KR20100066276A - Method and apparatus for equal opportunity protection switching in transport network - Google Patents

Abstract

PURPOSE: A method and a device for equal opportunity protection switching in a transport network are provided to return the state of a preliminary channel compulsorily to normal if the failure of the specific working channel occurs over the predetermined time. CONSTITUTION: The first and second transmitting devices(100,200) transmit and receive a traffic. If N operating channels(301~30N) are normal state, the traffic between transmit devices is transferred. A preliminary channel(400) switches the traffic of the working channel which failure occurred. A control unit(110) switches a signal of a failure occurrence channel to the preliminary channel. If a failure state of the failure occurrence channel is normally canceled, the control unit cancels the switch to the preliminary channel in normal.

Description

Method and apparatus for equal opportunity protection switching in transport network

The present invention relates to a 1: N protection switching scheme in a transmission network. More particularly, the present invention relates to a transmission network that provides equal opportunities for protection switching to other operating channels even if a failure of a specific operation channel continues. The present invention relates to a method and apparatus for equal opportunity protection switching.

The present invention is derived from the research conducted as part of the IT growth engine technology development project of the Ministry of Knowledge Economy and the Ministry of Information and Communication Research and Development. [Task management number: 2008-S-010-01, Task name: Multi-layer optical network control platform technology Development].

In the conventional transport network, the 1: N protection switching scheme is composed of one spare channel and N operating channels to deliver network service traffic. In this case, one spare channel is used as a channel capable of transferring traffic of the corresponding operating channel when a failure occurs in any of the N operating channels. If a spare channel is available and a failure occurs in one of the N management channels, the traffic of the channel is switched to one spare channel.

However, in the conventional 1: N protection switching scheme, when two or more operating channels fail simultaneously, only traffic of one operating channel can be protected. In addition, one operating channel traffic switched to a spare channel has a problem of delivering the corresponding traffic by continuously occupying the spare channel until the original failed management channel is repaired and repaired. That is, there is a problem in that traffic of other operating channels cannot be protected.

Since the transmission network must be able to transmit a lot of information most quickly and accurately, it is important to transmit the transmission and reception data between network elements as the original traffic without any obstacles. It is an important factor in evaluating the most basic and essential functions.

However, in the conventional 1: N protection switching scheme, as described above, when the device of the protected recovery operation channel cannot be repaired and repaired, the reserved operation channel is continuously occupied. This makes it impossible to protect even if a failure occurs in other operating channels, causing a problem of deteriorating network survivability and service reliability of the transport network.

Therefore, in the present invention, if a failure of a specific operating channel occurs for a predetermined time in the equal opportunity protection switching method of the transmission network, the state of the reserved channel is forcibly returned to normal to provide an equal protection switching function to other operating channels. The present invention relates to a method and apparatus for equal opportunity protection switching in a transmission network.

In addition, the present invention relates to a method and apparatus for equal opportunity protection switching in a transmission network that continuously informs an operator of a failure state of an operation channel so that a response can be performed more quickly and accurately.

According to a first aspect of the present invention, there is provided a means for solving the above problems, comprising: monitoring a state of each of the N operating channels; Switching the traffic of the failed management channel to a spare channel when detecting a failed operation channel among N operating channels; And if the failure state of the failed operation channel continues abnormally, forcibly returning the failed operation channel and the spare channel to a normal state.

Forcibly returning the spare channel to a normal state may include counting a failure occurrence time of the failed operation channel; And when the failure occurrence time reaches the second time, confirming that the failure occurrence state of the failed operation channel continues abnormally and forcibly returning the spare channel to the normal state.

The step of forcibly returning the spare channel to the normal state may further include informing the operator that manual repair and repair of the failed operating channel is required when the failure time reaches the second time.

According to a second aspect of the present invention, there is provided a means for solving the above problems, comprising: an equal opportunity timer for detecting and notifying that a failure state of a failed operation channel continues abnormally; By monitoring the state of each of the N operating channels, if a failure of the operating channel is detected, the transfer to the spare channel is requested, and if the failure state of the failed operating channel continues abnormally forced to switch to the spare channel. N operating channel units to release; And in response to a request for switching to the spare channel of the N management channel units, transfer the traffic of the failed management channel to the spare channel, and if the failure state of the failed management channel continues abnormally, the spare. An equal opportunity protection switching device in a transmission network including a spare channel unit forcibly returning a channel to a normal state is provided.

As described above, the method and apparatus for equal opportunity protection switching in the transmission network of the present invention detects abnormally occupying the reserved channel due to a failure of a specific operating channel for a predetermined time, and forcibly returns to the normal state of the reserved channel. .

Therefore, it is possible to provide equal protection switching opportunities to the remaining operating channels regardless of whether a specific operation channel continues to fail.

In addition, the operator is informed of the information on the operation channel that performed the transfer, whether or not to release the transfer, and the information on the operation channel that continuously fails, so that the operator can respond to the operation more quickly and accurately.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, in describing in detail the operating principle of the preferred embodiment of the present invention, if it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

In addition, when a part is said to "include" a certain component, this means that it may further include other components, except to exclude other components unless otherwise stated.

Hereinafter, for convenience of description, a transmission device of a transmission system will be described as an example of an equal opportunity protection switching device in a transmission network.

1 is a diagram illustrating a transmission system according to an embodiment of the present invention.

Referring to FIG. 1, the transmission system is a basic network element, and the first and second transmission apparatuses 100 and 200 for transmitting and receiving traffic, and N operating channels 301 for transmitting traffic between transmission apparatuses in a steady state. 30N), and a spare channel 400 that transfers the traffic of the failed management channel (for example, 301) to transfer.

Each transmitter 100 (eg, 100) monitors whether each of the N operating channels 301 to 30N has a failure, and thus a signal of a failed operating channel (hereinafter, a failed channel (for example, 301)). Is switched to the spare channel 400, if the failure state of the failure channel 301 is normally released, the transfer to the reserve channel 400 is released normally, the failure state of the failure channel 301 continues abnormally When the control unit 110 forcibly cancels the transfer to the spare channel 400, the bridge and the selector 520 for transmitting and receiving signals to and from the counterpart transmission apparatus 200 through the N operating channels 301 to 30N and the spare channel 400. It is configured to include).

In this case, the spare channel 400 may be used as a traffic transmission channel of the network when the N management channels 301 to 30N operate normally without a failure or when the spare channel is not used.

2 is a view showing in more detail the control unit according to an embodiment of the present invention.

Referring to FIG. 2, the controller 110 of the present invention detects and notifies a failure tolerant state of a failure channel (for example, 301) that is normally released, a wait to ratio (WTR) timer 510 and a failure occurrence channel. The equal opportunity timer 520 for detecting and notifying that the failure state of 301 is abnormally released and monitors the states of each of the N operating channels 301 to 30N, and when the failure channel 301 is detected, is reserved. N operating channel units 531 to release the switching to the spare channel 400 when the switching to the channel 400 is requested and the failure occurrence state of the failure channel 301 is normally released or the failure occurrence state continues abnormally. 53N), in response to a request for the transfer of the N operating channel units 531 to 53N to the spare channel 400, the signal of the failure channel 301 is transferred to the spare channel 400, and the failure channel 301 is transmitted. ) Is off normally or the status is unstable. If it continues, the reserve channel unit 540 for returning the reserve channel 400 to the normal state, and detects the operating state of the N operating channel unit (531 ~ 53N) and the reserve channel unit 540 to notify the operator It is configured to include a status notification unit 550.

3 is a view for explaining a method of operating a control unit according to an embodiment of the present invention.

First, the controller 110 performs an initialization operation to initialize the WTR timer 510, the equal opportunity timer 520, and a failure flag value indicating whether a failure has occurred (S301).

The N operation channel units 531 to 53N perform a failure occurrence check on the management channel 301 to 30N managed therein (S302).

As a result of the check in step S302, if there is no operation channel part that detects a failure (S303), the failure occurrence flag value is maintained as 'False' (S304), and the N operation channel parts 531 to 53N reenter in step S302. Repeat fault checks.

On the other hand, when a specific operation channel unit (for example, operation channel unit 1 531) detects a failure (S303), the failure flag value is set to 'True' (S305), operation channel unit 1 (531) ) Performs 1: N protection switching to switch its traffic to the spare channel 400 (S306).

Even after the 1: N protection switching is performed, if the operation channel unit 1 531 continuously detects a failure occurrence and the failure occurrence flag value remains 'True' (S307), the WTR timer 510 is initialized in response thereto ( S308). In addition, the status notification unit 550 notifies the operator that a 1: N protection switching from the operation channel unit 1 531 to the spare channel unit 540 is performed because a failure occurs in the operation channel unit 1 531 (S317).

On the other hand, if the operation channel unit 1 531 detects a failure release and changes the failure flag value to 'False' (S307), the WTR timer 510 counts the failure release time of the failure management channel unit 531. The process starts (S309).

When the failure release state of the operation channel unit 1 531 lasts for the first time and counting of the WTR timer 510 is completed (that is, when the failure occurrence state of the operation channel unit 1 531 is normally released) (S310). The operation channel unit 1 531 and the spare channel unit 540 return to the normal state to release 1: N protection switching (S311), and notify the operator that the failure of the operation channel unit 1 531 is released (S317). ).

In the present invention, at the same time as performing the procedure of step S307 to step S311, it also performs a procedure for providing an equal protection switching function.

To this end, when 1: N protection switching is performed in which traffic of the operation channel unit 1 531 is switched to the spare channel unit 540, the equal opportunity timer 520 starts counting the time of occurrence of failure (S312).

Before the counting of the equal opportunity timer 520 is completed (S313), 1: N protection switching is released by step S311 so that the operation channel unit 1 531 and the spare channel unit 540, which have failed, are in a normal state. If returned to (S314), the equal opportunity timer 520 is initialized (S315). However, if the operating channel unit 1 531 and the spare channel unit 540 that have failed maintain the 1: N protection switching state (S314), the equal opportunity timer 520 continues to count the time of occurrence of failure (S312). ).

When the failure occurrence state of the operation channel unit 1 531 lasts for a second time and counting of the equal opportunity timer 520 is completed (that is, when the failure occurrence state of the operation channel unit 1 531 continues abnormally) ( S313), the 1: N protection switching is forcibly released so that the spare channel unit 540 is forced to return to the normal state so as to provide another 1: N protection switching opportunity to other operation channel units 132 to 53N (S316). . In addition, the status notification unit 550 notifies the operator of the need for manual repair and repair of the operation channel unit 1 531 because the failure of the operation channel unit 1 531 persists (S317).

4 is a flowchart illustrating an equal opportunity protection switching method according to an embodiment of the present invention over time.

In FIG. 4, for the sake of convenience of explanation, the equal opportunity protection switching method of the present invention is the normal operation channel unit 1 531, the operating channel unit N 53N, and the spare channel unit 540 all in normal states (S411, S412, S413). It is assumed that the WTR timer 510 and the equal opportunity timer 520 are started in the initialization states S414 and S415.

When the operation channel unit 1 (531) detects the occurrence of a failure (S421), the spare channel unit 540 performs a 1: N protection switching to transfer the traffic of the operating channel unit 1 (531) (S422), The equal opportunity timer 520 starts counting the occurrence time of the failure of the operation channel unit 1 531 (S423).

If the failure of the operation channel unit 1 531 is released before the counting of the equal opportunity timer 520 is completed (S424), the WTR timer 510 starts counting the failure release time (S425).

When the failure release time of the operation channel unit 1 531 becomes the first time and counting of the WTR timer 510 is completed (S426), the WTR timer 510 is reinitialized (S427) and the reserve channel unit 540. Releases the 1: N protection transfer and returns to the normal state (S428). Then, the traffic of the operation channel unit 1 531 delivered to the spare channel unit 112 is returned to the original operation channel unit 1 531, and the operation channel unit 1 531 is also returned to its normal state (S429). The opportunity timer 520 is also initialized in response (S430).

In this state, when the operation channel unit 1 531 detects a failure again (S431), the spare channel unit 540 performs 1: N protection switching (S432), and the equal opportunity timer 520 generates a failure time. Start counting again (S433).

If the failure of the operation channel unit 1 531 is released while the equal opportunity timer 520 counts the failure time (S434), the WTR timer 510 counts the failure release time (S435), before counting is completed. If a failure occurs again in the operation channel unit 1 (531) (S436), the WTR timer 510 is initialized again (S437).

As such, when the failure state of the operation channel unit 1 531 continues and the spare channel unit 540 and the operation channel unit 531 do not return to the normal state, another operation channel unit (for example, the operation channel unit N ( 53N)), it is not possible to perform 1: N protection switching from the operating channel unit N (53N) to the spare channel unit 540 (S439).

When the failure occurrence time of the operation channel unit 1 531 becomes the second time and counting of the equal opportunity timer 520 is completed (S440), when the equal opportunity timer 520 is initialized (S441), the spare channel unit ( The response 540 releases the 1: N protection switching and forcibly returns to the normal state (S442), and the operation channel unit 1 531 confirms that manual repair is required (S443).

In this state, the operating channel unit N 53N detects a failure (S444) and requests the 1: N protection switching to the spare channel unit 540, and the spare channel unit 540 manages the operating channel unit N 53N. In response to the 1: N protection switching request, the traffic of the operating channel unit N 53N can be switched and transmitted (S445). That is, the spare channel unit 540 performs 1: N protection switching to the other operating channel unit regardless of the failure state of the operating channel unit 1 (531).

Thus, in the present invention, even if the failure of the operation channel unit 1 (531) that performed the 1: N protection switching operation persists, when a certain time elapses, the 1: N protection switching is forcibly released, and the other operation channel unit is also 1: N protection switching. Allows you to perform an action.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and it is understood that various substitutions, changes, and changes can be made without departing from the technical spirit of the present invention. It will be apparent to those skilled in the art.

1 is a diagram illustrating a transmission system according to an embodiment of the present invention.

2 is a view showing in more detail the control unit according to an embodiment of the present invention.

3 is a view for explaining a method of operating a control unit according to an embodiment of the present invention.

4 is a flowchart illustrating an equal opportunity protection switching method according to an embodiment of the present invention over time.

Claims (4)

Monitoring the failure of each of the N operating channels to detect a failed operating channel, and switching traffic of the failed operating channel to a spare channel; And And if the failure state of the failed operation channel continues abnormally, forcibly returning the failed operation channel and the spare channel to a normal state. The method of claim 1, wherein the control unit Counting a failure occurrence time of the failed operation channel; And When the failure time reaches the second time, checking whether the failure state of the failed operation channel continues abnormally and forcibly returning the spare channel to a normal state. Protection transfer method. The method of claim 2, wherein the control unit And even notifying the operator that manual repair and repair of the failed operating channel is required. An equal opportunity timer for detecting and notifying that a failure state of a failed operation channel continues abnormally; By monitoring the state of each of the N operating channels, if a failure of the operating channel is detected, the transfer to the spare channel is requested, and if the failure state of the failed operating channel continues abnormally forced to switch to the spare channel. N operating channel units to release; And In response to a request for switching to the spare channel of the N operating channel units, traffic of the failed management channel is transferred to the spare channel, and if the failure state of the failed management channel continues abnormally, the spare channel. Equal opportunity protection switching device in a transmission network comprising a spare channel for forcibly returning to a normal state.

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