KR20030003613A - Uni Directional Switching Control Method of Synchronous Digital Hierarchy System - Google Patents

Abstract

PURPOSE: A method for controlling unidirectional protection of an SDH(Synchronous Digital Hierarchy) transmission system is provided to set up a new working line through bidirectional production upon failure alarm deact of a line set as a working line during communication through unidirectional protection, so as to prevent a fatal defect occurring when an operator detaches an optic/electric interface unit to which the working line is connected by mistake. CONSTITUTION: The first unit and the third unit are set in working state, and the fifth line and a sixth line are set as working lines(S1). If a failure alarm of the fifth line is forcibly deacted by an operator(S2), an alarm manager of the second system transmits a deact alarm notifying the deact of the failure alarm of the fifth line to an alarm manager of the first system(S3). When the deact alarm is generated, a failure alarm of the sixth line set as the working line is deacted(S4). An eighth line is set as a working line by the protection of a switching manager of the second system, and at the same time, a seventh line is set as a working line by the protection of a switching manager of the first system(S5). And the fifth line and the sixth line in which the failure alarms are deacted are converted to protection lines at the same time(S6).

Description

Unidirectionalal Switching Control Method of Synchronous Digital Hierarchy System

The present invention provides a new working line through two-way switching when a fault alarm is detected in a line set as a working line when communicating through a unidirectional switching between synchronous digital hierarchy (SDH) transmission systems. A unidirectional switching control method of a synchronous digital hierarchy transmission system to be set.

Recently, with the advent of broadband information networks, data transmission devices have developed into synchronous transmission networks. Accordingly, synchronous digital hierarchies and synchronous optical networks (SONET) have been developed based on the present invention. An optical transmission device is used.

In general, the SDH transmission system providing the SDH scheme provides an automatic protection switching function to ensure the stability of the transmitted data.

Here, the automatic protection switching function means that a transmitting network element transmits data to a receiving network element through two transmission paths, and the receiving network element switches to a better transmission path among the two transmission paths. It means receiving and processing data transmitted from the transmission path.

In this case, the transmission path for receiving data is called a working line, and the transmission path that does not receive data is called a protection line.

1 is a conceptual diagram illustrating a transmission line switching method between a conventional SDH transmission system having such an automatic protection switching function.

As shown, each SDH transmission system 100 includes a plurality of optical / electric conversion interface units 110 and 120 as network elements for interfacing with optical cables, and each optical / electric conversion interface unit 110 and 120. ) Are provided with transmission and reception ports 111 and 121, and transmit and receive lines are respectively connected.

In this case, the loss of signal (LOS), the loss of frame (LOF), the signal degraded (LOF), etc. may occur in each line according to the transmission state, and thus data may not be transmitted normally. A problem may occur in the network device, that is, the photoelectric conversion interface unit 110 or 120 itself, and thus data may not be transmitted.

As described above, according to a failure that occurs because data is not normally transmitted, the alarm manager 130 divides the failure level in association with the control unit 101, generates a failure alarm according to the level, and the switching manager 140. ) Determines that the line with the lower alarm among the fault alerts generated is a better line and transfers data to the line.

Therefore, at this time, the line receiving the data becomes the working line and the other side becomes the protection line. The switching of the line at the receiving side is called receiving switching.

However, even though such a fault alarm is very important, if a fault alarm continues to occur, the actual number that the operator does not want to monitor the fault alarm may actually occur, which is called an alarm deact.

When an alarm of a specific line is deacted in this way, the transmission state of the line is not known, so the deactivated line becomes a protection line and another line becomes a working state to receive data.

On the other hand, a transfer scheme for data transmission between SDH transmission systems can be divided into unidirectional switching and bi-directional switching. In the case of bidirectional switching, transmission and reception switching between SDH transmission systems, that is, between SDH transmission systems This means that all of the reception switching is performed, and unidirectional switching means that only the reception switching of one SDH transmission system is performed.

FIG. 2 is a block diagram illustrating a one-way transfer method between SDH transmission systems when a failure alert operates, and FIG. 3 illustrates a problem occurring when an operator forcibly deactivates a failure alert of a working port. It is a block diagram.

As shown in FIG. 2, a first SDH transmission system (hereinafter, abbreviated as first system, 100) may include a first optical-to-electrical conversion interface unit (hereinafter abbreviated as first unit, 110) and a second optical fiber. A full conversion interface unit (hereinafter abbreviated as second unit, 120) is provided, and each unit has transmission and reception ports 111 and 121, respectively.

A second SDH transmission system (hereafter abbreviated as second system, 200) that communicates with the first system may include a third optical / electric conversion interface unit (hereinafter abbreviated as third unit, 210) and a fourth optical link. A full conversion interface unit (hereinafter abbreviated as fourth unit 220) is provided, and each unit has transmission and reception ports 211 and 221, respectively.

In addition, the transmission and reception ports 111 of the first unit 110 are connected to the reception and transmission ports 211 of the third unit 210 by the fifth line 301 and the sixth line 302. The transmission and reception ports 121 of the two units 120 are connected to the reception and transmission ports 221 of the fourth unit 220 by the seventh line 303 and the eighth line 304.

At this time, since the fifth line 301 and the sixth line 302 connected to the transmission / reception ports 111 and 211 of the first unit 110 and the third unit 210 are set as working lines, It must be transmitted and received via the fifth and sixth lines 301 and 302.

However, FIG. 2 illustrates a case of performing a unidirectional transfer in which data is transmitted from the first system 100 to the second system 200. Therefore, the receiving ports 111Rx and 121Rx of the first system 100 Instead of performing the reception switching, only the reception ports 211Rx and 221Rx of the second system 200 perform the reception switching.

Therefore, although the fifth line 301 and the sixth line 302 are set to the working state, the line to which data is actually transmitted is the fifth line 301, and the sixth line has only a pass formed in the working state. No data is sent.

However, as shown in FIG. 3, if the operator detects a failure alert of the reception port 211Rx of the third unit 210 set as the working port, the second system 200 may fail the fifth line 301. Since the degree cannot be determined, the fifth line 301 is switched to the protection state and the eighth line 304 is set to the working state.

Therefore, the data transmitted through the fifth line 301 is transmitted to the second system 200 through the eighth line 304.

However, due to this, the operator may mistake a line connected to the first unit 110 and the third unit 210 as the protection line. Because the sixth line 302 is a line for reception switching of the first system 100, when operating in a unidirectional switching method, when the reception of the second system 200 is performed, the sixth line 302 transmits the transmission. This is because only the path is set as the working line and no data is actually transmitted.

Therefore, the operator does not consider the sixth line 302, and determines that the first unit 110 and the third unit 210 do not directly affect the data transmission to perform maintenance or the like on the first system. There is a possibility to hernia the first unit 110 or the third unit 210 from the 100 or the second system 200.

In this case, the sixth line 302 connected to the receiving port 111Rx of the first unit 110 and the transmitting port 211Tx of the third unit 210 is actually set as a working line, but the first unit is ignored. As a result of dismounting the 110 or third unit 210, the first system 100 has a fatal hardware defect that causes the receiving line to be lost.

As described above, when a failure of a specific line set as a working line is detected during communication through a unidirectional transfer between the systems 100 and 200, the unit connected to the line may be misused by an operator for maintenance or the like. There is a problem that can cause a fatal defect in the system (100, 200) by hernia.

The present invention has been devised to solve these problems, and when communicating between SDH transmission systems through unidirectional switching, a method for setting a new working line through bidirectional switching when a fault warning of a line set as a working line is detected. The purpose of the present invention is to prevent fatal defects caused by an operator accidentally dismounting the optical / electrical interface unit to which the working line is connected, thereby minimizing the problems occurring in the failure alert detecting.

1 is a conceptual diagram illustrating a transmission line switching method between a conventional SDH transmission system having an automatic protection switching function.

FIG. 2 is a block diagram for explaining a one-way switching method between SDH transmission systems when a failure alert operates. FIG.

3 is a block diagram illustrating a problem that occurs when an operator forcibly deactivates a failure alert of a working port.

4 is a block diagram for explaining a one-way switching control method of the SDH transmission system according to an embodiment of the present invention.

Figure 5 is a flow chart showing the flow of the one-way switching control method of the SDH transmission system according to a preferred embodiment of the present invention.

In order to achieve the above object, the present invention provides a first SDH (Synchronous Digital Hierarchy) transmission system interconnected through a transmission line consisting of a plurality of transmission and reception line pairs, and the second SDH transmission system exchanges data with each other through unidirectional switching. When performing the operation, if the fault alarm of the working line of the transmission line is detected, the fault alert of the line forming a transmission and reception pair with the working line is also detected, and the line paired with the working line and the working line At the same time, switching to a protection line and setting a pair of transmission / reception lines other than the switched protection line as a working line.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

In addition, it should be noted that the same reference numerals are given to the same components, although belonging to different drawings for convenience of understanding.

4 is a block diagram illustrating a unidirectional switching control method of an SDH transmission system according to an exemplary embodiment of the present invention.

As shown, the first system 100 includes a first unit 110 and a second unit 120 as a network element for interfacing with an optical cable, and each unit 110 and 120 has a transmission / reception port ( 111 and 121 are installed.

Meanwhile, the second system 200 for communicating with the first system 100 includes a third unit 210 and a fourth unit 220 as network elements for the optical cable and the interface, and each unit ( Transmitting and receiving ports 211 and 221 are installed at 210 and 220.

At this time, the transmission port 111Tx and the reception port 111Rx of the first unit 111 are connected to the reception port 211Rx and the transmission port 211Tx of the third unit 210 by the fifth line 301 and the sixth line. 302, the transmit port 121Tx and the receive port 121Rx of the second unit 120 are connected to the receive port 221Rx and the transmit port 221Tx of the fourth unit 220. ) And the eighth line 304.

On the other hand, the first and second systems (100, 200) in conjunction with the control unit (101, 201) and the alarm manager (103, 230) for generating a fault alarm according to the transmission state of the line or the state of the unit, respectively, Switching managers 140 and 240 are included to determine the good lines according to the grade of the fault alert and switch the lines.

In addition, the first system 100 and the second system 200 operate under the control of the first system control unit 101 and the second system control unit 201 that control the interaction and data flow of the devices in the system.

5 is a flowchart illustrating a flow of a unidirectional switching control method of an SDH transmission system according to an exemplary embodiment of the present invention.

First, as in the situation of FIG. 2, the first unit 110 and the third unit 210 are set to the working state so that the fifth line 301 and the sixth line 302 are set to the working line ( Step: S1), if the fault alarm of the fifth line 301 is forcibly deacted by the operator (step: S2), the alarm manager 230 of the second system 200 is the fault alarm of the fifth line 301. Sends an alert to the alarm manager 130 of the first system (100) indicating that it is deactivated (step: S3).

The alert manager 130 of the first system 100 then generates a Detect alert such that the fault alert of the sixth line 302 paired with the fifth line 301 is detected.

When the alert is generated, the fault alert of the sixth line 302 which has been set as the working line is also detected (step: S4).

Accordingly, the eighth line 304 is set as the working line by the switching of the switching system 240 of the second system 200, and the protection line is changed by the switching of the switching manager 104 of the first system 100. The seventh line 303 is set as the working line (step S5), and the fifth line 301 and the sixth line 302 where the fault alert is detected are simultaneously switched to the protection line (step: S6).

Therefore, the first unit 110 and the third unit 210 are simultaneously switched from the working state to the protection state and the second unit 120 and the fourth unit 220 are set to the working state.

In this case, even if the user dismounts the first unit 110 and the third unit 210 set as protection for maintenance or the like, the transmission / reception line between the first system 100 and the second system 200 is the seventh line. Since 303 and the eighth line 304 are secured, no problem occurs.

That is, even if the fault alert of the fifth line 301, which is set as the working line, is switched to the protection line, the sixth line 302 constituting a transmission / reception pair is simultaneously connected to the protection line with the fifth line 301. Since it is set, new working lines are set in the seventh line 303 and the eighth line 304.

Therefore, even if the operator dismounts the first unit 110 or the third unit 210 set to the protection state, reception switching of the first system 100 is made through the seventh line 303 and the second system 200 is removed. ) Is transferred through the eighth line 304, so that data transmission and reception between the two systems is possible.

On the other hand, when the fifth line 301 from which the fault alert has been deactivated by the operator is switched back to the act state, the fault alert of the sixth line 302 constituting the transmission / reception pair is automatically switched back to the act state.

Although the preferred embodiments of the present invention have been described in detail above, those skilled in the art will appreciate that the present invention may be modified without departing from the spirit and scope of the invention as defined in the appended claims. It will be appreciated that modifications or variations may be made. Therefore, changes in the future embodiments of the present invention will not be able to escape the technology of the present invention.

As described above, according to the present invention, when communicating through the one-way switching between the SDH transmission system, when the fault alarm of the line set as the working line, the new working line is set through the two-way switching, the operator is connected to the working line It is a useful invention that has the advantage of preventing problems caused by fault detection by preventing fatal defects caused by accidentally dismounting the optical / electric interface unit.

Claims (3)

When the first SDH (Synchronous Digital Hierarchy) transmission system and the second SDH transmission system which are interconnected through transmission lines composed of a plurality of transmission and reception line pairs perform data exchange with each other through unidirectional switching, Converting the working line and the line paired with the working line into a protection line at the same time when a failure alert of a working line of the transmission lines is deacted; And setting another transmission / reception line pair as a working line in addition to the switched protection line. The unidirectional switching of the SDH transmission system according to claim 1, wherein when a failure alert of the working line is detected in the protection line switching step, a failure alert of a line forming a transmission / reception pair with the working line is also simultaneously detected. Control method. The SDH transmission system according to claim 1, wherein when the fault alarm of the line switched to the protection is switched back to Act, the fault alarm of the line constituting the line and the line pair is simultaneously switched to Act. One-way transfer control method.