KR100628746B1 - Duplexing method of signalling atm adaptation layer - Google Patents

Abstract

A duplexing method of signaling ATM adaptation layer(SAAL) is provided to perform the switching promptly without initiating SAAL for switching or without transmitting duplexing information when the function is disabled. In duplexing method of signaling ATM adaptation layer(SAAL), the SAAL is composed of active SAAL and standby SAAL. The respective SAAL receives the message from the upper level or lower level(S401). The respective SAAL processes the received message and stores the duplexing data(S402). The respective SAAL transmits a sequence number(SN) through a duplexing window to the standby SAAL(S403). The standby SAAL detects whether the corresponding data exists in the received SN or not(S404). The standby SAAL requests the transmission of corresponding data again if the corresponding data does not exist in the received SN(S405). The active SAAL detects the corresponding data(S406) and transmits the data to the standby SAAL(S407).

Description

Duplexing method of SARA {Duplexing method of Signaling ATM Adaptation Layer}

1 is a block diagram showing a redundant configuration of a typical SAAL.

FIG. 2 is a block diagram showing the configuration of the redundancy processor of FIG. 1. FIG.

3 is a flowchart illustrating a duplication method of SAAL according to an embodiment of the present invention.

4 is a flowchart illustrating a method of processing redundant data of a SAAL according to an embodiment of the present invention.

5 is a flow chart showing a conventional method of duplication of SAAL.

Explanation of symbols on the main parts of the drawings

10: SAAL 20: SAAL User Layer

30: ATM Layer 100: Active SAAL

110: SAAL user layer interface 120: SAAL processing unit

130: ATM layer interface 140: SAAL state management unit

150: redundant processing unit 160: storage unit

200: standby SAAL

The present invention relates to a method of redundancy of a signaling ATM adaptation layer (SAAL), and more particularly, reduces the load for redundancy by sharing only a sequence number (SN) in a SAAL composed of active and standby. The present invention relates to a method of duplication of a SAAL that can be quickly changed without a separate treatment for switching in the event of a failure.

In general, Asynchronous Transfer Mode (ATM) is a method of dividing all information into fixed-length blocks called ATM cells and transmitting them sequentially. Dedicated-connection switching technology that transmits through a medium using technology.

The ATM layer is divided into four types: a physical layer, an ATM layer, an ATM adaptation layer (AAL), and a user layer. In particular, the AAL layer expresses a data structure of an upper application layer as a cell structure of an ATM layer. Provides functions, operation and management functions.

On the other hand, specific channels are used to convey signaling information in ATM, similar to the D channel of narrowband ISDN. The AAL layer of these signaling channels is called Signaling Adaptation Layer (SAAL) and is defined in Q.2100 of ITU-T. have.

This SAAL is responsible for converting the signaling protocol of the application layer (eg Q.2931, B-ISUP) to the signaling protocol used at the ATM level.

In addition, SAAL is a protocol in which the order should be corrected, and a duplication method is used for stable processing in a system using the SAAL, and the duplication configuration of the SAAL is shown in FIG.

1 is a block diagram showing a redundant configuration of a typical SAAL.

The SAAL 10 includes an active SAAL 100 for transmitting and receiving messages from the SAAL user layer 20 and the ATM layer 30, and a standby SAAL 200 for switching in case of a functional failure.

The active SAAL 100 transmits and receives a message with the SAAL user layer interface 110 that transmits and receives a message to and from the SAAL user layer 20, the SAAL processor 120 that processes the received message, and the ATM layer 30. An ATM layer interface 130, a SAAL state management unit 140 for managing the SAAL state changed by the SAAL processing unit 120, a duplication processing unit 150 for transmitting and receiving redundancy related messages with the standby SAAL 200, and various It is composed of a storage unit 160 for storing data.

The standby SAAL 200 includes a SAAL user layer interface 210 for transmitting and receiving a message to and from the SAAL user layer 20 when switching, a SAAL processing unit 220 for processing a received message when switching, and an ATM layer 30 for switching. Transmitting / receiving a duplication related message between the ATM layer interface 230 for transmitting and receiving a message, the SAAL state management unit 240 for managing the SAAL state changed by the SAAL processing unit 220, and the active SAAL 100. The redundancy processing section 250 and a storage section 260 for storing various data.

The SAAL 10 configured as described above processes messages received from the SAAL user layer 20 and the ATM layer 30 by the active SAAL 100 during normal operation, and the active SAAL 100 is transferred to the standby SAAL 200. Send only SAAL status.

On the other hand, when a functional failure of the active SAAL (100) or the corresponding module is mounted, the SAAL (10) transfers the function of the active SAAL (100) to the standby SAAL (200), the standby SAAL (200) for such switching ) Is initialized or all the redundancy information stored in the active SAAL (100) is transmitted.

5 is a flowchart illustrating a conventional method of duplication of SAAL.

First, in step S501, the SAAL 10 operates by the active SAAL 100 to receive a message from the SAAL user layer 20 through the SAAL user layer interface 110, or through the ATM layer interface 130, ATM layer. Upon receiving the message from 30, the duplication method of SAAL 10 is initiated.

In this case, the SAAL processing unit 120 of the active SAAL 100 processes the received message, the SAAL state management unit 140 manages the SAAL state, such as connection information according to the message processing, the state information is stored Stored at 160.

In operation S502, the duplication processing unit 150 of the active SAAL 100 transmits SAAL state information to the duplication processing unit 250 of the standby SAAL 200 through the duplication channel.

In operation S503, the duplication processing unit 250 of the standby SAAL 200 stores the received SAAL state information in the storage unit 260, thereby synchronizing with the SAAL state of the active SAAL 100 for redundancy.

If it is determined in step S504 that the functional failure of the active SAAL 100 has occurred and the transfer should be performed, the process proceeds to step S505 to prepare for switching and if the functional failure of the active SAAL 100 does not occur, that is, the transfer is performed. If not necessary, the process returns to step S501 to continuously perform the message processing and the duplication processing of steps S501 to S503.

In step S505, the standby SAAL 200 is initialized to perform message processing between the SAAL user layer 20 and the ATM layer 30, or by requesting the duplication information from the active SAAL 100 to receive the duplication information. Then prepare for the transfer.

In step S506, the SAAL 10 transfers the active SAAL 100 to the standby SAAL 200 to perform its function.

In this manner, the SAAL 10 may perform a normal SAAL function by switching to the standby SAAL 200 even when a malfunction of the active SAAL 100 that is normally operated occurs.

However, in the conventional SAAL duplication method, since the active SAAL transmits only the SAAL state to the standby SAAL through the duplication channel, the standby SAAL must be initialized or all the SAAL duplication information must be received from the active SAAL for switching when a functional failure occurs. . Therefore, there is a problem in that the switching is delayed according to the operation for switching and the overload of the redundant channel due to the duplication occurs.

The present invention has been proposed to solve the above problems, the active SAAL on the SAAL to be ordered guarantees to share only the SN to the standby SAAL to reduce the load for redundancy, and in the event of a functional failure quickly without additional processing It is an object of the present invention to provide a method for redundancy of a SAAL that can be switched.

According to an aspect of the present invention, there is provided a method of duplexing a SAAL including an active SAAL and a standby SAAL, the method comprising: receiving a message from each SAAL from a higher or lower layer; A data storage step of each SAAL processing the received message to store redundant data; An SN transmission step in which the active SAAL transmits an SN to the standby SAAL through a redundant window; A retransmission request step of searching for whether there is data corresponding to the received SN by the standby SAAL and requesting retransmission of the corresponding data to the active SAAL when there is no corresponding data; And a data transmission step of searching for the corresponding data by the active SAAL and transmitting the data to the standby SAAL.

Preferably, the redundant data includes an SN, a data pointer, and SAAL connection information.

According to another aspect of the present invention, there is provided a SAAL duplication method, comprising: a SAAL duplication method comprising an active SAAL and a standby SAAL, each SAAL receiving a message from an upper layer or a lower layer; A message processing step in which each SAAL processes the received message; A duplication step wherein each SAAL maintains the same duplication data through a duplication window; A transfer determination step of determining whether or not the active SAAL is to be transferred; And when the active SAAL is switched, the standby SAAL replaces the function of the active SAAL.

Advantageously, said redundancy step comprises: an SN transmission step in which said active SAAL transmits an SN to said standby SAAL through a redundancy window; A retransmission request step of searching for whether there is data corresponding to the received SN by the standby SAAL and requesting retransmission of the corresponding data to the active SAAL when there is no corresponding data; The active SAAL retrieves the data and transmits the data to the standby SAAL.

The above objects, features, and advantages will become more apparent from the following description of the embodiments with reference to the accompanying drawings.

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

FIG. 1 is a block diagram illustrating a general SAAL duplication configuration for explaining a duplication method of a SAAL according to an embodiment of the present invention, and FIG. 2 is a block diagram illustrating a configuration of a duplication processing unit of FIG. 1.

The SAAL 10 receives active messages from the SAAL user layer 20 and the ATM layer 30, and receives and processes the messages from the SAAL user layer 20 and the ATM layer 30. It is configured as a standby SAAL (200) for switching when a function failure occurs by storing the.

The active SAAL 100 transmits and receives a message to and from the SAAL user layer interface 110, which transmits and receives a message to and from the SAAL user layer 20, the SAAL processor 120, which processes the received message, and the ATM layer 30. A duplication processing unit 150 for transmitting and receiving duplication related messages between the ATM layer interface 130, the SAAL state management unit 140 managing the SAAL state changed by the SAAL processing unit 120, and the standby SAAL 200; The storage unit 160 stores various data.

The duplication processing unit 150 stores a user message processed by the SAAL processing unit 120, that is, a redundancy window 152 storing a SN, a data pointer, and connection information according to an SD Sequenced Data Protocol Data Unit (PDU) and a standby SAAL ( It consists of a redundant message processing unit 154 for transmitting and receiving a message with the duplication processing unit 250 of the 200.

The standby SAAL 200 is a SAAL user layer interface 210 for transmitting and receiving a message with the SAAL user layer 20, a SAAL processing unit 220 for processing the received message, ATM layer 30 and receives the message An ATM layer interface 230, a SAAL state management unit 240 for managing the SAAL state changed by the SAAL processing unit 220, a duplication processing unit 250 for transmitting and receiving redundancy related messages with the active SAAL 100, and various The storage unit 260 stores data.

The SAAL 10 configured as described above may process messages received from the SAAL user layer 20 and the ATM layer 30 by the active SAAL 100 and the standby SAAL 200, respectively. The received user message, that is, the SN, the data pointer, and the connection information associated with the SD PDU are stored in the duplication window 152 and the SN is transmitted to the standby SAAL 200.

The standby SAAL 200 determines the presence or absence of the corresponding data according to the received SN, and if there is no corresponding data, requests that the active SAAL 100 retransmit the corresponding data, the active SAAL 100 stores the corresponding data. Search) and transmit to standby SAAL 200.

The standby SAAL 200 stores the corresponding data received from the active SAAL 100 in the storage unit 260, thereby maintaining a duplication state for switching.

Therefore, when a function failure of the active SAAL 100 occurs or the corresponding module is dismounted, the SAAL 10 transfers the active SAAL 100 to the standby SAAL 200 without performing a separate preparation process and performs its function.

Hereinafter, a duplication method of SAAL according to an embodiment of the present invention will be described with reference to FIGS. 3 to 4.

3 is a flowchart illustrating a duplication method of SAAL according to an embodiment of the present invention.

First, in step S301, the SAAL 10 is operated by the active SAAL 100 to receive a message from the SAAL user layer 20 through the SAAL user layer interface 110, or through the ATM layer interface 130, ATM layer Upon receiving the message from 30, the duplication method of SAAL 10 is initiated.

At this time, user messages among the received messages are received in the form of SD PDUs, and the order of these SD PDUs should be guaranteed.

Meanwhile, the standby SAAL 200 receives a message from the SAAL user layer 20 and the ATM layer 30 similarly to the active SAAL 100.

In step S302, the SAAL processing unit 120 of the active SAAL 100 processes the received message, and the SAAL processing unit 220 of the standby SAAL 200 also processes the received message.

In operation S303, the duplication processing unit 150 of the active SAAL 100 stores the SN, data pointer, and connection information related to the received SD PDU in the duplication window 152, and transmits the SN to the standby SAAL 200. The standby SAAL 200 searches for data corresponding to the received PN.

At this time, when the standby SAAL 200 determines that there is no corresponding data, the standby SAAL 200 requests the active SAAL 100 to retransmit the corresponding data, receives the corresponding data, and stores the received data in the storage unit 260 to perform the redundancy process. .

In step S304, the presence or absence of functional failure of the active SAAL 100 is monitored, and it is determined whether to switch over according to the result, and when it is determined that the transfer is not performed, that is, when there is no functional failure of the active SAAL 100, the process goes to step S301. The message processing and redundancy processing in steps S301 to S302 are continuously performed.

If it is determined in step S304 that the SAAL 10 is switched, that is, if a malfunction of the active SAAL 100 occurs, the process proceeds to step S305 and the SAAL 10 performs the active SAAL 100 without any additional processing. Is transferred to the standby SAAL (200) to perform its function.

In this manner, the duplication method of the SAAL 10 is terminated.

4 is a flowchart illustrating a method of processing redundant data of a SAAL according to an embodiment of the present invention.

First, in step S401, the SAAL 10 operates by the active SAAL 100 to receive a message from the SAAL user layer 20 through the SAAL user layer interface 110, or through the ATM layer interface 130, ATM layer. Upon receiving the message from 30, the method of processing the redundant data of the SAAL 10 is disclosed.

At this time, the standby SAAL 200 receives a message from the SAAL user layer 20 and the ATM layer 30 like the active SAAL 100.

In operation S402, the SAAL processing unit 120 of the active SAAL 100 processes the received message, and the SAAL processing unit 220 of the standby SAAL 200 also processes the received message.

At this time, each of the active SAAL 100 and the standby SAAL 200 stores the SN, data pointer, and connection information associated with the received SD PDU in each duplication window 152.

In step S403, the active SAAL 100 transmits the SN stored in the duplication window 152 indicated by the duplication window pointer according to the processed message to the standby SAAL 200.

In step S404, the standby SAAL 200 searches for data corresponding to the received PN in a redundant window to determine whether there is corresponding data, and if there is data, does not perform separate redundant data processing. Proceed to S408.

If the standby SAAL 200 determines that there is no data corresponding to the received PN, the process proceeds to step S405 and requests the transmission of the data to the active SAAL 100 through the redundancy processor 250.

In operation S406, the active SAAL 100 searches for data stored in the storage 160 by referring to the data pointer stored in the duplication window 152.

In operation S407, when the active SAAL 100 searches for data in the form of an SD PDU and transmits the data to the standby SAAL 200 through the duplication processing unit 150, the standby SAAL 200 stores the received data in the storage unit 260. ), The redundancy process is performed.

In step S408, it is determined whether to end the series of message processing, and if it is determined that the message processing is not to be terminated, that is, when the message is continuously received, the process returns to step S401 to perform the message processing and the redundant data processing of steps S401 to S407. Perform continuously

If it is determined in step S408 that the message processing is terminated, the duplication data processing method of SAAL 10 in steps S401 to S407 ends.

As described above, in the SAAL duplication method according to the present invention, the active SAAL does not transmit all the SAAL message data to the standby SAAL, instead of the standby SAAL, on the SAAL whose order is to be guaranteed. In addition to reducing the load for redundancy by minimizing the number, there is an effect that the switchover can be performed quickly without the need to initialize the SAAL or transmit redundancy information for switching in case of a functional failure.

Claims (4)

In the SAAL duplication method consisting of an Active Signaling ATM Adaptation Layer (SAAL) and a Standby SAAL, A message receiving step in which each SAAL receives a message from an upper or lower layer; A data storage step of each SAAL processing the received message to store redundant data; An SN transmission step in which the active SAAL transmits a sequence number (SN) to the standby SAAL through a redundancy window; A retransmission request step of searching for whether there is data corresponding to the received SN by the standby SAAL and requesting retransmission of the corresponding data to the active SAAL when there is no corresponding data; And a data transmission step of the active SAAL searching for the corresponding data and transmitting the data to the standby SAAL. The method of claim 1, The redundant data includes a SN, a data pointer, and SAAL connection information. In the SAAL duplication method consisting of an active SAAL and a standby SAAL, A message receiving step in which each SAAL receives a message from an upper or lower layer; A message processing step in which each SAAL processes the received message; A duplication step wherein each SAAL maintains the same duplication data through a duplication window; A transfer determination step of determining whether or not the active SAAL is to be transferred; And a standby step in which the standby SAAL replaces the function of the active SAAL when the active SAAL is switched. The method of claim 3, wherein The redundancy step, An SN transmission step in which the active SAAL transmits an SN to the standby SAAL through a redundant window; A retransmission request step of searching for whether there is data corresponding to the received SN by the standby SAAL and requesting retransmission of the corresponding data to the active SAAL when there is no corresponding data; And a data transmission step in which the active SAAL retrieves the corresponding data and transmits the data to the standby SAAL.

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