JPH03159342A - Isdn switching system - Google Patents

Abstract

PURPOSE:To reduce a load on software by connecting a packet switching device to an analog trunk housing device, and connecting it to a digital trunk housing device via a time division speech path. CONSTITUTION:In an ISDN exchange 1, an ISDN subscriber housing device 110 houses an ISDN subscriber terminal 112. A packet switching device(PKE) 120 is housed in a time division speech path switch(TDSW) 100, and also, it is connected to a public packet switching network 3. And the public packet switching network interface of the PKE 120 is connected to a packet interface circuit 131 loaded on the analog trunk housing device 130, and is connected to the digital trunk housing device 140 via the TDSW 100, and is connected to a digital multiplexing circuit 141. Thereby, it is not required to be conscious of the fact that a call is a packet switching call with a switching system, and the load on the software is reduced.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an ISDN switching system, and in particular to an ISDN switching system.
The present invention relates to an ISDN switching system in which one digital line accommodated in the switching system is shared by circuit-switched calls and packet-switched calls.

[Conventional technology]

Conventionally, there has been no suitable equipment for accommodating packet-switched calls and circuit-switched calls on digital lines. For this reason, there are methods such as converting the packet network interface of a packet switching device into an analog signal using a modem and multiplexing this analog signal with other analog trunks via a channel bank, and accommodating the digital line of the switching device. A second method has been common, adding special circuitry to the device to accommodate a dedicated interface for accommodating the data link.

[Problem to be solved by the invention]

However, in the first conventional method described above, it is necessary to carry out the unnecessary process of converting the output of the packet switching device, which is originally a digital signal, into an analog signal using a modem. Furthermore, even if the second method is used, a special interface is required to accommodate packet-switched calls to digital lines, so the digital line accommodation device of the exchange is a digital line accommodation device that is used only for general circuit-switched calls. The disadvantage is that it requires extra circuitry compared to .

SUMMARY OF THE INVENTION An object of the present invention is to provide an ISDN switching system that minimizes changes in hardware and software, addition of functions, etc. for accommodating packet-switched calls and circuit-switched calls to digital lines.

[Means to solve the problem]

The ISDN switching system of the present invention accommodates ISDN subscriber accommodating equipment, telephone subscriber accommodating equipment, analog trunk accommodating equipment, digital trunk accommodating equipment, and packet switching equipment in a time-division communication path, and provides circuit switching functions and packet switching. In the switching system, the analog trunk accommodating device includes an interface circuit for commonly using one digital line for circuit-switched calls and packet-switched calls; The interface circuit is connected to the interface circuit of an analog trunk accommodation device, and a channel corresponding to the interface circuit of the analog trunk accommodation device is connected to the digital trunk accommodation device via the time division communication path, and the interface The circuit is characterized by being the same as a general packet network interface circuit.

〔Example〕

Next, the present invention will be explained with reference to the drawings. FIG. 1 is a system block diagram showing one embodiment of the present invention. In the I SDN exchange 1, an ISDN subscriber accommodation equipment (hereinafter referred to as LE) 110 is an ISDN subscriber terminal (hereinafter referred to as SU).
B) 112 is accommodated via the subscriber line 111. A packet switching equipment (hereinafter referred to as PKE) 120 for realizing the packet switching function of the switching system is housed in a time division channel switch (hereinafter referred to as TDSW) 100 and is connected to a public packet switching network (hereinafter referred to as NW) 3. is a common connection. That is, the ISDN switching system of this embodiment processes packet calls using X. 31 has the function performed by Case B. However, it is not always economical to connect the NW3 to the ISDN exchange through a normal interface. Therefore, in this embodiment, PKE
120 public packet switching network interfaces are connected to a packet interface circuit (hereinafter referred to as PKI) 13 mounted on an analog trunk accommodation device (hereinafter referred to as ATR) 130.
1, connect to a digital trunk receiving device (hereinafter referred to as DTR) 140 through TDSWIOO, and connect to a digital multiplex line 141. Note that the PKI 131 may be the same as a general packet network interface circuit used for testing data terminals.

A plurality of time slots are multiplexed on the digital multiplex line 141, and the allocation of the time slots for circuit switching and packet switching is determined by the respective communication volumes of the system.ATR 130 and DT
Connection with R140 is made semi-permanently by TDSWIOO according to instructions from the control program of the exchange system.
The connection between the LE 110 and the PKE 120 is made by identifying whether the call is a packet-switched call or a circuit-switched call when the SUB 112 makes a call, and then connects the call in the case of a packet-switched call. If we look at this embodiment from the software of the exchange system, T
A connection 101 within DSWIOO is included in normal packet switching processing, and a connection 102 corresponds to a semi-permanent connection (near readup connection) of normal circuit switching. In other words, it can be said that in connection 102, the switching system does not need to be aware that the call is a packet call. Therefore, according to this embodiment, the burden on the software is reduced.

Next, FIG. 2 is a system block diagram showing another embodiment of the present invention, in which a packet-switched call is accommodated in a public packet-switched network at the relay switch level. In FIG. 2, packet-switched calls multiplexed with circuit-switched calls on digital multiplex line 141 are connected to transit switch 2. In FIG. Relay switch 2 is public packet switch w4 (NW) 3
It is possible to interface with. DTR240, ATR230 PKI231 in FIG. 2 are the same as DTR140, ATR130. PKI13
Same as 1. 200 is a TDSW of the transit exchange 2. In the trunk exchange 2, the time slots carrying circuit-switched calls and the time slots carrying packet-switched calls are separated in the TDSW 200, and circuit-switched calls are sent to another DTR 240.
The packet-switched call goes to the digital multiplex line 241 via the NW via the PKI 231 installed in the ATR 231.
3/\Connected.

〔Effect of the invention〕

The present invention configured as described above has the following effects.

In other words, in general, the spread of packet-switched networks is due to the spread of circuit-switched networks,
In particular, packet-switched networks often lag behind compared to telephone networks, and therefore packet-switched networks are often small in scale. In this case, it is not economical to establish a direct connection from each subscriber exchange to the packet switch.Moreover, in the initial stage, data communications may require less data communication than circuit-switched calls when compared with bearers. Therefore, except in special cases, it is often not possible to expect enough traffic to allocate a digital line just for packet-switched calls.

In such a case, according to the present invention, it becomes easy to share the trunk line between a circuit switched call and a packet switched call.

Furthermore, since the switching system does not need to be aware that the call is a packet switched call, the burden on the software is reduced.

Furthermore, the interface circuit installed in the analog trunk accommodation device can be the same as the circuit used by the switching system to accommodate data terminals and the like for purposes such as testing the switching system.

[Brief explanation of the drawing]

FIGS. 1 and 2 are system block diagrams showing one embodiment and other embodiments of the present invention. 1...I SDN switch, 2...Relay switch, 3...
・・Public packet switching network (NW>.100,200・・
・Time division switch (TDSW), 101 1
02...Connection within TDSWIOO, 110...IS
DN subscriber accommodation equipment (LE), 111...I SDN
Subscriber line, 112...I SDN subscriber terminal (SUB
), 120...Packet exchange equipment (PKE), 121
...Public packet switching network interface, 122.
... Interface between packet switching device and analog trunk accommodation device, 130, 230... Analog trunk accommodation device (ATR) 131 231... Packet interface circuit (PK I) 140, 2
40...Digital trunk receiving device (DTR), 14
1,241...Digital relay line.

Claims (1)

[Claims] 1. An ISDN subscriber accommodation device, a telephone subscriber accommodation device, an analog trunk accommodation device, a digital trunk accommodation device, and a packet switching device are accommodated in a time-division communication path, and a circuit switching function and a packet switching function are provided. In the switching system, the analog trunk accommodation device includes an interface circuit for commonly using one digital line for circuit-switched calls and packet-switched calls, and the packet network interface circuit of the packet switching device and the analog An ISDN switching system characterized in that the interface circuit of the analog trunk accommodation device is connected to the digital trunk accommodation device, and a channel corresponding to the interface circuit of the analog trunk accommodation device is connected to the digital trunk accommodation device via the time division communication path. . 2. The ISDN switching system according to claim 1, wherein the interface circuit is the same as a general packet network interface circuit.