(12) United States Patent
`Nadeau
`
`111111
`
`1111111111111111111111111111111111111111111111111111111111111
`US006240449Bl
`US 6,240,449 Bl
`May 29,2001
`
`(10) Patent No.:
`(45) Date of Patent:
`
`(54) METHOD AND APPARATUS FOR
`AUTOMATIC CALL SETUP IN DIFFERENT
`NETWORK DOMAINS
`
`Primary Examiner-Kenneth R. Coulter
`
`(57)
`
`ABSTRACT
`
`(75)
`
`Inventor: Raymond Nadeau, Verdum (CA)
`
`(73) Assignee: Norte) Networks Limited, Montreal
`(CA)
`
`( *) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`(21) Appl. No.: 09/184,030
`Nov. 2, 1998
`
`(22) Filed:
`
`Int. CI? ...................................................... G06F 13/14
`(51)
`(52) U.S. Cl. ............................................. 709/223; 709/227
`(58) Field of Search ...................................... 709/227, 223
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`6,052,680 * 4/2000 Towell
`................................... 706/47
`6,122,276 * 9/2000 Boe et a!.
`............................ 370/389
`FOREIGN PATENT DOCUMENTS
`
`WO 96 38018
`WO 9848542
`
`11/1996 (WO) .
`10/1998 (WO) .
`
`01HER PUBLICATIONS
`
`U.S. application Ser. No. 08/994,008, Charles J. Meubus et
`al., filed Dec. 18, 1997.
`IETF Internet Draft, Patrik Falstrom & Bjorn Larsson, Jun.
`1998
`ftp://ftp.ietf.org/internet-drafts/
`draft -falstrom-e 164--00. txt.
`* cited by examiner
`
`The present invention provides a method and a system for
`managing communication sessions originating in either one
`of a telecommunications network, such as the PSTN net(cid:173)
`work or a mobile telephone network, and a data communi(cid:173)
`cations network such as the Internet. The system includes a
`service logic controller supporting a data structure that holds
`a plurality of communication session disposition program
`records. The service logic controller connects with the
`telecommunications network and with the data communica(cid:173)
`tions network through respective gateways that transmit
`communication session disposition inquiry messages. In
`response to those messages, the service logic controller
`retrieves the appropriate communication session disposition
`program. If the program is instructive to establish an Internet
`domain connection, the service logic controller transmits to
`a gatekeeper functional element an Internet address request.
`The service logic controller then generates an instruction to
`the entity that originated the inquiry message in accordance
`with a response from the gatekeeper functional element. If
`the program does not require an Internet connection, the
`service logic controller generates an instruction to the entity
`that originated the inquiry message in accordance with the
`program itself. The communication session is then pro(cid:173)
`cessed according to the instruction.
`
`17 Claims, 4 Drawing Sheets
`
`Volceand/orData
`Data only
`
`AT&T, Exh. 1005, p. 1
`
`

`

`U.S. Patent
`
`May 29,2001
`
`Sheet 1 of 4
`
`US 6,240,449 Bl
`
`100
`
`102
`
`106
`PSTNACS
`Detection Point
`
`108
`PSTN ACS
`Gateway
`
`114
`Internet ACS
`Detection Point
`
`116
`Internet ACS
`Gateway
`
`118
`
`124
`IP-PSTN Gateway
`
`110
`PSTN/MN
`Delivery Point
`
`Internet
`Delivery Point
`
`Voice and/or Data
`------------ Data only
`
`Figure 1
`
`AT&T, Exh. 1005, p. 2
`
`

`

`U.S. Patent
`
`May 29,2001
`
`Sheet 2 of 4
`
`US 6,240,449 Bl
`
`122
`
`200
`CPU
`
`202
`Memory
`
`-+
`
`118
`
`206
`CPU
`I
`208
`Memory
`
`.4
`
`~
`
`~ ~
`
`~ ,
`
`210
`
`Microsoft
`ILS
`
`212
`~ H.323
`Gatekeeper
`
`Figure 2
`
`AT&T, Exh. 1005, p. 3
`
`

`

`U.S. Patent
`
`May 29,2001
`
`Sheet 3 of 4
`
`US 6,240,449 Bl
`
`100
`
`102
`
`106
`PSTN ACS
`Detection Point
`
`108
`PSTN ACS
`Gateway
`
`114
`Internet ACS
`Detection Point
`
`116
`Internet ACS
`Gateway
`
`J118l
`
`10·---~
`
`300
`Intelligent
`Peripheral
`
`124
`IP-PSTN Gateway
`
`110
`PSTN/MN
`Delivery Point
`
`120
`Internet
`Delivery Point
`
`Voice and/or Data
`------------ Data only
`
`Figure 3
`
`AT&T, Exh. 1005, p. 4
`
`

`

`U.S. Patent
`
`May 29,2001
`
`Sheet 4 of 4
`
`US 6,240,449 Bl
`
`100
`
`102
`
`106
`PSTN ACS
`Detection Point
`
`108
`PSTN ACS
`Gateway
`
`Detection Point
`
`116
`Internet ACS
`Gateway
`
`J118l
`
`7----~
`
`124
`IP-PSTN Gateway
`
`110
`PSTN/MN
`Delivery Point
`
`Internet
`Delivery Point
`
`Voice and/or Data
`------------ Data only
`
`Figure 4
`
`AT&T, Exh. 1005, p. 5
`
`

`

`US 6,240,449 Bl
`
`1
`METHOD AND APPARATUS FOR
`AUTOMATIC CALL SETUP IN DIFFERENT
`NETWORK DOMAINS
`
`FIELD OF THE INVENTION
`
`The present invention relates to the field of telephony
`systems. It is particularly applicable to such systems which
`provide subscribers with communication sessions across a
`variety of network domains, such as the Public Switched
`Telephone Network (PSTN), the Mobile network and the 10
`Internet.
`
`2
`calling, the caller will most likely end up listening to a busy
`signal, or may be connected to the called party's voice
`mailbox. If the call is completed anyhow, the caller might
`end up paying unnecessary toll charges for the last leg of the
`5 call if the called party does not live in an area deserved by
`the VOIP gateway. In all cases, the caller must explicitly
`know some extra information (IP address, VOIP gateway
`director number), and must perform some extra steps in
`order to place the call.
`Some companies offer a service based on proprietary
`devices to simplify the establishing of a call between two
`parties over the Internet. An example of such a service is the
`Internet appliance commercialized by Aplio in the United(cid:173)
`States. More information may be found on this topic at the
`15 Internet address (www.aplio.com). Unfortunately, the dis(cid:173)
`advantages of such a service are that both ends must own a
`special device, both ends must have a subscription to an
`Internet Service Provider (ISP), and the communication
`session setup requires an extended period of time.
`In summary, when a caller wishes to establish a call
`within the Internet domain, the caller must find the IP
`address of the called party through the means of different
`services available within the Internet domain. In other
`words, work and effort is required on the part of the caller;
`it is not automatic. Even if the caller wanted to complete a
`call from the Internet domain into the PSTN domain, a
`PSTN/IP gateway is required. The caller must therefore
`determine the address of such a server in the vicinity of the
`called party in order to avoid toll charges.
`Thus, there exists a need in the industry to simplify and
`refine the process of using the Internet domain, in tandem
`with both the PSTN and Mobile network, for calling pur(cid:173)
`poses within modern telephony systems.
`
`BACKGROUND OF THE INVENTION
`
`The telecommunications environment is one of continu(cid:173)
`ous evolution and technological advancement. Whereas his(cid:173)
`torically it consisted strictly of analog POTS (Plain Old
`Telephone Service), supported by the PSTN, this environ(cid:173)
`ment has expanded to include not only the Mobile network
`but also, more recently, digital data transmission of increas- 20
`ing quantity and speed, supported by the Internet.
`Prior to the introduction of the Internet, a class of tele(cid:173)
`phony services usually known as Single Number Service
`(SNS) or Personal Number Service (PNS) had been intro(cid:173)
`duced in the marketplace to address the mobility and call 25
`management needs of telephony network subscribers. The
`main characteristic of this class of services was, and still is,
`to provide call routing based on customer-programmed
`schedules, usually implemented through proprietary service
`logic, residing on either Service Control Points (SCP), an 30
`Advanced Intelligent Network (AIN) or Intelligent Network
`(IN), or on special purpose switch adjuncts or service nodes.
`The Internet has had an important effect on these telephony
`services, increasing not only the number of events and
`conditions influencing call completion decisions, but also 35
`the number of mechanisms available to reach a called party,
`as well as the number of potential call delivery points.
`Correspondingly, a co-pending patent application entitled
`"System and method for communication session disposition
`responsive to events in a telecommunications network and 40
`the Internet", filed on Dec. 18, 1997, Ser. No. 05/994,008
`and assigned to Northern Telecom Limited, now allowed
`discloses a communication session disposition mechanism
`able to make decisions regarding communication session
`disposition based on a broader range of events. The subject 45
`invention includes primarily a novel Service Logic Control-
`ler (SLC) responsive to events occurring in a telecommu(cid:173)
`nications network (PSTN or Mobile network) or a data
`communications network (such as the Internet) for making
`decisions regarding the disposition of different communica- 50
`tion sessions, for instance a telephone call or a fax trans(cid:173)
`mission.
`However, until such a flexible communication session
`disposition mechanism becomes ubiquitous in the telephony
`system, placing a call on the Internet telephony network will 55
`require a lot more from the caller than placing a call on the
`PSTN. The caller must first be connected to the Internet in
`order to figure out the address of the person to be called, and
`must also know where to look for this address. Another
`option available today is to use the services of Internet 60
`Telephony Service Providers (ITSP). In such a case, the
`caller must call into a voice-over-IP (VOIP) gateway, where
`IP stands for Internet Protocol, and supply the called party
`directory number. The gateway then routes the call through
`the Internet to the gateway closest to the called party and 65
`completes the call over the PSTN. If the called party
`happens to be connected to the Internet at the moment of
`
`OBJECTS AND STATEMENT OF THE
`INVENTION
`
`An object of the invention is to provide a novel Service
`Logic Controller (SLC) responsive to events occurring in a
`telecommunications network and a data communications
`network to make decisions regarding the disposition of a
`certain communication session, such as a telephone call or
`a fax transmission.
`Yet another object of the invention is to provide a novel
`method for using the Internet facilities to manage a com(cid:173)
`munication session originating in either one of a telecom(cid:173)
`munications network and a data communications network,
`such as the Internet.
`As embodied and broadly described herein, the invention
`provides a service logic controller for the management of
`communication sessions originating in either one of a tele(cid:173)
`communications network and the Internet, said service logic
`controller including:
`a central processing unit;
`a memory in data communicative relationship with said
`central processing unit, said memory holding a data
`structure including a plurality of records, each record
`including an information element indicative of a certain
`communication session disposition program;
`a program element in said memory that is executed by
`said central processing unit;
`a first connection point permitting to exchange data
`between said service logic controller and the telecom(cid:173)
`munications network;
`a second connection point permitting to exchange data
`with the Internet;
`
`AT&T, Exh. 1005, p. 6
`
`

`

`US 6,240,449 Bl
`
`3
`a third connection point permitting to exchange data with
`an Internet gatekeeper functional element, the Internet
`gatekeeper functional element returning in response to
`Internet address request messages Internet location
`messages;
`said program element implementing the functions of:
`a) processing a communication session disposition
`inquiry message input through either one of said first
`and second connection points to associate a certain
`record in said data structure with the communication
`session disposition inquiry message;
`b) if the communication session disposition program of
`said certain record is instructive to establish an
`Internet domain connection, generating and output(cid:173)
`ting through said third connection point an Internet
`address request message to seek an IP address of a
`party with whom a communication session is to be
`established;
`c) processing an Internet location message received at
`said third connection point in response to the Internet
`address request message and containing an IP
`address of a party with whom a communication
`session is to be established to generate and output
`through either one of said first and second connec(cid:173)
`tion points a communication session disposition
`instructions message including the IP address of a
`party with whom a communication session is to be
`established.
`Throughout this specification, the expression "communi(cid:173)
`cation session" is intended to encompass telephone-related
`messages, video-conferencing, facsimile transmissions and
`pager-related calls.
`Throughout this specification, the expression "telecom(cid:173)
`munications network" is intended to encompass networks
`through which are exchanged primarily, but not exclusively,
`audio signals, such as the Public Switched Telephone Net(cid:173)
`work (PSTN) and mobile telephone networks.
`Throughout this specification, the expression "data com(cid:173)
`munications network" refers to networks that exchange
`primarily, but not exclusively, data such as electronic mail
`and file transfers, among others. A typical example of a data
`communications network is the Internet Protocol (IP) net(cid:173)
`work.
`In a specific embodiment of this invention, the SLC
`connects with three independent network domains, namely
`the PSTN, a mobile telephone network and the Internet. The
`connection to the respective network is effected through
`gateways. Each network is provided with a Detection Point
`Functional Element (DPFE) whose task is to detect a com(cid:173)
`munication session that needs the services of the SLC. Once
`such a communication session is detected, say a caller
`originates a telephone call from the PSTN, the DPFE issues
`a communication session disposition inquiry message
`through the associated gateway, directed to the Service
`Logic Controller (SLC).
`The SLC is implemented on a server and includes a
`memory for storage of program elements implementing
`different functions necessary to the disposition of commu(cid:173)
`nication sessions and, more particularly, to the ACS service.
`The SLC server further includes a Central Processing Unit 60
`(CPU) to execute these program elements, as well as a mass
`storage unit to hold a data structure in the form of a database,
`referred to as the Subscriber Database, including a plurality
`of records, each record being a subscriber or user profile that
`contains a communication session disposition program. This 65
`communication session disposition program determines how
`a communication session to a particular called party is to be
`
`4
`managed in dependence upon various factors, such as the
`time of day, type of communication, etc. In a very specific
`example, an illustrative script can be: "Between 8 and 6 on
`working days, route calls made to John Smith to his office
`5 unless his cellular phone is activated, in which case calls
`should be routed to the cellular phone." In a specific
`example, the SLC is coupled to a Gatekeeper Functional
`Element (GKFE) to provide the SLC with means for trans(cid:173)
`parently using the Internet facilities to generate a commu-
`10 nication session disposition instruction of the Automatic
`Call Setup (ACS) service provided by the SLC. The GKFE
`is an element in the IP network where the mapping of
`pseudo-addresses into IP addresses takes place. Specifically,
`in H.323 compliant networks, the GKFE functionality is
`15 implemented on a gatekeeper which is responsible for
`managing all IP telephony related activities in a particular
`zone, performing call control, managing bandwidth and
`performing address translation. There are as many gatekeep(cid:173)
`ers as there are zones. Another implementation of a GKFE
`20 is the Microsoft Internet Locator Service which performs
`address translation. The GKFE is thus a distributed func(cid:173)
`tional element in the network. However, until the IP tele(cid:173)
`phony network is fully standardized, it is simpler to imple(cid:173)
`ment the GKFE as a single node communicating with the
`25 different gatekeepers and locator services in the Internet
`domain. This single GKFE node handles the different pro(cid:173)
`tocols needed to interact with H.323 gatekeepers and dif(cid:173)
`ferent proprietary locator services. When an Internet domain
`connection is required to complete a call, and the necessary
`30 IP address is not available in the Subscriber Database of the
`SLC, the SLC generates and transmits to the GKFE an
`Internet address request message including the pseudo(cid:173)
`address of the called party, where this pseudo-address is
`frequently an e-mail address. Upon reception of an Internet
`35 address request message from the SLC, the GKFE fetches
`the corresponding IP address from the appropriate H.323
`gatekeeper or locator service in the network. If the gate(cid:173)
`keeper or locator service is unknown, the GKFE broadcasts
`the Internet address request message, including the pseudo-
`40 address, to all known gatekeepers and locator services. This
`functionality enables the ACS service to automatically and
`transparently retrieve IP address from the IP network. The
`term "transparently" implies that an ACS subscriber is able
`to reach someone on the Internet with no permanent address
`45 without actually accessing the Internet.
`Once the communication session disposition instruction is
`generated by the SLC, a message is assembled and trans(cid:173)
`mitted to the DPFE that requested the instruction. The latter,
`upon receipt of the instruction, manages the session accord-
`50 ingly.
`As embodied and broadly described herein, the invention
`also provides a system for the management of communica(cid:173)
`tion sessions originating in either one of a telecommunica(cid:173)
`tions network and the Internet, said system comprising:
`a service logic controller, including:
`a) a central processing unit;
`b) a memory in data communicative relationship with
`said central processing unit, said memory holding a
`data structure including a plurality of records, each
`record including an information element indicative
`of a certain communication session disposition pro-
`gram;
`c) a program element in said memory that is executed
`by said central processing unit;
`d) a first connection point permitting to exchange data
`between said service logic controller and the tele(cid:173)
`communications network;
`
`55
`
`AT&T, Exh. 1005, p. 7
`
`

`

`US 6,240,449 Bl
`
`10
`
`5
`e) a second connection point permitting to exchange
`data with the Internet;
`a gatekeeper functional element in a data communicative
`relationship with said service logic controller, said
`program element implementing the functions of:
`i) processing a communication session disposition
`inquiry message input through either one of said first
`and second connection points to associate a certain
`record in said data structure with the communication
`session disposition inquiry message;
`ii) if the communication session disposition program of
`said certain record is instructive to establish an
`Internet domain connection, generating and forward(cid:173)
`ing to said gatekeeper functional element an Internet
`address request message to seek an IP address of a 15
`party with whom a communication session is to be
`established;
`said gatekeeper functional element being responsive to
`the Internet address request message to obtain the IP
`address of the party with whom a communication
`session is to be established and to generate and forward
`to said service logic controller an Internet location
`message containing the IP address of the party with
`whom a communication session is to be established,
`said program element implementing further functions,
`including:
`processing the Internet location message received at
`said third connection point to generate and output
`through either one of said first and second connec(cid:173)
`tion points a communication session disposition
`instructions message including the IP address of a
`party with whom a communication session is to be
`established.
`As embodied and broadly described herein, the invention
`also provides a method for managing a communication
`session originating in either one of a telecommunications
`network and the Internet domain, said method comprising
`the steps of:
`detecting origination of a communication session in either
`one of the telecommunications network and the Internet 40
`domain;
`suspending processing of the communication session;
`accessing a data structure containing a plurality of
`records, each record including an information element
`indicative of a certain communication session disposi(cid:173)
`tion program;
`associating a record in said data structure with the com(cid:173)
`munication session, the record including an entry
`indicative of a particular disposition program appli(cid:173)
`cable to the communication session, the entry including
`a data element indicative of a pseudo-address in the
`Internet domain;
`if the entry applicable to the communication session is
`instructive to establish an Internet domain connection,
`translating the pseudo-address to an IP address;
`utilising the IP address to manage the communication
`sesswn.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`These and other features of the present invention will
`become apparent from the following detailed description
`considered in connection with the accompanying drawings.
`It is to be understood, however, that the drawings are
`provided for purposes of illustration only and not as a
`definition of the boundaries of the invention, for which
`reference should be made to the appending claims.
`
`6
`FIG. 1 is a block diagram of a multi-domain communi(cid:173)
`cation session disposition system incorporating an Auto(cid:173)
`matic Call Setup service, in accordance with this invention;
`FIG. 2 is a structural block diagram of the ACS Service
`5 Logic Controller and IP Gatekeeper, as shown in FIG. 1;
`FIG. 3 depicts an example of a functional information
`flow, originating in the Internet domain, for the communi(cid:173)
`cation session disposition system shown in FIG. 1;
`FIG. 4 depicts an example of a functional information
`flow, originating in the PSTN/Mobile domain, for the com(cid:173)
`munication session disposition system shown in FIG. 1.
`
`DESCRIPTION OF A PREFERRED
`EMBODIMENT
`
`In a preferred embodiment of this invention, an Automatic
`Call Setup (ACS) service is provided that permits an
`improved usage of the Internet domain for calling purposes.
`Specifically, the ACS service allows the establishment of a
`20 connection from a caller (subscriber) to a called party,
`transparently using whichever network (PSTN/Mobile, IP)
`is best, based on conditions specified by the service sub(cid:173)
`scriber and external conditions. Examples of such external
`conditions are:
`25 Availability of an IP address for the called party;
`Gateway availability (e.g. all local ports could be in use);
`Time of day/Day of week (avoids waiting for IP address
`fetching at times where the called party is unlikely to be
`connected to the Internet);
`30 Cost-based routing;
`Quality of Service routing (automatically avoids using Inter(cid:173)
`net for completing a call in high Internet traffic periods).
`Therefore, the preferred embodiment of the invention
`enables a person not connected to the Internet to transpar-
`35 ently use the Internet facilities to complete a call, as well as
`facilitates call completion for people calling from the Inter(cid:173)
`net domain.
`FIG. 1 provides a block diagram of the various network
`components required by the mechanism under a preferred
`embodiment of the present invention. The various network
`components and functions shown in FIG. 1 illustrate prima-
`rily the logical relationship between these components and
`functions, and as such may have no direct implications en
`either the physical paths, direct or indirect, or the signalling
`45 supports used in the different implementations of this inven(cid:173)
`tion.
`The network components are grouped in two distinct
`domains, namely the PSTN network domain 100 and the
`Internet domain 102. As the Mobile network is very similar
`50 to the PSTN network 100, it has not been shown as a distinct
`domain in FIG. 1, but rather is also represented functionally
`by domain 100. Generally speaking, these domains issue and
`receive communications that can be telephone related mes(cid:173)
`sages or data. The system shown in FIG. 1 is a communi-
`55 cation session disposition system, capable of making dispo(cid:173)
`sition decisions based on events occurring within each of the
`network domains.
`Each domain comprises several different Functional Ele(cid:173)
`ments (FEs ). An ACS subscriber will originate a call through
`60 the ACS service by using an Originating Point Functional
`Element (OPFE). There are OPFEs in all three network
`domains, namely the PSTN or Mobile network OPFE 104,
`for example a phone in the PSTN network or a handset in the
`Mobile network, and the Internet OPFE 112, for example a
`65 multimedia PC.
`A Detection Point Functional Element (DPFE) imple(cid:173)
`ments the network functionality which is responsible for
`
`AT&T, Exh. 1005, p. 8
`
`

`

`US 6,240,449 Bl
`
`7
`identifying call requests that require ACS treatment. For
`such calls, the DPFE will suspend call processing and
`originate a request for instructions to the Service Logic
`Controller (SLC) via a Gateway Functional Element
`(GWFE). Upon reception of routing instructions from the 5
`SLC through the GWFE, the DPFE will resume call pro(cid:173)
`cessing according to the received instructions and route the
`incoming call directly to a Delivery Point FE or to the
`IP/PSTN GWFE 124 if needed. There are DPFEs in all three
`network domains, namely the PSTN/Mobile network DPFE 10
`106 and the Internet DPFE 114, each responsible for han(cid:173)
`dling the call requests from their respective domains.
`The purpose of a Gateway Functional Element (GWFE) is
`to mediate the instruction requests/responses from/to the
`DPFE to/from the SLC. There are also GWFEs in all three 15
`network domains, namely the PSTN/Mobile network GWFE
`108 and the Internet GWFE 116, each responsible for
`processing the instruction requests originating in their
`respective domain.
`The Service Logic Controller (SLC) 122 forms the core of 20
`the ACS service, and does not belong to any one specific
`network domain. The primary goal of the SLC 122 is to
`provide the DPFEs with call processing instructions. In
`order to achieve this task, the SLC 122 will consult a
`particular caller's service profile, consisting in service logic 25
`as well as a list of conditions and events to be used to process
`the caller's incoming calls. The SLC 122 is the system
`component which is actually responsive to the events occur(cid:173)
`ring within the different networks, and can be implemented
`on any suitable server that connects to the different domain 30
`gateways 108 and 116. This server includes a memory for
`storage of program elements implementing different func(cid:173)
`tions necessary to the disposition of communication sessions
`and, more particularly, to the ACS service. The server
`further includes a Central Processing Unit (CPU) to execute 35
`these program elements, as well as a mass storage unit to
`hold a Subscriber Database. This Subscriber Database con(cid:173)
`tains all of the user service profiles enabling the SLC logic
`to take a decision on call disposition, and will be described
`in more detail below.
`The functionality of the Gatekeeper Functional Element
`(GKFE) 118 is implemented on many different nodes in the
`IP telephony network. In a H.323 compliant network, these
`nodes are known as gatekeepers. A gatekeeper is responsible
`for a particular zone, whereby every VOIP client wishing to 45
`receive or make calls in this zone must first register with the
`gatekeeper. Within this zone, the gatekeeper is responsible
`for performing the translation of pseudo-addresses, fre(cid:173)
`quently e-mail addresses, into IP addresses. The address
`translation request is made by sending a H.225 ARQ 50
`(Address Request) message to the gatekeeper. This ARQ
`message includes in particular the pseudo-address to be
`translated into an IP address. The pseudo-address serves as
`identification for a particular party when registering to
`Internet directory services, and allows the gatekeeper to 55
`fetch the corresponding IP address for the particular party.
`The gatekeeper answers the ARQ message with a Location
`Confirm (LCF) message containing the IP address or with a
`Location Reject (LRJ) message if no IP address can be
`returned. As an alternative to H.323 gatekeepers, services 60
`such as Microsoft Internet Locator Service (ILS) can be used
`to perform address translation. The GKFE 118 can be
`implemented as a single node on a suitable server that
`communicates with the SLC 122 and the different H.323
`gatekeepers and other proprietary locator systems in the IP 65
`network. Similar to the SLC, the GKFE 118 server includes
`a memory for storage of the program element implementing
`
`8
`the query function necessary to the translation of a pseudo(cid:173)
`address to an IP address, where this query function involves
`the establishment of communication channels with H.323
`gatekeepers as well as with different proprietary locator
`systems. The server further includes a Central Processing
`Unit (CPU) to execute this program element.
`FIG. 2 is a structural block diagram which takes a closer
`look at both the SLC 122 and the GKFE 118. As described
`above, the SLC 122 includes a CPU 200, a memory 202 and
`a mass storage unit for the Subscriber Database 204.
`Alternatively, the Subscriber Database 204 may be included
`within the memory 202. The GKFE 118 includes a CPU 206
`and a memory 208, where the SLC 122 and the GKFE 118
`are interconnected and can exchange communication mes(cid:173)
`sages over path 214. The GKFE 118 is shown interconnected
`to two other components 210 and 212, respectively repre(cid:173)
`senting Microsoft ILS and a H.323 gatekeeper. The GKFE
`118 may establish several such connections, to other pro-
`prietary locator services and other H.323 gatekeepers. When
`the SLC 122 sends an ARQ message over path 214 to the
`GKFE 118, the GKFE 118 will extract from the ARQ
`message the pseudo-address to be mapped into an IP
`address. Next, the GKFE 118 will itself generate a query
`message including the pseudo-address, and will send this
`query message over all connections to proprietary locator
`services and other H.323 gatekeepers, for example
`Microsoft ILS 210 and H.323 gatekeeper 212. The GKFE
`118 will then await a return message from one of these
`connections mapping a valid IP address to the pseudo(cid:173)
`address. Upon reception of such a return message, the GKFE
`118 will send to the SLC 122 an LCF message including the
`IP address to be used for disposition of the communication
`session. If no such return message is received by the GKFE
`118, a LRJ message is sent to the SLC 118 indicating that the
`owner of the queried pseudo-address is not currently logged
`on to the Internet.
`The objective of the IP/PSTN GWFE 124 is to route calls
`40 between network domains, ensuring that proper protocol
`conversion as well as media conversion is applied for
`delivery to a particular Delivery Point FE. There may be
`more than one IP/PSTN GWFE required between the call's
`originating point and the call's terminating point.
`Delivery Point FEs are the functional entities to which
`outgoing calls processed by the ACS service are routed to for
`delivery to a user or any termination point, and exist in all
`three domains. Examples of a PSTN Delivery Point FE 110
`include:
`any PSTN phone where the subscriber is registered;
`a fax;
`a modem;
`an audio/video conference;
`a messaging service;
`Voice Messaging System (VMS);
`Unified/integrated messaging system.
`concerning the Mobile network, examples of a Delivery
`Point FE 110 include:
`a handset;
`a fax;
`a modem;
`a messaging service;
`Voice Messaging Service (VMS);
`Unified/integrated messaging system;
`Short Message Service (SMS).
`
`AT&T, Exh. 1005, p. 9
`
`

`

`US 6,240,449 Bl
`
`5
`
`9
`Finally, examples of an Internet Delivery Point FE 120
`include:
`a multimedia PC with:
`a Voice-over-IP (VoiP) client;
`a Fax-over-IP client;
`an Internet appliance;
`an Internet a