JPH02244942A - Transfer confirming system - Google Patents

Abstract

PURPOSE:To make transfer confirmation sure by collectively controlling the transfer confirmation on a multilink, trying resending when a response is not generated within the prescribed time, and when all the signal links are transferred to an interruption mode, trying the reconnection of the single links and resending data. CONSTITUTION:When a response is not generated even when the prescribed time lapses from the transmission of an information transferring frame F1, an error recovery means 4A tries the resending of information to an unconfirmed information transfer frame up to the prescribed number of times. Multilink control means 5A, 5B control the low-order single links 9 for transmitting/receiving the frame and reconnect the single link 9 disconnected during the connecting of the multilink 8. An unconfirmed information transfer frame is resent to a single link connected after disconnecting all the single links 9 and single link control means 6A, 6B inform the connection/disconnection state of the single link 9 to a multilink control means 5A, 5B. Consequently, the generation frequency of faults can be lowered and effective transfer confirmation can be attained.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a delivery confirmation method in a data link control procedure in a multi-link environment where a plurality of links (single links) exist between two adjacent stations. % [Conventional technology] In systems that transmit and receive data, not only in the multilink environment described above, but also in the multilink environment described above, it is necessary to check whether the data transmitted from the local station has definitely reached the other station (delivery confirmation). What you do has important meaning.

By the way, conventional delivery confirmation methods in data link control procedures in a multilink environment only specify information transfer frames with transmission order numbers set as frames to be streamed on the link, and delivery confirmation is not performed as a multilink. , the result of the delivery value L2 obtained by the data link control procedure of each single link constituting the multilink was used as the delivery confirmation. In other words, when a notification of delivery confirmation of an information transfer frame requested to a single link is received from a single link, delivery is confirmed on the multilink, and if confirmation cannot be obtained, the information transfer frame is retransmitted. was.

[Problem to be solved by the invention]

In the conventional delivery confirmation method described above, a feature of a multi-link environment is that as long as at least one single link is connected, data can be sent and received between the local station and the other station, and delivery confirmation can be performed. However, if all single links go into disconnected mode, delivery confirmation is no longer guaranteed, and there is no way to deal with this. That is, conventionally, when all single links have shifted to disconnection mode, it has been treated as a failure occurrence, and no consideration has been given to confirmation of delivery of data transmitted before that.

The present invention has been proposed in view of the above points, and its purpose is to manage delivery confirmation in an integrated manner as a multi-link, and to enable all single links making up the multi-link to switch to disconnection mode. The object of the present invention is to provide a delivery confirmation method that can attempt recovery and ensure delivery confirmation even if the delivery is lost.

[Means to solve the problem]

In order to achieve the above object, the present invention uses a delivery confirmation method in a data link control procedure in a multilink environment, in which a frame dedicated to information transfer containing a transmission sequence number and a reception confirmation number is used as a frame to be sent and received on a multilink, and a In addition to specifying monitoring frames that include fI identification numbers, the order in which frames are transmitted and received is controlled to pass information to lower or higher levels, and the order in which transmission order numbers and reception confirmation numbers are set in frames dedicated to information transfer to be transmitted. control means; response control means for setting a reception confirmation number in a monitoring frame and instructing transmission when there is no information transfer-only frame carrying a response to the received information-transfer-only frame; and sending and receiving during processing by the order control means. a window control means for performing frame window control; an error recovery means for attempting to retransmit an unacknowledged information transfer frame up to a predetermined number of times when there is no response even after a predetermined period of time has elapsed since the transmission of the information transfer frame; In addition to controlling the single link that sends and receives frames, the single link that was disconnected during multilink connection is reconnected, and the single link that was connected after all single links were disconnected is not confirmed. The multilink management means attempts to retransmit a frame dedicated to information transfer, and the single link control means notifies the multilink management means of the connection/disconnection status of a single link.

[Effect]

In the delivery 61 recognition system of the present invention, the order control means controls the order of frames to be sent and received, passes information to a lower or higher order, and sets a transmission order number and a reception confirmation number in a frame dedicated to information transfer to be sent. However, if there is no information transfer dedicated frame to carry a response to the received information transfer dedicated frame, the response control means sets a reception confirmation number in the monitoring frame and instructs transmission, and the response control means sets a reception confirmation number in the monitoring frame and instructs transmission, and when processing the order control means, the response control means The window control means performs window control, and if there is no response even after a predetermined period of time has elapsed since the transmission of the information transfer frame, the error recovery means attempts to retransmit the unacknowledged information transfer frame up to a predetermined number of times, and the multilink The management means controls the lower single link that transmits and receives frames, and also handles the single link that is disconnected during multilink connection.
The single link controller attempts to retransmit unconfirmed information transfer dedicated frames to the connected single links after all single links are disconnected, and the single link control means determines the connection/disconnection status of the single links. to the multilink management means.

〔Example〕

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

FIG. 1 is a block diagram showing an embodiment of the delivery confirmation system of the present invention. In FIG. 1, this embodiment is comprised of a local station A, a partner station B, and a multilink 8 that connects the two stations. Note that the multi-link 8 is a plurality of single links 9.
It consists of

In addition, Fl and F2 are frames transmitted and received on the multilink 8, and Fl is a frame dedicated to information transfer that includes an information transfer dedicated frame identifier a, a transmission sequence number, a reception confirmation number C, and information d, as shown in FIG. , F2 is a monitoring frame including a monitoring frame identifier e and a reception confirmation number f, as shown in FIG.

On the other hand, the own station A and the other station B have the same configuration regarding the delivery confirmation function, and include an order control means IAIB, response control means 2A, 2B, window control means 3A, 3B, error recovery means 4A, 4B, and multi-link management means 5A.

5B, single link control means 6A, 6B, and response waiting timers 7A, 7B. The functions of each part are explained according to the flowcharts in Figures 4 to 9.
Explain through actions.

The operation of the above embodiment will be explained below. Note that the local station A will be explained.

FIG. 4 is a flowchart showing the processing of the order control means IA in FIG. In FIG. 4, in the case of transmission, the order control means IA instructs "send" and calls the window control means 3A (step 101), and determines whether transmission is possible based on the response returned from the window control means 3A (step 101). Step 102), if transmission is possible (Step 10)
2), the transmission 1 sequence number and reception confirmation number passed from the window control n means 3A are sent to the slots and c in the information transfer frame Fl, and the response waiting timer 7 is sent.
A is started (step 103), the multilink management means 5A is requested to transmit the frame F1 exclusively for information transfer (step 104), and the process is ended. If transmission is not possible (No in step 102), the information transfer dedicated frame Fl is registered at the end of the transmission waiting queue (step 105), and the process ends.

On the other hand, in the case of reception, "receive" is instructed and the window control means 311 is called 3A (step 106), and it is determined whether the received frame is an information transfer-only frame Fl or a monitoring frame F2 (step 107). ), if the received frame is an information transfer-only frame F1 (YES in step 107), it is further determined whether reception is OK or reception is pending (step 108), and if reception is OK, the response transmission requirement is temporarily memorized in step 109. ), hands over the received information transfer dedicated frame F1 to the upper layer (step 110), and in the case of pending reception (N of step 108).
o), the received information transfer-only frame Fl is temporarily put on hold (step 111), and -, when the received frame is the monitoring frame F2 (step 107
) and step 7b11 after step 11.0.111
Proceed to step 2, and check whether the information transfer dedicated frame F1 to be transmitted is registered in the transmission waiting queue (step 1).
12), if registered (YES in step 112)
), proceed to step 101; if not registered (
If the response transmission requirement is stored (step 113), if it is stored (step 113: YES), a request is made to the two response control means to transmit a response (step 114). ), if it is not stored (NO in step 113), the process ends without doing anything.

FIG. 5 is a flowchart showing the processing by the two response control means in FIG. In FIG. 5, when the response control means 2A is activated and starts processing, it acquires the current reception confirmation number from the window control means 3A (step 20).
1) The obtained reception confirmation number is sent to f in the monitoring frame F2.
202), adds 1 to the reception confirmation number (Step 203), makes a transmission request to the multilink management means 5A (Step 204), and ends the process.

FIG. 6 is a flowchart showing the processing of the window control means 3A in FIG. In FIG. 6, when the window control means 3A is activated and starts processing, it determines the received instruction (step 301), and in the case of a transmission instruction (transmission in step 301), the current transmission order number and delivery Compare the number with the confirmed number (Step 302), and determine whether the difference is within the transmission window size (Step 3).
03), if it is within the transmission window size (step 30
If YES in step 3), add 1 to the transmission order number to indicate ``send possible'' (Step 304), and if it exceeds the transmission window size, indicate ``send not possible'' (step 305).
, each process ends.

On the other hand, in the case of a reception instruction (reception in step 301), it is determined whether the received frame is the information transfer-only frame F1 or the monitoring frame F2 (step 306), and if it is the information transfer-only frame F (step 306: YES). compares the transmission order number in the frame with the reception confirmation number managed by the station itself (step 307), and determines whether the difference is greater than the reception window size or double reception (step 308); If so (step 3
08), the received frame is to be discarded (step 312), but the reception confirmation number included in the received frame is not discarded.

In addition, in the case of a normal information transfer dedicated frame F1 (No in step 308), it is checked whether the two numbers mentioned above are equal (step 309), and if they are equal (step 309
YES), instruct “OK to receive” in step 310.
), if they are not equal (step 309ON), instruct "reception hold" as advance reception (step 311)
.

The frame received in step 306 is the monitoring frame F2.
If so, and after steps 312, 310, and 31.1, the process proceeds to step 313, and the reception confirmation number C in the received information transfer dedicated frame Fl or the monitoring frame F2 is
If f is obtained (step 313), the received if
Check the transmission order number for which delivery confirmation has not been obtained from the own station using the L'2 number, and update it as necessary in step 314.
), all delivery 6m. If acknowledged, the response wait timer is stopped (step 315), and the process ends.

FIG. 7 is a flowchart showing the processing of the error recovery means 4A in FIG. In FIG. 7, the error recovery means 4A is activated and starts processing when the response waiting timer 7A times out. The process is to add 1 to the number of retransmissions (Step 401), then compare it with the specified number of times (Step 402), and if it exceeds the specified number of times (No in Step 402), it is determined that the other station is at fault (Step 404).
, ends the process. If the number of times is within the specified number (YES in step 402), the order control means IA is requested to correct the transmission window and retransmit (step 40).
3).

FIG. 8 is a flowchart showing the processing of the multilink management means 5A in FIG. In FIG. 8, in the case of transmission, the multi-link management means 5A searches for a transmittable single link 9 (step 501), determines whether it is found (step 502), and if found (
If YES in step 502), transmission is requested to that single link (step 503), and the process ends.

Also, if it is not found (No in step 502)
However, it is determined that the transmission is OK (step 504).

In other words, since there is no way to deal with the transmission failure, the transmission is determined to be OK, and if there is no response from the other party, the response is to retransmit the transmission.

In the case of reception, the received frames are sent to the order control means IA.
At step 505), the process ends.

In the case of a single link disconnection notification, it is determined whether the multilink 8 is connected (step 506), and if it is connected (YES in step 506), the single link is instructed to start a reconnection procedure. Step 507)
, ends the process. If it is not connected, ignore it and end the process.

In the case of a single link connection notification, it is determined whether all other single links are disconnected (step 50B), and if they are disconnected (YES in step 508), the transmission window is modified and the information is sent to the order control means IA. Transfer-only frame F
A request is made to send (retransmit) 1 (step 509), and the process ends. If there is another single link being connected (No in step 508), the process ends without doing anything in particular.

FIG. 9 is a flowchart showing the processing of the single link control means 6A in FIG. In FIG. 9, the single link control means 6A is connected when the connection is completed!
A notification is given to the multilink management means 5A (step 60
1) If the disconnection is complete, a disconnection notification is given to the multilink management means 5A (step 602), and the respective processes are ended.

〔Effect of the invention〕

As explained above, in the delivery confirmation method of the present invention,
Manages delivery confirmations on multiple links in an integrated manner, and in addition to attempting retransmission if there is no response within a predetermined time, attempts to reconnect single links if all single links have gone into disconnected mode. Since the system retransmits the data, if even one single link can be connected within the allowable time, the multi-link will not be disconnected, resulting in a significant reduction in the frequency of failures and effective delivery confirmation.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the delivery 6i Ul method of the present invention, Fig. 2 is a logical block diagram of an information transfer dedicated frame, Fig. 3 is a logical block diagram of a monitoring frame, and Fig. 4 is a block diagram showing an embodiment of the delivery 6i Ul method of the present invention. 5 is a flowchart of the processing of the response control means, FIG. 6 is a flowchart of the processing of the window control means, FIG. 7 is a flowchart of the processing of the error recovery means, and FIG. 8 is a flowchart of the processing of the error recovery means. FIG. 9 is a flowchart of the processing of the management means, and FIG. 9 is a flowchart of the processing of the single link If 11 means. In the diagram, A・・・・・・・・・・・・My station B・・・・・・
......Other station LA, IB...order fil
Control means 2A, 2B...Response control means 3A, 3B...Window control means 4A, 4B...Error recovery means 5A, 5B...Multilink management means 6A, 6B...
・Single link control means 7A, 7B...response wait timer

Claims (1)

[Claims] In a delivery confirmation method in a data link control procedure in a multilink environment, frames sent and received on a multilink include an information transfer dedicated frame including a transmission order number and a reception confirmation number, and a reception confirmation number. a monitoring frame, controlling the order of transmitted and received frames to pass information to a lower or higher level, and setting a transmission order number and a reception confirmation number in a frame dedicated to information transfer to be transmitted; response control means for setting a reception confirmation number in a monitoring frame and instructing transmission when there is no information transfer dedicated frame carrying a response to the information transfer dedicated frame; and performing window control of frames to be sent and received during processing by the order control means. a window control means; an error recovery means for attempting to retransmit an unacknowledged information transfer frame up to a predetermined number of times when there is no response even after a predetermined period of time has elapsed since the transmission of the information transfer frame; In addition to controlling links, it reconnects single links that were disconnected during multilink connection, and retransmits unconfirmed information transfer frames for single links that are connected after all single links are disconnected. 1. A delivery confirmation method comprising: a multi-link management means for making a connection/disconnection of a single link; and a single-link control means for notifying the multi-link management means of the connection/disconnection status of a single link.