KR970009708B1 - Method for transmitting and receiving data between a processor and other process in an exchanger - Google Patents

Abstract

The method of transmitting/receiving interprocessor data of an exchange system comprises the steps of: requesting a communication by a transmitting party and a receiving party and allowing the communication request; and transmitting/receiving data; and controlling an error according to a data frame or a confirmation frame.

Description

How to send and receive data between processors in exchange

The present invention relates to an exchange, and more particularly, to a method for transmitting and receiving data between processors of an exchange suitable for allowing each processor of the electronic switch to transmit and receive data at high speed.

In general, in TDX-IA / IB, in the processor-to-processor communication, reliability communication, that is, when data is transmitted from one processor to another processor to confirm receipt, that is, data is transmitted from DKIP to MTIP or MTK to DKIP. In the case of transmitting data through the network, the processor communicates by the handshake method in units of interprocessor communication (IPC) frames.

As described above, in transferring large amounts of data from one processor to another in interprocessor communication of a conventional exchange, it has been a problem to transmit large amounts of data in high speed and reliable communication.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem. In the inter-processor communication of an exchange, when a large amount of data is transmitted from one processor to another processor, the processor-to-processor data of the exchange enabling reliable communication at high speed can be transmitted and received. The purpose is to provide a way to.

In order to achieve the above object, the present invention provides a communication request and permission step for requesting and allowing communication between a sender and a receiver, and a data transmission / reception step for transmitting and receiving data; An error control step of controlling an error caused by the loss of a data frame or an acknowledgment frame, the requesting and allowing step comprising: a first step of requesting and allowing communication from a program on a processor, such as a sender, to the data sender; A second step in which the receiver requests and permits communication to the data sender, a third step in which the data receiver requests and permits communication in a program on the same processor as the receiver, and a second step in which the sender requests and permits the data to the data receiver. It is characterized by consisting of four steps.

1 is a diagram showing the structure of the type of communication message and the type of the communication message used between each processor according to the method of transmitting and receiving data between processors of the exchange of the present invention.

2 is a flowchart illustrating a transmission process algorithm according to a method of transmitting and receiving data between processors in an exchange of the present invention.

3 is a flowchart illustrating a receiving process algorithm according to a method of transmitting and receiving data between processors in an exchange of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The electronic switching system to which the present invention is applied consists of a plurality of processors, each of which is connected by a network, and has a function of communicating with a desired processor as a processor identifier.

Hereinafter, in the meaning of the terms used in the present invention, TS and TR are timers, TS is a sender timer, and TR is a receiver timer.

First, in case of an algorithm of the transmitting processor, the timer TS00 denotes a time to wait for a response after the sender's communication request, the timer TS01 denotes a time to wait for a response after transmitting data, and the timer TS02 retransmits the data. It means the time to wait until the response, and the map managed by the sender occupies one field per frame, and the field has three states, namely, state NT means that the data has not been transmitted yet. In this case, state NA means that the data is transmitted but not allowed to communicate, and state AK means that the data is transmitted and allowed to communicate.

Next, in the algorithm of the receiving processor, the timer TR00 means waiting time until a response after communication request from the destination, and the timer TRO1 means waiting time when the number of frame receptions is smaller than the number of windows, and the timer TRO3 is The waiting time when the receiver confirms receipt of the frame and does not allow the other party to communicate. The map managed by the receiver occupies one field for each frame, and the field has four states. State NK means the state that has not been received yet, state NK means the state that has received data and has not confirmed the communication permission, state NH means the state that allows communication and has not confirmed the communication permission, state AD means communication Means the condition that the sender has received the permission.

Referring to FIG. 1, there is shown a diagram showing the types of contact messages and the structure of the types of contact messages used between processors according to a method of transmitting and receiving data between processors of an exchange of the present invention. ) Is a communication request frame COM_REQ, and FIG. 1 (c) (d) is a communication permission frame COM_ACK, and FIG. 1 (e) (f) is a data transmission frame DATA_FKM and a data receiving frame DATA_ACK, and FIG. ) Shows the structure of the transmission end message DATA_END, respectively.

First, (a) of FIG. 1 is a case where a sender starts, COM_REQ means a message type, a receiving process ID means a receiving address, a sending process ID means an originating address, and MAX_FRM_NM means a frame number, respectively. do.

FIG. 1 (b) shows a case where the receiver starts, COM_REQ means a message type, a sending process ID means a receiving address, a receiving process ID means a source address, and MAX_WIN_SZ means a window size. .

Next, as illustrated in FIG. 1C, when the sender starts, COM_ACK means a message type, a transmitting process ID means a receiving address, a receiving process ID means a source address, and MAX_WIN_SZ means a frame size, respectively. .

FIG. 1 (d) shows a case in which the receiver starts, COM_ACK means a message type, a receiving process ID means a receiving address, a transmitting process ID means a source address, and MAX_FRM_NM means a frame number, respectively. .

Next, DATA_FRM in FIG. 1 (e) means a message type, a receiving process ID means a receiving address, a sending process ID means an originating address, and a data frame sequence number means a sequence number, respectively. Is the last data in byte unit.

Next, DATA_ACK in FIG. 1 (f) means a message type, a transmission process ID means a reception address, a reception process ID means a source address, and the number of ACK frames means a frame number and a frame sequence number. Denotes an ACK frame sequence number array, respectively, from the first frame sequence number to the last frame sequence number.

In addition, DATA_END in FIG. 1 (g) denotes a message type, and a transmission process ID denotes a reception address, respectively.

Hereinafter, the terms described above are regarded as having been given meaning according to the description of the terms, and the terms are used.

2 is a flowchart illustrating a transmission process algorithm according to a method of transmitting and receiving data between processors of an exchange in the present invention, in which a communication is initiated by a nova (14) and a case is initiated by a receiver (11). The process is the same.

First, in the communication 14 initiated by the sender, the sender transmits a COM_REQ message of a communication request frame including information on the number of frames to be transmitted to the receiver (15, 16), and receives a communication permission frame of the COM_ACK from the receiver (17 to 16). 19) After extracting information about the size of the window included in the frame enters the data transmission mode.

Next, when a COM_REQ message of a communication request frame including information on a window size from a receiver arrives at the sender (11), the receiver requests data transmission to the receiver, and sends a COM_ACK including the total frame number information to the receiver (recipient). 12, 13) and enter the data transfer mode.

Thereafter, the map information indicating whether the ACK for all frames is initialized to NT state (20), the window is changed, and transmission is started with DATA_FRM.

Subsequently, transmission is continued until the number of frames in the NA state reaches the maximum window size while changing the NT state, which has not been transmitted, to the NA state (21 to 24).

If the number of messages in the NA state is equal to the maximum size of the window (21), or if there are no more frames in the NT state (23), the timer TS01 is activated (25) and waits for a DATA_ACK frame (26). When the timer TS01 is temporarily stopped (Timeout) at 28, retransmits 36 frames in the NA state and starts the timer TS02 (37).

Subsequently, when timer TS02 is interrupted for a while (27), it is considered that transmission is impossible and communication is interrupted (38).

When the DATA_ACK frame arrives (29), all timers are stopped (30) and the map field corresponding to the ACK frame sequence number stored in the frame is changed to the acknowledgment AK state (31).

In addition, if all frames are ACKed (32), it transmits DATA_END frame (35) and notifies the end of communication. (33).

Next, the timer TS01 is started (34) and returned to the waiting state (26).

3 is a flowchart illustrating a receiving process algorithm according to a method of transmitting and receiving data between processors of an exchange of the present invention. First, when a receiver starts communication (44), a communication request message including a window size is sent to the sender (45). The timer TROO starts to wait for communication (46).

At this time, if the interruption (48) for a while, it is reported that communication with the sender is impossible (63).

Next, when the communication permission message comes (47), the state of the entire frame is initialized to the NR state and enters the data reception mode (49).

Subsequently, when a data transmission request is received from the sender (41), a communication permission message (42,43) including the window size information is transmitted (42, 43), and the state table of the frame is initialized (49) to enter the data reception mode (69).

In the data reception mode, the timer TROO is started (69). If the timer TROO is stopped (50, 54), communication is considered impossible (63).

Then, when the receiver receives DATA_FRM (51), it keeps all timers (55) and if it is DATA_END that the frame has transmitted all data (56) the communication is over, otherwise it is received at the corresponding position as the sequence number stored in the received frame. Save the frame (57).

Subsequently, when the corresponding map field is in the NR state, the state changes to the NK state, and the counterparts that are NH change to the AD state (57).

When the number of frame NK states that have not yet sent DATA_ACK is equal to the maximum size of the window, the NK state field is changed to NH state (61), and the DATA_ACK for acknowledging the frame of the window size is transmitted (59).

At this time, the timer TRO2 is activated (60) and returns to the standby state (50).

On the contrary, if the number of frame NK states for which DATA_ACK has not been sent yet is not equal to the window size, the timer TS01 is activated (62) and the process returns to the standby state (50).

In addition, if the timer TRO2 is stopped (53) while transmitting DATA_ACK, it is recognized that the DATA_ACK frame is lost, retransmits the ACK for the NH state frames (66), and operates the timer TRO3 (67).

Next, when the timer TRO1 is stopped 52 in the waiting state, it is determined that some of the frames transmitted by the sender are lost, and an ACK is transmitted to the frames whose state is NK state, and the state of the frames is changed to the NH state. (64,65).

When the timer TRO3 is stopped 54 in the waiting state, it is determined that communication is impossible and the communication is stopped (63).

As described above, the present invention provides a modified sliding window protocol and selective retransmission on a connectionless channel when transferring a large amount of data from one processor to another in interprocessor communication of an exchange. By modifying and combining the Selective Retransmission method and reducing the load of the physical link by using the multiple communication permitting method, a large amount of data can be reliably transmitted between processors at high speed.

Claims (3)

In the interprocessor communication of an electronic switchgear, a communication requesting and permitting step in which a sender and a receiver request and permit communication; A data transmission and reception step of transmitting and receiving data; And an error control step of controlling an error caused by the loss of a data frame or an acknowledgment frame, wherein the requesting and permitting step includes a first step of requesting and allowing communication from a program on a processor such as a sender to the data sender ( 11 to 13), a second step (14 to 19) in which the receiver requests and permits the communication of the data sender (14 to 19), and a third step (44 to a request, which permits the communication of the data receiver in a program on a processor such as the receiver). 48) and a fourth step (41 to 43) in which the sender requests and permits communication to the data receiver. The method of claim 1, wherein the data transmitting / receiving step includes a sender initializing a state of a map for a whole frame, transmitting a frame corresponding to a window size, changing a state of a map, waiting for a reception response, and transmitting a frame upon reception. The first step (20 to 35) of changing to the acknowledgment state and sending another frame of window size if there are more frames to be sent, and if the receiver receives the frame from the sender and receives the frame size from the sender, A second step (49 to 62) for transmitting an acknowledgment frame for and changing the state of the map for the acknowledgment frame and changing the acknowledgment frame allowance state for the frame in which the acknowledgment frame was transmitted before each frame reception. A method for transmitting and receiving data between processors of an exchange comprising a. 2. The method of claim 1, wherein the error control step comprises a first step (36,37) of retransmitting unanswered frames when the receiver does not respond in time and when the sender does not transmit the next data frame in time. A second step (64, 65) of transmitting an acknowledgment frame for frames not sending a response and changing the current state to the response transmission state; and if the message does not arrive within a certain time after the response is sent. And a third step (66,67) of remajorizing an acknowledgment frame for transmission status frames.