KR100236957B1 - Multicast channel allocation method in access network - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

The present invention relates to a multicasting channel establishment method in an access network.

2. The technical problem to be solved by the invention

In the present invention, a multicasting channel is established in an access network having limited bandwidth by using a specific virtual path as a multicasting dedicated channel to accommodate more multicasting channels in a ring in an access network employing a load-sharing duplex ring. To provide a way.

3. Summary of Solution to Invention

The present invention provides a multicasting channel setting method in an access network for connecting a geographically dispersed asynchronous delivery mode end-point subscriber group to an asynchronous delivery mode service node. A first step of setting one multicasting channel through the multicasting setting information after determining a; And a second step of adding a leaf party belonging to the set multicasting channel to set a channel of the corresponding leaf.

4. Important uses of the invention

The present invention is used for establishing a multicasting channel in ATM.

Description

How to Set Up Multicasting Channels in an Access Network

The present invention provides a geographically distributed Asynchronous Transfer Mode (ATM) endpoint group in a fiber-to-the-home / fiber-to-the-building (FTTH / FTTB) environment. A multicasting channel establishment method in an access network for accessing an ATM service node.

In general, multicasting in a subscriber access network using ATM transmits the same information from one transmitter to multiple receivers through a point-to-multipoint virtual channel. At this time, the point-to-multipoint virtual channel to be preset before transmitting the actual information between the transmitting side and the receiving side should be appropriately designed according to the topology of the physical network.

Conventionally, a multicasting channel establishment method in a subscriber access network using ATM uses a star network configuration and a ring network configuration such as unidirectional, unidirectional self-healing, and bidirectional double ring.

However, as a conventional multicasting channel setting method, a limited ring bandwidth is used when multicasting is performed in the form of a mesh point-to-point virtual channel between each ATM multi-multiplexer and an ATM service node. There was a problem of poor efficiency.

In order to solve the above problems, the present invention provides a limited bandwidth by using a specific virtual path as a multicasting dedicated channel to accommodate more multicasting channels in a ring in an access network employing a load sharing duplex ring. An object of the present invention is to provide a multicasting channel setting method in an access network having a network.

1 is a structural diagram of an asynchronous delivery mode multi-multiplexer and an access network to which the present invention is applied.

2 is a structural diagram of the asynchronous delivery mode multi-duplexer 11 of FIG.

3 is a structural diagram of the asynchronous delivery mode multi-multiplexer 12 of FIG.

4 is a structural diagram of a ring connection function 121 for the double ring configuration of FIG.

5A and 5B are flowcharts of one embodiment of a method for establishing a multicasting channel in a load sharing bidirectional double ring according to the present invention;

* Explanation of symbols for the main parts of the drawings

11, 12: asynchronous delivery mode multi-reverse multiplexer

13: asynchronous delivery mode service node

In order to achieve the above object, the present invention provides a multicasting channel setting method in an access network for connecting a geographically dispersed asynchronous delivery mode terminal subscriber group to an asynchronous delivery mode service node. A first step of setting one multicasting channel through the multicasting setting information after determining a path for the casting channel to pass through; And a second step of adding a leaf party belonging to the set multicasting channel to set a channel of the corresponding leaf.

Hereinafter, with reference to the accompanying drawings will be described an embodiment according to the present invention;

1 is a structural diagram of an asynchronous delivery mode multi-multiplexer and an access network to which the present invention is applied.

The access network to which the multicasting algorithm of the present invention is applied comprises an ATM multi-decoder 11, 12 and a communication link for connecting them to the ATM service node 13. It is composed of ATM multi-reversals 11 and 12, which are unit nodes, point-to-point communication links for connecting these multi-reverse multiplexers 11 and 12 to ATM service nodes 13, and communication links in a ring topology form. I use it.

The ATM multiplex multiplexer 11 is an ATM device that performs the statistical multiplex multiplex function of an N * 1 valid ATM cell. Here, N is an integer greater than 1 and less than or equal to 8, and varies depending on the traffic aggregation ratio.

Therefore, the ATM multi-decoder 11 can be classified into two types according to the type of access to the ATM service node 13. It is an ATM multi-duplexer 11 directly connected to an ATM service node 13 via a 155 Mbps synchronous transfer mode-1 (STM-1) class fiber, and a load sharing bidirectional using a 155 Mbps STM-1 class fiber. It can be divided into an ATM multi-duplexer 12 connected to a double ring.

As shown in FIG. 2, the ATM multi-determinant multiplexer 11 has an ATM layer termination 111-2 including an STM-1 physical layer termination 111-1 and an ATM connection lookup table. And a line connection function (LT) line 111 having a function of controlling a multicasting channel by the connection control unit 113, and a multiple and demultiplexing function, a copying function, and a routing function of a valid ATM cell. And a connection controller 113 for reading, writing, and updating the ATM connection lookup table according to the control command of the ATM service node 13.

ATM multiplex multiplexer 11 has a physical layer function, ATM layer function, ATM cell multiplexing and demultiplexing function, cell routing function, and connection control function to perform the multiverse multiple function of a typical ATM cell, ATM service node A connection control function for reading / writing / updating a connection search table is performed in accordance with the connection control command of (13). In addition, when an ATM cell having a specific Virtual Path Identifier (VPI) is introduced from the ATM service node 13 to support the multicasting function, the cell is transferred to the subscriber side line access function 111. Has the function of copying

As shown in FIG. 3, the ATM multi-reversible multiplexer 12 further includes a ring connection function (RT) 121 for a double ring connection in addition to the function of the ATM multi-reverse multiplexer 11. Here, the ring connection function unit 121 has a multicasting channel control function by the connection control unit 113.

In order to support the multicasting function, the ATM multi-reverse multiplexer 12 transfers the corresponding cell to the subscriber side line access unit 111 when an ATM cell having a specific virtual path identifier comes from a ring connected to the ATM service node 13. ) And the cell simultaneously radiate to the ring in the direction of flow.

The ATM service node 13 is a line connection function (LT) line 111, ring connection function 121, ATM endpoint subscriber and transparent and dynamic ATM virtual channel configuration and duplexing Signal / connection control unit 131 for efficient load sharing and ATM switching unit 132 for connecting thereto. Here, the signal / connection control unit 131 collectively manages the multicasting channel in the access network.

The communication link may be classified into two types according to a method of connecting the ATM multi-duplexers 11 and 12 to the ATM service node 13.

This is a point-to-point communication link for connecting the ATM multi-duplexer 11 to the ATM service node 13 and a ring topology for connecting at least two ATM multi-duplexers 12 to the ATM service node 13. It consists of a form of communication link. Here, the physical characteristics of the communication link uses a 155 Mbps STM-1 class irrespective of the configuration.

The communication link in the ring topology is composed of a link in the left direction and a link in the right direction in order to connect adjacent ATM multi-reversal multiplexers 12, and the links at both ends are connected to the ATM multi-reversal through the ring connection function unit 121. It is connected to the functional unit 112.

The ring connection function unit (RT) 121 is composed of an input processing unit and an output processing unit. In the drawing, "401" is a reception connection search table, "402" is a transmission connection search table, "403" is a bypass / drop control unit, "404" is a header converter, "405" is a buffer, "406" is a 2 * 1 multiplex, "407" is an ATM layer receiver, "408" is an ATM transmitter, "409" is a physical layer receiver, and "410" Represents a physical layer transmitter, respectively.

The input processing unit multiplexes 2: 1 in the case of a valid cell registered in the connection table coming from the input links of both ends registered in the connection table, and inputs it to the ATM cell demultiplex function, and in the case of a cell not registered in the connection table. It has an optional control to pass through or discard the opposite link.

The output processor performs a function of broadcasting a cell output from the ATM cell multi-function unit at 1: 2 on the output link of both ends.

The cell broadcasted through the output links of both ends is outputted in the ring after header conversion only when the cell is registered in the connection table, and the other cells are discarded.

The multicasting algorithm according to the present invention is controlled by the circuit connection function unit 111 of the ATM multi-reverse multiplexer 11 and the ring connection function unit 121 of the ATM multi-reverse multiplexer 12, and the overall multicasting channel connection control The function is performed at the ATM service node 13.

Accordingly, in order to perform the multicasting function, the ATM multi-reversal multiplexer 112 in the ATM multi-reversal multiplexer 11 and 12 provides output port information necessary for cell copying. The function unit 121 adds the corresponding output port information to the front end of the valid cell introduced from the ATM service node 13, copies the input cell to the required output port using the added information, and routes it.

The ring used to connect the at least two ATM multi-duplexers 12 is in the form of a bidirectional double ring because it consists of a ring in which the cell to be transmitted is transmitted in a clockwise direction and two rings in a counterclockwise direction. In addition, two rings can be used simultaneously by an appropriate connection management method to share the load.

In order to make the most of the bandwidth of 149.76 Mbps of the two rings, it is necessary to determine which direction of the two bidirectional rings to use when establishing a connection, which is performed by the ATM service node 13. That is, the determination of the path for connection establishment is determined by the ATM service node 13, and the ATM multi-decoder 11, 12 associated with the determined path is connected to the connection control unit according to the connection establishment control command of the ATM service node 13. In step 113), connection and disconnection operations are performed.

Therefore, the control function of the multicasting channel according to the present invention is performed according to the connection setting and release operation of the connection control unit 113 in the ATM multi-definition multiplexer (11, 12), the multicasting algorithm is the ATM service node (13) A specific virtual path identifier is used as the multicasting identifier between the ATM and the ATM multiplexer (11, 12).

That is, the circuit access function 111 of the ATM multi-stage multiplexer 11 selects a corresponding cell when the ATM cell having the multicasting identifier is introduced from the ATM service node 13. The ring connection function unit 121 of the ATM multi-decoder multiplexer 12 is connected to the subscriber side line connection function unit 111 when the ATM cell having the multicasting identifier is introduced from the ring. Control the cell to be simultaneously radiated to the ring in the flow direction.

The operation of the access network having the structure as described above is as follows.

First, when a multicasting call / connection establishment request message is received from a subscriber or a multicasting connection related command is input from an operator, the call / connection control unit 131 of the ATM service node 13 is performed. At this time, the final connection path is determined according to the connection management and control algorithm for the load sharing of the bidirectional double ring, and transmits a connection control command to obtain a multicasting channel to the associated node.

Thereafter, the node receiving the connection control command records the related information in the ATM connection search table located in the circuit connection function unit 111 or the ring connection function unit 121. In this case, when a specific multicasting channel already exists, if the corresponding connection information is changed to be copied to a desired output port of the corresponding channel, a plurality of receivers may receive the same information copied from the transmitter.

If the source of the multicasting traffic is located at the subscriber side, the ATM cell flow is determined by the ATM multi-duplexer 11, the input-side circuit connection function 111, the ATM multi-reversal multiplexer 112, and the output-side circuit connection function 111. The point-to-point communication link and the circuit connection function 111 of the ATM service node 13 are transmitted to the ATM service node 13 and multicasted in the network direction or the subscriber direction.

Similarly, the ATM multi-reverse multiplexer 12 may include an input side line connection function 111, an ATM multi-reverse multiplexer 112, a ring side ring connection function 121, a clockwise or counterclockwise ring, and an ATM. After being delivered to the ATM service node 13 through the ring connection function 121 of the service node 13, it is multicasted and transmitted to each receiving side. At this time, when multicasting to another ATM multi-duplexer 12 via the ATM service node 13, it is input to the ATM service node 13 and then output converted again to be transmitted in a ring in the same direction.

On the other hand, if the source of the multicasting traffic is located on the network side, the ATM cell flow is the ATM multi-duplexer 11 is the ATM service node 13, the line connection function 111 of the ATM service node 13, point-to-point communication It is multicasted in the direction of the subscriber via the link, the input side line connection function 111, the ATM multi-reverse multiplexer 112, and the output side line connection function 111. At this time, the copy of the traffic for multicasting is in charge of the ATM multi-node multiple section 112 of the ATM service node 13 and the ATM multi-band multiplexer (11).

Similarly, the ATM multiplex multiplexer 12 includes an ATM service node 13, a ring connection function 121 of an ATM service node 13, a ring in a clockwise or counterclockwise direction, and an input side ring connection function ( 121), the ATM multi-reverse multiplexing unit 121 and the output side line connection function 111 are multicasted in the subscriber direction. At this time, the copying of the traffic for multicasting is in charge of the ATM multi-node multiple part 112 of the ATM service node 13 and the ATM multi-duplexer 12, to the ATM multi-duplexer 12 located in the ring in the same direction. In the case of multicasting, the multi-casting unit 121 is inputted to the ATM multi-duplex unit 121 through the input side ring connection function unit 121 and then output again to the ring in the same direction.

FIG. 4 is a structural diagram of the ring connection function 121 for the dual ring configuration of FIG. 1, and is described below in detail in Korean Patent Application No. "96-56551", which was previously filed on November 22, 1996, is omitted.

5A and 5B are flowcharts illustrating an embodiment of a method for establishing a multicasting channel in a load sharing bidirectional double ring according to the present invention.

The setting of the multicasting channel according to the present invention is performed on an access network composed of ATM multi-duplexers 11 and 12 and load-sharing double rings.

First, the signal / connection control unit 131 of the ATM service node 13 receives a multicasting call setup request message from a subscriber (501) or receives a multicasting connection related control command from an operator (502) to set up a multicasting channel. Understand the information.

Based on this setting information, the I / O location of the connection is determined from the call destination number and the port information to determine the input port identifier, the output port identifier, the input identifier of the input port, the connection identifier of the output port, the bandwidth of the input port, and the use of the output port. Bandwidth information is extracted (503,504). Here, the connection identifier represents a virtual path identifier / virtual channel identifier (VPI / VCI), and the bandwidth used is obtained as the maximum or average.

Thereafter, the connection path is determined from the location of the input / output port to determine a path for the multicasting channel to pass through (505).

If the channel is a path through a dual ring link, the path selection selects the path with the shortest distance and the maximum available bandwidth. Therefore, it is decided whether to use the clockwise ring or the counterclockwise ring.

First, the shortest uplink distance of the connection path is determined (506), and it is determined whether the uplink connection bandwidth is assignable (507,508).

If it is determined that the uplink connection bandwidth is assignable, the ring path of the uplink connection is determined (509), and if the uplink connection bandwidth is not assignable, the opposite ring is selected (510). It is determined whether this allocation is possible (507,508).

Thereafter, the shortest downlink distance of the connection path is determined (511), and it is determined whether the downlink connection bandwidth is assignable (512, 513).

If it is determined that the downlink connection bandwidth is assignable, the ring path of the downlink connection is determined (514), and if the downlink bandwidth is not assignable, the opposite ring is selected (515) to determine the downlink connection bandwidth of the opposite ring. It is determined whether this allocation is possible (512, 513).

Therefore, if the channel is a path through the double ring, the procedure for determining the uplink path or the downlink path is selectively processed (506 to 515), and after performing the lock control procedure (516). The multicasting channel connection establishment control command of the input / output position is transmitted to the ATM multi-duplexer 12 to establish the operation (517).

On the other hand, after the determination result, if the channel is a path passing through the point-to-point link after performing the lock control procedure (518), the multicasting channel connection establishment control command of the input and output positions to establish the connection ATM ATM multiple demultiplexer And transmits to (11) (519).

Next, a task for establishing a connection is performed in the ATM multi-duplexers 11 and 12 through which the call connection path passes, which is started by the connection establishment command of the ATM service node 13.

In order to establish a connection between the ATM multiplexer 11, 12 and the ATM service node 13, an internal connection identifier is determined, and the ATM multiplexer 11,12 is a signal / connection of the ATM service node 13. The controller 131 receives a connection setting control command of an input / output position (520), and records connection information of the corresponding multicasting channel in a search table (521). At this time, the connection identifier of the multicasting channel uses a specific virtual path identifier promised between the ATM service node 13 and the ATM multi-stage multiplexer 11 and 12 as the multicasting identifier, and the virtual channel identifier uses all connections in the system. Function to distinguish

Through the above procedure, one multicasting channel is established by transmitting configuration information of the multicasting channel to the ATM multi-duplexers 11 and 12 where the output port through which the corresponding multicasting channel passes is located.

When adding a leaf party belonging to the configured multicasting channel, the procedure for setting the corresponding leaf channel is as follows.

First, the signal / connection control unit 131 of the ATM service node 13 receives a leaf party setting request message from a subscriber (531) or receives a repeat party connection control command from an operator (532) and receives channel setting information of a corresponding leaf. Figure out.

Subsequently, the unique connection identifier, the output port identifier, and the connection port identifier (VPI / VCI) information of the output port are already obtained through the configuration information, and the party location is extracted from the information (533, 534). Accordingly, the path for the leaf channel to pass is determined by determining the connection path from the location of the extracted party (535).

If the leaf channel is a path through a dual ring link, the path selection selects the path with the shortest distance and maximum available bandwidth. Therefore, it is decided whether to use the clockwise ring or the counterclockwise ring.

First, when the connection to the party is a path through the double ring, the shortest upward distance of the connection path is determined (536), and it is determined whether the uplink connection bandwidth is assignable (537, 538).

If it is determined that the uplink connection bandwidth is assignable, the uplink connection path of the party is determined (539). If the uplink bandwidth is not assignable, the opposite ring is selected (540), and the uplink connection bandwidth of the opposite ring is determined. It is determined whether this allocation is possible (537, 538).

Next, the shortest downlink distance of the connection path is determined (541), and it is determined whether the downlink connection bandwidth is assignable (542,543).

If it is determined that the downlink connection bandwidth is assignable, the downlink path of the party is determined (544), and if the downlink bandwidth is not assignable, the downlink ring is selected (545) and the downlink bandwidth of the downlink ring is determined. It is determined whether this can be allocated (542, 543).

Thus, if the channel is a path through the double ring, the procedure for determining the uplink or downlink path of the party is optionally handled (536 to 545) and after performing the rockacque control procedure (546). In step 547, a multicasting channel connection establishment control command of an input / output location is transmitted to the ATM multi-duplexer 12 to establish a connection.

On the other hand, after the determination result, if the channel is a path through the point-to-point link after performing the lock control procedure (548), the multicasting channel connection establishment control command of the input and output positions to establish the connection ATM ATM multiple demultiplexer Transmit to 11 (549).

Next, an operation for establishing a connection is performed in the ATM multi-multiplexer (11, 12) through which the call connection path passes, which is configured information of the leaf channel to the ATM multi-multiplexer (11, 12) in which the corresponding output port is located. Is started by the transmission of.

Finally, the connection control unit 113 of the ATM multi-decoder 11, 12 receives the connection setting information from the ATM service node 13 (550), and then registers the setting information of the corresponding multicasting channel in the lookup table or already. If the set channel exists, the channel setting information of the search table is modified to copy the input cell to the output port where the leaf is located (551).

The present invention described above is capable of various substitutions, modifications, and changes without departing from the spirit of the present invention for those skilled in the art to which the present invention pertains, and the above-described embodiments and accompanying It is not limited to the drawing.

As described above, the present invention more efficiently accommodates multicasting traffic in an access network by using a load-sharing double ring that connects between an ATM endpoint subscriber having a limited bandwidth and an ATM service node, thereby efficiently using a limited ring bandwidth. It can be effective.

Claims (11)

A method of establishing a multicasting channel in an access network for connecting a geographically dispersed asynchronous delivery mode end point subscriber group to an asynchronous delivery mode service node. A first step of determining a path for the multicasting channel to pass through using the inputted configuration information and setting up one multicasting channel through the multicasting configuration information; And Second step of adding a leaf party belonging to the configured multicasting channel to set up a channel of the corresponding leaf Method for setting a multicasting channel in an access network comprising a. The method of claim 1, The first step is, A third step of determining the input / output location of the connection by determining configuration information of the multicasting channel and determining a path for the multicasting channel to pass through; A fourth step of transmitting configuration information of the multicasting channel to an asynchronous delivery mode multiplex multiplexer to establish a connection in the case of a path through a point-to-point link; A fifth step of selecting a path in which a shortest distance and a maximum available bandwidth remain in the case of a path through a dual ring link, and transmitting configuration information of a multicasting channel to the asynchronous transmission mode multiplex multiplexer; And The sixth step of receiving the configuration information of the multicasting channel and recording the connection information in the lookup table to set up one multicasting channel Method for setting a multicasting channel in an access network comprising a. The method of claim 2, The third step, A seventh step of receiving a multicasting call establishment request message from a subscriber or a multicasting connection related control command from an operator at a signal / connection controller of an asynchronous delivery mode service node; Eighth step of checking the I / O location of the connection from the called number and port information Method for setting a multicasting channel in an access network comprising a. The method of claim 2 or 3, The fourth step, A ninth step of performing a rock lock control procedure when the channel passes through the point-to-point link; And A tenth step of transmitting a multicasting channel connection establishment control command of an input / output position to the asynchronous delivery mode multiplex multiplexer to establish a connection; Method for setting a multicasting channel in an access network comprising a. The method of claim 2, The fifth step, A seventh step of determining an uppermost shortest distance of the connection path when the corresponding channel passes through the double ring link; An eighth step of determining whether uplink bandwidth is assignable; As a result of the eighth step, if the uplink bandwidth is assignable, the ring path of the uplink connection is determined. If the uplink bandwidth is not assignable, the uplink ring is selected by selecting the opposite ring to determine whether the uplink connection bandwidth of the uplink ring can be allocated. Determining a ninth step; A tenth step of determining a shortest downward direction of the connection path when the corresponding channel passes through the double ring link; An eleventh step of determining whether downlink bandwidth is assignable; As a result of the eleventh step determination, if the downlink bandwidth is assignable, the ring path of the downlink connection is determined, and if the downlink bandwidth is not assignable, the downlink ring is selected to determine whether the downlink bandwidth of the downlink ring can be allocated. Determining a twelfth step; A thirteenth step of performing a rockacry control procedure; And A fourteenth step of transmitting a multicasting channel connection establishment control command of an input / output position to the asynchronous delivery mode multiplexer to establish a connection; Method for setting a multicasting channel in an access network comprising a. The method according to claim 2 or 5, The sixth step, A fifteenth step of receiving, by the asynchronous delivery mode multiplex multiplexer, a connection setting control command of an input / output position from a signal / connection control unit of an asynchronous delivery mode service node; And A sixteenth step of recording connection information of the corresponding multicasting channel in a search table; Method for setting a multicasting channel in an access network comprising a. The method according to claim 1 or 2, The second step, Determining a path for the leaf channel to pass after determining the input / output location of the connection by identifying channel setting information of the corresponding leaf; An eighth step of transmitting configuration information of a leaf channel to the asynchronous delivery mode multiplex multiplexer to establish a connection in the case of a path through a point-to-point link; A ninth step of selecting a path in which the shortest distance and the maximum available bandwidth remain in the case of a path through a dual ring link, and transmitting configuration information of a leaf channel to the asynchronous transmission mode multiplexer; And A tenth step of receiving the configuration information of the multicasting channel, recording the connection information in the lookup table, and additionally setting the leaf channel to one multicasting channel. Method for setting a multicasting channel in an access network comprising a. The method of claim 7, wherein The seventh step, An eleventh step in which the signal / connection control unit of the asynchronous delivery mode service node receives a leaf party establishment request message from a subscriber or receives a leaf party connection control command from an operator; 12th step of confirming the input / output position of the connection from the party setting request information Method for setting a multicasting channel in an access network comprising a. The method of claim 8, The eighth step, A thirteenth step of performing a rock lock control procedure when the channel passes through a point-to-point link; And A fourteenth step of transmitting a multicasting channel connection establishment control command of an input / output position to the asynchronous delivery mode multiplex multiplexer to establish a connection; Method for setting a multicasting channel in an access network comprising a. The method of claim 7, wherein The ninth step, An eleventh step of determining an uppermost shortest distance of the connection path when the corresponding channel passes through the double ring link; A twelfth step of determining whether uplink bandwidth is assignable; As a result of the twelfth determination, if the uplink bandwidth is assignable, the ring path of the uplink connection of the party is determined. A thirteenth step of determining whether it is assignable; A fourteenth step of determining a shortest downward distance of the connection path when the corresponding channel passes through the double ring link; A fifteenth step of determining whether downlink bandwidth is assignable; As a result of the determination of the fifteenth step, if the downlink bandwidth is assignable, the ring path of the downlink connection of the party is determined. A sixteenth step of determining whether the allocation is possible; A seventeenth step of performing a rockacry control procedure; And An eighteenth step of transmitting a multicasting channel connection establishment control command of an input / output position to the asynchronous delivery mode multiplex multiplexer to establish a connection; Method for setting a multicasting channel in an access network comprising a. The method of claim 10, The tenth step is A nineteenth step of the asynchronous delivery mode multiplex multiplexer receiving a connection setting control command of an input / output position from a signal / connection control unit of an asynchronous delivery mode service node; And 20th step of modifying the configuration information of the lookup table so that connection information of the corresponding multicasting channel is recorded in the lookup table or the input cell can be copied to the output port where the leaf is located. Method for setting a multicasting channel in an access network comprising a.

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