FORM 2
THE PATENTS ACT, 1970 (39 OF 1970) & THE PATENT RULES, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
“METHOD AND SYSTEM FOR IDENTIFYING SCSCF NODE ASSOCIATED
WITH ORIGINATING PARTY”
We, Jio Platforms Limited, an Indian National, of Office - 101, Saffron, Nr. Centre Point, Panchwati 5 Rasta, Ambawadi, Ahmedabad - 380006, Gujarat, India.
The following specification particularly describes the invention and the manner in which it is to be performed.

METHOD AND SYSTEM FOR IDENTIFYING SCSCF NODE ASSOCIATED
WITH ORIGINATING PARTY
FIELD OF THE DISCLOSURE
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[0001] The present disclosure relates generally to the field of wireless communication systems. More particularly, the present disclosure relates to methods and systems for identifying Serving - Call Session Control Function (SCSCF) node associated with originating party.
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BACKGROUND
[0002] The following description of related art is intended to provide background information pertaining to the field of the disclosure. This section may include certain 15 aspects of the art that may be related to various features of the present disclosure. However, it should be appreciated that this section be used only to enhance the understanding of the reader with respect to the present disclosure, and not as admissions of prior art.
[0003] Wireless communication technology has rapidly evolved over the past few 20 decades, with each generation bringing significant improvements and advancements. The first generation of wireless communication technology was based on analog technology and offered only voice services. However, with the advent of the second-generation (2G) technology, digital communication and data services became possible, and text messaging was introduced. The third generation (3G) technology marked the introduction of high-25 speed internet access, mobile video calling, and location-based services. The fourth-generation (4G) technology revolutionized wireless communication with faster data speeds, better network coverage, and improved security. Currently, the fifth-generation (5G) technology is being deployed, promising even faster data speeds, low latency, and the ability to connect multiple devices simultaneously. With each generation, wireless 30 communication technology has become more advanced, sophisticated, and capable of delivering more services to its users.
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[0004] Interrogating Call Session Control Function (I-CSCF) is responsible for onward routing of a Session Initiation Protocol (SIP) messages to the appropriate Serving Call Session Control Function (S-CSCF) for a given subscriber. This routing capability is utilized in specific scenarios only, such as during registration in order to assign or ascertain 5 the S-CSCF which should be used. Routing SIP requests arriving from other SIP networks is also a responsibility of the I-CSCF. The I-CSCF queries the HSS in order to discover the S-CSCF a particular subscriber has been assigned to or select a new SCSCF based on configured capabilities.
10 [0005] However, in the existing methods, a user cannot be charged for multiple data communication sessions initiated by special application server (AS). Also, legal implication of tracing back of call to originating party, i.e., the user that initiates a call, especially in case of multiple receiving parties, i.e., the users that receive the call initiated by the originating party, involved, was not possible to be identified.
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[0006] Thus, there exists an imperative need in the art to provide a method and a system for identifying Serving - Call Session Control Function (SCSCF) node associated with originating party, which the present disclosure aims to address.
20 OBJECTS OF THE DISCLOSURE
[0007] Some of the objects of the present disclosure, which at least one embodiment disclosed herein satisfies are listed herein below.
25 [0008] It is an object of the present disclosure to provide a system and a method for identifying Serving - Call Session Control Function (SCSCF) node associated with originating party.
[0009] It is another object of the present disclosure to provide a solution that where ICSCF 30 only interrogates a contact number associated with originating party and ignores a contact number associated with receiving party.
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[0010] It is yet another object of the present disclosure to provide a solution that removes the requirement of another charging system to be developed at special Application Server (AS).
5 [0011] It is yet another object of the present disclosure to provide a solution that fulfils the legal telecom requirement of tracing the origin of the call, especially when special AS is involved.
[0012] It is yet another object of the present disclosure to provide one-to-many data 10 communication session.
SUMMARY
[0013] This section is provided to introduce certain objects and aspects of the present 15 disclosure in a simplified form that are further described below in the detailed description. This summary is not intended to identify the key features or the scope of the claimed subject matter.
[0014] In order to achieve at least one of the objectives as mentioned above, one aspect of
20 the present disclosure relates to a method for identifying a serving call session control
function (SCSCF) node associated with originating party. The method comprises
identifying, at an interrogating call session control function (ICSCF) node associated with
a receiving party, by an identification unit, a special prefix, wherein the special prefix is
attached in a contact number of the receiving party by an application server (AS) connected
25 to the SCSCF node associated with the originating party, upon an initiation of a call from
the originating party to the receiving party. The method further comprises performing, at
the ICSCF node associated with the receiving party, by a selection unit, a SCSCF node
selection procedure for identifying the SCSCF node associated with the originating party,
based on the special prefix. The method further comprises identifying, at the ICSCF node
30 associated with the receiving party, by the identification unit, the SCSCF node associated
with the originating party based on the configuration of the ICSCF node.
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[0015] Further, according to an aspect of the disclosure, prior to the attaching, by the AS, the special prefix in the contact number of the receiving party, the method comprises receiving, by the SCSCF associated with the originating party from a user device, the call initiated by the user device.
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[0016] Further, according to an aspect of the disclosure, the method comprises initiating, by the AS connected to the SCSCF node associated with the originating party, the call to the receiving party.
10 [0017] Further, according to an aspect of the disclosure, the initiating, by the AS connected to the SCSF node associated with the originating party, the call to the receiving party, comprises sending, by the AS to the ICSCF node associated with the receiving party, a session initiation protocol (SIP) message, wherein the SIP message comprises the special prefix attached in the contact number of the receiving party.
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[0018] Another aspect of the present disclosure relates to a system for identifying a serving call session control function (SCSCF) node associated with an originating party. The system comprises an interrogating call session control function (ICSCF) node associated with a receiving party. The ICSCF node is configured to have an identification unit which
20 is configured to identify a special prefix, wherein the special prefix is attached in a contact number of the receiving party, by an application server (AS) connected to the SCSCF node associated with the originating party, upon an initiation of a call from the originating party to the receiving party. The ICSCF node is further configured to have a selection unit which is configured to perform a SCSCF node selection procedure for identification of the SCSCF
25 node associated with the originating party based on the special prefix. Further, the identification unit is configured to identify the SCSCF node associated with the originating party based on the configuration of the ICSCF node.
[0019] Yet another aspect of the present disclosure relates to a non-transitory computer 30 readable storage medium storing instruction for identifying a serving call session control function (SCSCF) node associated with originating party. The storage medium comprises executable code which, when executed by one or more units of a system implemented by an interrogating call session control function (ICSCF) node associated with a receiving
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party, that causes an identification unit to identify a special prefix, wherein the special prefix is attached in a contact number of the receiving party, by an application server (AS) connected to the SCSCF node associated with the originating party, upon an initiation of a call from the originating party to the receiving party. Further, the executable code when 5 executed, causes a selection unit to perform a SCSCF node selection procedure for identification of the SCSCF node associated with the originating party, based on the special prefix. Further, the executable code when executed, causes the identification unit to identify the SCSCF node associated with the originating party based on the configuration of the ICSCF node.
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BRIEF DESCRIPTION OF DRAWINGS
[0020] The accompanying drawings, which are incorporated herein, and constitute a part of this disclosure, illustrate exemplary embodiments of the disclosed methods and systems
15 in which like reference numerals refer to the same parts throughout the different drawings. Components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Some drawings may indicate the components using block diagrams and may not represent the internal circuitry of each component. It will be appreciated by those skilled in the art that disclosure of such
20 drawings includes disclosure of electrical components, electronic components or circuitry commonly used to implement such components.
[0021] FIG. 1A illustrates an exemplary block diagram representation of a 5th generation core (5GC) network architecture.
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[0022] FIG. 1B illustrates an exemplary block diagram of a system [100] for identifying SCSCF node associated with originating party, in accordance with exemplary embodiments of the present disclosure.
30 [0023] FIG. 2 illustrates an exemplary method [200] flow diagram indicating the process for identifying SCSCF node associated with originating party, in accordance with exemplary embodiments of the present disclosure.
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[0024] FIG. 3 illustrates an exemplary scenario process [300] for identification of the SCSCF node associated with an originating party, in accordance with exemplary embodiments of the present disclosure.
5 [0025] FIG. 4 illustrates an exemplary block diagram of a computing device upon which an embodiment of the present disclosure may be implemented, in accordance with exemplary embodiments of the present disclosure.
[0026] The foregoing shall be more apparent from the following more detailed description 10 of the disclosure.
DETAILED DESCRIPTION
[0027] In the following description, for the purposes of explanation, various specific 15 details are set forth in order to provide a thorough understanding of embodiments of the present disclosure. It will be apparent, however, that embodiments of the present disclosure may be practiced without these specific details. Several features described hereafter can each be used independently of one another or with any combination of other features. An individual feature may not address any of the problems discussed above or might address 20 only some of the problems discussed above. Some of the problems discussed above might not be fully addressed by any of the features described herein. Example embodiments of the present disclosure are described below, as illustrated in various drawings in which like reference numerals refer to the same parts throughout the different drawings.
25 [0028] The ensuing description provides exemplary embodiments only, and is not intended to limit the scope, applicability, or configuration of the disclosure. Rather, the ensuing description of the exemplary embodiments will provide those skilled in the art with an enabling description for implementing an exemplary embodiment. It should be understood that various changes may be made in the function and arrangement of elements
30 without departing from the spirit and scope of the disclosure as set forth.
[0029] It should be noted that the terms "mobile device", "user equipment", "user device", “communication device”, “device” and similar terms are used interchangeably for the
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purpose of describing the disclosure. These terms are not intended to limit the scope of the disclosure or imply any specific functionality or limitations on the described embodiments. The use of these terms is solely for convenience and clarity of description. The disclosure is not limited to any particular type of device or equipment, and it should be understood 5 that other equivalent terms or variations thereof may be used interchangeably without departing from the scope of the disclosure as defined herein.
[0030] Specific details are given in the following description to provide a thorough understanding of the embodiments. However, it will be understood by one of ordinary skill
10 in the art that the embodiments may be practiced without these specific details. For example, circuits, systems, networks, processes, and other components may be shown as components in block diagram form in order not to obscure the embodiments in unnecessary detail. In other instances, well-known circuits, processes, algorithms, structures, and techniques may be shown without unnecessary detail in order to avoid obscuring the
15 embodiments.
[0031] Also, it is noted that individual embodiments may be described as a process which is depicted as a flowchart, a flow diagram, a data flow diagram, a structure diagram, or a block diagram. Although a flowchart may describe the operations as a sequential process, 20 many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be re-arranged. A process is terminated when its operations are completed but could have additional steps not included in a figure.
[0032] The word “exemplary” and/or “demonstrative” is used herein to mean serving as 25 an example, instance, or illustration. For the avoidance of doubt, the subject matter disclosed herein is not limited by such examples. In addition, any aspect or design described herein as “exemplary” and/or “demonstrative” is not necessarily to be construed as preferred or advantageous over other aspects or designs, nor is it meant to preclude equivalent exemplary structures and techniques known to those of ordinary skill in the art. 30 Furthermore, to the extent that the terms “includes,” “has,” “contains,” and other similar words are used in either the detailed description or the claims, such terms are intended to be inclusive—in a manner similar to the term “comprising” as an open transition word— without precluding any additional or other elements.
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[0033] As used herein, an “electronic device”, or “portable electronic device”, or “user device” or “communication device” or “user equipment” or “device” refers to any electrical, electronic, electromechanical and computing device. The user device is capable 5 of receiving and/or transmitting one or parameters, performing function/s, communicating with other user devices and transmitting data to the other user devices. The user equipment may have a processor, a display, a memory, a battery and an input-means such as a hard keypad and/or a soft keypad. The user equipment may be capable of operating on any radio access technology including but not limited to IP-enabled communication, Zig Bee,
10 Bluetooth, Bluetooth Low Energy, Near Field Communication, Z-Wave, Wi-Fi, Wi-Fi direct, etc. For instance, the user equipment may include, but not limited to, a mobile phone, smartphone, virtual reality (VR) devices, augmented reality (AR) devices, laptop, a general-purpose computer, desktop, personal digital assistant, tablet computer, mainframe computer, or any other device as may be obvious to a person skilled in the art for
15 implementation of the features of the present disclosure.
[0034] Further, the user device may also comprise a “processor” or “processing unit” includes processing unit, wherein processor refers to any logic circuitry for processing instructions. The processor may be a general-purpose processor, a special purpose
20 processor, a conventional processor, a digital signal processor, a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits, Field Programmable Gate Array circuits, any other type of integrated circuits, etc. The processor may perform signal coding data processing, input/output processing, and/or any other functionality that enables
25 the working of the system according to the present disclosure. More specifically, the processor is a hardware processor.
[0035] As portable electronic devices and wireless technologies continue to improve and grow in popularity, the advancing wireless technologies for data transfer are also expected 30 to evolve and replace the older generations of technologies. In the field of wireless data communications, the dynamic advancement of various generations of cellular technology are also seen. The development, in this respect, has been incremental in the order of second
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generation (2G), third generation (3G), fourth generation (4G), and now fifth generation (5G), and more such generations are expected to continue in the forthcoming time.
[0036] Radio Access Technology (RAT) refers to the technology used by mobile devices/ 5 user equipment (UE) to connect to a cellular network. It refers to the specific protocol and standards that govern the way devices communicate with base stations, which are responsible for providing the wireless connection. Further, each RAT has its own set of protocols and standards for communication, which define the frequency bands, modulation techniques, and other parameters used for transmitting and receiving data. Examples of
10 RATs include GSM (Global System for Mobile Communications), CDMA (Code Division Multiple Access), UMTS (Universal Mobile Telecommunications System), LTE (Long-Term Evolution), and 5G. The choice of RAT depends on a variety of factors, including the network infrastructure, the available spectrum, and the mobile device's/device's capabilities. Mobile devices often support multiple RATs, allowing them to connect to
15 different types of networks and provide optimal performance based on the available network resources.
[0037] An Interrogating Call Session Control Function (I-CSCF) refers to the control function that is responsible for onward routing of SIP messages to the appropriate Serving
20 Call Session Control Function (S-CSCF) for a given subscriber. This routing capability is utilized in specific scenarios only, such as during registration in order to assign or ascertain the S-CSCF which should be used. Routing a Session Initiation Protocol (SIP) request arriving from other SIP networks is also a responsibility of the I-CSCF. The I-CSCF queries the HSS in order to discover the S-CSCF a particular subscriber has been assigned to, or
25 select a new SCSCF based on configured capabilities.
[0038] A Serving Call Session Control Function (S-CSCF) is the primary node in the IMS responsible for session control. Subscribers will be allocated a S-CSCF for the duration of their IMS registration in order to facilitate routing of SIP messages as part of service 30 establishment procedures. Consequently, the S-CSCF will download a subscriber profile from the HSS (Home Subscriber Server) at the time of registration, which allows the S-CSCF to ascertain which Application Server (AS) any service requests should be sent to.
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[0039] The Application Server (AS) here, refers to a network component in the communication network which is responsible for hosting and delivering value-added services to subscribers by providing various personalized communication and multimedia services beyond basic voice calls and messaging in IP Multimedia System (IMS) network 5 environment thereby enhancing the overall user experience by offering a diverse range of advanced communication capabilities. For example, if a subscriber is allocated a SCSCF (S-CSCF) session, the S-CSCF retrieves the subscriber profile from its Home Subscriber Server (HSS). This profile includes information about which Application Server (AS) should handle service requests for that subscriber. When a subscriber initiates a service 10 request, the S-CSCF routes the request to the appropriate Application Server (AS) based on the subscriber's profile obtained from the HSS. When a subscriber initiates a service request, such as placing a video call or accessing voicemail, the S-CSCF routes the request to the appropriate Application Server (AS) based on the subscriber's profile obtained from the HSS.
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[0040] The Session Initiation Protocol (SIP) serves as a fundamental pillar in modern communication infrastructure, facilitating the initiation, management, and cessation of diverse communication sessions encompassing voice, video, and messaging applications. Widely adopted in Internet telephony, private IP telephone systems, and mobile phone 20 calling over LTE (VoLTE), SIP provides a standardized framework for establishing connections between endpoints across the network. By enabling seamless interaction between devices and services, SIP plays a pivotal role in ensuring the interoperability and reliability of contemporary communication systems, empowering users to engage in fluid, multimedia-rich interactions regardless of their preferred platform or device.
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[0041] As discussed in the background section, the current known solutions have several shortcomings such as: a user cannot be charged for multiple data communication sessions initiated by special application server (AS); and legal implication of tracing back of call to originating party, especially in case of multiple receiving parties involved, is not possible. 30 Here, the originating party refers to the party which makes / tries to establish a connection. For e.g. party A calls party B, where A signifies calling party/ originating party while B represents receiving party/ terminating party.
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[0042] The present disclosure aims to overcome the above-mentioned and other existing problems in this field of technology by selection of originating party network at an ICSCF. According to present solution, the I-CSCF is able to select a SCSCF based on the originating user by identifying a prefix in receiving party’s contact number. When said 5 prefix is identified by the ICSCF, the ICSCF calls a function to interrogate the originating party SCSCF to know the location of the originating party, instead of interrogating the home subscriber server (HSS) of the receiving party to know the SCSCF of the receiving party.
10 [0043] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings.
[0044] Referring to Fig. 1A an exemplary block diagram representation of 5th generation core (5GC) network architecture, in accordance with exemplary embodiment of the present
15 disclosure. As shown in Figure 1A, the 5GC network architecture [100A] includes a user equipment (UE) [102u], a radio access network (RAN) [104r], an access and mobility management function (AMF) [106a], a Session Management Function (SMF) [108s], a Service Communication Proxy (SCP) [110s], an Authentication Server Function (AUSF) [112a], a Network Slice Specific Authentication and Authorization Function (NSSAAF)
20 [114n], a Network Slice Selection Function (NSSF) [116n], a Network Exposure Function (NEF) [118n], a Network Repository Function (NRF) [120n], a Policy Control Function (PCF) [122p], a Unified Data Management (UDM) [124u], an application function (AF) [126a], a User Plane Function (UPF) [128u], a data network (DN) [130d], wherein all the components are assumed to be connected to each other in a manner as obvious to the person
25 skilled in the art for implementing features of the present disclosure.
[0045] The User Equipment (UE) [102u] interfaces with the network via the Radio Access Network (RAN) [104r]; the Access and Mobility Management Function (AMF) [106a] manages connectivity and mobility, while the Session Management Function (SMF) 30 [108s] administers session control; the service communication proxy (SCP) [110s] routes and manages communication between network services, enhancing efficiency and security, and the Authentication Server Function (AUSF) [112a] handles user authentication; the Network Slice Specific Authentication and Authorization Function (NSSAAF) [114n] for
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integrating the 5G core network with existing 4G LTE networks i.e., to enable Non-Standalone (NSA) 5G deployments, the Network Slice Selection Function (NSSF) [116n], Network Exposure Function (NEF) [118n], and Network Repository Function (NRF) [120n] enable network customization, secure interfacing with external applications, and 5 maintain network function registries respectively; the Policy Control Function (PCF) [122p] develops operational policies, and the Unified Data Management (UDM) [124u] manages subscriber data; the Application Function (AF) [126a] enables application interaction, the User Plane Function (UPF) [128u] processes and forwards user data, and the Data Network (DN) [130d] connects to external internet resources; collectively, these 10 components are designed to enhance mobile broadband, ensure low-latency communication, and support massive machine-type communication, solidifying the 5GC as the infrastructure for next-generation mobile networks.
[0046] Radio Access Network (RAN) [104r] is the part of a mobile telecommunications 15 system that connects user equipment (UE) [102u] to the core network (CN) and provides access to different types of networks (e.g., 5G network). It consists of radio base stations and the radio access technologies that enable wireless communication.
[0047] Access and Mobility Management Function (AMF) [106a] is a 5G core network
20 function responsible for managing access and mobility aspects, such as UE registration, connection, and reachability. It also handles mobility management procedures like handovers and paging.
[0048] Session Management Function (SMF) [108s] is a 5G core network function
25 responsible for managing session-related aspects, such as establishing, modifying, and releasing sessions. It coordinates with the User Plane Function (UPF) [128u] for data forwarding and handles IP address allocation and QoS enforcement.
[0049] Service Communication Proxy (SCP) [110s] is a network function in the 5G core
30 network that facilitates communication between other network functions by providing a secure and efficient messaging service. It acts as a mediator for service-based interfaces.
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[0050] Authentication Server Function (AUSF) [112a] is a network function in the 5G
core responsible for authenticating UEs during registration and providing security services. It generates and verifies authentication vectors and tokens.
5 [0051] Network Slice Specific Authentication and Authorization Function (NSSAAF)
[114n] is a network function that provides authentication and authorization services specific to network slices. It ensures that UEs can access only the slices for which they are authorized.
10 [0052] Network Slice Selection Function (NSSF) [116n] is a network function
responsible for selecting the appropriate network slice for a UE based on factors such as subscription, requested services, and network policies.
[0053] Network Exposure Function (NEF) [118n] is a network function that exposes
15 capabilities and services of the 5G network to external applications, enabling integration with third-party services and applications.
[0054] Network Repository Function (NRF) [120n] is a network function that acts as a
central repository for information about available network functions and services. It 20 facilitates the discovery and dynamic registration of network functions.
[0055] Policy Control Function (PCF) [122p] is a network function responsible for
policy control decisions, such as QoS, charging, and access control, based on subscriber information and network policies.
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[0056] Unified Data Management (UDM) [124u] is a network function that centralizes
the management of subscriber data, including authentication, authorization, and subscription information.
30 [0057] Application Function (AF) [126a] is a network function that represents external applications interfacing with the 5G core network to access network capabilities and services.
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[0058] User Plane Function (UPF) [128u] is a network function responsible for handling user data traffic, including packet routing, forwarding, and QoS enforcement.
[0059] Data Network (DN) [130d] refers to a network that provides data services to user 5 equipment (UE) in a telecommunications system. The data services may include but are not limited to Internet services, private data network related services.
[0060] Referring to Fig. 1B, an exemplary block diagram of a system [100] for identifying a serving call session control function (SCSCF) node [108] associated with an originating
10 party is shown, in accordance with the exemplary embodiments of the present disclosure. The system [100] comprises at least application server (AS) [104] connected to the SCSCF node [108] associated with the originating party, and at least one interrogating call session control function (ICSCF) node [106] associated with the receiving party. Further, the ICSCF node [106] comprises at least one identification unit [107] and at least one selection
15 unit [109]. Also, all of the components/ units of the system [100] are assumed to be connected to each other unless otherwise indicated below. Also, in Fig. 1B only a few units are shown, however, the system [100] may comprise multiple such units or the system [100] may comprise any such numbers of said units, as required to implement the features of the present disclosure. Further, in an implementation, the system [100] may reside in a
20 server or a network entity. In yet another implementation, the system [100] may reside partly in the server/ network entity and partly in the user device.
[0061] The system [100] is configured for receiving data communication from the SCSCF node [108] based on a contact number associated with the originating party, with the help 25 of the interconnection between the components/units of the system [100].
[0062] Further, the identification unit [107] of the ICSCF node [106] is configured to identify a special prefix. It is important to note that the special prefix is attached in a contact number of the receiving party by an application server (AS) [104] connected to the SCSCF 30 node [108] associated with the originating party upon an initiation of a call from the originating party to the receiving party. The present disclosure further encompasses that prior to the AS [104] attaching the special prefix in the contact number of the receiving party, the SCSCF [108] associated with the originating party is configured to receive the
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call initiated by the user device. The present disclosure further encompasses the AS [104] being connected to the SCSCF node [108] associated with the originating party is further configured to initiate the call to the receiving party. The present disclosure also encompasses that the AS [104] the SCSCF node [108] associated with the originating party, 5 for initiating the call to the receiving party, is further configured to send a session initiation protocol (SIP) message to the ICSCF node [106] associated with the receiving party. It is to be noted that the SIP message comprises the special prefix attached in the contact number of the receiving party.
10 [0063] Further, the selection unit [109] connected to at least the identification unit [107] is configured to perform, a SCSCF node selection procedure for identification the SCSCF node [108] associated with the originating party based on the special prefix. In general, the SCSCF node [108] is a key element in IP Multimedia Subsystem (IMS) networks that is responsible for call control, handling registration, session establishment, and termination
15 for multimedia services like voice over IP (VoIP) and video calls.
[0064] Further, the identification unit [107] is further configured to identify, the SCSCF node [108] associated with the originating party based on the configuration of the ICSCF node [106].
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[0065] Yet another aspect of the present disclosure relates to a non-transitory computer readable storage medium storing instruction for identifying a serving call session control function (SCSCF) node [108] associated with an originating party. The storage medium comprises executable code which, when executed by one or more units of a system [100]
25 implemented by an interrogating call session control function (ICSCF) node [106] associated with a receiving party, that may causes an identification unit [107], the identification unit [107] being configured to identify, a special prefix, wherein the special prefix is attached in a contact number of the receiving party, by an application server (AS) [104] connected to the SCSCF node [108] associated with the originating party, upon an
30 initiation of a call from the originating party to the receiving party, and a selection unit [109] connected to at least the identification unit [107, wherein the selection unit [109] being configured to perform, a SCSCF node selection procedure for identification of the SCSCF node [108] associated with the originating party based on the special prefix, and
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wherein the identification unit [107] is further configured to identify, the SCSCF node [108] associated with the originating party based on the configuration of the ICSCF node [106].
5 [0066] Referring to Fig. 2, an exemplary method [200] flow diagram indicating the process for selecting a serving call session control function (SCSCF) node [108] associated with an originating party, in accordance with exemplary embodiments of the present disclosure is shown. In an implementation the method [200] is performed by a system [100]. As shown in Figure 2, the method [200] starts at step [202].
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[0067] At step [204], the method [200] as disclosed by the present disclosure comprises identifying, at an interrogating call session control function (ICSCF) node [106] associated with a receiving party, by an identification unit [107], a special prefix, wherein the special prefix is attached in a contact number of the receiving party, by an application server (AS)
15 [104] connected to the SCSCF node [108] associated with the originating party, upon an initiation of a call from the originating party to the receiving party. Further, as disclosed by the present disclosure, prior to the attaching, by the AS [104], the special prefix in the contact number of the receiving party, the method [200] comprising receiving, by the SCSCF [108] associated with the originating party from a user device, the call initiated by
20 the user device.
[0068] Next, at step [206], the method [200] as disclosed by the present disclosure comprises performing, a SCSCF node selection procedure for identifying the SCSCF node [108] associated with the originating party by a selection unit [109] at the ICSCF node 25 [106] associated with the receiving party based on the special prefix. It is to be noted that the SCSCF node selection procedure may include but not limited to querying the location of the party with the HSS server for information of the SCSCF node [108] by the ICSCF node [106] for selection.
30 [0069] Next, at step [208], the method [200] as disclosed by the present disclosure comprises identifying, the SCSCF node [108] associated with the originating party at the ICSCF node [106] associated with the receiving party based on the configuration of the ICSCF node [106] by the identification unit [107] at the ICSCF node [106] associated with
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the receiving party. It is to be noted that the identification of the SCSCF node [108] is done upon receiving the information of the SCSCF node [108] by the ICSCF node [106]. This identification is done based on the local governing policies of the network and the information of the selected SCSCF node [108].
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[0070] Further, as disclosed by the present disclosure, upon successful identifying the SCSF node [108] associated with the originating party at the ICSCF node [106] based on the configuration of the ICSCF node [106] by the identification unit [107], the method [200] further comprises initiating, by the AS [104] connected to the SCSCF node [108] 10 associated with the originating party, the call to the receiving party. Furthermore, in order to initiate the call to the receiving party, the method [200] further discloses sending, by the AS [104] to the ICSCF node [106] associated with the receiving party, a session initiation protocol (SIP) message, wherein the SIP message comprises the special prefix attached in the contact number of the receiving party.
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[0071] Thereafter, the method terminates at step [210].
[0072] Referring to the Fig. 3, illustrates an exemplary scenario process [300] for identification of a serving call session control function (SCSCF) node [308] associated with
20 an originating party is shown, in accordance with exemplary embodiments of the present disclosure. When a user (from the originating party/ calling party i.e., A-party) makes call to a user (from a receiving party i.e., B-party), the call is made to the SCSCF [308] at the originating party i.e., A-party end. In the exemplary scenario, the ICSCF [106] of FIG. 1B is represented by ICSCF [306] in Fig. 3. The SCSCF [308] connects with ICSCF [306] of
25 the receiving party/ B-party end. For this purpose, an application server (AS) [304] (or the special application server) is connected to the SCSCF [308]. The AS [304] is responsible for providing/ hosting different types of services. For each different type of service, the AS [304] selects a different interrogating call session control function (ICSCF) [306]. The AS [304] sends session initiation protocol (SIP) message to the interrogating call session
30 control function (ICSCF) [306] on behalf of the originating party i.e., A-party. It is important to note that the SIP message comprises a special prefix attached in a contact number of the receiving party. The AS [304] originates call for participants on behalf of the calling party by appending this special prefix in the participant number (i.e., B-party).
18

For e.g., during the call, requests are sent which are represented by B1, B2 and B3. This special prefix is used at the ICSCF [306], which will identify special handling required for SCSCF selection of the originating party i.e., A-party. Therefore, the ICSCSF [306] selects the same SCSCF [308] using the same prefix. Thus, the ICSCF [306] is able to select the 5 SCSCF [308] based on the originating user by identifying prefix in the contact number of the receiving party i.e., B-party contact number. For e.g. these selections are denoted by A-B1, A-B2 and A-B3. This special prefix is used at the ICSCF [306] which is responsible for identifying and performing special function of selecting the SCSCF [308] of the originating party. This is done when the ICSCF [306] performs a SCSCF node selection 10 procedure for identifying the SCSCF node [308] associated with the originating party, based on the special prefix. Since the SCSCF [308] of the originating party is already known, the ICSCF [306] does not interrogate the ICSCF [306] of the receiving party and directly interrogates the location and other details of the originating party using the SCSCF [308] of the originating party.
15
[0073] Fig. 4 illustrates an exemplary block diagram of a computing device [1000] upon which an embodiment of the present disclosure may be implemented. In an implementation, the computing device [1000] implements the method [200] for identifying a serving call session control function (SCSCF) node [108] associated with an originating party in a
20 multi-network environment by utilising the system [100]. In another implementation, the computing device [1000] itself implements the method [200] for identifying a serving call session control function (SCSCF) node [108] associated with an originating party in a multi-network environment using one or more units configured within the computing device [1000], wherein said one or more units are capable of implementing the features as
25 disclosed in the present disclosure.
[0074] The computing device [1000] may include a bus [1002] or other communication mechanism for communicating information, and a hardware processor [1004] coupled with bus [1002] for processing information. The hardware processor [1004] may be, for 30 example, a general-purpose microprocessor. The computing device [1000] may also include a main memory [1006], such as a random-access memory (RAM), or other dynamic storage device, coupled to the bus [1002] for storing information and instructions to be executed by the processor [1004]. The main memory [1006] also may be used for storing
19

temporary variables or other intermediate information during execution of the instructions to be executed by the processor [1004]. Such instructions, when stored in non-transitory storage media accessible to the processor [1004], render the computing device [1000] into a special-purpose machine that is customized to perform the operations specified in the 5 instructions. The computing device [1000] further includes a read only memory (ROM) [1008] or other static storage device coupled to the bus [1002] for storing static information and instructions for the processor [1004].
[0075] A storage device [1010], such as a magnetic disk, optical disk, or solid-state drive
10 is provided and coupled to the bus [1002] for storing information and instructions. The
computing device [1000] may be coupled via the bus [1002] to a display [1012], such as a
cathode ray tube (CRT), Liquid crystal Display (LCD), Light Emitting Diode (LED)
display, Organic LED (OLED) display, etc. for displaying information to a computer user.
An input device [1014], including alphanumeric and other keys, touch screen input means,
15 etc. may be coupled to the bus [1002] for communicating information and command
selections to the processor [1004]. Another type of user input device may be a cursor
controller [1016], such as a mouse, a trackball, or cursor direction keys, for communicating
direction information and command selections to the processor [1004], and for controlling
cursor movement on the display [1012]. This input device typically has two degrees of
20 freedom in two axes, a first axis (e.g., x) and a second axis (e.g., y), that allow the device
to specify positions in a plane.
[0076] The computing device [1000] may implement the techniques described herein using customized hard-wired logic, one or more ASICs or FPGAs, firmware and/or
25 program logic which in combination with the computing device [1000] causes or programs the computing device [1000] to be a special-purpose machine. According to one embodiment, the techniques herein are performed by the computing device [1000] in response to the processor [1004] executing one or more sequences of one or more instructions contained in the main memory [1006]. Such instructions may be read into the
30 main memory [1006] from another storage medium, such as the storage device [1010]. Execution of the sequences of instructions contained in the main memory [1006] causes the processor [1004] to perform the process steps described herein. In alternative
20

embodiments, hard-wired circuitry may be used in place of or in combination with software instructions.
[0077] The computing device [1000] also may include a communication interface [1028] 5 coupled to the bus [1002]. The communication interface [1028] provides a two-way data communication coupling to a network link [1020] that is connected to a local network [1022]. The local network [1022] may be connected a host [1024]. For example, the communication interface [1028] may be an integrated services digital network (ISDN) card, cable modem, satellite modem, or a modem to provide a data communication connection
10 to a corresponding type of telephone line. As another example, the communication interface [1028] may be a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links may also be implemented. In any such implementation, the communication interface [1028] sends and receives electrical, electromagnetic or optical signals that carry digital data streams representing various types
15 of information.
[0078] The computing device [1000] can send messages and receive data, including program code, through the network(s), the network link [1020] and the communication interface [1028]. In the Internet example, a server [1030] might transmit a requested code 20 for an application program through the Internet [1028], the ISP [1026], the local network [1022] and the communication interface [1028]. The received code may be executed by the processor [1004] as it is received, and/or stored in the storage device [1010], or other non¬volatile storage for later execution.
25 [0079] Further, in accordance with the present disclosure, it is to be acknowledged that the functionality described for the various the components/units can be implemented interchangeably. While specific embodiments may disclose a particular functionality of these units for clarity, it is recognized that various configurations and combinations thereof are within the scope of the disclosure. The functionality of specific units as disclosed in the
30 disclosure should not be construed as limiting the scope of the present disclosure. Consequently, alternative arrangements and substitutions of units, provided they achieve the intended functionality described herein, are considered to be encompassed within the scope of the present disclosure.

[0080] As is evident from the above, the present disclosure provides a technically advanced solution which involves selecting a SCSCF based on originating party number. A user can now be charged for multiple data communication sessions initiated by special 5 application server (AS) [104]. Also, legal implication of tracing back of call to originating party in case of multiple receiving parties involved, is now possible to be identified for example, using the present disclosure, multiple calls can be set up or initiated at the same time by the originating party. And, since the SCSCF [108] at the originating party end is interrogated by the ICSCF [106], the need of implementing separate billing server at the 10 AS [104] at the receiving end is dispensed with, and only the billing server at the originating party’s end is implemented. Also, a user can now be charged for multiple data communication sessions initiated by the AS [104]. Also, legal implication of tracing back of call to originating party in case of multiple receiving parties involved, is now possible to be identified.
15
[0081] While considerable emphasis has been placed herein on the disclosed embodiments, it will be appreciated that many embodiments can be made and that many changes can be made to the embodiments without departing from the principles of the present disclosure. These and other changes in the embodiments of the present disclosure 20 will be apparent to those skilled in the art, whereby it is to be understood that the foregoing descriptive matter to be implemented is illustrative and non-limiting.

We Claim:
1. A method [200] for identifying a serving call session control function (SCSCF)
node [108] associated with an originating party, the method [200] comprising:
- identifying, at an interrogating call session control function (ICSCF) node
5 [106] associated with a receiving party, by an identification unit [107], a
special prefix, wherein the special prefix is attached in a contact number of the
receiving party, by an application server (AS) [104] connected to the SCSCF
node [108] associated with the originating party, upon an initiation of a call
from the originating party to the receiving party;
10 - performing, at the ICSCF node [106] associated with the receiving party, by a
selection unit [109], a SCSCF node selection procedure for identifying the SCSCF node [108] associated with the originating party, based on the special prefix; and
- identifying, at the ICSCF node [106] associated with the receiving party, by
15 the identification unit [107], the SCSCF node [108] associated with the
originating party based on a configuration of the ICSCF node [106].
2. The method [200] as claimed in claim 1, wherein prior to the attaching, by the AS
[104], the special prefix in the contact number of the receiving party, the method
20 [200] comprising:
- receiving, by the SCSCF [108] associated with the originating party from a
user device, the call initiated by the user device.
3. The method [200] as claimed in claim 1, the method [200] further comprising:
25 - initiating, by the AS [104] connected to the SCSCF node [108] associated with
the originating party, the call to the receiving party.
4. The method [200] as claimed in claim 3, wherein the initiating, by the AS [104]
connected to the SCSCF node [108] associated with the originating party, the call
30 to the receiving party, comprises:
- sending, by the AS [104] to the ICSCF node [106] associated with the receiving party, a session initiation protocol (SIP) message,

wherein the SIP message comprises the special prefix attached in the contact number of the receiving party.
5. A system [100] for identifying a serving call session control function (SCSCF)
node [108] associated with an originating party, the system [100] comprising:
- an interrogating call session control function (ICSCF) node [106] associated
with a receiving party, the ICSCF node [106] configured to have:
o an identification unit [107] configured to identify, a special prefix, wherein the special prefix is attached in a contact number of the receiving party, by an application server (AS) [104] connected to the SCSCF node [108] associated with the originating party, upon an initiation of a call from the originating party to the receiving party; and
o a selection unit [109] connected to at least the identification unit [107], wherein the selection unit [109] being configured to perform, a SCSCF node selection procedure for identification of the SCSCF node [108] associated with the originating party based on the special prefix,
wherein the identification unit [107] is further configured to identify, the SCSCF node [108] associated with the originating party based on the configuration of the ICSCF node [106].
6. The system [100] as claimed in claim 5, wherein prior to the AS [104] attaching
the special prefix in the contact number of the receiving party, the SCSCF [108]
associated with the originating party is configured to:
- receive the call initiated by a user device.
7. The system [100] as claimed in claim 5, wherein the AS [104] connected to the
SCSCF node [108] associated with the originating party is further configured to:
- initiate the call to the receiving party.
8. The system [100] as claimed in claim 7, wherein the AS [104] connected to the
SCSCF node [108] associated with the originating party, for initiating the call to the receiving party, is configured to:

- send, to the ICSCF node [106] associated with the receiving party, a session initiation protocol (SIP) message,
wherein the SIP message comprises the special prefix attached in the contact number of the receiving party.