JP2001308925A - Priority control method for network system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a priority control method for a network system by which congestion control is executed in the Internet according to the priority set for each extension terminal accommodated in an exchange. SOLUTION: The priority control method of this invention adopts an exchange 13 accommodating extension terminals 11 and 12, an IP network 16 and a connector 17. When the extension terminal 11 sets up a call via the IP network 16, the exchange 13 informs the connector 17 about a priority class corresponding to the extension terminal 11. The connector 17 acquires a service type corresponding to the informed priority class and stores it as the service type. After setting up, the connector 17 transmits a voice packet to which the stored service type is set to the Internet 16. The Internet 16 executes priority control on the basis of the service type set to the voice packet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to the Internet,
The present invention relates to a priority control method of a network system for realizing communication such as voice via an IP (Internet protocol) network such as an intranet.

[0002]

2. Description of the Related Art With the recent progress of network technology,
The integration of voice and data networks is rapidly evolving. VoIP that relays a conventional telephone network over an IP network such as the Internet as one of integrated networks
There is a (Voice Over IP) network system (VoIP system).

Conventionally, on the Internet, in order to realize QoS (Quality of Service) requested by a user, a priority according to the user's request is assigned, and a service according to the priority is provided.

[0004] For example, when congestion occurs on the Internet, packet loss or delay occurs, and voice quality deteriorates. For this reason, congestion control is performed on the Internet. As one of the congestion controls, priority control according to the priority is executed.

[0005] That is, according to the priority of the user, the transmission order of the packets is changed in the order of higher priority, or the packet of lower priority is discarded. In addition, transmission of low priority packets to the Internet is suppressed. By such priority control, stable communication quality is provided to a user with high priority (requesting high voice quality).

FIG. 20 is an explanatory diagram showing an example of a conventional VoIP system. As shown in FIG.
In the P system, for example, an exchange (circuit switching network) accommodating a plurality of extension terminals (extension A and extension B) is connected to the Internet via an Internet connection device (IP gateway) 1 and a plurality of extension terminals ( The Internet connection device 2 accommodating the extension C and the extension D) is connected to the Internet.

In order for the VoIP system to execute priority control, each Internet connection device 1 and 2 sets the priority so that a router in the Internet can transmit a packet according to the priority when the Internet is congested. A voice packet containing the indicated header information must be sent to the router.

In the prior art, since the Internet connection device 2 in FIG. 20 directly accommodates the extension C and the extension D, a voice packet (priority in each of the extensions C and D) (FIG. 20) is set. Packet (1)) can be transmitted to the router.

[0009]

However, FIG.
When an exchange is connected to the Internet connection device, as in the Internet connection device 1, the Internet connection device 1 treats the exchange as one extension terminal and does not recognize the extension terminal accommodated in the exchange. .

For this reason, the Internet connection device 1
The voice packet in which the priority of the exchange was set was transmitted to the router (see packet (2) in the figure). Therefore, in the prior art, one extension terminal is accommodated in the exchange.
Only one priority could be set.

As described above, in the prior art, the priority cannot be set for each extension terminal accommodated in the exchange. For this reason, only a low priority can be set to an extension terminal to which a high priority is to be set, and appropriate communication quality may not be provided.

An object of the present invention is to provide a network system in which priority control within an IP network is executed in accordance with a priority set for each terminal accommodated in an exchange, and communication quality according to the priority can be provided. It is to provide a priority control method.

[0013]

The present invention has the following arrangement to solve the above-mentioned problems.

That is, the present invention provides a first exchange accommodating a plurality of first terminals, a first connection device connected to the first exchange, and a second connection connected to the first connection device through an IP network. A connection device, and at least one second terminal connected to the IP network through the second connection device, wherein the first exchange holds a priority class corresponding to each of the first terminals; The connection device holds a service type corresponding to each of the priority classes, and the first exchange establishes a call between an arbitrary first terminal as a calling terminal and a second terminal as a called terminal through an IP network. Is set, the priority class corresponding to the first terminal as the calling terminal is notified to the first connection device,
The first connection device reads a service type corresponding to the notified priority class, saves the read service type, and the first connection device, after the call is established,
When transmitting a packet including data from the first terminal as the originating terminal to the IP network, the stored service type is set so that priority control according to the service type set in the packet is performed in the IP network. This is a priority control method for a network system including setting in a packet.

According to the present invention, the first exchange holds a priority class (priority) for each terminal, and notifies the first connection device of a priority class corresponding to the first terminal as a calling terminal at the time of call setting. After the call setting, the first connection device sets a service type corresponding to the notified priority class in a voice packet transmitted to the IP network. Thereby, priority control corresponding to each terminal accommodated in the exchange is executed in the IP network, and communication quality according to each terminal is ensured.

[0016]

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

<Configuration of VoIP System> FIG. 1 is a configuration diagram showing an example of a VoIP system for implementing a priority control method according to an embodiment of the present invention. In FIG. 1, VoI
The P system uses an extension terminal 11 (extension A as a first terminal).
1) and an exchange 13 accommodating the extension terminal 12 (extension B1)
And an Internet connection device (hereinafter, referred to as an exchange) that connects the exchange 15 accommodating the extension terminal 14 (extension C1) as a second terminal, and the router 22 included in the exchange 13 and the Internet (or intranet) 15 as an IP network. 17, and a connecting device 18 for connecting the exchange 15 and the router 23 included in the Internet 16.

Each of the extension terminals 11, 12, and 14 is, for example, a telephone, a facsimile machine, or a personal computer, a work station, or a mobile computer connected to the exchange 13 via a modem. 11, 12, and 14 are configured using telephone terminals.

Each of the exchanges 13 and 15 is a private branch exchange (PBX) which is one of the circuit exchanges, and each extension terminal (terminal device) accommodated therein has an extension.
(Extension number). Each of the exchanges 13 and 15
Central controller 20 (20a) and main memory (MM) 21
(21a). The exchange 13 is connected to a communication line (in this example, an ISDN (Integrated Service Digital Network).
k)) through the connection device 17.

Each of the connection devices 17 and 18 is a device (gateway device) for connecting another network to the Internet 16 (IP network), and performs a gateway function between them. For example, the connection device 17 in the present embodiment
Implements a function of compressing and encoding voice data transmitted from the ISDN, packetizing the data, and transmitting the packet to the Internet 16, and a function of decoding voice data in a packet received from the Internet 16 and transmitting the data to the ISDN.

<Structure of exchange> Next, each of the exchanges 13, 1
5 will be described. Since the exchanges 13 and 15 have the same configuration, the exchange 13 will be described as an example. FIG. 2 shows the central control unit 2 of the exchange 13 shown in FIG.
0 is a functional block diagram.

As shown in FIG. 2, the exchange 13 executes a call control processing unit 24 (hereinafter referred to as a "call control unit 24") and an ISDN protocol control unit by executing various control programs by the central control unit 20. Unit 25 (hereinafter, referred to as a “protocol control unit 25”), an ISDN message editing processing unit 26 (hereinafter, referred to as an “editing unit 26”), and an ISDN
It functions as a device including a message transmission processing unit 27 (hereinafter, referred to as “transmission unit 27”).

The call control section 24 controls general call control processing of the exchange 13. For example, it manages a process for connecting a call to an extension terminal accommodated in another exchange (exchange 15). The protocol control unit 25 cooperates with the call control unit 24,
Execute the protocol for ISDN. Editing unit 26
Edits a message for controlling a call according to the instruction of the protocol control unit 25. The transmission unit 27
Controls transmission and reception of N messages.

FIG. 3 shows the MM2 of the exchange 13 shown in FIG.
FIG. 4 is a diagram showing the held content of No. 1; As shown in FIG.
21 is memory information 2 required for normal call control processing.
8 and dial number-trunk number conversion table 29 (hereinafter, referred to as
A “conversion table 29” and an extension number corresponding extension attribute data table 30 (hereinafter referred to as “extension attribute data table 3”)
0 ") and a trunk number-corresponding trunk attribute data table 31 (hereinafter," trunk attribute data table 3 ").
1 ”).

FIG. 4 is an explanatory diagram of the dial number-trunk number conversion table 29 shown in FIG. As shown in FIG. 4, the conversion table 29 holds a trunk number or a special priority control number corresponding to a dial number.

FIG. 5 is an explanatory diagram of the extension number corresponding extension attribute data table 30 shown in FIG. As shown in FIG. 5, the extension attribute data table 30 holds extension attribute data corresponding to extension numbers. Extension attribute data
The media type of the extension (voice terminal / FAX terminal / data terminal / image terminal) and the priority class corresponding to the media type are included.

FIG. 6 is an explanatory diagram of the trunk attribute data corresponding to the trunk number shown in FIG. The trunk attribute data table 31 holds trunk attribute data corresponding to a trunk number. The trunk attribute data includes the trunk type (ISDN trunk / Internet connection device /
Analog trunk).

FIGS. 7 and 8 are flowcharts showing the processing in the exchange 13. In FIG.
In the process in S3, the exchange 13 uses the originating terminal (extension terminal 1).
The process starts by receiving the dial number of the receiving terminal (extension terminal 14) from the extension terminal 1 or the extension terminal 12).

First, the call control unit 24 shown in FIG. 2 indexes the conversion table 29 shown in FIG. 4 with the received dial number, and extracts a trunk number corresponding to the dial number (S01).

Next, the call control unit 24 determines whether or not the trunk number has been extracted (S02). At this time, if the trunk number has not been extracted (S02; N), the process proceeds to S03, and if the trunk number has been extracted (S0
In 2; Y), the process proceeds to S06.

When the process proceeds to S03, the call control unit 24 determines whether the received dial number is a special priority control number. At this time, if the dial number is not a special priority control number (S03; N), a conventional connection process is executed (S04), and thereafter, the process in the exchange 13 ends.

On the other hand, if the dial number is a special priority control number (S03; Y), the call control unit 24 sends the index indicating that the dial number is the special priority control number to the protocol control unit 25 as input information. The entry is passed (S05).
Thereafter, the process proceeds to S12 shown in FIG.

On the other hand, when the processing has proceeded to S06, the call control unit 24 executes a trunk acquisition processing. That is, the call control unit 24 indexes the trunk attribute data table 31 shown in FIG. 6 with the trunk number extracted in S01, and reads out the trunk attribute data corresponding to the trunk number (S07).

Next, the call control unit 24 determines whether or not the trunk type included in the read trunk attribute data indicates an Internet connection device (S08). At this time, if the trunk type does not indicate the Internet connection device (S08; N), the conventional connection process is executed (S08).
09) Then, the processing in the exchange 13 ends.

On the other hand, when the trunk type indicates the Internet connection device (S08; Y), the call control unit 24
Index the extension attribute data table 30 shown in FIG. 5 with the extension number of the calling terminal, and read out the extension number attribute data (media type of the extension and priority class corresponding to the media type) corresponding to the extension number (S10). ).

Next, the call control unit 24 passes the entry to the protocol control unit 25 using the index indicating that the dial number is a general call, the read media type, the priority class, and the trunk number as input information. (S11). Thereafter, the processing proceeds to S12 in FIG.

In S12, the protocol control unit 25 shown in FIG. 2 determines what the index is in the input information. At this time, if the index indicates general transmission, the process proceeds to S13; if the index indicates a special priority control number, the process proceeds to S13.
Proceed to 14.

In S13, the protocol control unit 25 passes an entry to the editing unit 26 using the edit message type "call setting message", the media type, the priority class, and the trunk number as input information.

In S14, the protocol control unit 25 passes the entry to the editing unit 26 with the edit message type "INFO message" and the priority class "highest priority" as input information.

In S15, the editing unit 26 shown in FIG.
Identify the edit message type included in the input information. At this time, if the edit message type is “call setup message”, the process proceeds to S16, and if it is “INFO message”, the process proceeds to S17.

In S16, the editing unit 26 edits the call setup message in which the priority class is set in the user / user information, the media type is set in the high-layer compatibility information, and the dial number is set in the called number. Then, the entry is passed to the transmission unit 27.

In S17, the editing unit 26 edits the INFO message in which the priority class “highest priority” is set in the feature indication information, and thereafter, the transmitting unit 27
Pass the entry to.

In S18, the transmitting unit 27 shown in FIG.
The ISDN message (the call setup message or the INFO message) edited in step 16 or S17 is transmitted to the captured trunk (connection device). Thereafter, the processing by the exchange 13 ends.

<Connecting Device> Next, the structure of the connecting devices 17 and 18 shown in FIG. 1 will be described. FIG. 9 is a configuration diagram of each of the connection devices 17 and 18 shown in FIG.

In FIG. 9, the connection device 17 includes a central control device 32, a main storage device (MM) 33, and a first CODEC.
(Speech compression codec) unit 34 and second CODEC unit 3
5 and a communication control device (not shown).

The MM 33 has a priority class correspondence management table 36 (hereinafter, referred to as "management table 36") and a call number correspondence priority class storage data table 37 (hereinafter, referred to as "storage data table 37"). .

The connecting device 18 has substantially the same configuration as the connecting device 17. That is, the connection device includes the central control device 32a, the MM 33a, and the first CODEC unit 34a.
, A second CODEC unit 35a, and a communication control device (not shown). The MM 33a has a management table 36a.
And a stored data table 37a.

The central controller 32 executes various control programs stored in a storage device (not shown) to execute a call connection process between extension terminals via the Internet 16, a voice transmission process, a circuit switching network and an IP network. And the like to realize a gateway function with the server.
The MM 33 holds data used by the CPU 32 and is used as a work area of the CPU 32.

FIG. 10 shows the management table 36 shown in FIG.
FIG. As shown in FIG.
6 holds the service type (priority information) corresponding to the priority class.

FIG. 11 is an explanatory diagram of the stored data table 37 shown in FIG. As shown in FIG. 11, the stored data table 37 stores the service type corresponding to the call number.
(Priority information). The service type stored in each of the tables 36 and 37 is set to a packet (LAN packet, that is, an IP packet) created by the connection device 17 or 18.

The first CODEC unit 34 and the second CODEC
The unit 35 compresses and encodes the voice data received from the exchange 13 and expands and decodes the data field of the voice packet received from the Internet 16.
The first CODEC unit 34 and the second CODEC unit 35 execute a CODEC process according to different standards.

In this example, the first CODEC unit 34
29 Performs CODEC processing according to Annex A (8K CS-ACELP) standards. In G729 Annex A, 80-byte μ Law data is compressed to 10 bytes in 10 millisecond (ms) units.
Stretched. When handling audio data, the audio data is converted to RTP (RF
C1889: Real Time Protocol).

On the other hand, the second CODEC unit 35
CODE according to the standard of 23.1 (6.3K / 5.3K MP-MLQ / ACELP)
Execute the C processing. In G723.1, 240 bytes of μ Law data are compressed / expanded to 24/20 bytes in 30 millisecond (ms) units. When handling audio data, the audio data is transferred as 24-byte packet data according to RTP.

The first CODEC 34 and the second CODEC 34
The DEC unit 35 replaces the above-mentioned CODEC standard with GSM (13K), G
The CODEC process may be executed according to standards such as 711, G722, G726, and G728. Further, each of the connection devices 17 and 18 includes a first CODEC unit 34 and a second
A CODEC unit that executes a CODEC process according to a standard other than the standard set in the CODEC unit 35 may be further provided.

The first CODEC unit 34 and the second CODEC unit
The DEC unit 35 treats a frame that cannot be recognized as speech as silence by the silence compression method. As a result, data corresponding to silence is not transmitted to the Internet 16.
Therefore, traffic on the transmission path can be reduced.
(Generally, 60% of calls are treated as silence). G723
1.1 and G729 Annex B stipulate the principle of silence detection, and each CODEC unit 34 call 35 refers to a flag in the data to determine speech / silence.

<Operation in VoIP System> Next,
The operation in the above-mentioned VoIP system will be described.

(First Operation Example) FIG. 12 is a sequence diagram showing a first operation example in the VoIP system. FIG. 12 shows an operation example in the case where voice communication is performed between the extension terminal 11 (extension A1) and the extension terminal 14 (extension C1) shown in FIG. However, the first operation example is based on the following premise. (1) The dial number is not a dial number of an emergency telephone such as a police station or a fire station, but a general dial number. (2) The media type is “0: voice terminal”.

First, when the user of the extension terminal 11 dials the telephone number of the extension terminal 14 (extension C1) from the extension terminal 11 (extension A1), the dial number (DN) of the extension terminal 14 is obtained.
Is transmitted from the extension terminal 11 to the exchange 13 (1).

When exchange 13 receives the dialed number,
In the exchange 13, the call control unit 24 recognizes that the route is to the Internet 16, and the above-described processes of S01 to S18 (see FIGS. 7 and 8) are executed (2). As a result, a call setup message including the media type “0: voice terminal” and a priority class corresponding to the media type is created, and the call setup message is transmitted from the exchange 13 to the connection device 17 (3).

When the connection device 17 receives the call setup message, the connection device 17 transmits the message to the central control device 3 shown in FIG.
2 edits the packet containing the received call setup message (4).

That is, the central control unit 32 extracts the dial number from the call setting message and determines that the dial number is not a dial number for an emergency call to a police station or a fire department. Subsequently, the central controller 32 extracts the extension attribute data stored in the user information of the call setting message. That is, the central control device 32 extracts the media type “0: voice terminal” corresponding to the extension number of the calling terminal and the priority class corresponding to the media type.

Next, the central control unit 32 indexes the management table 36 shown in FIG. 10 with the priority class included in the extension attribute data, and extracts the service type corresponding to the priority class.

The central control unit 32 also stores the extracted service type in TOS (Type of Service) in the IP header.
Set in the field (see FIG. 11). Thereafter, the central controller 32 edits the packet by adding an IP header storing necessary information to the call setup message.

The central control unit 32 stores the priority class included in the extension attribute data in the storage data table 37 in association with the call number. Thus, when transmitting a voice packet related to this call, the central control device 32 can set the priority class specified for the voice packet.

Thereafter, the central control unit 32 obtains the IP address of the connection device 18 connected to the exchange 15 as the destination exchange based on the called party number set in the received call setup message, and edits the edited call. A packet including a setting message is set and transmitted to the Internet 16 (5).

Thus, the routers 22 and 23 included in the Internet 16 can execute the existing priority control according to the service type set in the TOS field.

Thereafter, a packet including the call setting message transmitted from the connection device 17 is received by the connection device 18 via the Internet 16. Then, the connection device 1
At 8, the service type (priority class) is stored in the storage data table 37a (6).

That is, the central control device 32a of the connection device 18
Extracts the destination IP address included in the packet and confirms that the destination of the packet is itself. Subsequently, the central control device 32a checks the T of the IP header of the packet.
The service type is extracted from the OS field. next,
The central control device 32a stores the extracted service type in the MM
The data is stored in the storage data table 37a in the storage 33a.

Thereafter, the central control unit 32a extracts a call setup message from the packet and transmits the extracted call setup message to the exchange (7). The transmitted call setup message is received by the exchange 15.

In the exchange 15, a call setting acceptance message corresponding to the call setting message is edited. At this time, in the user user information of the call setting acceptance message, a priority class corresponding to the extension terminal 14 (extension C1) as the receiving terminal and according to the media type is set by substantially the same processing as that of the exchange 13. However, the setting process of the priority class can be set to be performed as needed.

The edited call setting acceptance message is transmitted to the connection device 18 (8). Further, the exchange 15 captures the opposite voice communication line, and thereby, the RTB (Ring
BackTone) is connected (9). On the other hand, the receiving terminal (extension C
A call is made to (1) (10).

The connection device 18 receives the call setting acceptance message transmitted from the exchange 15. The connection device 18 edits the packet by adding an IP header to the call setting acceptance message.

At this time, the central control device 3 of the connection device 18
2a performs the following processing when the priority class of the receiving terminal is included in the call setting acceptance message (8A). That is, the central control device 32a extracts the priority class from the call setting acceptance message. Next, the central control device 32a
The service type corresponding to the extracted priority class is read from the management table 36a. Next, the central controller 32a
Reads the service type (service type stored in the above process (6)) corresponding to the call number included in the call setting acceptance message from the stored data table 37a. Next, the central controller 32a compares the service type read from the table 36a with the service type read from the table 37a. If the service type read from the table 36a is higher than the service type read from the table 37a, the central controller 32a stores (updates) the service type read from the table 36a in the table 37a. On the other hand, when the service type read from the table 36a is lower than the service type read from the table 37a, the central control device 32a does not update the table 37a.

After that, the edited packet is transmitted to the connection device 17 through the Internet 16. When the connection device 17 receives the packet, a call setting acceptance message is extracted from the received packet.

At this time, the central control device 3 of the connection device 17
2 performs the following processing when the priority class of the receiving terminal is included in the call setting acceptance message (11A). That is, the central controller 32 extracts the priority class from the call setting acceptance message. Next, the central controller 32 reads the service type corresponding to the extracted priority class from the management table 36. Next, the central controller 32 reads the service type (the service type stored in the above process (4)) corresponding to the call number included in the call setting acceptance message from the stored data table 37. Next, the central controller 32 determines whether the service type read from the table 36 is higher than the service type read from the table 37. If the service type read from the table 36 is higher than the service type read from the table 37, the central controller 32 rewrites the service type stored in the table 37 to the service type read from the table 36. . On the other hand, when the service type read from the table 36 is lower than the service type read from the table 37a, the central control device 32 does not update the table 37.
As described above, when the service type (priority class) corresponding to the receiving terminal is higher than the service type (priority class) corresponding to the calling terminal, the service type corresponding to the receiving terminal becomes the service type corresponding to the call number. Selected.

Thereafter, the connection device 17 transmits a call setting acceptance message to the exchange 13 (12). Exchange 13
Receives the call setting acceptance message.

By the way, according to the above (13), the RBT connected to the opposite voice communication line is connected to the first C
TDM in the ODEC unit 34a or the second CODEC 35a
(Time Division Multiplexing) Input via interface. Then, the RTB receives the first CODEC 34a or the second CODEC 34a.
The data is converted into voice packet data by the DEC unit 35a. Thereafter, an IP header is added to the converted voice packet data. As a result, the packet (RBT voice packet) is edited (14).

When the RBT voice packet is edited, the service type corresponding to the call number is read from the stored data table 37a and set in the TOS field of the IP header. The edited RBT voice packet is
It is transmitted to the Internet 16 (15).

The service type set in the TOS field is recognized by the exchanges (for example, routers 22 and 23) on the transmission line of the RBT voice packet in the Internet 16, and the routers 22 and 23 and the like perform priority control (for example,
It is used when executing (congestion control).

The connection device 17 receives the RBT voice packet transmitted from the connection device 18 via the Internet 16. Then, in the connection device 17, the received RBT
The voice packet data in the voice packet is the first CODEC
The data is decoded into an RBT by the unit 34 or the second CODEC unit 35.

Thereafter, the decrypted RBT is transmitted to the connection device 1
7 through the TDM interface to the exchange 13 and the
It is passed to the line circuit of 1 (extension terminal 11) (16).

When a call is passed from the exchange 15 to the extension C1 (extension terminal 14) (10), the ringer of the extension C1 rings (17). In response, the user at extension C1 performs a response operation (for example, picking up the telephone handset).
(18), a response signal is input to the exchange 15 from the extension C1 (19). Then, the exchange 15 detects the response of the extension C1, edits the response message, and transmits it to the connection device 18 (20).

In the connection device 18, when the response message is received, the central control unit 32a adds an IP header to the response message and transmits the response message to the Internet 16 as a packet (21).

This packet is received by the connection device 17 through the Internet 16. Then, the connection device 17
Extracts the response message from the received packet,
The extracted response message is passed to the exchange 13 (22).

Then, the extension A1 accommodated in the exchange 13
(Extension terminal 11) and the extension C1 accommodated in the exchange 15.
(Extension terminal 14) is in a talking state (a call is established between the terminals). Thereafter, when voice is input from the extension device 11 (extension A1) accommodated in the exchange 13, voice data relating to the voice is transmitted from the exchange 13 and received by the connection device 17.

In the connection device 17, the first CODEC unit 34
Alternatively, the second CODEC unit 35 converts the received audio data into audio packet data. Then, the central control unit 32
Edits a packet (voice packet) containing voice packet data by adding an IP header to the voice packet data (24).

At this time, the central control unit 32 acquires the service type acquired at the time of call setting from the stored data table 37 and sets the acquired service type in the TOS field of the IP header. Thereafter, the edited voice packet is transmitted to the connection device 17.
Is transmitted to the Internet 16 (25).

The service type set in the TOS field is used when priority control is performed by the routers 22 and 23 in the Internet 16. That is, in the Internet 16, priority control is performed according to the priority class specified by the exchange 13 or 15.

Thereafter, the voice packet is received by the connection device 18. In the connection device 18, voice packet data is extracted from the voice packet, and the first CODEC unit 34a or the second CODEC unit 35a decodes the voice packet data into voice data. After that, the decoded audio data is
From the TDM interface of the connection device 18 to the exchange 15
Is passed to the line circuit of the extension C1 via the network circuit (26). Thereby, the voice corresponding to the voice data is output from the extension C1, and the user of the extension C1 can hear the voice input from the extension A1.

On the other hand, when voice is input to the extension terminal 14 (extension C1), voice data corresponding to the voice is transmitted from the exchange 15 and input to the connection device 18 (27). Then, in the connection device 18, the input audio data is converted into audio packet data by the first CODEC unit 34a or the second CODEC unit 35a.

Thereafter, the central control unit 32a of the connection device 18
Edits the voice packet by adding an IP header to the voice packet data (28). At this time, the central control unit 32a extracts the service type corresponding to the call number corresponding to this call (the service type obtained at the time of setting up the call for this call) from the stored data table 37a, and extracts the TOS of the IP header. Set in the field. Thereafter, the edited voice packet is transmitted to the Internet 16 (29).

Thereafter, the voice packet is received by the connection device 17 through the Internet 16. Then, the central control unit 32 of the connection device 17 extracts voice packet data from the received voice packet. The extracted voice packet data is stored in the first CODEC unit 34 or the second CODE
The data is decoded into audio data by the C unit 35.

The decoded voice data is passed from the TDM interface of the connection device 17 to the line circuit of the extension terminal 11 (extension A1) via the network circuit of the exchange 13. Thereby, the voice based on the voice data is output from the extension terminal 11 (extension A1), and the user of the extension A1 can hear the voice input from the extension C1.

According to the first operation example, as shown in the operation explanatory diagram of FIG. 14, a priority class is set for each extension number of an extension terminal (extension) accommodated in each of the exchanges 13 and 15, and the priority class is set. The exchanges 13 and 15 hold information on the related information.

Thereafter, the Internet 16 is connected between the extension terminals.
When a call is set up, the priority class corresponding to the extension number of the calling terminal is transmitted from the exchange to each of the connecting devices 17 and 18.
, Each of the connection devices 17 and 18 acquires the service type corresponding to the priority class, and holds the service type in association with the call specific information. However, if the priority class corresponding to the extension number of the receiving terminal is higher than the priority class corresponding to the extension number of the calling terminal, each connection device 1
Reference numerals 7 and 18 hold the service type corresponding to the priority class of the receiving terminal in association with the call specific information.

Then, the connection device is connected to the Internet 16
When a voice packet is transmitted to the Internet 1, the service type corresponding to the call is included in the voice packet, and
Send to 6.

Thereafter, in the Internet 16, when an exchange or a transmission device existing on the voice packet transmission path such as the routers 22 and 23 receives the voice packet, the service type in the voice packet is referred to, and the priority according to the service type is referred to. Control is executed. For example, congestion control of the Internet 16 is executed.

That is, when congestion occurs on the Internet 16, an exchange or a transmission device within the Internet 16
(For example, the router 22) detects the congestion. Then, the router 22 extracts the service type of the voice packet received by itself, and executes processing for eliminating congestion based on the extracted service type. For example, router 2
2 as congestion control, changing the transmission order of the voice packets, notifying the connected device of the occurrence of congestion,
For example, the voice packet is discarded.

Thus, the voice packet in which the service type corresponding to the high priority class is set is transmitted to the router 2
2 is sent preferentially. Therefore, the delay and loss of the voice packet are suppressed, and the quality of voice communication is maintained.

On the other hand, the voice packets set with the service type corresponding to the low priority class are discarded, and the transmission of the voice packets set with the low priority class to the Internet 16 is suppressed. Is eliminated.

As described above, according to the VoIP system according to the embodiment, the service type corresponding to the priority class corresponding to the extension number of the extension terminal is set in the voice packet. Therefore, the contents of the priority control on the Internet 16 can be set for each extension (extension terminal) accommodated in the exchange. For example, extension importance (priority class)
, The congestion control of the Internet 16 can be executed. Therefore, the reliability of the VoIP system can be improved.

In the VoIP system according to the present embodiment, the exchange 13 notifies the connection device 17 of the priority class corresponding to the media type. Therefore, the central control device 32 of the connection device 17 transmits the priority class corresponding to the media type. Can be set to the voice packet.

Thus, when data requiring higher communication quality than voice data is generally transmitted from the calling terminal to the called terminal, the Internet uses a higher priority class than the priority class set for voice communication. The priority control in 16 is executed.

On the other hand, for example, when data whose transmission delay is less considered than voice data is transmitted from the calling terminal to the called terminal, the Internet 16 uses a lower priority class than the priority class set for voice communication. Is performed. Therefore, priority control according to the attribute of the data to be transmitted can be executed in the Internet 16.

Therefore, priority control according to the attribute of data to be transmitted can be executed in the Internet 16.

The following are used as the rules for media in the VoIP system for the facsimile transmission system, data transmission system, and image (moving image) data transmission system. (1) FAX transmission method (when the media type of the extension terminal is FAX
Real-time fax transmission ・ Fax Relay: FRF.11 Annex D ・ T.38 (2) Data transmission method (when the media type of the extension terminal is a data terminal) Complies with the Internet protocol ・ RFC854 (Telenet: File Transfer Protocol) RFC959 (FTP: File Transfer Protocol) (3) Image data transmission method (when the media type of the extension terminal is an image terminal) The image data format conforms to a prescribed format such as MPEG. For moving image transfer, real-time data transmission is required as with audio. (4) Currently, H225, H
245, H323, H450 and the like are standardized.

The following standardization trends will be made in the future. -"Mapping QSIG to H.225.0" (ECMA proposal)-"Tunnelling QSIG over H.225.0" (ECMA proposal)-"QSIG + as a replacement for H.225.0" (Japan proposal) (Second operation example) , A second operation example of the VoIP system will be described. FIG. 15 is a sequence diagram illustrating a second operation example. In the second operation example, it is assumed that congestion occurs on the Internet 16 during a call between the extension terminal 11 (extension A1) and the extension terminal 14 (extension C1) in the first operation example. When congestion occurs on the Internet 16, the voice quality of a call may deteriorate.

The user of extension A1 or extension C1 (extension A1 in FIG. 15) dials the special priority control number (201). Then, the dial number of the special priority control number is input to the exchange 13 from the extension A1 (202).

When the exchange 13 receives the special priority control number, the exchange 13 executes the processing shown in FIGS. 7 and 8, thereby editing the INFO message including the priority class "highest priority". (203). Thereafter, the edited INFO message is transmitted from the exchange 13 to the connection device 17 (204).

When the connection device 17 receives the INFO message, the central control device 32 of the connection device 17
The service type corresponding to the priority class “highest priority” included in the FO message is extracted from the management table 36.
Subsequently, the central control device 32 updates the corresponding part of the stored data table 37 with the extracted service type (2
05). As a result, the priority class for the call between the extension terminal 11 and the extension terminal 14 increases.

Thereafter, the central control unit 32 sends the extracted service type to the INF where the extracted service type is stored in the TOS field.
The packet including the O message is edited and transmitted to the connection device 18 via the Internet 16 (206).

When the connection device 18 receives the packet, in the connection device 18, the central control device 32a extracts the service type from the packet and updates the corresponding part of the storage data table 37a with this service type (207).

Then, voice packets are input to the extension terminals 11 and 14 so that voice packets are transmitted to the connection devices 17 and 18.
, The service type set in the voice packet rises to the service type corresponding to the priority class “highest priority”.

As a result, even if the Internet 16 is congested, a process for suppressing the deterioration of the voice quality is preferentially performed on the voice packet related to the call.
Therefore, delay and loss of voice packets can be suppressed.

According to the second operation example, when the voice quality deteriorates during a call, if the user dials the special priority control number, the service type (priority class) for the voice packet corresponds to the calling terminal. Rise higher than priority class. As a result, it is possible to suppress deterioration of the voice quality, for example, interruption of the voice or disconnection of the call.

(Third Operation Example) Next, a third operation example of the VoIP system will be described. FIG. 16 is a sequence diagram illustrating a third operation example. The third operation example is an operation example in a case where the dial number dialed at the extension terminal (extension) is a dial number for an emergency call to a police station or a fire department.

In FIG. 16, for example, when an emergency telephone number is dialed at the extension terminal 11 (301), the dialed number is input to the exchange 13 (302), and the exchange 1
At step 3, the operation shown in FIGS. 7 and 8 is performed, and the call setup message is edited (303). Thereafter, the call setting message is transmitted to the connection device 17 (304).

When connection device 17 receives the call setup message, central control device 32 of connection device 17 analyzes the dial number of the terminating terminal included in the call setup message.
Accordingly, when the central control device 32 recognizes that the dialed number is an emergency call number, the service corresponding to a priority class equal to or higher than the priority class included in the call setup message (for example, the priority class “highest priority”) is provided. The type is extracted from the management table 36, and the extracted service type is stored in a corresponding location of the storage data table 37 (305).

Thereafter, the central control unit 32 transmits a packet including a call setup message in which the service type corresponding to the priority class "highest priority" is stored in the TOS field to the Internet 16 (306).

When the connection device 18 receives the packet via the Internet 16, the central controller 32a of the connection device 18 extracts the service type stored in the TOS field of the packet, and stores the service type in the stored data table 37a. (307).

Thereafter, the operations after (7) shown in FIG. 12 are performed. At this time, a service type corresponding to the priority class “highest priority” is set in the RBT voice packet or voice packet transmitted to the Internet 16.

According to the third operation example, when the number dialed at the calling terminal is an emergency call number, the service corresponding to the priority class equal to or higher than the priority class set to the extension number of the calling terminal is used. Class is set to voice packet. Therefore, if the dialed number is an emergency contact number, even if congestion occurs in the Internet 16, deterioration in voice quality related to the call is suppressed, and the call is properly performed between the calling terminal and the called terminal. be able to.

(Fourth Operation Example) Next, a fourth operation example will be described. As a fourth operation example, an operation when each of the connection devices 17 and 18 sets a call will be described. Here, the operation of the connection device 17 will be described as an example.

When a call is set up between the extension terminal 11 and the extension terminal 14, a call setup message is transmitted from the exchange 13 to the connection device 17 as described in the first operation example (FIG. 12). (See (3)).

When the central control device 32 of the connection device 17 receives the call setup message, it executes the process (4) shown in FIG. That is, as shown in the flowchart of FIG. 17, when receiving the call setting message (S401), the central control device 32 extracts a priority class from the call setting message (S402), and determines a service type corresponding to the extracted priority class. It is read from the management table 36 (S403).

Subsequently, the central control unit 32 stores the read service type in the storage data table 37 in association with the call number (S404). Then, the central controller 3
2 determines a CODEC for compressing and encoding audio data according to the priority class extracted in S402 (S4).
05).

For example, if the extracted priority class is “highest priority”, the central control unit 32 selects the first CODEC unit 34 for packetizing the voice at a period of 10 ms, and the extracted priority class is the lowest priority class. In the case of the priority class, the second CO that packetizes the voice at a period of 30 ms
The DEC unit 35 is selected.

Thereafter, when a call is set up and the connection device 17 receives voice data from the exchange 13, the central control unit 32 executes a compression coding process of the voice data with the determined CODEC.

When the audio data is compression-encoded by the first CODEC unit 34, the editing time of the audio packet can be shorter than when the audio data is compression-encoded by the second CODEC unit 35. For this reason, the connection device 17
The number of voice packets per unit time transmitted from
The priority class is in descending order. Therefore, high voice quality is secured in the descending order of the priority class.

As described above, the central control unit 32 makes the first CODEC 34 and the second CODEC 34 in accordance with the extracted priority class.
One of the codecs 35 is selected. by this,
CODEC format (compression encoding format) corresponding to the priority class
Is determined. As a result, it is possible to ensure voice quality according to the priority class.

(Fifth Operation Example) Next, a fifth operation example will be described. The fifth operation example is an operation of each of the connection devices 17 and 18 when congestion occurs in the Internet 16 during a call between the calling terminal and the called terminal. Here, the operation of the connection device 17 will be described as an example.

When congestion occurs on the Internet 16,
For example, the occurrence of congestion is notified from the Internet 16 to each of the connection devices 17 and 18. Thereby, the connection device 17
The central control device 32 performs the operation shown in the flowchart of FIG.

That is, when detecting the congestion of the Internet 16 (S501), the central controller 32 reads the service type corresponding to the currently set call from the stored data table 37 (S502).

Subsequently, the central control unit 32 determines whether the read service type is a service type corresponding to a priority class equal to or lower than a predetermined priority class (S50).
3). At this time, if the service type corresponds to a priority class equal to or lower than the predetermined priority class, the central control device 32 selects the first CODEC unit 34 as a CODEC for compressing and encoding voice data relating to the call. It is determined whether or not there is (S504).

Here, when the first CODEC unit 34 is selected (S504; Y), the central control unit 32
CODEC for compressing and encoding voice data related to the call
Is changed from the first CODEC unit 34 to the second CODEC unit 35 (S505).

Thus, a voice packet corresponding to a call in which a priority class equal to or lower than a predetermined priority class is set is compression-coded by the second CODEC unit 35. Therefore, the number of audio packets edited per unit time decreases,
The number of voice packets transmitted to the Internet 16 is suppressed. Therefore, congestion in the Internet 16 is reduced.

On the other hand, voice data corresponding to a call in which a priority class higher than the predetermined priority class is set is the first COD
The data is compression-coded by the EC unit 34. For this reason, the deterioration of the voice quality is preferentially suppressed, and the communication quality is maintained.

It should be noted that each of the connection devices 17 and 18 uses the ITU-T G114
Specifies the following recommendations for END-to-END Delay.・ 0 to 150 ms: Acceptable ・ 150 to 400 ms: Acceptable after the administrator acknowledges
(Quality comparable to satellite communication)-400 ms-: Unacceptable for general use.
Interworking between Satellite Communication and Cellular In special cases such as videoconferencing using satellite communication and interworking between cellular, the above limits may be exceeded.

In the VoIP system, END-to
The equipment and delay related to -END Delay are as follows. -Network access equipment (router, etc.) Delay is generally about 10 ms-Transmission network ISDN line: 7 ms Public frame relay: 20 to 40 ms (one end) Internet: 50 to 400 ms (Sixth operation example) An operation example will be described. The sixth operation example is different from the fourth and fifth operation examples described above in that, for example, when only the first CODEC units 34 and 34a are used in the compression encoding of the audio data in the respective connection devices 17 and 18. It is an operation example.

In the sixth operation example, when a call is set, the first CODE is used as a CODEC for compressing and encoding voice data.
Only the C section 34 (first CODEC section 34a) is selected.

Thereafter, congestion occurs in the Internet 16 during a call, and when this congestion is detected by each of the connecting devices 17 and 18, each of the connecting devices 17 and 18 performs the operation shown in the flowchart of FIG. Will be Here, the connection device 17 will be described as an example.

When detecting the congestion (S601), the central control unit 32 of the connection device 17 reads out the service type corresponding to the currently set call from the stored data table 37 (S602). Subsequently, the central control device 32 determines whether the read service type is a service type corresponding to a priority class equal to or lower than a predetermined priority class (S60).
3).

At this time, when the service type corresponds to a priority class lower than the predetermined priority class (S6).
03; Y), the central controller 32 increases the number of voice packet data stored in the voice packet (S60).
4).

By the above operation, the transmission interval of the voice packet corresponding to the call in which the priority class lower than the predetermined priority class is set is extended. Therefore, the number of voice packets transmitted per unit time corresponding to the call is reduced, and the number of voice packets transmitted to the Internet 16 is suppressed. Therefore, congestion in the Internet 16 is reduced.

On the other hand, the number of voice packet data stored in a voice packet corresponding to a call in which a priority class exceeding a predetermined priority class is set is not changed. Therefore, the number of transmitted voice packets corresponding to the call is not changed.

[0146] Therefore, a voice packet having a higher priority class is transmitted to the Internet 16 preferentially.
For this reason, for a call having a higher priority class, the deterioration of the voice quality is preferentially suppressed, and the communication quality is maintained.

In the present embodiment, the voice from the extension terminal 11 as the telephone terminal is transmitted to the exchange 13 and the connection device 1.
7 has been described, the present invention relates to a case in which data from a computer terminal is transmitted to an IP network via a circuit switching network (switch 13) and a connection device 17. Is also applicable. That is, the present invention provides
It is preferably applied to a call using VoIP, but it can also be applied to data communication between terminal devices.

[Appendix] The present invention can be specified as follows. (Supplementary Note 1) A first exchange accommodating a plurality of first terminals, a first connection device connected to the first exchange, a second connection device connected to the first connection device through an IP network, At least one second terminal connected to the IP network through a second connection device, wherein the first exchange holds a priority class corresponding to each of the first terminals, and wherein the first connection device includes: Holding a service type corresponding to each priority class, wherein the first exchange sets up a call through an IP network between any one of the first terminals as a calling terminal and the second terminal as a called terminal In addition, the first connection device notifies the first connection device of a priority class corresponding to the first terminal as an originating terminal, and the first connection device reads out a service type corresponding to the notified priority class, and reads out the service type. When the service type is stored, and the first connection device transmits a packet including data from the first terminal as an originating terminal to the IP network after the call is established, the first connection device determines the service type set in the packet. A priority control method for a network system, comprising setting the stored service type in a packet such that the priority control is performed in an IP network. (Supplementary Note 2) The first connection device notifies the second connection device of the read service type, the second connection device stores the notified service type, and the second connection device Is established, when transmitting a packet including data from the second terminal as a receiving terminal to the IP network, the priority control according to the service type set in the packet is performed in the IP network. The method according to claim 1, further comprising setting the stored service type in the packet. (Supplementary Note 3) When the first exchange receives a priority class change instruction during communication between the calling terminal and the called terminal, the first exchange sets a new priority class equal to or higher than the priority class corresponding to the calling terminal to the first exchange. Notifying the connecting device, the first connecting device reads a new service type corresponding to the new priority class notified from the first exchange, stores the read new service type, and stores the stored new service type. 2. The priority control method for a network system according to claim 1, further comprising: (Supplementary Note 4) The first connection device notifies the second connection device of the read new service type, and
The connection device stores the new service type notified from the first connection device, and transmits the stored new service type when transmitting a packet including data from the second terminal as the receiving terminal to the IP network. 4. The method according to claim 3, further comprising setting in a packet. (Supplementary Note 5) When a call is set up between a calling terminal and a called terminal, the first exchange specifies a called terminal, and the first exchange determines whether the specified called terminal is a predetermined terminal. The priority control method for a network system according to claim 1, further comprising notifying the first connection device of a priority class equal to or higher than the priority class corresponding to the calling terminal. (Supplementary Note 6) The first connection device determines a compression encoding method of voice data received from the first switchboard according to the notified priority class, and the first connection device determines a voice input to a calling terminal. When the voice data corresponding to the above is received from the first exchange, the received voice data is compression-encoded using the determined compression-encoding method, and a packet including the compression-encoded voice data is edited. 2. The priority control method for a network system according to claim 1, further comprising: (Supplementary Note 7) The first connection device detects a service type or a priority class related to the communication when the congestion related to the communication between the calling terminal and the called terminal occurs in the IP network, and detects the detected service type or the priority class. 7. The priority control method for a network system according to supplementary note 6, further comprising changing a compression encoding method based on the method. (Supplementary Note 8) When the first connection device receives voice data corresponding to voice input to the calling terminal from the first exchange after the call is established, the first connection device compresses and encodes the received voice data, and compresses the received voice data. Editing a packet including encoded voice data, the first connection device sets a service type or a priority class related to communication when congestion related to communication between a calling terminal and a called terminal occurs in an IP network. The network system according to claim 1, further comprising: detecting, wherein the first connection device changes the number of compression-encoded audio data included in one packet based on the detected service type or priority class. Priority control method. (Supplementary Note 9) The second terminal is connected to the second connection device via a second switch, and the second switch is connected to a second switch.
Holding a priority class corresponding to the terminal, the second connection device holding a service type corresponding to the priority class held in the second exchange, and the second exchange is configured to use any one of the first When a call is set up between a terminal and a second terminal as a receiving terminal, the held priority class is notified to the second connection device, and the second connection device corresponds to the notified priority class. Reading the service type, the second connection device compares the service type notified from the first connection device with the read service type,
3. The priority control method for a network system according to claim 2, further comprising, if the read service type is higher than the notified service type, storing the read service type instead of the notified service type. (Supplementary Note 10) The second connection device notifies the priority class notified from the second exchange to the first connection device, and the first connection device changes the priority class notified from the second connection device to the priority class. A corresponding service type is obtained, and the obtained service type is compared with the stored service type corresponding to the priority class notified from the first exchange, and the obtained service type is higher than the stored service type. 10. The method according to claim 9, further comprising storing the obtained service type in place of the stored service type. (Supplementary Note 11) The first exchange holds a priority class according to the attribute of each first terminal, and a call is established between any one of the first terminals as the calling terminal and the second terminal as a called terminal. The priority control method for a network system according to claim 1, further comprising, when set, detecting an attribute of the first terminal as the calling terminal and notifying the first connection device of a priority class corresponding to the detected attribute. . (Supplementary Note 12) A network system that includes an exchange accommodating a plurality of extension terminals and an IP network connection device connected to the exchange, and provides communication through an IP network, wherein the exchange includes the terminal. And a priority class storage unit for storing a priority class corresponding to the terminal, and a priority class corresponding to the terminal as the originating terminal when the call with any terminal as the originating terminal is set through the IP network, from the priority class storage unit. An acquisition unit to acquire,
A priority class notification unit that notifies the connection device of the priority class obtained by the obtaining unit, wherein the connection device stores a service type corresponding to each priority class held in the exchange. A reading unit that reads a service type corresponding to a priority class notified from the exchange from the service type storage unit, and a storage unit that stores the service type read by the reading unit as a service type related to a set call. Transmitting a packet including data from the calling terminal to the IP network after the call is established,
A setting unit configured to set the stored service type in the packet so that priority control based on the service type set in the packet is performed in the IP network. (Supplementary Note 13) An exchange that accommodates a plurality of extension terminals and is connected to an IP network connection device that transmits a packet with a service class set to the IP network, and retains a priority class corresponding to each of the terminals. And a priority class corresponding to a terminal as a calling terminal when a call in which any of the plurality of terminals is a calling terminal is set up through the IP network, from the priority class storing unit. An exchange, comprising: an acquisition unit; and a priority class notification unit that notifies the connection device of the priority class acquired by the acquisition unit. (Supplementary Note 14) A service type of an IP network connecting device for connecting an exchange accommodating a plurality of terminals and an IP network, wherein the service types hold service types respectively corresponding to the priority classes of the respective terminals held in the exchange. A storage unit, a receiving unit that receives a priority class corresponding to a terminal as an originating terminal from the exchange when a call in which one of the plurality of terminals is an originating terminal is set through an IP network; A reading unit that reads a service type corresponding to the priority class received from the service type storage unit, a storage unit that stores the service type read by the reading unit as a service type for a set call, Is established, the packet containing the data from the originating terminal is transmitted to the IP network. , As priority control based on the service type set in the packet is executed in the IP network, IP network connection device including a setting unit for setting a service type which is the storage in the packet.

[0149]

According to the present invention, priority control can be performed in an IP network according to the priority set for each terminal accommodated in the exchange.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a VoIP network system according to an embodiment.

FIG. 2 is a functional block diagram of a central control unit shown in FIG. 1;

FIG. 3 is an explanatory diagram of a main storage device shown in FIG. 1;

FIG. 4 is an explanatory diagram of a dial number-trunk number conversion table shown in FIG. 3;

FIG. 5 is an explanatory diagram of an extension attribute data table corresponding to extension numbers shown in FIG. 3;

FIG. 6 is an explanatory diagram of a trunk number-corresponding trunk attribute data table shown in FIG. 3;

FIG. 7 is a flowchart showing processing by the exchange shown in FIG. 1;

FIG. 8 is a flowchart showing processing by the exchange shown in FIG. 1;

FIG. 9 is a configuration diagram of the connection device shown in FIG. 1;

FIG. 10 is an explanatory diagram of a priority class correspondence management table shown in FIG. 9;

11 is an explanatory diagram of a call number corresponding priority class storage data table shown in FIG. 9;

FIG. 12 is a sequence diagram showing a first operation example.

FIG. 13 is an explanatory diagram of a packet format.

FIG. 14 is a diagram illustrating the operation of the first operation example.

FIG. 15 is a sequence diagram showing a second operation example.

FIG. 16 is a sequence diagram showing a third operation example.

FIG. 17 is a flowchart illustrating a fourth operation example;

FIG. 18 is a flowchart illustrating a fifth operation example;

FIG. 19 is a flowchart illustrating a sixth operation example;

FIG. 20 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

11, 12, 14 extension terminal 13, 15 exchange 16 Internet 17, 18 Internet connection device 20, 20a Central controller (acquisition unit, priority class notification unit) 21, 21a main storage device (priority class storage unit) 22, 23 router 24 call control processing unit (acquisition unit) 25 ISDN program control unit 26 ISDN message editing processing unit 27 ISDN message transmission processing unit (priority class notification unit) 28 memory information 29 dial number-trunk number conversion table 30 extension attribute corresponding extension data Table (priority class storage unit) 31 Trunk number corresponding trunk attribute data table 32, 32a Central control unit (read unit, storage unit, setting unit, reception unit, editing unit, transmission unit) 33, 33a Main storage unit (service type storage) Unit) 34,34a First CODEC unit (compression encoding unit) 35,35a Second CODEC unit (compression unit) Compression encoding unit) 36, 36a Priority class correspondence management table (service type storage unit) 37, 37a Call number correspondence priority class storage data table (storage unit)

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) JJ05 JJ11 JJ12 JJ13

Claims (10)

[Claims] A first exchange accommodating a plurality of first terminals;
A first connection device connected to the first exchange;
A second connection device connected to the connection device through an IP network, and at least one second terminal connected to the IP network through the second connection device, wherein the first exchange is connected to each of the first terminals. Holding a corresponding priority class, the first connection device holding a service type corresponding to each of the priority classes, and the first exchange, the first exchange as one of a first terminal as a calling terminal and a second terminal as a called terminal. When a call through an IP network is set up between two terminals, the first as a calling terminal
Notifying the first connection device of a priority class corresponding to the terminal, the first connection device reads a service type corresponding to the notified priority class, stores the read service type, When a packet including data from a first terminal as a calling terminal is transmitted to an IP network after the call is established, priority control according to a service type set in the packet is performed in the IP network. And setting the stored service type in a packet. 2. The first connection device notifies the read service type to a second connection device, the second connection device stores the notified service type, and the second connection device When a packet including data from the second terminal as a terminating terminal is transmitted to the IP network after the call is established, priority control according to a service type set in the packet is performed in the IP network. The method according to claim 1, further comprising: setting the stored service type in a packet. 3. The first exchange, when receiving an instruction to change a priority class during communication between a calling terminal and a called terminal, sets a new priority class higher than the priority class corresponding to the calling terminal. The first connection device reads a new service type corresponding to the new priority class notified from the first exchange, stores the read new service type, and stores the stored new service. The method according to claim 1, further comprising setting the type to packet. 4. The first connection device notifies the read new service type to the second connection device, and the second connection device notifies the new service type notified from the first connection device. Save the second as the receiving terminal
4. The method according to claim 3, further comprising, when transmitting a packet including data from the terminal to the IP network, setting a new service type stored in the packet. 5. The first exchange specifies a destination terminal when a call is set up between a calling terminal and a destination terminal, and the first exchange is a specified terminal for the specified destination terminal. 2. The method according to claim 1, further comprising notifying the first connection device of a priority class equal to or higher than the priority class corresponding to the calling terminal. 6. The first connection device determines a compression encoding method for voice data received from the first exchange according to the notified priority class, and the first connection device receives a signal from a calling terminal. When voice data corresponding to voice is received from the first exchange, the received voice data is compression-encoded using the determined compression coding method, and a packet including the compression-coded voice data is edited. 2. The priority control method for a network system according to claim 1, further comprising: 7. The second terminal is connected to the second connection device via a second exchange, the second exchange holds a priority class corresponding to the second terminal, and the second connection The device holds a service type corresponding to the priority class held in the second exchange, wherein the second exchange performs a call between any one of the first terminals as the calling terminal and the second terminal as the called terminal. Is set, the held priority class is notified to the second connection device, the second connection device reads a service type corresponding to the notified priority class, and the second connection device (1) The service type notified from the connection device is compared with the read service type, and if the read service type is higher than the notified service type, the read service type is notified of the service. Further priority control method of a network system according to claim 2 include storing in place type. 8. The first exchange holds a priority class according to the attribute of each first terminal, and performs a call between any one of the first terminals as the originating terminal and a second terminal as the receiving terminal. 2. The network system according to claim 1, further comprising: detecting an attribute of the first terminal as a calling terminal, and notifying the first connection device of a priority class corresponding to the detected attribute, when is set. Priority control method. 9. An exchange which accommodates a plurality of extension terminals and is connected to a connection device of an IP network for transmitting a packet in which a service class is set to an IP network, wherein a priority class corresponding to each terminal is set. A priority class storage unit for holding, and a call in which any one of the plurality of terminals is a calling terminal is the IP
An obtaining unit that obtains a priority class corresponding to a terminal as a calling terminal from the priority class storage unit when the setting is performed via a network; and a priority class notification that notifies the connection device of the priority class obtained by the obtaining unit. The exchange including the department. 10. An IP network connection device for connecting an exchange accommodating a plurality of terminals to an IP network, wherein the service retains service types respectively corresponding to the priority classes of the respective terminals held in the exchange. A type storage unit; a receiving unit that receives a priority class corresponding to a terminal as a calling terminal from the exchange when a call in which any of the plurality of terminals is a calling terminal is set through an IP network; A reading unit that reads a service type corresponding to the priority class received by the unit from the service type storage unit; a storage unit that stores the service type read by the reading unit as a service type for a set call; After the call is established, send a packet containing data from the calling terminal to the IP network That if, as priority control based on the service type set in the packet is executed in the IP network, IP network connection device including a setting unit for setting a service type which is the storage in the packet.