KR0139585B1 - Apparatus for atm receiver having a single-ring structure - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a giga-class ATM receiver under a single ring structure, and includes first buffer means (FIFO10-13) for receiving a signal from the physical layer receiver 31 and storing and sorting data in units of a first predetermined number of octets. And a cell receiver 32 for determining whether the data (cell) stored in the first buffer means FIFO10-13 is the data transmitted to the own station or the data to be received by another node on the ring, and the data transmitted to the own station. The second buffer means (FIFO14-17) for storing the first predetermined number of octets, and the data transferred from the second buffer means (FIFO14-17) in the first predetermined number of octets. And a third buffer means (FIFO18) for receiving data from the multiplexer 33 and transmitting the data from the multiplexer 33 to the ATM receiver 34. Minimize the loss in the B-ISDN network There is an effect that can be efficiently used in a system for multiplexing cells at high speed.

Description

Giga-class ATM receiver under single ring structure

1 is a cell format diagram between a subscriber station;

2 is a block diagram of a subscriber access network to which the present invention is applied and a subscriber access network,

3 is a block diagram showing the overall configuration of a giga-class ATM receiver according to the present invention;

4 is a diagram illustrating a connection structure of a cell receiver;

5 is a connection structure diagram of a multiplexer.

* Explanation of symbols for main parts of the drawings

31: physical layer receiving unit 32: cell receiving unit

33: multiplexer 34: ATM receiver

The present invention relates to a receiving apparatus of a communication device for connecting a subscriber node of a functional module that conforms to the user-network interface specification of the broadband integrated telecommunication network recommended by ITU-T, an international standard organization, to a ring access subscriber network. The present invention relates to a Giga-class ATM receiver under a single ring structure in which a connection with a subscriber node is connected at a low speed (155 Mbps) and a connection on a ring at a high speed (1.25 Gbps).

In general, B-ISDN is standardized by ATM (Asynchronous Transfer Mode) to provide various types of services and wide bandwidth to users in a flexible and scalable manner. In order to accommodate such various services, the broadband integrated telecommunication network should replace all existing subscriber networks with optical cables, unlike the narrowband integrated telecommunication network (N-ISDN), which represents a significant proportion of the total investment cost of the network. Imply that it occupies a quantity.

In the broadband integrated information communication network, the subscriber network can be configured in such a manner that a separate cable is installed for each subscriber and a single cable is shared by a plurality of subscribers like a conventional telephone network. It is easy to implement the former, but the cable is expected to take a lot. If the subscriber network is configured in the latter way, it is economically configurable because several subscribers share one optical cable and can efficiently accommodate the broadcasting service that is expected to be mainstream of the initial broadband integrated telecommunication network service. There is an advantage.

However, since the conventional ATM cell receiver under the single ring structure is a device that transmits and receives data at 300Mbps, cell congestion delay and system performance decrease due to congestion of data on the ring. That is, there is a problem that the bandwidth of the ring using the optical fiber is not sufficiently used.

In addition, if you want to provide video or other video services in a network structure where several transmission nodes exist, you can provide a service by providing a transmission speed of about 300Mbps using an existing transceiver. Since the full speed is not available, there is a problem in that the number of nodes that can be connected to the ring structure, that is, the number of subscribers and the quality of service are limited.

Accordingly, the present invention has been made to solve the above problems of the prior art, and in the latter scheme, that is, in designing a broadband access network subscriber access network having a ring shape, the subscriber node is connected to the subscriber node in order to access the subscriber network. The purpose of the present invention is to provide a giga-class ATM receiver under a single ring structure capable of providing 155 Mbps and 1.25 Gbps for a ring.

The present invention for achieving the above object is provided with a Mullah layer receiving unit for receiving a signal from a subscriber access network of a single ring type operating at high speed, and a higher layer ATM receiving unit for transmitting a signal to a subscriber operating at a low speed An ATM cell receiver comprising: first buffer means for receiving a signal from the physical layer receiver and storing and sorting data in a first predetermined number of octets; Cell receiving means for discriminating whether data (cell) stored in said first buffer means is data transmitted to a local station or data to be received by another node on a ring; Second buffer means for storing the data transmitted to the local station in the first predetermined number of octets; Multiplexing means for converting the data transferred from said second buffer means in said first predetermined number of octets into a byte stream of a second predetermined number of octets; And third buffer means for receiving data from the multiplexing means and transmitting the data to the ATM receiver.

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

Communication between subscriber access devices operates in 56-octet module communication cell unit consisting of 4-octet header and 52-octet payload based on ATM cell as shown in the cell format diagram between subscriber transceiver devices of FIG. 1. 4 octets are used as the base. Such a communication function between the access devices is performed in the lower ATM layer of the protocol reference model of the broadband integrated information communication network user-network interface.

2 is a diagram of a subscriber access network to which a subscriber access network according to the present invention is applied and a subscriber access network operating at 1.25 Gbps to a subscriber operating at 155 Mbps to access a subscriber node by a giga-class ATM cell receiver according to the present invention. Shows the receiver's connection structure.

3 is a block diagram showing the overall configuration of a giga-class ATM receiver according to the present invention.

First, in the overall configuration of the ring access device, a total of 18 first-in, first-out buffers (FIFOs) are used to transmit and receive data (cells) and data of the upper layer (ATM layer) of the corresponding node on the subscriber access network under the ring structure. Each FIFO has a capacity of 512K bytes and can provide transmission rates up to 60MHz.

Accordingly, the first buffer unit FIFO10-13, which receives the signal from the physical layer receiver 31 that receives the signal from the subscriber access network having a single ring type, operates at a high speed, and stores and sorts the data in units of four octets. And a cell receiver (IMC-Rx) 32 for determining whether the data (cell) stored in the first buffer unit FIFO10-13 is the data transmitted to the own station or the data to be received by another node on the ring. A second buffer unit FIFO14-17 for storing data transmitted in 4 octet units and data transferred in 4 octet units from the second buffer unit FIFO14-17 into a byte stream of 1 octet. A multiplexer 33 and a third buffer FIFO18 for receiving data from the multiplexer 33 and transmitting the data to the ATM receiver 34 to transmit a signal to a subscriber operating at a low speed.

Looking at the general contents of the present invention configured as described above are as follows.

First, the physical layer receiver 31 receives a signal transmitted at 1.25 Gbps through an optical fiber, and the cell receiver 32 may process data in eight bits, that is, four octets, in the first buffer unit FIFO10-13. The G-TAXI chip is configured to have sufficient bandwidth for the user's requirements using the G-TAXI chip to accommodate the delay-sensitive services and services in real time.

All data on the ring are first stored in the first buffer unit FIFO10-13 through the physical layer receiver 31 and transmitted to the corresponding node. The data is transferred to the ATM receiver 34, which is the upper layer, and the node is transmitted. If it is not the receiving node to receive the data, the data is stored in the bypass buffers FIFO6-FIFO9, and then multiplexed through the cell transmitter with the 1: 7 ATM cell ADM function and forwarded to neighboring nodes on the ring. In this way, it is possible to determine whether the data (cell) read through the ring is transmitted to the local station or data that other nodes on the ring should receive and store in the FIFO6-FIFO9 or the second buffer unit (FIFO14-17). The part to perform is the cell receiver 32. In the case of general point-to-point data transmission, the cell receiver 32 uses a receiver-side elimination technique in which the node receiving the data removes the data from the ring. For this reason, the sending node uses a sending side elimination technique to remove data from the ring.

4 is a diagram illustrating a connection structure of a cell receiver. First, data received through the optical module receiver is stored in the first buffer units FIFO10-13. Once one cell is accumulated in the first buffer unit FIFO10-13, the FIFO13 notifies the cell receiver 32 that there is data received using the FIFO13_PAE * (Active HIGH) signal. When the FIFO13_PAE * signal is transmitted from the FIFO13, the cell receiver 32 uses the FIFO13_REN * (Active LOW) and FIFO13_OE * (Active LOW) signals for each of four octets of data stored in the first storage unit (FIFO10-13) at a time. Read at a rate of FIFO13_RCLK * (31.25MHz). The first four octets read among the received cells correspond to the header of the cell, and the cell receiver 32 stores the received cell in the FIFO6-FIFOO9 based on the four octets in the second storage unit (FIFO14-17). Will be determined. In case of an ATM cell transmitted to a local station, the cell receiver 32 stores the data read from the first storage unit FIFO10-13 at a rate of FIFO_WCLK (31.25MHz) using the FIFO17_WEN (Active LOW) signal. Store in the part (FIFO14-17). In the case of data to be transmitted to another node on the ring, the cell receiver 32 uses the FIFO9_WEN (Active LOW) signal to read the data read from the first storage unit FIFO10-13 to a speed of FIFO_WCLK (31.25MHz). FIFO6-performs the function of saving to FIFO9. The data read rate from the first storage unit (FIFO10-13) is 31.25MHz, and once read, it reads in 4 octets, so the theoretical receive rate is 1.25Gbps. However, since the 3-octet header is added to the actual 53-octet ATM cell, the actual rate of receiving the ATM cell is 1.25Gbps * (53/56), that is, 1.183Gbps.

5 is a diagram illustrating a connection structure of the multiplexer. The ATM cell received at the rate of FIFO_WCLK (31.25 MHz) through the cell receiver 32 is stored in the second storage unit FIFO 14-17 but is transferred to the ATM receiver 34 which is a higher layer. Since the data to be transmitted should be transmitted in units of one octet rather than units of four octets, the multiplexer 33 is responsible for converting the data transmitted in units of four octets into a byte stream of one octet. If a certain number of bytes are stored in the buffer, the FIFO17 notifies the multiplexer 33 that data has been received through the FIFO17_PAE * (Active HIGH) signal. When the multiplexer 33 receives the FIFO17_PAE * signal, the multiplexer 33 uses the FIFO14_REN * (Active LOW), FIFO14_OE * (Active LOW), FIFO15_REN *, FIFO15_OE *, FIFO16_REN *, FIFO16_OE *, FIFO17_REN *, and FIFO17_OE * signals. Read data sequentially from negative (FIFO14-17) at FIFO17_RCLK (19.44MHz) speed. FIFO17-FIFO14-FIFO15-FIFO16-FIFO17-FIFO14-FIFO15-FIFO16-FIFO17,. . . . . The data is read in the following order: FIFO16-FIFO17. In addition, the function of writing data read from the second storage unit FIFO14-17 to the third storage unit FIFO18 through the FIFO18_WEN * (Active LOW) signal at the speed of FIFO18_WCLK is also performed by the multiplexer 33. .

As described above, according to the present invention, there is an effect that can be efficiently used in a system for multiplexing cells at high speed while minimizing data loss in an ATM-based B-ISDN network.

Claims (4)

An ATM cell receiver having a physical layer receiver for receiving a signal from a single ring subscriber access network operating at high speed, and an Asynchronous Transfer Mode (ATM) receiver for transmitting a signal to a subscriber operating at low speed. A first buffer means for receiving a signal from the physical layer receiver and storing and sorting data in a first predetermined number of octets; Cell receiving means for discriminating whether data (cell) stored in said first buffer means is data transmitted to a local station or data to be received by another node on a ring; Second buffer means for storing the data transmitted to the local station in the first predetermined number of octets; Multiplexing means for converting the data transferred from said second buffer means in said first predetermined number of octets into a byte stream of a second predetermined number of octets; And a third buffer means for receiving data from the multiplexing means and transmitting the data to the ATM receiving unit. The method of claim 1, wherein the first and second buffer means, respectively, includes a plurality of first-in-first-out buffer (FIFO) which data is stored by a predetermined bit, a cell, laid down a predetermined notification signal (FIFO13_PAE ^*, FIFO17_PAE ^A giga-class ATM receiver under a single ring structure, characterized in that it is configured to notify that there is data received using ^* ). The method of claim 1 or 2, wherein the cell receiving means includes a first read control signal FIFO13_REN * and a second read control signal FIFO13_OE when the notification signal FIFO13_PAE ^* is transmitted from the first buffer means. *) Outputs the data stored in the first buffer means at the first predetermined number of octets at a time according to the read speed control signal FIFO13_RCLK (31.25 MHz), and is transmitted to the local station according to the header of the first cell read. If the data is to be stored, it is stored in the second buffer means according to the write speed control signal FIFO_WCLK (31.25 MHz) using the first write control signal FIFO17_WEN. If the data is to be transmitted to another node on the ring, the read data is stored. Giga-class ATM receiving apparatus under a single ring structure, characterized in that the second write control signal (FIFO9_WEN) using the write speed control signal (FIFO_WCLK (31.25MHz)) to transmit to the external cell transmitter. The method of claim 3, wherein the multiplexing means reads data stored in each FIFO of the second buffer means sequentially according to a predetermined speed control signal when the notification signal FIFO17_PAE ^* is transmitted from the second buffer means. Giga-class ATM receiving apparatus under a single ring structure, characterized in that configured to store in three buffer means.