JP2005210301A - Sequence control program and method of packet transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sequence control program and method for extracting and transmitting data, having some degree of impartiality by imparting priority to buffers. <P>SOLUTION: The sequence control program includes information of packet extraction priority P(i), information of the degree of weighting summation WA(i), denoting the number of times of non-transmission of packets in spite of presence of packets, and information of a data quantity coefficient D(i), denoting the rate of the quantity of packets stored in the buffers by each of the buffers (i). It increments the WA(i) by one, when all the buffers have packets to be transmitted, sets 0 to the WA(i) when no packet exists, derives D(i) which represents the quantity of present packets B(i)× (quantity of buffers BS(i)) for all the buffers, derives an extract index K(i)= P(i)×WA(i)×D(i) for all the buffers, extracts and transmits packets from a buffer I whose K(i) is a maximum, sets 0 to the WA(I) of the buffer I, and repeats the above steps. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a packet transmission order control program and method that have a plurality of buffers that temporarily store packets to be transmitted, and that select the buffers to retrieve the next packet to be transmitted.

  The order control for transmitting packets is performed according to the order in which the communication program processes the packet transmission request and transmits it to the network in response to the packet transmission request from the application program. As an interface between both programs, there is a network API (Application Program Interface). This establishes a connection (communication path) with a counterpart communication node, and a typical example is a Socket interface. Data can be transmitted / received to / from the connection established here by normal read / write for file input / output.

  Such an interface has a buffer function for temporarily storing packets. In many cases, an OS (Operating System) scheduler determines which buffer packet is to be extracted and transmitted next. For example, even if a router is flow-controlled by a QoS (Quality of Service) function, it is a general control.

  However, when the order of extracting packets from the buffer is left to the OS scheduler, the following problems occur. First, even if the application writes packets to the buffer at regular intervals, the packets are only stored in the buffer and may not be transmitted on the line at regular intervals. Second, since an application that requires real-time processing and an application that does not need to be treated in the same manner, packets that should be prioritized may not be prioritized. Third, when there are a large number of buffers, the order in which the buffers are taken out cannot be specified. Fourth, there are routers that have a QoS function, but since they only perform operations that prioritize packet extraction based on preset information, they cannot be dynamically extracted according to packet type or packet waiting time. .

  Accordingly, an object of the present invention is to provide an order control program and method for extracting and transmitting data fairly fairly while giving priority to buffers in order to solve these problems.

According to the sequence control program of the present invention,
For each buffer i, information on the packet extraction priority P (i), information on the wait addition level WA (i) indicating the number of packets that have not been transmitted despite the presence of the packet, and packets accumulated in the buffer Data amount coefficient D (i) information indicating the proportion of the amount,
For all buffers, if there is a packet to be transmitted, the first step of incrementing the waiting addition degree WA (i) by 1;
A second step of deriving a data amount coefficient D (i) consisting of the current packet amount B (i) × buffer amount BS (i) for all buffers;
A third step of deriving an extraction index K (i) consisting of priority P (i) × waiting addition WA (i) × data amount coefficient D (i) for all buffers;
A fourth step of extracting and transmitting a packet from the buffer I having the maximum extraction index K;
And a fifth step of setting the wait addition degree WA (I) in the buffer I to 0, and the computer is executed so as to repeat the first to fifth steps.

  According to another embodiment of the sequence control program of the present invention, it is also preferably applied to a network API. Further, the network API may be a Socket interface.

According to the sequence control method of the present invention,
For each buffer i, information on the packet extraction priority P (i), information on the wait addition level WA (i) indicating the number of packets that have not been transmitted despite the presence of the packet, and packets accumulated in the buffer Data amount coefficient D (i) information indicating the proportion of the amount,
For all buffers, if there is a packet to be transmitted, the first step of incrementing the waiting addition degree WA (i) by 1;
A second step of deriving a data amount coefficient D (i) consisting of the current packet amount B (i) × buffer amount BS (i) for all buffers;
A third step of deriving an extraction index K (i) consisting of priority P (i) × waiting addition WA (i) × data amount coefficient D (i) for all buffers;
A fourth step of extracting and transmitting a packet from the buffer I having the maximum extraction index K;
And a fifth step of setting the waiting addition degree WA (I) in the buffer I to 0, and the first to fifth steps are repeated.

  According to the sequence control program and method of the present invention, data can be transmitted in accordance with the traffic characteristics of the data stored in each buffer. Further, the fairness between the buffers can be maintained by using the waiting addition degree WA and the data amount coefficient D, instead of simply taking out the data based on the priority of the buffer. In particular, since the waiting addition degree WA and the data amount coefficient D are constantly calculated, dynamic traffic control is possible.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a functional configuration diagram of a program in the present invention.

  According to FIG. 1, it includes an acquisition buffer selection unit 1, a data acquisition unit 2, and buffers 31 to 34. The acquisition buffer selection unit 1 selects a buffer for acquiring data to be transmitted next from among the plurality of buffers 31 to 34. The data acquisition unit 2 extracts data from the buffer determined by the acquisition buffer selection unit 1 and transmits it to the line side. The buffers 31 to 34 temporarily store data received from an upper layer via the Socket interface.

The acquisition buffer selection unit 1 holds a data acquisition management table shown in Table 1 below.

Buffer number i (= 1 to n): Identifier assigned to each buffer Priority P (i): Priority of data retrieval in buffer i Buffer size BS (i): Data storage capacity in buffer i Current buffer amount B (i): Data amount currently stored in buffer i Data amount coefficient D (i): Coefficient indicating the current data storage ratio in buffer i Waiting addition WA (i): Data exists in buffer i The number of times when the data was not taken out The taking index K (i): index indicating the degree of necessity for taking out in the buffer i

  FIG. 2 is a flowchart of the acquisition buffer selection unit in the present invention.

  The processing of this flowchart is started by a data extraction trigger.

First, the priority P (i) and the buffer size BS (i) are specified for all the buffers. Note that the higher the value of the priority P, the higher the necessity of transmitting a packet from the buffer.
(S201) The extraction index K (I) = 0 in the buffer number I of the maximum extraction index is set.
(S202) The processing up to S210 is performed for all the buffers i = 1 to n.
(S203) The data amount B (i) currently accumulated for the buffer i is acquired.
(S204) It is determined whether or not the current buffer amount B (i) is 0 for the buffer i.
(S205) If the current buffer amount B (i) is not 0, the waiting addition degree WA (i) is incremented by 1, and the data amount coefficient D is calculated.
D (i) = B (i) / BS (i)
(S206) When the current buffer amount B (i) is 0, the waiting addition degree WA (i) is set to 0, and the data amount coefficient D (i) is also set to 0.
(S207) The takeout index K (i) is calculated by multiplying the priority P (i), the waiting addition degree WA (i), and the data amount coefficient D (i).
K (i) = P (i) × WA (i) × D (i)
(S208) It is determined whether or not the extraction index K (i) in the buffer number i is larger than the extraction index K (I) in the buffer number I having the maximum extraction index.
(S209) If K (i) is larger than K (I), the buffer number I of the maximum extraction index is set to the buffer number i.
(S210) It repeats between S202 about all the buffers i = 1-n.
(S211) The data acquisition unit 2 is instructed to acquire data from the buffer number I. As a result, the data acquisition unit 2 acquires and transmits data from the buffer of the buffer number I.
(S212) The waiting addition degree WA (I) in the buffer number I of the maximum extraction index is set to zero.

  In the various embodiments of the present invention described above, various changes, modifications, and omissions in the scope of the technical idea and the viewpoint of the present invention can be easily made by those skilled in the art. The above description is merely an example, and is not intended to be restrictive. The invention is limited only as defined in the following claims and the equivalents thereto.

It is a function block diagram of the program in this invention. It is a flowchart of the acquisition buffer selection part in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Acquisition buffer selection part 2 Data acquisition part 31-34 Buffer

Claims (4)

In a sequence control program that has a plurality of buffers that temporarily store packets to be transmitted, and that causes the computer to function by selecting the buffers and extracting the packets to be transmitted next.
For each buffer i, information on the packet extraction priority P (i), information on the waiting addition level WA (i) indicating the number of times the packet was not transmitted despite the presence of the packet, and the buffer accumulated Data amount coefficient D (i) information indicating the ratio of the packet amount,
For all the buffers, a first step of incrementing the wait addition degree WA (i) by 1 if there is a packet to be transmitted and setting the wait addition degree WA (i) to 0 if there is no packet to be transmitted;
A second step of deriving a data amount coefficient D (i) consisting of the current packet amount B (i) × buffer amount BS (i) for all the buffers;
A third step of deriving an extraction index K (i) consisting of priority P (i) × wait addition degree WA (i) × data amount coefficient D (i) for all the buffers;
A fourth step of extracting and transmitting the packet from the buffer I having the maximum extraction index K;
And a fifth step of setting the wait addition degree WA (I) in the buffer I to 0, and causing the computer to repeat the first to fifth steps. program.   The sequence control program according to claim 1, which is applied to a network API.   The sequence control program according to claim 2, wherein the network API is a Socket interface. In a plurality of buffers temporarily storing packets to be transmitted, and an order control method for selecting the buffers and extracting packets to be transmitted next,
For each buffer i, information on the packet extraction priority P (i), information on the waiting addition level WA (i) indicating the number of times the packet was not transmitted despite the presence of the packet, and the buffer accumulated Data amount coefficient D (i) information indicating the ratio of the packet amount,
For all the buffers, a first step of incrementing the wait addition degree WA (i) by 1 if there is a packet to be transmitted and setting the wait addition degree WA (i) to 0 if there is no packet to be transmitted;
A second step of deriving a data amount coefficient D (i) consisting of the current packet amount B (i) × buffer amount BS (i) for all the buffers;
A third step of deriving an extraction index K (i) consisting of priority P (i) × wait addition degree WA (i) × data amount coefficient D (i) for all the buffers;
A fourth step of extracting and transmitting the packet from the buffer I having the maximum extraction index K;
And a fifth step of setting the waiting addition degree WA (I) in the buffer I to 0, and repeating the first to fifth steps.

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