JP2561009B2 - Call forwarding method and device - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to call forwarding services in a telephone switching network.

[0002]

2. Description of the Related Art In the conventional call transfer service, as shown in FIG. 2, the transfer destination telephone number of the call transfer service subscriber is registered in an exchange accommodating the call transfer service subscriber, and the call transfer service subscriber is registered. When making a call to the transfer destination subscriber from the exchange that accommodates the transfer destination subscriber, the call is made unconditionally because the transfer destination subscriber cannot be identified as being idle or busy. Alternatively, the busy condition is determined. Therefore, if the transfer-destination subscriber is busy, between the exchange accommodating the transfer-destination subscriber and the exchange accommodating the transfer-destination subscriber until the calling subscriber hears the busy tone and goes on-hook with the telephone. The relay transmission line of is suspended.

Therefore, the busy state of the transfer destination subscriber can be identified by the exchange that accommodates the call transfer service subscriber, and between the exchange that accommodates the call transfer service subscriber and the exchange that accommodates the transfer destination subscriber. As a publicly known example for preventing invalid holding of a relay transmission line, a subscriber state identification method (Japanese Patent Laid-Open No. 6-242242)
2-095058). In this subscriber state identification method, a network service control database (NSP) is provided separately from the exchange accommodating the call transfer service subscriber, and the change in the idle or busy state of the call transfer service subscriber and the transfer destination subscriber is common. The call transfer service subscriber can identify whether the transfer destination subscriber is idle or busy by inquiring from the exchange accommodating the call transfer service subscriber at all times through the line signaling network. Before connecting the relay transmission line between the exchanges accommodating the transfer destination subscriber and the transfer destination subscriber, it is possible to prevent the relay transmission line from being invalidly held during busy.

[0004]

A part of the function of the network service control database (NSP) is that it is used to identify the free or busy state of a service subscriber for various subscriber services. In particular, the call transfer service is not the only purpose, so the scale becomes large. An object of the present invention is to enable a call transfer service subscriber to identify a transfer destination subscriber's vacant or busy state in a switchboard accommodating the call transfer service subscriber, prevent invalid hold of a relay transmission line, and perform a conventional operation. It is the same as above, and it is to be configured by simple means.

[0005]

According to the call transfer method in the call transfer service of the telephone exchange system of the present invention, the first subscriber exchange accommodating the call transfer service subscriber accommodates the transfer destination subscriber. When the telephone number of the transfer destination subscriber designated as the destination and the telephone number of the call transfer service subscriber requesting the call transfer are notified to the second subscriber switching device, the second subscriber switching device joins the transfer destination. The first subscriber exchange notifies the first subscriber exchange that the telephone is busy every time the person's telephone is busy, and the first subscriber exchange stores the busy display indicating the busy continuation and makes an arbitrary call. When a connection request from the subscriber to the call transfer service subscriber is detected, the presence / absence of the busy display is searched, and if there is the busy display, the busy tone or the talk is transmitted without transferring to the second subscriber exchange. Sending a middle talkie to the calling subscriber Have a method.

Further, the busy display of the second subscriber exchange is sent to the first subscriber exchange together with the telephone number of the call transfer service subscriber registered in the subscriber data of the transfer destination subscriber, and is busy. A call transfer method comprising the step of registering an indication with respect to subscriber data after a call transfer service subscriber's call transfer request.

Further, in the call transfer device in the call transfer service of the present invention, when the first subscriber exchange registers the transfer destination telephone number, the telephone number of the call transfer service subscriber is sent to the second subscriber exchange. A means for transmitting the telephone number of the transfer destination subscriber, the second subscriber switching system indicating that the transfer destination subscriber is busy every time the transfer destination subscriber is busy, and the telephone number of the call transfer service subscriber. Means for notifying the first subscriber exchange of the transfer destination, and when detecting a connection request from any calling subscriber to the call transfer service subscriber, the first subscriber exchange displays the busy indication of the transfer destination subscriber. Search for
Means for notifying the calling subscriber of the busy tone or busy talk without transferring to the second subscriber exchange if busy.

Further, the busy indication of the second subscriber exchange is transmitted to the first subscriber exchange together with the telephone number of the call transfer service subscriber registered in the subscriber data of the transfer destination subscriber, and is busy. A call transfer device having means for storing a display as subscriber data after a call transfer service subscriber's call transfer request.

[0009]

In the call transfer service of the present invention, the exchange that accommodates the subscriber of the call transfer service as described above is a means for notifying the idle or busy information of the transfer destination subscriber of the exchange that accommodates the transfer destination subscriber. Since the common line signaling network can always grasp the information, when the calling subscriber detects a connection request to the call transfer service subscriber, if the transfer destination subscriber is busy, an exchange that accommodates the call transfer service subscriber. Does not connect to the forwarding subscriber, but sends a busy tone or busy talk to the calling subscriber.

[0010]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1A is a connection system diagram of an embodiment of the call transfer method of the present invention. FIG. 1B shows subscriber data of a call transfer service subscriber (hereinafter referred to as service subscriber data). FIG. 1C shows subscriber data of the transfer destination subscriber (hereinafter referred to as transfer destination subscriber data). When the call transfer service subscriber 5 contracts for the call transfer service, the service subscriber data corresponding to the call transfer service subscriber 5 is updated in the subscriber exchange 4 accommodating the call transfer service subscriber 5 as shown in FIG. 1B. To do. The information input at this time is the telephone number of the call transfer service subscriber 5 and the telephone number of the transfer destination subscriber 8, and the service start / stop information and the idle / busy information of the transfer destination subscriber 8 stop at their initial values. , Set as free. Subsequently, the subscriber exchange 4 accommodates the telephone number of the transfer destination subscriber 8 and the telephone number of the call transfer service subscriber 5 based on the service subscriber data by a common line signaling network (not shown). It is transmitted to the subscriber exchange 7. The subscriber exchange 7 writes the telephone number of the call transfer service subscriber 5 in the transfer destination subscriber data corresponding to the transfer destination subscriber 8, and thereafter, the vacant / busy information of the transfer destination subscriber data is transferred by general connection processing. In synchronism with the update, the vacant / busy information and the call transfer service subscriber 5 are sent to the subscriber exchange 4 via a common line signaling network (not shown).
When the telephone number is transmitted, the subscriber exchange 4 updates the vacant / busy information of the service subscriber data according to the transmitted vacant / busy information. Meanwhile, call transfer service subscriber 5
When the service start operation is performed by the known technique, the service start / stop information of the service subscriber data is updated to start. Next, when the calling subscriber 1 dials the telephone number of the call transfer service subscriber 5, the call arrives at the subscriber exchange 4 via the subscriber exchange 2 and the relay exchange 3. The subscriber exchange 4 refers to the service subscriber data and is in the service start state, and if the transfer destination subscriber 8 is busy, the originating subscriber 1
Send a talking toki to. If the service subscriber data starts the service and the transfer destination subscriber 8 is empty, the calling subscriber 1 receives the call at the transfer destination subscriber 8 by a known technique, and if the service subscriber data is the service stop, the same applies. The call is transferred to the call transfer service subscriber 5 by a known technique.

[0011]

As described above, according to the present invention, in the exchange that accommodates the call transfer service subscriber, the idle or busy state of the transfer destination subscriber is received from the subscriber exchange that accommodates the transfer destination subscriber. Since the configuration to hold is realized, if the transfer destination subscriber is busy, the call is transmitted without invalidating the relay transmission path from the exchange that accommodates the call transfer service subscriber to the subscriber exchange that accommodates the transfer destination subscriber. By notifying the subscriber that the call is busy, the calling subscriber recognizes that the call transfer service subscriber is busy and goes on-hook. Therefore, invalid hold of the relay transmission line between the exchange accommodating the call transfer service subscriber and the exchange accommodating the transfer destination subscriber is prevented. In particular, subscribers who contract for call forwarding services have higher call traffic than general subscribers, and demand for call forwarding services is expected to increase over a wider area in the advanced information society.
In such an environment, invalid holding of the relay transmission line between the exchanges according to the present invention can be prevented by the above-mentioned simple identification means, and a great line use effect is brought about.

[Brief description of drawings]

FIG. 1A is a connection system diagram of an embodiment of a call transfer method of the present invention. (B) is subscriber data of the call transfer service subscriber. (C) is subscriber data of the transfer destination subscriber.

FIG. 2A is a connection system diagram of a conventional call transfer method.
(B) Subscriber data of a conventional call transfer service subscriber. (C) Subscriber data of the conventional transfer destination subscriber.

[Explanation of symbols]

 1 Calling subscriber 2, 4, 7 Subscriber switch 3, 6 Relay switch 5 Call transfer service subscriber 8 Transfer destination subscriber

Claims (4)

(57) [Claims] 1. A call transfer method in a call transfer service of a telephone exchange system, wherein a first subscriber exchange accommodating a call transfer service subscriber is a second subscriber exchange accommodating a transfer destination subscriber. On the other hand, when the telephone number of the transfer destination subscriber designated as the call destination and the telephone number of the call transfer service subscriber who has requested the call transfer are notified, the second subscriber switching unit will notify the callee of the transfer destination subscriber every time the telephone is busy. Is notified to the first local exchange that the busy is continuing, and the first local exchange stores the busy display indicating the busy, and the call transfer service from an arbitrary calling subscriber is performed. When a connection request to the subscriber is detected, the presence / absence of the busy display is searched, and when the busy display is present, the busy tone or the busy talkie is transmitted to the calling subscriber without transferring to the second subscriber exchange. Characterized by sending to Call transfer method. 2. The busy indication of the second subscriber exchange is sent to the first subscriber exchange together with the telephone number of the call transfer service subscriber registered in the subscriber data of the transfer destination subscriber, and is busy. 2. The call transfer method according to claim 1, wherein the display is registered as subscriber data after the call transfer service subscriber requests the call transfer. 3. The call transfer device in the call transfer service, wherein the first subscriber switching device registers the transfer destination telephone number with the second subscriber switching device when registering the transfer destination telephone number and the transfer destination telephone number of the subscriber. A means for transmitting the telephone number of the destination subscriber, and the second subscriber exchange displays the busy indication and the telephone number of the call transfer service subscriber for each busy of the transfer destination subscriber. A means for notifying the first subscriber exchange and a connection request to the call transfer service subscriber from an arbitrary calling subscriber are detected, and the first subscriber exchange detects whether the transfer destination subscriber has the busy display. And a means for notifying the calling subscriber of the busy tone or the busy talk without transferring to the second subscriber exchange if the call is being continued. 4. The busy indication of the second subscriber exchange is transmitted to the first subscriber exchange together with the telephone number of the call transfer service subscriber registered in the subscriber data of the transfer destination subscriber, and is busy. 4. The call transfer device according to claim 3, wherein the display is stored as subscriber data after the call transfer service subscriber requests the call transfer.