(19) United States
`(12) Patent Application Publication (10) Pub. N0.: US 2002/0027977 A1
`(43) Pub. Date:
`Mar. 7, 2002
`Noguchi
`
`US 20020027977A1
`
`(54) DATA RECORDING SYSTEM FOR IP
`TELEPHONE COMMUNICATION
`
`(57)
`
`ABSTRACT
`
`(75)
`
`IHVCUIOT3
`
`Tada1101'i N0g“Chi> T0kY0 (JP)
`
`Correspondence Address:
`YOUNG & THOMPSON
`745 SOUTH 23RD STREET 2ND FLOOR
`ARLINGTON! VA 22202
`_
`.
`(73) Asslgneez NEC Corporatlon
`.
`(21) Appl' No"
`<2»
`(30)
`
`09/944487
`4,
`Foreign Application Priority Data
`
`Sep. 4, 2000
`
`(JP) .................................... .. 2000-266920
`
`Publication Classification
`
`I
`51
`Cl 7
`.
`nt.
`(52) U.S. Cl.
`
`H04M 1/64
`.................................................... ..
`.......................................................... .. 379/67.1
`
`A data recording system for the IP telephone is provided,
`which complements perfectly the lost voice/speech (or,
`audio) data due to loss of the IP packets during transmission.
`This system comprises: (a) an IP-based network; (b) a first
`telephone terminal connected to the network and capable of
`transmission and reception of audio data in the form of IP
`packets;
`(C)
`a
`second telephone terminal connectable
`directly to the network or indirectly thereto by way of an
`exchange and capable of voice or speech communication;
`and (d) a recording device connected to the network and
`capable of recording audio data transmitted between the first
`:i:;::::C;::::“:;e;:;%;3:212:*:::§;:::;:;::::a;§::
`data are transmitted between the first telephone terminal and
`the second telephone terminal by way of the network in
`approximately real time. Recording IP packets correspond-
`ing to the audio data for the communication are transmitted
`to the recording device by way of the network in a way that
`does not cause any IP packet loss during transmission and
`h
`'
`f
`d '
`l
`'
`h
`b
`d'
`h
`t at is not per orme
`in rea time,
`t ere y recor mg t e
`audio data by the recording device.
`
`DATA RECORDING SYSTEM
`—
`
`IP SUBSCRIBER CIRCUIT
`211
`220
`
`
`IP-BASED NETWORK
`500
`MEMORY
`
`250
`
`
`100A
`IP TELEPHONE
`TERMINAL
`
`TELEPHONE
`
`210 TSW
`
`2
`
`I00
`
`TERMINAL
`
`
`410 W
`
`300
`ADMINISTRATIVE SERVER
`
`400
`PERSONAL COMPUTER
`FOR RECORD I MG
`
`

`
`mMP
`
`Mar. 7, 2002 Sheet 1 of 10
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`US 2002/0027977 A1
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`Patent Application Publication Mar. 7, 2002 Sheet 2 of 10
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`US 2002/0027977 A1
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`Mar. 7, 2002 Sheet 3 of 10
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`Patent Application Publication Mar. 7, 2002 Sheet 4 of 10
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`US 2002/0027977 A1
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`Patent Application Publication Mar. 7, 2002 Sheet 5 of 10
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`US 2002/0027977 A1
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`Patent Application Publication Mar. 7, 2002 Sheet 6 of 10
`
`US 2002/0027977 A1
`
`IP TELEPHONE
`TERMINAL 100
`
`
`RECORDING
`COMPUTER 400
`
`
`IP SUBSCRIBER
`CIRCUIT 220
`
`
`AIIOFF-HOOK+CALL SIGNAL
`
`RECORDING
`MODE
`
`A5 RECORDING START ORDER
`
`
`
`
`
`
`
`
`
`AGZRECORDING START ORDER
`
`
`
`RECORDING
`MODE
`
`AIIIRECORDING PACKETS
`
`
`
`’"“‘I
`
`ABISPEECH PACKETS
`
`AQIRECORDING PACKETS
`
`A10 SPEECH PACKETS
`
`
`
`
`
`
`A2=sPEEcH PACKETS _
`AMPEECH PACKETS _
`
`
`
`
`
` NON—RECORDING
`
`MODE
`
`
`
`
`A13IRECORDING STOP ORDER
`
`A14 RECORDING STOP ORDER
`
`AIGION-HOOK
`+DISCONECT SIGNAL
`
`
`
`
`
`NON-RECORDING
`
`MODE
`
`
`
`
`

`
`o
`.
`.
`.
`Patent Appllcatlon Publlcatlon Mar. 7, 2002 Sheet 7 of 10
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`U
`
`S 2002 0027977 A1
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`Patent Appllcatlon Publlcatlon Mar. 7,2002
`
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`9°
`0
`
`US 2002/0027977A1
`
`FlG.8
`
`E
`
`USER'S OPERATION FOR REPRODUCTION
`
`01
`
`READ RECORDED IR PACKETS
`
`RETRIEVE REAL TIME VALUES
`
`REPRODUCE VOICE DATA
`WITH FIRST REAL-TIME VALUE I
`
`START CLOCK COUNTER
`
`02
`
`03
`
`04
`
`05
`
`
`
`OUNTER VALUE
`=REAL—TIIIE VALUE '2
`
`REPRODECE NEXT [P PACKETS
`
`ALL PACKETS COMPLETED ?
`
`
`
`Y
`
`C8
`
`

`
`Patent Application Publication Mar. 7, 2002 Sheet 9 of 10
`
`US 2002/0027977 A1
`
`VOICE DATA FROM
`LOCAL TELEPHONE
`TERMINAL
`
`REAL TIME : XXA
`
`
`
`RESET
`
`
`
`VOICE DATA FROM
`REMOTE TELEPHONE
`TERMINAL
`
`T1
`
`RI
`
`~e—-——— REAL TlME:YYA
`
`FlG.9
`
`CLOCK COUNTER
`
`
`
`
`
`

`
`Patent Application Publication Mar. 7, 2002 Sheet 10 of 10
`
`US 2002/0027977 A1
`
`F|G.10
`
`600
`/PERSONAL COMPUTER
`
`620
`
`RECORD E . G
`DEVICE
`
`“EL
`
`(TOP)
`
`(UDP, RTP)
`
`630
`STORAGE
`DEV 5 CE
`
`610
`I P TELEPHONE
`TERMINAL
`
`

`
`US 2002/0027977 A1
`
`Mar. 7, 2002
`
`DATA RECORDING SYSTEM FOR IP TELEPHONE
`COMMUNICATION
`
`BACKGROUND OF THE INVENTION
`
`[0001]
`
`1. Field of the Invention
`
`invention relates to data recording
`[0002] The present
`technique for the so-called IP or Internet telephony. More
`particularly, the invention relates to a data recording system
`for IP telephony that realizes approximately the same voice
`or speech communication as the conventional, ordinary
`telephony by the use of the Internet Protocol (IP) and the
`IP-based computer network.
`
`[0003]
`
`2. Description of the Related Art
`
`“telephony” is known as one of the telephone
`[0004]
`techniques or services that enables voice or speech commu-
`nication between telephone terminals (e.g., IP telephone
`terminals or ordinary telephone terminals) by way of an
`IP-based computer network or networks such as the Internet,
`Local Area Networks (LANs), and Wide Area Networks
`(WANs). Thus, a person can talk with another distant from
`him or her by the use of the IP telephony in a similar way
`to the ordinary telephony.
`
`[0005] With IP telephony, voice or audio data (i.e., audio
`data) to be transmitted is divided into IP packets (i.e., audio
`IP packets) and then, these packets are successively sent
`from a telephone terminal to another distant from it by way
`of an IP-based computer network. When audio data is
`transmitted using IP telephony, audio IP packets correspond-
`ing to the audio data need to be processed in real time. On
`the other hand, if audio data is transmitted as it is, it is
`impossible to ensure a required frequency bandwidth for
`data transmission. This is because the Ip-based network is of
`the so-called “best effort” type. As a result, conventionally,
`audio data is usually transmitted using the User Datagram
`Protocol (UDP) and the Realtime Transport Protocol (RTP)
`for the transport layer of the well-known OSI (Open Sys-
`tems Interconnection) reference model.
`
`[0006] Since IP telephony uses the IP protocol for data
`transmission, part of the IP packets tend to be lost during
`transmission and the packets thus lost are automatically
`resent from the telephone terminal from which the lost IP
`packets are originated. Generally,
`the loss rate of the IP
`packets during transmission varies dependent on the current
`amount of the traffic on an IP-based network. Thus, there is
`a problem the voice or speech communication quality is
`likely to deteriorate.
`
`[0007] Moreover, the amount of the traffic on an IP net-
`work fluctuates at all times and abrupt increase of the traffic
`amount is unable to be anticipated. If the fluctuation of the
`traffic amount can be controlled to an extent by a process
`such as giving the order of priority to the audio IP packets,
`the above-described problem about
`the communication
`quality deterioration may be suppressed. In this case, how-
`ever, not only the functions of routers connected to the
`network but also the entire operation of the network itself
`need to be additionally controlled. Thus, it is not realistic.
`
`[0008] Additionally, even if only the operation of the IP
`telephone terminal is controlled to give the order of priority
`to the audio IP packets, it is difficult to make sure that the
`audio data packets are transmitted through the network as
`intended.
`
`[0009] Furthermore, if the loss rate of the audio packets
`increases when the amount of traffic is large, the packet
`retransmission process and/or the congestion control process
`is/are not performed, where only the real-time process using
`the RTP protocol is carried out. Therefore, in this case, the
`speech quality deterioration becomes more conspicuous.
`
`[0010] Considering the above-described characteristics of
`IP telephony, conventionally, a function to complement the
`lost IP packets during transmission is incorporated into the
`IP telephone terminal and/or the IP telephone subscriber
`circuit of an exchange. This lost-packet complementing
`function is implemented by anticipating the audio data
`contained in a lost IP packet based on its precedent and
`subsequent audio data. Therefore, the audio data comple-
`mented by this function does not accord perfectly with that
`contained in the lost packet. Although various researches on
`the lost-packet complementing function have been con-
`ducted, it is unable to realize complete reproduction of the
`original voice or speech as long as this function is used.
`
`[0011] The complement of the lost packet is more difficult
`if the loss rate of the packets increases furthermore as the
`traffic increases. This means that in this case, the comple-
`mented data is noticeably different from the original one.
`Thus, the reproduced speech tends to include some sensible
`distortion.
`
`[0012] As explained above, when audio data is transmitted
`over the IP-based network, the quality of the reproduced
`speech is affected by the fluctuation of uncontrollable traffic.
`Thus, to keep the quality degradation and the transmission
`delay of audio data over the IP network at the same level as
`the conventional, ordinary telephony by way of the tele-
`phone lines, a control method using the TOS (Type of
`Service) field included in the header of an IP packet may be
`adopted, for example. However, in this method, high per-
`formance routers capable of interpreting the content of the
`TOS field are required over the whole IP-based network. As
`a result, this method is difficult to be adopted practically.
`
`[0013] Moreover, a voice or sound recording method on a
`magnetic tape or the like (which has been incorporated in the
`conventional
`telephone-answering machines) may be
`adopted to realize approximately the same quality degrada-
`tion and approximately the same transmission delay over the
`IP-based network as the conventional, ordinary telephony.
`Ordinary telephone-answering machines record directly the
`voice or speech generated by the handset of a telephone on
`a magnetic tape. If this direct recording method in the
`ordinary answering machine is applied to the IP telephone
`terminal, there is a possibility that the quality of reproduced
`voice or speech tends to degrade due to the loss of IP packets
`described previously. As a result, even if the voice or speech
`generated by the IP telephone terminal is directly recorded
`on a magnetic tape, the above-identified disadvantage of IP
`telephony (i.e., the complete reproduction of original voice
`or speech is impossible) is unable to be solved.
`
`SUMMARY OF THE INVENTION
`
`[0014] Accordingly, an object of the present invention is to
`provide a data recording system for
`IP telephony that
`complements perfectly the lost audio data due to loss of the
`IP packets during transmission.
`
`

`
`US 2002/0027977 A1
`
`Mar. 7, 2002
`
`[0015] Another object of the present invention is to pro-
`vide a data recording system for IP telephony that eliminates
`the necessity of the lost-packet complementing function for
`the lost audio IP packets.
`
`[0016] The above objects together with others not specifi-
`cally mentioned will become clear to those skilled in the art
`from the following description.
`
`[0017] A data recording system for IP (Internet Protocol)
`telephony according to the invention comprises;
`
`[0018]
`
`(a) an IP-based network;
`
`(b) a first telephone terminal connected to the
`[0019]
`network;
`
`the first telephone terminal being capable of
`[0020]
`transmission and reception of audio data in the
`form of IP packets, making communication using
`an IP;
`
`(c) a second telephone terminal connectable
`[0021]
`directly to the network or indirectly thereto by way
`of an exchange;
`
`terminal being
`telephone
`second
`the
`[0022]
`capable of speech communication; and
`
`[0023]
`work;
`
`(d) a recording device connected to the net-
`
`the recording device being capable of
`[0024]
`recording audio data transmitted between the first
`telephone terminal to the second telephone termi-
`nal;
`
`[0025] wherein when communication is performed
`between the first telephone terminal and the sec-
`ond telephone terminal, speech IP packets corre-
`sponding to audio data are formed and then, the
`speech IP packets thus formed are transmitted
`between the first telephone terminal and the sec-
`ond telephone terminal by way of the network in
`approximately real time; and
`
`[0026] wherein recording IP packets correspond-
`ing to the audio data are formed and then,
`the
`recording IP packets are transmitted to the record-
`ing device by way of the network in a way that
`does not cause any IP packet loss during trans-
`mission and that is not performed in real time,
`thereby recording the audio data by the recording
`device.
`
`[0027] With the data recording system according to the
`invention, the recording device connected to the IP-based
`network is provided, where the recording device is capable
`of recording the audio data transmitted between the first and
`second telephone terminals. When speech communication is
`performed between the first and second telephone terminals,
`the speech IP packets corresponding to the audio data are
`formed and then, they are transmitted between the first and
`second telephone terminals by way of the network in
`approximately real time. On the other hand, the recording IP
`packets corresponding to the audio data are formed and then,
`the recording IP packets are transmitted to the recording
`device by way of the network in the way that does not cause
`any IP packet
`loss during transmission and that
`is not
`
`performed in real time. The audio data thus transmitted is
`recorded by the recording device.
`
`[0028] Thus, communication is performed with the speech
`IP packets transmitted over the network in real time. At the
`same time as this, the audio data transmitted by the record-
`ing IP packets is recorded by the recording device, where the
`recording IP packets are not lost during transmission and the
`transmission is not carried out in real time.
`
`[0029] Accordingly, if the audio data stored in the record-
`ing device is read out for reproduction after the communi-
`cation is finished, all
`the audio data transmitted by the
`speech IP packets without IP packet loss over the network
`can be reproduced. In other words, the necessity of the
`lost-packet complementing function for the lost audio IP
`packets is eliminated, which realizes defect-free speech or
`voice communication between the first and second termi-
`nals.
`
`In a preferred embodiment of the system according
`[0030]
`to the invention, the recording IP packets are transmitted to
`the recording device using the Transmission Control Proto-
`col (TCP) for the transport layer of the OSI reference model.
`In this embodiment, the recording IP packets are transmitted
`to the recording device using the TCP that conducts error-
`recovering processes during transmission such as an auto-
`matic packet-resending process. Thus, defect-free speech/
`voice communication can be easily realized without the use
`of the lost-packet complementing function.
`
`In another preferred embodiment of the system
`[0031]
`according to the invention, the speech IP packets are trans-
`mitted over the network using the UDP and the RTP. In this
`embodiment, the speech IP packets are transmitted over the
`network using the UDP and the RTP and therefore, they are
`transmitted over the network in approximately real time like
`the conventional IP telephony. If some of the speech IP
`packets are lost during transmission, the lost IP packets are
`complemented by anticipating the audio data contained in
`the lost IP packets based on their precedent and subsequent
`audio data,
`thereby enabling the substantially real-time
`speech communication.
`
`In still another preferred embodiment of the system
`[0032]
`according to the invention, the recording device is designed
`to be recordable only when the first telephone terminal is in
`an off-hook state. In this embodiment, the recording device
`does not record the recording IP packets when the first
`telephone terminal is in an on-hook state and therefore, there
`is an additional advantage that the running cost of the system
`decreases surely.
`
`In a further preferred embodiment of the system
`[0033]
`according to the invention, the recording device starts its
`recording operation based on a recording start order emitted
`from the first telephone terminal. In this embodiment, the
`recording device starts its recording operation according to
`the intention of the user of the first telephone terminal and
`therefore, a necessary part of the communication is selec-
`tively recorded. Thus, there is an additional advantage that
`the limited volume of a recording medium of the recording
`device is efficiently used.
`
`In a still further preferred embodiment of the
`[0034]
`system according to the invention, the recording device is
`designed to finish its recording operation by an on-hook
`operation of the first telephone terminal. In this embodiment,
`
`

`
`US 2002/0027977 A1
`
`Mar. 7, 2002
`
`there is an additional advantage that the recording operation
`of the device is surely prevented in the on-hook state of the
`first telephone terminal after the communication is finished.
`[0035]
`In a still further preferred embodiment of the
`system according to the invention,
`the recording device
`finishes its recording operation based on a recording stop
`order emitted from the first
`telephone terminal.
`In this
`embodiment,
`the recording device finishes its recording
`operation according to the intention of the user of the first
`telephone terminal and therefore, a necessary part of the
`communication is selectively recorded. Thus, there is an
`additional advantage that the limited volume of a recording
`medium of the recording device is efficiently used.
`[0036]
`In a still further preferred embodiment of the
`system according to the invention, the recording device is
`designed to record in such a way that the speech IP packets
`from the first telephone terminal and those from the second
`telephone terminal or the exchange are independent from
`each other.
`In this embodiment,
`there is an additional
`advantage that the audio data from the first terminal and that
`from the second terminal or the exchange can be reproduced
`separately. Thus, even if the audio data from the first
`terminal and that from the second terminal or the exchange
`are overlapped and difficult to be heard, they can be clearly
`heard by reproducing them separately.
`the recording
`[0037]
`In this embodiment, preferably,
`device is designed to record a real time value of a first one
`of the recording IP packers from the first telephone terminal
`and a real time value of a first one of the recording IP packets
`from the second telephone terminal or the exchange. In this
`case, there is an additional advantage that the time sequence
`of the recorded audio data from the first terminal and the
`
`time sequence of the recorded audio data from the second
`terminal or the exchange can be identified separately.
`[0038]
`In this case, preferably,
`the recording device is
`designed to reproduce the recorded audio data from the first
`telephone terminal and the recorded audio data from the
`second telephone terminal or the exchange according to their
`real time sequence, respectively. In this case, there is an
`additional advantage that the voice or speech communica-
`tion between the first and second telephone terminals can be
`entirely reproduced with the recording device.
`[0039]
`In a still further preferred embodiment of the
`system according to the invention, the recording device is
`formed by an information-processing device (e.g., a per-
`sonal computer or server computer) connected to the net-
`work. In this embodiment, there is an additional advantage
`that the audio data is easily recorded and easily reproduced,
`because a storage device incorporated into a computer
`serving as the recording device can be used for recording
`and reproduction of the audio data.
`[0040]
`In a still further preferred embodiment of the
`system according to the invention, the first telephone termi-
`nal and the recording device are united together. In this
`embodiment,
`there is an additional advantage that
`the
`recording and reproducing operations of the audio data
`corresponding to the recording IP packets are easily per-
`formed if the user operates the first telephone terminal.
`There is another additional advantage that if the first tele-
`phone terminal is formed by software running on an infor-
`mation-processing device,
`the recording device can be
`formed by a storage device of the information-processing
`device.
`
`the second tele-
`In the system of the invention,
`[0041]
`phone terminal may be connected indirectly to the network
`by way of the exchange. In this case, the second telephone
`terminal is capable of voice or speech communication with
`the first telephone terminal by way of the exchange and the
`network. On the other hand, the second telephone terminal
`may be connected directly to the network. In this case, the
`second telephone terminal is capable of transmission and
`reception of the audio data in the form of IP packets, making
`voice or speech communication using the IP.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`In order that the present invention may be readily
`[0042]
`carried into effect, it will now be described with reference to
`the accompanying drawings.
`
`[0043] FIG. 1 is a functional block diagram showing the
`configuration of a data recording system for IP telephony
`according to a first embodiment of the invention.
`
`[0044] FIG. 2 is a functional block diagram showing the
`configuration of the IP telephone terminal used in the system
`according to the first embodiment of FIG. 1.
`
`[0045] FIG. 3 is a functional block diagram showing the
`configuration of the IP subscriber circuit used in the system
`according to the first embodiment of FIG. 1.
`
`[0046] FIG. 4 is a schematic diagram showing the trans-
`mission of the IP packets among the telephone terminal, the
`subscriber circuit of the exchange, and the recording com-
`puter in the system according to the first embodiment of
`FIG. 1.
`
`[0047] FIG. 5 is a schematic diagram showing the state or
`form of the voice and time data recorded in the storage
`device of the recording computer used in the system accord-
`ing to the first embodiment of FIG. 1.
`
`sequence diagram showing the
`a
`6 is
`[0048] FIG.
`sequence of the whole operation of the system according to
`the first embodiment of FIG. 1.
`
`sequence diagram showing the
`a
`[0049] FIG. 7 is
`sequence of the operation of the system according to the first
`embodiment of FIG. 1, where the handset of the terminal is
`turned into the on-hook state in the recording mode.
`
`[0050] FIG. 8 is a flowchart showing the flow of the
`operation of the system according to the first embodiment of
`FIG. 1 in the reproduction mode.
`
`[0051] FIG. 9 is a schematic diagram showing the repro-
`duction timing of the voice data corresponding to the
`respective IP packets in the system according to the first
`embodiment of FIG. 1 in the reproduction mode.
`
`[0052] FIG. 10 is a functional block diagram showing the
`configuration of a personal computer serving as the IP
`telephone terminal and the recording device in a data
`recording system for the IP telephone according to a second
`embodiment of the invention.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`[0053] Preferred embodiments of the present invention
`will be described in detail below while referring to the
`drawings attached.
`
`

`
`US 2002/0027977 A1
`
`Mar. 7, 2002
`
`First Embodiment
`
`[0054] As shown in FIG. 1, a data recording system 10 for
`IP telephony according to a first embodiment comprises two
`IP telephone terminals 100 and 100A, an exchange 200, an
`administrative server 300, a personal computer 400 for data
`recording, and an IP-based network 500. An ordinary tele-
`phone terminal 211 is connected to the network 500 by way
`of the exchange 200. Needless to say, other ordinary tele-
`phone terminals (not shown) are connected to the network
`500 by way of the exchange 200. However, only one
`terminal 211 is shown in FIG. 2 for simplification.
`
`[0055] Although two IP telephone terminals 100 and 100A
`and one recording computer 400 are shown in FIG. 1 for the
`sake of simplification, any other IP telephone terminal or
`terminals and/or any other recording computer or computers
`may be added to the configuration of FIG. 1 as necessary.
`
`[0056] The IP-based network 500 is formed by a computer
`network or a group of computer networks using the Internet
`Protocol (e.g., the global Internet or private computer net-
`works such as LANs and WANs).
`
`[0057] The telephone terminal 100 is a terminal for real-
`izing IP telephony with an interface for IP packet transmis-
`sion. The terminal 100 has a specific telephone number like
`conventional, ordinary telephones. The terminal has the
`configuration shown in FIG. 2.
`
`[0058] The IP telephone terminal 100A has the same
`configuration and the same operation as those of the terminal
`100. Therefore, the explanation about the terminal 100 is
`mainly made below.
`
`[0059] As shown in FIG. 2, the terminal 100 comprises a
`handset (a transmitter/receiver unit) 110, a transmitter sec-
`tion 120, a receiver section 130, a memory 140, and an
`interface 150. The interface is used for interconnection of
`the terminal 100 to the IP-based network 500.
`
`If the user lifts the handset 110 from the body of the
`[0060]
`terminal 100 by the hand for speech or talk, the terminal 100
`is turned into the off-hook state where communication is
`
`possible. Thereafter, if the user put the handset 110 on the
`body of the terminal 100 at the end of speech or talk, the
`terminal 100 is returned to the on-hook state where com-
`
`munication is impossible.
`
`[0061] The handset 110 has a microphone 111 and a
`speaker 112. The microphone 111 collects the user’s voice
`(or sound) at the terminal 100 and converts it into an electric
`audio signal. The electric audio signal thus formed is sent to
`the transmitter section 120 and then, sent out to the network
`500 by way of the interface 150 in the form of IP packet. The
`speaker 112 emits voice (or sound) from the person the user
`of the terminal 100 is speaking to by reconverting its
`electronic audio signal into the voice (or sound). The electric
`audio signal thus reproduced is sent to the interface 150 and
`the network 500 in the form of IP packets from the opponent
`of the user and then, it is further sent to the speaker 112
`through the receiver section 130, emitting the opponent’s
`voice.
`
`[0062] The telephone terminal 100 is usually configured
`by the combination of specific hardware (e.g., a sound card
`and a microphone) and a software program operable on a
`personal computer (PC) providing a telephony function.
`
`the terminal 100 may have a
`However, needless to say,
`configuration like the ordinary telephone configuration, if
`possible.
`
`[0063] The operation of the transmitter section 120 during
`the off-hook state is as follows.
`
`[0064] The telephone terminal 100 has the “recording
`mode” where the speech or talk is recorded by the recording
`computer 400 (i.e., the recording operation is active) and the
`“non-recording mode” where the speech or talk is not
`recorded by the computer 400 (i.e., the recording operation
`is inactive).
`
`In the non-recording mode, the transmitter section
`[0065]
`120 generates IP packets corresponding to the electric audio
`signal generated by the microphone 111 on the handset 110
`(i.e., IP packets corresponding to the user’s voice or audio
`data) and transmits them to the outside of the terminal 100
`(i.e., the network 500) by way of the interface 150. At this
`time, these IP packets are sent to the network 500 using the
`UDT and the RTP for the transport layer of the OSI reference
`model. The IP packets thus sent from the terminal 100 are
`further sent to the subscriber circuit 220 of the exchange 200
`by way of the network 500.
`
`[0066] The IP packets corresponding to the user’s voice
`data sent from the terminal 100 are termed the “speech IP
`packets”. The user’s voice data may include any sound data
`other than the user’s voice.
`
`In the recording mode, like the operation of the
`[0067]
`non-recording mode, the transmitter section 120 generates
`the speech IP packets corresponding to the user’s voice data
`and transmits them to the subscriber circuit 220 or the
`
`exchange 200 by way of the network 500. At the same time
`as this,
`the section 120 stores the data of the speech IP
`packets in the memory 140. Thereafter, the section 120 reads
`out
`the data of the packets from the memory 140 and
`transmits them to the outside of the terminal 100 using the
`TCP (not the UDP and the RTP) for the transport layer of the
`OSI reference model. These packets thus transmitted from
`the section 120 using the TCP are sent to the recording
`computer 400 by way of the network 500. These IP packets
`are termed the “recording IP packets”, because they are
`formed and transmitted for recording in the memory 140.
`
`[0068] The operation of the receiver section 130 during
`the off-hook state is the same in both the non-recording
`mode and the recording mode. The section 130 receives the
`IP packets (i.e., the speech IP packets) that are sent from the
`subscriber circuit 220 of the exchange 200 by way of the
`network 500 and the interface 150. The speech IP packets
`correspond to the voice data of the user of a distant tele-
`phone terminal from the terminal 100. The section 130
`transmits the speech IP packets thus received to the speaker
`112 on the handset 110, reproducing the voice of the person
`the user is talking with at the distant terminal.
`
`[0069] The telephone terminal 100 further comprises a
`recording button 160. If the user operates the button 160, the
`recording mode and the non-recording mode of the trans-
`mitter section 120 are alternately switched or activated and
`at the same time, a specific IP packet for instructing the start
`and end of the recording operation of the computer 400 is
`transmitted toward the computer 400. The button 160 is, for
`example, of the toggle type. If the user operates the button
`160 for the first time, the telephone terminal 100 is turned
`
`

`
`US 2002/0027977 A1
`
`Mar. 7, 2002
`
`into the recording mode and then, it emits the instruction
`packet for starting the recording operation to the computer
`400. If the user operates the button 160 for the second time,
`the terminal 100 is returned to the non-recording mode and
`then, it emits the instruction packet for stopping the record-
`ing operation to the computer 400. The same operation
`sequence is repeated if the user operates the button 160 in
`the same way later.
`
`[0070] When the terminal 100 is in the recording mode in
`the off-hook state, a lamp (not shown) provided for the
`button 160 is turned on. This is to show the user that the
`
`speech is recordable or not. Preferably, the color of the lamp
`varies between the recording and non-recording modes. For
`example, the button 160 is formed in such a way that the
`lamp emits “green” light in the non-recording mode while it
`emits “red” light in the recording mode.
`
`100 is
`terminal
`telephone
`the
`[0071] Additionally,
`designed to enter the non-recording mode at the start of
`operation (i.e., at the start of speech or communication).
`
`[0072] FIG. 4 shows the flow of the speech and recording
`IP packets among the terminal 100, the subscriber circuit
`220, and the recording computer 400.
`
`In the non-recording mode, as indicated by the
`[0073]
`arrow A, the telephone terminal 100 generates the “speech
`IP packets” corresponding to the user’s voice and transmits
`them to the exchange 200 by way of the network 500 using
`the UDT and the RTP for the transport layer of the OSI
`reference model. In t