JP5896055B2 - Priority setting device and computer program - Google Patents

Description

  The present invention relates to an apparatus for setting a priority used for priority control packet communication, and a computer program for causing a computer to execute the priority setting process.

With the broadbandization of the Internet, the importance of QoS (Quality of Service) that guarantees the quality of stream data such as video and audio is increasing.
If such a network device that supports QoS is used, it is possible to preferentially send and receive the above-mentioned traffic that does not make sense when a delay occurs, rather than a file exchange software packet that does not particularly affect the delay. This improves the convenience and usability of the network.

A packet relay apparatus that supports such a QoS usually has a plurality of transmission queues having different priorities, and mapping of which priority queue is used to transmit a relayed packet is performed according to a predetermined header field value. (See Patent Document 1).
For example, when the packet to be relayed is an IP packet, mapping to a plurality of priority queues is performed according to the values of the IP-Protocol (protocol number) field and the TCP / UDP port field.

JP 2010-4310 A

However, in recent communication networks, traffic premised on the Web has become the mainstream, and the mapping method based on the value of the header field as described above is likely to result in traffic of the same priority queue ( For example, in the case of an HTTP packet, IP-Proto = 6, Port = 80), user convenience may not be significantly improved.
In this case, the priority of a desired packet may be set in consideration of the source and destination IP addresses, etc., but it is extremely complicated for the user himself to make this setting.

  In addition, since QoS is a technique for improving the “user experience” (user's feeling of use / satisfaction) in the entire communication network, it is not preferable for the user to arbitrarily change the priority of a desired packet. It is desirable to change the priority flexibly according to the state.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional problems, and it is an object of the present invention to make it possible to flexibly change the priority in accordance with the state of a network in priority control packet communication.

  (1) A priority setting device according to the present invention is a priority setting device that automatically sets a priority used for packet communication of a priority control method, and acquires a plurality of packets having the same transmission / reception node. And a setting unit that sets the priority of the packet according to the inter-packet delay of the acquired plurality of packets.

  According to the priority setting apparatus of the present invention, the setting unit sets the priority of the packet according to the inter-packet delay of the acquired plurality of packets. If the packet has a higher priority than the current status and increases the quality, and if the packet delay is smaller than normal, set the priority to a lower priority than the current status to decrease the quality. The priority can be changed flexibly.

(2) In the priority setting apparatus of the present invention, a calculation unit that calculates a first delay amount that is a statistic of the inter-packet delay based on acquisition times of the plurality of packets acquired in a predetermined period. If provided, the setting unit may set the priority of the packet based on the difference between the calculated first delay amount and the reference delay amount in the normal state.
In this case, for example, when the difference obtained by subtracting the reference delay amount from the first delay amount exceeds a predetermined threshold value, it can be determined that the inter-packet delay of the packet has increased. It can be determined that it is not so intense.

  In the present specification, the “period” refers to a predetermined time length (for example, 10 seconds) for collecting a plurality of packets, which is necessary for calculating a statistic (for example, an average value) of delay between packets. The unit time.

(3) In the priority setting device of the present invention, the calculation unit calculates a second delay amount that is a statistic of the plurality of first delay amounts calculated for each period, and calculates the second delay It is preferable to employ a delay amount as the reference delay amount.
In this case, since the reference delay amount is a second delay amount that is a statistic amount (for example, an average value) of a plurality of first delay amounts, compared to the case where the reference delay amount is set to a fixed value, the normal network The state can be set more appropriately.

(4) However, in this case, it is preferable that the calculation unit excludes the first delay amount whose difference from the reference delay amount is a predetermined threshold value or more from the second delay amount calculation element.
In this case, it is possible to prevent an inaccurate reference delay amount from being set by using the first delay amount indicating an abnormal value as an element for calculating the second delay amount.

(5) In the priority setting apparatus of the present invention, the inter-packet delay is, for example, a time difference between the same type of packets transmitted continuously from one node to the other node, that is, the packet is received at each reception time. It consists of the time difference between the adjacent ones when they are arranged.
In this case, it is possible to set the priority of packets between transmission and reception nodes that use broadcast communication such as UDP.

(6) The inter-packet delay may be a time difference between a request packet from one node to the other and a response packet corresponding to the request packet.
In this case, it is possible to set the priority of packets between transmission / reception nodes that perform handshaking such as HTTP Get and Response.

  (7) The computer program of the present invention is a computer program for causing a communication device capable of packet communication to function as a device for setting a priority used in priority control packet communication, and has the same transmission / reception node. The method includes a step of acquiring a plurality of packets, and a step of setting a priority of the packets according to inter-packet delays of the plurality of acquired packets.

As described above, the computer program of the present invention is substantially the same invention as the relay apparatus of the present invention, and has the same effects as the apparatus.
The computer program of the present invention may include the matters described in the above (2) to (6).

  As described above, according to the present invention, the priority can be flexibly changed according to the state of the network in the packet communication of the priority control method.

1 is an overall configuration diagram of a communication system to which a router (relay device) as an example of a priority setting device according to the present invention is applied. It is a block diagram which shows the internal structure of a router. It is a schematic flowchart which shows the process sequence of a packet processor. It is a figure which shows an example of a rule table. It is a figure which shows an example of a flow table. It is a figure which shows the data structure of flow data. It is an example of a series of flow data in the same direction, and its sequence diagram. It is an example of a series of flow data bidirectionally, and its sequence diagram. It is a figure which shows an example of a flow mapping table. It is a figure which shows the data structure of flow statistics data and baseline data. It is a flowchart (first half) which shows the update process of flow statistical data. It is a flowchart (second half) which shows the update process of flow statistical data.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Overall system configuration]
FIG. 1 is an overall configuration diagram of a communication system to which a router (relay apparatus) as an example of a priority setting apparatus according to the present invention is applied.
As shown in FIG. 1, this communication system includes an OLT 1 that is an optical line terminating device on the telecommunications carrier side, an ONU 2 that is an optical line terminating device on the home side, a router 3 including a home gateway, a broadband router, and the like. IP terminal 4 and the like.

The OLT 1 and the ONU 2 are connected by an optical fiber via an optical coupler, and the OLT 1 is connected to the wide area network 6. The wide area network 6 of the present embodiment is the Internet.
In the system configuration example of FIG. 1, the line termination device composed of the ONU 2 is illustrated assuming FTTH, but an ADSL modem or a CATV modem may be employed as another line termination device.

The ONU 2 and the router 3 are connected to each other via an Ethernet cable (note: “Ethernet” is a registered trademark) 7.
The router 3 is a relay device having an IP packet routing function, and has one WAN port and one or a plurality of LAN ports. In the illustrated example, the router 3 having two LAN ports is illustrated, but the number is not limited to two.

Various IP terminals 4 are connected to the LAN port of the router 3 via an Ethernet cable 9. The IP terminal 4 is made of, for example, a home appliance such as a personal computer (PC) capable of IP communication, a server computer, or a television.
Further, an IP terminal 4 is also connected to the wide area network 6 on the OLT 1 side, and this IP terminal 4 is composed of, for example, a cloud server.

“LAN1” shown in FIG. 1 is a local network connected to one LAN port of the router 3, and “LAN2” is a local network connected to the other LAN port of the router 3.
These local networks LAN1 and LAN2 are configured by multi-stage connection using one or a plurality of switching hubs 10, and have an IP terminal 4 at a terminal portion of the network.

On the other hand, the router 3 is a target device for management and monitoring of network devices performed by the IP terminal 4 such as the PCs of the local networks LAN1 and LAN2, and an agent program operated by the control program of the IP terminal 4 is assigned to the router 3. Installed.
The agent program of the router 3 performs a capturing process for capturing an IP packet routed by the router 3, a QoS priority automatic setting process using the captured packet, and the like.

In addition to the IP packet relay function, the router 3 of the present embodiment includes an IP packet dynamic filtering function, a NAT function, a DHCP function, a PPPoE function, an ARP function, and the like.
Note that “packet” may be used as a name of a PDU used in layer 3 communication, but in this specification, the meaning of a unit for sending data used for communication between computers (thus, the same as PDU). But use. Therefore, the “IP packet” may be simply referred to as “packet”.

[Internal configuration of router]
FIG. 2 is a block diagram showing the internal configuration of the router 3.
As shown in FIG. 2, the router 3 includes a first interface unit 301, a first transmission / reception driver 302, a capture reception buffer 303, a first transmission buffer 304, a second interface unit 305, a second transmission / reception driver 306, and relay reception. A buffer 307, a second transmission buffer 308, a packet processor 309, and the like are provided.

The first interface unit 301 is an Ethernet specification transceiver having a WAN port, and the first transmission / reception driver 302 includes a drive circuit that causes the first interface unit 301 to transmit and receive packets.
The first transmission / reception driver 302 passes the reception packet received from the first interface unit 301 to the capture reception buffer 303 and the relay reception buffer 307, and transmits the transmission packet received from the first transmission buffer 304 from the first interface unit 301 to the outside. To send.

The second interface unit 305 is an Ethernet specification transceiver having a LAN port, and the second transmission / reception driver 306 includes a drive circuit that causes the second interface unit 305 to transmit and receive packets.
The second transmission / reception driver 306 passes the reception packet received from the second interface unit 305 to the capture reception buffer 303 and the relay reception buffer 307, and transmits the transmission packet received from the second transmission buffer 308 from the second interface unit 305 to the outside. To send.

The first and second transmission buffers 304 and 308 have a plurality of queues H and L having different priorities.
Among the plurality of queues H and L, the high priority queue H is a transmission queue for storing high priority transmission packets after relay processing is performed by the router 3, and the low priority queue L Is a transmission queue for storing low-priority transmission packets after relay processing is performed by the router 3.

The first interface unit 301, the first transmission / reception driver 302, the capture reception buffer 303, and the first transmission buffer 304 constitute a “transmission / reception unit” on the WAN side.
The second interface unit 305, the second transmission / reception driver 306, the relay reception buffer 307, and the second transmission buffer 308 constitute a “transmission / reception unit” on the LAN side.

[Functional part of packet processor]
The packet processor 309 includes a relay processing unit 310, a capture processing unit 311, a classification processing unit 312, and a data processing unit 313.
These processing units are realized by the processor 309 reading out and executing a computer program (specifically, the agent program) stored in a known storage device (not shown) such as a ROM or a RAM. Is a functional part.

As described above, the predetermined computer program for realizing each processing unit is installed in a storage device (not shown). This computer program is stored in a recording medium such as a CD-ROM or a DVD-ROM for sale or Can be transferred.
The computer program can be sold or transferred by downloading it from a server computer via a network.

Relay reception buffer 307 stores a predetermined amount of all received packets received from transmission / reception drivers 302 and 306, and outputs the stored received packets to relay processing unit 310.
When the relay processing unit 310 generates a transmission packet by performing predetermined routing processing and conversion of address information and port information by NAT (Network Address Translation) on the received packet input from the buffer 307, a flow mapping described later is performed. With reference to table FMT (FIG. 9), QoS priority mapping is performed to generate a transmission packet, and the transmission packet is input to transmission buffers 304 and 308.

That is, in the case of a transmission packet with an address for which QoS is set to high priority in the flow mapping table FMT, the relay processing unit 310 has a high priority queue H in any of the transmission buffers 304 and 308 corresponding to the destination address. To enter.
In addition, in the case of a transmission packet having an address for which QoS is set to low priority in the flow mapping table FMT, the relay processing unit 310 uses the low priority queue L of one of the transmission buffers 304 and 308 corresponding to the destination address. To enter.

The capture reception buffer 303 accumulates a predetermined amount of all received packets received from the respective reception drivers 302 and 306, and outputs the accumulated received packets to the capture processing unit 311.
The capture processing unit 311 performs predetermined processing such as rearranging the received packets input from the buffer 303 according to the reception time, and sends all received packets to the classification processing unit 312 and the data processing unit 313.

The classification processing unit 312 extracts header information from the received packet received from the capture processing unit 311 and applies the rule table RT and the flow table FT to the header information to generate “flow data FD”. The classification processing unit 312 temporarily stores the data FD in the data buffer 315.
The classification processing unit 312 stores data that cannot be classified as flow data FD in the data buffer 315 as unregistered data.

  The data processing unit 313 performs update processing of “flow statistical data FSD” that includes “first delay amount” that is an average value of inter-packet delay for each period for the flow data FD of the predetermined flow Id, Update processing of “baseline data BLD” having “second delay amount” that is an average value of one delay amount as data content is performed.

Further, the data processing unit 313 estimates the communication state of each flow Id by comparing the first delay amount and the second delay amount, and performs priority update processing in the flow mapping table FMT based on this.
Note that the relay processing unit 310 uses the priority of the flow mapping table FMT updated by the data processing unit 313 to determine the priority for the transmission packet.

[Details of processing]
FIG. 3 is a schematic flowchart showing a processing procedure of the packet processor 309.
Hereinafter, specific processing contents performed by the processing units 311 to 313 of the processor 309 will be described with reference to FIG. 3 and subsequent FIGS. 4 to 12.
As shown in FIG. 3, the processor 309 of the router 3 captures a packet (step S1), extracts a header (step S2), classifies and generates data (step S3) for the received packet received by each transmitting / receiving unit. ) And data processing (S4) in this order.

<Packet capture>
Among these, packet capture (step S1) is processing performed by the capture processing unit 311 as described above. The capture processing unit 311 sequentially captures a predetermined amount of received packets accumulated in the capture reception buffer 303.

<Extract header>
The header extraction (step S2) is a process performed by the classification processing unit 312.
As illustrated in FIG. 3, the classification processing unit 312 extracts necessary layer L2-L5 header information from each packet received from the capture processing unit 311.

<Data classification and generation>
Data classification and generation (S3) is processing performed by the classification processing unit 312.
As shown in FIG. 3, the classification processing unit 312 searches the rule table RT and the flow table FT using the extracted header information of the packet as a key, thereby causing flow data FD (unregistered data if no hit is found in the search). And the data FD is stored in the corresponding storage area of the data buffer 315.

FIG. 4 is a diagram illustrating an example of the rule table RT, and FIG. 5 is a diagram illustrating an example of the flow table FT.
As shown in FIG. 4, the rule table RT includes “rule” entries having numbers 1 to 256, for example, and each rule corresponds to the flow Id in FIG. 5. Each rule includes a plurality (eight in the illustrated example) of “sub-rules”, and “items” and their values (Values) can be defined in the sub-rules.

Therefore, the content of the packet corresponding to the number of each rule (flow Id) can be defined by appropriately setting the subrule items and values.
For example, in the example of FIG. 4, the value of “destIp” (destination IP address) is defined in subrule 1 of rule 1, the value of “srcIP” (source IP address) is defined in subrule 2, and “rule IP” is defined in subrule 3. The value of “destPort” (destination port number) is defined, and the value of “srcPort” (source port number) is defined in sub-rule 4.

Although not shown in FIG. 4, by defining a predetermined protocol and a command used in the protocol after sub-rule 5 of each rule, the “type” of the packet to be searched according to each rule (flow Id) is set. Can be defined.
As illustrated in FIG. 5, the flow table FT is a table in which processing content corresponding to the flow Id is defined. For example, in the example of FIG. 5, in the case of a packet with flow Id = 1, a process of “leaving the packet as flow data” is performed.

Further, when the flow Id = 2, a process of “degenerate” the packet is performed, and when the flow Id = 3, a process of “discarding” is performed.
The rule table RT and the flow table FT are set, for example, when the user of the router 3 transmits a packet including the item contents and setting values of the tables RT and FT to the router 3 from the IP terminal 4 on the LAN side. Can be done by.

  The “flow data FD” is, for example, data for specifying a history of a plurality of packets of the same type having the same transmission / reception node, which is necessary in the case of a flow analysis for checking a linkage of a series of packet flows. That means.

The classification processing unit 312 searches the rule table RT in order from the top, and determines which rule the header information extracted from each packet matches.
As a result, when there is a matched rule (= flow Id), the process to be performed for the flow Id is read from the flow table FT, and the read process is executed for the packet of the flow Id. Further, the classification processing unit 312 generates unregistered data when there is no matched rule (= flow Id).

FIG. 6 is a diagram illustrating a data structure of the flow data FD.
As shown in FIG. 6, the flow data FD has a data structure including the reception time of the captured packet and the flow Id of the packet. The order of these data is not limited to that shown in the figure.
As described above, the packet source, destination, and type are assigned to each flow Id by the rule table RT (FIG. 4), so that the flow Id can identify the packet source, destination, and type. Identification information.

<Data processing>
The data processing (S4) in FIG. 3 is processing performed by the data processing unit 313.
As described above, the process performed by the data processing unit 313 includes the following processes, which will be described in detail later.
a) Update process of flow statistics data b) Update process of baseline data c) Update process of priority

[Example of flow data]
FIG. 7 is an example of a series of flow data FD in the same direction and its sequence diagram.
In the example of FIG. 7A, it is assumed that the packet with the flow Id = 1 is an RTP (Real-time Transport Protocol) packet transmitted by multicast.
As shown in FIG. 7A, the time interval between the flow data FDs of the flow Id = 1 is constant (20 μsec) while the time stamp value is 100 to 160 μsec. The time interval is greatly delayed. Therefore, in this case, it can be estimated that communication from the server is congested.

FIG. 8 is an example of a series of flow data FD bidirectionally and its sequence diagram.
In the example of FIG. 8A, it is assumed that the packet with the flow Id = 2 is an ICMP packet echo request and the packet with the flow Id = 3 is an echo response of the ICMP packet.
As shown in FIG. 8A, the time interval between the echo request of the flow Id = 2 and the echo response of the flow Id = 3 is constant (20 μsec) while the time stamp value is 100 to 220 μsec. However, no echo response comes after 300 μs. Therefore, in this case, it can be estimated that the server communication is disconnected for some reason in the time zone around 300 μsec.

[Flow mapping table]
FIG. 9 is a diagram illustrating an example of the flow mapping table FMT.
The definition items of the flow mapping table FMT include a flow Id, “srcIp”, “srcPort”, “destIP”, “destPort”, and “Timestamp” (reception time) that are address information and port information of the flow Id. QoS “priority”.
Therefore, the relay processing unit 310 can determine the priorities H and L to be applied to the transmission packet by searching the flow mapping table FMT using the address information and port information of the transmission packet as keys.

FIG. 10 is a diagram illustrating a data structure of the flow statistical data FSD and the baseline data BLD. As shown in FIG. 10A, the entry of the flow statistical data FSD includes “first flow Id” and “second flow Id” and first to nth “period”.
As described above, the “period” is a unit time of a predetermined time length (for example, 10 seconds) for collecting packets, which is necessary for calculating the average value of the delay between packets. Each period stores an average value AVG (i) (i = 1, 2,..., N) of inter-packet delays of packets having a flow Id value collected during the period.

As shown in FIG. 10B, the entry of the baseline data BLD includes “first flow Id” and “second flow Id” and an average value AVGbs. This average value AVGbs is an average value of a plurality of values randomly extracted from a plurality of average values AVG (i) (i = 1, 2,... N).
As described above, in this specification, the average value AVG (i) included in the flow statistical data FSD is referred to as “first delay amount”, and the average value AVGbs included in the baseline data BLD is referred to as “second delay amount”. "

[Flow statistics data update processing]
11 and 12 are flowcharts showing the update processing of the flow statistical data FSD.
As shown in FIG. 11, the data processing unit 313 first extracts address information and port information from the captured packet (step S11), searches the flow mapping table FMT (step S12), and matches the information. It is determined whether or not there is an entry (flow Id) to be performed (step S13).

As a result of the determination, if there is a matching flow Id, the data processing unit 313 acquires the flow Id and updates the time stamp of the flow mapping table FMT to the current time (step S14).
If there is no matching flow Id, the data processing unit 313 creates a new entry in the flow mapping table FMT (step S15).

The data processing unit 313 continues the above processing until the current period (i) ends (step S16). When the current period (i) ends, the data processing unit 313 increments the period by one (step S17). 12 and the processes after step 13 are performed.
Referring to FIG. 12, data processing unit 313 refers to the first entry (first flow Id) of flow statistical data FSD (step S18), and whether first flow Id and second flow Id have the same value. It is determined whether or not (step S19).

Here, in the flow statistical data FSD, when the first flow Id and the second flow Id have the same value, the same kind of packets (for example, the same type of packets that are continuously transmitted from one node to the other node (for example, FIG. 7).
Further, in the flow statistical data FSD, when the first flow Id and the second flow Id have different values, the flow is a request packet from one node to the other and a response packet (for example, FIG. 8).

As a result of the determination, if the values of the first flow Id and the second flow Id are the same, the data processing unit 313 collects the flow data FD that matches the value of the flow Id in chronological order (step S20). A difference value ΔT (j) of time stamps (reception times) between the flow data FD is sequentially calculated and collected (step S21).
Then, the data processing unit 313 divides the total of the collected difference values ΔT (j) by the number N of packets of the flow data FD that match the value of the flow Id (= AVG (i): first delay value) ) And the average value is input to the corresponding period of the flow statistical data FSD (step S22).

As a result of the determination, if the values of the first flow Id and the second flow Id are different, the data processing unit 313 collects the flow data FD that matches the value of the first flow Id in chronological order (step S23). ), The flow data FD that matches the value of the second flow Id is collected in the oldest order (step S24).
The data processing unit 313 also calculates a difference value ΔT (k) between the time stamp value of the flow data FD that matches the value of the first flow Id and the time stamp value of the flow data FD that matches the value of the second flow Id. Are sequentially calculated and collected (step S25).

  Then, the data processing unit 313 divides the total of the collected ΔT (k) by the number N of packets of the flow data FD that matches the value of the first flow Id (= AVG (i): first delay value) ) And the average value is input to the corresponding period of the flow statistical data FSD (step S26). In this case, it is assumed that the number of packets matching the value of the first flow Id and the number of packets matching the value of the second flow ID are the same in the flow data FD.

[Update processing of baseline data]
When newly creating the baseline data BLD, the data processing unit 313 randomly selects a plurality of values from a plurality of periods of the flow statistical data FSD, and averages the values (AVGbs: second delay amount). ) And is input to the corresponding entry of the baseline data BLD.

In addition, the data processing unit 313 performs an AVGbs update process using the learning coefficient α at the end of each period.
That is, if the difference between the newly added period AVG (i) and the AVGbs of the baseline data BLD already found exceeds a predetermined threshold, the data processing unit 313 sets the value of the learning coefficient α. When “0” is equal to or less than the threshold value, the value of α is set to v (where v is a set value satisfying 0 <v <1), and the value of AVGbs is updated by the following equation.
AVGbs = (1−α) × AVGbs + α × AVG (i)

[QoS priority update process]
Further, the data processing unit 313 performs priority update processing in the flow mapping table FMT at the end of each period by the following procedure.
That is, the data processing unit 313 first compares the period value AVG (i) of each entry of the flow statistical data FSD with the average value AVGbs of the same entry of the baseline data BLD at that time.

At this time, if AVG (i) is larger than AVGbs and the difference exceeds a predetermined threshold, the data processing unit 313 sets the priority of the corresponding flow Id in the flow mapping table FMT to “high”. To.
Conversely, when AVG (i) is smaller than AVGbs, or when AVG (i) is larger than AVGbs but the difference is within a predetermined threshold, the data processing unit 313 corresponds to the flow mapping table FMT. The priority of the flow Id is set to “low”.

  Thus, the AVGbs (second delay amount) of the baseline data BLD is the amount of delay that normally occurs in the packet of the flow Id when the AVG (i) (first delay amount) of each period in the flow statistical data FSD. Used as “reference delay amount” for determining whether or not.

[Effect of router]
As described above, according to the router (priority setting device) 3 of the present embodiment, the capture processing unit 311 acquires a plurality of packets having the same transmission / reception node, and the data processing unit 313 has a normal inter-packet delay. If the flow is larger than the current level, the priority is set higher than the current level, and the quality is lowered if the interpacket delay is lower than usual. Therefore, the priority can be flexibly changed according to the state of the network.

[Other variations]
In the above-described embodiment, the present invention is applied to the router 3 which is a device different from the line termination device (ONU 2 in FIG. 1). However, in the case of a home gateway in which the line termination device and the router 3 are integrated. The present invention may be applied to this apparatus.
Further, the first delay amount for each period of the flow statistical data FSD and the second delay amount of the baseline data BLD may be statistical amounts other than the average value such as a median value, for example.

In addition, the “reference delay amount” in the normal state for determining the amount of the first delay amount may be set to a fixed value instead of a plurality of first delay amount statistics (second delay amount). Good.
Furthermore, in the above-described embodiment, the local area networks LAN1 and LAN2 are configured by the Ethernet cable 9 as shown in FIG. 1. However, the router 3 is provided with an interface corresponding to the wireless LAN and communicates with the IP terminal 4 on the local area. May be performed wirelessly.
In this case, the contention window size may be set smaller for packets in the high priority queue than for packets in the low priority queue.

In the above-described embodiment, the case where the priority setting function of the present invention is implemented in the router 3 is illustrated, but the function may be implemented in the IP terminal 4 connected to the local networks LAN1 and LAN2.
In this case, if the priority of QoS determined dynamically by the IP terminal 4 is set to the router 3 by, for example, manual input or online access using SNMP, UPnP, or the like. Good.

  The embodiment disclosed this time (including the above-described modifications) is illustrative in all respects and not restrictive. The scope of the right of the present invention is not the embodiment described above, but includes all modifications within the scope equivalent to the scope of the claims.

3 router (priority setting device)
4 IP terminal 309 packet processor 310 relay processing unit 311 capture processing unit (acquisition unit)
312 Classification processing unit 313 Data processing unit (setting unit, calculation unit)
FD flow data FSD flow statistics data BLD baseline data

Claims (5)

A priority setting device that automatically sets the priority used for packet communication of the priority control method,
An acquisition unit for acquiring a plurality of packets having the same transmission / reception node;
A setting unit that sets the priority of the packet according to the inter-packet delay of the plurality of acquired packets;
Based on the acquisition times of the plurality of packets acquired in a predetermined period, a first delay amount that is a statistical amount of the inter-packet delay is calculated, and the first delay amount statistics calculated for each of the plurality of periods A second delay amount that is a quantity, and a calculation unit that employs the calculated second delay amount as a reference delay amount,
The setting unit is configured to set the priority of the packet based on a difference between the calculated first delay amount and the reference delay amount . The calculating unit, for the first delay amount difference is not less than a predetermined threshold and the reference amount of delay, priority setting device according to exclude claims 1 to calculate the elements of the second delay amount. The inter-packet delay, priority setting device according to claim 1 or 2 which is the time difference between the packet of the same kind are continuously transmitted from one node to the other node. 3. The priority setting apparatus according to claim 1, wherein the inter-packet delay is a time difference between a request packet from one node to the other and a response packet corresponding to the request packet. A computer program for causing a communication device capable of packet communication to function as a device for setting a priority used for packet communication of a priority control method,
A first step of acquiring a plurality of packets having the same transmitting / receiving node;
A second step of setting the priority of the packet according to the inter-packet delay of the plurality of acquired packets;
A third step of calculating a first delay amount, which is a statistical amount of the inter-packet delay, based on the acquisition times of the plurality of packets acquired in a predetermined period;
A fourth step of calculating a second delay amount that is a statistic amount of the first delay amount calculated for each of the plurality of periods, and adopting the calculated second delay amount as a reference delay amount;
In the second step, the priority of the packet is set based on the difference between the calculated first delay amount and the reference delay amount .