JPS63136750A - Communication system - Google Patents

Abstract

PURPOSE:To decrease the delay in a message attended with relay by managing a network comprising lots of time division numtiplexers while it is divided into plural small scale sub-networks and connecting a network management equipment and a primary station of each sub network by means of a user line and an expanded network management information bit. CONSTITUTION:Plural sub network 20-23 comprising a few time division multiplexers 2a, 2b, 2c are connected mutually by high speed digital lines 3a-3d to constitute a large scale of network. Moreover, one set of the network manage ment equipment 1 is connected to a primary station 2a of the master sub net work 20 to manage the entire network and a communication message between the network management equipment 1 and the primary station 2a of the other sub networks 21-23 is sent through a user line from the network management equipment 1 to the time division multiplexer accommodating high speed digital lines connected directly to a destination sub network and the data is transferred from the primary station of the sub network from the time division multiplexer corresponding to an exit by using an expanded network management information bit provided to a control region on the high speed digital line.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a communication system that transmits information such as data, audio, and images by time division multiplexing.

[Conventional technology]

Figure 3 shows a conventional communication system using a time division multiplexer.
FIG. In the figure, 1 is a network management device, 2a
, 2bi time division multiplexing device; 3 is a high-speed digital line that connects all the time division multiplexing devices 2a and 2b; 4 is a terminal accommodated in each of the time division multiplexing devices 2a and 2b; The network management device 1 is connected to one of the time division multiplexing devices 2a, and is also connected to another time division multiplexing device 2b via this time division multiplexing device 2a. . Hereinafter, the time division multiplexing device 2 a k to which this network management device 1 is connected, the primary station to which the network management device 1 is connected n
Time division multiplexer 2b that is not installed? It is called a secondary station, and unless otherwise specified, it is called a time division multiplexer 2. Communication paths are established between the terminals 4 connected to each time division multiplexer 2 and the terminals 4 connected to other time division multiplexers 2 using high-speed digital lines 6 and time division multiplexing. Provides all
The network management device 1 monitors and controls all the time division multiplexing devices 2 in the system.0 Figure 4 is a frame configuration diagram showing the transmission frame format on the high-speed digital line 6. In Fig. 4, 5 is a frame, 6 is a control area, 7 is a data area, 8 is a network management information bit, and 9 is terminal data? Pit group to carry?
60 Next, the operation will be explained. A bit string is transmitted at a constant speed on the high-speed digital line 6, and a frame 5 is composed of a constant number of consecutive bits. A frame 5 of a time division multiplexer 2 is divided into a control area 6 and a data area 7 for use.

In the data area 7, data from a plurality of terminals 4 is transmitted by time division multiplexing. In FIG. 2, a plurality of bit groups 9 are taken up in the data area 7, each bit group 9 carrying one terminal 4 data. In the control area 6, information for ensuring complete synchronization of the frame 5, network management information, etc. are transmitted.

Network management information is transmitted by network management information bit 8.Network management information is network management information that is used to monitor, control, and test the time division multiplexing device 2 that makes up the entire communication system, because all the tests are performed by one network management device 1. This is information transmitted and received between the management device 1 and each time division multiplexing device 2.

It is necessary for the network management device 1 to communicate with all the time division multiplexing devices 2 in the communication system, but as described above, the network management device 1 itself only communicates with one time division multiplexing device, that is, the primary station 2a. A direct connection is a scam.

FIG. 5 is a configuration diagram showing the configuration of a network for transferring network management information, and each time division multiplexing device 2 connected by a high-speed digital line 6 is connected to the control area 6 of the high-speed digital line 6. A communication path called a service channel 12 is formed by the network management information bit 8 provided.
This service channel 12 constitutes the service line network shown in FIG. 5. This service line network is a network for transferring management information between the network management device 1 and each time division multiplexing device 2. It is. Communication between the network management device 1 and the secondary station 2b is performed by sending and receiving messages containing management information. In the service line network shown in FIG. 3, communication between the network management device 1 and the secondary stations 2b, which are not directly connected by a line, includes the primary stations 2a and 2, which are intermediate stations.
This is done by the next station 2b relaying messages addressed to other than its own station. This relay rr, primary station 2a and secondary station 2
This is done by temporarily storing the message in the memory, analyzing the destination address assigned to the memory, and transferring the message to the next primary station 2a or secondary station 2b.

[Problem that the invention seeks to solve]

Since the conventional communication system is configured as described above, when the number of time division multiplexers 2 in the system increases, a large number of secondary stations 2b are added from the terminal secondary station 2b to the primary station 2a.
9. It takes time for a fault detected at the secondary station 2b to reach the network management device 1, and the network management device 1 Are all the messages communicated with the primary station 2a and the lines connecting the primary station 2a and the network management device 1? These factors suppress the transfer capacity of the service line, and as a result, when the system is initialized, the network management device 1 transfers all control information to the primary station 2a and all secondary stations 2b in the system. There were some problems, such as the long time required.

This invention was made to solve all of the above-mentioned problems, and it is possible to manage a network consisting of a large number of time division multiplexing devices by dividing it into multiple small-scale subnetworks, and to transfer control information. The purpose is to obtain a complete communication system that reduces the time required.

[Means to solve all problems]

Is the communication system according to the present invention a small-scale network composed of a small number of time division multiplexers? A large-scale network is constructed by interconnecting multiple subnetworks with all high-speed digital lines, and managing multiple subnetworks with one network management device. is connected to the primary station of one subnetwork to manage the entire network, and for communication messages between the primary station of other subnetworks and the network management device, it is possible to use a high-speed connection directly from the network management device to the destination subnetwork. A user line is used to transmit information up to a time division multiplexing device that accommodates a digital line, and the area from the time division multiplexing device corresponding to the above-mentioned exit to the primary station of the subnetwork is provided in a control area on the high-speed digital line. 0 [Operation] The communication system according to the present invention divides and manages a large-scale network made up of a large number of time division multiplexing devices into a plurality of sub-networks. The primary station of a subnetwork only needs to relay messages addressed to the time division multiplexing device within its own subnetwork, reducing the load on the primary station. In between, the extended network management information bits of the user line and control area are provided with a fully integrated communication path, allowing the network management device to communicate with multiple primary stations at the same time, and during the initial network startup. The time required to transfer control information to all time division multiplexers is shortened, and the number of relay stations is reduced in transferring messages from secondary stations to primary stations in each subnetwork, reducing message delays. is also shortened.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 1 is a network management device, and 2a and 2b are time division multiplexing devices for a primary station and a secondary station. It is something. 20, 21, 22, and 23 are formed by several time division multiplexing devices 2, and the network management device 1 is connected to the primary station 2 of this subnetwork 20.
connected to a. Hereinafter, the subnetwork 20 to which this network management device 1 is connected will be referred to as a parent subnetwork, and other subnetworks 21, 22, and 23t-child subnetworks. Furthermore, at the secondary station serving as the exit of the 2cU parent subnetwork 20, 5a@5b*3c, 3d are high-speed digital lines that interconnect all of the subnetworks 20, 21°, . . . .

Furthermore, FIG. 2 is a frame configuration diagram showing the transmission frame format completely transmitted on the high-speed digital line of such a communication system, and is 5at! High speed digital line 3
The transmission frame structure on a, 5bU same <3'b, 5d [same < 3d is shown, and shows the transmission frame structure of the primary station 2a of the 5fH parent subnetwork 20 and the secondary station 2ck serving as its exit.
Transmission frame structure on high-speed digital line? It shows.

In FIG. 2, 6 to 9 are a control area, data area, network management information bits, and a bit group carrying terminal data that are equivalent to those in FIG. 4, and 60 is an extended network management information bit, and 61 is the network management information of the child subnetwork 21,
62 is network management information of the child subnetwork 22.

Next, the operation will be explained. As shown in FIG. 1, the network includes a plurality of subnetworks 20, 21 . . . each formed by a relatively small number of time division multiplexers 2. ...
It is constructed by interconnecting each other with high-speed digital lines 3a, 6b, . . . , and each subnetwork 20, 21 . There is a primary station 2a in each of...
Same subnetwork 20.21. The other time division multiplexing device within... becomes the secondary station 2b. Therefore, although there are a plurality of primary stations 2a in the network, only one network management device 11-1+ manages the entire network.
, there are multiple subnetworks 20 in the network management device 1.
, 21° . . . is connected to one primary station 2a.

Here, each subnetwork 20° 21 is connected to the network management device 1.
, . . . is equivalent to being connected to the primary station 2a of , . . . by an individual interface line. That is, it is a device that can be connected to the network management device 1 through multiple lines, and is connected to each subnetwork 20, 21 . The primary stations 2a of . . . ...0
When viewed from the primary station 2a, the network management device 1 appears to be the same as the conventional single-line network management device 1, and therefore, the primary station 10 of each subnetwork 20, 21°, etc. is connected to a plurality of subnetworks 20°. There is no need to be aware that the network management device 1 is connected to the primary station 2a of the parent subnetwork 20. 1
Each primary station 2a of child subnetworks 21, 22゜26
Unlike the conventional connection, information for network management with each of these child subnetworks 21, 22, and 23 is partially transferred through the user line.

Furthermore, a child subnetwork 21 that exits from the network management device 1
．． The interface line to each primary station 2a of 22.23 is once connected as a data terminal in the parent subnetwork 2001 primary station 2a, and these child subnetworks 2
1.22.26 management information within the subnetwork 20 is transmitted through the data area 7 as terminal data.

The frame indicated by 5f in FIG.
The frame structure on the high-speed digital line between the primary station 2a and the secondary station 2C in 0 is shown, and on these 7 frames, management information '51 addressed to the child subnetwork 21 and management information '51 addressed to the child subnetwork 22 are transmitted. management information 62 in the data area 7.

A secondary station 2c serving as an outlet of the parent subnetwork 20 is connected to a primary station 2a of the child subnetwork 21 via a high-speed digital line 3a. The primary station 2ai of the child subnetwork 21 transmits management information 61 addressed to its own subnetwork using the extended network management information bit 30 taken in the control area 6 on the high-speed digital line 6a. The frame structure on the high-speed digital line '5a is as shown in 5a in FIG.
transfers the management information 61 addressed to the primary station 2a of the child subnetwork 21 stored in the data area 7 of the frame 5f to the extended network management information bit 60 of the frame 5a on the high-speed digital line 3a. Child subnetwork 2101st station 2
a transmits and receives network management information to and from the network management device 1 using this extended network management information bit 60. In this way, the primary station 2a of the child subnetwork 21, 22, 23 always communicates with the network management device 1 using the extended network management information bit 60 on the high-speed digital lines 3a to 6d. By doing this, the data area 7 of the time division multiplexing device 2 is originally an area for carrying terminal data, but the network management device 1 manages the allocation of this area, and after initializing the system, By the network management device 1 distributing information regarding the allocation of the data area 7, each time division multiplexing device 2
You can find out how it is used.

In such a system, if the primary station 2a of the child subnetworks 21, 22, 23 transfers information with the network management device 1 in the data area 7, the primary station 2a of the child subnetworks 21, 22, 23 When initializing the station 2au, the child subnetwork 21,
It is determined that the primary station 2ai of 22.26 always communicates with the network management device 1 using the extended network management information bit 50 of the control area 6. Although the network management device 1 simultaneously communicates with a plurality of primary stations 2a, it can communicate with only one primary station 2a at the same time using the extended network management information pit 60. For this purpose, when information addressed to multiple child subnetworks 21, 22, 23 is transmitted to the network management device 1 using the data area 7, and transmitted to the primary station 2a of a certain child subnetwork 21, 22, 23. , the primary station 2a and high-speed digital lines 3a, 3b,
Extended network management information bit 60 from the data area 7 to the control area 6 in the time division multiplexing device 2 directly connected by...
Transfer to.

Further, information between the primary station 2a of the child subnetwork 21 and the network management device 1 on the high-speed digital line 6a is carried by the extended network management information bit 60, but the information between the primary station 2a of the child subnetwork 22 and the network Information to and from the management device 1 is conveyed in the data area 7. The management information LO 2 of the child subnetwork 22 is transferred from the data area 7 to the extended network management information bit 60 of the frame 5b at the secondary station 2b serving as the exit to the child subnetwork 22 of the child subnetwork 21. As a result, the primary station 2af of the child subnetwork 22
4 High-speed digital line 6b extended network management information bit 60
This enables communication with the network management device 1.

Next, the startup process of the communication system will be explained. Parent subnetwork 2 directly connected to network management device 1 for the first time
0 rises, and information regarding the use of the data area 7 is distributed to each time division multiplexer 2 in the parent subnetwork 20. Based on this information, it is known which part of the data area 7 of the secondary station 2cU serving as the exit should be converted into the extended network management information bit 30, and the conversion is performed. As a result, communication becomes possible between the primary station 2a of the child sub-network 21 and the network management device 1, and from the network management device 1 to the child sub-network 2.
The network management information 61 is distributed to each time division multiplexing device 2 in the time division multiplexing device 1, and the child subnetwork 21 is established. By starting up the child sub-network 21, the child sub-network 22
The communication path between the primary station 2a and the network management device 1 is secured, and thereby the network management information 32 of the child subnetwork 22
is distributed, and the child sub-network 22 is thereby established. As described above, the subnetworks 20, 21 . For example, after starting up the parent subnetwork 20, the child subnetwork 21 and the child subnetwork 26 can be started up in parallel at the same time. The time required can be shortened.

Although the above embodiment describes the case where four sub-networks are connected to each other by four high-speed digital lines, the present invention is not limited to this, and the present invention is not limited to this. It may also be used when connecting via a line. Further, in the above embodiments, each subnetwork is configured with three or four time division multiplexers, but the present invention is not limited to this. There are no particular restrictions on the number of devices, the number of high-speed digital lines, or the configuration of the subnetwork connecting these.

〔Effect of the invention〕

As described above, according to the present invention, a network consisting of a large number of time division multiplexing devices can be divided into a plurality of small-scale subnetworks and managed, and furthermore, a network management device and a primary station of each subnetwork can be managed. is configured to connect using the user line and extended network management information bits, which reduces the load on the primary station of each subnetwork, and also reduces the amount of data transferred when the network management device transfers network management information to the entire network. Moreover, the number of time division multiplexers in one subnetwork is reduced, and the number of relay stages in transferring messages from the secondary station to the network management device is reduced. It has the effect of reducing the delay of accompanying messages0

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a communication system according to an embodiment of the present invention, Fig. 2 is a frame block diagram showing the transmission frame format on the high-speed digital line, and Fig. 3 is a block diagram showing a conventional communication system. , FIG. 4 is a frame configuration diagram showing a transmission frame format on the high-speed digital line, and FIG. 5 is a configuration diagram showing a network for transferring network management information. 1 is a network management device, 2ai time division multiplexing device (primary station),
2b, 2c are time division multiplexers (secondary stations), 6, 6a~
3dH Mil 3dH high-speed digital terminal, 20 is a parent subnetwork, 21.22° 23 is a child subnetwork 0. In the figure, the same reference numerals indicate the same or equivalent parts. Patent Applicant: Mitsubishi Electric Corporation Figure 1 1: Network management device 2 (2: Nippon divisional power station (1; 'X station) 21-23: Child sub-network Figure 3 1: fI management unit Location: Terminal Figure 4 Figure 5 5: Frame 2d: Primary station (sub-dividing power heavy equipment) 2b: 2; Missing (day-ahead dividing power heavy equipment) 12: Service channel

Claims (1)

[Claims] A plurality of time division multiplexing devices are connected to each other by a high-speed digital line, and a network management device is connected to one of the time division multiplexing devices, and frames transmitted on the high-speed digital line are connected to each other. It is divided into a data area and a control area, and data from a plurality of terminals is transmitted by time division multiplexing in the data area, and network management information is transmitted between the time division multiplexing devices using network management information bits in the control area. In a communication system that transfers data, a plurality of time division multiplexers are connected via high-speed digital lines, and one of them is designated as a primary station,
A subnetwork is formed with the others as secondary stations, and a plurality of the subnetworks are interconnected by high-speed digital lines, one of them is used as a parent subnetwork and the others as child subnetworks, and the parent subnetwork The network management device is connected to the primary station of In the case of the child subnetwork directly connected to the parent subnetwork by a digital line, information between the child subnetwork and the network management device is transmitted in the data area as terminal data in the parent subnetwork. The data is transmitted to extended network management information bits provided in the control area on the high-speed digital line connecting the parent subnetwork and the child subnetworks, and In the case of a child subnetwork connected via a subnetwork, information between the child subnetwork and the network management device is transferred at high speed to the child subnetwork directly connected to the child subnetwork. It is transmitted using the extended network management bits of the control area on the digital line, and from there it is transmitted to the network management device within the child subnetwork and the parent subnetwork, and on the high-speed digital line that connects each of these subnetworks. A communication system characterized by transmitting terminal data in a data area.