Abstract:
The present invention discloses a Softswitch and system for implementing the intelligent network in the next generation networks and a method for interconnecting the intelligent networks to the PSTN. The Softswitch comprises: a network adaptive device for implementing the communication between the Softswitch and other devices in said network, as well as receiving the call request; a call server for determining whether the call received by said network adaptive device is a common call or the call of the intelligent network and processing the common call; and an INAP adapter for responding the call of the intelligent network and encoding/decoding the INAP message.

Description:
TECHNICAL FIELD  
       [0001]     The present invention relates to intelligent network (IN), in particular, to the implementation of an intelligent network in the next generation networks (NGN) and its interconnection to the traditional PSTN (Public Switched Telephone Network)  
       TECHNICAL BACKGROUND  
       [0002]     Due to overlaying intelligent networks over common-used circuit switching networks, not only can we make common calls, but also we can get other intelligent services through dialing different Service Access Code. At present, widely-used intelligent network services include, such as, Freephone, Account card calling (ACC), Virtual private network (VPN), Universal Personal Telecommunication (UPT), Wide Area Centrex (WAC), Televoting (VOT) and Mass Calling (MAS) Service and so on.  
         [0003]     U.S. Pat. Nos. 5,479,495 (Method and system for automatically accessing and invoking switch-based services in an advanced intelligent network) and 5,553,130 (Number translation services matrix) disclose the ways for implementing PSTN-based services of providing SCP, their contents are incorporated herein by reference.  
         [0004]     In the next generation communication networks, there will be much more intelligent service providers providing services, so it is necessary to continue such intelligent network services in the next generation networks. On the other hand, traditional intelligent network services can not be replaced at one night, as a result, the following requirements arise: the users of the traditional PSTN network want to access intelligent networks in the next generation networks and the users in the next generation networks want to access the intelligent services in the traditional PSTN networks. In other words, there is a need of interconnection of intelligent network services between PSTN networks and the next generation networks.  
         [0005]     However, because of the essential differences in structures, principles and standards between traditional PSTN networks and the next generation networks, it is very difficult to realize the requirements mentioned above.  
       SUMMARY OF THE INVENTION  
       [0006]     According to one aspect of the present invention, there is provided a Softswitch for a next generation network, characterized in that said Softswitch includes: a network adaptive device for implementing the communication between the Softswitch and other devices in said network, as well as receiving the call request; a call server for determining whether the call received by said network adaptive device is a common call or a call of the intelligent network and processing the common call; and an INAP adapter for responding the call of the intelligent network and encoding/decoding the INAP message.  
         [0007]     According to another aspect of the present invention, there is provided a system for implementing an intelligent network, including: a Softswitch, said system further includes at least one SCP for executing intelligent service logics and producing INAP messages; and an IP network for connecting said Softswitch and the SCP; herein, said Softswitch includes: a network adaptive device for implementing the communication between the Softswitch and other devices in said network, as well as receiving the call request; a call server for determining whether the call received by said network adaptive device is a common call or a call of the intelligent network and processing the common call; and an INAP adapter for responding the call of the intelligent network and encoding/decoding the INAP message.  
         [0008]     According to still another aspect of the present invention, there is provided a method for a PSTN telephone to access into an intelligent network service in a next generation network, herein there is at least one SCP in said next generation network for executing the intelligent service logics, said method includes: issuing a call request from said PSTN telephone through dialing an accessing code; transforming said call request issued by the PSTN telephone into a protocol format suitable for the next generation network; determining whether said call request is an intelligent network service provided by the SCP or not; encoding said call request into an INAP message and transferring the message to said SCP, if said call request is an intelligent network service provided by the SCP; and responding said INAP message and processing said call request by said SCP.  
         [0009]     According to still another aspect of the present invention, there is provided a method for a telephone in a next generation network to access into an intelligent network service in a PSTN network, herein there is at least one SCP in said PSTN network for executing the intelligent service logics, said method includes: issuing a call request from said telephone in the next generation network through dialing an accessing code; determining whether said call request is an intelligent network service provided by the SCP or not; encoding said call request into an INAP message, if said call request is an intelligent network service provided by the SCP; transforming said INAP message into a format suitable for the PSTN network and transferring said INAP message to said SCP; and responding said INAP message and processing said call request by said SCP.  
         [0010]     According to still another aspect of the present invention, there is provided a method for a telephone in a next generation network to access into an intelligent network service in a PSTN network, herein there is at least one SCP in said PSTN network for executing the intelligent service logics, said method includes: issuing a call request from said telephone in the next generation network through dialing an accessing code; transforming said call request into a format suitable for the PSTN network and transferring it to the PSTN network; determining whether said call request is an intelligent network service provided by the SCP or not; encoding said call request into an INAP message, if said call request is an intelligent network service provided by the SCP; transferring said INAP message to said SCP; and responding said INAP message and processing said call request by said SCP. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     It is believed that the above and other advantages, objectives and features of the invention will become more apparent through the following description of the preferred embodiments of the present invention with reference to the drawings, in which,  
         [0012]      FIG. 1  is a diagram illustrating the implementation of interconnection of intelligent network services in PSTN and the next generation networks according to an embodiment of the present invention;  
         [0013]      FIG. 2  is a block diagram showing the Softswitch software layered architecture according to an embodiment of the present invention;  
         [0014]      FIG. 3  is a diagram illustrating the process for implementing intelligent network service of Account card calling in a NGN network by using the Softswitch according to an embodiment of the present invention;  
         [0015]      FIG. 4  is a flow chart showing a telephone in a PSTN network accessing intelligent services in a NGN network according to an embodiment of the present invention;  
         [0016]      FIG. 5  is a flowchart showing a telephone in a NGN network accessing intelligent services in a PSTN network according to an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0017]     Next, detailed description will be given to the preferred embodiments of the present invention with reference to the drawings.  
         [0018]      FIG. 1  is a diagram illustrating the implementation of interconnection of intelligent network services in PSTN and the next generation networks according to an embodiment of the present invention.  FIG. 1  shows PSTN/ISDN  100  and SS7 (Signaling System Number 7) network  101 . Those skilled in the art know that signalings are transmitted through public channel signaling protocol, i.e. SS7, in a data network independent of the audio/medium stream circuit network. In the present application, a network that includes a SS7 network and a PSTN/ISDN circuit switching network all together will be called a PSTN network.  
         [0019]     A traditional intelligent network is an architecture that realizes advanced intelligent functions. Existing ways for implementing an intelligent network usually include service switching point (SSP), such as central exchange or end office; service control point (SCP), for executing functional service logics, being the core of a intelligent network; intelligent peripheral (Ip), for providing special resources required by intelligent network services, such as prompting play operation, storing records, facsimiles or others; and other components, such as, service data point (SDP), service management point (SMP), service creation environment point (SCEP), attached device (AD) and so on.  
         [0020]     As shown in  FIG. 1 , intelligent network services are realized in the PSTN network, wherein at least one SCP  110  is included. Of course, in a real application environment, more SCPs and other components mentioned above may be included. For simplicity, here one SPC  110  is taken as an example.  
         [0021]     Besides,  FIG. 1  shows the core packet switched network  200  (next generation network, NGN), NGN network refers to a combined network with IP as the central service, which may also support audio, data and multimedia services. Because a PSTN network is based on circuit switching and a NGN network is based on IP packet switching, it is necessary to arrange all kinds of gateways between them so as to connect these two networks to realize interconnection of telephone service. These gateways mainly include two types: media gateway and signaling gateway. A media gateway is used for transferring media information ( such as audio and video) from one network side to another network side, the transfer gateway TG  122  and access gateway AG  123  in  FIG. 1  are examples of media gateways. A signaling gateway is used for transferring signaling information from one network side to another network side. Signaling gateway SG  121  in  FIG. 1  is an example of signaling gateways. In actual applications, there are gateways that combine functions of the signaling gateway and the media gateway, such as the network accessing server NAS  124 . Typically, NAS  124  may use SIP or H.323 to implement interconnection of telephone services on the PSTN network and the NGN network.  
         [0022]     In  FIG. 1 , there is Softswitch  201  and service control point SCP  202  connecting to the core packet switched network  200 . The Softswitch equipment, which is the core of the next generation network for calling and control, is used for providing call control and connection control functions to the services that have real time requirements in the next generation network. Based on the research on the existing Softswitch equipments, the present invention is to further implement intelligent services in next generation networks and interconnection of intelligent services between PSTN networks and next generation networks.  
         [0023]     Users of a next generation network may call telephone, intelligent network, video and other services through telephones and terminals  127 A- 127 N. Usually, these telephones and terminals  127 A- 127 N may be connected to the core packet switched network  200  through the comprehensive accessing device IAD  125 .  
         [0024]     According to one aspect of the present invention, there is provided an approach for implementing intelligent services in the next generation network. Next, detailed description will be given with reference to  FIG. 1  and  FIG. 2 .  FIG. 2  is a block diagram showing the Softswitch software layered architecture according to an embodiment of the present invention. As shown in  FIG. 2 , the Softswitch  300  includes: a network adaptive device  310 , a call server  320 , a resource manager  330 , an INAP (CAP, MAP) adapter  340  and an INAP (CAP, MAP)/TCP interface  350 .  
         [0025]     The network adaptive device  310  is located at the bottom layer of the function modules of the Softswitch, for supporting standard protocols in said network, completing bottom layer communications between the Softswitch and other devices on the network, receiving data in packets from the network  200 , including call requests from telephone users, and sending data from the modules of higher layers, with required format and address, to the network  200 .  
         [0026]     In the network adaptive device  310  of the Softswitch shown in  FIG. 2 , signaling transmitting adapter  312  and media gateway control adapter  313  are included. The signaling transmitting adapter is used for transferring signaling data through IP packets. For instance, according to SIGTRAN protocol or H.248 protocol, the signaling data are transferred to the signal gateway SG 121  and received from the signaling gateway SG 121 . Those skilled in the art know that SIGTRAN protocol and H.248 protocol have been designed for transmitting signaling information in IP networks. However, it should be noted that the present invention is not limited to using SIGTRAN protocol or H.248 protocol. Other protocols that can achieve the above-mentioned objectives may be used either.  
         [0027]     The media gateway control adapter  313  in the network adaptive equipment  310  is used for transmitting control information between the Softswitch and all kinds of media gateways in the network  200 , such as, transmitting control information, according to H.248 protocol, to and from the transfer gateway TG  122  and access gateway AG  123 , or transmitting control information, according to SIP or H.323 protocols, to and from the network accessing server NAS  124 . The present invention is not limited to using H.248, H.323, SIP or MGCP protocols for transferring control information, other protocols that can achieve the above-mentioned objectives may be used either.  
         [0028]     There are a call server  320  and a resource manager  330  in the higher layer of the network adaptive device  310 . The call server  320  is used to process the basic call, to complete the identification of the intelligent service and upward transmission of the data of the intelligent service, and to make response to some requests downward transmitted from the INAP (CAP, MAP) adapter  340 . The resource manager  330  is used to manage resources, managing resources, such as audio resources, and controlling related process. In the intelligent services, when SCP prompts a user to input interactive information, it is the resource manager  330  that controls the interaction between the user and the audio resource, and transmits the user input data to the INAP (CAP, MAP) adapter  340  at the higher layer.  
         [0029]     The INAP (CAP, MAP) adapter  340  is used to interpret an INAP massage, transfer the control information contained in the message to the call server  320  and the resource manager  330 , and encode the interaction information with the user into an INAP message and send the message to, such as, SCP  202  through a corresponding transmission protocol.  
         [0030]     Optionally, in the present embodiment, the Softswitch may further include an INAP(CAP, MAP)/TCP interface  350  for directly sending an INAP message produced by the INAP adapter through TCP/IP protocol and correspondingly receiving an INAP message directly transmitted from the network  200  by using TCP/IP.  
         [0031]     Thus, by using above-mentioned Softswitch as well as SCP  202 , media server  203  and others, it is possible to implement intelligent services in a next generation network. Next, taking the intelligent network counting card as an example, the process to implement an intelligent service will be described in an embodiment of the present invention.  FIG. 3  is a diagram illustrating the process for implementing intelligent network counting card service in the network  200  by using the Softswitch according to an embodiment of the present invention.  
         [0032]     Suppose that a telephone  127 A connected to network  200  through the IAD  125  has called an accessing code for the intelligent network Acounting Calling Card. First, the call is transmitted to the Softswitch  201 . After the Softswitch  201  completes reception of the accessing code, the call server  320  analyzes the called number and determines whether the call is an intelligent call. The call server  320  may complete the determination through searching a database (not shown) that stores the accessing codes of all intelligent services. When the call is determined as an intelligent call, the call server  320  will transmit the call to the INAP adapter. Then, the INAP (CAP, MAP) adapter  340  will produce an IDP message and send it to the SCP  202  by the signaling transmission adapter through SIGTRAN protocol. Alternatively, the message may be transmitted to the SCP  202  through INAP (CAP, MAP)/TCP interface  340 .  
         [0033]     Having received the IDP message, the SCP  202  executes corresponding service logics, producing CTR (connecting-to-resource message) instruction message and sending it to the Softswitch  201 . The Softswitch  201  receives the CTR instruction message and decodes the message with the INAP (CAP, MAP) adapter  340 , then the resource manager  330  and the call server  320  work together to connect the user&#39;s media stream with the resource of the media server  203 , and after having received the P&amp;C instruction message from SCP  202 , the resource manager  330  instructs the media server  203  to play prompt voice and collects the user-dialed number. The user-dialed number is encoded into a ResultReport response message by the INAP (CAP, MAP) adapter  340  and sent to the SCP  202 . Thus, after several interactions, the SCP  202 , through the Softswitch  201 , has collected the user&#39;s card number, secret key, called number and other information.  
         [0034]     Then, the SCP  202 , based on the service logic flow, sends a connect instruction to the Softswitch  201 , and after the INAP (CAP, MAP) adapter  340  of the Softswitch  201  has decoded the instruction message, the callee is connected. The call is established. When the caller or the callee hangs up, the INAP (CAP, MAP) adapter  340  of the Softswitch  201  produces a counting message, a BCSM event report and other messages, and sends them to the SCP  202 , then the call is finished.  
         [0035]     Besides, the present invention further provides a method for a PSTN telephone to access into an intelligent network service in a next generation network.  FIG. 4  is a flow chart showing a telephone in a PSTN network accessing intelligent services in a NGN network according to an embodiment of the present invention.  
         [0036]     As shown in  FIG. 4 , first at Step  401 , a PSTN telephone, such as the telephone  102 A, dials an accessing code and issues a call request. Then, at Step  405 , through a signaling gateway (such as the SG  121  in  FIG. 1 ) and a media gateway (such as the TG  122  in  FIG. 1 ), the call is outbound for the Softswitch  201  of the core packet network  200 . At Step  410 , the Softswitch  201  analyzes the call, determines whether the call is a call for an intelligent network service; if not, the call server  320  of the Softswitch  201  process the basic call at Step  415 , otherwise, at Step  420 , the INAP (CAP, MAP) adapter  340  of the Softswitch  201  produces an INAP message and sends it to the SCP  202 . Finally, at Step  425 , the SCP  202  executes service logics and processes the call request through interaction of the Softswitch  201  with the telephone  102 A.  
         [0037]     Furthermore, the present invention provides a method for a telephone in a next generation network to access into an intelligent network service in a PSTN network.  FIG. 5  is a flowchart showing a telephone in a NGN network accessing intelligent services in a PSTN network according to an embodiment of the present invention.  
         [0038]     As shown in  FIG. 5 , first at Step  501 , a NGN telephone, such as the telephone  127 A, dials an accessing code and issues a call request. The request is transmitted to the Softswitch  201 . Then, at Step  505 , the Softswitch  201  analyzes the call request, determines whether the call is a call for an intelligent network service; if not, the call server  320  of the Softswitch  201  process the basic call at Step  510 , otherwise, at Step  515 , the INAP (CAP, MAP) adapter  340  of the Softswitch  201  produces an INAP message. The produced INAP message is sent to the signaling gateway SG 121  with a SIGTRAN protocol format, and forwarded to the SCP  110  in the PSTN network  100  by the SG  121 . Finally, at Step  525 , the SCP  110  executes the intelligent network&#39;s service logics and processes the call request through interaction of the signaling gateway SG  121 , the media gateway TG  122  and the Softswitch  201  with the telephone  127 A.  
         [0039]     Alternately, according to another embodiment of the present invention, when the Softswitch  201  determines that the call request is an request for an intelligent network service provided by the SCP  110  of the PSTN network, the Softswitch  201  does not produce an INAP message, instead, the call request is outbound for the PSTN network  100  through the signaling gateway SG  121  and the media gateway TG  122 , and encoded/decoded by a SSN (not shown) in the PSTN network.  
         [0040]     Though the present invention has been described in details with some exemplary embodiments of the invention, these embodiments are not exhaustive. Those skilled in the art may make various variations and modifications within the spirit and scope of the present invention. Therefore, the present invention is not limited to these embodiments, rather, the scope of the present invention is only defined by the appended claims.