JPH04354440A - Communication equipment - Google Patents

Abstract

PURPOSE:To improve the operability of the operator at dialing by devising the equipment such that its communication speed is automatically selected. CONSTITUTION:The equipment is provided with a dial notice means 121, a connection discrimination means 122, a speed discrimination means 123 and a redial command means 124, and whether or not the connection with an opposite station is enabled is discriminated based on return information from a network 11 in reply with the dialing. When the connection is disable, whether or not the disable connection depends on the speed dissidence is discriminated based on a reason of disable connection. When the disable connection is due to the dissident speed, the communication speed is selected to make redialing and when the disable connection is not due to the dissident speed, redialing is implemented at a current communication speed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication device that is connected to a circuit-switched network and is capable of switching communication speeds.

[0002] In recent years, in the field of communications, communication services using an integrated service digital network (hereinafter referred to as "ISDN"), which transmits various media over a single digitized network, are being put into practical use.

[0003] In ISDN, communication is possible in packet switching mode and circuit switching mode.

[0004] In the packet switching mode, the communication speed is managed by the network exchange, so communication can be performed even if the communication speeds of the originating side and the receiving side are different.

On the other hand, in circuit switching mode,
Communication speeds are managed by communication devices connected to the network, so if the communication speeds of the calling and receiving sides differ,
Unable to communicate.

[0006] Therefore, when communicating in the ISDN circuit switching mode, it is necessary to match the communication speeds of the calling and receiving sides.

However, in the international ISDN that connects stations installed around the world, the communication speed in Japan and Europe is currently set at 64 Kbps, and the communication speed in North America is set at 56 Kbps.

[0008] Therefore, using the international ISDN, Japan (
When communicating between Europe (or Europe) and North America, a communication speed switching function is required.

[0009] In this case, it is necessary to switch the communication speed in Japan (or Europe) whether the call is originating from Japan (or Europe) or incoming from Japan (or Europe).

[0010] This increases the communication speed from 64Kbps to 56Kbps.
This is because if the data amount is to be lowered to Kbps, the data amount can be substantially reduced to 56 Kbps by inserting dummy bits, but in the opposite case, such a method cannot be used.

[Conventional technology]

Conventionally, when Japan makes a call, the communication speed has to be changed manually.

However, with this configuration, there is a problem in that when the destination station is in North America, the operator's operations at the time of making a call become complicated.

[0013] In other words, in the international ISDN, since the partner stations are scattered all over the world, the operator generally
In many cases, the location of the other station, or in other words, the communication speed of the other station, is not known.

[0014] Therefore, if Japan is the sender,
For now, it is necessary to make a call with the declared speed (the communication speed of the local station declared at the time of the call) being 64 Kbps.

However, in this case, if the partner station is in North America, as shown in FIG.
The communication was rejected by the exchange (called ``KDD'').

[0016] In this case, the declared speed is set to 64.
It is necessary to switch from Kbps to 56 Kbps and perform a re-call.

[0017] Conventionally, however, the communication speed has been manually switched, and as a result, the operator has to perform the calling operation twice.

Note that this problem can be solved by preparing a memo in which the communication speed of each station is recorded in advance.

However, even in this case, the operator has to read the memo every time he or she makes a call, which still makes the operation at the time of making a call complicated.

[0020]

[Problems to be Solved by the Invention] As mentioned above, conventionally, when Japan makes a call using the international ISDN, the communication speed has to be changed manually, which makes the operator's operations complicated when making a call. There was a problem with becoming.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a communication device that can improve operability for an operator when making a call by automatically switching the communication speed.

[0022]

[Means for Solving the Problems] FIG. 1 is a block diagram showing the basic configuration of a first invention.

In FIG. 1, in response to a call originating from a calling station, 11 returns information indicating whether or not the calling station and the receiving station are connectable, and if the calling station is not connectable, This is a circuit-switched network that returns this information along with the reason for connection failure.

Reference numeral 12 denotes a communication device connected to this network 11 and capable of switching communication speeds.

In this communication device 12, numeral 121 is a call notification means that, upon receiving an instruction to make a call, notifies the network 11 of the call using the currently set communication speed as the declared speed.

Reference numeral 122 denotes connection determining means for determining whether or not the local station and the other station can be connected based on the return information sent from the network 11 in response to the call originating from the call notification means 121. It is.

When the connection determination means 122 determines that connection is not possible, 123 determines whether the connection failure is due to a mismatch in communication speed between the own station and the other station, based on the reason for connection failure included in the returned information. This is a speed determining means for determining whether

When the speed determining means 123 determines that the connection failure is due to a speed mismatch, the 124 switches the communication speed and instructs the call notification means 121 to make a re-call using the newly set communication speed. If it is determined that this is not due to a speed mismatch, the re-call instructing means instructs the call notification means 121 to re-call at the currently set communication speed.

FIG. 2 is a block diagram showing the basic configuration of the second invention.

In the figure, when a speed confirmation request is received from a first station, 15 determines whether the communication speeds of this first station and a second station with which this first station desires to connect match or not. This is a circuit-switched network that determines the determination result and returns the determination result to the first station.

Reference numeral 16 denotes a communication device installed at the first station and capable of switching communication speed.

In this communication device 16, each time the communication speed of the own station is switched, the communication device 161 notifies the network of a speed confirmation request including the identification information of the station desiring connection and the identification information of the communication speed of the own station. This is a speed confirmation request notification means.

162 is this speed confirmation request notification means 16
1 to the network 15, the speed at which it is determined whether the communication speeds of the own station and the connection requesting station match, based on the determination result returned from the network 15. It is a means of judgment.

Reference numeral 163 denotes a speed switching means that switches the communication speed of its own station when the speed determining means 162 determines that the communication speeds do not match.

[0035]

In the first aspect of the invention, as shown in FIG. 3, first, the call notification means 121 notifies the network 11 of the call using a preset communication speed as the declared speed. (Step S1).

Next, the connection determining means 122 determines whether or not the local station and the other station can be connected based on the return information sent from the network 11 (step S2).
, if it is determined that connection is possible, data transfer is executed at the declared speed (step S3).

On the other hand, if it is determined that the connection is not possible, the speed determination means 123 determines whether the connection failure is due to a mismatch in the communication speed between the own station and the other station, based on the reason for the connection failure included in the returned information. is determined (step S4).

If it is determined by this determination process that the connection failure is due to speed mismatch, the re-call instructing means 124 switches the communication speed (step S5) and then instructs re-call. As a result, the process returns to step S1, and a re-call is executed at the newly set communication speed.

On the other hand, if it is determined that the connection failure is not due to a speed mismatch, a re-call is instructed at the current communication speed. As a result, the call is made again at the same communication speed.

[0040] By repeating the above operations, even if the communication speeds of the local station and the other station are different, the communication speeds of both stations will eventually be matched, and moreover, the local station and the other station will be able to connect. If there is, data transfer in step S3 is executed.

From the above, according to the first invention, even if the communication speeds of the own station and the other station are different, the operator only needs to perform the calling operation once when starting the call. The operator's operability when making a call can be improved.

[0042] In the second invention, as in the first invention, the communication speed of the own station is automatically adjusted to the communication speed of the station to which connection is desired.

Furthermore, in this case, speed switching is performed based on a speed confirmation operation rather than a call origination operation. Therefore, before making an actual call, if you check the speed of all stations with which you may communicate, and register this check result in memory, etc., when making an actual call, you can Communication is possible simply by inputting the station's identification information.

[0044]

Embodiments Hereinafter, embodiments of the first and second inventions will be described in detail with reference to the drawings.

FIG. 4 is a block diagram showing the configuration of a first embodiment of the first invention, which is characterized in that speed switching is performed when making a call.

[0046] In the following explanation, as a communication device,
The first invention will be explained using a representative facsimile terminal connected to an international ISDN in Japan.

[0047] In the figure, 21 is a communication unit that transmits and receives data. Reference numeral 22 denotes an input/output unit that reads the original and prints on recording paper. 23 is a signal processing unit that processes transmission data and reception data.

Reference numeral 24 denotes a control section that controls each section of the apparatus. Reference numeral 25 denotes an operation unit for an operator to operate the device. 26 is a display unit that displays the status of the device and the like.

In the communication section 21, 211 is a communication control section that is connected to the network and executes transmission and reception operations. 212 is a speed conversion circuit that converts the communication speed.

In the input/output unit 22, 221 is a scanner that reads characters, etc. from a document. 222 is a reading control circuit that controls the reading operation of this scanner 221. 223 is a printer that records characters and the like on recording paper. 224 is a recording control circuit that controls the recording operation of this printer 223.

In the signal processing circuit 23, 231 is a compression/decompression circuit that encodes transmission data and decodes reception data. 232 is a file memory that temporarily holds encoded transmission data and reception data. 233 is a read-only memory (hereinafter referred to as "ROM") that stores image data corresponding to the code. 234 is a CG expansion circuit that accesses this ROM 233.

In the control unit 24, 241 is a microprocessor unit (hereinafter referred to as
(referred to as "MPU"). 242 is this MPU24
This is a ROM that stores a program that controls the operation of the computer. Reference numeral 243 denotes a memory that can be written and read at any time (hereinafter referred to as "RAM") used as a working memory of the MPU 241. 244 is a data table RAM for storing abbreviated numbers and the like.

In the operation section 25, 251 is a keyboard for the operator to operate the device. 25
Reference numeral 2 denotes a key input control circuit that controls key input on this keyboard 251.

In the display section 26, 261 is a liquid crystal display section (LCD) that displays the status of the apparatus and the like. 26
2 is a display control circuit that controls the display operation of this liquid crystal display section 261.

In the above configuration, the read output of the scanner 221 is encoded by the compression/decompression circuit 231, and then
It is sent from the communication control unit 211 to the other party's station via the network.

On the other hand, the data sent from the other station is
After being decoded by the compression/decompression circuit 231, the printer 2
23 is recorded on the recording paper.

[0057] In this case, if the partner station is located in North America, the communication speed is 56.
Kbps. On the other hand, if the other party's station is in Japan or Europe, the speed is set to 64 Kbps regardless of whether the call is originating or receiving.

This setting is made in the speed conversion circuit 212. The operation of the speed conversion circuit 212 is controlled by the MPU 241 based on a program stored in the program ROM 242, which will be described in detail later.

FIG. 5 is a diagram showing the control functions of the MPU 241 in FIG. 4 in blocks.

In the figure, reference numeral 31 denotes a line control section that controls communication operations of the communication control section 211. 32 is a speed switching determination unit that determines whether or not to switch the communication speed. Reference numeral 33 denotes a line switching speed switching control section that controls switching of the communication speed based on the determination result of the speed switching determination section 32.

Reference numeral 34 denotes a reading/recording control section that controls the operations of the reading control circuit 222 and the recording control circuit 224. 35
is a data compression/decompression control unit that controls the operation of the compression/decompression circuit 231. 36 is an image data transfer control unit that controls image data transfer.

The configuration of the first embodiment of the first invention has been described above. Next, the automatic communication speed switching process when a call is made from Japan, which is a feature of the first invention, will be described.

FIG. 6 is a flowchart schematically showing the automatic speed switching process according to the first embodiment of the first invention.

As shown in the figure, in this embodiment, a call is first made with a declared speed of 64 Kbps (step S11). Next, based on the information returned from the network in response to this call, it is determined whether or not it is possible to connect to the partner station (step S12).

If connection is possible, data transfer is performed at 64 Kbps (step 13). On the other hand, if the connection is not possible, it is determined whether the returned information includes the reason for the connection failure (step S14).

If the connection failure reason is not included, the communication speed is switched to 56 Kbps, and a re-call is made at this speed (step S16). On the other hand, if the connection failure reason is included, it is determined based on the connection failure reason whether or not the connection failure is due to speed mismatch (step S15).

If the connection failure is due to speed mismatch, the communication speed is switched to 56 Kbps, and a re-call is made at this speed (step S16). On the other hand, if it is not due to a speed mismatch, the process returns to step S11 and a call is made again with the declared speed of 64 Kbps.

Similarly, when calling at 56 Kbps,
It is determined whether connection is possible (step S17). If the connection is possible, data transfer is performed at 56 Kbps (step S18), and if the connection is not possible, the process returns to step S11 without determining whether there is a reason for the connection failure or its contents, and a re-call is made at 64 Kbps.

As described above, in this embodiment, a call is initially made at 64 Kbps, and if the speeds do not match, the communication speed is switched to 56 Kbps and a call is made again.

[0070] At the time of this switching, based on the reason for the connection failure,
The reason why it is determined whether the connection failure is due to a speed mismatch is as follows.

That is, whether or not the communication speeds match can be basically determined by determining whether or not the local station and the other station can be connected based on information returned from the network.

However, in reality, even if the communication speeds match, connection may become impossible because the other party is busy, for example. In such a case, it is preferable to call again at 64 Kbps without changing the communication speed.

Therefore, in this embodiment, even if it is determined that connection is not possible, the communication speed is not switched immediately, but based on the reason for connection failure, it is determined whether or not the connection failure is due to speed mismatch. It is designed to be judged.

[0074]The communication speed is switched only when the speed mismatch occurs, and when the speed mismatch is not the case, the call is made again at 64 Kbps.

[0075] As a result, even if the communication speeds match but connection becomes impossible due to a busy conversation,
Since the communication speed is not switched, the call setup time from the start of the calling process to the completion of the connection can be shortened.

The reason why the presence or absence of a reason for connection failure is determined when determining whether or not the connection failure is due to speed mismatch is as follows.

That is, if the network is ISDN, the reason for the connection failure would normally be sent back from this network to the originating station.

However, for example, if a private branch exchange (hereinafter referred to as "PBX") exists in the network, this P
BX may omit the reason for connection failure.

[0079] If the reason for connection failure is omitted, it becomes impossible to determine whether or not the connection failure is due to speed mismatch, making it impossible to proceed with subsequent processing.

Therefore, in this embodiment, a step S14 is provided to determine whether or not there is a reason for connection failure, and if the returned information does not include a reason for connection failure, it is assumed that the connection failure is due to speed mismatch, After that, the process can proceed.

[0081] Furthermore, the reason why the presence or absence of a reason for connection failure and its contents are not determined when making a 56 Kbps call is as follows.

[0082] In other words, assuming that the reason for connection failure is eliminated by the PBX, even if the connection failure during 64Kbps transmission is not due to speed mismatch,
The communication speed can be switched from 64Kbps to 56Kbps.

[0083] Even in such a case, 64Kbps
There is no problem if the transmission frequency of 56Kbps and 56Kbps is almost the same.

However, in the international ISDN, not only international communication but also domestic communication is possible. This domestic communication is performed at 64 Kbps. Therefore, when comparing the transmission frequencies of 64 Kbps and 56 Kbps, the former is generally higher.

In such a case, the average call setup time can be shortened by allocating more time to the 64 Kbps call processing.

Therefore, in this embodiment, if it is determined that connection is not possible when making a call at 56 Kbps, the call is made again at 64 Kbps without determining the presence or absence of the reason for connection failure or its contents. .

The automatic speed switching process of the first embodiment has been briefly described above. Next, this automatic speed switching process will be specifically described with reference to FIGS. 7 to 9.

FIG. 7 is a flowchart showing the overall flow of automatic speed switching processing.

In this automatic speed switching process, first,
Number of redials A when connection is not possible for retransmission counter
is set (step S21). This redial number A is appropriately set in advance.

When the number of redials A has been set, the flag is set to "0" (step S22). This flag is used to determine whether to switch from 64 Kbps transmission processing to 56 Kbps transmission processing.

[0091] That is, if the content of this flag remains "0", switching from 64 Kbps to 56 Kbps is performed, and if it is rewritten from "0" to "1", this switching is not performed. .

[0092] After setting the flag, 64 Kbps transmission processing is performed (step S23). In this calling process, as described above, if it is determined that connection is possible, data transfer is executed. In this case, the content of the retransmission counter is rewritten from "A" to "1". Further, the contents of the flag are rewritten from "0" to "1".

On the other hand, if it is determined that the connection is not possible, the presence or absence of the reason for the connection failure and its contents are determined. As a result of this determination, if it is determined that there is a reason for the connection failure and that the connection failure is not due to speed mismatch, the flag is rewritten from "0" to "1".

On the other hand, if there is no reason for connection failure or if connection failure is due to speed mismatch, the content of the flag is ``
It is fixed at 0.

[0095] When the 64 Kbps transmission process is completed, it is determined whether the content of the flag is "0" (step S24).
. If the content of the flag is "0", 56 Kbps transmission processing is performed (step S25), and if it is "1", the content of the retransmission counter is decremented by 1 (step S26).

[0096] Therefore, in the 64 Kbps outgoing process, if it is determined that the connection is not possible, and it is determined that there is no reason for the inability to connect, or if it is determined that the inability to connect is due to a speed mismatch, the 56 Kbps outgoing process is performed. Ru.

On the other hand, if it is determined that connection is possible (data transfer has been performed) or if it is determined that connection failure is not due to speed mismatch, the retransmission counter is decremented.

In the 56 Kbps transmission process, if it is determined that connection is possible, 56 Kbps data transfer is executed as described above. In this case, the content of the retransmission counter is rewritten from "A" to "1". On the other hand, if it is determined that connection is not possible, nothing is done and the calling process ends.

When the 56 Kbps transmission process is completed, the contents of the retransmission counter are decremented by 1 (step S26). Thereafter, it is determined whether the content of the retransmission counter is "0" (step S27).

[0100] If the content of the retransmission counter is "0", the calling process ends. On the other hand, if it is not "0", a redial waiting time a (minutes) is set in the timer, and when this waiting time a has elapsed, the above-mentioned processing is executed again from step S22 (steps S28, S29). )
.

[0101] Therefore, 64Kbps transmission processing and 5Kbps transmission processing
In the 6 Kbps outgoing call process, if data transfer is performed, the outgoing call process ends without redialing.

[0102] Also, in the 64 Kbps transmission process,
If it is determined that the connection failure is not due to a speed mismatch, or if it is determined that the connection is impossible in the 56Kbps call processing, redial is executed from 64Kbps.

By executing the above operations, even if the communication speeds of the own station and the other station are different, the communication speed of the own station is finally matched to the communication speed of the other station. At this time, if the connection is possible, data transfer is executed, and if the connection is not possible even after repeated redials, the calling process ends.

FIGS. 8 and 9 show the 64Kbp in FIG.
2 is a flowchart specifically showing the transmission process of s.

In this transmission process, first, as shown in FIG. 8, the declared speed is 64 Kbps to the network.
The call is notified (step S31).

[0106] This call notification is executed using a call setup message. This call setup message includes a calling signal for transmitting the call to the network, a station identification parameter for identifying the other station, a speed identification parameter for identifying the declared speed of the own station, etc. .

[0107] Here, the partner station is designated by the operator. On the other hand, the declared speed is set in advance to 64 Kbps.

Next, it is monitored whether or not signal data is sent from the network (step S32), and when signal data is sent, the content of this received data is determined (steps S33 to S36). This determines whether or not it is possible to connect to the other station.

That is, if the received data is a response message, it is determined that connection is possible, and if the received data is any one of a release completion message, a release message, and a disconnection message, it is determined that connection is impossible.

[0110] If the received data is not any of these return messages, the process returns to step S32 and again,
Receipt of signal data is monitored.

[0111] In the ISDN call control sequence, basically, if connection is possible, a response message is returned, and if connection is not possible, a disconnection message is returned.

[0112] Therefore, basically, it is possible to determine whether connection is possible or not by determining whether the received data is a response message or a disconnection message.

However, the above-described call control sequence is not fixed, and certain modified specifications are allowed. In other words, when connection is not possible, it is permitted to send back a release completion message or a release message instead of a disconnection message.

Therefore, in this embodiment, when it is determined that the received data is not a response message, the call control sequence is executed by sequentially determining whether the received data is a release completion message, a release message, or a disconnection message. It is designed to handle modified specifications.

[0115] If it is determined that the received data is a response message, 64 Kbps data transfer processing is executed (steps S37, S38).

When this data transfer process is completed, the content of the retransmission counter is rewritten from "A" to "1" (step S39).

[0117] After this rewriting is completed, call release processing is performed. (Steps S40-44). In this call release process, first, a disconnection message indicating that the data transfer of the local station has been completed is sent to the network (step S4).
0).

Next, it is determined whether signal data has been sent from the network (step S41), and if signal data has been sent, its contents are determined (steps S42, S43).

[0119] If the received data is a release message indicating the end of the data transfer of the other station, a release completion message indicating the release of the call of the own station is sent back to the network (step S44). This completes the call release process.

On the other hand, if the received data is a release completion message indicating release of the other station's call, the call release process ends as is.

[0121] The reason why it is determined not only whether the received data is a release message but also whether it is a release completion message is that, as described above, certain modification specifications are allowed for the call control sequence.

That is, in ISDN, basically, a release message is sent in response to a disconnection message.

However, even in this case, as an exception, it is permitted to send back a release completion message instead of a release message.

Therefore, in this embodiment, after transmitting the disconnection message, it is sequentially determined whether the received data is a release message or a release completion message.

[0125] When the call release process is completed, the contents of the flag are rewritten from "0" to "1" (step S45).
). When this process is completed, the 64 Kbps transmission process when connection is possible is completed.

Note that by rewriting the flag from "0" to "1", the 56 Kbps transmission process is not performed as described above. Also, the content of the retransmission counter is "A".
By rewriting the value from "1" to "1", the outgoing call process ends without redialing being executed.

If it is determined in step S33 that the received data is not a response message, it is determined whether the received data is a release completion message (step S34).

When it is determined that the received data is a release completion message, as shown in FIG. 9, it is determined whether there is a reason for the connection failure and whether or not the connection failure is due to a speed mismatch. (Steps S46, S47).

The presence or absence of a connection failure reason is determined by determining whether or not the release completion message includes a reason display parameter (step S46).

That is, if the reason display parameter is included, it is determined that there is a reason for not being able to connect, and if it is not included, it is determined that there is no reason for not being able to connect.

[0131] Whether or not the connection failure is due to speed mismatch is determined by determining whether the reason display parameter is a parameter that indicates "transmission capability not permitted" (step S48).

That is, if the reason display parameter is a parameter that indicates "transmission ability not permitted," it is determined that the cause is due to speed mismatch, and if it is any other parameter, it is determined that the cause is not due to speed mismatch.

[0133] If there is no reason display parameter, or if the reason display parameter is a parameter "transmission ability not permitted", the flag is fixed to "0" (step S
47). As a result, in this case, 56 Kbps transmission processing is performed.

On the other hand, if the reason display parameter is a parameter other than the parameter "transmission ability not permitted", the flag is rewritten from "0" to "1" (step S49). This results in 56K in this case.
No bps transmission processing is performed.

[0135] This flag rewriting process (step S48,
Upon completion of step S49), the 64 Kbps transmission process ends (step S62).

Although details are omitted, step S35
, even if it is determined that the received data is a release message, the connection failure reason determination process (S50, S51
) and flag rewriting processing (S52, S53).

However, in this case, flag rewriting processing (S
52, S53), the call release process is executed by transmitting a release completion message (step S54).

Similarly, if it is determined in step S36 that the received data is a disconnection message, the process of determining the reason for connection failure (S55, S56) and the process of rewriting the flag (S57, S58) are performed.

[0139] Also in this case, call release processing is performed by transmitting a release message and receiving a release completion message (S60, S61).

FIG. 10 is a flowchart specifically showing the 56 Kbps transmission process.

[0141] Also in this 56 Kbps transmission process,
Similar to the 64 Kbps origination process described above, first, a call setup message is transmitted (step S71), and then reception of signal data in response to this call setup message is monitored (step S72).

[0142] If there is received data, it is determined whether or not connection is possible by determining its contents (step S
73-S76).

If connection is possible, 56 Kbps data transfer processing (steps S77, S78), retransmission counter rewriting processing (step S79), and call release processing (steps S80 to S84) are sequentially executed.

[0144] Thereafter, unlike the 64 Kbps transmission process, the transmission process is ended without rewriting the flag (step S89).

[0145] The reason why the flag is not rewritten is that this flag changes the 64Kbps transmission processing to 56Kbps as described above.
This is because it is used to determine whether to switch to bps transmission processing.

On the other hand, if the connection is not possible, the call is released without determining the reason for the connection failure or rewriting the flag (steps S85 to S88).

The above is the specific content of the automatic speed switching process. Next, this automatic speed switching process will be explained using a call control sequence.

FIG. 11 is a diagram showing a call control sequence when calling from Japan to Japan.

[0149] In this case, first, call setting processing is performed. In this call setting process, first, a call setting message is sent from the calling side to the Advanced Information and Communication System Network (hereinafter referred to as the "INS network"). In this case, the declared speed is set to 64 Kbps. Here, the INS network is a domestic network based on ISDN.

[0150] The call setup message sent to the INS network is
Furthermore, it is sent from this INS network to the called party. When the called party responds to this call setup message, the called party sends a response message back to the INS network.

[0151] The response message sent to the INS network is further sent back from this INS network to the called party. At the same time, a response confirmation message is sent back from the INS network to the calling party.

[0152] This completes the call setting process. After this, data transfer at 64 Kbps is performed between the calling side and the called side.

[0153] When this data transfer is completed, call release processing is performed. In this call release process, first, a disconnection message is sent from the originating side to the INS network indicating that the data transfer on the originating side has been completed. This disconnection message is further sent from the INS network to the called party.

[0154] When the called side receives the disconnection message, the called side returns a release message to the INS network to notify that the data transfer on the called side has been completed. This release message is further sent back from the INS network to the originating party.

[0155] Thereafter, a release completion message is sent from the calling side to the INS network to notify that the release of the call has been completed. This release completion message further includes:
Sent from the INS network to the called party. This completes the call release process.

FIG. 12 is a diagram showing a call control sequence when calling from Japan to North America.

[0157] In this case as well, first, a call setup message with a declared speed of 64 Kbps is sent from the originating side to the INS network. This call setup message further includes the IN
It is sent from the S network to the KDD switch.

[0158] When this exchange receives a call setting message, it is determined whether the communication speeds of the calling side and the called side match based on the station identification parameter and speed identification parameter included in the call setting message. Ru.

[0159] In the present example, the called party is in North America, and the communication speed in North America is 56 Kbps, so it is determined that the speeds do not match.

[0160] As a result, in this case, the call setting process is interrupted and the call release process is performed. This call release process is basically the same as the call release process in FIG. 11 described above.
This is done using disconnect messages, release messages, and release completion messages.

[0161] However, in the call release process in this case,
First, a call release process is performed between the KDD and the INS network, and then a call release process is performed between the INS network and the originating side.

[0162] Furthermore, a reason indicating parameter "transmission ability not permitted" is inserted in the disconnection message. This allows the calling party to determine that the connection failure is due to speed mismatch.

[0163] When the calling side determines that the connection failure is due to a speed mismatch, the calling side sends a call setup message with a declared speed of 56 Kbps to the INS.
sent to the net.

[0164] This call setup message is sent from the INS network to the K
Sent to the DD exchange. As a result, a determination result that the communication speeds match is obtained this time.

[0165] As a result, an incoming call message is sent from this exchange to the called party. When the called party responds to this incoming call message, the called party sends an incoming call acceptance message back to the KDD exchange.

[0166] When the KDD exchange receives the call acceptance message, the exchange sends a response message back to the INS network. This response message further includes I
Sent from the NS network to the calling side.

[0167] This completes the call setting process. Thereafter, data is transferred at 56 Kbps between the calling side and the called side.

[0168] When this data transfer is completed, call release processing is performed. This call release processing is basically performed between the calling side and the INS network and between the INS network and the KDD exchange using a disconnection message, a release message, and a release completion message.

On the other hand, a disconnection instruction message and a disconnection confirmation message are used between the KDD exchange and the called side.

[0170] The automatic speed switching process when Japan is the calling party has been described above. Next, for reference, automatic speed switching processing when Japan is the receiving party will be explained.

FIGS. 13 and 14 are flowcharts showing automatic speed switching processing when Japan is the receiving party.

[0172] In this automatic speed switching process upon incoming call, first, as shown in Fig. 13, reception of a call setting message is monitored (steps S91, S92).

[0173] Upon receiving the call setup message, the declared speed of the caller is determined (step S93). This determination is made based on the speed identification parameter included in the call setup message.

[0174] If the declared speed is 56 Kbps, after the response message is transmitted, reception of a response confirmation message to this response message is monitored (steps S94 to S96).

[0175] When the response confirmation message is received, the communication speed is switched to 56 Kbps, and data transfer is executed at this 56 Kbps (steps S97 and S98).

[0176] Even when the declared speed is 64 Kbps, the call setting process (steps S99 to S101) is performed in the same way.
), data transfer processing (S102, S103) is performed.

[0177] However, in this case, the communication speed is set to 64K in advance.
Since the communication speed is set to bps, the communication speed switching process is not executed.

[0178] When the data transfer processing is completed, call release processing is performed as shown in Fig. 14 (step S105).
~S111). Although the details of this call release process are omitted,
It is possible to handle modified specifications of call control sequences.

[0179] When this call release process is completed, the incoming call process ends.

According to this embodiment described in detail above, the following effects are achieved.

(1) The operator's operability when making a call can be improved.

[0182] When it is determined that connection is not possible when making a call, it is determined whether the connection failure is due to speed mismatch based on the reason for connection failure, and based on this determination result, a predetermined This is because by executing the re-call, the operator only needs to perform the calling operation at the time of starting the call.

(2) Even though the communication speed of the other station is 64 Kbps, the call setup time can be shortened when connection becomes impossible due to a busy call or the like.

[0184] This determines whether the communication speeds match or differ not only by whether or not connection is possible, but also by the reason for connection failure, and if the connection failure is not due to speed mismatch, 56K
This is because redialing is performed at 64 Kbps without executing bps transmission processing.

(3) Even if the reason for connection failure is deleted by a PBX or the like, processing can proceed.

[0186] This is because if there is no reason for connection failure, it is assumed that there is a speed mismatch and the subsequent processing is proceeded.

(4) The transmission frequency of 64Kbps is 56
It is possible to execute speed switching processing that takes into account the fact that the transmission frequency is higher than the transmission frequency of Kbps.

[0188] This means that if it is determined that connection is not possible during 56Kbps transmission processing, the process shifts to 64Kbps transmission processing without determining whether or not there is a reason for connection failure or its contents, so that 64Kbps transmission, which has a high frequency of transmission, is This is because more time is allocated to the transmission process.

FIG. 15 is a flowchart showing automatic speed switching processing according to the second embodiment of the first invention. Note that in FIG. 15, the same steps as those in FIG. 6 are given the same reference numerals, and detailed description thereof will be omitted.

[0190] In the above embodiment, if it is determined that connection is not possible in the 56 Kbps transmission process, 64 Kbps is
The case of redialing with s has been explained.

[0191] As mentioned above, when Japan is the sending side, the sending frequency of 64 Kbps is generally higher than 56 Kbps.
This is because we focused on the fact that the transmission frequency is higher than that of bps.

However, depending on the nature of the station, the frequency of transmission may be almost the same.

Therefore, in this embodiment, even in the 56 Kbps transmission process, the presence or absence of a reason for connection failure and its contents are determined.

In the figure, S121 is a step for determining whether there is a reason for connection failure when transmitting at 56 Kbps, and S122 is a step for determining whether or not the connection failure is due to speed mismatch.

In such a configuration, if it is determined that there is no reason for connection failure, 64 Kbps redial is executed. On the other hand, if it is determined that the connection failure is not due to a speed mismatch, 56 Kbps redial is executed, and if it is determined that the connection failure is due to a speed mismatch, the calling process is terminated.

[0196] Therefore, 64Kbps and 56Kbps
It is possible to implement processing that takes into account the fact that the transmission frequencies of the two are almost the same.

FIG. 16 is a flowchart showing automatic speed switching processing according to the third embodiment of the first invention. Note that in FIG. 16, steps that are the same as in FIG. 6 are given the same reference numerals, and detailed explanations will be omitted.

[0198] In the first and second embodiments described above, the case where automatic speed switching processing is performed every time a call is made has been described.

On the other hand, in this embodiment, the speed automatic switching process is performed only at the first call, and the communication speed of the partner station confirmed by this process is registered in the memory, etc., and from the second call onwards, , the call is made based on this registered communication speed.

[0200] That is, in this embodiment, FIG.
As shown in, for example, data transfer steps S13, S
After step 18, registration steps S133 and S134 are provided.

[0201] In the registration steps S133 and S134, when the data transfer is completed, the communication speed for this data transfer is registered in a memory to which a storage area is allocated for each station.

[0202] Furthermore, upon this registration, registration determination data indicating whether or not the registration has been completed is also registered. This registration determination data is read out at the start of a call and is used to determine whether registration of communication speed has been completed (step S13).
1).

[0203] If the communication speed is registered, the outgoing call process is performed at this registered speed (step S132), and if it is not registered, the automatic speed switching process as explained in FIG. 6 is performed.

Note that, as a memory for registering communication speed and registration determination data, for example, the data table RAM 244 shown in FIG. 4 can be used.

[0205] According to such a configuration, there is no need to perform speed automatic switching processing from the second call onward.
From the first call onward, the call setup time can be shortened.

[0206] Also, step S133 is changed to step S13.
The reliability of 64 Kbps registration can be improved by providing it after .

[0207] In other words, in addition to the above-mentioned timing, the timing for registering 64 Kbps may be, for example, the timing when it is determined in step S15 that the connection failure is not due to speed mismatch.

However, if the determination in step S15 is incorrect for some reason, the registered contents will also be incorrect.

[0209] On the other hand, if step S133 is provided after step S13, the registration of 64 Kbps will be executed after the data transfer is actually executed, so that the registered contents will not be incorrect. .

FIG. 17 is a flowchart showing automatic speed switching processing according to the fourth embodiment of the first invention.

[0211] In the third embodiment, at the time of the first call,
The case of registering the communication speed of the other station has been explained.

However, in such a configuration, the communication speed cannot be registered unless a call request actually occurs.

In contrast, in this embodiment, the communication speed can be registered in advance before the actual outgoing call.

To achieve this objective, this embodiment, as shown in FIG.
18, delete S131, S132, and step S133
, S134, a call release processing step (step S14
1, S142).

[0215] According to such a configuration, as in the third embodiment, although the configuration utilizes the call notification function,
The communication speed of the other station can be registered in advance before the actual call.

FIG. 18 shows the first aspect of the second invention, which is characterized in that automatic speed switching processing is performed based on a speed confirmation request.
2 is a flowchart illustrating automatic speed switching processing according to the embodiment.

[0217] In the embodiment shown in Fig. 17, a case was explained in which the communication speed of the other station is registered in advance prior to the actual outgoing call, but this is only a case where the registration is executed using the calling function. It was something.

On the other hand, in this embodiment, the communication speed of the other station is registered in advance prior to making a call by performing automatic speed switching processing based on the speed confirmation request.

That is, in this speed automatic switching process, first, a speed confirmation message is sent to the network (step S151). This speed confirmation message includes a station identification parameter for identifying the station to which the own station wishes to connect (hereinafter referred to as the "desired station") and a speed identification parameter for identifying the communication speed of the own station. It will be done.

[0220] Upon receiving the speed confirmation request message, the network determines whether the communication speeds of the confirmation requesting station and the connection requesting station match based on the station identification parameter and the speed identification parameter. This determination result is sent back from the network to the originating station as a determination message.

[0221] The originating station that sent the speed confirmation message determines whether or not a determination message has been returned from the network (steps S152, S153), and when the determination message is returned, communication is determined based on this determination message. It is determined whether the speeds match (
Step S154).

[0222] If the communication speeds match, this communication speed is registered in the memory (step S155). On the other hand, if the communication speeds do not match, after the communication speeds are switched (step S156), the process returns to step S151,
A speed confirmation message is sent again.

[0223] Thereafter, similar processing is repeated until the communication speeds match, and when the communication speeds match, that speed is registered in the memory.

[0224] By executing the above processing for all stations desiring connection, the registered speed can be used to make the actual call, so automatic speed switching processing becomes unnecessary.

[0225] According to such a configuration, the configuration is simpler than when registering the communication speed using the calling function.
Moreover, registration can be executed in a short time.

Although several embodiments of the first and second inventions have been described above, the first and second inventions are not limited to the embodiments described above.

(1) For example, in the description of the first invention above, the case where the first invention is applied to a communication device connected to a network in which two types of communication speeds coexist was described.

However, the first invention can also be applied to a communication device connected to a network in which three or more types of communication speeds coexist. In this case, the number of speed switching steps may be increased according to the number of communication speeds.

(2) Also, in the description of the first invention above,
A case has been described in which the first invention is applied to a communication device connected to ISDN.

However, the first invention can be applied to communication devices in general that are connected to a network that can return the reason for connection failure in response to a call.

(3) In addition to the above, it goes without saying that the present invention can be modified in various ways without departing from the gist thereof.

[0232]

[Effects of the Invention] As detailed above, according to the present invention,
In an international ISDN, operator operability can be improved when Japan is the originating party.

[Brief explanation of the drawing]

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

FIG. 2 is a block diagram showing the principle configuration of a second invention.

FIG. 3 is a diagram for explaining the operation of FIG. 1;

FIG. 4 is a block diagram showing the configuration of a first embodiment of the first invention.

FIG. 5 is a block diagram showing the control configuration of FIG. 4;

FIG. 6 is a flowchart diagram schematically showing speed automatic switching processing at the time of a call in the first embodiment of the first invention.

FIG. 7 is a flowchart specifically showing the entire speed automatic switching process at the time of a call in the first embodiment of the first invention.

FIG. 8 is a flowchart specifically showing a part of the 64 Kbps transmission process in FIG. 7;

FIG. 9 is a flowchart specifically showing a part of the 64 Kbps transmission process in FIG. 7;

FIG. 10 is a flowchart specifically showing the 56 Kbps transmission process of FIG. 7;

FIG. 11 is a diagram showing a domestic communication call control sequence at the time of origination in the first embodiment of the first invention.

FIG. 12 is a diagram showing an international communication call control sequence at the time of origination in the first embodiment of the first invention.

FIG. 13 is a flowchart showing a part of automatic speed switching processing at the time of incoming call according to the first embodiment of the first invention.

FIG. 14 is a flowchart showing a part of automatic speed switching processing at the time of incoming call according to the first embodiment of the first invention.

FIG. 15 is a flowchart showing automatic speed switching processing at the time of a call in the second embodiment of the first invention.

FIG. 16 is a flowchart showing automatic speed switching processing at the time of a call in the third embodiment of the first invention.

FIG. 17 is a flowchart showing automatic speed switching processing at the time of a call in the fourth embodiment of the first invention.

FIG. 18 is a flowchart showing automatic speed switching processing at the time of a call in the first embodiment of the second invention.

FIG. 19 is a diagram showing conventional speed switching processing.

[Explanation of symbols]

Claims (6)

[Claims] [Claim 1] In response to a call from a calling station, information indicating whether or not the calling station and the receiving station are connectable is returned, and if the calling station is not connectable, this information is When a communication device (12) connected to a circuit-switched network (11) that returns a message including the reason for making a call receives an instruction to make a call, the communication device (12) returns the call with the currently set communication speed as the declared speed. A call notification means (121) notifies the network (11), and in response to a call from the call notification means (121),
connection determination means (12) for determining whether or not the own station and the other station can be connected based on the return information sent from the
2) When the connection determination means (122) determines that connection is not possible, based on the reason for connection failure included in the returned information, the connection failure is due to a mismatch in communication speed between the local station and the partner station. speed determination means (123) for determining whether or not the speed determination means (123)
If it is determined that the connection failure is due to a speed mismatch, the communication speed is switched and the call notification means (121) is instructed to make a re-call using the newly set communication speed, thereby confirming that the connection failure is not due to a speed mismatch. If determined, a re-call instructing means (124) instructs the call-initiating means (121) to re-call at the currently set communication speed;
A communication device comprising: 2. The speed determining means (123) is configured to determine that the connection failure is due to a speed mismatch if the return information does not include the connection failure reason. The communication device according to claim 1. 3. When the current communication speed is a predetermined first communication speed, the speed determination means (123) determines that connection is not possible by the connection determination means (122). 2. The communication device according to claim 1, wherein the communication device is configured to instruct the call notification means (121) to make a re-call at the second communication speed. 4. The apparatus further comprises speed registration means for registering the currently set communication speed as the communication speed of the partner station when the connection determination means (122) determines that connection is possible. The communication device according to claim 1. 5. Upon receiving a speed confirmation request from a first station, it is determined whether the communication speeds of the first station and a second station with which the first station desires to connect match; In a communication device (16) connected to a circuit-switched network (15) that sends this determination result back to the first station, each time the communication speed of the own station is switched, the own station requests connection. a speed confirmation request notifying means (161) for notifying the network of the speed confirmation request including identification information of the station and identification information of the communication speed of the own station; and the speed confirmation request notifying means (161) transmitting the speed speed determination means (for determining whether or not the communication speeds of the own station and the connection requesting station match based on the determination result returned from the network (15) in response to the confirmation request;
162); and speed switching means (163) for switching the communication speed of the local station when the speed determining means (162) determines that the communication speeds do not match. 6. Speed registration means for registering the currently set communication speed as the communication speed of the connection requesting station when the speed determination means (162) determines that the communication speeds match. The communication device according to claim 5, characterized in that: