KR0164118B1 - Lookup table control apparatus using lancam, method of lookup, connection setup, and connection cancelation using the former apparatus - Google Patents

Abstract

The present invention provides a look-up table control device for configuring a look-up table by combining LANCAM, which is currently used mainly for connection management and header conversion in 155 Mbps ATM (Asynchronous Transfer Mode) applications, with memory for use in 622 Mbps ATM applications. The present invention relates to a lookup, connection establishment, and disconnection method using the same. In order to use a conventional LANCAM in a 622Mbps ATM application, the lookup table functions required by an ATM application within one ATM cell time are minimized. In this way, the lookup table function required for the 622 Mbps application can be performed.

Description

Device for controlling lookup table using LANCAM, and method of lookup, connection setup and disconnection using it

1 is a connection relationship configuration diagram of the present invention.

2 is a block diagram of a look-up table control apparatus according to the present invention.

3 is a timing diagram of a LAN cam clock according to the present invention.

4 is a flowchart of performing a lookup function according to the present invention;

5 is a flowchart illustrating a connection establishment function according to the present invention.

6 is a flowchart of performing a disconnection function according to the present invention.

* Explanation of symbols for the main parts of the drawings

21: lookup table control selection unit 22: connection setting control unit

23: connection release control unit 24: lookup control unit

25: LAN cam write data and control signal selection unit 26: Memory address configuration unit

The present invention provides a look-up table control device for configuring a look-up table by combining LANCAM, which is currently used mainly for connection management and header conversion in 155 Mbps ATM (Asynchronous Transfer Mode) applications, with memory for use in 622 Mbps ATM applications. It looks at how to look up, establish a connection, and disconnect using it.

ATM is a connection-oriented system, where each connection is a virtual path identifier and a virtual channel identifier included in the header portion of an ATM cell that provides information about a particular connection. Is recognized by a combination of

LANCAM was originally used to obtain address match information in LAN applications that do not require high speed, but is increasingly being used for lookup table functions in 155Mbps ATM applications.

However, LANCAM has a disadvantage in that the driving speed is slow, the number of instructions required in an ATM application increases, and the amount of data that can be managed per connection is small.

Therefore, in order to increase the amount of data that can be managed per connection, a method of constructing a lookup table by combining LANCAM and memory has been introduced. The combination of LANCAM and memory makes up the lookup table, which not only increases the amount of data that can be managed per connection, but also reads the converted hair value from LANCAM during the lookup operation. LANCAM drive commands have been reduced.

However, in order to use such a LANCAM in a 622Mbps ATM application where the system clock speed is greatly increased, it is required to minimize the LANCAM driving clock and instructions.

Accordingly, the present invention provides a look-up table control device that minimizes instructions to use a conventional LANCAM in a 622 Mbps application so that look-up table functions required by an ATM application can be performed within one ATM cell time. The purpose is to provide a lookup, connection establishment, and connection release method using the same.

The apparatus of the present invention for achieving the above object comprises: look-up table control selecting means for selecting any one of a header value input from an external central processing unit connection means and an ATM function means; Connection setting control means for converting a header value selected by the look-up table control selecting means into a LANCAM input data type to generate and output a LANCAM control signal according to a LAN cam clock when performing connection setting; Connection disconnection control means for converting the header value selected by the lookup table control selecting means into a LANcam input data form to generate a LANcam control signal according to the LANcam clock when the connection is released; Look-up control means for converting the header value selected by the look-up table control selection means into a LAN cam input data form during the look-up table control to generate and output a LAN cam control signal according to the LAN cam clock; LAN cam write data and control signal selecting means for selecting one of the connection setting control means, the connection release control means, and the output of the lookup control means to output the LAN cam write data and the control signal to an external LAN cam; And a memory addresser configuring means for receiving a LANcam control signal from the LANcam write data and control signal selection means to determine when to perform a lookup function, extracting a match address storage portion from the LANcam weather data, and outputting an address to an external memory. It is characterized by including.

A look-up method for achieving the above object is a look-up method applied to a look-up table control apparatus using a LANCAM, wherein when a virtual path identifier / virtual channel identifier value extracted from a header is written to a comparison register of a look-up table A first step of storing an address matched with a virtual path identifier / virtual channel identifier value configured for connection in a status register; And reading the status register to obtain a match address used as a memory read pointer.

In order to achieve the above object, a connection setting method may include a virtual path recognizer / virtual channel identifier value to be established by an external central processing unit in a connection setting method applied to a look-up table control apparatus using a LANCAM. Writing to a register in a lookup table; And a second step of writing the register value to an empty space of a lookup table.

A connection release method for achieving the above object is a connection release method applied to a look-up table control apparatus using a LANCAM, the virtual path identifier / virtual channel identifier value to be established in the external central processing means Writing to a register in a lookup table; And a second step of deleting all of the same virtual path identifier / virtual channel identifier values that are connected in the lookup table.

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

1 is a connection relationship configuration diagram of the present invention, where 1 is a central processing unit connection unit, 2 is a lookup table control unit, 3 is a LANcam, 4 is a memory, 5 is an ATM function unit, and 6 is a lookup table.

The CPU 1 transmits a virtual path identifier / virtual channel identifier value to be set and released to the lookup table controller 2 when the connection establishment function and the connection release function are performed.

The ATM function unit 5 extracts the virtual path identifier / virtual channel identifier value from the cell input when performing the lookup function and transfers the value to the lookup table controller 2.

The lookup table control unit 2 selects data and control signals input to the LAN cam 3 according to each lookup table function and configures a memory access address accordingly.

The LANcam 3 stores the virtual path identifier / virtual channel identifier values established for the connection and then looks up the address value of the match that is matched when the extracted virtual path identifier / virtual channel identifier is input to the cell header. Output to the table control unit 2.

The memory 4 stores various data corresponding to the virtual path identifier / virtual channel identifier set in connection with the LAN cam 3.

2 is a block diagram of a lookup table control apparatus according to the present invention, in which 21 is a lookup table control selector, 22 is a connection setup controller, 23 is a disconnection controller, 24 is a lookup controller, and 25 is a LANcam write data and control signal selection. 26 denotes memory address components.

The lookup table control selector 21 inputs the header value from the central processing unit connection unit 1 or selects a header value when performing the connection establishment function and the disconnection function, or the header value input by the ATM function unit 5 when performing the lookup function. Select.

The connection setting control unit 22 converts the header value selected by the lookup table control selecting unit 21 into a 16-bit LANCAM input data type when performing the connection setting, and according to the LANCAM clock, the LANCAM control signal. (MI, FI, EC, etc.) are generated and transferred to the LANCAM write data and control signal selector 25.

The connection release control unit 23 converts the header value selected by the lookup table control selector 21 into a 16-bit LANCAM input data type when performing the connection release, and according to the LANCAM clock, the LANCAM control signal. (MI, FI, EC, etc.) are generated and transferred to the LANCAM write data and control signal selector 25.

The look-up control unit 24 converts the header value selected by the look-up table control selector 21 into a 16-bit LANCAM input data form when the look-up table is controlled, according to the LANCAM clock signal. MI, FI, EC, etc.) are generated and transferred to the LANCAM write data and control signal selector 25.

In the LANCAM write data and control signal selector 25, the connection setting control unit 22, the connection release unit 23, and the lookup control unit according to the operating state of the central processing unit connection unit 1 or the ATM function unit 5. One of the outputs of 24 is selected to transfer the LAN cam write data and the control signal to the LAN cam 3.

The memory address configuration section 26 is provided from the LANCAM write data and control signal selection section 25.

The LANCAM control signal is input to determine when to perform the lookup function, and the fetch address storage portion is extracted from the LANCAM read data read from the status register of the LANCAM 3 and transferred to the memory 4 as an address.

When performing the lookup function, the header value extracted from the ATM function unit 5 is input to the LANcam 3 through the lookup control unit 24. The data read from the LAN cam 3 is used as the address for accessing the memory as it is through the memory address structure section 26, and then the contents of this address are output and used as the converted header.

When performing the connection setting function, the header value input from the central processing unit connection unit 1 is input to the LAN cam 3 through the connection setting control unit 22. At this time, the converted header value to be written to the memory 4 is input directly from the central processing unit connection unit 1 without going through the lookup control unit 24.

When performing the disconnection function, the header value to be released from the central processing unit connection unit 1 is input to the LANcam 3 through the disconnection control unit 32.

3 is a timing diagram of a LAN cam clock according to the present invention.

The main functions of a lookup table in an ATM device are a lookup function, a connection establishment function, and a disconnection function.

In order to ensure that each function can be performed independently even when cells are continuously input, one cell time is divided so that the lookup function is basically performed at the first part, and the ATM function operation is performed at the remaining time or from the central processing unit. Make sure to set up or disconnect the connection.

In a 622 Mbps ATM device, one cell's time is approximately 695 ns, and the driving clock of the currently used LANCAM operates at 90 ns periods. Therefore, the number of LANCAM instructions that can be executed in one cell time is limited to a maximum of seven.

Command configurations that minimize the number of instructions required to perform each function to meet these constraints are as follows. One command is executed sequentially for each function.

4 is a flowchart of performing a lookup function according to the present invention.

The lookup command consists of:

DW 0XCCCC MI_HI FI_LOEC_HI

DW 0XFFFF MI_HIFI_LOEC_LO

CR 0X0000 MI_HIFI_LOEC_LO

CR 0X0000 MI_HIFI_LOEC_HI

Looking at the order of performing the lookup function, the virtual path identifier / virtual channel identifier value extracted from the header is written to the comparison register of the lookup table (41). At this time, the address matched with the virtual path identifier / virtual channel identifier value for which connection is established is stored in the status register.

The status register is then read (42) to obtain a match address that is used as a memory read pointer.

5 is a flowchart illustrating a connection establishment function according to the present invention.

The configuration of the connection setup command is as follows:

DW 0X1111 MI_HIFI_LOEC_HI

DW 0X3333 MI_HIFI_LOEC_HI

CW MOV_NF, CR, V MI_HIFI_LOEC_HI

Referring to the execution order of the connection establishment function, the CPU writes the virtual path identifier / virtual channel identifier value to be established in the register in the lookup table (51).

The register value is then written to the empty space of the lookup table (52).

6 is a flowchart of performing a disconnection function according to the present invention.

The configuration of the disconnect command is as follows:

DW 0X0000 MI_HIFI_LOEC_HI

DW 0X0000 MI_HIFI_LOEC_HI

CW VBC_ALM, E MI_HIFI_LOEC_HI

Referring to the configuration of disconnection command, the CPU writes the virtual path identifier / virtual channel identifier value to be established in the register in the lookup table (51).

Thereafter, all of the virtual path identifier / virtual channel identifier values connected in the lookup table are erased (62), which are the same as the virtual path identifier / virtual channel identifier values recorded in the register.

The present invention as described above has the effect of performing the lookup table function required for a 622Mbps application device by minimizing the number of LANcam driving commands.

Claims (4)

Look-up table control selecting means (21) for selecting any one of a header value input from an external central processing unit connecting means (1) and an ATM function means (5); Connection setting control means 22 for converting the header value selected by the look-up table control selecting means 21 into a LANCAM input data form and generating and outputting a LANCAM control signal according to the LAN cam clock when performing connection setting. ; Disconnection control means (23) for converting the header value selected by the lookup table control selection means (21) into a LANcam input data form to generate a LANcam control signal according to the LANcam clock when the connection is released; Look-up control means (24) for converting the header value selected by the look-up table control selecting means (21) into a LAN cam input data form to generate and output a LAN cam control signal according to the LAN cam clock during the look-up table control; LANcam write data for selecting one of the connection setting control means 22, the connection release control means 23, and the output of the lookup control means 24, and outputting the LANcam write data and the control signal to the external LANcam 3; And control signal selecting means 25; And receiving a LAN cam control signal from the LAN cam write data and control signal selecting means 25 to determine when to perform a lookup function, extracting a match address storage portion from the LAN cam read data read from the LAN cam 3, and storing an external address. A lookup table control device using a LANCAM, characterized by comprising a memory addressing means for constructing means 26 for outputting to a memory 4 of the memory. In a lookup method applied to a lookup table control apparatus using a LANCAM, when a virtual path identifier / virtual channel identifier value extracted from a header is written to a comparison register of a lookup table, a virtual path identifier having a connection setting is established. A first step 41 in which an address matched with a virtual channel identifier value is stored in a status register; And a second step (42) of reading the status register to obtain a match address used as a memory read pointer. A connection setting method applied to a lookup table control apparatus using a LANCAM, the first step of writing a virtual path identifier / virtual channel identifier value to be established by an external central processing unit in a register in a lookup table 51); And a second step (52) of writing the register value to an empty space of a lookup table. In the connection release method applied to a lookup table control apparatus using a LANCAM, a first step of writing a virtual path identifier / virtual channel identifier value to be established by an external central processing unit in a register in a lookup table ( 61); And a second step (62) of deleting all of the virtual path identifier / virtual channel identifier values that are connected in the lookup table that are identical to the virtual path identifier / virtual channel identifier values recorded in the register. The disconnection method characterized by the above.