BILLING SYSTEM AND METHOD FOR USE IN INTERNET PHONE Technical Field The present invention relates to a billing system and method for use in an internet phone, and a message format for the billing system and method in which a bill processor acting as an electronic purse is added to the internet phone (hereinafter, also referred to as"IP phone"), in which the amount of a user's service charge that the bill processor of the IP phone collect is stored in a gatekeeper, and in which a program allowing the service charge to be paid to the gatekeeper is installed in a separate EEPROM.

Background Art In general, mobile phones refer to cellular phones or PCS phones, and a basic communication system for such phones to be connected to each other to enable a telephone call from one mobile phone to another, as shown, Fig. 1, comprises a telecommunication service company 40, a mobile telephone 50 used by subscribers who join the telecommunication service company 40 as members and communicate with each other, and a packet switched network 31 adapted to allow the telecommunication service company 40 to be connected to another telecommunication service company or a wired communication network.

Fig. 2 is a perspective view illustrating a typical web videophone which can be used according to the prior art.

Meanwhile, a web videophone enables a calling party to speak by telephone face to face with a called party through a video screen. Such a web videophone, as shown in Fig. 2, includes a telephone body 11 having a key input section 12 installed thereto, a key board 13

mounted to the telephone body 11, and a display unit 18 mounted at any desirable position of the telephone body 11. An image pickup device or a charge-coupled device (CCD) 19 is disposed at the middle portion of the upper edge of the display unit 18. Also, mounted to the one side of the top surface of the telephone body 11 an IC card recognizing (reading) section 20 for inserting an IC card 21 having a user ID stored in an IC chip thereof to identify a web videophone user's ID.

Fig. 3 is a block diagram illustrating the construction of the typical web videophone of Fig. 2.

Referring to Fig. 3, there is shown the web videophone 100 comprising an analog/digital converter A/D 22, a control section 23, a display unit 18, an interface I/F 24, and a modem 6. The analog/digital converter A/D 22 is adapted to convert an image output from the image pickup device or charge coupled device (CCD) 19 into a digital signal. The control section 23 is adapted to control the digital-converted video data.

The display unit 18 is adapted to convert the video data from the control section 23 into an analog signal to display the converted analog video signal thereon. The interface I/F 24 is adapted to interface the digital data outputted from the control section 23 to conform to a modem standard. And, the modem 6 is adapted to convert the interfaced digital data outputted from the interface I/F 24 in series or parallel to transmit it through the interface I/F 24 by way of a private (dedicated) line 5.

A reference numeral 30 denotes an Integrated Service Digital Network (hereinafter, referred to as"ISDN"), and a reference numeral 31 denotes an Internet network.

Fig. 4 is a block diagram illustrating a communication network system to which the typical web videophone is applied according to the prior art.

Referring to Fig. 4, there is shown the

communication network system comprising a plurality of web videophones 100, a distributor HUB 110, a router 120, a Wide Area Network (WAN) 32, and a server 200. The plurality of web videophones 100 are connected to each other through a local area network (LAN) as shown in Fig. 3. The distributor HUB 110 is adapted to distribute the plurality of web videophone 100, respectively. The router 120 is adapted to connect a plurality of separated communication networks to each other between the distributor HUB 110 and a digital service unit (DSU) 130. The Wide Area Network (WAN) 32 is adapted to allow the digital service unit (DSU) 130 to be connected to the Internet 31. And, the server 200 is connected to the HUB 110 for providing a communication service to enable web videophone calls from one subscriber to another through the Internet network 31. A reference numeral 140 denotes an Internet network-accessing device which comprises the distributor HUB 110, the router 120, and the digital service unit (DSU) 130. Also, a reference numeral 150 denotes a web videophone system comprising the Internet network-accessing device 140, the plurality of web videophones 100, and the server 200.

Fig. 5 is a schematic block diagram illustrating a controlled information flow between a plurality of web videophones 100 and a server 200 in the communication network system of Fig. 4.

Referring to Fig. 5, a system for controlling the information flow comprises a server 200, a plurality of web videophones 100 which have subscribed for the server 200, and personal computers (PCs) 300. The server 200 includes a gatekeeper or directory server 210, a web server 220, and a data base server 300. In this case, when a certain subscriber of the web videophone 100 inserts the IC card 21 shown in Fig. 2 into the IC card recognizing section 20, the IC card recognizing section

20 reads the insertion of the IC card 21 to transfer the subscriber's ID to the directory server 210 of the server 200. At this time, when the directory server 210 requests the subscriber's password, etc., the card recognizing section 20 of the web videophone 100 transfers the password information to the directory server 210 through the IC card 21 to identify whether or not the subscriber is a valid member. The directory server 210 manages the operation status (log-on, line's busy, standby, etc.) of the web videophone used all over the world, and updates subscriber information in a two- minute cycle (not limited particularly to a specific cycle) to inform the web videophone 100 of the updated information. That is, the web server 220 functions as a server based on information search results from the gatekeeper 210, and a desired data is read on the basis of data of the data base server 230, if necessary, so that the gatekeeper 210 can perform its own function in real time.

Fig. 6 is a block diagram illustrating a wireless communication network system in which the web videophone is connected to a typical wireless mobile phone network to allow telephone calls between the mobile phone and the web videophone according to the prior art.

Referring to Fig. 6, a mobile phone 50 or a terminal locates another mobile phone through a telecommunication service company 40 to communicate with the located other mobile phone. The telecommunication service company 40 comprises a Base Transceiver Station (BTS) 41 adapted to provide an environment to communicate with the mobile phone 50 by using a protocol according to Interleaf Standard-95 (IS-95) at a wireless cell site ("region"), a Base Station Controller (BSC) 42 adapted to control a wireless link and a wired link through each base transceiver station (BTS) 41 and

perform a handoff function to allow a subscriber to continuously maintain a telephone call even when the subscriber's mobile phone communicating with a base transceiver station enters another base transceiver station's cell site, a Mobile Switching Center (MSC) 43 adapted to switch each base station controller (BSC) 42 and totally manage each Base Station Controller (BSC) 42, and a network converter 44 such as an Inter Working Function (hereinafter, referred to as"IWF") adapted to convert a signal to be transmitted from the mobile phone 50 to the packet switched network 31 to allow the mobile phone 50 to access the packet switched network 31 belonging to the Internet network through a switching function of the mobile switching center (MSC) 43.

Also, a typical router 140 or an Internet network accessing device is connected to the packet switched network 31 which in turn is connected to a videophone system enabling audio (e. g., voice) and video communications between the web videophones 100 through a gatekeeper 210 for guaranteeing a call quality state when there is an interconnection between the web videophones 100 through the Internet accessing device 140. In the drawing, several web videophones are shown, but whenever a new subscriber joins the videophone system, the new subscriber's web videophone may be connected additionally to the videophone system. This videophone system enables a subscriber of the web videophone 100 to speak by telephone face to face with another subscriber of a web videophone 100 through a video screen, but enables only voice communication between a subscriber of the mobile phone 50 and the subscriber of the web videophone 100, which is disadvantageous to a user using an expensive web videophone. However, for such a web videophone, when the web videophone is produced except a video part to

achieve the reduction of the cost price, it can also be used as a general internet phone. For this reason, the web videophone is hereinafter referred to as an internet phone.

Several kinds of cashless financial transaction services are available conventionally.

These include credit cards or debit cards which customers may use with a wide range of retailers. Each transaction is accompanied by the provision of customer account details required for the actual transfer of funds between the specific customers and the specific retailers.

Another form of cashless card system is a prepayment card system, in which a card is purchased prior to a series of transactions and a value record recorded on it is appropriately decremented on each transaction. A phone card is an example of the prepayment card.

Such prior systems are inflexible and are no general substitute for cash in low value high volume transactions. Various proposals have been put forward to allow the interchange of money values between "electronic purses". For example, United States Patent No. 4,839,504 (Casio Computer Co., Ltd.) discloses a system where a user is able to load money onto an integrated circuit (IC) card, otherwise known as a smart card, by communication with his bank. At the bank the same value is applied to a separate IC account set up for the user. Purchases can be made by transfer of money values from the IC card to retailer equipment off-line from the bank. Each transaction requires transmission to the retailer and retention by him of details which include the purchaser's identity. Ultimately, in claiming funds from the bank the retailer presents a list of transaction details and there is account

reconciliation to allow the IC account of the appropriate purchaser to be adjusted.

Procedures which, as above, require ultimate account reconciliation for every transaction are attended by two disadvantages. The first is practical.

The storing, transmitting and reconciling of purchaser details for every transaction places an impossible burden on equipment if all cash type transactions are contemplated. Processing all such transactions efficiently in an acceptable time is not possible, even with the most modern equipment. The second objection is social. The anonymity of cash would be lost and potential would exist for details of personal spending habits to be derived.

For this purpose, International Publication Number W091/16691 discloses a value transfer system based on an electronic purse concept which secures a customer against outflow of his own personal information details.

Such a system provides a practical solution to the problem by providing a framework suitable for cashless small value high volume transactions.

The value transfer system proposed in the above patent has a computer; a plurality of electronic purses; exchange devices whereby purses may communicate with each other to transfer value in transactions which are off-line from the computer; draw-down means for loading purses with value under control of the computer; redemption means for redeeming value from purses under control of the computer; a value meter; one or more of said purses being bulk purses which are capable of having value loaded and redeemed via the value meter, the value meter recording one or more float value records whereby the net value released to the bulk purse or purses may be derived, the net value being the difference between the total of values drawn down to the

bulk purse or purses and the total of values redeemed from the bulk purse or purses, the float value record being non-specific with regard to individual draw-down and redemptions.

The value meter may have an interface whereby the float value record may be adjusted on command so as to create or destroy value within the bulk purse or purses.

Further, there is provided, in each purse, storage means which stores a purse value record which is accumulative and, in each purse or associated exchange device, a microprocessor, transactions being conducted between purse pairs, one of which, the sending purse, sends value and the other of which, the receiving purse, receives value, the microprocessors being programmed so that in each off-line transaction the purse value record in the sending purse is decreased by a chosen and variable transaction value and the purse value record in the receiving purse is increased by the same transaction value.

By providing a float value record which is non- specific anonymity is ensured and reconciliation with customer accounts for all subsequent purse-to-purse transactions is unnecessary.

Fig. 7 is a schematic view illustrating a banking computer system according to the prior art.

Referring to Fig. 7, there are shown three clearing banks 1,2 and 3 with respective computers la, 2a and 3a. The computers have files containing account details of the banks'consumer and retailer customers.

Each computer also has a value meter lb, 2b and 3b which shows a float value record. The actual funds represented by the non-specific float value records may reside in one or more of banks 1,2 and 3, or elsewhere.

Each bank has a bulk purse lc, 2c and 3c which is connected to the respective value meter and which has a

memory with a purse value record. Terminals 5 are connected by telephone selectively to computers of banks 1,2 and 3. Typically, terminals 5 may be home computer terminals or terminals available in public places.

Consumers have electronic purses in the form of IC card 6. These cards have microprocessors and memories.

In the memory of each card is stored a purse value record 7. The cards have contacts 8, whereby the cards can interact with terminals 5 via card readers 9.

By making appropriate requests at the keyboard of the terminal, a consumer may be connected to the computer of his bank 1,2 and 3 and may request a value record to be loaded to his purse. If the bank authorizes the request, the bulk purse is instructed to institute a draw-down of value to load purse value record 7 with the value requested. The card is now ready for use.

Further, electronic purses are contained in terminals 10,11 which are equipped with IC card readers, located at different points-of-sale. To use his card the consumer presents it to the retailer where it is inserted into the reader 9. The required value of the transaction is keyed in and by agreement the total held in the purse value record of the purse 6 is reduced by the amount of the transaction. The purse value record of the purse held within the terminal 10 or 11 is increased by the same transaction value. The consumer takes his goods and is free to use the card up to the total held in the purse value record of his purse in other retailer's equipment.

Periodically a retailer may redeem value represented by the purse value record held in the purse of his terminal 10 or 11, irrespective of the consumer's identities and without presenting any details of the individual transactions that have given rise to the total accumulated value. This may be done by connecting

the terminal 10 or 11 to the retailer's bank 1,2 and 3 as appropriate and requesting a redemption of value. The bank's computer then instructs a redemption transaction which accepts value from the terminal purse. The bank computer credits the retailer's account with funds. The value meters form the basis for allowing control of the total amount of value in circulation in all the purses and for apportioning, on an agreed basis, funds representing'the total value.

The bulk purses lc, 2c and 3c differ from the other purses in being capable of having value loaded and redeemed via the value meter, as well as by purse to purse transactions. In all other respects the purses are technically similar, it being understood in particular that the same cryptographic techniques for bulk purse to other purse transactions (on-line) used are the same as for off-line transactions.

Fig. 8a shows a card reader according to one embodiment of the prior art in the form of a pocket exchange device.

Referring to Fig. 8a, this device PEC is battery powered or solar powered, and has an LCD screen A15 and IC card reader A16. The consumer's card is inserted in the card reader A16 and it may then be interrogated by means of keys A17 to A21. A key A17 allows the user to scroll through log entries and balances resident on the card, accessed via keys 19 and 20. Keys 18 and 21 allow interchange between two cards, via an intermediate store within the device.

Fig. 8b is a block diagram illustrating the construction of a billing system for an internet phone system to which an existing electronic purse is applied according to the prior art.

As shown in Fig. 8b, where such electronic money is applied to an internet phone, in an internet phone

system employing an IP phone 160 which is an existing internet phone and a call controlling gatekeeper G/K 210, a separate bill processor 170 serving as an electronic purse is connected to the IP phone 160 using an interface RS-232C. Also, after newly adding another to an existing line of the IP phone 160, a bill server 180 is built through the added line to perform protocol X. 25 for claiming a customer's calling service charge or a charge for call services, while the bill server 180 is connected to a bank via a dedicated line VAN.

Accordingly, since the internet phone adopts a dynamic IP scheme, interruption acceptable time between telephone calls is very short (for example, within one second). However, there has been a problem that since a few seconds (for example, four to five seconds) is required to perform protocol X. 25 according to a demand for payment of the service charge and an authentication of the bill processor 170 and the bill server 180, such a prior billing system is not suitable for an internet phone.

That is, this conventional prior billing system has a limitation in applying to an internet phone system in which the service time for each call service is calculated and an IP address and an internet phone number are allocated to a gatekeeper even during the telephone call to allow an internet phone and a general telephone to communicate with each other, and in which the interval between transmission and reception of a signal by a calling party and a called party required for the connection of a call is restricted (as long as a response for a call reaches one side of two parties within the very short time, for example, one second, the call connection can be maintained).

Disclosure of the Invention

Therefore, the present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to a billing device and method for use in an internet (IP) phone in which a bill processor acting as an electronic purse is added to an IP phone of a user, and the IP phone communicates with another IP phone or makes a real-time payment of the user's service charge to a gatekeeper under a command of a control section.

According to an aspect of the present invention, there is provided a billing system for use with an internet (IP) phone, comprising: a plurality of IP phones, each having a bill processor included integrally and internally therein in such a fashion that the bill processor is connected to a control section through an interface, the bill processor serving as an electronic purse; and a gatekeeper connected to the plurality of IP phones through a communication network, the gatekeeper being adapted to store a user's service charge collected from the bill processor therein, the gatekeeper including: a call control section adapted to control a call to enable a telephone call between two corresponding IP phones of the plurality of IP phones, the call control section having a call processing section and an additional servicing section; a billing section connected to a bank through a private line, the billing section being adapted to demand a payment of the user's service charge from the bill processor through the additional servicing section so as to collect the service charge from the bill processor; and a calling information-generating section adapted to generate information about a call service, thereby

performing a combined call processing and billing function with only an existing communication line for the internet phone.

Preferably, the gatekeeper further includes a plurality of data base sections each adapted to store and update data of an associated one of the call processing section of the call control section, the calling information-generating section and the billing section.

According to another aspect of the present invention, there is also provided a billing method for use with an internet (IP) phone in a billing system including a plurality of IP phones (web phones) and a gatekeeper for storing an IP address and a user's IP phone number therein to allow a telephone call between IP phones or between an IP phone and a general telephone, the comprising the steps of: adding a bill processor acting as an electronic purse and an EEPROM to the IP phone, the bill processor and the EEPROM being adapted to communicate with a control section; allowing the gatekeeper to control a call connection between the IP phones, and to, in real time, collect a user's phone service charge for a call service from the bill processor in such a fashion that the service charge is withdrawn from the bill processor within the IP phone and stored in a memory section acting as an internal electronic purse installing a program allowing the service charge to be paid to the gatekeeper in the EEPROM of the IP phone ; allowing the program stored in the EEPROM to analyze whether a command of the control section is a call service or a phone service charge for the call service; and

allowing the program in the EEPROM to produce a service charge related message with the gatekeeper if the command is the service charge.

According to another aspect of the present invention, there is also provided a message format for use in a billing system including a plurality of IP phones and a gatekeeper, the message format being constructed to simultaneously perform an existing call controlling function and a communication protocol (X. 25) associated with a demand of payment of a user's service charge between the IP phone and the gatekeeper, and to add an actual service charge information to a header portion of the message format.

According to another aspect of the present invention, there is also provided a billing control method in an internet (IP) phone (IP) phone performing a call service and a billing related function simultaneously, comprising the steps of: allowing the EEPROM to request a program portion (Packet Tunneling, Card Reader) for processing the message for each format to process the message (Analysis), to start a timer (T1), to produce its result (Produce), to wait for an arrival of the result from each event processor (Packet Tunneling, Card Reader) (Wait) when a message (Packet Analysis. req) from the control section reaches the EEPROM (Arrival) in an initial state (Idle) in which a call service related event (the results of calculated service charges and the request for the filling of the amount) incoming from the control section (Phone_process) is processed; allowing the EEPROM to inform the control section of the time out (Report) and to convert the state of the EEPROM to another idle state if the result does not reach the EEPROM even after the lapse of the time set in the timer (Time Out) ; and

allowing the EEPROM to send the result to the phone processor (Send Report) and to convert the state thereof to the idle state if the result from the event processor reaches the EEPROM (Response).

According to the present invention, a bill processor acting as an electronic purse is added to the internet phone, the amount of a user's service charge that the bill processor of the IP phone collects is stored in a gatekeeper, and a program allowing the service charge to be paid to the gatekeeper is installed in a separate EEPROM.

Brief Description of the Drawings The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which: Fig. 1 is a schematic block diagram illustrating a wireless communication network system of a telecommunication service company for use with a typical mobile telephone according to the prior art; Fig. 2 is a perspective view illustrating a typical web videophone which can be used according to the prior art ; Fig. 3 is a block diagram illustrating the construction of the typical web videophone according to the prior art ; Fig. 4 is a block diagram illustrating a communication network system to which the typical web videophone is applied according to the prior art ; Fig. 5 is a block diagram illustrating a concrete signal flow between a plurality of web videophones and a server in the communication network system of Fig. 4; Fig. 6 is a block diagram illustrating a wireless

communication network system implemented to allow a telephone conversation between a typical mobile phone and the web videophone according to the prior art; Fig. 7 is a schematic view illustrating a typical value transfer system according to the prior art; Fig. 8a shows one possible embodiment of typical card reading devices according to one embodiment of the prior art; Fig. 8b is a block diagram illustrating the construction of a billing system for use with an internet phone to which an existing electronic purse is applied according to the prior art; Fig. 9a is a block diagram illustrating the construction of internet phone according to the present invention; Fig. 9b is a block diagram illustrating the construction of a billing system for use with an internet phone according to the present invention ; Fig. 10 is a block diagram illustrating interconnection between a bill processor and a control section shown in Figs. 9a and 9b.

Fig. lla is a block diagram illustrating the construction of a gatekeeper according to the present invention ; Fig. llb is a schematic view illustrating a signal flow for processing the billing method according to the present invention; Fig. 12a is a packet tunneling message format used in the present invention; Fig. 12b is a table illustrating a code division of a packet used in Fig. 12a; Fig. 13 is a schematic diagram illustrating a state of packet analysis for implementing the present invention; Fig. 14 is a block diagram illustrating a flow of

packet analysis for implementing the present invention ; Fig. 15 is a flow chart illustrating the process routine for explaining a billing method according to the present invention; and Fig. 16 is a schematic block diagram illustrating the entire construction of a communication network system for implementing a billing system according to the present invention.

Best Mode for Carrying Out the Invention Reference will now be made in detail to the preferred embodiments of the present invention.

Fig. 9a is a block diagram illustrating the construction of internet phone according to the present invention.

Referring to Fig. 9a, there is shown an internet (IP) phone 300 comprising an analog/digital converter A/D 22, a control section 23, a display unit 18, an interface I/F 24, and a modem 6. The analog/digital converter A/D 22 is adapted to convert an image output from the image pickup device or charge coupled device (CCD) 19 into a digital signal. The control section 23 is adapted to control the digital-converted video data.

The display unit 18 is adapted to convert the video data from the control section 23 into an analog signal to display the converted analog video signal thereon. The interface I/F 24 is adapted to interface the digital data outputted from the control section 23 to conform to a modem standard. And, the modem 6 is adapted to convert the interfaced digital data outputted from the interface I/F 24 in series or parallel to transmit it through the interface I/F 24 by way of a private (dedicated) line 5.

A reference numeral 301 denotes an EEPROM having a program for analyzing and generating a user's service charge according to the use of an internet phone

internally included therein. A reference numeral 170 denotes a bill processor for collecting a user's service charge. And a reference numeral 302 denotes an interface for allowing the bill processor 170 and the control section 23 to communicate with each other. The control section 23 also includes an algorithm for controlling the communication between the bill processor 170 and the EEPROM 301, and the processing of the user's service charge using the EEPROM 301. In this case, the internet phone 300 may be constructed in such a fashion that the image pickup device or charge coupled device (CCD) 19 and the analog-digital (A/D) converter 22 are eliminated from the internet phone 300.

Fig. 9b is a block diagram illustrating the construction of a billing system for use with an internet phone according to the present invention.

Referring to Fig. 9b, there is shown a billing system including a plurality of IP phones 300 and a gatekeeper 400. The IP phone 300 has a bill processor 170 serving as an electronic purse included integrally and internally therein in such a fashion that the bill processor 170 is connected to a control section 23 through an interface 302. The gatekeeper 400 includes a call control section 410, a billing section 420 and a calling information-generating section, and is connected to the IP phone 300 through a communication network. The control section 410 controls a call to enable a telephone call between two telephones such as IP phones 300, etc., according to an existing call service method.

The billing section 420 is connected to a bank 1 through a private line VAN. Consequently, the billing system of the present invention allows a combined call processing and billing function to be performed with only an existing communication line for the internet phone.

Fig. 10 is a block diagram illustrating an

interconnection system in which the bill processor 170 and the control section 23 are connected with each other through the interface 302 shown in Figs. 9a and 9b.

Referring to Fig. 10, the interface 302 employs a typical interface RS-232C. The control section 23 and the interface 302 are connected with each other through an address bus 23-1 and a data bus.

Fig. lla is a block diagram illustrating the construction of the gatekeeper 400 used in the present invention.

Referring to Fig. lla, the call control section 410 of the gatekeeper 400 includes a call processing section 411 and an additional servicing section 412. The billing section 420 demands a payment of the user's service charge from the bill processor 170 through the additional servicing section 412. The calling information-generating section 430 generates information about a call service. The gatekeeper 400 also includes a call control data base (DB) 413 for storing and updating data of the call processing section 411, a billing data base (DB) 423 for storing and updating data of the billing section 420, and a calling information- generating data base (DB) 423. That is, the gatekeeper 400 of the present invention has been implemented by adding the additional servicing section 412, the billing section 420 and the calling information-generating section 430 to a gatekeeper having only the control section 410 included therein according to the prior art.

Fig. llb is a schematic view illustrating a signal flow for performing the billing operation as shown in Fig. lla according to the present invention.

Referring Fig. llb, first, when the IP phone 300 requests a registration from the gatekeeper 400, the call control section 410 of the gatekeeper 400 transmits the results (RCF (identification of the registration),

RRJ (rejection of the registration)) of identification of the registration to the IP phone 300.

Next, when the IP phone 300 requests a telephone call service from the gatekeeper 400, it sends a counterpart's telephone number to the control section 410. At this time, the call control section 410 determines the position of the counterpart's terminal and sends a message (payRate. req) to the billing section 420 of the gatekeeper 400 to see information about a calling service charge per second for each call service.

At this time, when the call control section 410 sends information about the positions of a calling party and a called party to the billing section 420, the billing section 420 calculates the calling service charge per second based on the information about the positions to send the result of calculation of the service charge per second to the control section 410 (payRate. res).

The control section 410 of the gatekeeper 400 sends a signal ACF indicative of identification of authentication of the call service or a signal ARJ indicative of the rejection of authentication of the call service to the IP phone 300 while sending the service charge-per-second information message (Facility (payInfo. ind)) to the IP phone 300.

When the IP phone 300 transmits a message (SETUP) to call control section 410 of the gatekeeper 400 to try to establish connection of a call, the call control section 410 sends a message (CONNECT) to the IP phone 300, and at the same time, sends the calling party's telephone number and the called party's telephone number, a call service starting time to the calling information-generating section 430 which, in turn, generates a message (CDR: Call Detail Record) (Connectlnfo).

When the call service terminates, the IP phone 300

sends a call connection release-requesting signal DRQ to the call control section 410 to request a release of the call connection, the call control section 410 sends a call connection release-identifying signal DCF to the IP phone 300 to identify the request of the release of the call connection while informing a call service ending time of the calling information-generating section 430 to allow the calling information-generating section 430 to complete the message (CDR). Also, the call control section 410 sends a call service ending signal to the billing section 420 of the gatekeeper 400 to allow the billing section 420 to add a present calling service charge of the calling party to an existing accumulated charge for previous call services (accum. req).

At this time, when an addition of the present service charge to the accumulated one is completed, the billing section 420 informs the call control section 410 of the result of the accumulation of service charges (accum. res) and the call control section 410 sends a message (Facility (payInfo. ind) to the IP phone 300, which instructs the IP phone 300 to decrement the amount of electronic money stored in the IP phone 300 by the service charge added in the billing section 420.

If the IP phone 300 requests the filling of the amount of electronic money from the call control section 410 (payRegist. req), the gatekeeper 400 communicates with a billing service system of a bank through a private line VAN to inform the billing service system of the request of the filling of the amount and inform the IP phone 300 of its result value (the amount to be filled) (payRegist. res). At this time, the IP Phone 300 adds the amount to be filled of the result value to the last amount of electronic money to sufficiently fill the bill process 170 used as an electronic purse. If the bank rejects the request of the filling of the amount,

the IP 300 phone takes no action.

Fig. 12a is shows a packet tunneling message format used in the present invention, which allows an existing call controlling function and a communication protocol associated with a demand of payment of a user's service charge to be performed simultaneously between the IP phone 300 and the gatekeeper 400, and Fig. 12b is a table illustrating a code division of a packet used in Fig. 12a.

Before the IP phone 300 transmits a message associated with a service charge to the gatekeeper 400, the process producing a message to be transmitted is called a packet tunneling for convenience of explanation. Such a packet tunneling 7 performs an addition of an actual service charge information (for example, codes C000, C001, C002 indicating service charge reference information) to a header portion of a nonstandard message packet (message format) 500 (a message associated with a call service is called a standard one, and a message associated with user information or a service charge, but not associated with the call service is called a nonstandard one) of messages transmitted and received between the internet (IP) phone 300 and the gatekeeper 400, and an addition of the header portion 510 to the data portion 520 upon the transmission of the nonstandard message from the IP phone terminal to the billing section 420.

Also, the transmission of a message (from the IP phone 300 to the gatekeeper 400) employs a nonstandard message transmission scheme of a protocol H. 323. For example, as shown in Fig. 12b, codes (B000, B001, B002) use a message (RAS NonStandard), and codes (B001, C000, C001, C002, R000, R001) use a message (Call NonStandard). A more concrete example can be implemented like other code messages, but is not limited to these.

Fig. 13 is a schematic diagram illustrating a state of packet analysis for implementing the present invention.

More specifically, the packet analysis state diagram constitutes the IP phone 300 of the present invention, and is performed by an EEPROM 301 having a program associated with a payment of a service charge of the present invention internally included therein. A program (Packet Analysis Machine) for performing the function of the EEPROM 301 is in an initial state (Idle) in which a call service related event (for example, the results of calculated service charges and the request for the filling of the amount) incoming from the control section (Phone process) 23 is processed. Next, when a message (Packet Analysis. req) from the control section 23 reaches the EEPROM 301 (Arrival), the EEPROM 301 requests a program portion (Packet Tunneling, Card Reader) for processing the message for each format to process the message (Analysis), starts a timer (T1), produces its result (Produce), waits for an arrival of the result from each event processor (Packet Tunneling, Card Reader) (Wait). If the result does not reach the EEPROM 301 after the lapse of the time set in the timer (Time Out), the EEPROM 301 informs the control section 23 of the time out (Report) and the state of the EEPROM 301 is converted to another idle state.

If the result from the event processor reaches the EEPROM 301 (Response), the EEPROM 301 sends the result to the phone processor (Send Report) and the state thereof is converted to the idle state.

Fig. 14 is a block diagram illustrating a flow of packet analysis for implementing the present invention, which shows an entire flow of the operation of the internet (IP) phone.

Referring to Fig. 14, when a service charge

related information message is transmitted to the IP phone 300 from the gatekeeper 400, an internet phone program allows the control section 23 to send a request message to the EEPROM 301 to analyze the arrived service charge related information message (@).

Subsequently, when the analyzed result message is transmitted to the control section 23 through a program (packet analysis process) installed in the EEPROM 301 (06), the control section 23 transmits a packet to the gatekeeper 400 or performs an internet phone call service function, if necessary.

If there is a need for a service charge related packet to be generated, the program (packet-analysis process) executed in the EEPROM 301 requests another program (Packettunnelingprocess) installed in the EEPROM 301 to generate the packet 500 to be sent to the gatekeeper 400 (02).

Accordingly, when the packet to be sent to the gatekeeper 400 reaches the program (packet-analysis process) from the program (Packet tunneling process) ( ), the program (packet-analysis process) transmits the packet to a program (phone process) to send it to the gatekeeper 400.

When a response to the request of the filling of the amount of electronic money or standard service charge-per-second information is transmitted to EEPROM 301 from the gatekeeper 400, the program (packet-analysis-process) of the EEPROM 301 transmits the response or standard service charge-per-second information to a program (Card reader process) (executed by an input/output bill processor acting as a typical electronic purse manufactured by Mondex Co.) (40), and receives a signal (Acknowledge) from the program (Card reader process) (5).

Fig. 15 is a flow chart illustrating the process routine for analyzing and producing a packet according to the present invention.

A program allowing a phone charge for a call service to be paid to the gatekeeper 400 is installed in an EEPROM 301 of the internet (IP) phone 300. At step S10, the program stored in the EEPROM 301 analyzes whether a command message of the control section 23 is a call service or a phone service charge for the call service. At steps S20, S30 and S40, if the command message is the service charge, the program iXn the EEPROM 301 allows the gatekeeper 400 to produce a service charge related message.

The steps S20, S30 and S40 further includes the steps of: requesting the processing of the message according to the type of the command message analyzed in the step S10, setting a timer, and waiting for an arrival of the result of the processed message (S20); resetting the timer when there occurs an arrival of the processed result of the requested message, and processing the result of the arrived message (S30); and releasing a request of a packet analysis and waiting for a request of another packet analysis (S40).

The step S20 further includes the steps of: informing a phone process of an arrival of non-service charge information from the gatekeeper 400 (S21) ; requesting a packet tunneling process to allow the gatekeeper 400 to produce a service charge related message (S22) ; and informing a card reader of standard service charge-per-second information and a response result to the request of the filling of the amount received from the gatekeeper 400, and waiting for the processing the informed result (S23).

The step S30 further includes the steps of: resetting the timer when there occurs an arrival of a

requested result of production of a new packet, and requesting the phone process to transmit the packet (S31) ; and allowing the card reader to receive the standard service charge-per-second information and the response result to the request of the filling of the amount from the gatekeeper 400 to send them to the bill processor 170, and then allowing informing the control section 23 of an message of the sent result (S32).

Fig. 16 is a schematic block diagram illustrating the entire construction of a communication network system for implementing a billing system according to the present invention.

Referring to Fig. 16, the internet (IP) phone 300 is allocated an internet phone number and an IP address from a server 440 through a gatekeeper 400, and stores them therein. Also, the server 440 is connected to a bank 1 through a private line to allow the gatekeeper to, in real time, collect a subscriber's service charge from the internet (IP) phone. In this case, the internet (IP) phone 300 includes an EEPROM 301 having a program allowing the service charge to be paid to the gatekeeper installed therein, and a bill processor 170 for paying a service charge to the server 440 on each call service after withdrawing and storing an amount of electronic money from a bank account. In order to pay the service charge to the server 440, the amount stored in the bill processor 170 must first be withdrawn by a usage service charge to transfer it to the gatekeeper 400, which in turn provides it to the server 440. Then, the server 400 demands a payment of the service charge from the bank 1 based on this.

Industrial Applicability As can be seen from the foregoing, according to the present invention provides, an internet (IP) phone

is equipped with a bill processor acting as an electronic purse in such a fashion that the bill processor communicates with a control section of the internet (IP) phone through an interface, so a real time-calling charge calculation is possible. In addition, a service charge related communication between the internet (IP) phone and the billing section of the gatekeeper are integrated with a signal processing for a call connection between the internet phones, so that the delay of a signal for a call connection due to a bill signal is prevented. Furthermore, a billing system is integrated with the gatekeeper so that the gatekeeper provides precise data (CDR) for a call connection between the internet phones, thereby guaranteeing a reliability of a user's service charge (a call service time).

While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiment and the drawings, but, on the contrary, it is intended to cover various modifications and variations within the spirit and scope of the appended claims.