MXPA02001005A - Methods and systems for switching terminals from packet switched service to circuit switched service. - Google Patents

Abstract

Systems and methods for suspending packet switched communications in a user terminal that is configured to operate in both a circuit switched network and a packet switched network. The packet switched network is notified via an interface between the packet switched network and the circuit switched network to suspend communications to a user terminal. This may be accomplished by notifying a gateway node in the circuit switched network that the user terminal is no longer registered in the packet switched network, and by then relaying this information from the gateway node to a control node of the packet switched network via the interface between the networks. The suspend message may be sent in response to the circuit switch network receiving a call origination message from the user terminal, or, alternatively, in response to the circuit switch network receiving an incoming call to the user terminal. In this latter situation, the user terminal may be notified of the incoming call via a page, which the user terminal then responds to via a page response that is sent to the circuit switched network.

Description

tt METHODS AND SYSTEMS FOR SWITCHING SERVICE TERMINALS SWITCHED IN SERVICE PACKAGE SWITCHED ON CIRCUIT FIELD OF THE INVENTION The present invention relates to radiotelephones, and more frequently, to methods and systems for switching radiotelephones between different services.

BACKGROUND OF THE INVENTION As 3S ti in known by those experienced in the field, a communications network is a collection of resources that connects and provides communications between various computers, telephones and -j_5 other network users that are placed in geographically separate locations Cellular telethon networks comprise one of these types of communication network where a plurality of mobile users communicate with each other and, or, cor. other users in a telephone network 20 traditionally through geographically dispersed base stations or "cells" that provide network access to mobile users located within their coverage region. 25 generally analog devices that were largely dedicated to voice communication circuits. These cellular telephones typically operated in "circuit switched" networks, meaning that in response to a call request, the network established a private transmission path (or "channel"! Which was retained for the duration of the call. Consequently, to others. users were not allowed access to the * resources that comprise the transmission path until the full communication has been completed. In recent years, a proliferation of digital cellular phones has developed which, in addition to supporting conventional voice communications, also they support a wide variety of data communications services such as faxes, file transfers between computers, email, call, and the like. For many of these common communications, it is without voice that it can be more efficient to communicate through the network using "switched" communications. in package "as opposed to" switched in circuit "In the networks If packet switched, packets of data (data packets) are transferred from one network user to another network user using a distributed transmission path per network. However, all packets of data comprising a network í * ¡..k. i i * m k í * need for communication does not always use the same transmission path In addition as a particular transmission path in the network is not reserved for any particular communication, many network users may share some or all of the segments that comprise a particular transmission path during the Because of their respective communications In light of the above, cell phones have been developed that support both communications 10 circuit switched and packet switched The users of these telephones can register simultaneously with both a switched network and a packet switched network Typically, if the cellular telephone is "c.e _ =; occupied" (ie it is not coupled in 15 a switched call er circuitoi, "campeara" in the packet switched network While it lives in the packet switched network the cell phone can transmit and receive packet switched data communications When the cell phone user decides When a circuit-switched call is originated, or when another network user calls a circuit-switched call to the cellular telephone, the cellular telephone suspends its packet-switched communications and has access to the circuit-switched network to complete the call. 25 switched circuit i. »i- ~ i ,, -. , -. aüj-üi,. JLÁ k i The Mobile Station Class B136 refers to a cell phone under the IS-136 network protocol that is configured to operate in both, a switched network and a packet switched network. With Class B136 Mobile Stations, circuit switched communications are carried through a switched network in ANSI 41 circuit and packet switched communications are carried through a packet switched network of Radio Packet Service 10 General ("GPRS"). Under the current protocols for Class B136 Mobile, when a circuit switched call request is received for a cell phone that is roaming in the packet switched network, the ANSI 41 network calls (ie, sends a message to) the telephone 15 cellular through a communications link or "interface" that is provided between the ANSI network 31 and the network switched in GPRS packet. Upon receiving the call, the cell phone sends a message of suspension to a GPRS control node that notifies the switched network in 20 GPRS packet that the cell phone is no longer available for packet switched communications According to the existing specifications, this message is sent using an access mode based on containment in a network uplink channel 25 switched in package.

..A • > j Once the suspension test is received and acknowledged, the cellular telephone has access to the Digital Control Channel ("DCCH") of the network switched in ANSI circuit 41, and sends a response to the call to a control node. In that network (the Service Mobile Switching Center or "Service MSC"), then one or more control nodes of the ANSI 41 network operate to connect the circuit switched call. Ideally, cell phone users will experience little or no delay when connecting calls However, in the current Class B136 Cellular phones, a noticeable delay may be present when a cellular telephone that is located in a packet switched network is switched to the switched network in circuit. Accordingly, there is a need for improved methods and systems for switching double service phones from packet switched to circuit switched service.

SUMMARY OF THE INVENTION In view of the above, an object of the present invention is to provide systems and methods that can reduce the time required to switch a user terminal in packet data service mode to circuit switched mode. .tili.lt Another enciop object is proportional systems and methods that calculate the number of control messages transmitted from user terminals to conti ol nodes through limiting cell transmission links and n these and other objects of the present invention are provided μr systems \ methods for switching a user terminal that is configured to terminate in both an on-switched switched network and a switched network in packet switched service packet to circuit switched service According to these systems methods in response to receiving a message When the user terminal is accessing the circuit switched network after I left the network, the network switched in circuit determines toasado in the state of registration of the terminal if the user terminal is accessing the switched network in circuit after leaving the network. If this is the case, the user terminal sends a message of susponsion to the switched network in oaquete via an mt between the packet switched network and the switched network in a qua tified circuit to the network concerned in case it suspends all communications to the user terminal. The methods of suspension systems described herein may be faster than the techniques of the previous branch for rrimutai ne service switched in packet to be ccnmutadc in circuit and in this way can reduce the time required for a user terminal to place or recios a circuit switched call Additionally, the systems and methods cz the present invention they can advantageously reduce the number of control messages that are sent through wireless transmission links between the user terminals and the packet switched network. In a specific embodiment of the present invention, a method of requesting suspension of communications is provided. commuted in a package to a user terminal that is contiguous to operate in both a circuit switched network and a packet switched network According to this method the circuit switched network which responds to the reception of a call connection message of the user terminal determines based on a state of user terminal register s ± the user terminal has switched from the packet-switched area to the circuit-switched network If so, IB circuit-switched network enwa a message of suspension to the packet-switched network through an interta : eitre the switched network in;? rc uto This suspend message can be sent before establishing a call connection for the user terminal In a preferred embodiment of this method, the circuit switched network is an ANSI network 41 having a Service MSC and a gate MSC and the packet switched network is a GPRS network having an SGSN node. In this mode, the Service SMC receives the call connection message from the user terminal, the suspend message is sent by the Gate MSC to the SGSN node through an interface between the ANSI network 41 and the GPRS network , and the step of determining whether the user terminal has switched from the packet switched network to the circuit switched network is performed on the Gate MSC in response to receiving notification that the user terminal has had access to the gateway. ANSI network 41, In preferred embodiments of the invention, this notification may be provided to the MSC by sending an unsolicited response message from the Service MSC to the Gate MSC or by sending a record cancellation message to the Gate MSC. According to an alternative embodiment of the present invention, the methods of switching a user terminal that is configured to operate in both, a network switched in ANSI circuit 41 having a Service MSC and a Gate MSC and a switched network in GPP.S 'packet that has an SGSN node from GPRS communications to ANSI communications are provided. From i * í * t tiAi & ? - .. .., ü \ conformance with these methods the user terminal has access to a control channel in the ANSÍ 41 area, where it can send a message to the Service MSC In response to this message, the MSC can be notified that the user terminal has had access to the ANS network [41 A message of suspension can then be sent from the Gateway MSC to the GPÍS network through an interface between the GPRS network and the ANSÍ 41 network , the GPFS network can suspend packet switched communications to the user terminal and a communication channel ANSI 41 can be distributed to the user terminal. The methods of the present invention can be advantageously employed in mobile systems GPRS-136HS, where the user terminals are mobile cellular user terminals operating in both, a GFRS packet switched network having a Service GPRS Support Node switch node ("SGSN") and a circuit switched network ANSI 4 1 having a Service MSC and a Gate MSC In such cases, the packet switched network and the circuit switched network can be connected through an Gs interface. Additionally, the corresponding systems for carrying out these methods are also provided. k A ". &.» *. t & 1 i,.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic diagram illustrating a user terminal that is simultaneously registered in both, a packet switched network and a circuit switched network; Figure 2 is a flow chart illustrating a method for suspending packet switched communications to a user terminal in accordance with the present invention. Figure 3 is a flow chart illustrating a method of switching a user terminal so double of a packet switched GPRS network to an ANSI 41 circuit switched network according to the present invention, wherein in the ANSI network 41 the Service MSC also acts as the Gate MSC; Figure 4 is a flow chart illustrating a method for switching a dual-mode user terminal of a packet-switched GPRS network to a circuit switched network .ISI 41 in accordance with the present invention, wherein in the ANSI network 41 the Service MSC is separated from the Gate MSC; Figure 5 is a flow chart illustrating a prior art method by which a user places a call to a mobile user in a circuit switched network; , i A * j áÁ * .. Éa & s? .-. l,? Fig. 6 is a schematic diagram illustrating several of the communications that can be used to switch a dual-mode user terminal of a packet-switched GPRS network to the ANSI 41 switched network. circuit in accordance with a mode of the present m / tion where the switch is being made in response to an incoming call and the Door MSC also acts as the Service MSC; Figure 7 is a schematic diagram illustrating several of the communications that can be used to switch a doD mode user terminal of a packet switched GPRS network to the circuit switched ANSI 41 network in accordance with one embodiment of the present invention. where the switching is being done in response to an incoming call 'the Door MSC is separated from the Service MSC Figure d is a schematic diagram illustrating several of the communications that can be used to switch a user terminal in double mode of a packet switched GPRS network to a switched circuit network. INI 41 in accordance with an embodiment of the present invention wherein the switching is being done in response to the user terminal that decides to originate a circuit-switched call, and the Door MSC also acts as the Service MSC, and Figure 9 is a schematic diagram illustrating the vanes of the communications that can be used to switch a dual mode user terminal of a packet switched GPRS network to the circuit switched ANSI 41 network in accordance with one embodiment of the present invention. where the switching is being done in response to the user terminal that decides to originate a circuit switched call, and the Gate MSC is separated from the Service MSC DESCRIPTION D? T? LL.ADA DE L? INVENTION The present invention was described! now more fully below with reference to the accompanying drawings in which the preferred embodiments of the invention are shown. This invention however can be modalized in many different forms and should not be considered as limited to the modalities set forth in FIG. present rather these modalities are provided in such a way that this exposure is clear and complete and completely transcends the scope of the invention to those experienced in the additionally? it will be understood by those of experience in the art that the present invention can be advantageously used in a variety of applications and thus the present invention should not be considered as > This is in no way limited to the example applications described herein. Similar numbers refer to like elements throughout the same. Figure 1 illustrates a communications system in which the methods and systems of the present invention can be used. The communication system of Figure 1 includes a user terminal 10 operating in two different networks 20, 30. A "user terminal" can refer to any ] _Q communications device, such as a telephone, computer, fax machine, etc., however, in a preferred embodiment of the present invention, the user terminal 10 is a mobile cell phone user As shown in the Figure 1, the first of these networks 1 is a packet switched network 20, which, in the example of Figure 1, is a GPRS network. This packet switched network 20 includes one or more control nodes 22 which, in the case of a GPRS network, are typically SGSN nodes. Network 20 switched in packet also includes ur, number of 20 base stations 23, 25, 27, which are the nodes through which the user terminals such as a user terminal 10 can access packet switched network 20, These base stations 23, 25, 27 are typically connected to one or more nodes 22 of 25 control Notice that in Figure 1 the connections between the base stations, control nodes or other network devices in the same "cloud" network are not shown (to simplify the drawing), since these connections will be evident to one of experience in the field in the light of this exposure and the concepts of conventional network connection capacity. When multiple SGSN nodes 22 are employed, each SGSN node 22 will typically be responsible for a specific geographic portion of the packet switched network (i.e., the base stations 23, 25, 27 will be divided between the SGSN nodes 22). The control communications between the packet switched network 20 and the user terminal 10 can logically be transmitted to the birds of a control link 24, which in the case of a GPRS network would typically comprise a control channel. Package ("PCCH") or a Packet Data Channel ("PDCH"). While the PCCH and PDCH are physical links between a base station 23, 25, 27 and a user terminal 10, the link is shown in Figure 1 as going directly from the user terminal 10 to the SGSN node 11 since the base station 23, 25, 27 sends the information carried through these channels 24 to and from the SGSN 22, and in this way there is a "logical" connection directly between the SGSN 22 and the user terminal 10, As shown also in Figure 1, packet switched communications communications between the user terminal 10 and the packet switched reel 20 are carried through the communication channels 26. The GPRS network 'may also include a Home Location and Registration ("IILR") 28, which serves as a centralized data bank for the packet switched network Information regarding various network users, such as terminal 10 and user , is stored in the HLR 23 and can be accessed by the SGSNs 22, As illustrated in Figure 1, the user terminal 10 can also operate in a switched network 30 In the example of Figure 1, the network Circuit-switched circuitry is an ANSI circuit switched network 41 having one or more Service MSCs 32 and one or more Gate MSCs 34. In a network switched in ANSI 41st circuit as the network illustrated in FIG. 1, a plurality of base stations 33, 35, 37 are typically associated with each Service MSC 32. In the illustrative network of FIG. 1, only a single Service MSC 32 is provided, and as such, all three base stations 33, 35, 37 illustrated in Figure 1 would typically be associated with the Service MSC 32 illustrated. As with network 20 switched in GPRS packet, the base stations 33, 35, 37 of the network 30 ANSI 41 - ld they also typically serve as the network access point for user terminals such as user terminal 10. The Service MSC 32 assigned to a base station 33, 35, 37 is typically responsible for performing various control functions associated with the user terminals 10 12 that are having access to the base stations 33, 35, 37 assigned to that base station. Service MSC 32 (these user terminals 10, 12 are "registered" in network 30 with that Service MSC 32). A broadcast signal is typically transmitted by each base station 33, 35, 37 which allows a user terminal 10, 12 to know which base station 33, 35, 37 access, when a user terminal 10, 12 leaves the area from a base station 33, 35, 37 assigned to a first Service MSC 32, and enters the area of a base station assigned to a second Service MSC (n shown in Figure 11, the user terminal registration in the first Service MSC 32 is canceled and set again in the second Service MSC The Gate MSCs 34 provide similar control Junctions with respect to the user terminals 10, 12 that are moving within the switched network 20 package or within other networks (not illustrated in Figure 1) Door MSCs 34 can also perform control functions with respect to the interface 18 between the packet switched network 20 and the switched network 30 in the case of where networks bought In the case of a GPRS packet switched network 20 and an ANSI 41 circuit switched network 30, the interface 13 will typically be implemented as an 18 Gs interface. The circuit switched network ANSI 41 can also include an HLR 39 This HLR can serve as a base for centralized data to network 30 switched in circuit, where information is stored with respect to the various network USLs and can be accessed by Gate MSCs 34 and Service MSCs 32. The control communications between the circuit switched network 30 and the user terminals 10, 12 can logically be transmitted (see the previous discussion regarding logical connections provided in the context of the PCCH / PDCH 24) through a control channel 36. , which in the case of a network switched in ANSI 41 circuit, would typically comprise a Digital Control Channel ("DCCH"). Those of experience in the field will recognize in the light of the present disclosure, however, that these control communications sent through the DCCH could alternatively be transmitted through the ACC. Circuit-switched communications (v gr, telephone calls) between user terminal 10 and -11 circuit switched network 30 is carried through a block of communication channels 38 As shown in Figure 1 circuit switched network 30 will typically be connected to the Public Switched Telephone System "PSTN") 13 An illustrative device such ate a telephone 14 which is connected with hard wire to the PSTN 13 is included in Figure 1 Additionally, the switched network 30 can be connected in addition to other networks 16 switched in circuit (not illustrated in Figure 1) and the packet switched network 0 can be connected to additional packet switched data networks 15 (eg the internet) An illustrated device such as a computer 17 which connects to the packet switched data network 15 is included in the Figure 1 Mobile user terminals 10 having dual-voice capabilities, ie, support switched packet switched and circuit switched switches) can simultaneously register in the packet switched network 20 and the circuit switched network 30 If the user terminal lu is actively operating in the circuit switched network 30 it will typically be registered in that network with one of the Service MSCs 32 Under these conditions, the calls commutated in connection to the user terminal 10 (v.gr, a call from user terminal 12 or telephone 14) are routed to the user terminal 10 via their Service MSC 32 When said circuit switched call 3e completes, the user terminal 10 will typically be opened in the network 20 switched in packet and, therefore, it will be registered with the Door MSC 34 which serves as the Door to the packet switched network 20 When the circuit switched network 30 registers the terminal 10 the user with the Door MSC 34, the registration of the user terminal with the service MSC 32 is canceled In this way, when the user terminal 10 is operating in the packet switched network 20 the Gate MSC 34 serves as the control node in the switched network 30 in circuit responsible for the user LU terminal Ei MSC 34 of Gate then is able to notify the user terminal 10 to leave the switched 2G network in packet when an incoming circuit switched call directed to the user terminal 10 is received through circuit-switched network 30 Similarly, the user terminal 10 is registered with the control node 22 SGSN in network 20 switched in packet Ce this way, node 22 SGSN is responsible for tracking the location of the user terminal 10 when operating in the packet switched mode and is also responsible for the address of the packet switched communications to and from the user terminal 10. Figure 2 is a flow chart illustrating how in a quality of the present invention a device such as the user terminal 10 can switch communication through the packet switched network 20 to the network 30 switched in circuit In the graph ie fluj "of the Figure ^ the user terminal 10 (" User 1") is switching from the service 10 switched in packet to the switched service in response to a call (an "incoming call") placed by another user switched in circuit ("User 2") such as telephone 14 in Figure 1 User 2 places a call ( block 40) by dialing the telephone number 15 of User 1, which results in the incoming call being received in circuit switched network 30 ("CS") (block 42). Typically, this incoming call is received in the form and in call origin message, which is a message that in some way indicates that 20 © 1 User 2 is placing a call. Upon receiving the call origination request from User 2, the circuit switched network 30 sends a call or "notification message" to the switched network 20 in packet ("PS") block 4 4) to request notification 25 of User 1 who is the receiver of a switched call lSmUM »m K? meáb * _ *. ...,, t Ma JJ. ^,., .., -. A "AA ^ A .._. .... - k. a -.AAAA. A.A- JT * J * -. A. - - f, ^ ^ ^^ in incoming circuit The called Eeta is sent through an interface 18 between the switched network 30 and the switched network 20 in packet (Note that as used herein the term "interface" A connection between the two networks carrying control information and other data between the networks is considered. In a typical manner, the interface is implemented on a hard wire communication path or through the telephone network 13 of public connutation. In this way it will be understood that this network interface does not encompass communication transmission paths that use a cellular user terminal 10 as a relay) Ld i ed 0 switched in packet then sends this call or notification message to User 1 (block 46) User 1 is notified of an incoming call from User 2 through network 20 switched in packet instead of through a DCCH channel 36 of network 30 switched on circuit since User 1 is " moving "in the switched network in packet It will be understood by those experts in the field the" warning "or other notification message that is sent from the network 30 switched in circuit to the network 20 switched in packet (ble 44 may differ in form of the warning message "notification message sent in packet") that is sent from network 20 switched in packet to User 1 (block 46). In this way, it will be understood that as used herein, references to 'send' a notification message or a warning ee intended to cover any transmission of the packet switched network 20 instructing User 1 to have access to network 30 switched on circuit or inform User 1 regarding the presence an incoming call switched in circuit, regardless of the level of similarity between the message sent from the network 30 switched in circuit to the network 20 switched in packet and the message sent from the network 20 switched in packet to the rminal 10 user mobile As also shown in Figure 2 upon receiving the packet switched communication message User 1 again establishes a connection with network 30 switched in circuit (block 48 j This is typically done by User 1 having access to a control channel in network 30 switched in circuit Next, network 30 switched in circuit sends a message ae suspension to the network 20 switched in packet that instructs the packet switched network that the network switched in circuit I believe that User 1 na switched from packet switched communications to circuit switched or otherwise provided to the -? . I packet switched network information indicating that the packet switched service to User 1 must be suspended (block 19) The flow chart of Figure 3 illustrates in more detail the operations in accordance with one embodiment of the present invention for a user terminal 10 operating in an area 30 switched in ANSI circuit 41 and a network 20 switched in GPRS packet. In the flow chart in Figure 3, the ANSI 41 network has a single MSC, referred to as a "G / S MSC", which serves as the MSC 32 ele Servi or stops network users and which serves as the MSC 34 Gate As will be appreciated by those skilled in the art, ANSI 41 networks may (but not always) perform the functions of MSC 32 of Servicie and MSC 34 of Gate in different MSCs, and may employ multiple MSCs 32 of Service and / or multiple Door MSCs 34 While Figure 4 and the associated discussion herein provide more detail regarding the implementation of the methods of the present invention in an ANSI 41 network employing a separate Service MSC 32 and Door MSC 34. , it will be observed by those skilled in the art that the systems and methods described and claimed herein can be used in networks switched in ANSI 41 circuit combining the functions of Service and Door in a single MSC, as well as in networks that distribute those functions to multiple MSCs. As shown in Figure 3, the user terminal 10 ("User 1") may decide to switch from packet switched network 20 to circuit switched network 30 because (i) it receives a circuit switched call from another user terminal. such as the user terminals 12, 14 ("user 2, (block 50) or (ii) because User 1 decides to make a circuit switched call (block 82.) In the case where User 2 makes a call to the User 1, operations begin when User 2 dials the number of User 1. sending in this manner a call origin message G / S MSC 32/34 on network 30 switched on circuit (block 52) .Note that more details regarding the substeps associated with block 52 are provided in Figure 5 herein and the text associated therewith.When receiving a call origin message (block 54), the G / S MSC 32/34 determines whether User 1 is currently moving in network 30 switched in ANSI 41 circuit or in network 2 0 switched in GPRS packet (block 56). If the User 1 is moving in the re ANSI 41, the G / S MSC 32/34 may send a warning directly to the User 1 through the control channel 36 of the DCCH of ANSI 41 (BLOCK 58). User 1, who is connected to DCCH 36, then receives the notice ,, Li »i JJ (block 60 j In response to the warning, User 1 transmits a" warning response "message again to the G / S MSC 32/34 through the DCCH (block 62), at which point the G / S S MSC 32/34 can establish a call connection (ie provides the transmission path for the circuit switched call between User 1 and User 2) (block 64) In case User 1 is currently in another When the call is received, the call origination message is received from User 2 in the G / S MSC 32/34, the G / S MSC 32/34 will send a message back to User 2 which results in that User 2 receives a busy signal in response to his call origin request However, in G / S MSC 32/34 determines (block 56) that e ^ User 1 ee is currently moving on the 20 GPRS network then User 1 is notified to reestablish his connection to the network 30 ANSÍ 41. The G / S MSC 32/34 can achieve this by sending an av iso or notification message to the control node SGSN in the network 20 GPRS switched in packet (block 66) Preferably this is achieved by sending the message through the inter face 18 Gs A received this notification message from the network 30 switched on ANSI circuit 41, the SGSN no.222 transmits a packet switched notification message (which could be implemented as a network warning) to User 1, typically through either the PCCH or the PDCH packet control channels 24 ( block 68), upon receiving the packet switched notification message (block 70), User 1 may immediately suspend communications on the packet switched network 20 without informing the node 22 of the SGSN control that is disconnecting from the network 20. GPRS (block 72). When suspending communications in network 20 switched in packet, User 1 has access to control channel 36 DCCH in network 30 switched in circuit ANSI 41 (block 72). Once access is achieved, User 1 sends a warning response message to G / S MSC 32/34 via DCCH 36 (block 74) Upon receiving this message, G / S MSC 32/34 knows that User 1 has reconnected his connection to network 30 switched in circuit ANSI 4] and connects the call between User 2 and User 1 (block 76). While, at this point, the call of User 2 User 1 has been connected, the GPRS network 20 may still not know that User 1 has suspended his communications on network 20 switched in packet, accordingly, the G / S MSC 32/34 sends a notification to the control node 22 SGSN notifying the network 20 switched in GPRS packet that User 1 has suspended its communications in network 20 switched in packet and consequently, all communications switched in packet to User 1 must be suspended (block 78) The G / S MSC 32/34 can achieve this advantageously without any additional message from User 1, and the "suspend" message can be sent visibly through the Id Gs interface, which is typically a hard wire that is not limited in capacity as opposed to sending a message to the SGSN node 22 through (typically) links 10 26 limited in capacity (see Figure 1) Upon receipt of the suspend message, the SGSN node 22 may need to determine if the suspend message is valid (ie if it indicates that a user terminal 10 has left the switched service at package and it has 15 connected to circuit connected service) (block 79) This step may be required because the ANSI network 41 may be configured to automatically send a suspend message at any time when the registration of a user terminal 10 in an MSC 34 ele 2nd Gate is canceled In said network implementation, it is possible to send false ce suspend messages to the node SGSN? V gr when a mobile user terminal 10 moves from one area served by a Gate MSC 34 to the area served by another MSC 34 of Gate) The node 22 SGSN 25 can determine if the suspension of communications tj ^ jdBte ^ aamfí! -iflft? switched in paquste is guaranteed in a variety of ways, including checking the control information (such as that Door MSC 34 sent the suspend message) regarding the network 30 .ANSI 41 sent through the ld Gs interface. If the SGSN node 22 determines that the suspend message is valid (that is, the service must be suspended j, it suspends the packet switched service to the User 1 pending the new registration of User 1 with the network 20 switched in GPRS packet ( block SO) Figure 3 also illustrates a method by which the User could switch from packet switched service to circuit switched service in the event that User 1 decides to place a switched call in a circuit (block 82). shows in Figure 3, if User 1 is already operating or is moving in network 30 of ANSI 41 (decision block 84), all that User 1 needs to do is send a call origin message through the DCCH 36 to G / S MSC 32/34 (block 62), and the call can then be connected (block 64), if instead, (block 84) User 1 is moving on the 20 GPRS network, the User 1 must first exit the package service and have access to the DCCH 36 re d ANSÍ 41 block 72) and the operations proceed as described above for blocks 72, 74. 76 78 SO Note that in block 74 of Figure 3, User 1 sends either a call origin message or a warning response (ie, a response to the notification message notifying User 1 of the incoming call of the User 2) to G / S MSC 32/34 In the present case the term 'call connection message' is used to refer to said message from User 1 to network 30 switched in a donated circuit, the message may be a message from call origin or a warning response As noted above in at least some networks ZO ANSI 41 the Service MSC 32 and the Gate MSC 34 are impregnated in different nodes The iluj chart in Figure 4 illustrates a representative method request suspension of the packet switched service to User 1 / switch User 1 of network 20 switched in packet to network 30 switched in circuit when User 1 wishes to place or receive a circuit switched call in said environment As with Figure 3 shows the graph of flow of Figure 4 assumes that User 1 operates on a network 20 switched in a GFR packet "and in a network 30 switched in an ANSI circuit. 41 However, this particular mode is illustrated only to ensure that the present The disclosure fully explains how the methods of the present invention could be implemented in a representative network, it will be understood that the present invention is not limited to the? mpl < = > GPRS and ANSI 41 network settings As shown in Figure 4, one reason that the user terminal 10 'User 1"may wish to suspend the packet switched communications is because it receives an incoming call As in the example of Figure 3, this occurs for example, when another device ("User 2"? decides to call User 1 (block 90) and then places a call that results in a message originating call being delivered to the network 30 ANSÍ 41 (block 92) A control device or node in the network 30 ANSI 41 (typically a Service MSC 32 that obtains data from network HLR 39 ANSI 41) then determines whether User 1 is currently operating in network 30 ANSI 41 in opposition to for example, moving in the network 20 GPRS i block 94) If the User 1 is currently registered in the network 30 ANSI 41, the call origin message resulting from the placement of the User 2 of the call is delivered to the MSC 32 of Service that eeta assigned to the Us uario 1 fbloque 96) This MSC 32 of Service arrives sends a notice or message to User 1 through DCCH 36 notifying User 1 cte the call (block 93) After User 1 receives the notice (block 100 i User 1 transmits a warning response back to the Service MSC (block 102), recognizing the warning The Service MSC 32 then establishes the connection between the User 1 and the User 2 thus connecting the call (block 104) Yes, in place in the block 94 the Service MSC 32 determines that the User 1 is currently operating in the GPRS network 20 the call origin message is delivered to the Door MSC 34 assigned to User 1 (blosu ~ 106 j This Gate MSC 34 then sends a notification or notification message to the SGSN control node 22 in network 20 switched in GPRS packet, through the 18 Gs interface, which contains information that informs User 1 of the incoming call and / or instructs User 1 to have access to the network 30 ANSÍ 41 (block 108 i control node 22 SGSN _shows this warning (or non-notification message) to User 1 typically via the PCCH, or PDCH 24 (block 110) The message of the MSC 34 from Gate to User 1 which is transmitted through node 22 SGSN control can be sent from a variety of form In one of these ways 'za channel' is sent through SGSN 22 to User 1 This means that SGSN 22 does not know the real contents of the message that is being sent to User 1 - & t £ * • & * but instead you only know that you need to send an underlying message to User 1. By using channeling, it is possible for more autonomy between the 30 ANSI 41 network and the 20 GPRS network, which can advantageously simplify control of the combined system. As noted above, it will also be understood by those in the field that a variety of different messages (m. Packet-switched notification messages) can be sent from Door MSC 34 to User 1 through SGSN 22 to notify the User 1 of an incoming call. Once User 1 receives the notice or message that was sent in response to the call origin of User 2 (block 112), User 1 leaves the GPRS network 20 and accesses DCCH 36 in the ANSÍ 41 network (block 114). ). Since User 1 is receiving a call (block 116) then it sends a warning response through DCCH 36 to its Service MSC 32 (block 118). Since User 1 at this point, however, is still registered with the Gate MSC 34, the Service MSC 32 typically will not wait for a warning response. Accordingly, since the warning response from User 1 was not requested, the Service MSC 32 sends an unsolicited response message (UNSOLRES) to all Door MSCs 34 (block 120) since the unsolicited response _ -., _-? k ik * .J is probably a response to a notice that was sent by a Gate MSC 34 to a user who was not operating in the network 30 ANSÍ 41 This message provides notification to the Gate MSC 34 that the user terminal 10 has access to the network ANSÍ 41 Cerno ee shows in Figure 4, once the MSC 34 of Gate cue was previously assigned to User 1 receives the unsolicited response message can send a suspend message to node 22 SGSN in the network 20 switched in GPRS packet through the 18 Gs interface (block 122)? The one-way MSC 14 does this based on its knowledge that the user terminal 10 is currently registered in the same i, because it was operating in network 20 GPRS), however, it is sending a message to the MSC 3¿ ae Service with which the user terminal 10 is not registered In this way based on the registration status of the user terminal 10 the Port MSC 34 determines that the user terminal 10 h to switch from network 20 GPRS to network 30 switched in circuit Note that in the connection of blocks 120 122, 124 ^ suspend message is generated by network 30 ANSI 41 as opposed to user terminal 10, and that delivery through an interface 18 control between network in opposition through (typically) link j, limited capacity wireless transmission (not shown). This approach is preferred over the alternative approach illustrated in blocks 128, 130, 122 of Figure 4 (wherein the suspend message is sent after the HLR 39 cancels the User 1 registration in the Gate MSC 34), since it expedites the delivery of the suspend message in the GPRS network, and in this manner, it can minimize the amount of packet data traffic that will be sent to User 1 after User 1 has left the network 20 GPRS. In any case, after (or, alternatively, before) the Service MSC 32 sends the unsolicited response message, the Service MSC 32 and the Gate MSC 34 establish the connection between User 1 and User 2 ( blcque 126). At this point (or before establishing the call), Service MSC 32 registers User 1 with HLR 39 ANSI 41 (block 128) HLR 39 then cancels User 1 registration with Door MSC (block 130) Finally, after the Door MSC 34 sends the suspend message to the SGS control node 22? in network 20 GPRe (block 122 i, network 20 GPRS suspends the packet service to User 1 (block 124) Figure 4 also illustrates the operations by which User 1 can switch from commutes.com communications per packet to circuit switched communications in the event that User 1 decides to put a circuit switched call (block 132), as shown in Figure 4, if User 1 is already moving or operating in the ANSI network 41, all that the user 1 needs to do is send a call origin message through the DCCH 36 to the service MSC 32 (block 102), and the call can then be established (blcque 104). (Note, that for the purposes of simplifying the flow chart, a decision block such as the decision block 84 included in Figure 3 was also not included in Figure 4, but it is evidently present) If instead, the User 1 is moving on the GPRS network 20, User 1 must first exit the packet service and have access to the ANCH 41 network DCCH 36 (block 114). Co or User 1 is originating the call (block 116), the call origin message can be sent to Service MSC 32 via DCCH 36 (block 134), and the call is next connected (block 136). Next, blocks 128 130 122 and 124 proceed as described above. Note also that, as in the case of Figure 3, the additional step of having the SGSN control node 22 determine whether the suspend message is valid can be included in the method that is J ^ - '- &-1 illustrated in Figure 4 This determination would occur between blocks 122 and 124 in Figure 4. As illustrated in both Figure 3 and Figure 4. Operations in accordance with various modes of the present invention can be initiated after a user terminal ("User 2") decides to put a Hammock to the mobile user terminal 10 ("User 1"). Figure 5 is a flow chart illustrating additional details of a method possible to notify Service MSC 32 to which User 1 will be assigned upon return to network 30 ANSÍ 41 of the call of User 2 (corresponding to blocks 52 and 54 in Figure 3 and blocks 92 94, 96 and 106 in Figure 4). As shown in Figure 5 after User 2 decides to send a call to User 1 (block 140), User 2 dials the number of User 1 resulting in a call origin message that is sent to a subscriber node. responsible control of the User 2 such as an MSC 32 of the Service (if User 2 is in the network 30 ANSI 41) or a local exchange (if User 2 is in the reel 13 of the public telephone) (block 142j The control node which receives the call origin message then sends the call origin message to the "Home MSC" assigned to User 1 (block 144), where the term "Home MSC" refers to the MSC assigned to , t ii receive call originating messages addressed to the User 1. Co or the Home MSC will typically not follow the location of User 1 when operating in packet switched network 20, upon receipt of this call origination message, the Home MSC sends an address request to the HLR 39 .ANSI 41 (block 146) In response to this address request, the HLF1 39 ANSI 41 sends a request for a telephone location directory number ("TLDN") to the MSC where User 1 is registered (block 148). The MSC to which User 1 is currently registered (which will be Door MSC 34 if User 1 is moving in the 30 GPRS network or a Service MSC 32 if User 1 is registered in the network 30 ANSÍ "41) sends a TLDN to the HLR 39 informing the HLR 39 regarding the location of User 1 (block 150) The HLR 39 then sends the TLDN to the Home MSC for User 1 (block 152), the Home MSC then directs the message of call origin of the User 2 to the MSC of the User 1 (which, if User 1 is moving in the GPRS network 20, is a Gate MSC 34) (block 154), while the systems and methods of the present invention are Particularly useful in mobile cell phone applications, those skilled in the art will be understood as several of the methods and systems described herein may be used in other applications. In this manner, while in a preferred embodiment of the present invention the methods are employed in Class B136 Mobile systems including user terminals operating in both a network 30 switched in ANSI circuit 41 and a network 20 switched in GPFS packet it will be noted that the present The invention can be used in other systems in a dual mode. It will be appreciated by those of experience in the art in light of the teachings of the present disclosure that the methods and systems of the present invention can reduce the time it takes for a terminal 10 user commutes from packet switched service to circuit switched service According to the above method specified for dual mode user terminals 10 operating in a 30 ANSI 41 network and a 20 GPRS network, switching would typically not occur until that a message to suspend the packet switched communications will be sent by the user terminal 10 to the network 20 GPRS This message er This was generally transmitted using a contention-based access mode in the packet switched communications channels 26 and therefore could be subject to considerable delay if the packet switched communications channels 26 are used strongly by others. an air meter for transmitting the suspend notification could result in an extra delay in the warning process In typical network implementations the time required to send a suspend message through containment-based access to the packet switched network 20 it is approximately one second. The other delays if fixed in the above mentioned above switch on the method may include (i) the time required to send the message of origin and call to the MSC 34 of Gate (n) the time it takes for the user terminal 10 having access to the DCCH 36 (approximately one second) / (m) the time required to send the iodization warning The SGSN control to the user terminal 10 (approximately 1 second on average) Thus, the methods and systems of the present invention can reduce the time required to switch to the switched network 30 of? * + 3 seconds to X + 2 seconds, where A is the time required to send the call origin message to the Euthan MSC 34 When the switching is done because User 1 has to originate a call the switching time is reduced from X +2 seconds at X + l seconds In accordance with another aspect of the present invention, the Service MSC 32 and / or the Gate MSC 34 can send a message to the control node SGSN indicating that the packet switched communications to the user terminal 10 must be resumed This message can be sent whenever a suspend message has been previously sent and the dialogue that initiated that suspend message has terminated Once the packet switched service has been resumed successfully. toriately, the user terminal 10 can be 10 informed that it has been resumed either in the release message if the network base station ANSI 41 initiates the release) or in the awareness message of the base station 33, 35 37 (if the user terminal 10 initiates FIGS. 6 to 9 illustrate schematically the message sequences among the various network resources that can be used to achieve a switch from packet switched service to circuit switched service according to various modes of operation.

The present invention Figure and illustrates a sequence of messages that can be used to perform a switch in response to an incoming call to the user terminal 10 when the Service MSC 32 and the Door MSC 34 are ... implemented in the same device Co or 25 is shown in Figure 6, micially terminal 10 of user is moving in network 20 switched in GPRS packet, where it is connected to a base station 27 through PCCH / PDCH 24 (arrow 160) After G / S MSC 32/34 is notified of the incoming call to the user terminal 10, sends a message to the SGSN 22 through the interface 18 Gs i Made 162) This message results in a request for a message sent by the SGSN 22 to the base station 27 [arrow 1 ^ 4 ), from which it was sent to the user terminal 10 (arrow 166) Upon receiving the alert request, the user terminal 10 again establishes its connection to the network 30 ANSI 41 DCCH 36 (arrow 168), and sends a warning response to G / S MSC 34 via DCCH 36 (arrow 170) G / SMSC 23/34 then sends an instruction to suspend the packet service to node 22 of the SGSN control through the 18 Gs interface ( arrow 172), which is then recognized by the SGSN 22 (arrow 174) Next, the G / S MSC 32/34 can request the profile to be vice of the user terminal 10 through a QUA.LPEQ message that is sent to the HLR 39 (arrow 176), and the HLR 39 provides this information through a qualreq message (arrow 178) A Digital Traffic Channel (" DTC ") is then assigned to the user terminal 10 by the G / S MSC 32/34 (arrow 184) and the user terminal 10 is alerted to this assignment (arrow 186). Finally, the user terminal 10 is connects to the incoming call (arrow 188) Figure 7 also illustrates the switching procedure in response to an incoming call except that, in this example, the Gate MSC 34 is not the Service MSC 32. In Figure 7, the switching sequence is identical to that described above with respect to Figure 6 to the point where the user terminal 10 transmits the warning response (arrow 200), except that the Door MSC 34, 10 instead of a combined G / S MSC 32/34, send the message to SGSN 22 (arrow 192). As shown in Figure 7, the response of the user terminal 10 to this warning (arrow 200) is sent to the Service MSC 32 and then the Service MSC 32 and the HLR 39 15 exchanges QUALREQ and qualreq messages (arrows 202 and 204) as previously discussed with respect to arrows 176, 178 184 in Figure 6. A DTC is then assigned to the user terminal 10 by the Service MSC 32 (arrow 206). ). The MSC 32 Service also 20 sends an UNSOLRES message to all of the Gate MSCs 34 (arrow 208) and the Front Gate MSC 34 of the user terminal 10 then sends an instruction to suspend the packet switched communications to the user terminal 10 to SGSN 22 (arrow 25 210), which is then recognized by SGSN (arrow 212) The Door MSC 34 then sends an ISSETUP message to the Service MSC 32 (arrow 220) which requests that the Service MSC 32 perform call set-up actions The Service MSC 32 replies with an issetup message when the actions are completed (arrow 222 j and? MSC 34 of Door establishes the call connection (arrow 24) Finally the MSC 32 of Service alert to the user terminal 10 that the call connection has been established arrow 226) Figures 8 and 9 illustrate a switch sequence that can be followed when the user terminal 10 decides to originate a circuit switched call when it is moving in switched network 20 in packet (arrow 230) When the network 30 .ANSI 41 has a G / S MSC 23/34 combined FIG. 3) the user terminal 10 can simply access the DCCH 36 (arrow 232) and send the origin the call to G / S MS'C 32/34 f arrow 234) The G / S MSC 32/34 then notifies the SGSN 22 that it suspenates the packet service (arrow 236), you can receive a knowledge of the suspension of the SGSN 22 (arrow 23d) then the DTC is assigned and the call is connected (arrows 240, 242) As shown in Figure 9, When the Service and Door MSC functions are not combine the first few events (f_ecnas 250 and 252) are identical to i-. i, t li lae arrows 230 and 232 in Figure 8 Next, however, the call origin message of the user terminal 10 is sent to the Service MSC 32 (arrow 254) Fl MSC 32 of Service can then obtain a service profile of the HLP 39 user terminal 10 in a QUALPEQ message (arrow 256 i) and that information is provided in the qualreq response (arrow 258) Then s ^ assigns a DTC to the call through the Service MSC 32 The Service MSC 32 will then notify the HLR 39 of the new location of the user's go terminal in a REGNOT message (arrow "68) and the HLR 39 will cancel the registration of the user terminal 10 in the Door MSC 34 in a REGCANC message (arrow 270) The Gate MSC 34 will then acknowledge the registration cancellation to the HLR 39 (arrow 276) and the HLR 39 recognizes the registration of the user terminal 10 in the MSC 3"Service in a regnot message. (arrow 2? 8) The present invention has been described in the foregoing c It will be understood that each block of the flow chart illustrations and combinations of blocks in the flow chart illustrations may be included in softwares in this manner while the present invention is described primarily in In terms of methods, those experienced in the field will observe that systems, which will often include software, can be established to implement these methods. Said software would include computer program instructions that can be provided to a processor to produce a machine, so that the instructions executed in the processor create means to implement the functions specified in the block or flow chart blocks. The computer program instructions can be executed by a processor to cause a series of operation steps to be performed by the processor to produce a process implemented by computer so that the instructions executed in the processor provide steps to implement the functions specified in the flow chart block or blocks. Accordingly, the blocks of the flow chart illustrations provided herein support combinations of means for performing the specified functions, combinations of steps for performing the specified functions, and program instruction means for performing the specified functions. It will also be understood that each block of the flow chart illustrations, and combinations of blocks in the flow chart illustrations, is 7 ^? * T. i i. They can be implemented through special purpose hardware-based systems that perform specific functions or steps, or combinations of special-purpose hardware and computer instructions. It will also be noted that the means to perform the specified functions can be placed in any of a variety of network resources, and further that in many cases it will be more efficient to distribute the logic forming the system in a number of nodes in the switched relays in package and circuit switched In the drawings, specification and examples, typical preferred embodiments of the invention have been described and, even when specific terms are employed these terms are used in a generic and descriptive sense only and not for purposes of limiting the scope of the invention. the invention being set forth in the following claims.

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Claims (3)

1. - A method for requesting suspension of packet switched communications to a user terminal that is configured to operate in both, a circuit switched network and a packet switched network, the method comprising the steps carried out by the circuit switched network of: receiving a call connection message from the user terminal; determining, based on a registration status of the user terminal, whether the user terminal has switched from the packet switched network to the circuit switched network in response to the received call connection message; and sending a suspend message from the circuit switched network to the packet switched network through a switch between the circuit switched network and the packet switched network if the user terminal has switched from the packet switched network to the switched network. circuit switched network.

2. The method according to claim 1, wherein the step of sending a suspend message is followed by the step of establishing a call connection for the user terminal. . ^ le- ^^ 3 - The net according to claim 1, wherein the circuit switched network is an ANSI network 41 having a Service MSC and a Gate MSC and the packet switched network is a GPRS network which has an SGSN node, wherein the receiving step comprises the step of receiving a call connection message from the user terminal in the Service MSC; and wherein the step of sending comprises the step of sending a suspend message from the Door MSC to the SGSN node through an in-line between the ANSI network 41 and the GPRS network. 4 - The method according to claim 3, wherein the step of determining comprises the step of: providing notification to the Door MSC that the user terminal has had access to the ANSÍ 41 network, and determining in the Door MSC based in the notification and registration status of the user terminal that the user terminal has switched from the packet switched network to the circuit switched network 5 - The method according to claim 4, wherein the step of providing notification includes the step of sending a message of unsolicited response of the MSC Service to the Door MSC in response to the reception of the call connection message 6 - The method according to claim 4 wherein the step of providing notification comprises the steps of registering the user terminal with the Service MSC, and send a registration cancellation message to the MSC of Gate 7 - The method according to claim 1 wherein the receiving step comprises the step of receiving a call origin message from the user terminal 8 - The method according to claim 1 wherein the receiving step is preceded by the steps performed by the circuit switched network to receive an incoming call to the user terminal in a circuit switched network, transmitting a notification message of the circuit-switched network to the packet-switched network through the interface between the circuit-switched network and the packet-switched network to the user terminal accessing the circuit switched network, and wherein the receiving step comprises the step of receiving a response to the notification message from the user terminal; and further comprising the step performed by the packet switched network of sending the notification message of the packet switched network to the user terminal 9 - The method according to claim 8 wherein the step of transmitting a notification message comprises the step of transmitting a notification message from the Door MSC to the SGSN via a Ge interface, and wherein the step of sending the notification message comprises the step of transmitting a packet-switched notification message from the SGSN to the terminal 10 - The method according to claim 9 wherein the step of transmitting a packet-switched notification message from the SGSN to the user terminal comprises the step of channeling the notification message sent by the Gate MSC to the terminal of the user in the packet-switched notification message transmitted by the SGSN. 11 - A method for switching a user terminal that is configured to operate on both, a mm¡m i A. *? _tit. i, 1 L-at network switched in ANSI circuit 41 having a Service MSC and a Gate M? C and a packet switched network GPPS having an SGSN node of GPRS communications to ANSI communication 41 the method comprising the steps of access to the user terminal a control channel in the network ANSI 41 send a message from the user terminal to the service MSC provide notification to the gate MSC that the user terminal has had access to the network ANSI 41 a suspend message from the Gateway MSC to the GPRS ed and through an intertation between the GPRS network and the ANSÍ 41 network in response to receiving the notification in the Gate MSC to suspend the packet switched communications between the GPRS network and the terminal terminal of the user responding to receiving the suspend message from the ANSI 1 network, and distributing an ANSI 41 communication channel to the user terminal 12 - The method according to claim 11 wherein the step provided r notification to Puerta MSC comprises the burden of sending an unsolicited response message from the Service MSC . t? .... To L ?. tj. , Jt a. .i .. jt ^ t »iil ^ t to the Gate MSC in response to the user terminal that sends the message to the Service MSC. 13 - The method according to claim 12, wherein the step of providing notification to the Door MSC comprises the steps of: registering the user terminal with the Service MSC; and canceling a record from the user terminal in the Gate MSC 14. The method according to claim 11, wherein the access step is preceded by the passage of the user terminal that decides to originate a call in the network ANSI 41 and where the message sent from the terminal of The user to the Service MSC comprises a message; e of origin of 1 call. The method according to claim 11, wherein the access step is preceded by the steps of: receiving an incoming call to the user terminal in the network ANSI 41; notify the user terminal of the incoming call; and where the message sent from the terminal of 25 user to the Service MSC comprises a response from Notice 16 - The method according to claim 15, wherein the step of notifying the user terminal of the incoming call comprises the steps of transmitting a notification message of the Door MSC the SGSN through the network interface. GPRS and the ANSI network 11, and transmit a packet-switched notification message from the SGSN to the user terminal 17 - The method according to claim 16 wherein the step of transmitting a packet switched notification message from the SGSN to the The user terminal comprises the step of channeling the notification message sent by the gate MSC to the user terminal in the packet switched notification message transmitted by the SGSN 18 - The method according to claim 12, further comprising the step of determining in the GPFS network whether the suspend message indicates that the user terminal has accessed the network ANSI 41, and where the step of suspending comprises the step of suspending tomuní cacicnee switched in packet between the GPRS network and the user terminal in response to receiving k & . i. . - * a * S i fc ^ ^^ 3.- the suspend message of the Gate MSC in the case that the GPRS network determines in the determination step that the user terminal has had access to the network ANSÍ 41 19 - A system for requesting the suspension of packet switched communications to a user terminal that is configured to operate in both a circuit switched network and a packet switched network, the system comprising means for receiving a call connection message from the user terminal means for determining based on a registration status of the user terminal if the user terminal has switched from the packet switched network to the circuit switching network, and means for sending a suspend message of the switched network in circuit to the packet switched network through an interface between the circuit switched network and the packet switched network if the user terminal has switched from the packet switched network to the circuit switched network