JP2002374309A - Internet telephone system using isdn telephone terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize low cost for toll calls, even in general household having no LAN environment or PC. SOLUTION: Voice data, converted to an IP packet within an ISDN terminal, is housed in the B channel of ISDN, and the B channel data is reconverted to the IP packet by a VoIP gateway installed on the side of an exchange station, to realize internet telephone function via IP.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for converting digitally converted voice data into an IP packet,
The present invention relates to an ISDN telephone terminal that provides Internet phone services by transmitting P packets, and a switching facility.

[0002]

2. Description of the Related Art In recent years, for the purpose of reducing communication costs, a VoI using an IP network without using a public communication network or a dedicated line.
Companies and individuals using Internet phones by P are increasing. Companies having a LAN environment have realized an Internet phone by connecting a telephone terminal having an Ethernet (registered trademark) interface to an in-house LAN, and connecting a VoIP gateway on the same LAN to an IP network. Also, although it does not have a LAN environment,
If you own a PC, install the Internet phone software on your PC, and install a microphone, speaker,
Or connect headphones etc., dial up or
ISP (InternetS
An Internet phone is realized by connecting to an Internet service provider.

[0003]

However, the Internet phone requires a telephone terminal to be connected to a LAN network, and cannot be used in ordinary households without a LAN environment. The Internet phone using the PC application software can be used only by the person who owns the PC, and it is necessary to activate the PC when making a long distance call.

An object of the present invention is to solve the above-mentioned problems and to provide an inexpensive toll-free telephone call using an IP network in an ordinary household without using any device other than a telephone terminal.

[0005]

According to the present invention, a voice is converted into a digital signal, and the voice is converted into a digital signal. H.323, a code compression method using a method based on H.323, and a function of converting the compressed data into IP packets.
A function of accommodating an IP packet in which a PPP header is added to the B channel of the ISDN line so that the P packet can be transmitted by PPP on the ISDN line;
IP packet from B channel data of
U.T. Recommendation H. H.323 is added to the ISDN telephone terminal with the function of companding the code and converting it into an analog audio signal. If the caller chooses to use the Internet phone function with a changeover switch or the like on the ISDN telephone terminal, the voice is converted to digital, and the ITU-T Rec. After code compression and IP packetization by a method based on H.323, an IP packet with the PPP header added to the B channel of ISDN is accommodated. At the same time I
A flag for identifying that the data of the B channel is an IP packet is inserted into the D channel transmitted from the SDN telephone terminal. On the other hand, if the caller selects the use of the voice communication function by the public line network by a changeover switch or the like on the ISDN telephone terminal, the digitally converted voice is converted to the ITU-T Recommendation G.3. Code compression based on 711, B
Accommodate in channel. Next, on the switching center side, a D-channel flag transmitted from the ISDN subscriber is read by a line distributing unit installed in the preceding stage of the voice circuit exchange, and if the received data is circuit-switching data, The B channel data and the D channel data of the user are transmitted to the voice circuit exchange. If the received data is an IP packet, the subscriber's B channel data and D channel data
Send the data to the VoIP gateway. The VoIP gateway transmits the telephone number of the calling party and the telephone number of the called party to an authentication server installed in the same exchange. The authentication server authenticates the caller and the called party. If both are subscribers of the Internet phone, the B-channel data is restored to IP packets by the VoIP gateway, and the caller and the called party are restored. Assign an IP address, insert this IP address into the IP packet,
It is transmitted to the IP network by IP. Conversely, UDP from IP network
The VoIP gateway that has received the IP packet by the / IP accommodates the received IP packet in the B channel of the ISDN and transmits it to the line distribution unit. The line distribution unit is a BRI (Basic Rate Int) of ISDN.
The data is transmitted to the called ISDN terminal in the form of "interface". The ISDN terminal that has received the data restores the B channel data into an IP packet, and returns to ITU-T Recommendation H.264. 323, and converts it into an analog audio signal. With this system, an ISDN subscriber can make an inexpensive toll call simply by connecting the ISDN telephone terminal to an ISDN line. Also, by performing A / D conversion, code compression and IP packetization of voice on the terminal side, code compression of voice data and IP
Packetization becomes unnecessary, and the processing of the VoIP gateway installed in the exchange can be reduced.

[0006]

FIG. 1 is a block diagram of the present invention.
The ISDN terminal 1 is connected to the ISDN line 2 and transmits B channel data and D channel data to the exchange 3 in the ISDN BRI format. On the switching center 3 side, the line distribution unit 4 transmits the data to the VoIP gateway 5 from the received D channel identification flag when the B channel data is an IP packet. If the B channel data is voice data, the data is transmitted to the circuit switch 6.
The VoIP gateway 5 that has received the data transmits the telephone number of the calling party and the telephone number of the called party to the authentication server 7.
The authentication server 7 searches whether the subscriber of the received telephone number is registered in the Internet phone service.
If both the calling party and the called party are registered in the Internet phone service, the B channel data received by the VoIP gateway 5 is restored to an IP packet,
The IP addresses of the caller and the callee are assigned and inserted into the IP packet. The IP packet generated in this way is UD
P / IP via the IP network 8 to the called exchange 10
To the VoIP gateway 11. VoIP gateway 1 of called exchange 10 receiving the IP packet
1 accommodates the received IP packet in the ISDN B channel. The ISDN B-channel data containing the IP packet is transmitted from the distribution unit 14 to the ISDN telephone terminal 16 of the called party. Upon receiving the B-channel data, the ISDN telephone terminal 16 restores the B-channel data into an IP packet, and returns to the ITU-T Recommendation H.264. 323 based on code compression and conversion to analog voice. If the B channel data is audio data, DSS1 (Digit
al Subscriber Signaling
System No. 1) Data transmission / reception is performed between the ISDN telephone terminal 1 of the calling party and the ISDN telephone terminal 16 of the called party via the public communication network 9 based on the protocol.

FIG. 2 shows a configuration diagram of a voice data conversion unit in an ISDN terminal according to the present invention. The voice input from the receiver 18 is digitally converted by the A / D converter 19. The digitized voice data is transmitted to the Internet phone code compression section 20 by the ITU-T Recommendation H. H.323 code compression is performed. Next, RTP (Realtime Transfer Pro) is added to the data compressed by the IP packet generator 22.
tocol) header, a UDP header, and an IP header, and are converted into IP packets, a PPP header is added, and the data is divided into 8-bit data.
Send to Also, an internet phone identification flag and 8
The sequence number of the IP packet divided for each bit is D
It is transmitted to the channel processing LSI 25. On the other hand, when a telephone call is made via a public communication network, digitized voice data is encoded by the voice communication code compression unit 21 according to ITU-T Recommendation G.3.
The code is compressed based on the μ-LAW of 711 and transmitted to the B-channel processing LSI 24. Conversely, on the receiving side, the voice call / Internet phone determination unit 23 reads the received D-channel Internet phone identification flag, and if the received data is Internet phone IP data,
The B channel data is transmitted to the IP packet restoration unit 28. The IP packet restoring unit 28 restores the received B channel data from the sequence number of the simultaneously received D channel data into an IP packet, and converts the audio data contained in the data portion of the IP packet into a code companding unit 26 for the Internet phone. Send to The code compander 26 for the Internet phone uses the ITU-T Recommendation H.264. In accordance with H.323, the code is expanded and converted into an analog audio signal by the A / D converter, and the analog audio signal is transmitted to the receiver. If the received data is voice data of a voice call via a public communication network, the voice communication code compander 27 converts the B channel data into ITU-T Recommendation G. Code companding based on μ-LAW of 711, A / D
The conversion unit 19 converts the signal into an analog voice signal and transmits the analog voice signal to the receiver.

[0008]

By using the present invention, an ISDN subscriber can connect an ISDN telephone terminal to an ISDN line, and can make a toll call at a lower rate than a call using a conventional public communication network. It becomes possible. In addition, a voice call between the Internet phone and the public communication network can be selected by a changeover switch, so that the user selects the Internet phone when the call charge is to be reduced and the voice call via the public communication network when the call quality is to be prioritized. I can do things.

The ISDN telephone terminal according to the present invention performs code compression and IP packetization of digital voice data on a one-chip DSP (Digital Signal Process).
The above service can be provided by a terminal having the same size as a conventional ISDN telephone terminal.

In the present invention, the case where an ISDN telephone terminal is used has been described as an example.
An ADSL (Asymmetric Digital) that connects a packet generator and a modem and uses an analog subscriber line
al SubscriberLine).

[Brief description of the drawings]

FIG. 1 is a configuration diagram of the present invention.

FIG. 2 is a diagram showing a voice data conversion unit of the ISDN telephone terminal of the present invention.

[Explanation of symbols]

1 ISDN telephone terminal Telephone terminal 2 ISDN line 3
... switching station, 4 ... line sorting unit, 5 ... VoIP gateway, 6 ... authentication server, 7 ... line switch, 8 ... IP network,
9 public telephone network, 10 exchange office, 11 authentication server, 1
2 ... VoIP gateway, 13 ... Circuit exchange, 14 ...
Line distribution unit, 15: ISDN line, 16: ISDN
Telephone terminal, 17: changeover switch, 18: handset, 1
9 A / D conversion unit, 20 code compression / compression unit for Internet phone, 21 code compression / compression unit for voice communication, 22
... IP packet generation unit, 23 ... Internet phone / voice call determination unit, 24 ... LSI for B channel processing, 25 ...
LSI for D-channel processing, 26 code compression unit for Internet phone, 27 code compression unit for voice communication, 28 IP
Packet recovery unit.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor, Yu Mitsui 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture F-term in the Communications Division, Hitachi, Ltd. 5K030 GA08 GA20 HA01 HA08 HB01 HC01 HC05 HD03 HD05 JL08 JT01 LB13 5K051 BB01 CC04 DD01 5K101 LL03 MM04 RR05 SS08

Claims (4)

[Claims] 1. A telephone terminal which is connected to a subscriber line of a public communication network and has a function of converting voice into an IP (Internet Protocol) packet.
The data received from the telephone terminal via the subscriber line is represented by V if the received data contains an IP packet.
oIP (Voice over Internet P
(Rotocol) When voice data is accommodated in the received data in the gateway, the data is distributed to a circuit switch, and the data received from the circuit distribution unit is restored to an IP packet and transmitted via an IP network. By sending to the called party's telephone terminal
The IP gateway and the authentication of the caller and the callee based on the telephone numbers of the caller and the callee contained in the data received from the line sorting unit, and transmitting the authentication result to the VoIP gateway. A system for accommodating an Internet phone subscriber, comprising: an authentication server having a feature; and a circuit switch for transmitting data received from the line distribution section to a telephone terminal of a called party via a public communication network. 2. The internet telephone subscriber accommodation system according to claim 1, wherein said internet telephone subscriber accommodation system is connected to an ISDN subscriber line, converts voice to digital, and uses ITU-T Recommendation H.264. 323 is converted into an IP packet by code compression using a method based on H.323, and the IP packet is accommodated in the B channel of the ISDN and transmitted to the VoIP gateway installed in the telephone exchange.
Point-to-Point PPP over SDN
protocol, and restores the B-channel data received from the VoIP gateway by the PPP on the ISDN into an IP packet, and converts the voice data stored in the data part of the IP packet into ITU-T Recommendation H.264. H.323 has a function of an Internet phone for making a call by performing code compression / compression and analog conversion by a method based on H.323, and a function of a voice call for making a call via a public telephone network. An ISDN telephone terminal characterized in that the user can select one of the following. 3. The Internet telephone subscriber accommodating system according to claim 1, wherein the identification flag inserted in the D channel data transmitted from the ISDN telephone terminal according to claim 2 allows the B simultaneously transmitted from the ISDN telephone terminal according to claim 2.
B channel where the channel data contains IP data
3. An ISDN according to claim 2, wherein it is determined whether the received data is data or B channel data containing voice data, and if the B channel data is B channel data containing IP data.
When the line accommodating the B-channel data and the D-channel data transmitted from the telephone terminal is sent to the VoIP gateway device, and the B-channel data is voice data,
B channel transmitted from the ISDN telephone terminal according to claim 2.
A line distribution unit for distributing a line containing data and D-channel data to a line switch. 4. The Internet telephone subscriber accommodation system according to claim 1, wherein the B channel data received from the ISDN telephone terminal according to claim 2 is restored to an IP packet,
The caller and the called party are authenticated by transmitting the calling party's telephone number and the called party's telephone number in the D-channel data to an authentication server installed in the same switching center. If the called party is a subscriber of the Internet phone according to the present invention, the IP packets of the calling party and the called party are added to the IP packet, and the IP packet provided with the IP address is transmitted via UDP over an IP network. (User Da
tag / protocol / IP to the called exchange, and the caller's exchange sends a UDP /
A VoIP gateway device, wherein the IP packet received by IP is accommodated in an ISDN B channel and transmitted to a called party by PPP over an ISDN line.