JPH11145975A - Transmission control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission control system capable of scheduling with the delivery completion time as a reference in a transmission line incapable of guaranteeing delivery time like TCP(transfer control protocol)/IP(internet protocol) and 'Ethernet(R)' and realizing real time communication. SOLUTION: In the case of transmitting data exceeding a maximum data length allowed by a data link layer or scheduling processing, transmission data are divided refering to the maximum data length allowed by the data ink layer or the scheduling processing and a time critical division constitution header provided with information for division and reconstitution and the delivery completion time set to the data received from a high-order layer is imparted to the divided respective data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission method in a communication system for scheduling transmission among a plurality of nodes connected to a network and mutually transmitting data, based on a delivery time constraint between a transmission node and a reception node. Related to the control method.

[0002]

2. Description of the Related Art Conventionally, a control device in an industrial field has maintained its performance and safety by a unique communication system dedicated to a control system. However, TCP (Transport Control Protocol) or UDP (User Datagram Protocol)
/ IP (Internet Protocol) has become widespread as a de facto standard, and these de facto standards have permeated this industrial field. However, although TCP has a packet retransmission function, since it is on the order of seconds, it is not suitable for transferring control data. In Ethernet, frames that cannot be transmitted appear because of collision of frames. Therefore, it cannot be said that these de facto standards can always maintain the performance of the control system.

[0003]

Conventionally, it has not been possible to mix TCP / IP of the de facto standard and time-critical communication. However, the delivery completion time is added to the data here, and the data is transmitted to the destination by that time. (See, for example, Japanese Patent Laid-Open No. 6-6)
407, JP-A-6-152604, JP-A-8-32
623, JP-A-9-18510, and Japanese Patent Application No. 9-182.
699). According to this method, it is possible to deliver data such as control information for which the valid time is determined within the designated time, and it is possible to satisfy the requirements of the control system.

Therefore, there is a demand for a transmission control method for performing time-critical communication while utilizing TCP / IP processing.

[0005] The present invention has been made in view of the above,
An object of the present invention is to provide a transmission control method capable of performing scheduling based on a delivery completion time on a transmission path such as TCP / IP or Ethernet where delivery time cannot be guaranteed and realizing real-time communication. It is in.

[0006]

To achieve the above object, according to the present invention, there is provided a communication system for transmitting and receiving data between a plurality of nodes connected to a network and mutually transmitting data. In a communication method in which transmission scheduling is performed based on a delivery time constraint, when transmitting data exceeding the maximum data length permitted by the data link layer or the scheduling process, based on the maximum data length permitted by the data link layer or the scheduling process. The transmission data is divided, and each of the divided data is provided with information for division and reconstruction and a time-critical division configuration header having a delivery completion time set in data received from an upper layer. And

According to the first aspect of the present invention, data is divided on the basis of a maximum data length allowed by a data link layer or a scheduling process, and information for division / reconstruction is divided into each divided data. Since the time critical division configuration header including the delivery completion time is added, scheduling processing can be performed even on data that is too long.

[0008] The present invention according to claim 2 is based on claim 1.
In the described invention, after performing a scheduling process on the received data, reconfigure the data based on the information of the time critical division configuration header,
The point is to transmit the reconstructed data to the upper layer.

According to the second aspect of the present invention, after performing scheduling processing on received data, reconfiguration is performed.
The reconstructed data is transmitted to the upper layer.

Further, the present invention according to claim 3 provides the present invention as claimed in claim 2.
In the invention described above, if data reconstruction is not completed even after the delivery completion time of the time critical division configuration header, the data being reconstructed is discarded.

According to the third aspect of the present invention, if the reconstruction is not completed even at the delivery completion time, the data being reconstructed is discarded.

According to a fourth aspect of the present invention, there is provided a communication system for performing transmission scheduling between a plurality of nodes connected to a network and mutually transmitting data, based on a delivery time constraint between a transmission node and a reception node. The Internet Protocol (IP) header and the delivery completion time are used as an Internet Protocol pseudo-header, and the protocol to which the delivery completion time is added received from the application is time-critical (TC).
The gist of the present invention is to create an Internet protocol pseudo header using the normal Internet protocol header and the data delivery completion time of the data as the delivery completion time of the Internet protocol pseudo header, and perform the scheduling process.

According to the present invention, a normal Internet protocol in which the IP header and the delivery completion time are used as an IP pseudo-header, and the data to which the delivery completion time is added is a time critical (TC) protocol. Since the scheduling process is performed by creating an Internet protocol pseudo header using the delivery completion time of the header and its data as the delivery completion time of the Internet protocol pseudo header, it looks as if a normal IP packet is flowing on the transmission path, such as a router. And the scheduling process can be performed between nodes where the relay device exists.

The present invention described in claim 5 provides the present invention according to claim 4.
In the described invention, the total number of Internet protocol headers in the Internet protocol pseudo header is
The division is performed using the length (Total Length), the flag (Flag), and the fragment offset (Fragment Offset) as values for performing division based on the maximum data length allowed by the data link layer or the scheduling process. The gist of the present invention is to add an Internet protocol pseudo header to each data item.

According to the present invention, the total length (Total Length) of the IP header in the IP pseudo header is set.
Length), Flag (Flag) and Fragment Offset (Fragment Offset) are used as values when data is divided based on the data link layer or the maximum data length allowed by the scheduling process. Is given an IP pseudo-header.

Further, the present invention according to claim 6 provides the invention according to claim 5.
In the described invention, after performing a scheduling process on the received data, a total length (Total Length), a flag (Flag), and a fragment offset (Fragment Offset) of the Internet protocol header in the Internet protocol pseudo header are transmitted to the data link. The point is that reconfiguration is performed by regarding the value as the maximum data length allowed by the layer or the scheduling process.

According to the present invention, after scheduling the received data, the total length of the IP header in the IP pseudo header is calculated.
h), Flag and fragment offset
(Fragment Offset) is regarded as a value based on the maximum data length allowed by the data link layer or the scheduling process, and reconfiguration is performed.

According to a seventh aspect of the present invention, in the invention of the sixth aspect, if the reconfiguration is not completed even after the time indicated by the completion time of the delivery of the IP pseudo header, the data being reconfigured is discarded. The point is to do.

According to the present invention, if the reconfiguration is not completed by the time indicated by the delivery completion time of the IP pseudo header, the data being reconfigured is discarded.

The present invention described in claim 8 provides the present invention according to claim 4.
In the invention described in the above, a correspondence table that defines a spare time for delivery with respect to a type of service (Type of Service) value of the Internet protocol header is provided, and data with a delivery completion time is provided to a node across the relay device Is transmitted, the type of service (Type of Service) value is determined from the correspondence table, and the type of service (Type of Service) of the Internet protocol pseudo header is determined.
(Service).

According to the present invention, there is provided a correspondence table for defining a spare time for delivery with respect to the type of service (Type of Service) value of the IP header. When transmitting data with the time of completion of transmission, the value of Type of Service is determined from the correspondence table, and the type of service of the Internet protocol pseudo header is determined.
Service).

Further, according to the present invention, there is provided a communication system for performing transmission scheduling between a plurality of nodes which are connected to a network and mutually transmit data based on a delivery time constraint between a transmission node and a reception node. In the method, there is provided a correspondence table defining a delivery allowance time for a type of service (Type of Service) value of an Internet protocol header, and a delivery time in the correspondence table for the Internet protocol transmission request data at a current time. The gist is that the scheduling process is performed by regarding the time obtained by adding the extra time as the delivery completion time of the data.

According to the ninth aspect of the present invention, there is provided a correspondence table for defining a spare time for delivery with respect to the type of service (Type of Service) value of the IP header, and for the IP transmission request data. Since the scheduling process is performed by regarding the time obtained by adding the delivery allowance time in the correspondence table to the current time as the delivery completion time of the data, the type of service of the IP header of the normal IP packet to which the delivery completion time is not given If (Type of Service) indicates urgent, by giving a delivery completion time corresponding to this correspondence table, normal IP packets that need to be sent earlier can be sent earlier.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a time critical processing unit that performs time critical processing in a transmission control method according to an embodiment of the present invention. The time critical processing unit shown in FIG. 1 includes a time critical communication function execution unit 1, a TC (time critical) division processing unit 2, and a TC reconfiguration processing unit 3. The time critical communication function execution unit 1
Similarly to the time-critical communication function execution unit described in JP-A-182699, transmission is performed between a plurality of nodes connected to a network for mutually transmitting data based on a delivery time constraint between a transmission node and a reception node. It performs scheduling processing. When transmitting data exceeding the maximum data length permitted by the data link layer or the scheduling process, the TC division processing unit 2 divides the transmission data based on the data link layer or the maximum data length permitted by the scheduling process. The TC reconfiguration processing unit 3 is a module that reconfigures the divided data.

The data divided by the TC division processing unit 2 is as follows:
A TC division reconfiguration header 4 as shown in FIG. 2 is added. The TC division / reconstruction header 4 includes a division / reconstruction header 5 including a division number 10, a total number of divisions 11, a total data length 12, and a division unit length 13, a delivery completion time 6, a data identifier 7, and a transmission destination address 8. , And a transmission source address 9, which is assigned to upper layer data. Delivery completion time 6
Is the delivery completion time attached to the data received from the upper layer, and the time-critical communication function execution unit 1
The scheduling process is performed based on the delivery completion time 6 in the TC division reconfiguration header 4.

The TC division processing section 2 manages a data identifier management table 14 as shown in FIG. The data identifier management table 14 includes a data identifier 15, a delivery completion time 16 (the initial value is 0), an upper layer data identifier 17
(The initial value is 0) and the number of completions 18 (the initial value is 0).

Upon receiving the transmission request data from the upper layer, the TC division processing unit 2 searches for the data identifier 15 whose delivery completion time 16 is 0 (empty), and sends the ID number of the searched data identifier 15 to the transmission request. The data identifier 7 of the TC division reconfiguration header 4 added to the data is set. Also, the transmission completion time 16 of the corresponding ID in the data identifier management table 14 is set as the transmission completion time of the transmission request data, the upper layer data identifier 17 is set as the identification value assigned by the upper layer, and the number of completions 1
Let 8 be the number of data divisions.

The TC division processing unit 2 sets the maximum data length permitted by the data link layer or the scheduling process as a division unit length 13, the data length of data received from an upper layer as a total data length 12, and The quotient obtained by dividing 12 by the division unit length 13 (1 is added if there is a remainder, and is not rounded down) is defined as the total number of divisions 11, and is divided from the top of the upper layer data by the division unit length 13 as a unit. 1, 2, 3,.
A TC division reconfiguration header 4 is created by setting a number consecutive with... As the division number 10, and the TC division reconfiguration header 4 is added to each segmented data, and is passed to the time-critical communication function execution unit 1.

When the TC division processing unit 2 receives the notification of the completion of transmission together with the value of the TC division reconfiguration header 4 from the time critical communication function execution unit 1, the TC division processing unit 2 calculates the corresponding completion number 18 in the data identifier management table 14. When 1 is subtracted and the result is 0, the delivery completion time 16 is set to 0
(Empty) and notifies the upper layer of the delivery completion together with the upper layer data identifier 17.

When the TC division processing unit 2 receives the notification of non-delivery together with the value of the TC division reconfiguration header 4 from the time critical communication function execution unit 1, the corresponding transmission in the data identifier management table 14 is performed. Completion time 1
6 is checked to see if it matches the delivery completion time 6 in the TC segmentation reassembly header 4, and if they match, the delivery completion time 16 is set to 0 (empty) and the upper layer data identifier is sent to the upper layer. Notify with 17 that delivery is not possible.
If the delivery completion time 16 is 0 (empty), nothing is done.

The TC reconfiguration processing unit 3 reconfigures the divided data based on the reconfiguration management table 19, the number of data being reconfigured, and the earliest delivery completion time as shown in FIG.
The reconfiguration management table 19 shown in FIG. 4 includes a source address 20, a destination address 21, a data identifier 22, a delivery completion time 23, and a pointer 24 to reconfiguration information. The pointer 24 to the reconfiguration information indicates information necessary for the reconfiguration such as the total data length, the division unit length, the reception data start address, and the like. May be different.

When the TC reconfiguration processing unit 3 receives the received data from the time critical communication function executing unit 1, the total number of divisions 11 of the received data is 1,
If the delivery completion time 6 is later than the current time, the upper layer data is passed to the upper layer. If the total number of divisions 11 is greater than 1 and the delivery completion time 6 is later than the current time, the transmission source address 9, the transmission destination address 8, and the data identifier 7 in the TC division reconfiguration header 4 are reset. Source address 20 and destination address 2 in the configuration management table 19
1, a number (N
o. ) Is detected.

If there is no match in this detection, a number (No.) in which the source address 20 is 0 (empty) is searched for, and the source address 20 and the destination A source address 9, a destination address 8, a data identifier 7, and a delivery completion time 6 are set in the address 21, the data identifier 22, and the delivery completion time 23, respectively, and reconfiguration information is created, and a pointer 24 to the reconfiguration information is created. Is set, and 1 is added to the number of data being reconstructed.
Furthermore, the earliest delivery completion time is 0 (no timer setting)
If not, the earliest delivery completion time is compared with the delivery completion time 6, and if the delivery completion time 6 is closer to the current time, the delivery completion time 6 is set to the earliest delivery completion time. Set the timer to be interrupted at the delivery completion time. If the earliest delivery completion time is 0, the delivery completion time 6 is set to the earliest delivery completion time, and a timer interrupt is set to this delivery completion time.

Further, if the total number of divisions 11 of the data received by the TC reconfiguration processing unit 3 from the time critical communication function execution unit 1 is greater than 1 and the delivery completion time 6 is later than the current time, the TC division The source address 9, the destination address 8, and the data identifier 7 in the reconfiguration header 4 correspond to the source address 20, the
If there is a number (No.) that matches each of the transmission destination address 21 and the data identifier 22, the reconfiguration information is updated.

When the reconfiguration is completed, the source address 20 of the corresponding number (No.) in the reconfiguration management table 19 is set to 0, and the reconfigured upper layer data is passed to the upper layer.
Subtract 1 from the number of data being reconfigured and discard the reconfiguration information.

When a timer interrupt that reaches the delivery completion time set as described above is applied, a number (No.) in which the delivery completion time 23 in the reconfiguration management table 19 matches the earliest delivery completion time is set. All data are searched, the data under reconfiguration and the reconfiguration information are discarded, the source address is set to 0, and the number of times the source address is set to 0 is subtracted from the number of data being reconfigured. As a result, when the number of data being reconfigured is not 0, the time closest to the current time among the delivery completion times where the source address is not 0 is set as the earliest delivery completion time, and a timer interrupt is generated at that time. It is set so. If the number of data being reconfigured is 0, the earliest delivery completion time is 0 (no timer setting)
And

Next, a transmission control method using an IP header will be described as another embodiment of the present invention.
In the present embodiment, the TC division processing unit 2 shown in FIG.
The C reconstruction processing unit 3 divides and reconstructs data using an IP pseudo header format as shown in FIG. The IP pseudo header 30 shown in FIG. 5 includes an IP header 31 and a delivery completion time 32. I
The P header 31 is configured as shown in FIG.

The TC division processing unit 2 divides the transmission request data received from the upper layer based on the maximum data length allowed by the data link layer or the scheduling processing. The division method is the same as the IP processing. If necessary, the data is divided and the IP shown in FIG.
A pseudo header 30 is provided. The delivery completion time 32 of the IP pseudo header 30 is the delivery completion time attached to the upper layer data.

The IP header 3 of the IP pseudo header 30
1 is created as follows. Identification (Identification) and flag (Fl) of the IP header 31
ag), Fragment Offset
Is information for division / reconfiguration, and is created in the same way as normal IP processing, based on the maximum data length allowed by the data link layer or the scheduling processing. In addition,
Bit 1 of the flag (Flag) is set to 0 (may be divided). In addition, the time to live is set to 255 seconds at the maximum, the protocol is set to a value (TC) representing the communication system, and the source address (Source Addre) is set.
ss) and destination address (Destination A)
ddress) is the corresponding IP address. Version (V
ersion), IHL, Total Length
h), Header Checksum, Options, Padding are normal IP
The value is determined by processing.

Type of Service (Type of Service)
e) is a type of service (Type) as shown in FIG.
of Service) value and the table of available time for delivery. The delivery allowance time is the difference between the delivery completion time 32 indicated in the IP pseudo header 30 and the current time. In the correspondence table shown in FIG. 7, as an example, the type of service
vice) bit 1 is set to 1 (Low Delay) and bit 4 is set to 0
(Normal Throughput) and bit 5 is set to 0 (Normal Rel
iability) and bits 0 to 2 (Preceden
ce) is set to 7 when the delivery allowance time is less than the slot time * 5, 6 when the slot time is greater than or equal to 5 and less than 10, and 5 when the slot time * 10 or more.
Note that the slot time is a time unit in the scheduling process, and is a cycle at which scheduling is performed.

As described above, the TC division processing unit 2
The P pseudo header 30 is created, attached to the data, and passed to the time-critical communication function execution unit 1. For the transmission request data received from the upper layer, the division management table 33 as shown in FIG. 8 is also managed. As shown in FIG. 8, the division management table 33 stores the SA (source address: So
The information includes an urce address 34, a DA (destination address) 35, an identification 36, a delivery completion time 37, an upper layer data identifier 38, and a completion number 39. The TC division processing unit 2 searches the division management table 33 for a location where the delivery completion time 37 is 0 (empty), sets the source address (Source Address) of the IP header 31 in the searched SA 34, and sets the destination address in the DA 35. Set the Destination Address and set the IP address in the Identification 36
Identification of header 31 (Identifica
option).

Further, a delivery completion time 32 of the IP pseudo header 30 is set in the delivery completion time 37 (initial value 0),
The number of divisions is set as the number of completions 39, and the identification value assigned to the upper layer is set as the upper layer data identifier 38. The TC division processing unit 2 receives the IP from the time critical communication function execution unit 1
When the notification of the completion of the delivery is received together with the value of the pseudo header 30, the SA 34, DA in the division management table 33
35, Identification
When 1 is subtracted from the number of completions 39 where 36 matches, and the result is 0, the delivery completion time 37 is set to 0 (empty) and the delivery completion is notified to the upper layer together with the upper layer data identifier 38. .

Also, when the TC division processing unit 2 receives the notification of non-delivery together with the value of the IP pseudo header 30 from the time critical communication function execution unit 1, the SA 34, DA 35, identity If the delivery completion time 37 at which the identification (Identification) 36 matches the delivery completion time 32 in the IP pseudo header 30, the delivery completion time 37
Is set to 0 (empty), and the upper layer data identifier 38 is sent to the upper layer.
Notify with non-delivery. Delivery completion time 37 is 0
If it is (empty), do nothing.

The TC reconfiguration processing unit 3 reconfigures data according to the IP reconfiguration process, and monitors the time until the reconfiguration is completed by monitoring time to live.
, But the delivery completion time 3 in the IP pseudo header 30
2 and the current time. Then, even if the delivery completion time 32 is reached, if the reconfiguration is not completed, the IP
The data in the middle of the reconstruction is discarded in the same manner as in the reconstruction processing of FIG.

FIG. 9 is a diagram showing a configuration of a time-critical processing unit that performs transmission scheduling based on a delivery time constraint in a transmission control method according to another embodiment of the present invention. In the figure, a time critical communication function execution unit 1, a TC division processing unit 2, a TC reconfiguration processing unit 3
Is the same as that shown in FIG. 1 except that an IP layer 50 is provided in connection with the time-critical communication function execution unit 1 in addition to these components. In the present embodiment, as shown in FIG. 10, a correspondence table of the delivery allowance time is provided corresponding to the Precedence value (priority) of the type of service (Type of Service) value of the IP header, and the delivery allowance time is set. To set the data transmission completion time.

The correspondence table shown in FIG. 10 is provided in the time critical communication function execution section 1 of FIG. And
The data for which the IP layer 50 makes a transmission request to the time-critical communication function execution unit 1 does not have the delivery completion time, but the time-critical communication function execution unit 1
Receives the transmission request data from the IP layer 50, determines whether the data is subject to scheduling,
If it is the target, the schedule is determined by knowing the delivery allowance time indicating how long the transmission must be completed from the current time from the correspondence table. In the correspondence table of FIG. 10, the Prec of the type of service (Type of Service)
If the edence value is 6, the data transmission must be completed within the slot time * 10, and if the edence value is 7, the data transmission must be completed within the slot time * 5. Means. It should be noted that “no correspondence” in the correspondence table means that there is no need to provide a delivery completion time, and is the best delivery data.

[0048]

As described above, according to the first aspect of the present invention, data is divided on the basis of the maximum data length permitted by the data link layer or the scheduling process, and the data is divided into each of the divided data. A time-critical split configuration header including information for reconfiguration and a delivery completion time is added, so that scheduling processing can be performed even on data that is too long, and delivery time is guaranteed even for long data. be able to.

According to the second aspect of the present invention, after scheduling processing is performed on received data, reconfiguration is performed, and the reconfigured data is transmitted to an upper layer.
Scheduling processing can be performed on data that is too long to guarantee delivery time.

According to the third aspect of the present invention, if the reconstruction is not completed even at the delivery completion time, the data in the middle of the reconstruction is discarded. And delivery time can be guaranteed.

According to the fourth aspect of the present invention, the IP header and the delivery completion time are used as an IP pseudo-header, and the data to which the delivery completion time is added is composed of a normal IP header whose protocol is time critical (TC). Since the scheduling process is performed by creating an Internet protocol pseudo-header with the data transmission completion time as the Internet protocol pseudo-header delivery completion time, by using the de facto standard IP header as it is, a normal IP packet is transmitted on the transmission path. Appear to be flowing, and can pass through a relay device such as a router, and scheduling processing can be performed between nodes where the relay device exists.

According to the fifth aspect of the present invention, I
Total length of IP header in P pseudo header (To
tal Length), a flag (Flag), and a fragment offset (Fragment Offset) are used as values when performing division based on the maximum data length allowed by the data link layer or the scheduling process. Since the IP pseudo header is added to the data, the data can pass through a relay device such as a router, and scheduling processing can be performed between nodes where the relay device exists.

Further, according to the present invention, after scheduling the received data, the total length of the IP header in the IP pseudo header is calculated.
th), Flag and Fragment offset
(Fragment Offset) is regarded as a value based on the maximum data length allowed by the data link layer or the scheduling process, and reconfiguration is performed. Therefore, the packet can pass through a relay device such as a router, and the relay device exists. Scheduling between nodes is possible.

According to the present invention, if the reconfiguration is not completed by the time indicated by the completion time of the delivery of the IP pseudo header, the data being reconfigured is discarded. It is possible to pass through the relay device, and scheduling processing can be performed between nodes where the relay device exists.

According to the eighth aspect of the present invention, a correspondence table is provided for defining a spare time for delivery with respect to a Type of Service value of an IP header, and a delivery table is provided to nodes spanning relay devices. When sending data with completion time, type of service (T
ype of Service) and determine the type of service (Type of Service) of the Internet Protocol pseudo-header.
Since this value is set in ce), the packet can pass through a relay device such as a router, and scheduling processing between nodes where the relay device exists can be performed.

According to the ninth aspect of the present invention, I
Type of Service of P header
A correspondence table that defines the delivery allowance time with respect to the
Since the scheduling process is performed on the transmission request data by considering the time obtained by adding the delivery allowance time in the correspondence table to the current time as the delivery completion time of the data, the IP header of the normal IP packet to which the delivery completion time is not added If the Type of Service indicates urgent, by providing a delivery completion time corresponding to this correspondence table, normal IP packets that must be sent earlier can be sent earlier. , Normal TCP or UDP /
It is possible for the IP packet and the data to which the delivery completion time is given to coexist.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a time critical processing unit that performs a time critical process in a transmission control method according to an embodiment of the present invention.

FIG. 2 is a diagram showing a format after a TC division process.

FIG. 3 is a diagram showing a configuration of a data identifier management table.

FIG. 4 is a diagram showing a configuration of a reconfiguration management table.

FIG. 5 is a diagram showing a format of an IP pseudo header.

FIG. 6 is a diagram showing a format of an IP header.

FIG. 7: Type of service of IP header (Type of service)
FIG. 10 is a diagram showing a correspondence table between Service (Service) values and spare time for delivery.

FIG. 8 is a diagram showing a configuration of a division management table.

FIG. 9 is a diagram illustrating a configuration of a time-critical processing unit that performs transmission scheduling based on a delivery time constraint in a transmission control method according to another embodiment of the present invention.

FIG. 10: Type of service (Type) of IP header
It is a figure which shows the correspondence table of the Precedence value of the value of Service) value, and the margin for delivery.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Time critical communication function execution part 2 TC division processing part 3 TC reconstruction processing part 4 TC division reconstruction header 5 Division / reconstruction header 14 Data identifier management table 30 IP pseudo header 33 Division management table 50 IP layer

Claims (9)

[Claims] 1. A data link layer or scheduling process in a communication system for performing transmission scheduling between a plurality of nodes connected to a network and mutually performing data transmission, based on a delivery time constraint between a transmission node and a reception node. When transmitting data exceeding the maximum data length allowed, the transmission data is divided on the basis of the maximum data length allowed by the data link layer or the scheduling process, and each of the divided data is divided and reconfigured. And a time critical (TC) split configuration header having the delivery completion time set in the data received from the upper layer and the data received from the upper layer. 2. After performing a scheduling process on the received data, the data is reconfigured based on information of the time critical division configuration header, and the reconfigured data is transmitted to an upper layer. The transmission control method according to claim 1, wherein 3. The transmission according to claim 2, wherein if data reconfiguration is not completed even after the delivery completion time of the time-critical split configuration header, the data being reconfigured is discarded. control method. 4. A communication system for performing transmission scheduling between a plurality of nodes connected to a network and mutually transmitting data based on a delivery time constraint between a transmission node and a reception node, wherein an Internet Protocol (IP) header is used. The transmission completion time is defined as an Internet protocol pseudo-header, and the data provided with the transmission completion time received from the application is provided with an ordinary Internet protocol header whose protocol is time-critical (TC) and the transmission completion time of the data as the Internet protocol pseudo-header. A transmission control method characterized in that a scheduling process is performed by creating an Internet Protocol pseudo-header with a header delivery completion time. 5. The maximum length of a data link layer or the maximum data length allowed by a scheduling process is determined by setting a total length (Total Length), a flag (Flag) and a fragment offset (Fragment Offset) of an Internet protocol header in an Internet protocol pseudo header. 5. The transmission control method according to claim 4, wherein division is performed as a value when the division is performed as a reference, and an Internet Protocol pseudo header is added to each data after the division. 6. After performing a scheduling process on the received data, a total length (Total Length), a flag (Flag), and a fragment offset (Fragment Offset) of the Internet protocol header in the Internet protocol pseudo header are stored in a data link. 6. The transmission control method according to claim 5, wherein the reconfiguration is performed assuming that the value is based on a maximum data length allowed by a layer or a scheduling process. 7. The transmission control according to claim 6, wherein if the reconfiguration is not completed even at the time indicated by the delivery completion time of the Internet protocol pseudo header, the data being reconfigured is discarded. method. 8. A correspondence table for defining a spare time for delivery with respect to a type of service value of the Internet protocol header, and data with a delivery completion time for a node spanning a relay device. Is transmitted, the type of service (T
ype of Service) and determine the type of service (Type of Service) of the Internet Protocol pseudo-header.
5. The transmission control method according to claim 4, wherein the value is set in ce). 9. A communication system for performing transmission scheduling between a plurality of nodes connected to a network and mutually performing data transmission, based on a delivery time constraint between a transmission node and a reception node, wherein: Type of Servic
e) Set up a correspondence table that defines the delivery allowance time for the value,
A transmission control method, wherein a scheduling process is performed by regarding a time obtained by adding a delivery allowance time in the correspondence table to a current time to Internet protocol transmission request data as a delivery completion time of the data.