KR960001049B1 - Error recovery unit for module communication of dual ring - Google Patents

Abstract

a multiplexer for multiplexing data; a buffer for storing data information multiplexed by the multiplexer, inputting an error recovering signal, and outputting an output data; an error recovering unit for inputting a state signal of adjacent module, a ring state signal, a transmission signal, an output signal of the buffer, sensing an error by applying a transmission clock from outside, outputting a loop back signal from the multiplexer, and recovering the error; a garbage erasing unit for erasing garbage of data transmitted; and a loop back module identification number tagging unit for inputting a transmission signal from which garbage is erased, and outputting a tagging data to the multiplexer.

Description

Error recovery device for module communication with double weight structure

1 is a schematic block diagram of an error recovery apparatus for module communication under a double ring structure of the present invention.

2 is a view showing an embodiment of an error recovery circuit according to the present invention.

Figure 3 is a module connection configuration by the error recovery under the double ring structure according to the present invention.

* Explanation of symbols for main parts of the drawings

1: multiple circuit 2: error recovery circuit

3: garbage elimination circuit 4 buffer

5: loopback module identification number tagging circuit 6: the coder

7: cell boundary control circuit

The present invention relates to an error recovery apparatus for a module communication of a dual ring structure conforming to the user-network interface standard of the broadband general-purpose general network recommended by CCITT, an international standard organization.

Conventional double-ring structure communication is used for data transmission before one ring in case of errors that may occur in modules and links, and the entire remaining one ring in the opposite direction transmits the same data as a spare ring to maintain normal status. There is a problem in that the data transfer amount is equivalent to using only one ring.

The present invention devised to solve the above-mentioned problems in the prior art uses two rings for different data transmissions in a steady state, thereby using two rings for different data transmissions. In case of failure in module and link, the error is recovered by using the remaining normal ring instead of using only the part where error occurs. It is an object of the present invention to provide an error recovery device for module communication of a dual ring structure that allows the north of the link to be lost and erases garbage on the ring in connection with the error recovery.

In order to achieve the above object, the present invention provides a multiplexing means for multiplexing data from a physical path by means of a loop back path and a transmission medium in a module, storing multiplexed data information from the multiplexed fisheries, and recovering an error recovery signal. The multiplexing means after detecting an error by receiving a buffer, an output signal of a neighboring module, a directional ring status signal, and a transmission signal, receiving an output signal of the buffer, and applying a transmission clock from the outside. Error recovery means for performing recovery by outputting the loopback signal and outputting the bypass signal to the outside; And a gabbage erased transmission signal connected to the garbage elimination means. Provided with a loop-back module identification number tagging means for tagging the output data group to the multiplexing means.

For module-to-module communication, it operates in 56-octet module communication cell units defined by 4-octet headers and 52-octet payloads, and internally processes 32-bit units internally. It is performed under the ATM layer of the protocol reference model of the network user-network interface. Basically, it consists of a transmitter and a receiver, each connected to two physical transmission media. The transmission directions of the two transmission media are opposite to each other and form a ring.

The error recovery apparatus according to the present invention is located between a transceiver and a physical transmission medium for the module communication function, and when an error occurs, disconnects the connection between the transmission medium and the transmission device and loops back or bypasses the transmission and reception unit. Bypass connection maintains the connection between the communication modules on the ring and eliminates garbage generated with loopback. Conversely, it can also be used to reconnect a module or link removed from the ring due to an error. Only one for the error recovery presented in the present invention. Or only two cell losses are guaranteed.

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

1 is an overall configuration diagram according to the present invention, Figure 2 is a detailed view of the error recovery circuit according to the present invention, Figure 3 is a module connection configuration diagram by the error recovery under a double ring structure for explaining the present invention in detail, Where 1 is the multiplexing circuit, 2 is the error return circuit, and 3 is the garbage elimination circuit. 4 denotes a buffer, 5 denotes a loopback module identification number tagging circuit, 6 denotes a decoder, and 7 denotes a cell boundary control circuit.

As shown in the figure, the error recovery apparatus of the present invention includes an error recovery circuit 2 including a multiplexing circuit 1, a decoder 6, and a cell boundary control circuit 7, an open circuit cancellation circuit 3, and a buffer. (4), the loopback module identification number tagging circuit (5), a detailed description of the configuration is as follows.

When the loopback signal is enabled by the multiplexing circuit 1, loopback data [32: 0] is transmitted from the transmitter of the module communication function instead of the Lang data [32: 0] from the physical medium connection (not shown). It transfers to the buffer 4 which is accessed by the receiving unit of the communication function, and conversely, ring data [32: 0] is transferred to the buffer 4 when disabled.

To this end, the error recovery circuit 2 determines whether to perform loopback based on the adjacent module status signal of the physical medium connection unit. The error recovery circuit (2) receiving the neighbor module status signal informing the error of the neighbor module or the link is a module communication function receiver to ensure cell-based access for 56 octets of module communication function to the buffer (4). Wait until the access of the module communication cell being accessed from the buffer 4 is completed by using the output signal indicating the current access state of the signal, and enable the loopback signal to the multiplexing circuit 1 at the moment of completion of access. Here, means a transmission device or a physical transmission medium connected to the transmission device of the module communication for transmitting data to the magnetic module on the adjacent module or a specific ring linked, the error recovery circuit (2) to the multiplexing circuit (1) To generate an input signal suitable for the input of input data into the buffer 4.

The error recovery circuit 2 uses a decoder 6 for the adjacent module status signal Hin echo ring status signal and a loopback signal, a bypass signal, and an input by using an output signal or a transmission signal to ensure cell-level access for module communication of 56 octets. The cell boundary control circuit 7 is configured to generate a signal.

The error recovery operation described above will be described with reference to FIG.

3 is a schematic diagram of forming five rings of five modules of Modules 1 to 5 in a clockwise direction, in which (A) is a double ring configuration during normal operation, and (B) is a loopback for module error recovery. Configuration diagram (C) is a loopback configuration diagram for link failure recovery.

(A) shows the configuration of the connection between modules by double ring during normal operation without error. If (B) shows a certain module (for example, module 3) is down, If the operation is not possible due to the failure, the module 2 and the module 4 having the module 3 as the adjacent module recognize the error of the module 3 by the adjacent module status signal in their error recovery circuit 2, respectively, and the multiplexing circuit 1 A loopback signal is generated to change the double ring into a single unidirectional ring. If, as in (C), it is impossible to transmit information between modules connected to that link due to an error in a particular link (e.g., a transmission link from module 3 to module 2), module 2 with module 3 as an adjacent module (B) The loopback is performed as shown in Fig. 6), but module 4 having module 3 as an adjacent module performs normal operation because the transmission link from module 3 is in good condition.

However, a problem arises in that module 4 cannot transmit to a desired module except for information destined for module 3 of module 3. In order to solve this problem, the module 3 recognizes an error in the transmission link between the module 3 and the module 2 by the echo ring state signal in the error recovery circuit 2 and determines the state of the reverse ring. Send a bypass signal to the transmitter to bypass the receive link in module 4 direction. Also in this case, as in the case of the loop back, the error recovery circuit 2 having received the echo ring state signal is provided with the module communication function transmitter of the module 3 for ensuring 56 octets of cell unit transmission for module communication by the transmitter of the module 4. Wait until the transmission of the module communication cell being transmitted is completed by using the transmission path transmitted to the error recovery circuit 2 to inform the current transmission state, and the module 3 enables the bypass signal to the transmitter at the moment of completion of transmission. .

On the contrary, when the module or link removed from the double ring due to an error occurs is connected to the ring again, when the error recovery circuit 2 receives an adjacent module status signal or an echo ring status signal indicating a good state of the module or link. The output signal to the buffer 4 refers to the transmission signal from the module communication transmitter to disable the loopback signal or the bypass signal at the moment of completing the output or transmission of the module communication cell in progress.

In the case of performing the above-mentioned error recovery, in particular, when a particular module is removed from the ring due to an error as shown in (B), information destined for the module is floated on the ring. In order to erase such garbage, the module communication number is stored in 56 octet unit using its loopback identification number tagging circuit (5) for all loopback data [32: 0] generated from the transmitter of the module communication function. After loopback by writing bits 31 to 28 of loopback data [32: 0] corresponding to the first four octaves of the loop, the module identification number is transmitted by loopback data [32: 0] according to the transmission signal tagged with its own module identification number. The 56 octets of module communication cells are erased by the garbage elimination circuit 3.

Cells tagged with other module identification numbers are transparently transmitted to the loopback module identification number tagging number (5). If the loopback signal is enabled from the error recovery circuit 2, the identification number of the module loopbacked to the loopback data [32: 0] by the loopback module number tagging circuit 5 is 56 octets of module communication cell units. The tagging data [32: 0] tagged by the [0100] tag is input to the buffer 4 through the multiplexing circuit 1, and this information is transmitted through the ring data [32: 0] in the module where loopback has not occurred. It is input to the buffer 4 through the multiplexing circuit 1.

Referring to the case of (B), the loopback module identification number tagging circuit 5 of module 2 and module 4 tags its own module identification signal to perform loopback by the loopback signal of the error recovery circuit 2. The cells destined for module 3 are then delivered to the gate clearing circuit 3 of module 2 or module 4 while tagging the module identification number of module 2 or module 4 and these cells are looped through the ring. The cells are erased because they do not find their destination.

In the case of (C), since the cells of the loopbacked cells tagged as module 2 destined for module 3 are normally delivered to module 3 and received, they do not return to the garbage elimination circuit 3 of module 2 again. Do not.

As described above, the present invention provides a module in a high-speed communication function under a unidirectional dual ring structure between unit modules constituting a large capacity subscriber access node located at a user-network interface of a broadband integrated information network or between subscriber access nodes distributed within a short distance. If the ring does not operate normally due to node or link error, this can be solved by loopback or bypass function.

Claims (2)

Multiplexing means (1) for multiplexing data from the physical path by the loop back path and the transmission medium in the module, and storing the multiplexed data information from the multiplexing means (1) and receiving the error recovery signal and outputting the output data. After receiving the output buffer 4, the adjacent module status signal, the echo ring status signal, and the transmission signal, the output signal of the buffer 4 is input, and an external-transmission clock is applied to detect an error occurrence. Error recovery means (2) for outputting the loopback signal to the multiplexing means (1) and outputting the bypass signal to the external channel to perform recovery, identifying the garbage among the data received by receiving the module identification number and receiving the system clock and loopback data. And a plurality of garbage eliminating means (3) for erasing and receiving the transmission signal connected to the garbage eliminating means (3) to the multiplexing means (1). And a loopback module identification number tagging means (5) for outputting tagging data. The method of claim 1, wherein the error recovery means (2) comprises; Decoder 6 for identifying the type of error generated by receiving the adjacent module status signal and the echo ring status signal, inputs the output value of the decoder 6 and receives the transmission clock from the outside, and receives the loopback signal, the input signal, and the detour. And a cell economic control means (7) for generating a recovery signal comprising the signal.