KR0153949B1 - Cell Replication Internal Path Setting Method Using Virtual Path in Fully Distributed ATM Switching System - Google Patents

Abstract

The present invention relates to a cell replication internal path establishment method using a virtual path (VP) in a broadband integrated information network (B-ISDN) using an asynchronous transfer mode (Asynchronous Transfer Mode, ATM). A cell replication internal path setting method using a virtual path applied to an ATM system, comprising: a first step (100 to 105) for replicating an output cell at an input end; A second step (110 to 116) for replicating the output cell at the output side; A third step (120 to 127) for releasing output cell copy at the input terminal; And a fourth step (130 to 135) for releasing the output cell replication at the output terminal, thereby allowing the maximum control of the distributed control concept in the fully distributed ATM switching system to establish the cell replication internal path.

Description

Cell Replication Internal Path Setting Method Using Virtual Path in Fully Distributed ATM Switching System

1 is an explanatory diagram of cell replication in an ATM switching system to which the present invention is applied.

2 is a diagram illustrating a tree cell replication state in an ATM switching system to which the present invention is applied.

3 is a flow chart for output cell replication at the input side according to the present invention.

4 is a flow chart for output cell replication at the output side according to the present invention.

5 is a flowchart for canceling output cell replication at the input terminal side according to the present invention.

6 is a flow chart for canceling output cell replication at the output side according to the present invention.

The present invention relates to a cell replication internal path establishment method using a virtual path (VP) in a broadband integrated information network (B-ISDN) using an asynchronous transfer mode (ATM).

In a fully distributed system, cell replication control subjects are distributed on each ATM Local Subsystem (ALS), which requires a different method from centralized control.

The distributed control method is a method in which the control entity on each ALS has only information on a path connected to an ATM Central Subsystem (ACS) and thus does not recognize a connection shape with another ALS in the overall system level.

Therefore, in order for information transmission paths to be set up between different ALSs, information exchange between routing agents on each ALS is essential.

The reason for taking a decentralized method rather than a centralized path control method is that it is possible to easily expand the ALS system and to prevent bottlenecks caused by centralization, thereby enabling system size selection as needed.

Accordingly, an object of the present invention is to provide a cell replication internal path establishment method using a virtual path that can fully accommodate the concept of distributed control in a fully distributed ATM switching system.

In order to achieve the above object, the present invention provides a method for setting a cell replication internal path using a virtual path applied to a fully distributed ATM switching system, wherein the same ALS (ATM) is received by receiving a cell replication setting request for an output terminal n. In case of intra cell replication, which is a cell replication in Local Subsystem, set the output port bit on the input ALS for output terminal n.If inter cell replication, which is a cell replication between other ALSs, request setting for output terminal n. Transmitting a cell replication state on the input terminal ALS, and setting an input terminal ALS output port bit to perform a cell replication to the selected ACS at the output terminal upon receiving a setting request for cell replication to the selected ACS; On receipt of the cell replication setup request for output n, set the ALS output port bit for output n and check the incoming cell replication link status to determine the specific ACS for cell replication if the duplicated cell is not coming from either ALS. Selecting, setting an output port bit of the selected ACS, and requesting to set the selected ACS to perform cell replication with the ACS selected as the input side ALS if the selected ACS is not currently performing cell replication; Receiving the request signal for releasing output stage n resets the output port bit for output stage n if intra cell replication, requests release with ALS for output stage n if inter cell replication, and all output stages Resetting all of the output port bits on the input end side ALS when receiving a request to temporarily release the data, and resetting the corresponding output port bits of the input end side ALS upon receiving the output port bit reset request to the corresponding ACS; And upon receiving a cell replication cancel request for output terminal n, resets the output port bit for output terminal n on output side ALS, and resets the cell replication output port bit of the corresponding ACS if cell replication is not performed at output side ALS. And if the ACS is not performing cell replication, a fourth step of requesting the reset of the output port bit to release the cell replication to the ACS to the input terminal ALS.

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

1 is a cell replication explanatory diagram in an ATM switching system to which the present invention is applied, and cell replication path setting is a method of establishing a tree-type path between one input terminal into a system and a plurality of output terminals to the outside of the system. Means that.

Each branch of this tree represents a cell replication point within the system, and the cell replication point performs a function of copying input information to each connection branch.

Therefore, the ATM information cell flowing into the input terminal is copied along each tree path, and is duplicated every time the cell replication point passes, and thus, the information cells of the same input terminal can be transmitted from multiple output terminals.

Each cell clone point has a random L output port, and has bitmap data for cell duplication. It decides whether to duplicate a cell to a specific output port.

Each output port is connected to an input / output terminal through an input / output link or an ALS 1 and an ACS 2 are connected through a cell replication link.

Inside the system, there are any natural number N (1) ALS cell replication points, and any number M ACS cell replication points (2).

The ALS cell replication point 1 and the ACS cell replication point 2 take the form of a full mesh connection so that all ALS 1 can establish a cell replication path with any other ALS 1.

Each link can transmit bidirectional information. If cell unit (packet consisting of a limited number of bytes) information flows from the input terminal, each cell replication point copies the received packet according to the bitmap information and transmits it to each link.

2 is a diagram illustrating a tree cell replication state in an ATM switching system to which the present invention is applied, in which an information cell of an input terminal 10 requires cell replication by the same ALS cell replication point for an output terminal 1 (11). Since it is intra cell replication, it is necessary to set the bit of the ALS1 (12) output port for the output terminal 1 (11).

In the case of output stages 2, 3 and 4 (17 to 19), other ALS cell replication points must be used, so they go through ACS. This is called inter cell replication.

As shown in FIG. 2, the link from the input ALS to the ACS is called the originating cell replication link, and the link from the ACS to the output ALS is called the destination cell replication link.

For inter-cell replication, cell replication bit setting or resetting is performed on the following principle.

First, all the cell replication information update process is started by first sending a signal requesting a specific purpose to the control entity of the input side ALS. The input-side control entity needs to check whether cell replication to all ACSs is made.

Second, the replication cell flowing into the output side ALS is made in only one of the L ACS. The reason for this is to exclude a state in which two or more of the same information flows into the output side ALS.

Third, the output-side control entity should have all the information about the cell replication status of the ACS. The reason is that when more than one output is connected to the ALS, the ACS cell replication status must be analyzed to request cell replication from one ACS. The method for ACS selection is not considered here and assumes the application of the band management algorithm on the link.

Fourth, the cell replication bit setting from the input ALS to the ACS is always required by the output-side control entity requesting the ACS to set the cell replication bit to the ACS selected as the input ALS.

Fifth, when there is no output terminal connected to the output side ALS, the output side control entity resets the bits of the ACS performing cell replication to the output ALS. This releases the incoming cell replication link that has been occupied immediately if there is no need for cell replication in the output ALS.

Sixth, when the control subject on the output side ALS resets a specific bit of the ACS, it continuously checks the cell replication status on the ACS. Requires a reset of the ALS cell replication output port bit to abort. The reason is to release the outgoing cell replication link that was occupied immediately if the ACS did not perform cell replication.

Seventh, the information cell flowing into the system from the input stage is automatically discarded at the cell replication point if cell replication is not performed at the input side ALS. The prevention of information cell inflow into the system at the input end is not covered here.

Eighth, it is assumed that all cell replication bitmaps are always reset before the system internal cell replication path is set for one input terminal and the first registered output terminal.

It is assumed that the ninth control entity on all ALSs always share the cell replication output port bitmap information of the ACS. This can be guaranteed by the database system.

3 is a flow chart for the output cell replication at the input side according to the present invention. The controlling entity on the input side ALS is waiting for two request signals. In the standby state, when receiving a signal requesting the update of the system internal cell replication bitmap information for the output terminal n (100), in the case of intra cell replication, the output terminal n is set on the input terminal ALS because the output terminal n is set on the input terminal ALS. This is done by setting the port bits (102). In the case of inter cell replication, the cell replication status on the output terminal ALS is transmitted (103).

Input port ALS output port to perform cell replication to the selected ACS at the output stage when receiving a signal requesting bit setting of the output port of the ALS for cell replication to the ACS selected by the control agent of the output ALS in the standby state (104). Set the bit (105).

Figure 4 shows a flow chart for output cell replication at the output side according to the present invention.

In the standby state, when the control agent on the output side ALS receives the cell replication setup request for the output terminal n (110), it sets the ALS output port bit for the output terminal n (111), and the incoming cell replication link status and the outgoing cell replication link status. Check (112).

First, if the cloned cell is not introduced from any one ALS by checking the state of the incoming cell replication link, the specific cell is selected by applying the destination cell replication link band management method (113). It is important to note that ACS should be selected so as not to overload specific ACS according to ACS cell replication.

When the ACS is selected, the output port bit of the selected ACS is set (114), and the current cell replication bitmap of the selected ACS is analyzed to check whether cell replication is already performed (115). If the current cell replication is being performed, return to the standby state.If the current cell replication is not being performed, the control agent of the input ALS is requested to set the cell replication output port bit of the ALS to perform the cell replication with the selected ACS. A signal to transmit is transmitted (116).

5 shows a flowchart for canceling output cell replication at the input side according to the present invention.

In the standby state, when the control entity of the input side ALS receives a request signal for releasing output stage n (120), if it is intra cell replication, it resets the output port bit for output stage n (122). In the case of duplication, the release request signal is transmitted to the control entity on the output side ALS (123).

When the input end control entity receives a request signal for temporarily releasing all output stages in the standby state (124), all output port bits on the input side ALS are reset (125).

When the output port bit reset request signal to the corresponding ACS is received in the standby state (126), the corresponding output port bit of the input side ALS is reset (127).

6 shows a flowchart for canceling output cell replication at the output side according to the present invention.

When the control agent of the output side ALS receives the cell replication cancel request signal for the output terminal n (130), it resets the output port bits for the output terminal n on the output side ALS (131), and continues the cell replication state on the ALS and the ACS. Check (132).

First, if cell replication is not performed at the output side ALS, the cell replication output port bit of the ACS performing cell replication to the output side ALS is reset (133). If the ACS is not performing cell replication (134), it requests the input terminal ALS to reset the output port bit of the input side ALS to release cell replication to the ACS (135).

The present invention operating as described above has the effect of maximizing the concept of distributed control in a fully distributed ATM switching system and establishing an internal path for cell replication.

Claims (1)

In the method of setting up a cell replication internal path using a virtual path applied to a fully distributed ATM switching system, an intra (cell replication) within a same ALS (ATM Local Subsystem) is received by receiving a cell replication setup request for an output terminal n. Intra) In case of cell replication, set the output port bit on input terminal ALS for output terminal n.If it is inter-cell replication, which is cell replication between other ALS, request setting for output terminal n, and transmit cell replication status on input terminal ALS. A first step (100 to 105) of setting an input ALS output port bit to perform cell replication to a selected ACS at an output terminal upon receiving a setting request for cell replication to a selected ACS; On receipt of a cell replication setup request for output n, set the ALS output port bit for output n, check the incoming cell replication link status, and specify the specific ACS for cell replication if the duplicated cell is not coming from either ALS. The second step (110 to request the setting of the output port bit of the selected ACS and setting the selected ACS to perform the cell replication to the ACS selected as the input side ALS if the selected ACS is not currently performing cell replication). 116); On receipt of the request signal for releasing output n, it resets the output port bit for output n if intra cell replication is required, and requests release with ALS for output n if inter cell replication, A third step (120 to 120) of resetting all output port bits on the input end side ALS upon receiving a request to release temporarily, and resetting the corresponding output port bits of the input end side ALS upon receiving a request to reset the output port bits to the corresponding ACS. 127); And upon receiving a cell replication cancel request for output terminal n, resets the output port bit for output terminal n on output side ALS, and resets the cell replication output port bit of the corresponding ACS if cell replication is not being performed at output side ALS. And a fourth step (130 to 135) requesting the reset of the output port bits to release the cell replication to the corresponding ACS if the ACS is not performing cell replication. ) A method for establishing a cell replication internal path using a virtual path in a switching system.