JPS63237698A - Information communication network - Google Patents

Abstract

PURPOSE:To reduce the quantity of cables to be laid by assigning time slots on a tree-shaped time division multiplex transmission line in accordance with the request from a subscriber's apparatus or a local exchange. CONSTITUTION:The transmission line to which subscriber's apparatus 4 following a local exchange 2 are connected is constituted into a tree-shaped time division multiplex transmission line 5, and this tree-shaped time division multiplex transmission line 6 is used by the TDMA system. That is, the number of time slots set on the tree-shaped time division multiplex transmission line 5 is made smaller than the number of subscriber's apparatus 4 connected to the transmission line, and these time slots are properly assigned to subscriber's apparatus in accordance with requests from subscriber's apparatus 4 or the local exchange 2. Thus, the quantity of cables to be laid is considerably reduced and various service requests are flexibly coped with.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a highly flexible information communication network suitable for public information communication such as telephone calls and data.

(Prior Art) In a conventional information communication network (public network), as shown in Fig. 2, a plurality of local exchanges (LS) 2 are connected to a transit exchange (TS) 1, and a plurality of local exchanges (LS) 2 are connected to each other under these local exchanges 2. A plurality of remote line concentrators (RC3) 3 are connected to each of them. A large number of subscriber devices 4 (for example, telephones, data terminals, facsimile machines, etc.) are connected to this remote line concentrator 3. In addition, the above-mentioned relay exchange 1 is connected to other relay exchanges 1 in a mesh, tandem, loop, or star configuration via a higher order exchange, for example, to construct a nationwide large-scale information communication network. ing.

However, when the subscriber equipment 4 communicates information with another subscriber equipment 4 connected to the same remote line concentrator 3, the line connection is made via the remote line concentrator 3. In addition, when information is communicated with subscriber equipment 4 connected to another remote line concentrator 3, the remote line concentrator 3 connected to each of those subscriber apparatuses 4 connects to the upper local exchange 2.
The line connection is made through the intermediate switch 1 and, if necessary, through the higher-level relay exchange 1.

However, it is undeniable that establishing a new public information and communications network like this would require enormous amounts of time and expense. In particular, installing new communication cables (for example, twisted pair wires) between the remote line concentrator 3 and the subscriber equipment 4 requires a large amount of expense. For this reason, most of the construction of new public information and communication networks is only planned for companies between major cities. In other words, the reality is that no prospects have been set for the development of an inexpensive information and communications network for general subscribers.

On the other hand, in l5DN (integrated digital communication network), which is one of the subscriber services that will be put into practical use in the near future, twist
It is planned to implement two B 4 Kbps information channels (B channels) and a 113 Kbps control/data channel (D channel) using paired wires. However, in this 15DN, since the channels are fixed, there are problems such as, for example, normally only two telephones can use the information communication network at the same time.

Therefore, 15DN has developed a (23B+D) optical fiber system for large companies in order to meet the demand for preparing a high-speed channel only when holding a video conference or transmitting a large amount of data in a short period of time. It is planned to prepare primary rate service and H channel service.

However, in order for a general subscriber to receive this service, it is necessary to install a new optical fiber cable between the local exchange 2 and the subscriber equipment 3. It was inappropriate as a service for people.

(Problems to be Solved by the Invention) In the information communication network, for which various studies have been carried out in the past, there remain many issues in dealing flexibly with installation costs and various service requests. has been done.

The present invention was made in consideration of these circumstances, and its purpose is to minimize the amount of cables that need to be laid, and to provide flexible services to general subscribers. The goal is to provide an inexpensive information and communication network that can be used.

[Structure of the Invention (Means for Solving Problems)] The present invention provides a tree-like time division multiplex transmission path for the transmission path to which subscriber equipment below the local exchange is connected, and a tree-like time division multiplex transmission path. The transmission path is used in the TDMA system.

In other words, the number of time slots set on a tree-like time division multiplex transmission path is smaller than the number of subscriber devices connected to the transmission path, and the time slots are set as appropriate according to requests from subscriber devices or local exchanges. The information is assigned to that subscriber device.

(Function) According to the present invention, since the transmission path to which subscriber equipment is connected is tree-shaped, the amount of cable installation can be significantly reduced compared to a conventional star-shaped network.
The installation cost can be reduced.

Furthermore, since this tree-like network is used in TDMA, its time slots can be freely allocated according to service requests. Therefore, it becomes possible to flexibly deal with various service requests. In addition, since time slots are allocated according to service requests in this way, the number of time slots can be kept smaller than the number of subscriber devices, which has the effect of making effective use of communication resources. It will be done.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic configuration diagram of an information communication network according to the present invention. The features of this network are:
A transmission line 5 connected to the local exchange 2 and connected to a plurality of subscriber devices 4 is a tree-like time division multiplex transmission line,
This transmission path 5 is managed by a time division multiplex control device (TDMA) 6. The time division multiplex control device 6 and the local exchange 2 are connected by, for example, 30 information channels and 2 control information channels.

FIG. 3 shows the format of a signal that is time-divisionally communicated via such a time-division multiplex transmission line 5, and (a) shows the format of a signal transmitted from the time-division multiplex control device 6 to a plurality of subscriber devices 4. (b) shows the uplink signal format transmitted from a plurality of subscriber devices 4 to the time division multiplex control device 6.

As shown in this figure, one frame of the signal format is
B channel area for voice/data transmission.

It consists of a D channel area for control/data transmission, and a control area for transmitting communication control information between the time division multiplex control device 6 and the plurality of subscriber devices 4. These B channel areas and D channel areas are each divided into a plurality of time slots, and the time slots are respectively allocated to the subscriber equipment 4 in response to a time slot allocation request from the subscriber equipment 4. It becomes. Note that the number of time slots is set to be smaller than the number of subscriber devices 4 connected to the transmission path 5, since it is extremely rare for all of the subscriber devices 4 to have communication requests at the same time. ing.

In response to a request from the subscriber equipment 4 or a request from the local exchange 2, the time division multiplex control device B assigns each time slot of the B channel area and the D channel area to the information communication. Each subscriber device 4 that is directly involved is allocated independently according to its communication specifications.

The time slot allocation request from the subscriber equipment 4 and the time slot allocation by the time division multiplex control device 6 in response to this request are handled by the time slot allocation request from the subscriber equipment 4 using the control area set in one frame as described above. Response signal R3P
and a control signal ASG from the time division multiplex control device 6.

This time slot allocation control will be explained in more detail with reference to FIGS. 4 and 5.

Now, when the subscriber equipment 4, e.g. a standard telephone, goes off-hook, the subscriber equipment 4 will receive, e.g. 4K
Request slot allocation for D channel of bps (step a). The time division multiplex controller] receives this slot allocation request and sets the D channel time slot allocation for the subscriber equipment 4 via the ASG (step b).

To allocate a time slot for the D channel via this ASG, for example, the starting position of the time slot (the number of bits from the first bit of the frame, and the length of the slot if necessary) is determined by issuing the above slot allocation request. This is done by notifying the subscriber equipment 4.

The subscriber equipment 4 that has been assigned the time slot of the D channel in this way transmits dial information (information that specifies the communication partner) to the time division multiplex control device 6 through the designated time slot of the D channel. It will be transmitted to. Then, the dial information is given from the time division multiplex control device 6 to the local exchange 2 and further to the relay exchange I as required.

Predetermined call processing is then performed according to this dial information (step C). If a communication path can be established with the communication partner, the subscriber equipment 4 of the communication partner
Similarly, the D channel time slot assigned to the second communication partner subscriber equipment 4 is assigned to the D channel time slot assigned to the second communication partner subscriber equipment 4. Of course, this is different from the time slot of the D channel assigned to the D channel.

At this point, subscriber equipment 4 is assigned only the D channel time slot.

Thereafter, using the designated time slot of the D channel, a B channel slot for communicating audio information is allocated (step d), and at the same time, a ringing signal is transmitted using the B channel slot.

The time slot designation for the B channel is done by notifying the calling side and the communication destination subscriber equipment 4 of the slot position and number of bits, in the same way as the time slot designation for the D channel. I get angry. As a result, the subscriber equipment 4 is allocated a time slot of the B channel as well as a time slot of the D channel.

After receiving the designation of the B channel time slot through L7, the subscriber equipment 4 instructs the time division multiplex control device 6 to release the D channel time slot via the D channel time slot mentioned above. Notify (step e). Then, upon receiving this notification, the time division multiplex control device B releases the D channel time slots set for the subscriber equipment 4 as described above.

Therefore, at this point, only the time slot of the B channel is allocated to the subscriber equipment 4. Then, between the subscriber equipment 4 on the calling side and the communication partner, communication of audio information, that is, a telephone call, is performed using the time slot of the designated B channel as described above.

Thereafter, when the call ends, that is, when the subscriber equipment 4 hooks on, the time division multiplex control device 6 is notified of the end of the call via the RSP (step g). Upon receiving this notification of the end of the call, the time division multiplex control device 6 releases the B channel time slots assigned to each subscriber device 4 as described above.

FIG. 5 shows an example of the configuration of the time division multiplexing control device 6 that allocates and manages such time slots. , a slot allocation section 6b that receives this allocation request and allocates time slots to the subscriber equipment 4, and a channel management table Tie that manages the time slots allocated to the subscriber equipment 4.

In this channel management table 6C, which time slot is assigned to which line concentration distribution terminal is managed for each B channel and D channel. Then, when there is a slot allocation request, the allocation request detection unit 6a detects the channel management table E3.
With reference to c, an empty time slot is detected, or an area where the time slot can be installed is detected. The slot allocation unit 6b sets time slots to be allocated to the line concentration distribution terminals according to this detection information, and registers this information in the channel management table 6C.

Then, when that time slot is released, the slot allocation information registered in the channel management table 6c is deleted.

Note that the above description is just an example of time slot assignment in the case of communicating audio information, but time slot assignment in other cases is performed in the same manner.

Also mentioned above! If, for example, it is desired to only communicate packet data via the D channel instead of communicating voice information, the R3P is used to notify that fact. In this case, only time slot I. in the D channel is allocated.

Furthermore, for example, if communication using a B channel of 84 Kbps or more is required, that is, high-speed multidimensional exchange (bps to nX84), a plurality of time slots are allocated in the same way. Then, high-speed multidimensional exchange is performed using a plurality of time slots of the designated B channel.

Incidentally, the tree-shaped time division multiplex transmission line 5 described above may be constructed of a coaxial cable, an optical fiber cable, or the like. Also, the signal transmitted through the transmission line 5 is
It may be a baseband signal or a modulated signal.

In particular, when using a wideband transmission line, it is possible not only to use telephone voice and relatively low-speed data communication, but also to
It becomes possible to provide high-speed packet exchange services using the CSMA/CD system and multi-channel video services such as those seen on C5TV.

Note that the present invention is not limited to the embodiments described above. Although the local exchange 2 and the time division multiplex control device 6 have been described as separate devices here, the time division multiplex control device 6
It is also possible to realize this as part of the functions of the local exchange 2. Further, the number of subscriber devices 4 connected to the tree-shaped transmission path 5 is not particularly limited, and the number of time slots set in the transmission path 5 is also limited to the number of subscriber devices 4 connected to the transmission path 5. It is only necessary to determine the equipment and its operating rate in advance. In short, the present invention can be implemented with various modifications without departing from the gist thereof.

C. Effects of the Invention] As explained above, according to the present invention, since the transmission path to which subscriber equipment is connected is tree-shaped, the amount of cables laid can be reduced compared to the case of constructing a conventional star-shaped network. can be significantly reduced. As a result, an information communication network can be constructed at low cost. Furthermore, since the time slots of the transmission path are allocated using TDMA, it is possible to flexibly respond to various service requests, and the communication resources can be used effectively.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an information communication network according to an embodiment of the present invention, FIG. 2 is a configuration diagram of a conventional information communication network, and FIG. 3 is a tree-shaped time division multiplex transmission line according to the present invention. FIG. 4 is a diagram showing a time slot allocation procedure, and FIG. 5 is a diagram showing an example of the configuration of a time division multiplex control device. ■...Relay exchange, 2...Local exchange, 3...
- Remote line concentrator, 4... Subscriber equipment, 5... Tree-shaped time division multiplex transmission line, 6... Time division multiplex control device. Figure 1 Figure 2 Figure 3 Figure 4

Claims (3)

[Claims] (1) Interconnected relay exchanges, multiple local exchanges connected to these relay exchanges, tree-shaped time division multiplex transmission lines connected to each of these local exchanges, and these tree-shaped The number of time slots set in the tree-like time division multiplex transmission path is determined by the number of subscriber devices connected to the transmission path. An information communication network characterized in that time slots of the tree-shaped time division multiplex transmission path are allocated in response to requests from subscriber equipment or local exchanges. (2) The information communication network according to claim 1, wherein the time slot is configured to include at least an information channel or a control/data channel. (3) The information communication network according to claim 1, wherein time slot assignment is performed via dedicated time slots.