JPS63185249A - Node control system - Google Patents

Abstract

PURPOSE:To control data between divided links when a transmission medium is cut by detecting whether or not there are clocks from up and down data received from an up and a down transmission medium and the node number of a node in clock mode. CONSTITUTION:Clock detectors 11 and 13 detect whether or not there are the clocks from the up and down transmission lines 111 and 113 and input the results to a control logic 14. A node detector 12 detect the generation node of the clock and whether or not right downstream node is in return mode from the transmission line 111 and inputs the result to the control logic 14. The control logic 14 operates changeover switches SW1A, SW1B, and SW2. When the changeover switches SW1A and SW1B operate, a clock from a clock generator 15 and a marker signal indicating the its node is a clock source are outputted to the up transmission line 112 and its node enters a clock mode.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a node control method using a modified UID link method, and particularly to a highly reliable node control method.

[Conventional technology]

Conventionally, the method of connecting multiple nodes and transmitting data in opposite directions through a transmission medium divided into upstream and downstream sections inputs and outputs data to and from nodes L1 to LN, as shown in Figure 10. Data terminal unit E, ~E
It is composed of N. A clock is generated at the node L1, and the transmission line passes through each node of the upstream transmission line, turns around at the final node LN (referred to as the most upstream node), and ends at the synode L1, which becomes the downstream transmission line. At this time, each node supplies data from each data terminal unit to the uplink transmission line, and supplies data to each data terminal unit from the downlink transmission line.

Here, the transmission line connecting nodes L and
Check the situation when disconnection occurs at connection point X. 11th
As you can see in the figure, the connection point is simply disconnected, but unless self-recovery is performed within the node, the upstream and downstream transmission lines will be isolated and data transmission will be impossible. The function will stop. However, in reality, the node L has a function of short-circuiting the signals that will be input and output to the upstream and downstream transmission lines.
A link is established and data can be exchanged.

On the other hand, since nodes L3 to LN have the function of generating a clock at node L3, nodes L3 to LN have the function of generating a clock at node L3.
A link is established between LN in which data can be input/output between each data terminal unit (E, -EN) through up and down transmission lines.

However, in this case, since the conventional links are separated and links are established within each sublink, it is often impossible to input and output data between the sublinks.

[Problem that the invention seeks to solve]

The problem with the conventional technology that the present invention aims to solve is that when a transmission medium fails and is disconnected, a link is established between each of the disconnected links, but the problem between each disconnected link is data is not exchanged,
Therefore, in the worst case, it may be of no use at all.

Therefore, an object of the present invention is to provide a node control method that solves the above-mentioned drawbacks.

[Means for solving problems]

The node control method of the first aspect of the present invention detects the presence or absence of each clock from uplink and downlink data received from uplink and downlink transmission media, and detects the node number of a node in black mode or black mode. and detecting the mode of the previous node from among uplink data received from the uplink transmission medium, the presence or absence of the detected clock, the node number of the node in the clock mode, and the mode of the previous node. The self-node selects a predetermined mode from the above, sends the input data to the uplink transmission medium and outputs the data received from the downlink transmission medium, and includes a signal representing the clock generation node number. The device is configured to include the ability to generate a clock signal.

The node according to the second aspect of the present invention includes clock detection means for detecting the presence or absence of each clock from upstream and downstream data received from upstream and downstream transmission media, and detects the node number of the node in the clock mode. node number detection means; node mode detection means for detecting the mode of a previous node from among uplink data received from an uplink transmission medium; outputs of the clock detection means, the node number detection means, and the node mode detection means; a selection means for selecting a predetermined mode by the own node; a data input/output means for transmitting the input data to the transmission medium throughout the country; and data input/output means for transmitting the data received from the lower 9 transmission lines, and a clock generating means capable of generating a clock signal including a signal representing the clock signal.

〔Example〕

Next, the present invention will be described in detail with reference to drawings showing embodiments.

FIG. 1 is an explanatory diagram showing the node transition control of the present invention, FIG. 2 is a chart showing the node transition conditions of the invention, FIG. 3 is a chart showing the node mode transition status of the invention, and FIG. (a
) to (C) are explanatory diagrams showing modes of the node of the present invention, FIG. 5 is a block diagram showing the configuration of the first embodiment of the node of the present invention, and FIG. 6 is a diagram showing the configuration of the second embodiment of the node of the present invention. FIG. 7 is a block diagram showing the configuration of a third embodiment of the node of the present invention. FIG. 8 is a block diagram showing the configuration of a modified U-rick using the node of the present invention. Block Diagram,
FIG. 9 is a block diagram illustrating the operation of a modified IJ tank using a node according to the present invention when an abnormality occurs.

An overview of embodiments of the present invention will be described.

As shown in FIG. 8, one embodiment of the modified U-link system using the present invention includes upper nine transmission lines, that is, an upstream transmission line 100,
The lower transmission medium, that is, the downlink transmission line 101, and the node N1
~NH, and data terminal units E1 to EN that input and output data corresponding to the respective nodes, and the one-multiple transmission line 100 and the downlink transmission line 101 connect to the nodes N1 to N'
Each N is connected in a ring. In such a case, any one node, for example, the clock generator 10 of node N1
2 is activated and supplies a clock signal to the upstream transmission line 100. Signals on the uplink transmission line that are input at the same time are folded back as they are and output to the downlink transmission line.

Further, data output from the data terminal unit is output from each corresponding node to the uplink transmission line, and data outputted from the downlink transmission line is outputted from each node to the corresponding data terminal unit. Next, referring to FIG. 9, the situation when the transmission line is cut will be explained. For example, if the transmission line between nodes N3 and N4 is disconnected at the connection point X1, a clock is generated from node N4 and node N1
is a normal repeater, and the signal from the uplink transmission line output at p-node N3 is directly connected to the downlink transmission line.
[J IJ tank starts operating in the same form.

In order to perform such operations, each node detects the situation, and depending on the result, the mode of the node changes to generate a clock.

Next, the operation of the mode of the node according to the present invention will be explained.

First, the three glaze modes of the node will be explained.

Looking at Figures 4(a) to (C), the common operations required are:
The two steps are to provide input data to an upstream transmission medium, ie, an upstream transmission line, and to provide output data from a downstream transmission medium, ie, a downstream transmission line. The first mode shown in FIG. 4(a) is called a repeater mode, and is the upstream transmission medium on the clock source side (for example, connected to the node NN-1 side with respect to the node NN shown in FIG. 8). The data received on the upstream transmission line (referred to as upstream data from the downstream node) is output as is to the upstream node, and the data received on the downlink transmission line (referred to as downlink data from the upstream node) is output as is to the upstream node. It is output to a downstream transmission medium, that is, a downstream transmission line (sent to a downstream node) on the clock source side (for example, connected to the node NN-1 side with respect to node NN shown in FIG. 8). The second mode shown in FIG. 4(b) is called a return mode, in which upstream data from the downstream node is sent as is to the upstream node, and is also sent to the downstream node as downstream data. Although the downstream data from the node is detected, it is not taken in and is interrupted at this node. Node 30 shown in FIG. 4(C) is in clock mode, in which it generates a clock from its own node, does not send it as upstream data to the upstream node, and returns upstream data from the downstream node to the downstream node. It is sent as data to downstream nodes.

Furthermore, the contents of detection of the link status that each node has for transition between these modes will be explained. The first detection content is to detect the presence or absence of a clock on the uplink transmission line, and the second detection content is to detect the presence or absence of a clock on the downlink transmission line. The third detection content is the clock generation source (
The fourth detection content is to detect whether the immediately downstream node (that is, the previous node) is in loopback mode.

Next, we will show the main conditions for node transition for recovery such as transmission line disconnection. Firstly, when there is no clock on the upstream transmission line, the detected node is in clock mode.Secondly, in repeater mode, when there is no clock on the downstream transmission line, the node is in loopback mode.Thirdly, the node is in loopback mode. In the third case, if there is a clock on the downlink transmission line, the own node becomes a repeater node.Fourth, in the third case, when the immediately downstream node is in return mode, the own node becomes the clock mode.Fifth, the clock mode Sixth, in the fifth case, if the node directly downstream is in loopback mode, the second node remains in clock mode; seventh, when the clock mode is When there is a clock source on the upstream and downstream transmission lines, it is always in Peter mode. Eighth, in the seventh case, when the immediately downstream node is in loopback mode, the clock is on the upstream transmission line. The condition for node transition is to remain in the mode. FIG. 3 summarizes these node transition conditions in more detail, and FIG. 1 shows the details of node transition control under these conditions. In addition, the symbols IA and I in Figures 1 and 2
The symbols B... indicate control conditions. Further, FIG. 3 shows the modes before and after the transition in this case, corresponding to each condition. The present invention can be implemented by the method described above.

Next, an example of these operations will be explained with reference to FIGS. 8 and 9.

In FIG. 8, if the upstream and downstream transmission lines connecting node N3 and node N4 are disconnected, first the clock coming out from N1 is transmitted at node N, ・N, and upstream clock. Even if a clock is applied to the transmission line, no clock is detected on the downstream transmission line. Also, node N4~
In the NN, no clock is detected on the upstream and downstream transmission lines. Furthermore, the clock input from the upstream transmission line is not detected at the node N1. At this time, the nodes N and N3 enter the return mode according to the IC transition conditions shown in FIG. 2, but since the operating times of the nodes are generally different, the node that transitions earlier comes to dominate the node that transitions later.

In this case, when node N becomes loopback mode, node N
, remains in the repeater mode under the IF transition conditions of FIG. 2 because the clock is detected on the upstream and downstream transmission lines. However, when node N enters loopback mode, node N1 has a clock on its upstream transmission line but does not have a clock on its downstream transmission line, and node N immediately downstream is in loopback mode. Under the transition condition of IB in FIG. 2, node N3 enters the return mode. Next, node N2 has a clock on the upstream and downstream transmission lines, and the node N immediately downstream is in clock mode, so under the transition condition of 2F in FIG. 2, node N! Becomes a stiff Peter mode.

On the other hand, in the nodes N4 to NN, since there is no clock on the upstream and downstream transmission lines, the node with the fastest transition operation under the transition condition of IA in FIG. 2 becomes the clock mode. At this time, all downstream nodes from the node that has entered the clock mode, such as the node NN, remain in the repeater mode because there are clocks on the upstream and downstream transmission lines. Next, among the nodes upstream of the node that has entered the clock mode, the node that has completed the transition operation becomes the clock mode. In this way, the action extends downstream,
Finally, node N4 enters clock mode. Therefore, a clock mode node sandwiched between repeater mode nodes has a clock on the upstream and downstream transmission lines, and the node immediately downstream is a repeater, so other nodes can be detected. , node N, and the second
According to the transition condition of 3F in the figure, everything becomes repeater mode.

Therefore, node N4 is in clock mode, node N3
is in loopback mode, and all other nodes are in repeater mode to complete the link as shown in FIG.

Next, an embodiment of the present invention will be described, focusing on its configuration and operation.

As shown in FIG. 8, the nodes N1 to NN of the modified U-link using the nodes of the present invention are connected to the upstream transmission media consisting of lines such as coaxial cables, that is, transmission Hi 100 and T-
1) Connected by a transmission rod, that is, a downstream transmission door 101, data is supplied from the data terminal units D1 to DN to the upstream transmission line 100 through nodes N1 to NN, and data from the downstream transmission line 101 is supplied to the terminal units D1 to DN. D.N.
The signals are supplied to the corresponding nodes N□ to NN through the respective nodes. Each node is constructed so as to be able to make mode transitions as shown in FIG. 3 during the link, and a first embodiment thereof is shown in FIG.

Next, the configuration and operation of the first embodiment of the node of the present invention will be explained.

As shown in Fig. 5, the signal of the upstream transmission medium is the upstream transmission line 11.
1 to the node IA and output to the uplink transmission line 112, and the signal of the downlink transmission medium is inputted from the downlink transmission line 113 and output to the downlink transmission line 114, and the transmission signal is configured with a coaxial cable or a two-wire system. . Also, data terminal unit 2
data from the upstream transmission line 11 through the data inserter 17
2 and the data output from the down transmission line 113 is also supplied to the data terminal unit 2.

Next, the node IA includes clock detectors 11 and 13, a node detector 12, a control logic 14, and a clock generator 1.
5, a mode inserter 16, a data inserter 17, and changeover switches 5WIA-8WIB/8W2.

First, the clock detectors 11 and 13 detect the presence or absence of clocks on the upstream and downstream transmission lines 111 and 113, respectively, and input the results to the control logic 14. Occurrence node (
In other words, the detection of the clock source node) and the detection of the immediately downstream node (
It is detected whether the previous node) is in loopback mode or other mode, and the result is input to the control logic 14.

Furthermore, the mode inserter 16 inserts a recognition signal into the transmission data frame when the own node is in the loopback mode, and the data inserter 17 inserts the data from the data terminal unit 2 into the uplink transmission line. It is inserted into the data frame.

On the other hand, the operation of the control logic is controlled by the selector switch 5WIA・8.
In addition to activating WIB and SW2 (turning them ON), when the selector switch is not activated, it is in repeat mode. Next, selector switch 5WI
When A and 5WIB operate (turn ON), the clock output from the clock generator 15 and the indicator signal indicating that the own node is the clock source are switched to the changeover switch 5W.
It is output to the up transmission line 112 through the IA, and the input of the up transmission line 111 is output to the down transmission line 114 through the changeover switch 8WIB, and the mode of the own node becomes the clock mode. Further, when the changeover switch SW2 is activated and is in the ON state, the output of the uplink transmission line 112 is simultaneously output to the downlink transmission line 114 through the changeover switch SW2, and the mode of the own node is not in the loopback mode. An indicator signal indicating that the transmission data is transmitted is also outputted through the mode inserter 16 into the frame of transmission data on the uplink transmission line 112. Further, here, only the indicator signal indicating that the mode inserter is in the loopback mode is outputted into the frame of the transmission data on the uplink transmission line, but the indicator signal may be used by identifying three modes. The operation of the control logic 14 based on the operations of the nodes as described above is determined by the presence or absence of clocks on the upstream and downstream transmission lines in FIG. 3 and mode transitions based on incidental conditions.

Next, the configuration and operation of a second embodiment of the node of the present invention will be explained.

Looking at Figure 6, the signal of the upstream transmission medium is the upstream transmission line 1.
21 to the node IB, it passes through the energy converter 18 into an electrical signal, is internally processed and passes through the electro-optic converter 19 and becomes an optical signal again), and is output to the upstream transmission line 122, and the transmission medium, that is, the transmission line is It is composed of optical fibers, etc., and the signal is an optical signal. Similarly, the signal of the downlink transmission medium is inputted to the node IB from the downlink transmission line 123, passed through the opto-electric converter 20 to become an electrical signal, processed internally, passed through the opto-electro converter 21 and turned into an optical signal again, and then transmitted down. is output on line 124. Node IB includes clock detectors 11 and 13, node detector 12, and control logic 14.
, clock generator 15, mode inserter 16, data inserter 17, and selector switch 5WIA-8WIB-8
W2, optical converter 18, 20 and electro-optical converter 19,
21. The photoelectric converter 18.2 mentioned above
The construction and operation of the second embodiment of the node of the present invention is similar to that of the first embodiment, except for the construction and operation of the electro-optical converters 19 and 21.

Since the second embodiment of the node of the present invention uses an optical fiber as the transmission medium, the transmission medium has extremely strong resistance to electromagnetic interference and can be used in harsh environments.

Next, the configuration and overall operation of the third embodiment of the node of the present invention will be explained.

Looking at FIG. 7, the signal on the upstream transmission medium is transmitted through the upstream transmission 912.
1 to the node IC, is converted into an electrical signal through the optical cutter 22 and the opto-electrical converter 18, is processed inside the node IC, and is converted into an optical signal again through the electrical converter 19,
The signal is output to the upstream transmission line 122 through the optical cutter 22.

The transmission medium is composed of an optical fiber or the like, and the signal is an optical signal.The optical disconnection container 22 operates the link at the expense of data input/output of the node when a node IC malfunctions. In order to continue, the switching node IC is excluded by the activation signal 131, and this is generally done at the same time as the switching of the downlink transmission medium. Similar to the uplink transmission medium, the signal of the downlink transmission medium is transmitted through the upper transmission line 123.
The electrical signal is input to the node IC through the optical converter 23 and the opto-electrical converter 20, is processed inside the node IC, passes through the optical converter 21 to the optical converter 23, and is converted into an electrical signal through the upstream transmission line 124. is output to. The light-cut container 23 is a node IC
When an abnormality occurs in the operation of the node, the operation signal 1 is activated in order to continue the operation of the link at the expense of the data input/output of that node.
32 to exclude the node IC. Except for the structure and operation of the light cutting containers 22 and 23, the structure and operation of the third embodiment of the node of the present invention are similar to those of the second embodiment. The third embodiment of the node of the present invention uses an optical fiber as a transmission medium and is equipped with an optical cutter that can be operated from the outside, so that even if a node malfunctions, the node can be excluded. can be used to form a link.

〔Effect of the invention〕

As explained in detail above, the modified node control method of the present invention [J IJN-type node control method is not a foolproof method in that a link as a U-link method can be established even if a transmission medium fails and is disconnected. By using optical fiber as the transmission medium, it is possible to increase the resistance to magnetic interference, and even if a node becomes defective, it can be excluded and the link can be established, resulting in highly reliable data transmission. This has the advantage that a link method can also be provided.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the node transition control of the present invention, and FIG.
The figure is a diagram showing the node transition conditions of the present invention, Figure 3 is a diagram showing the mode transition status of the node of the present invention, and Figure 4 (
a) to (C) are explanatory diagrams showing modes of the node of the present invention,
FIG. 5 is a block diagram showing the configuration of a first embodiment of the node of the present invention, FIG. 6 is a block diagram showing the configuration of the second embodiment of the node of the present invention, and FIG. 7 is a block diagram showing the configuration of the node of the present invention. FIG. 8 is a block diagram showing an example of the structure of the third embodiment of the invention, FIG. A block diagram illustrating the operation in the event of a link abnormality, FIG. 10 is a block diagram showing an example of a conventional node. [J Block diagram illustrating the operation when an abnormality occurs. 1...Node, 2...Data terminal unit, 11.13...Black detector, 12.
... Node detector, 14 ... Control logic, 15 ... Clock generator, 16 ...
-Mode inserter, 17...Data inserter. /F Bud / Flash / 12-: Repeater mode F: Evil 2 Exposure mode C: RiU・-Tsuku mode Kaya 2 Sen'Rota' J Ire 4 vri (a) Number Ishi 4 rY ■ (15-) Kaya 4 Ho'J (C)

Claims (2)

[Claims] (1) Detecting the presence or absence of each clock from the upstream and downstream data received from the upstream and downstream transmission media, detecting the node number of the node in clock mode, and detecting the presence or absence of each clock from the upstream and downstream data received from the upstream and downstream transmission media, and The mode of the previous node is detected from the data, and the own node determines a predetermined mode based on the presence or absence of the detected clock, the node number of the node in the clock mode, and the mode of the previous node. a node that is capable of selecting data, transmitting input data to an upstream transmission medium and outputting data received from a downstream transmission medium, and generating a clock signal including a signal representing a clock generation node number. control method. (2) clock detection means for detecting the presence or absence of each clock from uplink and downlink data received from uplink and downlink transmission media; node number detection means for detecting the node number of a node in clock mode; and uplink transmission node mode detection means for detecting the mode of the preceding node from among the upstream data received from the medium; the own node is predetermined by the outputs of the clock detection means, the node number detection means, and the node mode detection means; A selection means for selecting a mode, a data input/output means for sending input data to an uplink transmission medium and outputting data received from a downlink transmission medium, and a clock capable of generating a clock signal including a signal representing a generation node number. A node used in a node control method comprising a generating means.