JP2008533761A - Communication method and communication system - Google Patents

Abstract

  Nomadic servers and related systems enable seamless roaming of mobile communication devices between different types of wireless networks for voice, data and video communications, such as WiFi networks and mobile networks. By using a nomadic server, a combination of WiFi and mobile networks can be used to provide access to mobile communication devices and, where possible, calls can be switched using a VoIP network. Nomadic server is a telephone communication processing and exchange server that "maintains" ongoing telephone communications without interruption and roams between WiFi access points and mobile networks without interrupting ongoing communications. is there. For example, by using a nomadic server, telephone communication can be seamlessly switched between VoIP and a cellular phone network. The nomadic server provides a switch on the interface to perform handoff between the VoIP and mobile networks. With this technology, telephone communication via the VoIP network can be switched to telephone communication via WiFi or a mobile network where possible.

Description

Related applications

  This application is filed by the same inventor with the priority of US Provisional Patent Application No. 60 / 643,829 filed January 14, 2005, entitled “TELEPHONE COMMUNICATIONS PROCESSING CONTROLLER”. Insist. US Provisional Patent Application No. 60 / 643,829, filed Jan. 14, 2005, entitled "TELEPHONE COMMUNICATIONS PROCESSING CONTROLLER" is hereby incorporated by reference in its entirety. . This application is also incorporated by reference in this application, US patent application Ser. No. 11 / 031,498, filed Jan. 6, 2005, entitled “Automatic between Mobile Network and VoIP Network”. This is a partial continuation application for “TELEPHONE WITH AUTOMATIC SWITCHING BETWEEN CELLULAR AND VOIP NETWORKS”. US patent application Ser. No. 11 / 031,498 is incorporated by reference in this application, US provisional application No. 60 / 534,466, filed Jan. 6, 2004, entitled “WI- Use the FI signal strength value to give priority to “Radiotelephone with automatic mattress and Wi-Fi networking USING WI-FI SIGNAL STRENGTH VALUES” Insist.

  The present invention relates to a communication method and a communication system. More particularly, the present invention relates to seamless switching of communications among voice over internet protocol (VoIP), land mobile communication networks and public circuit switched networks.

  Currently, telephone communications are performed over wireless mobile networks such as GSM, CDMA and CDMA2000, Voice over Internet Protocol (VoIP), or circuit switched networks such as the public switched telephone network (PSTN). Yes. With current technology, telephones used in these networks are often limited to use in one particular network. For example, a mobile telephone operates in a mobile network, a VoIP telephone operates in a VoIP network, and a fixed telephone operates in a circuit switched network. Such a limitation means that in-progress telephone communications cannot be seamlessly switched between mobile networks, VoIP networks and circuit switched networks without breaking the connection.

  In such wireless networks, many users share some of the allowed bandwidth of the wireless spectrum. The cost of the wireless network infrastructure is relatively high due to the size and complexity of the network equipment. There are various performance differences between different wireless networks. For example, conventional wireless mobile networks cover a relatively large geographic area but have a low bandwidth. Other wireless networks, such as CDMA2000-EV-DO / DV networks, use higher bandwidth to provide more advanced data services such as web browsing. In these networks, many users share part of the spectrum limited to a relatively narrow bandwidth. In addition, there are high-speed wireless networks with improved spectral efficiency and a small communication range. For example, an IEEE 802.11x (or WiFi) network uses Direct Sequence Spread Spectrum (DSSS) mode to transmit data at a rate of up to 11 Mbps, and Orthogonal Frequency Division Multiplexing: OFDM) mode is used to transmit data at a maximum rate of 54 Mbps.

  Network wireless access points compliant with WiFi (eg, IEEE 802.11b) networks cover a range of diameters of several hundred feet. Each such network access point is connected to a larger network (eg, the Internet). For example, in WiFi / VoIP (Wireless Federity / Voice over Internet Protocol), a user of a communication device can use IEEE 802. Using the technology specified by xx, it is possible to make a wireless telephone call via the Internet. VoIP is a technology that converts an analog audio signal into digital data that can be transmitted via the Internet. Conventional VoIP telephony is established by a VoIP network carrier that makes calls based on VoIP using a VoIP network (eg, the Internet). VoIP enabled networks and VoIP compatible networks include VoIP switching for proper routing and charging of VoIP based calls.

  To cover a larger geographic area, a relatively large number of IEEE 802.11x network access points and a relatively large wired backhaul network are required. Also, due in part to the relatively small geographic coverage of each network access point, a network based on IEEE 802.11x may be too expensive to set up. Furthermore, since the communication range is small, there may be many “dead zones” in which a user of a mobile communication device cannot make a call using a VoIP network.

  A conventional VoIP telephone that operates within a WiFi communication range (hot spot) corresponding to a WiFi access point has a relatively low telephone communication fee. However, the availability of WiFi is limited because the geographic area supported by each WiFi access point is small.

  Conventional mobile telephones that operate within the cell communication range have relatively high telephone charges and limited multimedia capabilities. Mobile networks and network availability cover a wider and larger geographic area.

  For example, a conventional fixed telephone that operates in a circuit switching network provided in many residences does not provide a large-scale telephone communication function such as video communication. Furthermore, such a fixed telephone cannot be used while moving, such as a VoIP telephone or a mobile telephone.

  The present invention provides an interface called a nomadic server that realizes seamless roaming of mobile communication devices between different types of wireless networks for voice communication, data communication, and video communication, such as a WiFi network and a mobile network. A server and related systems are provided. By using a nomadic server, a combination of WiFi and mobile networks can be used to provide access to mobile communication devices and, where possible, calls can be switched using a VoIP network.

  The nomadic server “holds” ongoing telephone communications without interruption, and roams between the WiFi access point and the mobile network without breaking in-progress communications. A telephone communication processing and exchange server to be performed. For example, by using a nomadic server, telephone communication can be seamlessly switched between VoIP and a cellular phone network. The nomadic server provides a switch on the interface to perform handoff between the VoIP and mobile networks. With this technology, telephone communication via the VoIP network can be switched to telephone communication via WiFi or a mobile network where possible.

  In one aspect of the present invention, the present invention provides a communication method for realizing communication for a mobile communication device moving between a plurality of different types of wireless networks. A communication method establishes a first communication link between a mobile communication device and a final destination device, including a first wireless communication link between the mobile communication device and a first type of wireless network. And monitoring the signal strength of the first wireless communication link, and establishing a second communication link between the interface server and the final destination device if the signal strength falls below a predetermined threshold A step of notifying the mobile communication device that communication via the first communication link has ended; and by redirecting the second communication link from the interface server to the mobile communication device; Establishing a second wireless communication link with a second type of wireless network. The first type of wireless communication link may include a WiFi communication link, and the first type of wireless network may include a WiFi network access point. The second type of wireless network may include a wireless mobile network. Establishment of the first communication link may include routing through a VoIP network. Establishment of the first communication link may include routing through the mobile network. Establishment of the second communication link may include routing through the VoIP network. Establishment of the second communication link may include routing through the mobile network.

  The communication method may further include a step of providing information representing a connection state from the mobile communication device to the interface server when the mobile communication device is within the first communication range of the first type wireless network. Good. The communication method may further include providing routing association information for associating the mobile communication device with the interface server to the mobile switching center in the second type of wireless network. Furthermore, when the connection state becomes valid, the communication method routes termination communication information destined for the mobile communication device from the mobile switching center to the interface server based on the routing association information, and sets the first type of wireless network. Via the interface server, the terminal communication information may be routed from the interface server to the mobile communication device. The communication method may further include a step of deleting the routing association information from the mobile switching center when the connection state is not provided to the interface server. The communication method may further include the step of registering the mobile communication device with the mobile switching center in the second type wireless network when the signal strength falls below a predetermined threshold. The communication method may further include a step of setting up a second communication link with a final destination device and transmitting information regarding the second communication link to the interface server.

  As another aspect, the present invention provides a communication method for realizing communication for a mobile communication device moving between a plurality of WiFi communication ranges. The communication method associates a mobile communication device with a nomadic server connected to one or more WiFi access points, and establishes a first WiFi communication link between the mobile communication device and the first WiFi access point. Based on the step, supplying the IP address of the first WiFi access point to the nomadic server, registering the mobile communication device in the nomadic server, and the IP address of the first WiFi access point and the first WiFi communication link Configuring a communication path to the mobile communication device via the nomadic server, detecting a movement of the mobile communication device to the communication range of the second WiFi access point, and an IP address of the second WiFi access point Including nomadic sa Registering the mobile communication device in the network, establishing a second WiFi communication link between the mobile communication device and the second WiFi access point, the IP address of the second WiFi access point, and the second Reconfiguring the communication path based on the WiFi communication link. The communication method may further include the step of associating the mobile communication device with the nomadic server at the mobile switching center. The communication method may further include providing routing association information for associating the mobile communication device with the interface server to the mobile switching center in the mobile network. The communication method routes end communication information destined for the mobile communication device from the mobile switching center to the interface server based on the routing association information, and transmits the end communication information from the interface server to the mobile communication device via the communication path. There may be a step of routing. Registering the mobile communication device with the nomadic server may include providing a connection state of the mobile communication device while the mobile communication device is within a specific communication range of a specific WiFi access point.

  As yet another aspect, the present invention provides a communication system that implements communication for mobile communication devices moving between a plurality of different types of wireless networks. The communication system is connected to a plurality of different types of wireless networks, a mobile communication device configured to access the plurality of wireless networks, and the plurality of wireless networks, and the mobile communication device is a first type of wireless network. Maintaining a seamless communication link between the mobile communication device and the final destination device when moving from the associated first wireless communication range to the second wireless communication range associated with the second type of wireless network The first interface over the second type of wireless network while the first communication link between the mobile communication device and the final destination device over the first type of wireless network is active. A second routed to the mobile communication device is set up to be transmitted to the server and terminated when the first communication link is terminated. And an interface server to establish a trust link. The first communication link may include a first wireless communication link between the mobile communication device and the first type of wireless network. The first wireless communication range may include a WiFi communication range, and the first wireless communication link may include a WiFi communication link between the mobile communication device and the WiFi access point. The first communication link may include a routing path through the VoIP network. The first communication link may include a routing path through the mobile network. The second communication link may include a second wireless communication link between the mobile communication device and the second type of wireless network. The second wireless communication range may include a cell communication range, and the second wireless communication link may include a wireless mobile communication link between the mobile communication device and the base station. The second communication link may include a routing path through the VoIP network. The second communication link may include a routing path through the mobile network. The second type of wireless network may include a wireless mobile network.

  As a further aspect, the present invention provides a mobile communication device that moves from a first wireless communication range associated with a first type of wireless network to a second wireless communication range associated with a second type of wireless network. A first communication link between the mobile communication device and the final destination device over a first type of wireless network, maintaining a seamless communication link between the mobile communication device and the final destination device Is set up to be transmitted to the interface server first via the second type of wireless network while the first communication link is terminated and the second routed to the mobile communication device. An interface server for establishing a communication link is provided. The interface server may further comprise a first inter-network functional block that maintains current configuration and state information associated with the first communication link. The first wireless communication range may include a WiFi communication range, and the first communication link may include a WiFi communication link between the mobile communication device and the WiFi access point. The interface server may further comprise a second inter-network functional block that maintains current configuration and state information associated with the second communication link. The interface server may further include a provisioning server that supplies setting information to the mobile communication device.

  According to the embodiment of the nomadic server, for example, in the range of a VoIP access point such as a WiFi hotspot, telephone communication is started using VoIP, and in the cell range and outside the range of the VoIP access point, a mobile network is used. You can start telephone communication. When the caller moves out of range of the VoIP access point, the nomadic server “maintains” the current telephone communication and switches from the VoIP access point to the mobile network. Similarly, if the caller moves within the range of the VoIP access point while performing telephone communication via the mobile network, the nomadic server “maintains” the current telephone communication and switches from the mobile network to the VoIP access point. . A nomadic server remains operational or valid for telephone communications while switching from one network to another. When the switching is finished, the nomadic server is released from the telephone communication.

  FIG. 1 illustrates an exemplary system of interconnected networks, where a nomadic server 80 is connected to a mobile network, a wireless IP network, and a public switched telephone network (PSTN) 60. Yes. The mobile network shown in FIG. 1 includes a mobile switching center 20 connected to a land land mobile network (PLMN) 30 and a plurality of base stations 10 connected to the mobile switching center 20. The mobile network architecture shown in FIG. 1 has been simplified for clarity of explanation. For example, the mobile network of FIG. 1 has only a single mobile switching center, but the mobile network may include multiple switching centers. Further, it will be apparent to those skilled in the art that the mobile switching center functionality may be incorporated into a base station or any other mobile network infrastructure or nomadic server. Accordingly, the term mobile switching center as used herein shall refer to any suitable equipment that performs the functions of the mobile switching center within the infrastructure of the mobile switching center and mobile network equipment. FIG. 1 shows four base stations 10 connected to the mobile switching center 20. Alternatively, more or less than four base stations may be connected to each mobile switching center.

  The wireless IP network shown in FIG. 1 includes a plurality of IP wireless access points 40 connected to the Internet 50. Specific examples of IP access points include, but are not limited to, wireless or wired broadband termination elements, wireless or wired modems, wireless or wired routers, and WiFi access points.

  In this specific example, the nomadic server 80 is connected to the PSTN 60 via the soft switch 70. The soft switch 70 provides the nomadic server 80 with an interface to an old network such as PSTN.

  The mobile communication device 90 is preferably a dual-mode telephone that provides VoIP client functionality over a WiFi network and GSM / CDMA mobile phone functionality over a mobile network. Also, the mobile communication device 90 can be configured to automatically switch existing communications from a mobile network to a wireless IP network, or automatically switch existing communications from an IP network to a mobile network. Such a mobile communication device is described in US patent application Ser. No. 11 / 031,498, filed Jan. 6, 2005, incorporated herein by reference, entitled “Between mobile network and VoIP network”. Is also disclosed in “TELEPHONE WITH AUTOMATIC SWITCHING BETWEEN CELLULAR AND VOIP NETWORKS”. Alternatives to mobile communication devices include, but are not limited to, laptop computers, music players / recorders, PDAs, telephones, or any existing mobile communication device that can receive broadband content via a wireless connection. included.

  FIG. 2 shows a simplified high-level block diagram of one embodiment of mobile communication device 90. The mobile communication device 90 includes a WiFi processing unit and a cell processing unit. The cell processing unit uses either GSM or CDMA, and access to the communication network is established via the nearest base station 10. The WiFi processing unit uses the VoIP client to start and end communication via the WiFi network. The mobile communication device 90 is configured to automatically switch communication between the mobile network and the VoIP network. The mobile communication device 90 includes a mobile communication module 93 connected to the cell antenna 91, a WiFi communication module 94 connected to the WiFi antenna 92, an audio / video amplifier 95, a network switch unit 96, a timer unit 97, A WiFi signal level intensity monitor 98, a microphone 100, a speaker 99, and a display monitor 101 are provided. The mobile communication device 90 communicates via the mobile communication module 93 connected to the base station 10 (FIG. 1) and / or via the WiFi communication module 94 connected to the WiFi wireless access point 40 (FIG. 1). Establish and maintain The mobile communication module 93 also includes a transceiver 102 that receives / transmits signals to / from the mobile network. In addition, the WiFi communication module 94 includes a transceiver 103 that receives / transmits signals from / to the IP network. Depending on the level of the WiFi signal transmitted and detected from the WiFi access point, a call previously established via the mobile communication module 93 can be switched to be processed by the WiFi communication module 94, and first Calls established via the WiFi communication module 94 can be switched to be processed by the mobile communication module 93.

  The nomadic server 80 shown in FIG. 1 has one wireless access when the mobile communication device 90 moves from one WiFi communication range to another WiFi communication range, or moves outside the WiFi communication range within the mobile network communication range. Realize seamless handoff from point to other wireless access points. The nomadic server 80 includes a provisioning server (PS) in which a cellular inter-working function (CIWF) block 82 and a WiFi inter-working function (WIWF) block 84 are incorporated. 86. The nomadic server 80 and the mobile switching center 20 are connected “tightly” or “loosely”. In the case of being tightly connected, the nomadic server 80 and the mobile switching center 20 are connected to a local area network (LAN), a wide area network (WAN), or a dedicated or non-existent mobile switching center 20. When connected by some other suitable interface using a dedicated interface. In this case, the nomadic server 80 can communicate with the mobile switching center 20 via these interfaces. In the loosely connected case, the nomadic server 80 and the mobile switching center 20 are connected using an integrated services digital network (ISDN) trunk or soft switch, or some other suitable interface. Refers to the case. In this context, a soft switch is defined as a media gateway controller, call agent, gatekeeper, etc. used to control the connection at the connection point between the circuit and the packet network.

  The nomadic server 80 is connected to one or more mobile switching centers 20 for communication signaling and media traffic. A point of interconnection (PoI) is formed between each mobile switching center 20 and the nomadic server 80. In any network, one or more nomadic servers 80 can be provided. Each mobile communication device 90 is connected to a home nomadic server, in this specific example, a nomadic server 80. Each nomadic server may be a home nomadic server for one or more mobile communication devices. The mobile switching center is preferably connected to only one nomadic server and the home mobile switching center is connected to the home nomadic server. In this way, the mobile communication device is associated with the home mobile switching center. Alternatively, a plurality of mobile switching centers may be connected to a predetermined arbitrary nomadic server.

  When the mobile communication device 90 places a call within the WiFi communication range, the nomadic server 80 establishes a WiFi communication link. The nomadic server 80 establishes a call via a mobile network or a VoIP network. When a call is established via the mobile network, the call is routed through the mobile switching center connected to the nomadic server 80. If the call is established over a VoIP network, the call is routed through the service provider's soft switch 70 using Session Initiation Protocol (SIP) or some other suitable protocol such as H323. The In other words, if the mobile communication device 90 is located within the WiFi communication range, the first leg of the call is routed via the WiFi communication link, and the rest of the call can be made to the mobile network, VoIP network or PSTN. Can be routed via any of these.

  In actual operation, an initial call is established by the mobile communication device 90 by determining whether the mobile communication device 90 is within WiFi coverage. Such a determination is preferably performed by measuring signal strength or using other metrics of the nearest WiFi wireless access point 40, if the signal strength or other metrics exceed a predetermined threshold. WiFi communication link is established. When the WiFi access point cannot be used, the mobile communication device 90 establishes a mobile communication link with the nearest base station 10. When the mobile communication device 90 first establishes a WiFi communication link, the mobile communication device 90 establishes a communication link with the provisioning server 86 via the WiFi communication link. The WiFi communication link includes a WiFi wireless access point 40 and the Internet 50. The provisioning server 86 provides the mobile communication device 90 with setting information including identification information of the home nomadic server which is the nomadic server 80 in this specific example. The mobile communication device 90 preferably communicates with the provisioning server 86 via the Internet 50 using SSL-based XML.

  In addition, the mobile communication device 90 is registered in the nomadic server 80. In some embodiments, authentication is performed between the mobile communication device 90 and the nomadic server 80 using a SIP registration method or other suitable protocol such as H323. Further, the nomadic server 80 maintains the setting information of the mobile switching center 20. The nomadic server 80 updates the mobile switching center 20 with the current position of the mobile communication device 90. The current position is information that refers to a WiFi access point related to the WiFi communication range in which the mobile communication device 90 is currently located. The nomadic server 80 periodically updates the mobile switching center 20 according to the position of the mobile communication device 90. Thereby, the mobile switching center 20 maintains information regarding the current position of the mobile communication device 90. Using this location information, a call received via the mobile network of the mobile communication device 90 is routed from the mobile switching center 20 via the nomadic server 80 to the WiFi communication link.

  As long as the mobile communication device 90 maintains the WiFi communication link by the wireless access point 40, the mobile communication device 90 is registered with the home nomadic server, in this case, the nomadic server 80, regardless of the communication range of the mobile network. On the other hand, the nomadic server 80 updates the current position of the mobile communication device 90 in the mobile switching center 20. When the signal strength or other evaluation criteria of the WiFi communication link weakens and falls below a predetermined threshold, the mobile communication device 90 notifies the nomadic server 80 of this. In response to this, the nomadic server 80 stops sending the location update information to the mobile switching center 20. Furthermore, the mobile communication device 90 stops sending the SIP registration to the nomadic server 80, and the mobile communication device 90 starts registration with the nearest mobile switching center. In this way, calls originating from or destined for the mobile communication device 90 will be processed by the mobile switching center. The nearest mobile switching center may be the home mobile switching center of the mobile communication device 90 or may be another mobile switching center called a visitor mobile switching center in the mobile network.

  At this point, a first call has been established over the WiFi communication link, but the mobile communication device 90 is currently destined for the same final destination as the first call established over the WiFi communication link. Set up a second call and establish a mobile communication link. When the mobile communication link is established via the home mobile switching center, the second call is routed to the nomadic server 80 via the PoI between the home mobile switching center and the nomadic server 80. In response, the nomadic server 80 determines whether the first call over the WiFi communication link is still in progress. If this is the case, the nomadic server 80 switches access from the WiFi communication link to the mobile communication link.

  On the other hand, when the mobile communication link is established via the visitor mobile switching center, the visitor mobile switching center transmits a second call to the visitor nomadic server connected to the visitor mobile switching center. The visitor nomadic server cannot determine the state of the first call over the WiFi communication link, so the visitor nomadic server switches the second call to the final destination. At the same time, the home nomadic server that has received the notification regarding the disconnection of the WiFi communication link from the mobile communication device 90 first waits for a connection request for establishing a second call from the home mobile switching center. However, since the second call is being processed by the visitor nomadic server, the home nomadic server does not receive such a connection request. Thus, the home nomadic server deletes the first call on the WiFi communication link and the second call is maintained by the mobile communication device 90 via the mobile communication link.

  Once a mobile communication link is established between the mobile communication device 90 and the nearest mobile switching center, the mobile communication device 90 does not attempt to establish another WiFi communication link even when reentering the WiFi communication range. . The mobile communication device 90 attempts to access the WiFi communication link when the mobile communication device 90 returns to the idle state.

  When the mobile communication device moves from the first communication range to the second communication range, the transition process differs depending on the type of the second communication range and the original call setup configuration. The movement from the first communication range to the second communication range usually corresponds to one of five different scenarios each corresponding to a different transition process.

  The first scenario is a scenario in which the mobile communication device moves from the first WiFi communication range to the second WiFi communication range. The first WiFi communication range is associated with the first WiFi access point, and the second WiFi communication range is associated with the second WiFi access point. Each WiFi access point has an IP address. If the mobile communication device is within the first WiFi communication range, the mobile communication device registers with the home nomadic server via the first WiFi access point. The home nomadic server updates the position of the mobile communication device with the home mobile switching center of the mobile communication device. For incoming calls destined for the mobile communication device, the home mobile switching center routes the call to the home nomadic server based on the latest location information.

  When the mobile communication device moves to the second WiFi communication range, the mobile communication device detects a transition. The mobile communication device acquires an IP address from the second WiFi access point, and transmits information indicating the change of the IP address to the provisioning server of the home nomadic server. Further, the mobile communication device transmits a SIP register message with a new IP address to the home nomadic server. In response, the home nomadic server redirects all incoming calls to the IP address of the second WiFi access point. The position of the mobile communication device maintained by the home mobile switching center is still valid.

  The second scenario is that the mobile communication device 90 initiates a call within the first WiFi communication range, sets up the call over the VoIP network, and from the first WiFi communication range, the home mobile switching of the mobile communication device 90 This is a scenario of moving to a cell communication range supported by a station. In this scenario, the mobile communication device 90 moves from the first WiFi communication range to the non-WiFi communication range. When the first call is initiated and set up, a WiFi communication link is established between the mobile communication device and the first wireless access point associated with the first WiFi coverage area. If the mobile communication device is within the first WiFi communication range, the mobile communication device registers with the home nomadic server via the first WiFi access point. The first call is routed from the first wireless access point via a VoIP network such as the Internet.

  The mobile communication device monitors the signal strength or other criteria of the WiFi communication link. When the signal strength or other evaluation criteria falls below a predetermined threshold, the mobile communication device registers with the nearest mobile switching center that is the home mobile switching center of the mobile communication device in this second scenario. The mobile communication device also sends a call setup request to the home mobile switching center for the second call to the same final destination as the first call. The second call is set up by the home mobile switching center and routed to the CIWF block in the home nomadic server. The CIWF block determines from the WIWF block whether a first call is in progress. If the first call is in progress, the CIWF block sends an acknowledgment message to the home mobile switching center. The home mobile switching center then sends an acknowledgment message to the mobile communication device.

  When the mobile communication device receives the acknowledgment message, the mobile communication device stops the media streaming via the WiFi communication link and turns off the WiFi processing unit. Then, the CIWF block changes the registration of the mobile communication device in the WIWF block to the IP address of the CIWF block. The CIWF block sends to the WIWF block a re-invite message representing media switching from the IP address of the first wireless access point to the IP address of the CIWF block. The media streaming associated with the first call is then redirected to the CIWF block, and then the media is switched to the home mobile switching center. The media stream associated with the first call is associated with the second call, and the media stream is streamed from the VoIP network to the WIWF block, the CIWF block, the home mobile switching center, and the mobile communication device. Thereby, the transition in the second scenario is completed. Later, when the mobile communication device disconnects the second call, a corresponding call disconnection process is performed according to the instruction of the CIWF block. When the final destination device disconnects the second call, a corresponding call disconnection process is performed according to instructions from both the WIWF block and the CIWF block.

  The third scenario is that the mobile communication device initiates a call within the first WiFi communication range, sets up the back end of the call over the mobile network, and from the first WiFi communication range, the home mobile exchange of the mobile communication device This is a scenario of moving to a cell communication range supported by a station. In this scenario, the mobile communication device moves from the first WiFi communication range to a non-WiFi communication range. When the first call is initiated and set up, a WiFi communication link is established between the mobile communication device and the first wireless access point associated with the first WiFi coverage area. If the mobile communication device is within the first WiFi communication range, the mobile communication device registers with the home nomadic server via the first WiFi access point. The first call is routed from the wireless access point 40 via a mobile network, eg, a mobile switching center and a PLMN or PSTN.

  The mobile communication device monitors the signal strength or other criteria of the WiFi communication link. When the signal strength or other evaluation criteria falls below a predetermined threshold, the mobile communication device registers in this third scenario with the nearest mobile switching center that is the home mobile switching center of the mobile communication device. The mobile communication device also sends a call setup request to the home mobile switching center for the second call to the same final destination as the first call. The second call is set up by the home mobile switching center and routed to the CIWF block in the home nomadic server. The CIWF block determines from the WIWF block whether a first call is in progress. If the first call is in progress, the CIWF block sends an acknowledgment message to the home mobile switching center. The home mobile switching center then sends an acknowledgment message to the mobile communication device.

  When the mobile communication device receives the acknowledgment message, the mobile communication device stops the media streaming via the WiFi communication link and turns off the WiFi processing unit. Then, the CIWF block changes the registration of the mobile communication device in the WIWF block to the IP address of the CIWF block. The CIWF block sends a re-invite message to the WIWF block representing a media switch from the IP address of the first wireless access point to the IP address of the CIWF block. The media streaming associated with the first call is then redirected to the CIWF block, and then the media is switched to the home mobile switching center. The media stream associated with the first call is associated with the second call, and this media stream is provided from the mobile network to the CIWF block, the home mobile switching center, and the mobile communication device. Thereby, the transition in the third scenario is completed. Later, when the mobile communication device disconnects the second call, a corresponding call disconnection process is performed in accordance with an instruction from the CIWF block and the home mobile switching center. When the final destination device disconnects the second call, the corresponding call disconnect processing is performed according to the instruction of the CIWF block.

  The fourth scenario is that the mobile communication device initiates a call within the first WiFi communication range that is outside the cell communication range supported by the mobile mobile switching center of the mobile communication device, and the call backend through the VoIP network. This is a scenario for setting up and moving from the first WiFi communication range to the cell communication range supported by the visitor mobile switching center. In this scenario, the mobile communication device moves from the first WiFi communication range to a non-WiFi communication range. When the first call is initiated and set up, a WiFi communication link is established between the mobile communication device and the first wireless access point associated with the first WiFi coverage area. If the mobile communication device is within the first WiFi communication range, the mobile communication device registers with the home nomadic server via the first WiFi access point. In this way, the home nomadic server's WIWF block monitors the location of the mobile communication device. The first call is routed via the WiFi communication link from the mobile communication device to the first wireless access point, the visitor nomadic server WIWF block associated with the visitor mobile switching center, and the VoIP network.

  The mobile communication device monitors the signal strength or other criteria of the WiFi communication link. If the signal strength or other evaluation criteria falls below a predetermined threshold, the mobile communication device registers with the nearest mobile switching center that is the visitor mobile switching center of the mobile communication device in this fourth scenario. The mobile communication device notifies the WIWF block in the home nomadic server that the signal strength or other evaluation criteria has fallen below a predetermined threshold. The mobile communication device also transmits a call setup request to the visitor mobile switching center for the second call to the same final destination as the first call. The visitor mobile switching center sends a call setup request to the CIWF block in the visitor nomadic server. Within the visitor nomadic server, the CIWF block determines from the WIWF block whether a first call is in progress. Since the mobile communication device registers itself with the home nomadic server, not the visitor nomadic server, the WIWF block in the visitor nomadic server does not have an ongoing first call registration. In response, the visitor nomadic server sets up a second call over the mobile network. At the same time, the home nomadic server cancels the first call over the VoIP network.

  The fourth scenario is that the mobile communication device initiates a call within the first WiFi communication range that is outside the cell communication range supported by the mobile mobile switching center of the mobile communication device, and the back end of the call through the mobile network. This is a scenario for setting up and moving from the first WiFi communication range to the cell communication range supported by the visitor mobile switching center. In this scenario, the mobile communication device moves from the first WiFi communication range to a non-WiFi communication range. When the first call is initiated and set up, a WiFi communication link is established between the mobile communication device and the first wireless access point associated with the first WiFi access point. The first call is routed from the mobile communication device via the WiFi communication link to the first wireless access point, the visitor nomadic server CIWF block, the visitor mobile switching center, and the mobile network.

  The mobile communication device monitors the signal strength or other criteria of the WiFi communication link. When the signal strength or other evaluation criteria falls below a predetermined threshold, the mobile communication device registers with the nearest mobile switching center that is the visitor mobile switching center of the mobile communication device in this fifth scenario. If the mobile communication device is within the first WiFi communication range, the mobile communication device registers with the home nomadic server via the first WiFi access point. In this way, the home nomadic server's WIWF block monitors the location of the mobile communication device. The mobile communication device notifies the WIWF block in the home nomadic server that the signal strength or other evaluation criteria has fallen below a predetermined threshold. The mobile communication device also transmits a call setup request to the visitor mobile switching center for the second call to the same final destination as the first call. The visitor mobile switching center sends a call setup request to the CIWF block in the visitor nomadic server. Within the visitor nomadic server, the CIWF block determines from the WIWF block whether a first call is in progress. Since the mobile communication device registers itself with the home nomadic server, not the visitor nomadic server, the WIWF block in the visitor nomadic server does not have an ongoing first call registration. In response, the visitor's nomadic server sets up a second call over the mobile network. At the same time, the home nomadic server aborts the first call over the mobile network and the first WiFi communication link.

  Note that the five scenarios described above are not exclusive or comprehensive with respect to all scenarios, and the mobile communication device can move from the first communication range to the second communication range with the support of the nomadic server. Other scenarios can also be envisaged.

  Also, in some embodiments, the nomadic server 80 can communicate with other nomadic servers over the Internet and route and perform calls using VoIP. This server-server communication can be used for all calls including mobile-mobile. In such a situation, the mobile telephone communication is transmitted from the calling mobile telephone to the appropriate base station. From this base station, communication is routed to an appropriate nomadic server 80, which in some embodiments is the nomadic server 80 closest to the receiving base station 10. The calling-side nomadic server 80 transmits the communication to the nomadic server 80 closest to the appropriate base station 10 corresponding to the position of the called-side mobile phone via the Internet. The receiving-side nomadic server 80 transmits communication to the receiving-side base station 10, and the receiving-side base station 10 transmits communication to the called-side mobile phone. Thus, the only parts that are communicated via the mobile phone network are the first leg from the starting mobile phone to the appropriate base station and the last leg from the appropriate base station to the called mobile phone. . The remaining intermediate part is communicated over the Internet between the appropriate nomadic servers, which makes the call more efficient compared to traditionally communicating the call only over the mobile network. Communication is realized. Note that with this approach, communication takes place in both directions, the call is performed between the calling and called parties, and the first and last legs of the communication are routed through the mobile network. Those skilled in the art will appreciate that the remaining intermediate portion is routed between the nomadic servers 80 via the Internet 50.

  The present invention has been described in terms of specific embodiments, including various details, in order to provide a clear explanation of the structure and operating principles of the invention. Such specific embodiments and details thereof are not intended to limit the scope of the claims appended hereto. It will be apparent to those skilled in the art that the exemplary embodiments selected can be modified without departing from the spirit and scope of the invention.

1 illustrates an exemplary system of an interconnection network in which a nomadic server is connected to a mobile network, a wireless IP network, and a public telephone network. FIG. 2 is a simplified high-level block diagram of one embodiment of a mobile communication device.

Claims (38)

In a communication method for realizing communication for a mobile communication device moving between a plurality of different types of wireless networks,
a. Establishing a first communication link between the mobile communication device and a final destination device, including a first wireless communication link between the mobile communication device and a first type of wireless network; ,
b. Monitoring the signal strength of the first wireless communication link;
c. Establishing a second communication link between the interface server and the final destination device if the signal strength is below a predetermined threshold;
d. Notifying the mobile communication device that communication via the first communication link is terminated;
e. Establishing a second wireless communication link between the mobile communication device and a second type of wireless network by redirecting the second communication link from the interface server to the mobile communication device; A communication method.   The communication method according to claim 1, wherein the first type of wireless communication link includes a WiFi communication link, and the first type of wireless network includes a WiFi network access point.   The communication method according to claim 2, wherein the second type of wireless network includes a wireless mobile network.   The communication method according to claim 1, wherein the establishment of the first communication link includes routing via a VoIP network.   2. The communication method according to claim 1, wherein the establishment of the first communication link includes routing through a mobile network.   The communication method according to claim 1, wherein the establishment of the second communication link includes routing via a VoIP network.   2. The communication method according to claim 1, wherein the establishment of the second communication link includes routing through a mobile network.   The mobile communication device further comprises a step of providing information indicating a connection state from the mobile communication device to the interface server when the mobile communication device is within a first communication range of the first type wireless network. Communication method.   9. The communication method according to claim 8, further comprising: providing routing association information for associating the mobile communication device with an interface server to a mobile switching center in the second type of wireless network.   When the connection state becomes valid, based on the routing association information, terminal communication information destined for the mobile communication device is routed from the mobile switching center to the interface server, via the first type wireless network. The communication method according to claim 9, further comprising the step of routing the termination communication information from the interface server to the mobile communication device.   The communication method according to claim 10, further comprising the step of deleting the routing association information from the mobile switching center when the connection state is not provided to the interface server.   The communication method according to claim 1, further comprising the step of registering the mobile communication device with a mobile switching center in the second type of wireless network when the signal strength falls below a predetermined threshold.   13. The communication method according to claim 12, further comprising the step of setting up a second communication link with a final destination device and transmitting information relating to the second communication link to the interface server. In a communication method for realizing communication for a mobile communication device moving between a plurality of WiFi communication ranges,
a. Associating the mobile communication device with a nomadic server connected to one or more WiFi access points;
b. Establishing a first WiFi communication link between the mobile communication device and a first WiFi access point;
c. Supplying the IP address of the first WiFi access point to the nomadic server and registering the mobile communication device in the nomadic server;
d. Configuring a communication path to the mobile communication device via the nomadic server based on the IP address of the first WiFi access point and the first WiFi communication link;
e. Detecting movement of the mobile communication device to the communication range of the second WiFi access point;
f. Registering the mobile communication device with a nomadic server including the IP address of the second WiFi access point;
g. Establishing a second WiFi communication link between the mobile communication device and a second WiFi access point;
h. Reconfiguring a communication path based on the IP address of the second WiFi access point and the second WiFi communication link.   The communication method according to claim 14, further comprising the step of associating the mobile communication device with the nomadic server in the mobile switching center.   The communication method according to claim 14, further comprising providing routing association information for associating the mobile communication device with an interface server to a mobile switching center in a mobile network.   Based on the routing association information, the mobile switching center routes termination communication information destined for the mobile communication device to the interface server, and the termination communication from the interface server to the mobile communication device via the communication path. The communication method according to claim 16, further comprising the step of routing information.   Registering the mobile communication device with the nomadic server includes providing a connection state of the mobile communication device while the mobile communication device is within a specific communication range of a specific WiFi access point. The communication method according to claim 14. In a communication system for realizing communication for a mobile communication device moving between a plurality of different types of wireless networks,
a. Several different types of wireless networks,
b. A mobile communication device configured to access the plurality of wireless networks;
c. The mobile communication device is connected to the plurality of wireless networks, and the mobile communication device moves from a first wireless communication range related to the first type of wireless network to a second wireless communication range related to the second type of wireless network. A seamless communication link is maintained between the mobile communication device and the final destination device, and a first link between the mobile communication device and the final destination device via the first type of wireless network is maintained. While one communication link is active, it is set up to be transmitted to the interface server first via the second type of wireless network, and when the first communication link ends, the mobile communication device A communication system comprising: an interface server for establishing a second communication link to be routed.   20. The communication system according to claim 19, wherein the first communication link includes a first wireless communication link between the mobile communication device and a first type of wireless network.   21. The first wireless communication range includes a WiFi communication range, and the first wireless communication link includes a WiFi communication link between the mobile communication device and a WiFi access point. Communication system.   21. The communication system according to claim 20, wherein the first communication link includes a routing path through a VoIP network.   21. A communication system according to claim 20, wherein the first communication link includes a routing path through a mobile network.   20. The communication system according to claim 19, wherein the second communication link includes a second wireless communication link between the mobile communication device and the second type of wireless network.   25. The second wireless communication range includes a cell communication range, and the second wireless communication link includes a wireless mobile communication link between the mobile communication device and a base station. The communication system described.   25. The communication system of claim 24, wherein the second communication link includes a routing path through a VoIP network.   25. The communication system of claim 24, wherein the second communication link includes a routing path through a mobile network.   20. The communication system according to claim 19, wherein the second type of wireless network includes a wireless mobile network.   When the mobile communication device moves from the first wireless communication range associated with the first type of wireless network to the second wireless communication range associated with the second type of wireless network, the mobile communication device and the final While maintaining a seamless communication link with the destination device, while the first communication link between the mobile communication device and the final destination device via the first type of wireless network is valid Is set up to be transmitted to the interface server first via a second type of wireless network, and when the first communication link is terminated, establishes a second communication link routed to the mobile communication device Interface server   30. The interface server of claim 29, further comprising a first inter-network functional block that maintains current configuration and state information associated with the first communication link.   31. The first wireless communication range includes a WiFi communication range, and the first communication link includes a WiFi communication link between the mobile communication device and a WiFi access point. Interface server.   31. The interface server of claim 30, further comprising a second inter-network functional block that maintains current configuration and state information associated with the second communication link.   The interface server according to claim 32, further comprising a provisioning server for supplying setting information to the mobile communication device.   30. The interface server according to claim 29, wherein the interface server communicates with the mobile communication device via a mobile switching center.   The interface server according to claim 34, wherein the interface server is firmly connected to the mobile switching center via a network.   The interface server according to claim 34, wherein the interface server is loosely connected to the mobile switching center via a trunk interface or a soft switch.   The interface server according to claim 34, wherein the interface server communicates with the mobile switching center via an interface protocol established by the mobile switching center. In a communication method for realizing communication between mobile communication devices,
a. Routing communication addressed to the second communication device from the first mobile communication device via a first communication link between the first mobile communication device and the first base station;
b. Routing the communication via a second communication link between the first base station and a first control device;
c. Routing the communication via a third communication link including an Internet protocol network between the first control device and the second control device;
d. Routing the communication via a fourth communication link between the second control device and a second base station;
e. Routing the communication via a fifth communication link between the second base station and the second communication device.

Images