KR0175578B1 - Cell Relay and Ed / Drop Device and Method in Active Unidirectional Dual Bus - Google Patents

Abstract

The present invention relates to a cell relay and an ed / drop device and a method in a unidirectional duplex bus, using a simple multiplexing and a router structure rather than a switch structure to provide a requested service at a low price and to transfer service data between terminals. In order to provide a relay function and a cell add / drop function by providing a relay function and a cell add / drop function by cell transfer between end nodes, an intermediate film, and a head node on the subscriber side, a routing information is connected to a microprocessor. The processor connection unit that receives and transmits and receives control and status information in the device and the routing field among 56 bytes of data requested to be transmitted from the network are analyzed and dropped to the AAL layer or to the subscriber. 3 bytes of tag are attached to the cell requesting delivery from AAL layer and transferred to ATM layer. Direction and AAL cell relay connection portion and the nostalgia cell relay and the AAL connection portion and a hardware configuration in which the function of, but is the same, characterized by consisting of a subscriber effort cell relay connection data for the subscriber and effort AAL connection.

Description

Cell relay and ed / drop device and method in active unidirectional dual bus

1 is a bus-type subscriber network configuration.

2 is a block diagram of a cell relay and an add / drop device of the present invention.

3 is a cell relay and add / drop processing flow chart of the present invention.

4 is a detailed configuration diagram of FIG.

* Explanation of symbols for the main parts of the drawings

21 processor connection 22 network cell relay and AAL connection

23: subscriber cell relay and AAL connection

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for relay and drop / drop in a unidirectional dual bus, and more particularly, in the case of building a broadband service network in a home or small business in the form of a bus in a broadband integrated information network, The present invention relates to an ATM cell relay and an add / drop method and apparatus for relaying a delivered cell to another ATM layer or transmitting / receiving a cell to an AAL (ATM Adaptation Layer) layer.

Recently, with the development of communication technology, users are demanding a variety of high-quality services, as well as continuous services such as voice and video services, as well as burrs such as high-speed data services such as file transfer and real-time video services with variable bit rates. In order to provide the services of the Chongsung province on the same link, an ATM-based Broadband Intebrated Services Digital Network (B-ISDN) has emerged.

Conventional devices for constructing a broadband integrated telecommunication network are more than a medium-scale to provide broadband services to a private network or a large number of areas, and to develop large-scale switches that will be important to a national backbone network rather than to develop devices for providing home or direct subscriber services. The focus has been on device development.

Most of these devices have been developed in a switch structure, which is used for inter-regional traffic transmission and reception requiring large input and output, but in ring or bus structures for use in homes or small businesses that use direct services. The following disadvantages exist when compared to the multi-access configuration.

1. When the switch structure device is connected to each service terminal by transmission line, all the lines should be connected one-to-one to each terminal in the switch. Therefore, the transmission line takes more than the ring or bus type, causing a price increase. In this case, it is more difficult to maintain or operate than simple multiplexer or bus type by adopting a complicated switch structure. 3. When access port is needed, multi-access simply adds a terminal between the previous terminal or between terminal and terminal. In case of switch type, it is necessary to install by switch unit for expansion of port, thus causing unnecessary port waste.

Figure 1 shows a subscriber network configuration of the bus to which the present invention is applied. In order to configure a service delivered from the network in the form of a bus, a head node 11, an intermediate node 12, and an end node 13 are configured.

The head node terminates the protocol of the network side and performs a function of connecting the functions of terminals corresponding to the intermediate node and the end node to the network. The cell relay function is required to transfer cells from each intermediate node 12 to other intermediate nodes 12 and end nodes 13, and each node requests a service to the ATM adaptation layer to provide a requested service. The ability to deliver the cell (cell add and drop function) is required.

SUMMARY OF THE INVENTION The present invention devised according to the present invention provides a cell relay and an ed / drop apparatus and method for transferring service data between terminals to provide a requested service at a low price using a simple multiplexing and router structure rather than a switch structure. There is this.

In order to achieve the above object, the present invention provides a cell relay function that is located between an ATM layer and an AAL layer and connected to a microprocessor to transfer a cell from each intermediate node to another intermediate node and an end node constituting an active unidirectional bus structure. A cell relay and drop / drop device for providing a cell add and drop function for transferring a cell between the AAL layer and an ATM layer to request a service from each node and to provide a requested service, wherein the cell relay and the drop / drop device connect to and route the microprocessor. 56 bytes of data requesting the transmission from the network through the processor connection unit for receiving the information and transmitting and receiving control and status information in the device to the network cell relay and the AAL connection unit and the subscriber cell relay and the AAL connection unit. To compare and drop only the routing field in the AAL layer Determining whether to forward or copy, and comparing the processor connection with the network-oriented cell relay and AAL connection function that transmits the tag to the ATM layer by attaching a tag of 3 bytes to the cell to request delivery from the AAL layer. It is a subscriber-oriented cell that analyzes and decides whether to drop, forward, or copy to the AAL layer, and attaches a 3-byte tag to the cell requesting delivery from the AAL layer. It is characterized by consisting of a relay and the AAL connection.

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

Prior to the description, the cell relay and the add / drop devices are located between the ATM layer and the AAL layer to deliver 56 bytes of data transferred from the ATM layer to the AAL layer (REOP) or relay to another ATM layer. It is a kind of medium access control (MAC) device that routes the cell from the layer to the ATM layer in units of 56 bytes.

The cell relay and the ed / drop devices are located above the physical layer and the ATM layer having the same structure in order to form a unidirectional dual bus. 1) ATM requesting transmission from the network (or subscriber) to the subscriber (network). 3) Cell copy function for relaying data in cell form or 2) Deliver data from each direction to AAL layer, 3) Cell copy function to provide one-to-multiple services, and 4) Routing of 3 bytes to cell requiring delivery in AAL layer In addition to cagrears, it delivers to the ATM layer and 5) discards unregistered cell data.

2 is a block diagram of the upper layer of the cell relay and the add / drop device according to the present invention.

The cell relay and the add / drop device 100 may be connected to the microprocessor 25 to receive routing information, and to transmit and receive control and status information within the device. Only the routing field of 56 bytes of data is compared and analyzed to determine whether to drop to the AAL layer 27 or forwarded to the subscriber, and a 3-byte tag is sent to the cell for which the AAL layer 27 requests delivery. The routing field of the network cell relay and AAL connection unit 22 to be transmitted to the ATM layer 24 and the 56-byte data requested to be delivered from the subscriber is analyzed and dropped to the AAL layer 28, or to the network. It is composed of a subscriber-oriented cell relay and an AAL connection unit 23 which decides whether or not to deliver, and attaches a tag of 3 bytes to the cell requesting delivery from the AAL layer 28 and delivers it to the ATM layer 26.

The network relay and AAL connection unit 22 and subscriber-oriented cell relay and AAL connection unit 23 have the same hardware structure, and only adjust the routing path according to the connected position to transfer data to the network and subscriber.

3 is a flow chart of ATM cell relay and ED / Drop according to the present invention, which inputs data from each layer while inputting a mask byte, an AAL routing selector, a one-to-multiple routing selector, and a multiplexing sequence processor during the initial and process steps. If allowed (301), data entry from the ATM and AAL layers begins. After extracting the routing identifier of 3 bytes from the data input from the ATM layer (302) (303), comparing the routing identifier with the same value as the AAL routing selection field (304), and dropping the cell to the AAL layer if it is the same value. (305), if the routing identifier is not the same value of the AAL routing selector, compares it with the one-to-multiple routing selector (306) and if it is the same value, copies the cell and passes the cell to the AAL layer (305) as well as to another node. In operation 307, the cell is stored in a relay buffer to deliver the cell.

If the routing identifier has a different value from the one-to-multiple routing selector, when the device is used at the end node, the input cell is discarded (309), and in the case of the intermediate node or the head node, the relay is transmitted to another node. The cell is stored in the buffer (307).

When data is input from the AAL layer (310), the signal is multiplexed with the relay cell in accordance with the order of multiplexing set by the processor (311), and after inserting a routing tag, the data is output to the ATM layer and transmitted to other nodes. (312).

The configuration and operation thereof will be described with reference to the detailed block configuration of FIG. 4, which is one embodiment of the present invention.

In the detailed block structure of the present invention, the first and second ATM receiving controllers 401 and 406 extracting three bytes corresponding to routing information from 56 bytes of data transmitted from the ATM layer and storing only cells in a FIFO buffer. First and second routers 402 and 407 for determining a transfer path such as AAL layer, relay, or discarding the cell stored in the packet buffer from the extracted 3 bytes of routing information, and inputted from each router. First and second cell transmitters 404 and 408 for extracting a cell's delivery path and storing the cells in the corresponding buffer buffers, and first and second cell multiplexers 404 and 409 for multiplexing drop cells and relay cells; Network relay and AAL connections 22 including first and second ATM transmission controllers 405 and 410 for transmitting the cells and relay cells transmitted from the AAL layer to the ATM layer; 23), the processor connection portion 21 and A plurality of buffers 411, 412, 413, 414, 415 and 416 for storing only cells are added.

Referring to the operation of the present invention by such a configuration as follows.

First, the processor connection unit 21 reports the state of the network / subscriber cell relay and the AAL connection units 22 and 23 to the microprocessor 25, and receives alarm control logic for processing the register and alarm when receiving the appropriate control. It consists of.

Each register has a register for controlling network direction and a register for controlling subscriber direction, and extracts and compares 1 byte of data corresponding to routing field among 56 bytes of data transferred from ATM layer It consists of a register for routing to each bit, a register for determining comparability for each bit, a register for controlling each envelope, and a register for reporting an alarm state of the envelope.

The first and second ATM receiving controllers 401 and 406 extract the routing field 56 bytes input data transmitted from the ATM layer in synchronization with the data input control signal, and then transfer the routing field to the first and second routers 402 and 407. Only pure cells, except for those, are stored in the packets 411 and 414.

Only three bytes of the routing field of the 56 bytes are extracted from the data requested to be transferred by the ATM layer, and the buffer write data of 53 bytes is stored in the buffers 411 and 414 by the write write control signal.

The extracted routing field is transferred to the router and the internal operation of the ATM receiver controller is controlled sequentially by the counter.

The routing identifiers transmitted from the first and second ATM reception controllers 401 and 406 to the first and second routers 402 and 407 are converted into routing direction determiners after the following process. When the bits to be compared are selected by the mask byte transferred from the processor connection unit 21, the AAL routing selector and the one-to-multiple routing selector delivered from the microprocessor connection 21 and the first and second ATM reception controllers 401 and 406 are transmitted. The routing identifiers are compared bit by bit to determine whether to forward, broadcast, or relay the AAL layer.

If the routing identifier has the same value as the AAL routing selector, the cell is routed to the AAL layer. If the routing identifier has the same value as the one-to-multiple routing selector, the cell is routed to the relay and the AAl layer.

When the cell relay and the ed / drop device of the present invention are used for the head node and the intermediate node, If the routing identifier has a different value from the AAL routing selector but the same value as the one-to-multiple routing selector, It is relayed when it has a different value from each routing selection operation. When it is used for an end node, the cell is discarded when the following conditions are satisfied.

The first and second cell transmitters 403 and 408 receive the routing direction determiners and buffers of the buffers 413, 412, 415 and 416 inputted from the first and second routers 402 and 407, and store them in the buffers 413, 412, 415 and 416. The data of the buffers 411 and 414 are read as a signal, and the state of the buffer is transmitted to the processor connection unit 21. The routing direction determiner consists of a 2-bit buffer selector and a 1-bit buffer selector valid period indicator.

The first and second cell transmitters 403 and 408 receive the relay / discard determinator from the processor connection unit 21 during the initialization process, and the buffer selector valid period indicator of the routing direction determiner is enabled, thereby disabling all the buffer selectors of 2 bits. If enabled, it determines whether to relay or discard the cell.

In addition, each buffer 412, 413, 415, 416 detects when the buffer becomes full and prevents further data from being used in the buffers 412, 413, 415, 416 and informs the processor 25 of the full state.

The first and second cell multiplexers 404 and 409 have a function of selecting one of a cell and a relay cell for which transfer is requested from the AAL layer and a function of reading a buffer in which the selected cell is stored. When the cell forwarder 403 or 408 of the AAL layer and the other side requests cell delivery, the cell multiplexer 404, 409 receives one of the packet and relay packet buffers 413 and 416 existing in the AAL layer according to a preset priority. At the same time as selecting the buffer, the cell validity interval indicator reads whether or not the first and second ATM transmission controllers 405 and 410 can receive the cell.

If the cell transfer is possible to the ATM transmission controllers 405 and 410 by this reading, the corresponding buffer is read and transmitted to the ATM transmission controllers 405 and 410.

The first and second ATM transmission controllers 405 and 410 use the selector of the cell multiplexer described above to make an ATM interface control function and a 3-byte front end of the 53-byte cell transmitted from the output storage buffer. A tag insertion function for inserting a routing tag, and a function for transmitting whether a cell can be delivered to the first and second cell multiplexers 404 and 409.

When the cell start and the cell validity period indicator are asserted in the first and second cell multiplexers 404 and 409, the first and second ATM transmission controllers 405 and 410 attach a 3-byte tag to 53-byte cell data. It is inserted at the front end and delivered to the ATM layer together with the data output start signal and the data valid interval indication signal.

The routing tag inserted during data transfer to the ATM layer is filled with a preset value by the microprocessor connector 21.

As described above, the present invention can provide a requested service at a low price by using a simple multiplexing and router structure, and can provide service data between terminals.

Claims (9)

It is located between the ATM layer and the AAL layer and connected to the microprocessor. The cell relay function delivers cells to other intermediate nodes and end nodes in each intermediate node constituting the active unidirectional bus structure. A cell relay and a drop / drop device for providing a cell add and drop function for transferring a cell between the AAL layer and an ATM layer to provide a device, the cell relay and the drop / drop device, which are connected to the microprocessor to receive routing information and control and status in the device. Comparing and analyzing only the routing field of 56 bytes of data requested to be transmitted from the network through the processor access means for transmitting and receiving information from the network cell relay and AAL access means and the subscriber cell relay and AAL access means. Whether to drop to the AAL layer, forward to subscriber, copy A network-oriented cell relay and an AAL access means for attaching a 3-byte tag to the cell requesting delivery in the AAL layer and forwarding the same to the ATM layer, and at the subscriber side through the processor access means. Compare and analyze only routing field among 56 bytes of data requested for delivery, and decide whether to drop, forward or copy to AAL layer, and 3 bytes of tag in cell that requested delivery in AAL layer Cell relay and ed / drop device in a unidirectional dual bus, characterized in that consisting of the subscriber-oriented cell relay and the AAL connection means to transfer to the ATM layer attached to. The cell relay and add / drop device of claim 1, wherein a plurality of FIFO buffers for storing only cells are missing. The ATM reception controller according to claim 1 or 2, wherein the network-directed cell relay and the AAL access unit extract 3 bytes corresponding to routing information from 53 bytes of data transmitted from an ATM layer and store only cells in the buffer. And a router for determining a transfer path of a cell stored in the buffer from the extracted 3 bytes of routing information, and a cell transfer for extracting a transfer path of a cell input from the router and storing the cell in each corresponding buffer. A unidirectional duplex comprising a cell multiplexer for multiplexing the drop cell and the relay cell delivered from the cell transmitter, and an ATM transmission controller for delivering the cell and relay cell delivered from the AAL layer to the ATM layer. Cell relays and add / drop devices on the bus. 3. The ATM receiver according to claim 1 or 2, wherein the subscriber cell relay and the AAL access means extract 3 bytes corresponding to routing information from 53 bytes of data transmitted from the ATM layer, and store only cells in the buffer. A controller, a router for determining a transfer path of a cell stored in the buffer from the extracted 3 bytes of routing information, and a cell for extracting a transfer path of a cell input from the router and storing the cell in each buffer. A unidirectional duplex comprising a transmitter, a cell multiplexer for multiplexing the drop cell and the relay cell delivered from the cell transmitter, and an ATM transmission controller for delivering the cell and the relay cell delivered from the AAL layer to the ATM layer. Cell relays and add / drop devices on the bus. The method of claim 1, wherein the processor access means comprises a register for reporting the state of the cell relay and the AAL connection means to the microprocessor, receiving a proper control, and an alarm control logic for processing the alarm when an alarm occurs. Cell relays and ed / drop devices on dual buses. 6. The processor according to any one of claims 1, 2 and 5, wherein the processor connecting means comprises: a register for controlling the network cell relay and the AAL connection means, a register for controlling the subscriber cell relay and the AAL connection means; A register for routing to the corresponding buffer after extracting and comparing 1 byte of data corresponding to a routing field among 56 bytes of data transferred from the ATM layer, and a register for determining comparability for each bit, and Cell relay and ed / drop device in a unidirectional dual bus comprising a register for controlling the buffer and a register for reporting the alarm status of the buffer. 5. The cell relay and ed / drop device of claim 4, wherein the cell transmitter is characterized in determining whether to relay or discard the cell. 5. The ATM transmission controller of claim 4, wherein the ATM transmission controller transmits an ATM interface control function for making a connection signal with an ATM layer, a tag insertion function for inserting a 3-byte routing tag in front of a 53-byte cell, and whether a cell can be delivered. Cell relay and ed / drop device in a unidirectional dual bus, characterized in that. A cell located between the ATM layer and the AAL layer, connected to a microprocessor, a plurality of buffers, and transferring a cell from each intermediate node 12 to another intermediate node 12 and an end node 13 constituting an active unidirectional bus structure. In the method using a cell relay and a drop / drop device that provides a cell function and a drop function for transferring a cell between the AAL layer and ATM layer to request a service and provide the requested service at each node, A first step of extracting a 3-byte routing identifier from data input from the ATM layer, a second step of comparing whether the extracted routing identifier has the same value as an AAL routing selector, and a comparison between the second step If the same value, the routing identifier is not the same value as the AAL routing selector by comparing the third step with the cell drop to the AAL layer and the second step. Compared with the one-to-multiple routing selector, the fourth step of copying a cell and transferring the cell to the AAL layer as well as storing the cell in a relay buffer to transfer the cell to another node, and comparing the fourth step. If the routing identifier has a different value from the one-to-multiple routing selector, the cell relay and the drop / drop device are discarded when the cell relay and the drop / drop device are used in the end node, and the cell is used as another node when the intermediate node or the head node is used. A fifth step of storing the cell in the relay buffer to transfer the data; if data is inputted from the ALL layer, the cell is multiplexed with the relay cell in the order of multiplexing set by the processor, and then a routing tag is inserted and then the data is transmitted to the ATM layer. To the unidirectional dual bus, comprising a sixth step of outputting another Nord data. Cell Relays and Ed / Drop Methods.