KR20010008718A - Permanent virtual connection establishment apparatus and method for base station controller in mobile communication system - Google Patents

Abstract

PURPOSE: A method for setting up a permanent virtual connection(PVC) of an asynchronous transfer mode(ATM) transmission section in a base station controller(BSC) of a mobile communication system is provided to make the BSC set up the PVC, so as to improve the efficiency. CONSTITUTION: A base station controller(BSC) analyzes a permanent virtual connection(PVC) setup command inputted by an operator. The BSC confirms whether a virtual path/virtual channel number for being set up is capable of being received. The BSC receives a new connection identifier, and sets up a driver for transceiving asynchronous transfer mode(ATM) cells and a parameter for setting up a switch-structured route path. The BSC initializes an ATM adaptation layer(AAL) driver to disassemble/assemble upper data as the ATM cells, and sets up values necessary for searching/removing factors influencing service quality of other preset connections in a usage parameter control driver. The BSC requests a route path setup to a cell route server. If the cell route server sets up a valid route path, a destination port value of a multicast group table is set up. The BSC informs a task requesting a data transmission of a virtual path connection setup completion, to start a data transceiving process.

Description

PERMANENT VIRTUAL CONNECTION ESTABLISHMENT APPARATUS AND METHOD FOR BASE STATION CONTROLLER IN MOBILE COMMUNICATION SYSTEM}

The present invention refers to a base station controller (hereinafter referred to as BSC) located between a base station (hereinafter referred to as BTS) and a mobile switching center (hereinafter referred to as MSC) in a mobile communication system. In particular, the present invention relates to an Asynchronous Transfer Mode (hereinafter referred to as ATM) and a permanent virtual connection (PVC) of a transmission section.

The BSC performs functions such as location registration service access, call and real time traffic processing, handoff processing, switch matching, and the like of the mobile terminal.

Since the data rate of PCS or cellular system is only 9.6-14.4Kbps, it is impossible to provide high-speed data service or multimedia service including video. Therefore, PCS and cellular systems have many limitations. This led to the emergence of the concept of next-generation mobile communications services that are distinct from the PCS systems currently being deployed. By effectively utilizing the advantages of IMT-2000 ATM technology that transmits next generation mobile network service based on ATM technology, it provides flexibility in bandwidth allocation and traffic selection according to service type for various types of next generation mobile network service. Multiplexed to multimedia traffic efficiently.

In the IMT-2000 system, the most noticeable difference from the existing services is high-speed packet data service and multimedia service. In particular, high-speed packet data service is essential for a large number of users to receive data services represented by services such as wireless Internet, file transfer, and e-mail at high speed using limited wireless channels. The use of ATM in the IMT-2000 BSC system enables the transmission of multimedia information such as data and video, as well as voice-oriented services supported by existing cellular and mobile networks with high-speed data transmission and high bandwidth support. By using ATM technology in BSC system, it is possible to establish ATM connection with various kinds of quality of service (QOS) in bandwidth allocation and traffic selection according to service type. The basic structure of BSC system is ATM switch. This allows for fast inter-cell switching.

Accordingly, an object of the present invention is to provide an apparatus and method for establishing asynchronous transmission mode persistent virtual access in a base station controller of a mobile communication system.

1 is a diagram showing the configuration of a third generation CDMA system applicable to IMT-2000;

2 is a diagram illustrating an internal configuration of a BSC system in an IMT-2000 system;

3 is a diagram illustrating the structure of an ATM connection portion of an ATM subscriber board;

4 shows the PVC configuration needed to turn on and off ATM PVC.

5 is a diagram illustrating a configuration of a connection table.

6 is a flow chart showing a point-to-point PVC setup procedure

7 is a flow chart showing a point-to-multi-PVC setup procedure

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals have the same reference numerals as much as possible even if displayed on different drawings. In addition, many specific details appear in the following description, which is provided to help a more general understanding of the present invention, and the present invention may be practiced without these specific details. Will be self-evident. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a diagram showing the configuration of a third generation CDMA system applicable to IMT-2000.

The BSC 410 is responsible for call processing and resource management between the MSC 100 and the BTS 500. Although not shown, the BSC 410 includes a vocoder, a call control module, a handoff / selection processing module, and an SS.7 interface. In addition, the BSC 410 is used to connect the BTS 500 and another BSC to each other through its ATM switch 405. In addition, the BSC 410 is used to interconnect various processors in the BSC system.

The base station manager (BSM) 300 is a global ATM network (GAN) 200, and BSCs, BTSs, and a network management station that manages a network directly connected to the GAN 200 (hereinafter, referred to as a NMS). .)to be.

The BTS 500 connects a mobile terminal through a CDMA air interface. Although not shown, the BTS 500 is composed of an antenna, RF, IF, GPS, channel card elements, and the like.

The GAN 200 is composed of upper ATM switches that connect the data transfers between the 12 BSCs, and provides a soft-handoff path between the BSCs and a management path of the BSMs.

2 is a diagram illustrating an internal configuration of a BSC system in an IMT-2000 system.

Here, blocks such as ATP, BMP, and TCB act as subscriber boards when the BSC is an ATM switch.

3 shows the structure of an ATM connection portion of an ATM subscriber board.

The physical media (PM) sublayer depends on the amount of input / output data required for each processor element. There are 2Mbps between the B1 and the BCS's E1ATM (Section ⓓ), and between GAN and STM1ATM (Section ⓑ) and GAN and BSM (ⓐ section). Functions related to, for example, to perform functions related to optical fibers, light emitting devices, optical connectors.

Transmission Convergence (TC) forms a transmission frame and provides a function of inserting or extracting cells, and is implemented in the E1-ATM board and the STM1ATM board of FIG. 2.

ATM and ATM Adaptation Layer (AAL) layer functions must be implemented on all subscriber boards and BTSs. The ATM layer has processing functions for all sections of the ATM cell header except HEC, and ATM connections related to VPI / VCI. Perform control and other processing functions related to PT and CLP.

The AAL layer is the middle layer between the ATM layer and the senior user service layer. The main function is to bridge the gap between the services provided by the ATM layer and the services required by the user. To this end, the AAL matches user service information with ATM cell format, and handles transmission errors, handles lost or inserted cells, and handles error cells. The AAL layer forms a user segment of an ATM cell by cutting a protocol data unit and a CS (Convergence Sublayer) portion that makes service information of a higher layer into a protocol data unit or vice versa. It can be divided into segmentation and reassembly (SAR).

Traffic generated inside the BSC system is transmitted using an ATM IPC channel. Referring to FIG. 2, a virtual channel is established between the BTS and the ESC of the BSC (section ⓓ) and between the GAN and the STM1ATM (section ⓑ). Only user traffic and control information can be transmitted.

The virtual channel is classified into a switched virtual channel (SVC) and a permanent virtual channel (PVC). Since the SVC can set or release various types of connections according to the user's request, the SVC can use the transmission band efficiently, but the channel setting time of the two nodes takes a little time. The PVC has the advantage of reducing the connection connection, disconnection setting time because it is used by setting the channel once in a long time and permanently according to the user's request, but it is difficult to manage the channel smoothly because the transmission band is fixed. Therefore, in order to support soft handoff, normal user data transmission is possible only when the channel setup time is made within 10-15msec.However, between BTS and BSC's E1ATM (section ⓓ) and between GAN and STM1ATM (ⓑ section) ), SVC processing can exceed the setup time and can cause many problems.

Therefore, in the transmission section using ATM, PVC is set as an IPC channel to transmit user traffic and control information, and the internal IPC is also used in the ⓒ section of FIG. 2 of the ATM switch fabric and each I / O board. After the subscriber board initializes ATM and AAL related functions during system operation, it determines the PVC between the boards according to the already determined IPC channel procedure.

4 is a diagram showing a PVC configuration required to turn on and off ATM PVC.

The IPC connection configuration function informs the PVC manager of the following initial information to configure the IPC channel between boards when booting the boards that make up the BSC system.

PVC form: point to point or point to multipoint

Source user information: switch port number, VPI / VCI number

Destination user information: switch port number, VPI / VCI number

Source to destination traffic parameters

: Traffic setting request bandwidth, QOS type information

Destination-to-source traffic parameters

: Traffic setting request bandwidth, QOS type information

Tag value for the access path in the switch fabric

-Multicast group value, input VP / VC value, and VP / VC list added to multicast group when multicasting is set.

The routing table driver has a table that contains information about the routing of ATM cells in the ATM switch fabric. The connection processor includes input / output boards (BMP, ATP, After setting the path between MMX, etc., the following table is notified to the routing table driver.

-Deal with priority by class of service.

Tag value for the access path within the switch fabric

-Cell MUX tag value corresponding to the given destination port

-Input and output VP / VC value for each VP / VC

-Delete VP / VC when disconnecting

-Multicast group value, input VP / VC value, and VP / VC added to multicast group when setting multicasting

-Multicast disconnect

The user interface unit analyzes the PVC-related commands entered by the operator to form an IPC message and informs the PVC manager. It is mounted on each board that sets up PVC connection as a block that performs operator input command processing to send IPC message and output message and system output message for input command to operator console. . Inform the ATM driver and management part about PVC-related commands as follows:

-PVC connection setting status by board

-Set up / release PVC PTP connection

-Add / Delete PVC PTMP Connection

-PVC connection test

-PVC connection information

PVC access priority

The AAL5 / UPC (Usage Parameter Control) driver receives and sets traffic parameters for each channel through the connection processing unit when the PVC manager sets up the system IPC connection or sets up / releases the connection through the user interface. .

The PVC Manager performs a series of processes related to creating, managing and releasing PVC channels. The PVC initialization unit is created by the root task. It creates PVC-related tasks such as PVC manager and access processing unit and initializes PVC-related variables. Also, the IPC connection configuration process of each board of the BSC is performed using the information of the IPC connection configuration unit.

The connection processing section is responsible for setting / release of the PVC channel at the VP / VC connection level. When the PVC manager establishes a PVC connection, the PVC manager instructs the connection processor to allocate a global connection identifier to the connection table and to have a connection establishment process according to the traffic variable. The connection processing unit manages the connection for each connection ID of the connection table. In the case of PTMP connection, the connection processing unit adds and deletes the multicast group ID. Also, the connection processing unit sends the connection-related setting values from the AAL5 and UPC drivers, and the connection with the cell route server unit. It finds the cell route path and informs the RT driver. 5 is a diagram illustrating a configuration of the connection table.

Referring back to FIG. 4, the resource management unit manages a state of the PVC connection connecting the boards and the boards between the calling party and the called party of the transmission section of the BSC. For each connection, the current occupied band and effective band management are performed for each channel element. In the process of requesting mobile call setup, the BSC processes a series of processes to decide whether to accept or reject an access request by referring to the resource management table managed by the resource management unit for each VP / VC. To make it possible. A cell route server is a block that determines a route in a cell switch fabric for each connection according to a routing request of a switch I / O board. Between the I / O boards of FIG. 2 to establish an IPC connection through a switch (BMP) , ATP, MMX, etc.)

For point-to-point connections, the cell route server can easily find the routing path of the switch structure, whereas for point-to-multipoint (multicast) connections, the cell route server has a complex switching algorithm. If the multicast cell is forwarded or replicated in the switch structure, the multicasting group must be designated and recorded on the switch 88 chip.

6 is a flowchart showing a point-to-point PVC setting procedure.

In step 6a, the PVC management unit analyzes the PVC setting command input by the operator in the user interface unit and transmits the PVC-related variables to the connection processing unit.

In step 6b, the access processor checks whether the VP / VC number to be set is acceptable through the resource manager. If not, it is notified through the user interface unit in step 6j.

In step 6c, the access processor receives a new access identifier to be set and sets a variable for setting a route related to an ATM-related driver and a switch structure to transmit / receive corresponding ATM cells in the access table.

In step 6d, the connection processor must initialize the AAL driver first to disassemble / assemble the upper level data into the ATM cell, and the VP corresponding to the UPC driver that can detect and eliminate the factors that may affect the QOS of another connection that is already set. Set the values for / VC, PCR / SCR, priority, etc.

In step 6e, the access processing unit requests the cell route server to set a corresponding VP / VC path so that the ATM cell can be routed through the ATM switch structure.

In step 6f, the switch cell route server receives the most efficient route tag value through the cell route database that manages the current occupied band and effective band of the inter-node link of the switch structure and sends it to the access processor. If there is no valid route path, it is notified through the user interface in step 6j.

In step 6g, the connection processor sends the output VP / VC along with the route tag value to the RT driver to enable VP / VC switching. When the connection setup is completed, the PVC management unit notifies the user interface unit in step 6h. The PVC management unit notifies the task requesting data transmission through the IPC message to complete the connection setup and starts data transmission and reception.

7 is a flow chart illustrating a point-to-multi-PVC setup procedure.

In step 7a, the PVC management unit analyzes the PVC setting command input by the operator in the user interface unit and transfers the variables related to PTMP PVC to the connection processing unit.

In step 7b, the access processor checks whether the VP / VC number to be set is acceptable through the resource manager. If not, it is notified through the user interface in step 7m.

In step 7c, the connection processor must distinguish whether the setup request connection is added to an existing PTMP connection or a new connection. In case of an additional connection, a previously designated multicast group number is obtained, and the following step 7g is performed.

In step 7d, the connection processor allocates a multicast ID to the new PTMP connection by referring to the multicast group table.

In step 7e, the access processor receives a new access identifier and sets a variable for setting a route related to an ATM-related driver and a switch structure to transmit / receive corresponding ATM cells in the access table. The connection table can be identified through the PTP / PTMP item whether the new connection is PTP or PTMP.

In step 7f, the connection processing unit sets a route value for one-way direction as it is a PTMP connection for establishing a route path of an ATM driver and a switch structure for transmitting / receiving a corresponding ATM cell as in a PTP connection.

In step 7g, the access processing unit efficiently routes the ATM cell to the multiport through the ATM switch structure, and requests the cell route server to set the path using an efficient tree algorithm so that the cell can be replicated.

In step 7h, the switch cell route server receives the most efficient route tag value through the cell route database that manages the current occupied band and effective band of the inter-node link of the switch structure and sends it to the access processor. If there is no valid route path, it is notified through the user interface in step 7m.

In step 7i, the switch cell route server sets the value of the destination port to the multicast number in the multicast group table of each unit switch element.

In step 7j, the access processor also sends a multicast group value, an input VP / VC value, and a VP / VC list value added to the multicasting group to the RT table so that the ATM cell can replicate the RT table.

When the PTMP connection setup is completed in step 7k, the PVC management unit notifies this through the user interface unit.

In step 7l, the connection processing unit notifies the task that has requested data transmission through the IPC message that the PVC management unit completes the PTMP connection setting and starts data transmission / reception.

In the point-to-multipoint PVC release, the PVC management unit of FIG. 4 receives a PTMP PVC release command from the operator, informs the connection processing unit of FIG. 4, deletes the corresponding connection identifier, and informs the resource management unit of FIG. 4 to restore resources. In addition, the connection processing unit of FIG. 4 also instructs the AAL driver, UPC, and RT driver to delete the corresponding VP / VC connection, and also requests the cell route database unit to release the occupied band of the set path of the switch structure.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by the equivalents of the claims.

BSC under ATM base can improve efficiency in setting PVC in ATM transmission section.

Claims (3)

In the permanent virtual connection setting device of the asynchronous transmission mode transmission section in the base station controller of the mobile communication system, An interprocessor communication connection setting unit which informs the permanent virtual access manager of initial information to establish an interprocessor communication channel between the boards when booting the boards forming the base station controller; A routing table driver for driving a table containing information about the routing of asynchronous transport mode cells in an asynchronous transport mode switch fabric; A connection processing unit managing connections by connection IDs of a connection table, setting a path between input / output boards for establishing a communication connection between processors, and notifying the routing table driver of related functions; A user interface unit for analyzing the persistent virtual access-related commands inputted by the operator to form a communication message between processors and informing the permanent virtual connection manager of this; An AAL5 / UPC driver configured to receive and set traffic variable values for each channel through the connection processor when the permanent virtual connection manager establishes a communication connection between system processors or establishes / releases a connection through the user interface unit; A permanent virtual access manager that performs a series of processes related to creating, managing, and releasing a persistent virtual access channel, A permanent virtual connection initialization unit which is created by a root task and creates a permanent virtual connection related task and initializes a permanent virtual connection related variable; A permanent virtual connection manager instructing the connection processing unit to assign a global connection identifier to a connection table and to have a connection establishment process according to a corresponding traffic variable when establishing a permanent virtual connection; A resource management unit for managing a permanent virtual connection state connecting the boards and the boards between the calling party and the called party of the transmission section of the base station controller; And a cell route server configured to set a path between input / output boards for establishing inter-processor communication connections through switches as a block for determining a route in a cell switch structure for each connection according to a routing request of a switch input / output board. A method for establishing a point-to-point permanent virtual connection of an asynchronous transmission mode transmission section in a base station controller of a mobile communication system, A first step of analyzing the permanent virtual access setup command input by the operator; A second process of checking whether the virtual path / virtual channel number to be set is acceptable; A third process of receiving a new connection identifier and setting a driver for transmitting / receiving a corresponding asynchronous communication mode cell and a variable for setting a route path of a switch structure in a connection table; In order to disassemble / assemble the upper level data into the asynchronous transmission mode cell, the asynchronous communication mode adaptation layer driver is initialized, and the values required to detect and remove factors that may affect the quality of service of another connection that are already set are used in the usage parameter control driver. The fourth process of setting up, A fifth step of requesting a cell route server to establish a route path, If the cell route server establishes a valid route path, it sets the destination port value of the multicast group table and informs the task that requested the data transmission to start the data transmission / reception. How to feature. A method for establishing a point-to-many virtual connection in asynchronous transmission mode transmission section in a base station controller of a mobile communication system, A first step of analyzing the permanent virtual access setup command input by the operator; A second process of checking whether the virtual path / virtual channel number to be set is acceptable; A third step of confirming whether the requested connection is added to an existing point-to-many connection or a new connection, and assigning a multicast ID by referring to the multicast group table if it is a new point-to-many connection; A fourth step of receiving a new connection identifier and setting a driver for transmitting / receiving corresponding asynchronous communication mode cells and a variable for setting a route path of a switch structure in a connection table; In order to disassemble / assemble the upper level data into the asynchronous transmission mode cell, the asynchronous communication mode adaptation layer driver is initialized, and the values required to detect and remove factors that may affect the quality of service of another connection that are already set are used in the usage parameter control driver. The fifth process of setting up, A sixth step of requesting a cell route server to establish a route path after obtaining a designated multicast group number in the third step or after performing the fifth step; If the cell route server establishes a valid route path, it sets the destination port value of the multicast group table and informs the task that requested the data transmission to start the data transmission / reception. How to feature.