KR100204030B1 - Releasing method of virtual connection identifier in atm switching system - Google Patents

Abstract

1. Technical field to which the invention described in the claims belongs

Asynchronous forwarding mode A method of releasing a connection identifier that allows the exchange system to release for all range of connection identifiers

2. Technical Challenges to be Solved by the Invention

In the ATM switching system, the available range is enormous, and it is almost impossible to manage the use of these values by displaying each subscriber link.

3. The point of the solution of the invention

When the virtual path connection is released, the virtual path identifier (VPI) state is changed by calculating the index value of the virtual path identifier (VPI) table and directly accessed. When the virtual channel connection is released, (VPI) of the virtual path identifier (VPI) to which the virtual channel identifier (VCI) belongs after deleting the virtual channel identifier (VCI) by accessing the virtual path identifier I want to provide.

4. Important Uses of the Invention

It is used to release the connection identifier when calling and disconnecting when the range of the connection identifier recommended by the International Telecommunication Union (ITU-T) is used up.

Description

How to Disable a Connection Identifier in an Asynchronous Transfer Mode (ATM) Switching System

FIG. 1 is a schematic configuration diagram of an ATM switching system to which the present invention is applied; FIG.

FIG. 2 is a block diagram of a function block for clearing a connection identifier in an ATM switching system. FIG.

3a through 3c are flowcharts according to the present invention for releasing a virtual path identifier / virtual channel identifier (VPI / VCI), which is a connected identifier for virtual channel disconnect in an ATM switching system.

4 is a flow diagram according to the present invention for releasing a virtual path identifier (VPI), which is a connection identifier for a virtual path disconnect in an ATM switching system.

DESCRIPTION OF THE REFERENCE NUMERALS

1: ATM Local Switching Subsystem (ALS)

2: ATM central exchange subsystem (ACS)

3: Subscriber matching module (SIM) 4: Connection switching control module (ASCM)

5: Operation Maintenance Control Module (OMCM)

The present invention relates to an Asynchronous Transfer Mode (ATM)

The present invention relates to a method for releasing a connection identifier in a switching system in which all ranges of connection identifiers can be released.

A virtual path identifier (VPI / VCI) is used as an identifier for distinguishing a connection between a subscriber and a network in an ATM switching system. In the ATM switching system, the subscriber matching type is DS1E (Didital Signal level 1 European) supporting 2.048 Mbps, Digital Signal level 3 (DS3) supporting 44.736 Mbps, Synchronous Transport Module 1 (STMI) supporting 155 Mbps, 622 Mbps (STM4 (Synchronous Transport Module 4) class). One STM class 1 subscriber link is matched in the subscriber matching module according to the type of subscriber link that is connected in the subscriber interface module (SIM), and 72 DS class 3 subscriber links and 3 DS1E class subscriber links are matched .

In the ITU-T Recommendation Q.2931, which recommends that subscribers and manganese be matched to realize broadband services, the virtual path identifier (VPI) for each subscriber interface (interface) ranges from 0 to 255 , The virtual channel identifier (VCI) in the virtual path is specified to use a value from 32 to 65535. [

In a conventional narrowband integrated information network (N-ISDN) exchange, the number of channels limited within the physical link of the subscriber and the network is allowed. For example, the 2B + D interface has two channels for transmitting user data, so that the subscriber data can be easily distinguished by distinguishing only two channels.

Therefore, in the interface between the subscriber and the manganese, the channel number cancellation was merely changed from in use to unused.

However, since the bandwidth provided by one physical link can be more than 155Mbps in the registration of the subscriber and the network in the broadband integrated information communication network (B-ISDN), information on a plurality of connections is multiplexed and transmitted. At this time, a connection identifier for distinguishing the user information is used. The use area is a wide value having a virtual path identifier (VPI) of 8 bits and a virtual channel identifier (VCI) of 16 bits.

Therefore, there is a problem that the available range of the ATM switching system is so large that it is almost impossible to display and manage the use of these values for each subscriber link.

In order to solve the above problems, it is an object of the present invention to provide a system and method for enabling release of a CID when a call and a connection are released even when the range of the CID recommended by the International Telecommunication Union (ITU-T) And a virtual path identifier (VPI) state is changed by directly accessing an index value of a virtual path identifier (VPI) table when the virtual path connection is released.

It is another object of the present invention to solve the above-mentioned problems, and it is an object of the present invention to provide a system and method for enabling a connection identifier to be released when a call and a connection are released even when the range of the connection identifier recommended by the International Telecommunication Union (ITU- The virtual channel identifier (VCI) table is accessed to delete the virtual channel identifier (VCI), and the connection status in the virtual path identifier (VPI) to which the virtual channel identifier (VCI) belongs is analyzed And to determine whether to release the virtual path identifier (VPI).

That is, when only the virtual path identifier (VPI) is allocated through the present invention, the virtual path is released only when the connection is released. When the virtual channel connection is canceled by allocating the virtual channel identifier (VPI / VCI) Releases the virtual channel identifier (VPI / VCI). It may be used in establishing a virtual channel connection after the virtual path identifier (VPI) allocated for the virtual path connection is released.

According to an aspect of the present invention, there is provided a connection identifier releasing method applied to an asynchronous transfer mode (ATM) switching system. The connection identifier releasing method includes a first step of calculating an index value for accessing a virtual path identifier table ; A second step of checking the use state of the virtual path identifier being used by the connection to be released and the use state of the virtual channel identifier and deleting the connection identifier (VPI / VCI) to be released from the virtual channel identifier table; And a third step of checking whether there is a virtual channel identifier in use in the virtual path identifier, and releasing the virtual path identifier designated when the virtual channel identifier in use does not exist.

According to another aspect of the present invention, there is provided a connection identifier releasing method applied to an asynchronous transfer mode (ATM) switching system, the method comprising: receiving a virtual path identifier (VPI) A first step of calculating an index value for accessing a table; A second step of checking the use state of the virtual path identifier (VPI) if the calculated index value is normal and changing the use state of the virtual path identifier (VPI) to the unused state after decrementing the number of connections by 1 if the index value is in use; And a third step of decreasing the number of virtual path identifiers (VPI) used by 1 and notifying completion of release of the virtual channel identifier.

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

FIG. 1 is a schematic diagram of an ATM switching system to which the present invention is applied. In FIG. 1, reference numeral 1 denotes an ATM Local Switching Subsystem (ALS), 2 denotes an ATM Central Switching Subsystem (ACS) 3 denotes a Subscriber Interface Module (SIM), 4 denotes an Access Switching Control Module (ASCM), and 5 denotes an Operation Maintenance Control Module.

The ATM switching system is distributed in units of independent ATM Local Switching Subsystem (ALS) (1) and interconnected by an ATM Central Switching Subsystem (ACS) (2). do.

The ATM local exchange subsystem (ALS) 1 includes a subscriber interface module (SIM) 3 for performing cell transmission and reception between a subscriber and a network, an access switching control module (ASCM) 3 for controlling subscriber calls and connections, The ATM Switching Subsystem (ACS) 2 is provided with an Operation Maintenance Control Module (OMCM) 5 for performing operator coordination and in-system operation and maintenance functions, (4).

FIG. 2 is a functional block diagram for releasing the connection identifier in the ATM switching system.

A software function block for clearing the connection identifier is built in the Call Connection Control Processor (CCCP) in the ATM Local Switching Subsystem (ALS)

The Semi-permanent PtP Virtual Connection Control Function (SPVCF) block 6 controls the point-to-point dedicated line service requested from the management plane function.

The Semi-permanent PtMP Virtual Connection Control Function (SMVCF) block 7 controls the point-to-multipoint dedicated line service requested from the management plane function.

A User Protocol Control Function (UPCF) block 8 controls a subscriber call according to transmission / reception of a Q.2931 message with a subscriber terminal.

The ULRHF (UNI Link Resource Handling Function) block 9 is a block on which the present invention is performed and performs a function of releasing a connection identifier required for connection release in the SPVCF 6, SMVCF 7, and UPCF 8 blocks , And performs a call processing library function.

The SIM 3 receives the connection release information from the SPVCF 6, the SMVCF 7 and the UPCF 8 block and performs transmission and reception processing on the subscriber information cell.

FIG. 3a is an overall flowchart according to the present invention for releasing a virtual path identifier / virtual channel identifier (VPI / VCI) which is a connection identifier for disconnecting a virtual channel in an ATM switching system.

(31) analyzes whether the subscriber matching module number requested to release the connection identifier (VPI / VCI) and the virtual path identifier (VPI) requested to be released are normal (32) when receiving the connection identifier release request from the call and connection release function If it is determined to be abnormal, the call and connection processing function is notified that the connection identifier (VPI / VCI) can not be released, and the function is terminated (43). If it is determined to be normal, the index value for accessing the virtual path identifier (VPI) table is calculated 33).

Thereafter, the calculated index value is analyzed (34). If it is determined to be an error, it is notified that it can not be released to the call and connection processing function, and the function is terminated (43). If it is not an index error, the connection to be released checks the use status of the virtual path identifier (VPI) in use (35). If it is not in use, it notifies the call and connection control function of completion of the connection identifier release and terminates (42). If the virtual path identifier is in use, the use status of the virtual channel identifier (VCI) is checked. (36) If it is determined that the virtual path identifier is not in use, the completion of the release of the connection identifier is notified to the call and connection control function. If the virtual channel identifier is in use, the virtual path identifier / virtual channel identifier (VPI / VCI) to be released in the virtual channel identifier (VCI) table is deleted (37).

After the number of connections in the subscriber matching module is decreased by one (38), the number of connections in the virtual path identifier (VPI) is checked (39). If the number of connections in the virtual path identifier (VPI) is greater than 0, completion of connection identifier release is notified to the call and connection control function (VPI) state is changed to unused (40), the number of virtual path identifiers (VPI) is decremented by 1 (41), and the connection identifier (VPI / VCI) And notifies the call and connection control function and terminates the function (42).

FIG. 3b is a detailed flowchart of a process 37 for deleting a designated connection identifier (VPI / VCI) from the virtual channel identifier (VCI) table.

First, a subscriber matching module number to which a connection identifier (VPI / VCI) to be deleted belongs is accessed as an index value and a virtual channel identifier (VCI) table is accessed to obtain an array index value of a virtual channel identifier (VCI) table corresponding to the subscriber matching module number (44) If the stored connection identifier (VPI / VCI) matches the requested connection identifier (VPI / VCI) If the number of accesses to the virtual channel identifier (VCI) table is equal to or greater than the number of accesses to the virtual channel identifier (VCI) table after the connection identifier (VPI / VCI) value is deleted from the virtual channel identifier (47) after informing that the selected virtual channel identifier (VCI) value is deleted from the table after the memory is packed from the index value indicating the memory in which the deleted virtual channel identifier (VCI) is stored 48).

3C shows a case where the connection identifier (VPI / VCI) being used is stored even after the memory location in the virtual channel identifier (VCI) table in which the connection identifier (VPI / VCI) And storing the empty memory area as -1 after moving the memory location without allowing the virtual channel identifier (VCI) table to be referenced, the number of references in the virtual channel identifier (VCI) table can be reduced.

First, a connection identifier (VPI / VCI) value stored in a memory area indicated by a virtual channel identifier (VCI) table index requested to be packed is read and analyzed to determine whether the content is stored as -1 (49) 1, it is notified that the movement of the memory storage location of the virtual channel identifier (VCI) table is completed, and the function is terminated (54). In this case, when it is stored as -1, it means that the memory is already packed after the memory in which the deleted connection identifier (VPI / VCI) is stored.

On the other hand, if it is not stored as -1, the storage location of the virtual channel identifier (VCI) table is moved by one tuple (50), and then it is determined whether the index value is the maximum allowed number of connections in the corresponding subscriber matching module 51) or (49) from the step (49) of determining (52) whether the connection identifier value is -1 with the index value of the virtual channel identifier (VCI) table increased by one.

(VPI / VCI) table stored in the virtual channel identifier (VCI) table is moved according to the repetition, and then the index value for accessing the virtual channel identifier (VCI) table in the state where the packing is completed VCIIndex: stores the contents of the table indicated by the last identifier of the connection identifier storage location after moving the storage identifier to -1, (53) notifies that the movement of the memory storage location of the virtual channel identifier (VCI) table is completed, (54).

4 is a flowchart according to the present invention for releasing a virtual path identifier (VPI), which is a connection identifier for a virtual path disconnect in an ATM switching system.

(55) analyzes whether the subscriber matching module number requested to release the virtual path identifier and the virtual path identifier (VPI) requested to be released are normal (56) upon reception of the virtual path identifier (VPI) If it is determined to be abnormal, the call and connection processing function is notified that the virtual path identifier can not be released, and the function is terminated. (64) If it is normal, the index value for accessing the table storing the virtual path identifier (VPI) )

If the range of the calculated index value is normal 58, if it is abnormal, the virtual path identifier release failure is notified to the call and connection processing function and the function is terminated. If it is normal, the virtual path identifier (VPI) (59) If it is determined that the virtual channel identifier is unused, the virtual channel identifier is notified of completion of the release and the function is terminated (63). If it is determined that the virtual channel identifier is in use, the number of connections is decreased by 1 (60).

After changing the use state of the virtual path identifier (VPI) to unused (61), the use number of the virtual path identifier (VPI) is decremented by 1 (62), the virtual channel identifier release completion is notified and the function is terminated (63).

The above-described feature of the present invention enables the release of the connection identifier upon calling and disconnecting even when all the range of the connection identifier recommended by the International Telecommunication Union (ITU-T) is used, T), there is no restriction on the range of the connection identifier, and it is possible to determine whether the virtual path identifier is in use by selecting the connection identifier management method as an index table, thereby minimizing the connection identifier release time There is an effect that can be.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. The present invention is not limited to the drawings.

Claims (8)

A connection identifier releasing method applied to an asynchronous transfer mode (ATM) switching system, the method comprising: a first step of calculating an index value for accessing a virtual path identifier table upon receiving a connection identifier release request; A second step of checking the use state of the virtual path identifier being used by the connection to be released and the use state of the virtual channel identifier and deleting the connection identifier (VPI / VCI) to be released from the virtual channel identifier table; And a third step of checking whether there is a virtual channel identifier in use in the virtual path identifier, and releasing the virtual path identifier specified when the virtual channel identifier in use does not exist, in the asynchronous delivery mode switching system . The method of claim 1, wherein the first step comprises: analyzing whether the subscriber matching module number requested to cancel the connection identifier and the released virtual path identifier are normal when receiving the connection identifier release request; A fifth step of analyzing a calculated index value after calculating an index value for accessing a virtual path identifier table if it is determined to be normal as a result of the analysis in the fourth step; And a sixth step of informing that the analysis result of the fourth step is abnormal or the failure of the connection identifier release if the analysis result of the fifth step is found to be an error. 3. The method of claim 1 or 2, wherein the second step comprises: checking a use state of the virtual path identifier being used by the connection to be released, and checking the use state of the virtual channel identifier if the virtual path identifier is in use; An eighth step of deleting a connection identifier (VPI / VCI) to be released from the virtual channel identifier table if the virtual channel identifier is in use in the seventh step; And, if the virtual path identifier or the virtual channel identifier is not in use in the seventh step, notifying completion of the connection identifier release in the asynchronous transfer mode switching system. 4. The method of claim 3, wherein the third step comprises: decreasing the number of connections in the subscriber identity module by one and checking whether the number of connections in the virtual path identifier is greater than zero; An eleventh step of decreasing the number of virtual path identifiers used by 1 after changing the virtual path identifier state to unused and notifying completion of clearing a connection identifier (VPI / VCI) if the virtual path identifier state is less than 0 in step 10; And, if it is greater than 0 in step 10, notifying completion of the connection identifier release immediately. The method as claimed in claim 1, wherein, in the step of deleting the connection identifier (VPI / VCI) in the second step, a virtual channel identifier table is accessed using an index value of a subscriber matching module number to which a connection identifier (VPI / VCI) A fourth step of comparing whether the connection identifier (VPI / VCI) stored in the array index value of the virtual channel identifier table matching the subscriber matching module number matches the connection identifier (VPI / VCI) requested to be deleted; If it is determined that the two connection identifiers do not coincide with each other, repeating the fourth step with an index value of the virtual channel identifier table incremented by one; (VCI) table is deleted from the virtual channel identifier (VCI) table if the two identifiers match as a result of the comparison in the fourth step, and then the virtual channel identifier (VCI) table is deleted And a sixth step of notifying that the selected virtual channel identifier (VCI) value has been deleted from the table after storing the memory from an index value indicating a memory in which the virtual channel identifier (VCI) A method for releasing a connection identifier in a forwarding mode switching system. The method as claimed in claim 5, wherein, in the step of deleting the connection identifier (VPI / VCI) value in the virtual channel identifier (VCI) table in the sixth step, the virtual channel identifier (VCI) table index, (VPI / VCI) value stored in the memory area to analyze whether the valid information is stored; If the valid information is not stored, notifying that the movement of the memory storage location of the virtual channel identifier (VCI) table is completed; If valid information is stored, the storage location of the virtual channel identifier (VCI) table is moved by one tuple and stored, and then it is checked whether the index value is the maximum allowed number of connections in the corresponding subscriber matching module. Otherwise, Repeating the steps from the seventh step with an index value of an identifier (VCI) table; If the index value is equal to the maximum allowed number of connections in the subscriber matching module according to the iterative performance, the contents of the table indicated by the index value for accessing the virtual channel identifier (VCI) table is changed to the state (-1) And notifying that the movement of the memory storage location of the virtual channel identifier (VCI) table is completed after storing the connection identifier in the asynchronous transfer mode switching system. A connection identifier releasing method applied to an asynchronous transfer mode (ATM) switching system, the connection identifier releasing method comprising the steps of: calculating an index value for accessing a table in which a virtual path identifier (VPI) Stage 1; A second step of checking the use state of the virtual path identifier (VPI) if the calculated index value is normal and changing the use state of the virtual path identifier (VPI) to the unused state after decrementing the number of connections by 1 if the index value is in use; And a third step of decreasing the number of virtual path identifiers (VPI) usage by 1 and notifying completion of release of the virtual channel identifier. The method of claim 7, wherein upon receiving the virtual path identifier (VPI) release request, the first step analyzes whether the subscriber matching module number requested to release the virtual path identifier and the virtual path identifier (VPI) Step 4; A fifth step of analyzing whether the range of the calculated index value is normal after calculating an index value for accessing a table in which the virtual path identifier (VPI) use state is stored if the analysis result of the fourth step is normal; And a sixth step of informing the virtual path identifier release failure when the analysis result of the fourth step is abnormal or the analysis result of the fifth step is abnormal.