CA2353582A1 - System and method for providing mobile switching and multi-party services over a packet-switched network - Google Patents

Abstract

A system and method of providing an integrated wireless packet-switched network system (100, 1202) which includes IP-based switching (207) in a gateway (250) associated therewith. A cellular network portion (102) of the integrated network system comprises a radio network controller (130) for providing radio access services to mobile stations (103). A packet-switched network portion (206) is provided for transporting cellular communication traffic. An interface provided between the gateway and radio network controller includes a first protocol translator (304) for converting Transaction Capability Application Part (TCAP) messaging into IP messaging and a second protocol translator (306) for converting Integrated Services Digital Network (ISDN) User Part (ISUP) messaging into Primary Rate Interface (PRI) messaging. In some exemplary embodiments, either or both of the translators may be integrated within the IP gateway. In a further embodiment, a flash proxy agent (203) is disposed between the gateway and a Multipoint Control Unit (1302) for facilitating multi-party conferences involving ANSI-53 or proprietary flash messaging.

Description

- ' ' WO'OOI33518 PCTISE99l02163 SYSTEM AND METHOD FOR PROVIDING
MOBILE SWITCHING AND MULTI-PAR~'Y SERVICES OVER A
PACKET-SWITCHED NETWORK
PRIORITY STATEMENT UNDER 35 U.S.C ~11!9{e) & 37 C.F.R. ~1.78 This nonprovisional application claims priorit,~r based upon the following prior U.S. provisional patent application entitled: "Syste;m and Method for Providing Mobile Stations in a Radio Telecommunications Network with Multimedia Services over Packet-Based Networks," Ser. No. 60/110,811 (Attorney Docket Number 1000-0136), filed December 3, 1998, in the names of Hung Tran, Kim Vo, Bartosz Balazinski, Jean-Francois Bertrand, Laura Hernande::, and Suhail Hasan.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application discloses subj ect matter related to the subject matter disclosed in the following co-assigned patent applications: (1) "System and Method for Providing Wireless Telephony over a Packet-Switched Network," filed October 26, 1999, Ser. No. (Attorney Docket Number 1000-144), in the names of Kim Vo, George Foti, Hung Tran, Jean-Francois Bertrand, Bartosz Balazinski, Francis Lupien, Zeng-Jun Xiang, and Yang Lu; (2) "System and Method for Mobile Terminal Registration in an Integrated Wireless Packet-Switched Network," filed October 26, 1999, Ser. No. (Attorney Docket Number 1000-154), in the names of Hung Tran, Laura Hernandez, Jean-Francois Bertrand, and Bartosz Balazinski.
BACKGROUND OF THE INVENTION
Technical Field of the Invention The present invention relates to telecommunication systems and, more particularly, to a system and method for providing mobile switching and mufti-party services over a packet-switched network such as, for example, a network using the Internet Protocol (IP). ' VYU Uul.la710 r . , , _ _2-I~escn~ of Related Art Coupled with the phenomenal growth in p~opulari'y of the Internet, there has been a tremendous interest in using packet-switched network infi'astructutes (e-g., chose based on IP addressing) ass a replacement for the existing circuit-switched network infrastructures used in today's telephony. From the fretwork operators' perspective, the inherent uaffic aggregation in paclket-switched infrasuuctures allows for a reduction in the cast of transmission and the infrastructure cost per end-user.
Ultimately, such cast reductions enable the network operators to pass on the concomitant cost savings to the end-users.
~e existing Voice-over-IP (VoIP) net'vorks implement communications infrastructures chat are typically based on mui'tiple protocols which include, for example, the well-knowan H.323 protocol. These: protocols are primarily ot7ented to operating with fixed-neT~'ork-based telecommunications protocols and arc designed to provide such services as call control, et cexer'~~, for wireline subscribers. Cutient VoIP systems, accordingly, cannot be used advarvtageou.sly in wireless environrnenis, although some VoIP systems may support rudimentary location managem~t services.
There exist several inadequacies in the Plain CJId Cellular System (POCS) with respect to supposing 1P-based infrastructures and seraices. Also, there exist deficiencies and shortcomings in the existing 1P-based VoIP systems in Germs of 24 supportingwireless access technology such as for example, ANSI-136, Global System for Mobile communications (GSIVI],1S-95, et cetera. Some pf the more slgtuftcant of these inadequacies and shortcomings ate sumrnati2ed below.
First, cunentPOCS systems and technology infrastructures are not compatible with communications infrastructures as reqr.iired by the Vole standards. The 25 operation, maintenance, and the connection management required by the tra~~ional ppCS systems ate based on switched physical hunk copnections. These mechanisms ue noG compatible with the packet switch's glrouttng mechanisms such as, e-g., Domain Name System (DNS), Dynamic Host Configuration Protocol (DHCP), etc.
required far managing devicclh4st addressing and configiuation.
3Q InGatnpatibilities also exist between '.POCS protocols atad communications protocols of the existing vow applications. 'The POCS sY~et~ cannot support a Plain d- ' WO '00/33518 PCT/SE99/02163 Old Telephone System (POTS) or Integrated Services Digital Network (ISDN) client in the Internet context. The Internet "client" is typiically required to handle Internet-based protocols such as, e.g., Real-time Transfer Protocol (RTP), Resource Reservation Protocol (RSVP), etc. which are not in the definition or domain of the POCS systems.
Another important disparity which should b~e noted is that the POCS signaling and user data planes use distinct physical transport and network facilities, whereas the same physical network facilities are used to route signaling and user data information in the Internet domain.
With respect to the inadequacies of the existing VoIP systems, it should be appreciated that current VoIP clients and infrastructiare can handle neither the wireless access-side technology nor the basic network-side functional signaling plane which enables mobility management, authentication/security, service definition, service mitigation and execution, et cetera. Clearly, the provision of such advancements in the POCS as Wireless Intelligent Network (WIN) services, can onlymagnify these and other disparities and incompatibilities between the POCS and VoIP
infrastructures.
Based on the foregoing, it is apparent that i:n order to address these and other problems of the current technologies set forth above, what is needed is a seamless integration between the existing POCS and VoIP infrastructures so that the numerous advantages, known and hitherto unknown, of packet-based networks may be realized within the context of wireless telecommunication;>. However, as those of ordinary skill in the art should readily appreciate, critical to implementing mobile network infrastructures within a VoIP system is providing end-user switching services on an iP-based core network in an economical way.
In addition, it should be further appreciated that in an integrated network that supports both mobile stations and lP terminals, it would be very advantageous if the IP entity that facilitates mufti-party services such as, e.g., a three-party conference, in accordance with a current protocol, e.g., the H.323 standard, can still be used for such services regardless of the access. However, it is well-known that the current procedures for setting up a three-party corrfer~nce; using the H.323 protocol do not support call enquiry, call waiting, or three-party conferencing as defined by the mobile wcr uut~»ta _ PCTlSE99ip2163 a . ;

communicaiiotis standard ANSI-53 or certain proprietary flash messaging schemes_ Thus, it would be of significant benefit to provide a system arid method for supporting the ANSI-~3 or proprietary flash messaging within the context of art irstegtrated VoIP
system.
SUMMARY OF THE INVENTION
In one aspeet, the present invention is dir~:cted to an integrated wireless packet-switched network for providing telecommunications services to a mobile subscriber.
The network co;nprises an IP-based network portion for u'ansporCing co~tuttication 7 0 traffic relating to the mobile subscriber. A radio network controller is provided for controlling radio access for the mobile subscriber. A gateway is disposed between the packet-switched network (ll'-based) portiotn and the radio network controller.
Further, the gateway includes means for switching the c:omrnunication traffic relating to the mobile subscribez.
The interface between the gateway and radio network controller includes a first protocol translator for converting Transaction Capability Application Part (TCAF) messaging into IP messaging and a second protocol translator for convet; ring lrttegrated Services Digital Network (ISpl~ User Part (1;SUP) messaging into Primary Raze Interface (PRI) messaging. In some exemplar5r erttbodiments, either or both.
of the translators may be integrated within the IP gatemay.
In another aspect, the present invention its directed to a method of registering a mobile terminal in an integrated wireless pads:et-switched network which anclndes a cellular nehyork portion and a packet-swil~ched network portion. The cellular network portion comprises a serving radio >netlvor3c controller (RNC) for pmvzding ~5 wdio access services for the mobile terminal. 'j~e packet-switched network portion includes a gatekeeper and a gateway, wherein the gateway comprises an IP stack for switching cellular traffic related to the mobile: terminal- The method begins by determining, in the serving RNC, that the mobilu° tertrtinal is located in a service area associated with the seining ~tNC. Responsive to the determining step, azs Invoke message is sent from the serving RNC to the gateway, wherein a Registration >:,Tpdaie signal is encapsulated in ibe Invoke message. I1'pon receiving the Invoke message, a W
WO 44133518 PC7"/SE99102163 -S_ Registration Request message is then sent from the gateway to the gatekeeper, the Registration Request message including a ternainalAlias parameter. Responsive thereto, a Registration Confirm message is sent from the gatekeeper to the gateway if the mobile terminal is successfully registered at the gatekeeper.
Otherwise, a Registration Reject message is sent from the gatekeeper to the gateway.
Thereafter, responsive to receiving either the Registration Confirm message or the Registration Reject message, a registration status of the mobile terminal is reported via a Return Result message sent by the gateway to the RNC.
in a further aspect, the present invention is related to a method of de-registering a mobile terminal in an integrated wireless pacl~;et-switched network system which includes a cellular network portion and a packet-switched network portion. The cellular and packet-switched network portions include components as set forth above.
The method begins by first determining, in the serving RNC, that the mobile terminal located in a service area associated with the serving RNC has powered down.
1 S Responsive to the determining step, an Invoke message is sent from the serving RNC
to the gateway, wherein a Registration Update signal is encapsulated in the Invoke message. Upon receiving the Invoke message, a~z Unregistration Request message is sent from the gateway to the gatekeeper, the Unre~;istration Request message including an endpointAIias parameter. Responsive thereto, an Unregistration Confirm message is sent from the gatekeeper to the gateway if the mobile terminal is successfully unregistered at the gatekeeper. Otherwise, an Unregistration Reject message is sent from the gatekeeper to the gateway. Subsequent3!y, responsive to receiving one ofthe Unregistration Confirm and Unregistration Reject: messages, a registration status ofthe mobile terminal is reported via a Return Result nnessage sent from the gateway to the RNC.
In a still further aspect, the present invention is directed to an integrated wireless packet-switched network having a wireless portion and an Internet Protocol (IP) portion. The IP portion preferably includes a gateway for interfacing with the wireless portion. The network system comprises a radio network controller for providing radio access services to a mobile~ubscriber. The gateway includes means for switching communication traffic relating to 'the mobile subscriber. The network WO 00l33S18 syste:Gn further inc hides one or more protocol ttar~slators disposed between the gateway and the radio network controller.
In yet another aspect, the present invent~,on prAVides an integrated Voice over IP (VoIP) network that is capable of supporting tnulti-pat~tyse~viees involving ANSI-53 messaging or proprietary flash messaging. The V oiP network preferably comprises a radio network controller that provides radio access services to one or more mobile subscribers. A gateway is operably coupled to the radio network controller for combining a packet-swliched portion and a circuit-switched cellular portion of the integated VoIP network. A Multipoint Control Unit (MC1.>] for setting up inulii-pity IO services is wnnected to d1e packtt-switched potion. A flash proxy agent is disposed between the MCU and the gateway for ma~Pping ANSI-53 or proprietary #lash messages relating to the rr~ulti-party services into messages compatible with the MCU.
In alicmative embodiments, the flash proxy agent may be integrated within suitable H.323 components such as, e.g., the MCU or ihr gateway.
BRIEF DFSCRLPTION OF THE 1')RA,Wf.I~~IGS
A more complete understanding of Llhe present invention inay be had by reference to the following Detailed l3escription when taken in conjunction with the accompanying drawings wherein:
FIG. 1 depicts a functional block diagram, of a wireless IP (WLIF) netwot~ in accordance with the teachings of the present invention;
FiG. 2 depicts a functional block diagram of a pardon of the exemplary WLIP
network with additional components for providing 3P-based switehiug;
FIG_ 3 depicts a functional block diag~~m of an addressing scheme for use in the ViTLIP network;
FIGS. 4A acrd 4B depict, respectively, control message pathways fox ragistration and de-regisiration of a mobile station in the V~LIp network;
FIG. S depicts a control message pathway for placing a call from a mobile station in the network:
FIG. 6 depicts a control message pathway for placing a call to a mobile station in the WLIP network;

WO 00/33518 PCTlSE99l02163 a > , , - - .
FIG. 7 depicts a control message pathway for an exemplary embodiment of a call waiting scenario in the WLIP network;
FIG. 8 depicts a control message pathway for an exemplary embodiment of a call enquiry scenario in the WLIP network;
FIG. 9 depicts a control message pathway for supporting an exemplary embodiment of a mufti-party conference in the WLIP network;
FIG. 10 depicts a functional block diagram of another view of the WLTP
network portion for supporting mufti-party services using a Multipoint Control Unit (MCU);
FIG. 11 depicts a functional block diagram. of the WLD' network portion with the MCU for supporting mufti-party services using ,a flash agent provided in accordance with the teachings of the present invention;
FIGS. 12-14 depict control message pathways for additional embodiments of a mufti-party conference using the flash agent; and FIGS. 15 and 16 depict control message pathways for additional exemplary embodiments of call waiting scenarios in the WLIP network portion having the flash agent.
DETAILED DESCRIPTION OF EMBODIMIM:NTS
FIG. 1 depicts a functional block diagram ~of a WLIP network system 100 for providing H.323-based mobile switching in accordance with the teachings of the present invention. A legacy PSTNlPLMN network portion 102 is connected to a Home Location Register (HLR) 1 b0 via a Signaling System hIo. 7 (SS?) path 257. An H.323-based VoIP portion 206 comprises an IF' network 207 disposed among a plurality of H.323-compliant components such as, for example, a gatekeeper 200, one or more terminals (e.g., terminal 203), one or more PCS (e.g., PC 202), a Multipoint Conference Unit (MC'I>7 204, et cetera.
1n order to integrate the VoIP network portion 206 with the POCS
infrastructure, a conventional Mobile Switching C'.enter (MSC) of the POCS
network is modified in accordance with the teachin~s~f the present invention to provide only radio services. Accordingly, the switching functionality of the MSC is removed J r s r therefrom such than it becomes a Radio Networ;h Controller (RNC), for example, RNC
130 shown in FIG. 1. A.n IP or RhTC gateway ?S0 is provided preferably as an interface between the Ip network 207 and the ItNC 130. The IPIRNC gateway 250 is an H.3?3-compliant gateway that is suitably tttodifled to support the comrnttnication S between the H.323 network acid the RNC I3!). An SS7lANSI-41 path 2I0 is used between the RNC 130 and the IP gateway 250 during call setup. An ISI?N User Part (ISUP) signaling path 208 is also provided between the RNC 130 and the IP
gateway ?~0 in order to . establish trunk coiulectiorts fer'r voice transferring dtuing the call.
The gatekeeper (GK) 200 operates as a mobility server for keeping 'track of vatians call clients and servers. In addition, the gatekeeper 200 maintains registration and status information with respect to mobile stations (for example, MS 103) and H.323 clients in general- PrGferahly, the gatekeeper 200 is provided as an H.323 entity on the IP network 207 (which lnay comprise' a Local Area Network) that provides address tratulation alnd controls access to the network for the otherl"i.323 components.
IS The H.3?3 terminals (e.g., terminal 203) are preferably provided as 1P
clienu that may transfer voice, video, and multimedia data- The MCTJ 204 is preferably provided for establishing conference calls and rnuIti-party services. Although not specifically shown in this FIG., a Multipoirst Controller (MC) may also be provided as part of the VoIP portion 206_ Furthermore, a "plain" PSTN gateway 249 may be provided between the VoII' network portion 20b and the legacy PSTNIPLMN network portion 102 with a conneeuan 253. Alternatively, the legacy PSTNIPLMN network po~ttion 102 is coupled to the IP network 207 via the IPI~NC gateway 250. Accordingly, it should be realized that the GK 204 may decide to route a cah to the external aetwork (i.e., the PSTNIPLMN portion 102) via eithc~~ the IPIRNC GW 250 or the PSTN GW
ZS 249, using their respective paths alternatively ~(i-e., path 255 or path 253, respectively).
The G~ may also perform a load balancing or bandwidth control fvnctit~n with respect to such rousing to the external network poriit>tz.
FIG. 2 .illttsttates a functional diagtram of a relevant portion 202 of the exemplary WLIP network system 100 shown in FIG. I, with additional details provided for the gateway RNC interface pathway. A f~rsi protocol ua~rislaior (TI) 304 is preferably provided as an SS7 stack or; the path 210 fat convetvng Trausaction Capability Application Part (TCAP) messaging into suitable IP messaging. A
second protocol translator (T2) 306 is provided on the path 208 for performing the translation between ISUP messaging and Primary Rate Ir.~terface (PRI} messaging. Those of ordinary skill in the art should readily understand that either or both of the translators provided in accordance herewith may be integrated within the IP/RNC gateway in some implementations. Further, although not shown in FIG. 1 or FIG.2, cellular entities such as, for example, a Visitor Location Register {VLR), one or more base stations, an Authentication Center (AC), Service Control Points (SCPs), et cetera, may be included within the WLIP network system 100.
Referring now to FIG. 3, shown therein is a functional block diagram of an exemplary addressing scheme for use in the VVLIP network 100. Preferably, the address translation between the Location Area (LA) and the RNC is performed only when the IP gateway 250 supports more than one. RNC. An RNC, e.g., RNC 130, may control one or more base stations (BSs). For <;xample, BS 140A and BS140B are shown in this FIG. Translation between Mabile Identification Number (IVIll~
and LA
is preferably performed only when the LA information is to be maintained within an access network instead of the gatekeeper 200. The LA information may be transmitted to the gatekeeper 200 as a terminalAlias parameter in a Registration Request (RRQ) message and may be returned as a destinationlnfo or srclnfo parameter in an Admission Confirm {ACF) message. It should be appreciated that the LA
information may also be sent as nonStandardData in the RRQ and ACF messages. In a presently preferred exemplary embodiment ofthe present :invention, a mobile station (MS) may be paged globally.
Referring now to FIG. 4A, a control message pathway is illustrated therein for registering an MS (e.g., MS 103) disposed in the WLIP network 100. After determining that the MS 103 is located within its serving area, the serving sends an AhtSI-41 private message, e.g., H32'3 Invoke message 602 to the RNC
gateway 250. The MSS-MRS RegUpdate signal is encapsulated within the H323 Invoke message 602. Upon receiving the InvolcE~ message 602, the RNC gateway sends a RAS RRQ message 604 to the gatel~:eper 200.
If the MS has previously registered with a gateway within the domain of the ..r, ww.......s'r 1 ~..yJ~.aTINi/W

gatekeeper 200, the gatekeeper 200 simply returns a RAS ACF message.
Otherwise, it stores the MIN as an arias of the gateway and remirns a RAS Registration Confirm (RCF~ message 606. If the MS has failed the registration process; a R~IS
Registration Reject (RR.>) return message (also labeled as message 606) may be sent. Upon receiving either the ,RAS RCF AT RRJ message 606, the IPIR,NC gateway 250 constructs alt ANSI-41 private tnessage, H313 Return Restclt (RR) response message 616, by wrapping the MSS-MRS RegUpdateR signal and returns it to the Rh'C 134.
FIG_ 4B depicts a control message pathway for de-registering an MS (e.g_, MS
103) in the WLIP network I QO provided it1 accordance with the teachings of the present iz?vention. The RNC 130 sends an ANSI-~~ 1 H323 Invoke message 6I 0 (with encapsulated MSS-MRS RegUpdctte signal) to the IPlRNC gateway X50 to inform the )i.323 IP network 206 that the MS I03 has powe~:d down. Upon receiving the Invoke message 610, the gateway 250 sends a R.AS Unregistratton Request (URQ) I S message 61z to the gatekeeper 200 to remove. the MS fxom its registry. An ert~poirztAlias parameter is provided within thE: RAS URQ message 6I3. After determining that the registration of the MS can be revoked, the gatekeeper 200 updates its tegisttyappropriately and $etids aRAS Unreg~strarion Conf rm (L1C.F~
message 614 to the IP1RNC gateway 350. if the registration of 'the MS cannot be revoked for some reason, the gatekeeper 200 transmits aIsAS Unregisrration Reject (ZIR.n message (also denoted as message 614) to the gateway. Thereafter, responsive to the UCF or URl message 614, the iPIRNC gateway 250 reads an ANSI-41 H323 RR response message 616 to the RNC 130, including the encapsulated RegUpdøreR signal thereiTi.
Referring to FIG. 5, depicted therein is a control message pathway for placing a call from an MS to a terminal (e.g., terminal 203 shown in F1G_ 1 or FIG. 2) disposed in the WLIP network 100. An ANSI-41 H323 Invoke message 702 (with an encapsulated SetizeTCII sigaal) is sent from the RNC 130 to the 1PlRNC gateway zS 0.
Responsive thereto, a R~ISAdmission Request (Ai~~l) message 704 which includes the calling and caDed parties' nurrtbe~ (A# and B#, respectively) is sent fTOtn the 1P/RNC
gateway 250 to the gatekeeper 200. A .RAS ACS' message 706 is then returned from the gatekeeper 200.

WO 00!33518 Y t ~ y - -After receiving the ACF message 70b, the IP/RNC gateway 250 determines if the call can be handled. If not, an ANSI-4I H323 RR message 708 including suitable parametric information, e.g., CallCong parameter, is returned to the RNC 130.
Otherwise, the IP/RNC gateway 2S0 returns an ANSI-41 H323 Invoke message 7I0 S with a ConnectMS2 parameter to the RNC 130. In response thereto, an ANSI-41 RR message 712 including a MSConnected parameter is returned to the gateway 250.
Subsequently, a trunk connection 714 is established between the gateway 250 and RNC 130 using the B# and a suffix received in the MSConnected parameter.
Thereafter, a Q.931 Setup message ? 16 with appropriate parametric information is sent from the IPlRNC gateway 250 to the terminal 203. In response, a Q.931 Call Proceeding message 718 is returned from the terminal 203 to the gateway 250. The terminal 203 also engages in RAS :messaging with the gatekeeper 200 as shown by the RAS ARQ and ACF messages 72:0 and 722, respectively. After completing the RASmessaging, the terminal 203 sends a Q.931 Alertingmessage 1 S to the IP/RNC gateway 250. After a ringback tone 7.>.6 from the gateway 250 to the RNC 130, a Q.93I Connect message 728 is sent by tlhe terminal 203 to the gateway 250. Thereafter, an H.24S phase 730 is established !between the RNC 130 and the terminal 203.
Referring now to FIG. 6, illustrated therein is a control flow pathway for placing a call to an MS from a terminal or a wireline phone. A voice gateway (GW) 152 is provided as a media gateway, preferably for interfacing between the VoIP
network portion and the PSTN (not shown). Pursuant to the call to be placed to the MS, the voice GW 1S2 first engages in RAS messaging with the gatekeeper 200 as exemplified by ARQ and ACF messages 802 and $t)4, respectively. Thereafter, a Q.93I Setup message 806 with appropriate parametric information is sent from the voice GW to the IP/RNC gateway 250. Responsive thereto, the IP/RNC gateway 250 sends a Call Proceeding message 808 to the voice G~JV 1 S2.
The IP/RNC gateway 2S0 then engages in its own RAS messaging with the gatekeeper 200 as depicted by ARQ and ACF messages 8I0 and 812, respectively.
Subsequently, the IP/RNC gateway 2S0 sends an,l~NS~I-4I H323Invoke message 814 to the RNC 130 with a FindMSposl signal encapsulated therein. After successfully WO 00133518 Yi: I l~k~'IIUZIC3 finding the MS' location, the RNC 130 responds by returning an ATISI-41 H313 RR
message 816 with the encapsulated MSpasfouhdl signal- Thereafter, a trunk connection 822 is established between the RNC 130 and the IPIRNC gateway 250, pursuant to the H3.23 Invoke and RR messages 818 and 820; respectively. 'These messages include, respectively, ConnecrMS1 and MSCo~t~tected parameters.
Subsequent to additional ANSI-41 H323 Invoke and ,R.R messages (messages 8z4 and 826, which include Alert Wirtfo andAlenWInfoR pa~'ameters, respect;vely) between the RNC 130 and the IP/RNC gateway 250, a Q.931 ~llerriag message 828 is propagated from the IP/RNC gateway 2S0 to the voice GW 152.
Thereat $ddition.al ANSI-aT 3i31.31nvoke aid RR messages (messages 830 and g32, respectively) between the RNC I 30 and the IflRNC gateway 250 give rise ~o a Q_93I Connecr message 834 that is propagated from the IPlRNC gateway 250 to the voce GW 152_ An H-245 phase 730 is then es~rabtished between the ltNC 130 and voice GW I52.
1 S FIGS. 7 through 9 depict conaoi message pathways for multi-partytransactions involving prs~prietaty hash messages which are converted or mapped to appropriate H_323 messages by a flash proxy agent that is des~~ribed-in greater detail hereinbelow:
Referring now to FIG- 7, a control message pathway for a call waiting scenario involving a Private Branch Exchange (PBX) 100:2 in the WLIP network 100 is shown therein. A twa-parry call (desigltat~i as the .A-B cali) 1004 is fast estabushdl preferably in amatuter set fort3~ above. When a tturd party caller (C) atcetnpts to teach the B party, a number of Q.931 and RAS lacssag~es (messages 1006 - Z 020) similar to those described hereinahove are RroPagated mong the PBX 100?, voice GW 152, IPIRNC gateway 250 and, the gatekeeper 200. Thereafter, a CaIIWa=ring tone 2S is issued from the IPIRNC gateway 250 to the RNC 130 serving ihc MS. After a Q.931 Alening message 102 is sent from the gateway 250 to the k'BX 1002, a flushwi~fo message 1024 is sent by the RN(. 130 to the IPlRNC gateway 250.
.Responsive thereto, a hold message 1028 is issued by the IP/RNC gateway 250 to the voice GW 152 for holding The A-B call. A hold ark message is returned from the voice GW 152 thereafter. Subsequently, a Q.93'1 Conned message 1032 is sent by the 1P/,RNC gateway 250 to the PBX 1002 for effectuating the C-B call.

WOr00I33518 PCT/SE99102153 FIG. 8 depicts a control message pathway for an exemplary call enquiry scenario in the WL1P network 100 of the present invention. It should be readily appreciated that the establishment of a two-party call 1102 and subsequent control messages 1104 -1128 are similar to those described in greater detail in the foregoing sections. Accordingly, it is believed that the exemplary call enquiry method is readily apparent from FIG. 8 and the description above taken '.in conjunction herewith.
Referring now to FIG. 9, depicted therein is a control message pathway for supporting a three-party conference in the WLIP network 100. Preferably, a 3-party state 1202 is established with decentralized control, for example, in a multicast manner, of the parties involved. Aflashwinfo message '1204 is sent from the to the If /RNC gateway 250 after a two-party call (e.g., .~-B call) has been put on hold.
Responsive to the flashwinfo message 1204, the IP/RNC gateway 250 sends a retrieve message 1206 to the voice GW I52 in order to effectuate the retrieval of the held A-B
call. A retrieve ack response message 1208 is returned from the voice GW 152 to the I S IP/RNC gateway 250. It should be realized by those ~of ordinary skill in the art that the decentralized multipoint conference method of tlhe present invention may not involve apoint-to-point call setup ofthe participating terminalslclients with the MCU.
Based on the foregoing, it should be appreciated that the present invention advantageously provides an integrated wireless IP network solution for realizing end-user switching services on a packet-based network. Furthermore, the present invention provides an inexpensive way to integrate IP-based switching with cellular networks because of the ease of the provision of an IP switc;hing stack in a gateway and removing the costly MSC components from the network. Accordingly, it should be further appreciated that by using the present invention, .operators can quickly and cost-effectively provide IP-based cellular telephony solutions within compact LAN
architectures.
In the following portions of the Detailed Description, a system and method is provided for supporting mufti-party services in an intel~ated network using the MCU
wherein conventional ANSI-53 messaging is appropriately mapped to suitable H.323 procedures.

. r~ a ~atyy/UT I b3 ,1~-FIG. 10 depicts a functional block diagam of another view of the WLIP
network portion 1202 far supporting mufti-patty conferences using an MCU 1302.
Because the teachings of the present invention are exemplified using an 1:-L323-based network, a brief description of the H.3?3 entities is. provided hereinbelaw_ The H.323 standard def ties four major types of components for forn~g an inter-operable network: terminals, gateways, gaceke.epers and multipoint control units (MCLJs). In general, terminals, gateways and MCUs of an H.323-based network are referred to as "endpoints-" Gateways are typicah.y provided between networks {or network portions) that operate based on different standards or protocols. For eXample, one err mare gateways may be provided between a packet-switched network portion and a circuit~switched network portion. Terminals are employed by end-users for accessing the network or portions thereoly for example, for placing or receiving a call, or for accessing multimedia content at a remote site.
The gatekeeper is typically defined as the entity on the network that provides I S address translation and cozltrols access to tl;e netvaork for other H.323 components-Usually, a gatekeeper is provided with the address wanslation capability for a speci fled portion of the network called a "zone: ' Accordingly, a plurality of gatekeepers may be provided for carrying out address translation that is necessary for the entire network, each gatekeeper being responsible for a particular zone. In addition, gatekeepers may also pFOVide other services to ih~e terminals, gateways, and MCUs such as bandwidth management and gateway location.
The H.323 standard defines multiple types of add~tesses associated with each endpoint such as, for exaruple, a transport address (which, for example, corresponds to the IP address and the port address of a tertnin~a operated by the end-user) and an alias address. A.n endpoint may have one or more aliases associated with it.
Exemplary aliases rttay include the well known E_'k64 telephone numbers, H.323 >Ds (such as names, email-like addresse$, etc.), and so on_ 'j'he address translation service of the gatekeeper provides art alternative method of addressing an endpoint wttercin a user-friendly alias (e.g., the E.l6a telephone number) associated therewith may be translated into its appropriate transport address used by the ptotocol-Continuing to refer to FIG. 10, the exemplary VoIP core network 206 r r , , - -comprises one or more gatekeepers (e.g., gatekeepers 200A and 2008), one or more terminals (e.g., VCONI terminal 1304 and VCON:? terminal I306), et cetera, in addition to the MCU 1302. Further, the gateway .?SO is preferably provided for interfacing with a radio network controller (e.g., RNC I 30) as described hereinabove.
S One or more base stations, for example, BS 1204, amd associated MSs (e.g., 103A and MS2 1038) are preferably disposed in the cellular network portion of the WLIP network I00 as described hereinabove.
Conventionally, the MCU 1302 is provided within the H.323-based VoIP core 206 as an endpoint for providing the capability for three or more terminals and I O gateways to participate in a multipoint conference. V~Jhile the MCU 1302 is capable of supporting a conference involving the H.323 enfiities, it is well-known that the current procedures used in setting up an H.323 conference do not support mufti-party services such as call enquiry, call waiting, or 3-party conferences, as defined by the mobile communications standard ANSI-S3.
15 FIG. I I depicts a functional block diagram of yet another view of the WLIP
network portion 1203 for supporting mufti-party services using a flash agent provided in accordance with the teachings of the prcaent invention. Only relevant portions of the overall network architecture are depicted in this FIGURE. The flash agent 203 is preferably provided as a proxy device disposed between the gateway 2S0 20 and the MCU 1302. Accordingly, the flash agent 203 maps an ANSI-S3 flash, or such other proprietary flash messages as maybe appropriate (e.g., the flash messages shown in FIGS. 7 through 9) to a suitable H.323 procedure for creating a conference or effectuating a mufti-party service. FIGS. 12-14 depict control message pathways for additional exemplary embodiments of a three-party conference service in accordance 2S with the teachings of the present invention. FIGS. 1 S and 16 depict control message pathways for two additional exemplary call waiting scenarios, respectively. It should be understood that in each of these FIGURES described immediately hereinbelow the flash agent 203 is advantageously utilized between tire gateway 2S0 and MCU

for mapping ANSI-S3 messages.
30 The scenario where an H.323 terminal (egg., VCONI 1304) is the creator of a mufti-party conference is exemplified in FIG.12. Initially, the VCONI terminal rr... vv.r...m r~r~~,~,.,~~~'~
s r ~ . , creates a two-patty coufetettce with an MS by sending a Create message 1402 to the IVfCU 1302. The Create message I402 preferably includes a conference password (e.g., 8711), a separator (which may be provided as a sequence of special characters, e.g., ~''), and the MS' telephone number' (e.g_, 888-555-0001 ). Ln response, the MCU
S 1302 sends an I»vire message 1 t+04 which contains the password and telephone number information received from the VCON I temainal 1304 to the gateway 250_ .A.
Call 1406 is theft placed by the gateway 250 to the MS using this information which is routed via the RNC 130.
An ANSI-53 Flash message 1408 containing the third parry"s telephone number, for example, the telephone number 7~7-S55-OpQ2 which belongs to the YCON2 terminal 1306, is sent from the RNC 130 to the gateway 250, responsive to the data entered at the MS pursuant co a second eotaf ~rence password. When the Flash message 1408 is received at the gateway 250, the fit<~t conference passwot~d (i.e., 8711 ) is preferably stored, and the LAN connection is put on hold (i.e., the )ZTP
speech handler and a call handier associated with the initial two-patty conference are disassociated). A Create message 1412 is generated by the. gateway 250 Which includes the second conference password {e.g., 8712), a separator (which may again be provided as a sequence of special chaTactets, e.g., ss), and the telephone number for the VCONZ terminal 1306. This message 1412 is sent from. the gateway 250 to the MCU 1302.
Responsive to the Geate message 1412" the MCU 1302 sends an Invite message 14I4 to the VCON2 terminal 1306, including the password Gild telephone number information, fox connecting the tern~.inal with the MS. Thereafter; the MS
toggles between the Qrigittal MS-VCONl conueciion azld the MS-VCON2 coruleCtiop until a three-parry state is achieved. The wglling between the connections is preferably effectuated by sending Flash messages with embedded codes (e.g., messages 1418,1422, and 1426) and propagating, Release messages {e.g., messages 1~i16apd14I8)betweenihegateway25flandtheV'CONtc~tsrtinals. Afteerestabtishing the three-patty state pursuam to the Flash message I434, a Release message 1436 is propagated between the gateway 250 arid the MhU 1342. Subsequently, the tluee parties,.i.e., the MS and the two VCON terminals are engaged in. a phone confes~tce.

WO 00l33S18 PCT/SE99/02163 FIG. 13 depicts the control message pathway for the situation where the MS
is the creator of the original two-party conference with a VCON terminal. The control messages I 502 - 1536 are substantially similar to those described above in reference S to FIG. I2 and accordingly, only the salient features with respect to this exemplary call scenario are described herein. The MS creates and invites the VCONI terminal to the first conference connection via dialing a conference password (e:g., 8711), a separator, and the terminal's telephanenumber(e.g., 7'77-555-0001) (control messages 1502, 1506, and 1508). Subsequently, after sending a Flash message 1504, the MS
creates and invites the VCON2 terminal 1306 to the second conference connection via dialing another conference password (e.g., 8712), a separator, and the second terminal's telephone number (e.g., 777-555-0002) (control messages 1512-1514).
FIG. 14 depicts the conference scenario wherE; two MSs, e.g., MS1 103A and MS2 103B, are involved in the call connections. Again, only the salient features of I S this callflow are set forth. MS 1 103A is provided to be the creator of the original two-party call. MS2 103B is the creator of the enquiry two-party conference connection.
MS1 creates and invites MS2 to the first conference via dialing in the data as exemplified above. The control messages 1604-160E~ illustrate this callflow portion.
MS2 creates and invites a terminal (e.g., the VCON'2 terminal 1306) to the second conference by dialing in the requisite data as shown lby messages 1614-1616.
After a three-party state is achieved as explained in the foregoing, a Release message 1638 is propagated between the gateway 250 and MCU 1302.
FIG. I S depicts a control message pathway for an exemplary embodiment of a call waiting scenario in the WLIP network portion 12:03 provided in accordance with the teachings of the present invention. In this embodiment, MS 1 103A receives a call from the VGONI terminal 1304 while engaged in a two-party conference with MS2 103B, as shown by control messages 1702-1708. The call from the VCONl terminal 1304 is preferably effectuated in the same manner as described hereinabove.
After receiving an Invite message 1712 from the MCU 130:2, an H.323 Admission Request (ARQ) message is sent from the gateway 25Q tc~the gatekeeper (not shown in this FIG.). Upon receiving an Admission Confirm (ACF) response message therefrom, the gateway 250 stores the ID of the call handler associated with the two-patty conference and issues a Call rYaiting tone 1716 to the RNC 13~D. Depending upon the dial input at the MS 1, three exernpIary events may then take place. For example, by inputting a "0" (message 1718}, a Release 1720 of the Call Waiting leg is effectuated between the gateway 2S0 and the VCONl terminal 1304. By inputting a "1" (message 1722), the original two-p~Y connection is ieiminated (Release message 1726) and the MSl 142A may then answer the waiting call (Connect message1728). 13y inputting a "2", the original call is put on hold and the MS answers the waiting call (Connect message 1734).
FIG.16 depicts yet another exemplary emt~odiment of a call waiting ~cenaiio in the WLIP ne~ork portion 1203 wherein MS 11 CI3A receives a call from while in a two-party conference with a terminal, e.;g., the VCON1 terminal 1304. The establishment of the Ariginal twp-patty conference is exemplified by messages 1806. When MS2 1038 places a call, the RNC 13~D sends a Call From message 1808 to the gateway 250. Responsive thereto, a Call Waiting tone 1812 is issued fmm the gateway 250 to MS1_ Thereafter, an ARQ-ACF' messaging session is established between the gateway 250 and the gatekeeper (not shown in this FIG.) so that the gateway 250 stores the ID of the call handler associated with the original two-parry conference. Subseguently, similarto the call waiting events described above, multiple call e~ettts maybe effectuated in this exemplary ennbodimerstby inpu~ing appropriate information at MS 1 103A_ It should be appreciated by those skilled in the art that the #lash agent 203 provided in accordance with the teachings hereiin advantageously converts legacy ANSI-53 messaging used for establishing mufti-party services into appropriate Fi.323 2S messaging usable in a host of VoIP implementatic>ns. It should further be appreciated that the flash agent functionality, which may be suitably i:'itegrated within a gateway or other H.323 components of the network, may also be provided in conjtW
ctiouwith the RNC t 30 disposed in the WLIP network portion 202 that includes suitable protocol translators as disclosed herein with respect to FIG. 2.
Although the systems and methods of the various aspects of the prese~at invention have been described in patlicular reference to the H.323 protocol and ANSI-i, . , ~'O ~~3518 PCT/SE99/02163 4I standards, it should be realized upon reference hereto that the innovative teachings contained herein are not necessarily limited thereto and may be implemented advantageously with any applicable packet-switching protocols and radio telecommunications standards.
S Furthermore, it is believed that the operation .and construction of the various aspects of the present invention will be apparent from the foregoing description.
While the method and system shown and described h<~ve been characterized as being preferred, it will be readily apparent that various changes and modifications could be made therein without departing from the scope of the present invention as set forth in IO the following claims.

Claims (17)

1. WHAT IS CLAIMED IS:
   
   I. An integrated wireless packet-switched network for providing telecommunications services to a mobile subscriber, comprising:
   a packet-switched network portion for transporting communication traffic relating to the mobile subscriber utilizing an Internet Protocol (IP)-based protocol;
   a radio network controller that controls radio access for the mobile subscriber;
   a gateway disposed between the packet-switched network portion and the radio network controller, the gateway including means for switching the communication traffic relating to the mobile subscriber; and a flash proxy agent disposed between the packet-switched network portion and the radio network controller for mapping flash messages from the radio network controller into IP-based messages that implement subscriber services utilizing the packet-switched network portion.
2. 2. The integrated wireless packet-switched network as set forth in claim 1, wherein the network further comprises a first protocol translator for converting Transaction Capability Application Part (TCAP) messaging into IP
   messaging and a second protocol translator for converting Integrated Services Digital Network (ISDN) User Part (ISUP) messaging into Primary Rate Interface (PRI) messaging, the translators being disposed between the gateway and the radio network controller.
3. 3. The integrated wireless packet-switched network as set forth in claim 1, further comprising a Multipoint Control Unit (MCU) disposed between the flash proxy agent and the packet-switched network portion for facilitating through the packet-switched network portion, a multi-party service involving the mobile subscriber.
4. 4. The integrated wireless packet-switched network as set forth in claim 3 wherein the flash proxy agent also maps ANSI-53 messages relating to the multi-party service into IP messages compatible with the MCU.
5. 5. The integrated wireless packet-switched network as set forth in claim 4 wherein the MCU facilitates a multi-party service that includes a call-waiting service.
6. 6. The integrated wireless packet-switched network as set forth in claim 1 wherein the subscriber services implemented utilizing the packet-switched network portion include placing a two-party call on hold while the mobile subscriber makes a call enquiry to a third party and retrieving the two-party call after the call enquiry is completed.
7. 7. A method of registering a mobile terminal in an integrated wireless packet-switched network which includes a cellular network portion and a packet-switched network portion, the cellular network portion including a serving radio network controller (RNC), and the packet-switched network portion including a gatekeeper and a gateway, wherein the gateway includes an Internet Protocol (IP) stack for switching cellular traffic related to the mobile terminal, the method comprising the steps of:
   determining, in the serving RNC, that the mobile terminal is located in a service area associated with the serving RNC;
   responsive to the determining step, sending an Invoke message from the serving RNC to the gateway, wherein a Registration Update signal is encapsulated in the Invoke message;
   upon receiving the Invoke message, sending a Registration Request message from the gateway to the gatekeeper, the Registration Request message including a terminalAlias parameter;
   responsive thereto, sending a Registration Confirm message from the gatekeeper to the gateway if the mobile terminal is successfully registered at the gatekeeper;
   sending a Registration Reject message from the gatekeeper to the gateway if the mobile terminal is not successfully registered at the gatekeeper; and responsive to receiving one of the Registration Confirm and Registration Reject messages, reporting by the gateway, a registration status of the mobile terminal to the RNC.
8. 8. The method of registering a mobile terminal as set forth in claim 7, further comprising the steps of determining, in the gatekeeper, if the mobile terminal has previously registered with the gateway and if so, returning an Admission Confirm message from the gatekeeper to the gateway.
9. 9. The method of registering a mobile terminal as set forth in claim 7, wherein the Return Result message sent from the gateway to the RNC includes a Registration Update Result signal encapsulated therein.
10. 10. A method of de-registering a mobile terminal in an integrated wireless packet-switched network which includes a cellular network portion and a packet-switched network portion, the cellular network portion including a serving radio network controller (RNC), and the packet-switched network portion including a gatekeeper and a gateway, wherein the gateway includes an Internet Protocol (IP) stack for switching cellular traffic related to the mobile terminal, the method comprising the steps of:
    determining, in the serving RNC, that the mobile terminal located in a service area associated with the serving RNC has powered down;
    responsive to the determining step, sending an Invoke message from the serving RNC to the gateway, wherein a Registration Update signal is encapsulated in the Invoke message;
    upon receiving the Invoke message, sending an Unregistration Request message from the gateway to the gatekeeper, the Unregistration Request message including an endpointAlias parameter;
    responsive thereto, sending an Unregistration Confirm message from the gatekeeper to the gateway if the mobile terminal is successfully unregistered at the gatekeeper;
    sending an Unregistration Reject message from the gatekeeper to the gateway if the mobile terminal is not successfully unregistered at the gatekeeper;
    and responsive to receiving one of the Unregistration Confirm and Unregistration Reject messages, reporting by the gateway, a registration status of the mobile terminal to the RNC.
11. 11. The method of de-registering a mobile terminal as set forth in claim 10, wherein the Return Result message sent from the gateway to the RNC
    includes a Registration Update Result signal encapsulated therein.
12. 12. An integrated wireless packet-switched network having a wireless portion and an Internet Protocol (IP) portion, wherein the IP portion includes a gateway, the network comprising:
    
    a radio network controller providing radio access services to a mobile subscriber utilizing circuit-switched protocols;
    means within the gateway for switching communication traffic relating to the mobile subscriber;
    a protocol translator disposed between the gateway and the radio network controller that translates between circuit-switched protocols and the IP
    protocol;
    a Multipoint Control Unit (MCU) for facilitating a multi-party service involving the mobile subscriber; and a flash proxy agent disposed between the MCU and the gateway for mapping flash messages and ANSI-53 messages from the radio network controller into IP messages that enable the MCU to place a two-party call on hold while the mobile subscriber makes a call enquiry to a third party, and to retrieve the two-party call after the call enquiry is completed.
13. 13. The integrated wireless packet-switched network as set forth in claim 12, wherein the flash proxy agent is co-located with the MCU.
14. 14. The integrated wireless packet-switched network as set forth in claim 12, wherein the flash proxy agent is co-located with the gateway.
15. 15. A method for providing a multi-party conference involving a mobile subscriber, a first Internet Protocol (IP) terminal, and a second IP terminal in an integrated wireless packet-switched network having a gateway and a Multipoint Control Unit (MCU), wherein a flash proxy agent is disposed between the gateway and the MCU for mapping ANSI-53 or proprietary flash messages into messages compatible with the MCU, the method comprising the steps of:
    creating, by the first IP terminal, a first conference connection with the mobile subscriber by dialing a first conference password, a first separator and the mobile subscriber's telephone number;
    inviting, by the MCU, the mobile subscriber to the first conference connection;
    creating, by the mobile subscriber, a second call connection with the second IP terminal by dialing a second conference password, a second separator and the second IP terminal's telephone number;
    inviting, by the MCU, the second IP terminal to the second conference connection;
    
    thereafter, releasing the second conference connection between the second IP terminal and the gateway; and toggling between the first and second conference connections by the mobile subscriber until a three-party state is achieved.
16. 16. A method for providing a multi-party conference involving a mobile subscriber, a first Internet Protocol (IP) terminal, and a second IP terminal in an integrated wireless packet-switched network having a gateway and a Multipoint Control Unit (MCU), wherein a flash proxy agent is disposed between the gateway and the MCU for mapping ANSI-53 or proprietary flash messages into messages compatible with the MCU, the method comprising the steps of:
    creating, by the mobile subscriber, a first conference connection with the first IP terminal by dialing a first conference password, a first separator and the first IP terminal's telephone number;
    inviting, by the MCU, the first IP terminal to the first conference connection;
    creating, by the mobile subscriber, a second call connection with the second IP terminal by dialing a second conference password, a second separator and the second IP terminal's telephone number;
    inviting, by the MCU, the second IP terminal to the second conference connection;
    thereafter, releasing the second conference connection between the second IP terminal and the gateway; and toggling between the first and second conference connections by the mobile subscriber until a three-party state is achieved.
17. 17. A method for providing a multi-party conference involving a first mobile subscriber, a second mobile subscriber, and an Internet Protocol (IP) terminal in an integrated wireless packet-switched network having a gateway and a Multipoint Control Unit (MCU), wherein a flash proxy agent is disposed between the gateway and the MCU for mapping ANSI-53 or proprietary flash messages into messages compatible with the MCU, the method comprising the steps of:
    creating, by the first mobile subscriber, a first conference connection with the second mobile subscriber by dialing a first conference password, a first separator and the second mobile subscriber's telephone number;
    inviting, by the MCU, the second mobile subscriber to the first conference connection;
    creating, by the second mobile subscriber, a second call connection with the IP terminal by dialing a second conference password, a second separator and the second IP terminal's telephone number;
    inviting, by the MCU, the second IP terminal to the second conference connection;
    thereafter, releasing the second conference connection between the second IP terminal and the gateway; and toggling between the first and second conference connections by the second mobile subscriber until a three-party state is achieved.