JPH05207161A - Incoming transfer system - Google Patents

Abstract

PURPOSE:To efficiently operate a speech line in a private exchange. CONSTITUTION:A No.7 signal system is used among a telephone station A of an originating call side, the telephone station B of a transfer source and the telephone station C of a transfer destination. When a call to a subscriber Y where incoming transfer is registered is detected, the telephone station B sets incoming transfer execution display CF, the number DN of a transfer destination subscriber Z and the signal point code PC of the telephone station C in the transfer destination as a parameter so as to return them to the telephone station A. The telephone station A transmits an IAM message to the telephone station C based on the signal point code PC and the subscriber number DN which are set so as to directly connect a call from the subscriber X to the telephone station C without relaying the telephone station B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a call transfer system within a private telephone network that extends over a plurality of telephone stations.

[0002]

2. Description of the Related Art In the conventional call transfer system, a subscriber X of a telephone station D dials a subscriber Y of a telephone station E as shown in FIG. F
If subscriber Z has been registered, the call is to central office F
Forwarded to subscriber Z of.

By the call transfer of the subscriber Y to the subscriber Z,
After all, the subscriber X of the calling telephone station D and the forwarding telephone station F
Although a two-party call with the subscriber Z is established, the call is always relayed from the telephone station D on the calling side to the telephone station E of the transfer source and connected to the telephone station F of the transfer destination. That is, after the call is transferred, the transfer-source telephone station E functions as a relay station.

However, while the call charge between the subscriber X and the subscriber Y is charged at the calling telephone station D, the call between the transfer source subscriber Y and the transfer destination subscriber Z is charged. The call charge is charged at the transfer source telephone station E.

[0005]

In the conventional call transfer method, the connection between the calling subscriber and the transfer destination subscriber is always at least three stations (source station, transfer source Station, transfer destination station). That is, the source station was never directly connected to the destination station.

This is because, firstly, since the originating station cannot know in advance which station is the transfer destination, it is not possible to select the telephone line to the transfer destination station from the beginning, and secondly, the transfer call. Is due to the two reasons that there is a restriction that the transfer source station must be charged.

In the case of a private telephone network that extends over a plurality of telephone offices, basically calls within the network are not charged,
For this reason, the call transfer call is still connected via three stations. It can be said that this is an inefficient connection form in terms of efficient operation of the private telephone network.

[0008]

According to the call transfer method of the present invention, in a call transfer method in a private telephone network that extends over a plurality of telephone stations, the originating station, the transfer source station and the transfer destination station are different from each other, and No. as an inter-station signal is transmitted between these stations. If the 7 signaling is used, the transferring station may not be able to access the N when the call to the subscriber for which the call transfer is registered is detected.
o. Incoming call transfer execution display using the 7-signal system user part, the transfer destination subscriber number and the signal point code of the transfer destination station are set as parameters and returned to the transmitting station. The transmitting station sets the signal point code and the subscriber. The IAM message is sent to the transfer destination station based on the number, and the call is directly connected to the transfer destination station from the calling station without relaying the transfer source station.

[0009]

The present invention will be described below with reference to the drawings.

FIG. 1 (a) is a diagram for explaining an embodiment of the present invention relating to an incoming call transfer method in a private telephone network that extends over a plurality of telephone stations, and FIG. It is a figure for demonstrating the protocol of a 7-signal system. Here, between the telephone stations A, B, and C, the No. It is assumed that the 7-signal system is used.

The operation will be described below. Calling station A
When subscriber X of the subscriber dials subscriber 7 of telephone station B, telephone station A sends an initial address to telephone station B.
The ss message (IAM) is sent. If the subscriber Y of the central office B has registered the call transfer to the subscriber Z of the central office C, the central office B of the transfer source again communicates to the central office C of the transfer destination with an Initial Address message (IAM). ) Is sent to the originating station at the same time.
Call transfer execution display C using the user part in the 7-signal system
F, a destination subscriber number DN, and a Call Point message (CPG) in which the signal point code PC of the destination station is set are returned.

Upon receiving the CPG message, the telephone station A on the calling side directly sends the IAM message with the call forwarding rerouting display to the telephone station C of the forwarding destination based on the signal point code and the forwarding destination subscriber number. At telephone station C,
When the IAM message with the call transfer rerouting display is received, the address comp
A return message (ACM) is sent back to establish a call connection, while a Release message (REL) is sent back to the transfer-source telephone station B to take a measure to release the call connection via the telephone station B. .. At this time, the originating telephone station A
IAM message from IA from transferer B
Always check that the calling subscriber numbers in the M messages are the same.

If the transfer-destination telephone station C receives the IAM message from the transfer-source telephone station B, the call-transmission-side telephone station A receives the IAM with the call transfer rerouting display.
If you cannot receive the message after waiting for a certain period of time,
Return the ACM message to the forwarding station, B,
The call is connected via the central office B.

[0014]

As described above, according to the present invention, in the call transfer method in the private exchange network that extends over a plurality of telephone stations,
The transfer source station is No. Using the 7-signal system user part, the call transfer execution display, transfer destination subscriber number and signal point code of the transfer destination station are set as parameters and returned to the transmitting station, and the transmitting station is not relayed from the transmitting station. Since it is configured to directly capture the call line to the transfer destination station and connect the call,
There is an effect that it is possible to efficiently operate a call line in the private exchange network without wastefully using the call transfer service by implementing the call transfer service.

[Brief description of drawings]

FIG. 1 (a) is a diagram for explaining an embodiment of an incoming call transfer system according to the present invention. (B) is No. in (a). It is a figure for demonstrating the protocol of a 7-signal system.

FIG. 2 is a diagram for explaining a conventional call transfer method.

[Explanation of symbols]

A, B, C Telephone station X, Y, Z Subscriber DN Subscriber number CF Call transfer execution display PC Signal point code ACM Address Complete message CPG Call Progress message IAM Initial Address message REL Release message

Claims (1)

[Claims] 1. In an incoming call transfer method within a private telephone network that extends over a plurality of telephone stations, a calling station, a transfer source station, and a transfer destination station are different from each other, and No. If the No. 7 signaling is used, the transferor station may detect the call to the subscriber when it detects a call to a subscriber for which call transfer is registered. Incoming call transfer execution display using the 7-signal system user part, the transfer destination subscriber number and the signal point code of the transfer destination station are set as parameters and returned to the transmitting station. The transmitting station sets the signal point code and the subscriber. IAM based on number
A call transfer method in which a message is sent to a transfer destination station, and the call is directly connected to the transfer destination station from the calling station without relaying the transfer source station.