JP2687745B2 - Retry wait time setting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication device for connecting a line by utilizing a switching service of a communication network, and a retry waiting for setting a waiting time from when the line connection request is abandoned until the line connection request is issued again. Regarding the time setting device.

Generally, as a method of communicating between a plurality of stations on a communication network, there are a method of using a dedicated line and a method of using a switching service of the communication network.

The former is a method of performing communication using a line that is always connected. On the other hand, the latter is a method of performing line connection and communication using the exchange service of the communication network only when a line connection request is generated. The switching services in this case include, for example, a circuit switching service and a storage switching service.

In the latter communication method, when each station simultaneously issues a line connection request, a so-called incoming / outgoing call collision occurs in which the line connection request from the originating station and the line connection request from the terminating station collide. When this incoming / outgoing call collision occurs, it may not be possible to establish a line connection between the two stations.

For this reason, in this communication method, a retry function is provided to deal with the inability to connect when an incoming and outgoing call collision occurs. Here, the retry function is a function of once abandoning a line connection request and issuing a line connection request again after a lapse of a predetermined time when the line connection cannot be established.

By using this retry function, the line can be connected even if the incoming and outgoing call collision occurs.

However, when this retry function is provided, the time (hereinafter referred to as "retry waiting time") from the abandonment of the line connection request (hereinafter referred to as "call abandonment") to the time of issuing the line connection request again is set. Depending on the method, the connection response characteristic of the communication network may be significantly deteriorated.

Therefore, when the retry function is provided, a retry waiting time setting method that does not deteriorate the connection response characteristic of the communication network is desired.

[0009]

2. Description of the Related Art Conventionally, the following two methods have been adopted as methods for setting the retry waiting time. A method of setting the retry wait time at each station in a pseudo-random manner. A method of setting different retry wait times in advance for stations that may be connected.

However, in the setting method, since the retry waiting time is set in a pseudo-random manner, there is a possibility that collision of incoming and outgoing calls may occur many times depending on the retry waiting time that is set.

In such a case, since it is necessary to repeat the retry operation many times, the time from when the line connection request is first issued until the line connection is completed (hereinafter referred to as "line connection time") is specified. In addition to being unable to do so, this line connection time may increase.

Similarly, in the above method, not only is it necessary to manage the retry wait time for all stations that can be connected, but in the case of connecting stations with long retry wait times, Line connection time becomes long.

From the above, in the conventional retry waiting time setting method, the connection response characteristic of the communication network may be deteriorated.
Therefore, when the exchange service is used for emergency communication such as backup of a dedicated line, the backup function may not be sufficiently performed.

[0014]

As described above, conventionally, each station sets a pseudo-retry waiting time in a pseudo-random manner, and each station having a connectable possibility sets a different retry waiting time. There is a problem that the line connection time may become long.

Therefore, an object of the present invention is to provide a retry waiting time setting device capable of shortening the line connection time by shortening the retry waiting time and reducing the number of retries.

[0016]

FIG. 1 is a block diagram showing the principle configuration of the present invention.

In the figure, reference numeral 11 transmits the own station identification information for identifying the own station and the priority order identification information for identifying the communication priority order of the own station to the opposite station desiring the line connection. It is a means for transmitting identification information.

Reference numeral 12 is an abandonment judging means for judging whether or not the line connection request of the own station is abandoned.

Reference numeral 13 is an incoming / outgoing call collision judgment for judging whether or not the line connection requests of the own station and the opposite station collide with each other, based on the identification information of the opposite station and the own station identification information sent from the other station. It is a means.

Reference numeral 14 indicates whether or not the priority order of the own station is higher than the priority order of the opposite station, based on the priority order identification information sent from the own station and the priority order identification information sent from the opposite station. Is a priority order determination means for determining.

When the abandonment judging means 12 judges that the line connection request has been abandoned, and the originating / incoming call collision judging means 13 judges that the line connection request has collided.
When the priority determining unit 14 determines that the priority of the own station is higher than the priority of the opposite station, the first retry waiting time is set as the retry waiting time, and the priority of the own station is the opposite station. When it is determined that the priority is lower than the priority order, the wait time setting means sets a second retry wait time longer than the first retry wait time.

[0022]

In the above configuration, if a call origination / termination call collision occurs before the response to the line connection request is returned from the opposite station, if the priority of the own station is higher than the priority of the opposite station, the first station The retry waiting time is set, and at the opposite station,
A second retry wait time is set.

On the other hand, if the priority of the own station is lower than the priority of the opposite station, the second retry waiting time is set in the own station, and the first retry waiting time is set in the opposite station.

As a result, the retry operation is executed in the own station and the opposite station with different retry waiting times.

Therefore, even if the retry operation is executed after the call abandonment due to the incoming and outgoing call collision occurs, the incoming and outgoing call collision does not occur. In principle, line connection is made by one retry operation and with a short first retry waiting time.

As a result, the line connection time can be shortened.

[0027]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 2 is a block diagram showing the configuration of one embodiment of the present invention.

In the following description, a case where the present invention is applied to a retry waiting time setting device of a communication device connected to an integrated service digital network (hereinafter referred to as "ISDN network") will be described as a representative example.

FIG. 3 is a block diagram showing a schematic configuration of a communication system using the ISDN network.

In the figure, 20 is an ISDN network.
Reference numeral 30 is a communication device of stations A and B connected to this ISDN network 20.

In the communication device 30, S, T and R are I
An access point to the SDN network, that is, an interface between the user and the ISDN network 20 (hereinafter referred to as "user / network interface") is shown. This user / network interface S, T, R is CCITT Recommendation I.S. It is the same as that defined in 411.

Reference numeral 31 denotes a data terminal device having an existing interface (for example, an interface defined in CCIT Recommendations V.24 and V.28) that cannot be directly connected to the user / network interface S / T on the ISDN network 20 side. Is.

Reference numeral 32 is an adapter device for converting an interface signal on the user / network interface R of the data terminal device 31 into a signal that can be supplied to the user / network interface S / T.

The contents of the part on the ISDN network 20 side from the user / network interface S / T (frame structure on the interface, time slot allocation in the frame, network control procedure, transmission control procedure in the network, etc.) are as follows: CCITT I
It is the same as the content specified in the series recommendation.

The above is a schematic configuration of an example of a communication system using the ISDN network 20.

This embodiment is characterized by the configuration of the adapter device 32 of the communication device 30. FIG.
The configuration of the adapter device 32 is shown as a representative example of the adapter device 32 on the station A side.

Since the configuration of the adapter device 32 on the station B side is the same as the configuration of the adapter device 32 on the station A side, a description thereof will be omitted.

In the adapter device 32 of FIG.
Is a network interface unit connected to the ISDN network 20.

The network interface unit 321 performs disassembly and assembly of frames, establishment of synchronization, control of a protocol used for passing control information, and the like.

As a result, this network interface unit 32
Data communication information is transmitted and received between the data communication device 1 and the data terminal device 31 via the data communication channel 322. In addition, transmission and reception of network control information is performed with the network control unit 323 described later via the control information communication channel 324.

The network control section 323 controls the network by transmitting and receiving network control information to and from the ISDN network 20 via the network interface section 321. The network control means exchange control of outgoing and incoming calls, etc., and its specific sequence and state transition are described in CCITT Recommendation Q9.
31, I451.

The network control unit 323 also sets the retry waiting time. This retry waiting time setting function will be described later.

Reference numeral 325 denotes a local station retry control information holding unit which holds the local station retry control information.

Here, the retry control information is information used for setting the retry waiting time, and is used for identifying the own station identification information for identifying the own station and the communication priority of the own station. And priority identification information.

This retry control information is supplied to the retry control information transmission section 326 and the priority order determination section 329.

The retry control information sending unit 326 sends the retry control information to the control information communication channel 324 according to the instruction from the network control unit 323.

The network control unit 323 sends line connection request information to a station (opposite station) that desires line connection,
The retry control information sending unit 326 is instructed to send the retry control information.

As a result, the retry control information is sent to the opposite station while being inserted in the predetermined area of the line connection request information.

Reference numeral 327 is a retry control information receiving section. The retry control information receiving unit 327 follows the instruction from the network control unit 323 when there is a line connection request from another station (when there is an incoming call), and retries control information from the line connection request information on the control information communication channel 324. Only selectively receive.

The contents of this reception are supplied to the network controller 323. The network control unit 323 determines whether or not the received line connection request information includes the retry control information, based on the received content.

If the retry control information is included, the network control section 323 determines whether or not the retry control information is sent from the opposite station.

If it is sent from the opposite station, it instructs the retry control information receiving section 327 to supply the retry control information to the received retry control information holding section 328.

The network controller 323 makes the above-described two determinations in order to determine whether an incoming / outgoing call collision has occurred. In this case, if the retry control information is included and the retry control information is sent from the opposite station, it is determined that the incoming and outgoing call collision has occurred.

The retry control information of the opposite station supplied to the reception retry control information holding unit 328 is the network control unit 32.
According to the instruction of No. 3, it is supplied to the priority order determination unit 329.

The priority order determination section 329 includes priority order identification information contained in the retry control information of the own station supplied from the own station retry control information holding section 325 and the opposite station supplied from the reception retry control information holding section 328. It is determined whether or not the priority of the local station is higher than the priority of the opposite station based on the priority identification information included in the retry control information.

This judgment is made in accordance with the instruction of the network controller 323, and the judgment result is supplied to the network controller 323.

In addition to the functions described above, the network control section 323 sends line connection request information including the identification information of the opposite station to the control information communication channel 324 when receiving a line connection request from the data terminal device 31. Have the function to In this case, the network control unit 323 instructs the retry control information sending unit 326 to send the retry control information, as described above.

Further, the network control unit 323 determines whether or not the call is abandoned by monitoring the response message from the ISDN network 20 in response to the line connection request.

Further, when there is a call abandonment due to the incoming / outgoing call collision, the network control unit 323 resets the retry waiting time based on the determination result of the priority determination unit 329.

In other words, the network control unit 323, in the state where the line connection request is being issued (during transmission), before the line response from the remote station is returned to the line connection request (incoming call) from the remote station. ) And the line connection request is abandoned, the retry waiting time is reset.

In this case, as the retry waiting time, if the priority of the own station is higher than the priority of the opposite station, the first waiting time is set.
Is set, and if it is low, the second retry waiting time which is longer than the first retry waiting time is set.

After that, the network control unit 323 retransmits the line connection request information based on the newly set retry waiting time.

The above is the configuration of an embodiment for setting the retry waiting time.

When the ISDN network is used as the communication network, the call setup message can be used as the line connection request information. See CCITT for the format and information element coating of this call setup message.
Recommendation I. 451 and Q931.

In this case, the network number of each station in the ISDN network can be used as the retry control information. This is because the network number has the identification function of its own station and the identification function of the priority order.

When the network number is used as the retry control information, this network number is used as the control information communication channel 324 in CCITT Recommendation I.264. 451 and D specified in Q931
It is sent using the channel and inserted into the calling number area of the call setup message. Here, the calling number area is an area used for the purpose of notifying the called station of the network number of the calling station.

The retry waiting time setting operation in the above configuration will be described. In the following description, a case where a call setup message is used as the line connection request information and a network number is used as the retry control information will be described as a representative.

FIG. 4 and FIG. 5 are flowcharts showing the entire sequence at the time of calling.

In FIG. 4, first, the call origination is activated (step S1). That is, the data terminal device 31
A line connection request is given from the network control unit 323.

When this transmission activation is activated, the network control unit 3
23 gives a call origination request to the ISDN network 20 (step S2). That is, the network control unit 323 gives the ISDN network 20 a call setup message including the identification information of the opposite station.

At this time, the retry control information transmitting section 326
Sends the network number of its own station to the control information communication channel 324. As a result, a call setup message in which the own network number is inserted in the calling number area is supplied to the ISDN network 20.

When the transmission request has been supplied, the network controller 3
23 enters a state of waiting for a response from the ISDN network 20 (step S3).

If there is a response, the network control unit 323 determines the content (step S4). The response content includes a connection response and a call abandonment response. Here, the connection response is a response indicating that a line connection has been established with the opposite station. Also,
The call abandonment response is a response that prompts the abandonment of the line connection request.

When there is a connection response, the network control unit 323 notifies the data terminal device 31 that data communication is possible (step S5). As a result, the data communication information is transmitted from the data terminal device 31 via the data communication channel 322.

On the other hand, if there is a call abandonment response, the network controller 32
In step 3, the line connection request is abandoned, and it is determined whether or not the number of retries after the start of transmission has exceeded a predetermined number.

When the number of retries exceeds the predetermined number,
The network control unit 323 notifies the data terminal device 31 that data communication is impossible (step S7).

On the other hand, if the number of retries has not exceeded the predetermined number, the network controller 323 determines whether or not an incoming / outgoing call collision has occurred (step S8 in FIG. 5).

If no incoming / outgoing call collision has occurred, the network control section 323 resets the retry waiting time T1 currently set (step S9).

On the other hand, if there is an incoming / outgoing call collision, the priority order determination unit 329 is instructed to determine the priority order. As a result, the priority determination unit 329 determines the priority (step S10).

By this determination processing, when the determination result that the priority of the own station is higher than the priority of the opposite station is obtained,
The network control unit 323 determines a retry waiting time T different from T1.
2 (first retry waiting time) is set (step S
11).

At this time, the opposite station sets a retry waiting time T3 (second retry waiting time) longer than the retry waiting time T2. This is the opposite station (incoming station)
Then, it is determined that the priority order of the own station (incoming station) is lower than the priority order of the opposite station (originating station).

On the other hand, when the determination result that the priority order of the own station is lower than the priority order of the opposite station is obtained, the network control section 323.
Sets a retry waiting time T3 (second retry waiting time) (step S12).

At this time, the retry waiting time T2 is set in the opposite station (incoming station). This is because the opposite station (incoming station) determines that the priority order of the own station (incoming station) is higher than the priority order of the opposite station (originating station).

After that, the network control unit 323 monitors the elapse of the newly set retry waiting time (step S1).
3) When this retry waiting time elapses, the process returns to step S2 of FIG. 4 and the line connection request is sent again. Less than,
The above operation is repeated.

The case where the retry waiting time T1 is set is the case where the call is abandoned although the incoming and outgoing call collision does not occur. In this case,
For example, it is possible that the opposite station is communicating with another station. Therefore, in this case, the retry operation may be repeated several times. Thus, in this case,
There is a possibility that a communication impossible notification will be given in step S7 via step S6.

On the other hand, the retry waiting time T2 or T3
Is set when the call is abandoned due to the incoming and outgoing call collision.

In this case, as described above, when the retry waiting time T2 is set in the own station, the retry waiting time T3 is set in the opposite station.

On the contrary, when the retry waiting time T3 is set in the own station, the retry waiting time T2 is set in the opposite station.

Therefore, in principle, the line connection is made by one retry operation and with the shorter retry waiting time T2.

As a result, the line connection time from the start of transmission to the line connection is shortened.

FIG. 6 is a flow chart showing the specific contents of the call collision determination step S8 and the priority determination step S10 of FIG.

In the figure, steps S21 and S22 correspond to the call collision determination step S8. Also, step S2
3 corresponds to the priority determination step S10.

In step S21, the network controller 323
It is determined whether the received call setup message includes a network number. This determination is made by checking the received contents supplied from the retry control information receiving unit 327 as described above.

If the network number is not included, it is determined that there is no incoming / outgoing call collision, and the process of step S9 in FIG. 3 is performed.

On the other hand, if the network number is included, the process of the next step S22 is performed.

Note that the network number may not be included in the ISDN network because the insertion of the network number is not mandatory and is optional. In this case, even if there is an incoming / outgoing call collision, the priority order cannot be determined, so that there is no incoming / outgoing call collision.

At step S22, the network controller 323
It is determined whether or not the network number included in the line connection request information matches the network number of the opposite station.

If the two network numbers do not match, it is determined that the incoming and outgoing call collision does not occur, and the process of step S9 in FIG. 5 is performed.

On the other hand, if the two network numbers match, it is determined that an incoming / outgoing call collision has occurred, and the process of step S23 is performed.

In this step S23, the priority determination unit 329 compares the network number of the own station with the network number of the opposite station to determine whether the priority of the own station is higher than that of the opposite station. Is determined (step S23). This determination is made according to the instruction of the network control unit 323 as described above.

If it is determined that the priority of the local station is high, the process of step S11 of FIG. 5 is performed, and if it is determined to be low, the process of step S12 of FIG. 5 is performed.

According to this embodiment described in detail above, it is possible to shorten the line connection time when an incoming and outgoing call collision occurs.

This is because once the line connection request is made, the identification information of the own station and the priority order identification information are sent to the opposite station so that the retry waiting time of both poles has a difference. This is because the line connection can be performed by the retry operation and the shorter retry waiting time T2.

Further, since the network number is used as the retry control information, there is an advantage that it is not necessary to separately prepare the priority order identification information.

This is because the network number has a communication priority identification function in addition to its own identification function.

Further, according to such a configuration, there is an advantage that the management for preventing the overlapping of the priorities is unnecessary.

This is because the network number of each station is different for each station, so that a situation in which the network numbers do not overlap later does not occur unless the setting of the network number is made in advance.

The embodiment of the present invention has been described above.
The present invention is not limited to such an embodiment.

For example, in the above embodiment, the case has been described in which it is determined whether or not a call is abandoned, and then it is determined whether or not there is an incoming / outgoing call collision.

However, according to the present invention, the determination may be performed in the reverse order. Further, the call abandonment determination, the incoming / outgoing call collision determination, and the priority determination may be simultaneously performed by hardware, for example.

In the above embodiment, the present invention is ISD.
The case where the invention is applied to the retry waiting time setting device of the communication device connected to the N network has been described, but the present invention is also applicable to the retry waiting time setting device of the communication device connected to the communication network other than the ISDN network. is there.

Further, although the case where the present invention is applied to the retry waiting time setting device of the communication device using the circuit switching service has been described in the above embodiment, the present invention is applied to the communication waiting device of the storage switching service. It can also be applied to a retry waiting time setting device.

In addition to this, the present invention can of course be variously modified without departing from the scope of the invention.

[0114]

As described in detail above, according to the present invention,
By reducing the retry waiting time and reducing the number of retries, it is possible to provide a retry waiting time setting device capable of shortening the line connection time.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a principle configuration of a retry waiting time setting device according to the present invention.

FIG. 2 is a block diagram showing a configuration of one embodiment of the present invention.

FIG. 3 is a block diagram showing a schematic configuration of a communication system using an ISDN network.

FIG. 4 is a flowchart showing an overall sequence at the time of making a call according to an embodiment.

FIG. 5 is a flowchart showing an overall sequence at the time of making a call according to an embodiment.

FIG. 6 is a flow chart diagram showing an outgoing / incoming call collision determination and priority determination sequence of FIG.

[Explanation of symbols]

 11 identification information transmitting means 12 abandonment judging means 13 outgoing / incoming call collision judging means 14 priority order judging means 15 retry waiting time setting means

Claims (6)

(57) [Claims] 1. A line connection request from a transmitting station to an opposite station, and a line connection from a receiving station to an opposite station, which are respectively provided in a plurality of stations connected to each other by using a switching service of a communication network. In a retry waiting time setting device that sets a waiting time for a retry operation executed when a request conflicts, a priority order for identifying a communication priority order of the own station when a line connection request is made to the opposite station. the identification information, based on the identification information transmitting means for transmitting to the opposite station to the desired line connection, the priority identification information of its own station, the priority identification information transmitted from the opposite station, the priority of its own station Priority determining means for determining whether or not the priority is higher than the priority of the opposite station, and when the line connection request from the own station and the line connection request from the opposite station collide, the priority is given. For ranking judgment means If it is determined that the priority of the own station is higher than the priority of the opposite station, the first waiting time is set as the waiting time for the retry operation, and the priority of the own station is higher than the priority of the opposite station. When it is determined to be low, a waiting time setting means for setting a second waiting time longer than the first waiting time as a waiting time for the retry operation, and a retry waiting time setting. apparatus. 2. The outgoing / incoming call collision determining means (13) determines whether or not the line connection request has collided when the abandonment determining means (12) determines that the line connection request has been abandoned. 2. The retry waiting time setting device according to claim 1, wherein 3. The priority determining means (14) is configured to determine the priority when the outgoing / incoming call collision determining means (13) determines that a line connection request has collided. The retry waiting time setting device according to claim 1, wherein 4. The communication network is an ISDN network, the line connection request is made by transmitting a call setup message of the ISDN network, and the own station identification information and the priority identification information are the network of the ISDN network. The retry waiting time setting device according to claim 1, wherein the network number is a number and is transmitted in a state of being inserted in the calling number area of the call setting message. 5. The retry waiting time setting device according to claim 1, wherein the switching service is a circuit switching service. 6. The retry waiting time setting device according to claim 1, wherein the exchange service is a store and exchange service.