JPH11215153A - Congestion control type data transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a system that is operable even in a large-scale network with regard to a network change without largely changing a unitary management system by having a data transmission control means decide a condition of data transmission on the basis of an update job ticket. SOLUTION: A variable addition means 302 adds a variable to a job ticket that is sent to a data transmission control means 301 in accordance with data transmission situation in a transmission medium. When the transmission control means 31 receives the variable and the job ticket added by the variable addition means 302, it performs update of the job ticket on the basis of newer information, decides a transmission condition on the basis of the updated job ticket and outputs it to a transmission means as a transmission instruction. That is, when the variable added by the parameter addition means 302 is based on the information newer than the job ticket, the job ticket is updated anew by the variable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a congestion control type data transmission system for controlling contention occurring between data transmissions when a plurality of terminals transmit data at an arbitrary time on a shared network.

[0002]

2. Description of the Related Art In an environment where a plurality of data transmission terminals exist on the same data transmission network, when a plurality of terminals perform data transmission at an arbitrary time, transmission band competition occurs between the respective data transmissions.

[0003] A data transmission network generally comprises a plurality of transmission media. Generally, a plurality of terminals are connected to a network as data transmission terminals or data reception terminals, and data transmission is performed between the data transmission / reception terminals via a transmission medium constituting the network.

[0004] The transmission band of a transmission medium is represented by the amount of transmission data per unit time. The transmission capacity of the transmission medium is limited, and its maximum transmission band Rmax is a fixed and finite value.

[0005] The data transmission band of the transmission medium can be shared by a plurality of data transmissions, and each data transmission uses a band according to the amount of transmission data per unit time. The bandwidth usage r (t) of each data transmission changes every moment.

[0006] Data transmission sharing a band possessed by the same transmission medium When the sum 使用 r (t) of individual band usage amounts r (t) is larger than the maximum transmission band Rmax of the transmission medium, that is, Σr (t)> Rmax In the case of, the shared band competes for each data transmission. This is called a conflict.

[0007] Such contention reduces the efficiency of use of the band, and is desired to be avoided. In other words, if the band required for transmission cannot be obtained due to band contention,
That much data is lost.

In general, when data is lost, the lost data is retransmitted. By this, the effective band utilization efficiency, ie, [the amount of data successfully transmitted per unit time / the transmission Bandwidth used] decreases.

In order to suppress contention in the data transmission medium and efficiently utilize the maximum transmission band of the limited transmission medium, the transmission end of the data transmission uses a band R ( It is necessary to control t) and the band r (t) used by the transmission equally.

Japanese Patent Application Laid-Open No. 9-214555 discloses a conventional example dealing with the problem relating to contention. JP-A-9-214
No. 555 discloses a method for determining a detailed mode of data transmission from characteristic information of data transmission and information of a data transmission medium, and performing transmission based on the determined mode. A data transmission technique capable of obtaining accurate data transmission time prediction accuracy is disclosed.

FIG. 1 is a block diagram of a conventional contention avoidance type data transmission system. As shown in FIG. 1, the data transmission system includes a data transmitting unit 101, a data receiving unit 1
02, and data transmission control means 103. Each means is communicably connected by a data transmission medium. Although only one data transmitting means and one data receiving means are shown in FIG. 1, a plurality of data transmitting means and data receiving means are connected to a communication network constituting the system. A data transmission request is made from the plurality of data transmission means at an arbitrary timing.

In this data transmission system, when data transmission is performed from the data transmission means 101, first, a job ticket is transmitted to the data transmission control means 103 prior to data transmission. The job ticket records the data amount of data to be transmitted, the scheduled time of completion of data transmission, and the like. Upon receiving the job ticket, the data transmission control unit 103 generates a transmission instruction for achieving the data transmission requested by the job ticket based on the received job ticket and the data transmission being performed via the data transmission medium, and Is transmitted to the data transmission means 101.

The data transmission means 101 starts data transmission based on the transmission instruction received from the data transmission control means 103. In the transmission instruction, the band used for data transmission and the data transmission start time are recorded.
The data transmission unit 101 executes data transmission according to the data transmission instruction.

Although not shown in the figure, the data receiving means 102 receives the job ticket, which is a transmission request from the data transmitting means 101, and transmits the contents of the job ticket to the data transmission control means 103. It is also possible to adopt a configuration in which the data transmission control means 103 determines the mode of data transmission based on the job ticket from the data receiving means 102.

FIG. 2 is a block diagram showing the configuration of the data transmission control means 103. Data transmission control means 103 includes job ticket receiving means 201, data transmission instruction generation means 20
2. It has a data transmission instruction transmission unit 203, receives a job ticket from the data transmission unit 101 by the job ticket reception unit 201, and generates a data transmission instruction in the data transmission instruction generation unit 202 based on the received job ticket. The generated transmission instruction is transmitted to the data transmission unit 101 via the data transmission instruction transmission unit 203.

[0016]

However, according to the technique disclosed in Japanese Patent Application Laid-Open No. 9-214555, the current band utilization status is statically and unitarily managed by the data transmission control means. If there is a change in a network resource that is not directly managed by the means, an error occurs between the use state of the band recognized by the data transmission control means and the actual use state of the band.

For example, when a new competition point occurs on the transmission path between the data transmitting means and the data receiving means, the data transmission control means for determining the mode of data transmission has no way of knowing it. Assuming that there is no contention point, the transmission mode is determined and an instruction is given to the data transmitting apparatus. Specifically, the available bandwidth of the contention point, which was 100 Mbps before, is actually 50 Mbps, which is １ ／.
Even if the bandwidth is 100M
bps. As a result, competition occurs at a new competition point, and the transmission efficiency is greatly reduced due to cell / packet loss.

Further, in the technique described in Japanese Patent Application Laid-Open No. 9-214555, it is necessary to collectively manage information on the entire data transmission medium and characteristic information of each data transmission in one place in order to perform unified management. Therefore, every time there is a change in the data transmission medium (network), for example, the addition of a new client or server, the connection between networks, or the disconnection and connection or route change of the terminal due to the failure of the terminal or communication path, the management information Need to be changed.

The unified management method is practical for a relatively small network (a home or a small office having about 10 terminals), but is generally used for several tens to several thousand devices. It is practically inoperable in offices with terminals and lacks scalability.

Further, since a single medium is premised, when a plurality of services share a transmission medium, a plurality of different services must be unified, and a plurality of services required from the beginning are required. A centralized management means capable of handling services is required, and it is impossible to introduce services step by step, so that scalability is lacking in this sense.

An object of the present invention is to solve the problem described in JP-A-9-214555.
To enable operation in a large-scale network against network changes without significantly changing the unified management method proposed in the Japanese Patent Publication, and to provide scalability so that service can be gradually expanded It is.

[0022]

In order to solve the above-mentioned problems, a congestion control type data transmission system according to the present invention comprises a data transmitting means, a data receiving means, and transmitting data from the data transmitting means to the data receiving means. Data transmission system having a data transmission medium for performing data transmission control based on a job ticket including transmission information relating to the data transmission generated prior to data transmission from the data transmission means to the data reception means. Means for transmitting data from the data transmitting means to the data receiving means in accordance with the mode of data transmission determined by the data transmission control means. Job ticket to add data to
A data adding unit, and a job ticket updating unit that receives the job ticket changed by the job ticket / data adding unit, evaluates the received job ticket, and generates an updated job ticket used to determine a mode of data transmission. Wherein the data transmission control means has a configuration for determining a mode of data transmission based on the updated job ticket.

Further, in the congestion control type data transmission system of the present invention, the data in the job ticket which is changed or added by the job ticket / data adding means is another data transmission determined based on another job ticket. The data is calculated based on the aspect.

Further, in the congestion control type data transmission system according to the present invention, the data based on the data transmission mode relating to another job ticket is data calculated based on competition of data transmission bands in the data transmission medium. Features.

Further, in the congestion control type data transmission system according to the present invention, the data based on the mode of data transmission relating to another job ticket is data calculated based on the throughput of the data transmitting means or the data receiving means. Features.

Further, in the congestion control type data transmission system of the present invention, the job ticket / data adding means
It is provided at a position where a conflict occurs in data transmission via the data transmission medium.

Further, in the congestion control type data transmission system of the present invention, the job ticket updating means is arranged in the data transmission control means.

Further, in the congestion control type data transmission system according to the present invention, the content of data for adding or changing data to the job ticket by the job ticket / data adding means is a variable included in the job ticket. The generation of the updated job ticket by the ticket updating means is to determine the value of a variable.

Further, the congestion control type data transmission system according to the present invention is characterized in that, when a variable included in a job ticket is changed or updated, a notification is sent to a node that generated the variable.

Further, in the congestion control type data transmission system of the present invention, variables included in the job ticket include:
The node identifier of the node that generated the variable is added.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention has data transmission means and data reception means connected to a network for transmitting and receiving data via a network, and forms data transmission between these data transmission / reception devices. And data addition control means for determining or controlling the data transmission. Each component of the congestion control type data transmission system of the present invention will be described.

The data transmission means issues a job ticket prior to data transmission, and transmits the data to the transmission medium in accordance with the transmission mode specified by the data transmission control means for determining the transmission mode, for example, the specified transmission band. Send. The data receiving means receives data from the data transmitting means via a transmission medium. The data transmission control means for determining the transmission mode determines the transmission mode from the available bandwidth of the transmission medium and the contents of the job ticket.

The variable adding means functions as a job ticket data adding means for adding a variable to the job ticket and managing the variable. The variable adding means may exist at any position on the network. For example, on the data transmission means, means for adding information on data transmission available time as a variable, on the network, network resources,
For example, it is possible to provide a means for adding information on the bandwidth of the transmission path as a variable, and a means for adding information on data receivable time as a variable to the data receiving means. Further, a plurality of these variable adding means may exist.

FIG. 3 shows a network configuration example of the data transmission control means 301 and the variable load means 302 in the congestion control type data transmission system of the present invention. It is assumed that data transmission means and data reception means (not shown) are connected to the network.

The data transmission control means 301 receives a job ticket issued prior to data transmission from a data transmission means or a data reception means connected to a network. As described above, the job ticket records the data amount of the data to be transmitted, the scheduled completion time of the data transmission, and the like. Upon receiving the job ticket, the data transmission control unit 301 generates a transmission instruction for achieving the data transmission requested by the job ticket based on the received job ticket and the data transmission being performed via the data transmission medium, and Is transmitted to the data transmission means. This basic configuration is the same as the conventional configuration.

The congestion control type data transmission system of the present invention has a variable adding means 302. Variable addition means 3
02 adds a variable to the job ticket sent to the data transmission control unit 301 according to the data transmission status in the transmission medium. When receiving the variable added by the variable adding unit 302 and the job ticket, the data transmission control unit 301 updates the job ticket based on newer information, and determines the mode of transmission based on the updated job ticket. It is determined and output to the transmission means as a transmission instruction. In other words, if the variable added by the variable adding unit 302 is based on information newer than the job ticket, the job ticket is newly updated with the variable, and the data transmission control unit 301 The transmission mode is determined based on the ticket.

As shown in FIG. 3, the variable adding means 302
FIG. 3 has the free bandwidth information of the transmission medium, and adds a variable to the job ticket based on the free bandwidth information.
Execute the addition of the expression shown in.

The formulas are added or updated so as to prevent contention and congestion of data transmission between different jobs. The expression contains any variables. The addition or update of the formula can be performed at any place where the information on the transmission status of the data transmission medium can be received, and the independent variable adding means 302 may be configured as shown in FIG. Variable adding means 301 in transmission control means 301
You may comprise so that it may have.

That is, the variable adding means 301 for adding job ticket data is provided at a position where a conflict occurs in data transmission via the data transmission medium, and always grasps the conflict information of the conflict point and reflects the information. It is configured to add an expression, which is job ticket data, based on the obtained data. Alternatively, the data transmission control means may receive the information on the conflict points, and may change or add the formulas and variables in the job ticket based on the received data. Such a variable adding unit can be configured as an arbitrary node, that is, a data transmitting unit, a data receiving unit, a data transmission controlling unit, or an independent variable adding unit.

The data to be added or changed in the job ticket by the job ticket / data adding unit constituted by the variable adding unit 301 is, for example, a variable included in the job ticket.

There are various types of variables. For example, there is one that defines a band and a band available period.
As a portable form that uses a combination of an available bandwidth value, a data transmission start time, and a data transmission end time as data,
(100 MB, 1, 10) or (50 MB, 1
0,15). Evaluations on these equations are performed in the data transmission controller. The evaluation is performed in consideration of the result of executing the assignment based on the job ticket to be punched, determining the transmission mode and outputting the transmission instruction. In other words, a transmission mode based on a new job ticket is determined so as not to cause a conflict with the previously determined transmission instruction or to cause congestion.

When the data transmission control means 301 receives the job ticket or the job ticket to which the formula is added by the variable adding means 302, the data transmission control means 301 uses the received job ticket as it is for determining the mode of transmission, or It is determined whether the ticket is rewritten and the transmission mode is determined based on the rewritten job ticket. These operations evaluate the expression as
The process involves selecting the latest data, that is, selecting the latest data from the job ticket or the added expression.

The transmission control means 301 determines the competition status of the transmission medium due to data transmission executed based on various variables as network information, for example, a transmission instruction already instructed determined based on the preceding job ticket. I have it as information. For example, based on a transmission instruction from the data transmission control unit, data transmission from a certain transmission unit has information such as starting from time 100 and ending at time 110 as network information, and holds this information. In this state, if a job ticket based on a new data transmission request from another transmission unit is received, the transmission mode is determined and transmitted so that contention with these already instructed data transmissions does not occur. Make instructions.

The job ticket for determining the mode of transmission is an updated job ticket in which the variables in the job ticket have been updated to the final values. The generation of the updated job ticket is based on the variables in the original job ticket. , Variable adding means 3
01, that is, based on both variables added or changed by the job ticket / data adding means. When a variable is changed or updated, a notification may be sent to a node such as a data transmitting device or a receiving device or a variable adding unit that has generated the variable, and the change may be confirmed. By adopting the configuration, it is possible to confirm whether or not it is possible to determine the mode of data transmission allowed in each node. To enable such change notification, the job ticket variables include
The node identifier of the node that generated the variable is added correspondingly, and the notification is executed based on this identifier.

When a job ticket, which is a transmission request sent in advance of data transmission, passes through a conflict point, an expression indicating the conflict point information is added to the job ticket, and the expression is evaluated by the data transmission control means, thereby causing a conflict. Information on the point, for example, the usage status of the transmission band can be transmitted to the data transmission control means.

As a specific example, an expression indicating information on a conflict point is given by the following expression. The maximum transmission bandwidth at the contention point−the currently used bandwidth−the bandwidth allocated to the job> 0.

In the above equation, for example, assuming that the maximum transmission bandwidth = 100 Mbps and the currently used bandwidth = 40 Mbps are assigned as the respective values, the above equation is calculated by the data transmission control means and assigned to the job. The bandwidth to be used is 60 Mbps or less.

With such a configuration, even when a change is made to the network and the number of conflict points increases, the data transmission control means is not changed, and only the expression added to the job ticket is changed, and a new conflict point is changed. Contention can be avoided and efficient transmission can be performed.

[0049]

[Embodiment 1] An embodiment of a congestion control type data transmission system according to the present invention will be described. FIG. 4 shows the configuration of this embodiment. In this embodiment, as shown in FIG. 4, one data transmitting device 401, two first and second data receiving devices 402 and 403, and a data transmission control device 404 are connected to a network.

The configuration of the present embodiment shown in FIG. 4 has a simple configuration with a small number of transmission / reception devices for simplicity of description. However, in general, the data transmission control device and the data transmission device The plurality of data receiving apparatuses may have a configuration in which an arbitrary number of apparatuses are connected on a network.

Data transmission device 401 performs data transmission with data reception devices 402 and 403 via a transmission medium in accordance with a transmission mode determined based on a job ticket. Further, the data transmitting device 401 includes a variable adding unit that adds a variable to the job ticket.

The data transmission control device 404 receives a job ticket, which is a data transmission request from the data transmission device 401, and determines the mode of transmission in the data transmission control device 404 based on information included in the received job ticket. The determined transmission mode is transmitted to the data transmission device 401, and the data transmission device 401 executes data transmission according to the received transmission instruction.

Here, an operation in the case where one data transmitting apparatus 401 issues two job tickets requesting data transmission to two data receiving apparatuses 402 and 403 at the same time will be described.

First, the data transmission device 401 issues job tickets A and B for each data transmission to the two data reception devices 402 and 403, respectively. Here, it is assumed that the contents of the job tickets A and B have the following contents to simplify the description.

[Job ticket A]-Data size: 100 MBytes-Available transmission time: 100 to 120 [Job ticket B]-Data size: 150 MBytes-Available transmission time: 100 to 120

Each of the data receiving devices 402 and 403 receiving the job tickets A and B including the above contents, respectively.
Transfers the received job ticket to the data transmission control device 404.

Here, the job tickets A and B are transmitted from the data transmitting device 401 to the data receiving devices 402 and 403 once.
And then transferred from the data receiving devices 402 and 403 to the data transmission control device 404.
The information sent to 4 may not be the job ticket itself, but may be the information needed to determine the mode of transmission. Further, the job ticket may be directly transmitted from the data transmission device 401 to the data transmission control device 404. However, in that case, the data transmission control device 404
Must be able to interpret the job ticket, and information required by the data receiving devices 402 and 403 in the job ticket is transmitted from the data transmission control device 404 to the data receiving device 40.
Need to send to 2,403.

The two job tickets delivered to the data transmission control device 404 are processed in order. The job reception queue of the data transmission control device 404 is serialized to determine the processing order of two job tickets that have arrived at the same time.

Here, for the sake of convenience, the job ticket processed first is referred to as job ticket A, and the job ticket processed next is referred to as job ticket B.

The data transmission control device 404 first allocates a job to the job ticket A, that is, determines the mode of transmission. The data size of job ticket A is
As described above, the job ticket A is 100 MBytes, and the variable: the transmittable time is 100 to 120.
Regarding the data transmission, the transmission mode is determined so that transmission starts at time 100 in a 100 Mbps band.

At this time, the data transmission control device 404
The scheduled transmission end time of the data transmission for the job ticket A is calculated. Data transmission for job ticket A is 1
Since transmission starts at time 100 in the 00 Mbps band, the scheduled data transmission end time is time 108. The data transmission control device 404 changes the value of the transmission variable: transmittable time zone to 108 to 120 based on the scheduled data transmission end time for the job ticket A, and stores the value together with the changed time. This is for reference when generating a transmission instruction for another job ticket.

Next, a job is assigned to the job ticket B. The data size of the job ticket B is 150 Mbytes as described above, and the variable:
00 to 120. Where the variable: transmittable time is
It is stored in the data transmission control device 404 as described above. The data transmission control device 404 compares the job ticket B with the stored variable: time stamp of the transmittable time, and compares the variable of the old job ticket: transmittable time 10
The values of 0 to 120 are updated with new data 108 to 120.

The data transmission control device 404 sets the updated variables: the transmittable time 108 to 120 and the data size 150
The transmission mode to be instructed is determined from the MBytes. The transmission mode to be determined is as follows. [Transmission band:] 100 Mbps [Transmission start time:] 108

However, if transmission of 150 MBytes data is started at 100 Mbps from time 108 seconds, 12
Since it takes up to 0 seconds, the variable transmission available time is updated to NULL indicating that there is no transmission available time and stored together with the change time.

The transmission start time and the transmission band determined in this way are transmitted to the data transmission means 401 as the transmission mode for each job ticket.

Data transmitting means 40 having received the transmission mode
1 starts data transmission of the job ticket A at time 100 and then starts data transmission of the job ticket B at time 108 according to the contents.

FIG. 5 shows a configuration example of the data transmission control device 404.
Shown in The data transmission control device is a data transmission device 401.
A job ticket is received by the job ticket receiving unit 501 prior to data transmission from. For the received job ticket, the job ticket analysis unit 502 analyzes the amount of data recorded in the job ticket, the data transmittable time, and other conditions related to data transmission.

The information analyzed by the job ticket analysis unit 502 is transferred to the job allocation unit 503. The job allocating unit 503 has already determined the transmission mode, and uses the transmission medium usage status and the transmission medium usage schedule for the job that has output the transmission instruction from the variables stored in the variable storage unit 504, such as the above-described transmission available time and the like. Then, allocation is performed for the job for which a new transmission request has been issued. The assignment of the job is executed in consideration of an expression that defines data transmission recorded in the job ticket and various variables held in the variable holding unit. This processing will be described later in detail with reference to FIG. When the job assignment in the job assignment unit 503 is completed, the result is further transferred to the transmission mode determination unit 505, and conditions for data transmission, such as a transmission start time and a transmission band, are determined. The transmission mode determined by the transmission mode determination unit 505 is transmitted via the transmission instruction transmission unit 506 to the data transmitting apparatus 401 that is to start transmission.

FIG. 6 is a flowchart for updating the data of the job ticket executed in the job allocating unit. First, in step 601, the received job ticket is read, and in step 602, an expression included in the job ticket is extracted. For example, data size: 100 MBytes, possible transmission time: 100 to
120 and so on. Next, in step 603, variables in the expression of the job ticket are extracted. In the case of a job ticket, this is a variable: possible transmission time 100 to 120. Next, in step 604, it is determined whether or not the extracted variable has been registered in the variable holding unit (504 in FIG. 5). If not, registration is performed (step 605).
I do. When the registration is completed, or when the registration has already been performed, the process proceeds to step 606 to determine the value of the variable. In this determination, for example, if the variable to be determined is the transmittable time, as described above, the value of the variable is determined in consideration of the registered transmittable time and the timestamp of the transmittable time based on the new job ticket. Based on the variables determined in step 606, a new expression is
7 is calculated. In the above-described example, the values of the transmission variable: transmittable time slot are 108 to 120. The updated job ticket formula is transferred to the transmission mode determination unit 505 in FIG. 5, and the transmission mode determination unit 505 determines the transmission mode based on the updated job ticket. You.

A specific example of updating a job ticket will be described with reference to an example. Updating of the job ticket can be performed by, for example, a spreadsheet shown in FIG. The data transmission control means holds the spreadsheet shown in FIG. 7 and receives a job ticket from a data transmitting device or a data receiving device. In the example of FIG. 7, the job ticket requesting data transmission from the data transmission device 1 to the data reception device 2 includes a cell (A,
In 1), 50M is set as the band value. In the job ticket for requesting data transmission from the data transmitting device 2 to the data receiving device 2, the value of the band, 30M, is set in the cell (B, 2) as a variable. Upon receiving these two job tickets, the data transmission control unit determines that the variable to be updated is held in the corresponding cell in the variable holding unit, and it is determined by the time stamp comparison or the like that the data should be updated. Executes the update and determines the mode of transmission based on the updated data. ,

Also, instead of the above spreadsheet,
relational. It is possible to configure so that the expression is evaluated using a database (RDB). in this case,
The expression of the job ticket is described in a query language for the relational database. The evaluation and update of the expression are executed by an inquiry to the database, and the data, that is, the expression of the job ticket is updated by comparing the variable in the expression of the job ticket with the variable in the variable holding unit based on the inquiry.

[Second Embodiment] Next, the configuration of a second embodiment of the congestion control type data transmission system of the present invention will be described.
FIG. 8 shows the configuration of the second embodiment.

As shown in FIG. 8, the congestion control type data transmission system of the present embodiment has two data transmission devices 801 and 8
02 and two data receiving apparatuses 803, 804, and 1
It has a configuration in which one data transmission control device 805 is connected to a network. The network is divided by a transmission line 808 into two segments A and 806 and a segment B and 807.

Two data transmitting apparatuses 801 and 802 are connected to segments A and 806, and two data receiving apparatuses 803 and 804 are connected to segments B and 807, respectively.

Here, for the sake of simplicity, it is assumed that a sufficient band is always allocated to any data transmission in segment A, 806 and segment B, 807.

The bandwidth of the transmission line 808 connecting the segments A and 806 with the segments B and 807 is at least two.
There is not enough bandwidth to transmit two data at the same time,
In this embodiment, it is set to 100 Mbps.

The transmission path 808 adds a variable indicating information on the transmission path 808 to the job ticket that has passed through the transmission path 808. That is, the running path 808 is provided with a job ticket / data adding unit as a variable adding unit. In this embodiment, for the sake of simplicity, it is assumed that the use of the transmission line 808 allows only one data transmission at a time, and the transmission line state is defined as the idle time of the transmission line, that is, the available time. Variable.

The operation of this embodiment will be described. First, a first job ticket, which is a data transmission request, is issued from the data transmitting apparatuses 1 and 801 to the data receiving apparatuses 1 and 803.

The contents of the first job ticket issued from the data transmission apparatuses 1 and 801 are as follows: [Data size:] 100 MBytes.

The first job ticket having the above contents reaches the transmission line 808 through the segments A and 806.

In the transmission path 808, the current use information of the transmission path is added to the first job ticket assuming that [variable:] usable time of the transmission path = time 100-, and the job ticket is added to the data receiving device 1, 803. Transfer to

Next, a second job ticket, which is a data transmission request, is issued from the data transmitting devices 2 and 802 to the data receiving devices 2 and 804.

Here, two cases can be considered. One is that the first job ticket is sent before the second job ticket arrives on the transmission line.
Arrives at the data receiving device 1, 803,
When a variable in the job ticket is evaluated by the data transmission control device 805, and the result is transmitted to the transmission path 808. The other case is that the first job ticket has not been evaluated yet, and the result has not been transmitted to the transmission line 808.

First, in the former case, that is, before the second job ticket arrives at the transmission path, the first job ticket reaches the data receiving devices 1 and 803, and the data transmission control device 805 changes the variables in the job ticket. Evaluated
A case where the result is transmitted to the transmission path 808 will be described. The information of the first job ticket arriving at the data receiving apparatuses 1 and 803 is transmitted to the data transmission control apparatus 805. [Data size:] 100 MBytes [Variable “transmission line available time”:] Time 100 to

The data transmission control device 805 determines the mode of transmission based on the contents of the job ticket as follows. [Transmission bandwidth:] 100 Mbps [Transmission start time:] Time 100

Further, the value of the variable “transmission line available time” is updated, and the changed value is transmitted to the transmission line 808. As a result, the value of the variable “transmission line available time” of the transmission line 808 is as follows: transmission line available time = time 108.

At the same time, the data transmission control device 805
Are determined by the data transmission devices 1 and 8
01, the data transmitting apparatuses 1 and 801 start data transmission according to the instruction of the transmission mode.

Subsequently, the second job ticket from the data transmission devices 2 and 802 passes through the transmission path 808. At this time, the variable “transmission line available time” is added to the job ticket. The variable "transmission line available time" at this point
Is a value reflecting the result of the assignment of the first job ticket, that is, transmission line usable time = time 108 to.

The variable “transmission line available time” having this value
Arrives at the data transmission control device 805, the data transmission control device 805 compares it with the time stamp of its own variable “transmission line available time”. In this example, since both time stamps are changed when the first job ticket is assigned, they are the same time. Also, of course, the values are the same.

The data transmission control device 805 determines the mode of transmission based on the content of the job ticket as follows. [Transmission bandwidth:] 100 Mbps [Transmission start time:] Time 108

Further, the value of the variable “transmission line usable time” is updated, and the changed value is transmitted to the transmission line 808. As a result, the value of the variable “transmission line usable time” of the transmission line is as follows: transmission line usable time = time 116 to

At the same time, the data transmission mode is notified to the data transmission apparatuses 2 and 802, and the data transmission apparatuses 2 and 802 start data transmission in accordance with the transmission mode instruction.

Next, a description will be given of a process in a case where the evaluation of the first job ticket is not completed and the result is not transmitted to the transmission path 808, and the second job ticket passes through the transmission path 808. .

When the second job ticket passes through the transmission path, the transmission path 808 uses the current transmission path usage information as in the case of the first job ticket. The time is added to the second job ticket as time = time 100 to, and the job ticket is transferred to the data receiving apparatuses 2 and 804.

The second data arriving at the data receiving devices 2 and 804
[Data size:] 100 MBytes • [Variable “transmission line available time”:] Time 100 to are transmitted to the data transmission control device 805.

In the data transmission control device, two job tickets are sequentially received. In the processing after receipt of these two job tickets, the same processing as described in the first embodiment is executed.

Assuming that the job ticket transferred to the data transmission control device in advance is the first job ticket, the data transmission control device 805 first assigns a job to the first job ticket, that is, determines a transmission mode. Do. The transmission instruction for the first job ticket is as follows: [Transmission bandwidth:] 100 Mbps [Transmission start time:] Time 100

Further, the data transmission control device 805 calculates a scheduled end time of data transmission for the first job ticket. Data transmission for job ticket A is
Since transmission starts at time 100 in the 100 Mbps band, the scheduled data transmission end time is time 108
Becomes The data transmission control device 805 changes the value of the transmission variable: transmittable time zone to 108 or later based on the scheduled data transmission end time for the first job ticket, and stores the value together with the changed time. This is for reference when generating a transmission instruction for another job ticket.

Next, a job is assigned to the second job ticket. Here, the variable: transmittable time is stored in the data transmission control device 805. The data transmission control device 805 compares the second job ticket with the stored variable: the time stamp of the transmittable time, and compares the variable of the old job ticket: the transmittable time 100 to (the job added in the transmission path 808). The value of (ticket data) is updated with new data 108 to (variable stored when the processing of the first job ticket is completed in the data transmission control device).

The data transmission control device 508 determines the mode of transmission to be instructed based on the updated variable: possible transmission time 108-. The transmission mode to be determined is as follows. [Transmission band:] 100 Mbps [Transmission start time:] 108

Further, the value of the variable “transmission line usable time” is updated, and the changed value is transmitted to the transmission line 808. As a result, the value of the variable “transmission line usable time” of the transmission line is as follows: transmission line usable time = time 116 to

After receiving the variable “transmission line available time” of the new transmission line = time 116-, the transmission path 808
Is added to the new job ticket that passes through the transmission path available time = time 116-.

In the congestion control type data transmission system of the present invention, a job ticket / data addition means as a variable addition means is installed at a point where a contention may occur in a transmission medium, and information on the contention point is included in the job ticket. The data transmission control means can obtain more accurate transmission medium competition information based on the job ticket having the additional information and the information based on the previously processed job ticket. Is possible, and a more advanced transmission instruction is possible.

As described above, the job ticket / data adding means, which is a variable adding means, includes a data transmitting means,
It is also possible to configure by a data receiving means, a client device provided at a conflict point, or a gateway provided on a transmission medium, and when the job ticket passes these points, the latest variable information is included in the job ticket. With this addition, it is possible to determine the transmission mode by the data transmission control unit in a more reliable manner.

[0105]

As described above, according to the congestion control type data transmission system of the present invention, in a data communication system in which competition or congestion may occur, a new job ticket received by the data transmission control means is received. It is possible to use information reflecting the latest status of the data transmission medium when deciding the transmission mode for data transmission, and in an environment where transmission competition is likely to occur, a data transmission control system that enables more advanced congestion control Achieved.

Further, according to the congestion control type data transmission system of the present invention, it is possible to flexibly adapt to changes in network resources without making significant changes to data transmission control means, and to perform distributed management. This realizes a data transmission control system that enables centralized management even for a large-scale network.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating the flow of data at the start of data transmission in a conventional general data transmission system.

FIG. 2 is a configuration diagram showing a configuration of a general data transmission control unit.

FIG. 3 is a diagram showing a data flow from issuance of a job ticket prior to the start of data transmission to determination of a mode of transmission in the congestion control type data transmission system of the present invention.

FIG. 4 is a block diagram showing a configuration of a congestion control type data transmission system of the present invention.

FIG. 5 is a block diagram showing a configuration of a data transmission control device in the congestion control type data transmission system of the present invention.

FIG. 6 is a flowchart illustrating the evaluation of a job ticket expression in the congestion control type data transmission system according to the present invention.

FIG. 7 is a diagram showing an example of a spreadsheet used for re-evaluating a job ticket expression in the congestion control type data transmission system of the present invention.

FIG. 8 is a block diagram showing a second embodiment of the congestion control type data transmission system of the present invention.

[Explanation of symbols]

 301 Data transmission control unit 302 Variable addition unit 401 Data transmission device 402, 403 Data reception device 404 Data transmission control device 501 Job ticket reception unit 502 Job ticket analysis unit 503 Job allocation unit 504 Variable storage unit 505 Transmission mode determination unit 506 Transmission Instruction transmission unit 801 802 Data transmission device 803 804 Data reception device 805 Data transmission control device

Claims (9)

[Claims] 1. A data transmitting means, a data receiving means,
A data transmission system having a data transmission medium for transmitting data from the data transmission means to the data reception means, wherein transmission information on the data transmission generated prior to data transmission from the data transmission means to the data reception means is provided. Data transmission control means for determining a data transmission mode based on the included job ticket, and executing data transmission from the data transmission means to the data receiving means in accordance with the data transmission mode determined by the data transmission control means In the data transmission system having the configuration described above, a job ticket / data adding unit connected to the data transmission medium and adding data to the job ticket; and a job ticket to which data is added by the job ticket / data adding unit. Receiving, the receiving job A job ticket updating unit that evaluates a ticket and generates an updated job ticket used for determining the mode of the data transmission, wherein the data transmission control unit determines a mode of the data transmission based on the updated job ticket. A congestion control type data transmission system having a configuration for determining. 2. The job ticket data added by the job ticket data adding means is data calculated based on another data transmission mode determined based on another job ticket. The congestion control type data transmission system according to claim 1, wherein 3. The congestion according to claim 2, wherein the data based on the mode of data transmission regarding the other job ticket is data calculated based on competition of a data transmission band in the data transmission medium. Controlled data transmission system. 4. The congestion control according to claim 2, wherein the data based on the data transmission mode relating to the other job ticket is data calculated based on a throughput of a data transmission unit or a data reception unit. Type data transmission system. 5. The congestion control according to claim 1, wherein the job ticket / data adding unit is provided at a position where a contention occurs in data transmission via the data transmission medium. Type data transmission system. 6. The congestion control type data transmission system according to claim 1, wherein said job ticket updating means is arranged in said data transmission control means. 7. The content of data for adding or changing data to the job ticket by the job ticket / data adding means is a variable included in the job ticket, 7. The congestion control type data transmission system according to claim 1, wherein the generation determines the value of the variable. 8. The congestion control type data transmission system according to claim 7, wherein, when a variable included in the job ticket is changed or updated, a notification is sent to a node that generated the variable. 9. The congestion control type data transmission system according to claim 8, wherein a variable included in the job ticket is added with a node identifier of a node that generated the variable.