made when the forced cutting rate is exceeded.

  FIG. 14 is a diagram showing pseudo code of this method. Fr.TB is a token bucket for marking at a ratio of 1 / N, and Th.TB is a token bucket for marking all. In this case as well, it is important to create a gap in the mark ratio at the forced cutting rate as in the above-described method. This marking is called fractional marking. Here, FrTB. Size and ThTB.Size are the sizes of FrTB and ThTB, respectively, and FrTBP. fill, ThTB.fill are FrTB, ThTB token amount, FrTB.Rate, ThTB. rate is a token replenishment rate of FrTB and ThTB, that is, an admission control rate and a forced disconnection rate, respectively. Threshold, ThTB. Threshold is a threshold value of FrTB and ThTB, respectively, packet. Size is the size of the incoming packet, packet. mark is the mark state of the packet, markCnt is a counter, lastUpdate is the last update time in two buckets, and now is the current time.

  When combining the above-mentioned forced disconnection token bucket process with this type of admission control token bucket process, three token buckets are used as shown in FIG. The changes are that a bucket (bucket 0) is newly refilled at the admission control rate, and that a new bucket is added instead of the marking switch OFF when tokens are accumulated from TB1.threshold in bucket 1. Marking according to 0. In other words, the bucket 1 sorts whether the newly added bucket 0 or bucket 2 performs the marking process. In the newly added bucket 0, the threshold value TB0.threshold is set in the same manner as described above. When tokens are accumulated beyond this threshold value, no mark is added, and the token is lower than TB0.threshold. In some cases, fractional marking is performed according to the above algorithm.

  As described above, according to the present embodiment, it is possible to directly measure and obtain the amount of cutting for forced cutting when the flow becomes excessive, without estimation. Further, since the mark ratio when the forced cutting rate is exceeded according to W is obtained, the forced cutting rate is higher than the mark ratio in consideration of the accumulation of marks by a plurality of bottleneck links. If W is set so as to increase the mark ratio when exceeding the limit, whether or not the actual traffic rate exceeds the forced disconnection rate depending on the mark ratio under the constraint that only the state with mark and without mark can be expressed Can be determined.

  Further, in the prior art, when forcibly cutting an excessive flow, a rate of a ratio determined by one cutting is cut and this is repeated to finally cut a necessary amount. In this case, if a predetermined proportion is reduced, accuracy increases, but cutting takes time. On the other hand, if the ratio is increased, the time required for cutting will be reduced, but the accuracy will deteriorate. Furthermore, when the excess of the actual traffic rate from the forced disconnection rate is smaller than the amount of disconnection at one time, the excessive disconnection is always performed. That is, in the prior art, for example, the flow is forcibly cut at a constant rate, and even if it eventually becomes a single bottleneck, it can be cut only at a constant rate. Cutting is possible. In addition, according to the present embodiment, since an appropriate cutting amount can be known if it is a single bottleneck, it is possible to set the amount to be cut at a time larger than in the prior art.

  Note that a program for realizing the function of the processing unit in the present invention is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed to perform communication control. May be. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer system” includes a WWW system having a homepage providing environment (or display environment). The “computer-readable recording medium” refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a storage device such as a hard disk built in the computer system. Further, the “computer-readable recording medium” refers to a volatile memory (RAM) in a computer system that becomes a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. In addition, those holding programs for a certain period of time are also included.

  The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

DESCRIPTION OF SYMBOLS 1 Packet transfer system 100-1 Caller terminal 100-2 Callee terminal 200 Relay packet transfer apparatus 210 Incoming line corresponding part 220 Switch part 230 Outgoing line corresponding part 231 Token bucket processing part 232 Marking execution part 233 Wait queue part 234 Physical line Corresponding unit 300 Boundary packet transfer device 310 Incoming line corresponding unit 320 Inflow restricting unit 330 Marking totaling unit 340 Packet generating unit 350 Switch unit 360 Outgoing line corresponding unit

Claims (10)

In a domain configured by a plurality of packet transfer apparatuses, an ingress packet that receives a packet transmitted from outside the domain that is arranged on the ingress side of the domain and receives a flow of real-time communication by transmitting the packet into the domain A forwarding device, a relay packet forwarding device that receives and relays a packet transmitted within the domain, and an exit side that is arranged on the exit side of the domain and receives the packet through the domain and forwards it outside the domain A packet transfer system comprising a packet transfer device,
The ingress packet transfer device and the relay packet transfer device are:
A first token bucket process by a first token bucket whose predetermined forced disconnection rate is a token replenishment rate, and a second token whose predetermined multiple of the forced disconnection rate is a token replenishment rate A token bucket processing unit for performing a second token bucket processing by the bucket;
If the token amount in the first token bucket exceeds a predetermined threshold according to the processing result by the token bucket processing unit, the packet is not marked, and the token amount in the first token bucket A marking execution unit that performs marking on the packet in accordance with the second token bucket processing when is equal to or less than a predetermined threshold,
The egress packet transfer device is:
A mark ratio, which is a ratio between the total amount of packets transmitted from the ingress packet transfer device and the amount of packets marked by the marking execution unit among the packets transmitted from the ingress packet transfer device; A marking counting unit for calculating a rate after disconnection based on a reception rate of packets transmitted from the packet transfer device on the entrance side and the constant;
A packet generation unit that transmits the post-cutting rate calculated by the marking totaling unit to the packet transfer device on the ingress side, and
The ingress packet transfer device is:
An inflow restricting section for cutting off the accepted flow based on the post-cut rate transmitted from the packet transfer apparatus on the exit side. The token bucket processing unit
Perform the admission control token bucket process with the admission control token bucket whose predetermined admission control rate is the token replenishment rate,
The marking processing unit
In accordance with the admission control token bucket process, marking is performed on the packet at a predetermined rate of once every plural times,
The packet generation unit of the packet transfer device on the egress side,
A notification indicating whether or not the packet transfer device on the ingress side rejects acceptance of the packet according to the mark ratio is transmitted to the packet transfer device on the ingress side;
The inflow restricting portion of the packet transfer apparatus on the entrance side is
The packet transfer system according to claim 1, wherein admission control is performed based on the notification transmitted from the packet transfer apparatus on the egress side. The marking execution unit
If the already marked packet is input and marking is not performed by itself, the number of bytes corresponding to the packet is added and stored as stock information, the unmarked packet is input, and marking is performed by itself. 3. The packet according to claim 1, wherein if it is determined to be performed, the number of bytes corresponding to the packet is subtracted from the number of bytes indicated by the stock information, and the packet is not marked. Transfer system. In a domain configured by a plurality of packet transfer apparatuses, an ingress packet that receives a packet transmitted from outside the domain that is arranged on the ingress side of the domain and receives a flow of real-time communication by transmitting the packet into the domain A forwarding device, a relay packet forwarding device that receives and relays a packet transmitted within the domain, and an exit side that is arranged on the exit side of the domain and receives the packet through the domain and forwards it outside the domain The ingress packet transfer device or the relay packet transfer device in a packet transfer system comprising a packet transfer device,
A first token bucket process by a first token bucket whose predetermined forced disconnection rate is a token replenishment rate, and a second token whose predetermined multiple of the forced disconnection rate is a token replenishment rate A token bucket processing unit for performing a second token bucket processing by the bucket;
If the token amount in the first token bucket exceeds a predetermined threshold according to the processing result by the token bucket processing unit, the packet is not marked, and the token amount in the first token bucket A marking execution unit that performs marking on the packet in accordance with the second token bucket processing when is equal to or less than a predetermined threshold;
A packet transfer apparatus comprising: In a domain constituted by a plurality of packet transfer apparatuses, a packet transmitted from outside the domain that is arranged on the entrance side of the domain is received and transmitted into the domain, and a flow of real-time communication is accepted and determined in advance. A first token bucket process by a first token bucket in which the forced forced disconnection rate is a token replenishment rate, and a second token bucket in which a predetermined multiple of the forced disconnection rate is a token replenishment rate. A token bucket processing unit that performs a second token bucket process, and if the token amount in the first token bucket exceeds a predetermined threshold according to a processing result by the token bucket processing unit, The talk in the first token bucket without marking An ingress packet transfer device having a marking execution unit for marking the packet according to the second token bucket process when the amount is equal to or less than a predetermined threshold, and a packet transmitted in the domain A relay packet transfer apparatus having the token bucket processing unit and the marking execution unit, and an exit that is arranged on the exit side of the domain and receives the packet through the domain and transfers it outside the domain The egress side packet transfer apparatus in a packet transfer system comprising a side packet transfer apparatus,
A mark ratio, which is a ratio between the total amount of packets transmitted from the ingress packet transfer device and the amount of packets marked by the marking execution unit among the packets transmitted from the ingress packet transfer device; A marking counting unit for calculating a rate after disconnection based on a reception rate of packets transmitted from the packet transfer device on the entrance side and the constant;
A packet generation unit for transmitting the post-cut rate calculated by the marking totaling unit to the packet transfer device on the ingress side;
A packet transfer apparatus comprising: In a domain constituted by a plurality of packet transfer apparatuses, a packet transmitted from outside the domain that is arranged on the entrance side of the domain is received and transmitted into the domain, and a flow of real-time communication is accepted and determined in advance. A first token bucket process by a first token bucket in which the forced forced disconnection rate is a token replenishment rate, and a second token bucket in which a predetermined multiple of the forced disconnection rate is a token replenishment rate. A token bucket processing unit that performs a second token bucket process, and if the token amount in the first token bucket exceeds a predetermined threshold according to a processing result by the token bucket processing unit, The talk in the first token bucket without marking An ingress packet transfer device having a marking execution unit for marking the packet according to the second token bucket process when the amount is equal to or less than a predetermined threshold, and a packet transmitted in the domain The relay packet transfer device having the token bucket processing unit and the marking execution unit, and receiving the packet through the domain and transferring the packet outside the domain, A mark ratio, which is a ratio between the total amount of packets transmitted from the ingress packet transfer device and the amount of packets marked by the marking execution unit among the packets transmitted from the ingress packet transfer device; A reception rate of packets transmitted from the packet transfer apparatus on the entrance side; An egress-side packet having a marking totaling unit that calculates a post-cutting rate based on the constant, and a packet generation unit that transmits the post-cutting rate calculated by the marking totaling unit to the ingress-side packet transfer apparatus The ingress packet transfer apparatus in a packet transfer system comprising a transfer apparatus,
A packet transfer apparatus comprising: an inflow restricting section that disconnects the received flow based on the post-cut rate transmitted from the packet transfer apparatus on the exit side. In a domain configured by a plurality of packet transfer apparatuses, an ingress packet that receives a packet transmitted from outside the domain that is arranged on the ingress side of the domain and receives a flow of real-time communication by transmitting the packet into the domain A forwarding device, a relay packet forwarding device that receives and relays a packet transmitted within the domain, and an exit side that is arranged on the exit side of the domain and receives the packet through the domain and forwards it outside the domain A packet transfer method of a packet transfer system comprising a packet transfer device,
The ingress packet transfer device and the relay packet transfer device are:
A first token bucket process by a first token bucket whose predetermined forced disconnection rate is a token replenishment rate, and a second token whose predetermined multiple of the forced disconnection rate is a token replenishment rate Performing a second token bucket process with a bucket;
When the token amount in the first token bucket exceeds a predetermined threshold, marking is not performed on the packet, and when the token amount in the first token bucket is equal to or less than a predetermined threshold. Marking the packet according to the second token bucket process;
The egress packet transfer device is
A mark ratio, which is a ratio between the total amount of packets transmitted from the ingress packet transfer device and the amount of packets marked by the marking execution unit among the packets transmitted from the ingress packet transfer device; Calculating a rate after disconnection based on a reception rate of packets transmitted from the packet transfer device on the ingress side and the constant;
Transmitting the post-cutting rate calculated by the marking tabulation unit to the ingress packet transfer device;
The ingress packet transfer device is
Cutting the accepted flow based on the post-cut rate transmitted from the egress packet transfer device;
A packet transfer method comprising: In a domain configured by a plurality of packet transfer apparatuses, an ingress packet that receives a packet transmitted from outside the domain that is arranged on the ingress side of the domain and receives a flow of real-time communication by transmitting the packet into the domain A forwarding device, a relay packet forwarding device that receives and relays a packet transmitted within the domain, and an exit side that is arranged on the exit side of the domain and receives the packet through the domain and forwards it outside the domain A computer of the ingress packet transfer device or the relay packet transfer device in a packet transfer system comprising a packet transfer device;
A first token bucket process by a first token bucket whose predetermined forced disconnection rate is a token replenishment rate, and a second token whose predetermined multiple of the forced disconnection rate is a token replenishment rate Performing a second token bucket process with a bucket;
If the token amount in the first token bucket exceeds a predetermined threshold according to the processing result by the token bucket processing unit, the packet is not marked, and the token amount in the first token bucket Marking the packet according to the second token bucket process if is less than or equal to a predetermined threshold; and
Packet transfer program that executes In a domain constituted by a plurality of packet transfer apparatuses, a packet transmitted from outside the domain that is arranged on the entrance side of the domain is received and transmitted into the domain, and a flow of real-time communication is accepted and determined in advance. A first token bucket process by a first token bucket in which the forced forced disconnection rate is a token replenishment rate, and a second token bucket in which a predetermined multiple of the forced disconnection rate is a token replenishment rate. A token bucket processing unit that performs a second token bucket process, and if the token amount in the first token bucket exceeds a predetermined threshold according to a processing result by the token bucket processing unit, The talk in the first token bucket without marking An ingress packet transfer device having a marking execution unit for marking the packet according to the second token bucket process when the amount is equal to or less than a predetermined threshold, and a packet transmitted in the domain A relay packet transfer apparatus having the token bucket processing unit and the marking execution unit, and an exit that is arranged on the exit side of the domain and receives the packet through the domain and transfers it outside the domain A computer of the egress packet transfer device in a packet transfer system comprising a side packet transfer device,
A mark ratio, which is a ratio between the total amount of packets transmitted from the ingress packet transfer device and the amount of packets marked by the marking execution unit among the packets transmitted from the ingress packet transfer device; Calculating a rate after disconnection based on a reception rate of packets transmitted from the packet transfer device on the ingress side and the constant;
Transmitting the calculated post-cut rate to the ingress packet transfer device;
Packet transfer program that executes In a domain constituted by a plurality of packet transfer apparatuses, a packet transmitted from outside the domain that is arranged on the entrance side of the domain is received and transmitted into the domain, and a flow of real-time communication is accepted and determined in advance. A first token bucket process by a first token bucket in which the forced forced disconnection rate is a token replenishment rate, and a second token bucket in which a predetermined multiple of the forced disconnection rate is a token replenishment rate. A token bucket processing unit that performs a second token bucket process, and if the token amount in the first token bucket exceeds a predetermined threshold according to a processing result by the token bucket processing unit, The talk in the first token bucket without marking An ingress packet transfer device having a marking execution unit for marking the packet according to the second token bucket process when the amount is equal to or less than a predetermined threshold, and a packet transmitted in the domain The relay packet transfer device having the token bucket processing unit and the marking execution unit, and receiving the packet through the domain and transferring the packet outside the domain, A mark ratio, which is a ratio between the total amount of packets transmitted from the ingress packet transfer device and the amount of packets marked by the marking execution unit among the packets transmitted from the ingress packet transfer device; A reception rate of packets transmitted from the packet transfer apparatus on the entrance side; An egress-side packet having a marking totaling unit that calculates a post-cutting rate based on the constant, and a packet generation unit that transmits the post-cutting rate calculated by the marking totaling unit to the ingress-side packet transfer apparatus A packet transfer device computer on the entrance side in a packet transfer system comprising a transfer device;
A packet transfer program for executing the step of cutting the accepted flow based on the post-cut rate transmitted from the packet transfer device on the egress side.

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