KR100606087B1 - Queue event processing method of inverse multiplexing over atm access apparatus - Google Patents

Abstract

The present invention relates to a method of processing a queue event in an IMA access device, comprising: analyzing contents of an ICP cell received from a counterpart through a queue, and analyzing the ICP cell; If there is a change in the contents of the ICP (ICP) group, the process of applying the partner state and the partner state of the corresponding group for all links corresponding to the event variable, respectively, and to send the status machine message corresponding to the event variable to the queue again And executing the corresponding state machines using the state of each link and group and the event number in the queue message according to the state machine message delivery.

Inverse Multiplexing over ATM (ICA), IMA Cell Protocol (ICP) Cells

Description

QUEUE EVENT PROCESSING METHOD OF INVERSE MULTIPLEXING OVER ATM ACCESS APPARATUS}             

1 is a configuration diagram for explaining the IMA function,

2 is a configuration diagram illustrating an ICP cell flow;

3 is a message queue processing flowchart for state management of groups and links according to the prior art;

4 is a message queue processing flow diagram of a group and a link according to an embodiment of the present invention.

The present invention relates to an asynchronous transfer mode (hereinafter referred to as "ATM") switching system, in particular Asynchronous Transfer Mode (Asynchronous Transfer Mode) Inverse Multiplexing (IMUX, or Inverse Multiplexing over ATM: IMA, hereinafter) Referred to as "IMA".

The IMA specification aims to allow ATM traffic to travel over several relatively slow lines, rather than over a single expensive line. Therefore, IMA is suitable when there is too much data to use T1 (1.44Mbps) transmission line but little data to use T3 (44.736Mbps) transmission line.

The operation principle of the IMA will be described below. The physical lines currently used as interfaces in the ATM network architecture include T1 (1.544 Mbps), E1 (2.048 Mbps), DS3 (45 Mbps), and STM1 (155 Mbps). Although DS3 and STM1 have a large transmission bandwidth, the maintenance cost is high in actual operation, and T1 and E1 are relatively small but are actually used a lot. The starting point of the IMA's function is to designate several lines into one group (IMA group) through the existing low-speed lines that are already installed to efficiently transmit data.

1 is a configuration diagram for explaining the IMA function. Referring to FIG. 1, a plurality of physical links 6 (for example, physical link # 0, consisting of a low speed line (T1 / E1 line)) between an originating IMA access device 2 and a destination IMA access device 4 are provided. 1,2) are connected. The originating IMA access device 2 distributes one ATM cell stream received from the ATM layer into a plurality of streams and then through the corresponding plurality of physical links 6 (eg, physical links # 0, 1, 2). It transmits to the called party's IMA access device 4. The destination IMA access device 4 combines the plurality of streams received through the physical layers 6 into one ATM cell stream and transmits the same to the ATM layer. The ATM cell stream distribution in the source IMA access device 2 and the ATM cell stream combination in the destination IMA access device 4 are usually made in a round robin sequence.

In order to enable the transmission between the IMA access devices 2 and 4 as described above, specific cells called ICP Cells (ICP cells) (hereinafter referred to as "ICP cells") are transmitted and received on each of the plurality of physical links 6. . The ICP cell provides the IMA access devices 2 and 4 with information relating to synchronization and link status between links established as one IMA group and one IMA group. Each of the IMA access devices 2 and 4 may be divided into at least one IMA group, and one IMA group includes ICP cells transmitted on a plurality of physical links 6, respectively, as shown in FIG. have.

2 is a diagram showing that an ICP cell is transmitted on each link designated as an actual IMA group. Referring to FIG. 2, an IMA group is divided into IMA frames and is composed of a plurality of IMA frames. Each IMA frame includes one ICP cell. Each of the IMA access devices 2 and 4 can read the contents of the ICP cell to know the changed information on the other side, and can also notify the other side of its own changed contents. Through these ICP cells, the IMA group of the IMA access devices 2 and 4 can know the status of the other party's link and the group, and determine the availability of the group by exchanging their status. In FIG. 2, the symbol "ICPi" in the cells configured in each of the IMA frames means the ICP cell in the i-th frame (i is the IMA frame number), and the symbol "F" denotes meaningless data as a filler cell. "ATM" means an ATM cell.

As shown in FIG. 2, a logical link formed between the IMA access devices 2 and 4 by the ICP cells is shown as an IMA virtual link in FIG.

As described with reference to Figs. 1 and 2, in implementing the IMA function, a state machine for managing the IMA group state and the IMA link state exists in each of the IMA access devices 2 and 4, There is a need for a routine to process the contents of the received ICP cell. The state machine refers to a series of tasks that change the state of each link and group according to the contents of the ICP cell and the state change of the user side. Among the state machines, the group state machine checks the state of its IMA access device IMA group and performs a function according to the change of the opponent IMA group state. Among the state machines, a link state machine checks the states of links in its IMA access device and performs a function according to the link state change of the other party.

3 is a message queue processing flowchart performed by the IMA process of each of the IMA access devices 2 and 4 for state management of groups and links according to the prior art.

Referring to FIG. 3, the IMA process of the IMA access devices 2 and 4 stores the contents of the ICP cell received from the counterpart through the queue in the buffer (steps 100 and 102). Then, by checking the status of each link (receive link and transmit link) corresponding to the corresponding ICP cell group (step 104 and 108), the existing content and the changed link is found. It then calls the link state machine process for the changed links, which take action corresponding to the changes (steps 106 and 110).

When the IMA process completes the links, it checks the status of the group (step 112) and also invokes the group state machine process for the changes (step 114). In addition, other changes are checked (step 116) and the corresponding other processes are called and executed (step 118).

After all execution, the IMA process transitions to the event wait state and waits for a new queue message.

In the queue operation, all processors should be able to guarantee all events that can occur later by minimizing the routines that operate on the events. The prior art as described above has a lot of processing delays checked for the arrival of one ICP cell. Bringing in causes a loss in processing the queue.

Accordingly, an object of the present invention is to provide a method of maximizing queue use by minimizing a queue event processing routine in an IMA access device performing an IMA function.

According to the above object, the present invention, in the queue event processing method in the IMA (IMA) access device, the process of analyzing the contents of the ICP (ICP) cell received from the counterpart through the queue, and the analysis If there is a change in the contents of the ICP cell, the partner state for all links corresponding to the ICP group and the partner state of the group are applied as event variables, respectively, and the queues correspond to the event variables. A machine message is delivered, and each state machine is executed by using a state number of each link and a group and an event number in a queue message according to the state machine message delivery.

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

In order to simplify the processing routine when a queue event occurs in the IMA access device 2 or 4 performing the IMA function, the processing sequence as shown in FIG. 4 is applied. 4 is a flowchart illustrating message queue processing of groups and links according to an embodiment of the present invention.

Referring to FIG. 4, the IMA process of the IMA access devices 2 and 4 analyzes the contents of the ICP cell received from the counterpart through the queue (steps 200 and 202). As a result of the analysis, when the changed ICP cell is received (step 204), the IMA process applies the partner state for all links corresponding to the group of the ICP as an event variable and again queues IMA_RX_LSM (IMA_RX_Link State Machine), and IMA_TX_LSM ( IMA_TX_Link State Machine) message is sent (step 206).

Thereafter, the relative state of the corresponding group is applied to the event variable, and an IMA_TX_Group State Machine (IMA_GSM) message is transmitted to the queue (step 208).

The queue will again accept events and, in the case of IMA_RX_LSM, IMA_TX_LSM, and IMA_GSM, receive the link state machine table (RxLSMTable), send link state table (TxLSMTable), and group link state machine table with the status of each link, group, and event number in the queue message. Call each function corresponding to (GSMTable). Each of the called state machines is executed (steps 210, 212, 214, and 216).

 As described above, the present invention makes the process easy to cope with each situation by simplifying the routine to handle when a queue event occurs as much as possible, and by having a processing routine for each state as a function and having a table. After that, when the state is added, it provides a function to efficiently handle the response when adding the event. The state machine implementation using the queue of the present invention provides a function that can efficiently program coding by defining states and events in various other functions.

Claims (3)

In the queue event processing method in the IMA (IMA) access device, Analyzing the contents of the IMA Cell Protocol (ICP) cell received from the other party through the queue; If there is a change in the contents of the analyzed ICP cell, the relative state of all links corresponding to the ICP group and the relative state of the corresponding group are respectively applied as event variables, and then queued to the event variable. Delivering a corresponding state machine message; And executing each corresponding state machine using the state of each link and group and the event number in the queue message in response to the state machine message delivery. 2. The method of claim 1, wherein the group consists of at least two links. 3. The method of claim 2, wherein said at least two links comprise a receive link and a transmit link.

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