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 HANDOVER BETWEEN A FIRST NETWORK AND A SECOND NETWORK”
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.

5 METHOD AND SYSTEM FOR HANDOVER BETWEEN A FIRST NETWORK AND
A SECOND NETWORK
FIELD OF INVENTION
10 [0001] Embodiments of the present disclosure generally relate to network performance
management systems. More particularly, embodiments of the present disclosure relate to methods and system for handover between a first network and a second network.
BACKGROUND
15
[0002] The following description of the related art is intended to provide background
information pertaining to the field of the disclosure. This section may include certain aspects of the art that may be related to various features of the present disclosure. However, it should be appreciated that this section is used only to enhance the understanding of the reader with
20 respect to the present disclosure, and not as admissions of the prior art.
[0003] Wireless communication technology has rapidly evolved over the past few
decades, with each generation bringing significant improvements and advancements. The first generation of wireless communication technology was based on analog technology and offered
25 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-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
30 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 communication technology has become more advanced, sophisticated, and capable of delivering more services to its users.
35 [0004] In the field of telecommunication systems, the seamless transition between
different access networks is important for ensuring an uninterrupted connectivity and a smooth user experience. However, in the current versions of the telecommunication systems, a handover process between a 3rd Generation Partnership Project (3GPP) and a non-3GPP access
2

5 networks faces several issues which result in significant disruption and service interruptions.
One of the primary issue that hampers the handover process is a lack of a guarantee for seamless
transition. Also, the telecommunication system often fails to maintain a continuous connection
when a user moves between different access networks such as transitioning from a cellular
network to a Wireless Fidelity (Wi-Fi) network or vice versa and this type of failure led to
10 frequent loss of data packets. For instance, due to the asynchronous nature of different access
networks, a synchronization issue may arise when the data packets are transferred between them. Additionally, variations in latency between networks also lead to delays in packet delivery.
15 [0005] Moreover, during the handover procedure, users would often experience a
temporary loss of audio or data transmission, commonly known as muting, at a User Equipment (UE) end. This muting occurred as the system reconfigures itself to establish a connection with a new network, resulting in a disruption of an ongoing communication flow. Consequently, the users relying on real-time applications such as a Voice over IP (VoIP) or streaming services
20 also encounter noticeable interruptions in their calls or media playback. In applications where
a continuous and uninterrupted connection is paramount, such as VoIP calls or streaming videos, even minor disruptions could significantly impact a user perception of the service quality.
25 [0006] Therefore, in light of the foregoing discussion, there exists a need to provide a
method and system for seamless handover between a 3GPP and a non-3GPP access networks.
SUMMARY
30 [0007] This section is provided to introduce certain aspects of the present 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.
[0008] An aspect of the present disclosure may relate to a method for handover between a
35 first network and a second network, the method comprising receiving, by a transceiver unit via
a session management function (SMF), a general packet radio services tunnelling protocol -user plane internet protocol (IP)/fully qualified tunnel endpoint identifier (GTP-U F-TEID) of a default IP multimedia subsystem (IMS) bearer during a handover procedure. The method
3

5 further comprises updating, by a processing unit via the SMF, the GTP-U F-TEID of the default
IMS bearer to align with a dedicated bearer. The method further comprises forwarding, by the
processing unit, all real-time transport protocol (RTP) packets through the updated GTP-U F-
TEID of the default bearer. The method further comprises updating, by the processing unit, the
GTP-U F-TEID of an access corresponding to the dedicated bearer at the SMF upon completion
10 of the handover procedure.
[0009] In an exemplary aspect of the present disclosure, the handover procedure is
between the first network and the second network.
15 [00010] In an exemplary aspect of the present disclosure, the GTP-U F-TEID is received
during the handover from an Evolved Packet System (EPS) to a non-3GPP access or a 5G to the non-3GPP access.
[00011] In an exemplary aspect of the present disclosure, the GTP-U F-TEID is received in
20 a modify bearer request during the handover from the non-3GPP access to the EPS.
[00012] In an exemplary aspect of the present disclosure, the method further comprises
sending, by the transceiver unit, an IP/TEID associated with the default bearer inside a forwarding action rule (FAR) corresponding to the dedicated bearer from the SMF.
25
[00013] Another aspect of the present disclosure may relate to a system for handover
between a first network and a second network. The system comprises of transceiver unit configured to receive via a session management function (SMF), a general packet radio services tunnelling protocol - user plane internet protocol fully qualified tunnel endpoint
30 identifier (GTP-U F-TEID) of a default internet protocol multimedia subsystem (IMS) bearer
during a handover procedure. The system comprises a processing unit connected at least with the transceiver unit and the processing unit is configured to update, via the SMF, the GTP-U F-TEID of the default bearer to align with a dedicated bearer. The processing unit is further configured to forward, real-time transport protocol (RTP) packets through the updated GTP-U
35 F-TEID of the default bearer. The processing unit is further configured to update, the GTP-U
F-TEID of an access corresponding to the dedicated bearer at the SMF upon completion of the handover procedure.
4

5 [00014] Yet another aspect of the present disclosure may relate to a non-transitory computer
readable storage medium storing instructions for handover between a first network and a second network, the instructions include executable code which, when executed by a one or more units of a system, causes: a transceiver unit of the system to receive via a session management function (SMF), a general packet radio services tunnelling protocol - user plane
10 internet protocol fully qualified tunnel endpoint identifier (GTP-U F-TEID) of a default
internet protocol multimedia subsystem (IMS) bearer during a handover procedure; a processing unit of the system to update, via the SMF, the GTP-U F-TEID of the default bearer to align with a dedicated bearer, forward, real-time transport protocol (RTP) packets through the updated GTP-U F-TEID of the default bearer, update, the GTP-U F-TEID of an access
15 corresponding to the dedicated bearer at the SMF upon completion of the handover procedure.
OBJECTS OF THE INVENTION
[00015] Some of the objects of the present disclosure, which at least one embodiment
20 disclosed herein satisfies are listed herein below.
[00016] It is an object of the present disclosure to provide a method and system for seamless
handover between a first network and a second network such as between a 3rd Generation Partnership Project (3GPP) and a non-3GPP access networks.
25
[00017] It is another object of the present disclosure to provide a method and system for
handover between a first network and a second network that achieves a seamless handover between a 3GPP Access and a non-3GPP access. This ensures that the transition from one type of access to another does not interrupt the user's service.
30
[00018] It is another object of the present disclosure to provide a method and system for
handover between a first network and a second network that minimize or eliminate packet loss during the handover procedure. This helps to maintain a high quality of service for the user, especially for data-intensive applications like streaming video or a Voice over IP (VoIP).
35
[00019] It is another object of the present disclosure to provide a method and system for
handover between a first network and a second network that aims to eliminate muting observed
5

5 at a User Equipment (UE) end during the handover procedure, ensuring continuous and
uninterrupted service.
[00020] It is another object of the present disclosure to provide a method and system for
handover between a first network and a second network that aims to enhance the user's
10 experience, providing smooth and uninterrupted service regardless of the type of access used.
[00021] It is another object of the present disclosure to provide a method and system for
handover between a first network and a second network that seeks to be compliant with 3GPP
specifications, ensuring that its implementation is consistent with industry standards and can
15 be integrated with existing infrastructure.
[00022] It is yet another object of the present disclosure to provide a method and system for
handover between a first network and a second network that facilitate the timely initiation of
the dedicated bearer procedure establishment, even before the successful establishment of the
20 default bearer, to minimize delays during the handover process.
DESCRIPTION OF THE DRAWINGS
[00023] The accompanying drawings, which are incorporated herein, and constitute a part
25 of this disclosure, illustrate exemplary embodiments of the disclosed methods and systems 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. Also, the embodiments shown in the
figures are not to be construed as limiting the disclosure, but the possible variants of the method
30 and system according to the disclosure are illustrated herein to highlight the advantages of the
disclosure. It will be appreciated by those skilled in the art that disclosure of such drawings includes disclosure of electrical components or circuitry commonly used to implement such components.
35 [00024] FIG. 1 illustrates an exemplary block diagram representation of 5th generation core
(5GC) network architecture.
6

5 [00025] FIG. 2 illustrates an exemplary block diagram of a computing device upon which
the features of the present disclosure may be implemented in accordance with exemplary implementation of the present disclosure.
[00026] FIG. 3 illustrates an exemplary block diagram of a system for handover between a
10 first network and a second network in accordance with exemplary implementations of the
present disclosure.
[00027] FIG. 4 illustrates a method flow diagram indicating a process for handover between
a first network and a second network in accordance with exemplary implementations of the
15 present disclosure.
[00028] FIG. 5A illustrates an exemplary sequence flow diagram of handover process
between an Evolved Packet System (EPS) to a non-3GPP access in accordance with exemplary implementations of the present disclosure. 20
[00029] FIG. 5B illustrates an exemplary sequence flow diagram of handover process
between a non-3GPP access to a 4th Generation Evolved Packet System (4G EPS) in accordance with exemplary implementations of the present disclosure.
25 [00030] The foregoing shall be more apparent from the following more detailed description
of the disclosure.
DETAILED DESCRIPTION
30 [00031] In the following description, for the purposes of explanation, various specific
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 may each be used independently of one another or with any combination of other features. An individual feature
35 may not address any of the problems discussed above or might address only some of the
problems discussed above.
7

5 [00032] 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 without departing from the
10 spirit and scope of the disclosure as set forth.
[00033] 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 in
the art that the embodiments may be practiced without these specific details. For example,
15 circuits, systems, processes, and other components may be shown as components in block
diagram form in order not to obscure the embodiments in unnecessary detail.
[00034] 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
20 diagram. Although a flowchart may describe the operations as a sequential process, many of
the operations may 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.
25 [00035] The word “exemplary” and/or “demonstrative” is used herein to mean serving as
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
30 structures and techniques known to those of ordinary skill in the art. 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.
35
[00036] As used herein, a “processing unit” or “processor” or “operating processor”
includes one or more processors, wherein processor refers to any logic circuitry for processing instructions. A processor may be a general-purpose processor, a special purpose processor, a
8

5 conventional processor, a digital signal processor, a plurality of microprocessors, one or more
microprocessors in association with a (Digital Signal Processing) 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 the
10 working of the system according to the present disclosure. More specifically, the processor or
processing unit is a hardware processor.
[00037] As used herein, “a user equipment”, “a user device”, “a smart-user-device”, “a
smart-device”, “an electronic device”, “a mobile device”, “a handheld device”, “a wireless
15 communication device”, “a mobile communication device”, “a communication device” may
be any electrical, electronic and/or computing device or equipment, capable of implementing the features of the present disclosure. The user equipment/device may include, but is not limited to, a mobile phone, smart phone, laptop, a general-purpose computer, desktop, personal digital assistant, tablet computer, wearable device or any other computing device which is capable of
20 implementing the features of the present disclosure. Also, the user device may contain at least
one input means configured to receive an input from at least one of a transceiver unit, a processing unit, a storage unit, a detection unit and any other such unit(s) which are required to implement the features of the present disclosure.
25 [00038] As used herein, “storage unit” or “memory unit” refers to a machine or computer-
readable medium including any mechanism for storing information in a form readable by a computer or similar machine. For example, a computer-readable medium includes read-only memory (“ROM”), random access memory (“RAM”), magnetic disk storage media, optical storage media, flash memory devices or other types of machine-accessible storage media. The
30 storage unit stores at least the data that may be required by one or more units of the system to
perform their respective functions.
[00039] As used herein “interface” or “user interface refers to a shared boundary across
which two or more separate components of a system exchange information or data. The
35 interface may also be referred to a set of rules or protocols that define communication or
interaction of one or more modules or one or more units with each other, which also includes the methods, functions, or procedures that may be called.
9

5 [00040] As used herein “non-3GPP network” may be a network that includes one or more
of custom infrastructures, one or more proprietary infrastructures which are not compliant to a
3GPP defined infrastructure. Also, the 5G core network supports connectivity of user
equipment via the non-3GPP access networks such as Wireless Local Area Network (WLAN)
access network. Further the non-3GPP access includes access from, for instance, Wi-Fi,
10 WiMAX, fixed, and CDMA networks.
[00041] As used herein Evolved Packet Data Gateway (EPDG) ensures a secure data
transmission with the user equipment connected to an Evolved Packet Core (EPC) over an untrusted non-3GPP access.
15
[00042] All modules, units, components used herein, unless explicitly excluded herein, may
be software modules or hardware processors, the processors being a general-purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a
20 controller, a microcontroller, Application Specific Integrated Circuits (ASIC), Field
Programmable Gate Array circuits (FPGA), any other type of integrated circuits, etc.
[00043] As used herein the transceiver unit include at least one receiver and at least one
transmitter configured respectively for receiving and transmitting data, signals, information or
25 a combination thereof between units/components within the system and/or connected with the
system.
[00044] As discussed in the background section, in the realm of telecommunications,
ensuring seamless transitions between different access networks is crucial for uninterrupted
30 connectivity and user satisfaction. However, current systems face significant challenges during
handover processes between a 3rd Generation Partnership Project (3GPP) and a non-3GPP networks, leading to disruptions and packet losses. These issues stem from the lack of guaranteed seamless transitions, asynchronous network characteristics causing synchronization problems, and latency variations causing delays in packet delivery. Additionally, the user often
35 experiences temporary audio or data losses, known as muting during handovers, thus disrupting
communication flow and impacting real-time applications like Voice over Internet Protocol (VoIP) services or streaming services, and hence the current known solutions have several shortcomings. The present disclosure aims to overcome the above-mentioned and other
10

5 existing problems in this field of technology by providing a method and system of handover
between a first network and a second network that helps to achieve seamless handover from the first network, such as a 3GPP access, and the second network, such as a non-3GPP access. Additionally, the method and system of the present disclosure involve receiving the general packet radio services tunnelling protocol - user plane internet protocol - fully qualified tunnel
10 endpoint identifier (GTP-U F-TEID) of a default internet protocol multimedia subsystem
(IMS) bearer during a handover procedure. Subsequently, the GTP-U F-TEID of the default IMS bearer is updated to synchronize with a dedicated bearer, and the synchronization facilitates the seamless transfer of all Real-Time Transport Protocol (RTP) packets via the updated GTP-U F-TEID of the default bearer. Furthermore, upon the successful completion of
15 the handover procedure, the access corresponding to the dedicated bearer is also updated to
maintain uninterrupted connectivity and efficient data transmission between the two networks i.e., the first network and the second network.
[00045] FIG. 1 illustrates an exemplary block diagram representation of 5th generation core
20 (5GC) network architecture, in accordance with exemplary implementation of the present
disclosure. As shown in FIG. 1, the 5GC network architecture [100] includes a user equipment
(UE) [102], a radio access network (RAN) [104], an access and mobility management function
(AMF) [106], a Session Management Function (SMF) [108], a Service Communication Proxy
(SCP) [110], an Authentication Server Function (AUSF) [112], a Network Slice Specific
25 Authentication and Authorization Function (NSSAAF) [114], a Network Slice Selection
Function (NSSF) [116], a Network Exposure Function (NEF) [118], a Network Repository
Function (NRF) [120], a Policy Control Function (PCF) [122], a Unified Data Management
(UDM) [124], an application function (AF) [126], a User Plane Function (UPF) [128], a data
network (DN) [130], wherein all the components are assumed to be connected to each other in
30 a manner as obvious to the person skilled in the art for implementing features of the present
disclosure.
[00046] Radio Access Network (RAN) [104] is the part of a mobile telecommunications
system that connects user equipment (UE) [102] to the core network (CN) and provides access
35 to different types of networks (e.g., 5G network). It consists of radio base stations and the radio
access technologies that enable wireless communication.
11

5 [00047] Access and Mobility Management Function (AMF) [106] is a 5G core network
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.
10 [00048] Session Management Function (SMF) [108] is a 5G core network function
responsible for managing session-related aspects, such as establishing, modifying, and releasing sessions. It coordinates with the User Plane Function (UPF) for data forwarding and handles IP address allocation and QoS enforcement.
15 [00049] Service Communication Proxy (SCP) [110] is a network function in the 5G core
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.
[00050] Authentication Server Function (AUSF) [112] is a network function in the 5G core
20 responsible for authenticating UEs during registration and providing security services. It
generates and verifies authentication vectors and tokens.
[00051] Network Slice Specific Authentication and Authorization Function (NSSAAF)
[114] is a network function that provides authentication and authorization services specific to
25 network slices. It ensures that UEs can access only the slices for which they are authorized.
[00052] Network Slice Selection Function (NSSF) [116] 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. 30
[00053] Network Exposure Function (NEF) [118] is a network function that exposes
capabilities and services of the 5G network to external applications, enabling integration with third-party services and applications.
35 [00054] Network Repository Function (NRF) [120] is a network function that acts as a
central repository for information about available network functions and services. It facilitates the discovery and dynamic registration of network functions.
12

5 [00055] Policy Control Function (PCF) [122] is a network function responsible for policy
control decisions, such as QoS, charging, and access control, based on subscriber information and network policies.
[00056] Unified Data Management (UDM) [124] is a network function that centralizes the
10 management of subscriber data, including authentication, authorization, and subscription
information.
[00057] Application Function (AF) [126] is a network function that represents external
applications interfacing with the 5G core network to access network capabilities and services. 15
[00058] User Plane Function (UPF) [128] is a network function responsible for handling
user data traffic, including packet routing, forwarding, and QoS enforcement.
[00059] Data Network (DN) [130] refers to a network that provides data services to user
20 equipment (UE) in a telecommunications system. The data services may include but are not
limited to Internet services, private data network related services.
[00060] FIG. 2 illustrates an exemplary block diagram of a computing device [1000] upon
which the features of the present disclosure may be implemented in accordance with exemplary
25 implementation of the present disclosure. In an implementation, the computing device [1000]
may also implement a method for handover between a first network and a second network utilising the system. In another implementation, the computing device [1000] itself implements the method for handover between the first network and the second network using one or more units configured within the computing device [1000], wherein said one or more units are
30 capable of implementing the features as disclosed in the present disclosure.
[00061] 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 example, a
35 general purpose microprocessor. The computer system [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 temporary variables or other
13

5 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 computer system [1000] into a special-purpose machine that is
customized to perform the operations specified in the instructions. The computer system [1000]
further includes a read only memory (ROM) [1008] or other static storage device coupled to
10 the bus [1002] for storing static information and instructions for the processor [1004].
[00062] A storage device [1010], such as a magnetic disk, optical disk, or solid-state drive
is provided and coupled to the bus [1002] for storing information and instructions. The computer system [1000] may be coupled via the bus [1002] to a display [1012], such as a
15 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, 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 control [1016], such as a
20 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 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.
25 [00063] The computer system [1000] may implement the techniques described herein using
customized hard-wired logic, one or more ASICs or FPGAs, firmware and/or program logic which in combination with the computer system [1000] causes or programs the computer system [1000] to be a special-purpose machine. According to one implementation, the techniques herein are performed by the computer system [1000] in response to the processor
30 [1004] executing one or more sequences of one or more instructions contained in the main
memory [1006]. Such instructions may be read into the 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 implementations of the present disclosure, hard-wired circuitry
35 may be used in place of or in combination with software instructions.
[00064] The computer system [1000] also may include a communication interface [1018]
coupled to the bus [1002]. The communication interface [1018] provides a two-way data
14

5 communication coupling to a network link [1020] that is connected to a local network [1022].
For example, the communication interface [1018] may be an integrated services digital network
(ISDN) card, cable modem, satellite modem, or a modem to provide a data communication
connection to a corresponding type of telephone line. As another example, the communication
interface [1018] may be a local area network (LAN) card to provide a data communication
10 connection to a compatible LAN. Wireless links may also be implemented. In any such
implementation, the communication interface [1018] sends and receives electrical, electromagnetic or optical signals that carry digital data streams representing various types of information.
15 [00065] The computer system [1000] can send messages and receive data, including
program code, through the network(s), the network link [1020] and the communication interface [1018]. In the Internet example, a server [1030] might transmit a requested code for an application program through the Internet [1028], the ISP [1026], the host [1024], the local network [1022] and the communication interface [1018]. The received code may be executed
20 by the processor [1004] as it is received, and/or stored in the storage device [1010], or other
non-volatile storage for later execution.
[00066] Referring to FIG. 3, an exemplary block diagram of a system [300] for handover
between a first network and a second network is shown, in accordance with the exemplary
25 implementations of the present disclosure. The system [300] comprises at least one transceiver
unit [302], at least one processing unit [304], and at least one storage unit [306]. Also, all of the components/ units of the system [300] are assumed to be connected to each other unless otherwise indicated below. As shown in the figures all units shown within the system should also be assumed to be connected to each other. Also, in FIG. 3 only a few units are shown,
30 however, the system [300] may comprise multiple such units or the system [300] may comprise
any such numbers of said units, as required to implement the features of the present disclosure.
[00067] The system [300] is configured for handover between the first network and the
second network with the help of the interconnection between the components/units of the
35 system [300].
[00068] 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
15

5 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
disclosure should not be construed as limiting the scope of the present disclosure.
Consequently, alternative arrangements and substitutions of units, provided they achieve the
10 intended functionality described herein, are considered to be encompassed within the scope of
the present disclosure.
[00069] The transceiver unit [302] of the system [300] is configured to receive via a session
management function (SMF) [108], a general packet radio services tunnelling protocol - user
15 plane internet protocol fully qualified tunnel endpoint identifier (GTP-U F-TEID) of a default
internet protocol multimedia subsystem (IMS) bearer during a handover procedure.
[00070] The general packet radio services tunnelling protocol (GTP) is a protocol that is
used in a mobile telecommunication network preferably for a packet-switched data
20 transmission. Further, in the user plane is responsible for an actual transmission of one or more
user data packets between a mobile device i.e., a user device such as smartphone and the mobile telecommunication network. The user-plane internet protocol ensures that the one or more user data packets are routed properly through the mobile telecommunication network.
25 [00071] The fully qualified tunnel endpoint identifier is a unique identifier that is assigned
to an endpoint of a tunnel within the GTP-U protocol for distinguishing different tunnels and their respective endpoints within the network.
[00072] The default IP multimedia subsystem (IMS) bearer refers to a subsystem that is
30 responsible for delivering one or more multimedia services over one or more IP networks. The
bearer refers to a logical connection or a pathway that carries the data between the user device and the IMS network.
[00073] The handover procedure refers to a process of transferring an ongoing
35 communication session or connection from one base station (or cell) to another or between
different types of radio access technologies, while maintaining a seamless connectivity and quality of service of the user.
16

5 [00074] As disclosed herein, the handover procedure may be between the first network and
the second network, such as between a 3rd Generation Partnership Project (3GPP) (i.e., first network) and a non-3GPP access networks (i.e., the second network).
[00075] The present disclosure encompasses that the GTP-U F-TEID is received during the
10 handover from an Evolved Packet System (EPS) to a non-3GPP access or a 5G to the non-
3GPP access. The Evolved Packet System (EPS) is the core network architecture used in an
LTE (Long-Term Evolution) and later generations of mobile telecommunications networks,
such as a fifth generation (5G). The non-3GPP access refers to access technologies that are not
based on the 3rd Generation Partnership Project (3GPP) standards. The non-3GPP access
15 include various wireless technologies like Wireless Fidelity (Wi-Fi), Worldwide
Interoperability for Microwave Access (WiMAX) which operate outside a scope of traditional cellular networks governed by the 3GPP standards.
[00076] The present disclosure encompasses that the GTP-U F-TEID is received in a
20 modify bearer request during the handover from the non-3GPP access to the EPS. The modify
bearer request as used herein refers to a request to change one or more characteristics or one or more parameters associated with the bearer.
[00077] The processing unit [304] is connected at least with the transceiver unit [302] and
25 the processing unit [304] is configured to update, via the SMF [108], the GTP-U F-TEID of
the default bearer to align with a dedicated bearer.
[00078] The present disclosure encompasses that the processing unit [304] is further
configured to send an IP/TEID associated with the default bearer inside a forwarding action
30 rule (FAR) corresponding to the dedicated bearer from the SMF [108].
[00079] Also, it is to be noted that the FAR is a rule that is defined within the SMF [108]
and the FAR specifies how incoming packets are to be forwarded or routed based on a certain criteria or one or more conditions. 35
[00080] The processing unit [304] ensures that the GTP-U F-TEID of the default IMS
bearer is maintained up-to-date according to one or more instructions received from the SMF
17

5 [108] for maintaining an efficient and reliable communication for the one or more multimedia
services.
[00081] Thereafter, the processing unit [304] is configured to forward, real-time transport
protocol (RTP) packets through the updated GTP-U F-TEID of the default bearer. Further, the
10 GTP-U F-TEID of the default IMS bearer is a unique ID number for the data connection
between the UE and a IP network that keeps track of the data during transmission of the data between the UE and the IP network.
[00082] The RTP is a protocol to facilitate the real-time transmission of an audio, a video,
15 or other data over the one or more IP networks. The RTP is widely used in applications such
as a Voice over IP (VoIP) application, a video conferencing application, a streaming media application, and an online gaming application, where maintaining low latency and synchronized delivery of one or more media packets is crucial for a seamless user experience.
20 [00083] Thereafter, the processing unit [304] is configured to update, the GTP-U F-TEID
of the an access corresponding to the dedicated bearer at the SMF [108] upon completion of the handover procedure.
[00084] Referring to FIG. 4, a method flow diagram for handover between a first network
25 and a second network in accordance with exemplary implementations of the present disclosure
is depicted. In an implementation the method [400] is performed by the system [300]. Further, in an implementation, the system [300] may be present in a server device to implement the features of the present disclosure. Also, as shown in FIG. 4, the method [400] starts at step [402]. 30
[00085] At step [404], the method comprises receiving, by a transceiver unit [302] via a
session management function (SMF) [108], a general packet radio services tunnelling protocol - user plane internet protocol - fully qualified tunnel endpoint identifier (GTP-U F-TEID) of a default internet protocol multimedia subsystem (IMS) bearer during a handover procedure. 35
[00086] The general packet radio services tunnelling protocol (GTP) is a protocol that is
used in a mobile telecommunication network preferably for a packet-switched data transmission. Further, in the user plane is responsible for an actual transmission of one or more
18

5 user data packets between a mobile device i.e., a user device such as smartphone and the mobile
telecommunication network. The user-plane internet protocol ensures that the one or more user data packets are routed properly through the mobile telecommunication network.
[00087] The fully qualified tunnel endpoint identifier is a unique identifier that is assigned
10 to an endpoint of a tunnel within the GTP-U protocol for distinguishing different tunnels and
their respective endpoints within the network.
[00088] The default IP multimedia subsystem (IMS) bearer refers to a subsystem that is
responsible for delivering one or more multimedia services over one or more IP networks. The
15 bearer refers to a logical connection or a pathway that carries the data between the user device
and the IMS network.
[00089] The handover procedure refers to a process of transferring an ongoing
communication session or connection from one base station (or cell) to another or between
20 different types of radio access technologies, while maintaining a seamless connectivity and
quality of service of the user.
[00090] The present disclosure encompasses that the handover procedure is between the
first network and the second network such as between a 3rd Generation Partnership Project
25 (3GPP) (i.e., first network) and a non-3GPP access networks (i.e., the second network).
[00091] The present disclosure encompasses that the GTP-U F-TEID is received during the
handover from an Evolved Packet System (EPS) to a non-3GPP access or a 5G to the non-3GPP access. 30
[00092] The Evolved Packet System (EPS) is the core network architecture used in an LTE
(Long-Term Evolution) and later generations of mobile telecommunications networks, such as
a fifth generation (5G). The non-3GPP access refers to access technologies that are not based
35 on the 3rd Generation Partnership Project (3GPP) standards. The non-3GPP access include
various wireless technologies like Wireless Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (WiMAX) which operate outside a scope of traditional cellular networks governed by the 3GPP standards.
19

5
[00093] The present disclosure encompasses that the GTP-U F-TEID is received in a
modify bearer request during the handover from the non-3GPP access to the EPS. The modify
bearer request (MBR) include one or more information elements such as a Mobile Equipment
(ME) Identity (MEI), a User Location Information (ULI), a Radio Access Technology (RAT)
10 type, one or more indication flags.
[00094] At step [406], the method [400] comprises updating, by a processing unit [304] via
the SMF [108], the GTP-U F-TEID of the default IMS bearer to align with a dedicated bearer.
15 [00095] The present disclosure encompasses that the method further comprises sending, by
the transceiver unit [302], an IP/TEID associated with the default bearer inside a forwarding action rule (FAR) corresponding to the dedicated bearer from the SMF [108]. Also, it is to be noted that the FAR is a rule that is defined within the SMF [108] and the FAR specifies how incoming packets are to be forwarded or routed based on a certain criteria or one or more
20 conditions.
[00096] At step [408], the method [400] comprises forwarding, by the processing unit [304],
all real-time transport protocol (RTP) packets through the updated GTP-U F-TEID of the default bearer. 25
[00097] At step [410], the method [400] comprises updating, by the processing unit [304],
the GTP-U F-TEID of an access corresponding to the dedicated bearer at the SMF [108] upon completion of the handover procedure.
30 [00098] The method [400] terminates at step [412].
[00099] Referring to FIG. 5A, an exemplary sequence flow diagram of handover process
between an Evolved Packet System (EPS) to a non-3GPP access in accordance with exemplary
implementations of the present disclosure is shown. The handover process depicted in FIG. 5A
35 may be implemented by the system [300]. As depicted in FIG. 5A, at step S1, user equipment
(UE) [502] or a radio access network (RAN) initiates a handover request transmitted to the non-3GPP access.
20

5 [000100] At step S2, a general packet radio services tunnelling protocol - user plane internet
protocol fully qualified tunnel endpoint identifier (GTP-U F-TEID) of a default IP Multimedia Subsystem (IMS) bearer is transmitted from the non-3GPP access to the Session Management Function (SMF) [108].
10 [000101] At step S3, the SMF [108] transmits a Session Modification Request (SMR)
including fully qualified tunnel endpoint identifier (F-TEID) for both default and dedicated bearers to a User Plane Function (UPF) [128].
[000102] At step S4, the UPF [128] responds to the SMF [108] acknowledging the Session
15 Modification Request.
[000103] At step S5, the SMF [108] transmits a response containing the F-TEID of the default bearer to the non-3GPP access.
20 [000104] At step S6, the UE [502] transmits a success response to the non-3GPP access
indicating successful handover.
[000105] At step S7, the SMF [108] sends a creation request of a dedicated bearer from the non-3GPP access. Further, no packet loss is there at step S7. 25
[000106] At step S8, the non-3GPP access responds to the creation request of the dedicated bearer.
[000107] At step S9, a F-TEID of the dedicated bearer is updated at the User Plane Function
30 (UPF) [128] ensuring seamless connectivity.
[000108] Referring to FIG. 5B, an exemplary sequence flow diagram of handover process
between a non-3GPP access to a 4th Generation Evolved Packet System (4G EPS) in
accordance with exemplary implementations of the present disclosure is shown. The handover
35 process depicted in FIG. 5B may be implemented by the system [300]. As depicted in FIG. 5B,
at step S1, a User Equipment (UE) or Radio Access Network (RAN) [104] sends a handover request to the Mobility Management Entity (MME) [506].
21

5 [000109] At step S2, the MME [506] forwards a Handover Indication, also known as CSR
(Change of Serving RAN), to an Evolved Packet Data Gateway (EPDG) [504] associated with
the 4th Generation Evolved Packet System (EPS) Further, as used herein “the EPDG in 3GPP
technology is a network traffic controller associated with a data traffic of the UE. Further, the
EPDG manages a data transmission flow between the UE and a network service such as internet
10 service, wherein the UE is connected to the network.
[000110] At step S3, the EPDG [504] sends a Session Modification Request (SMR) to a Session Management Function (SMF) [108].
15 [000111] At step S4, the SMF [108] responds to the SMR with necessary updates or
acknowledgments.
[000112] At step S5, the EPDG [504] acknowledges the Handover Indication with a CSR (Change of Serving RAN) response to the MME [506]. 20
[000113] At step S6, the UE [502] or RAN [104] confirms acceptance of the handover to the MME [506].
[000114] At step S7, the MME [506] sends a Modify Bearer Request (MBR) containing a
25 Fully Qualified Tunnel Endpoint Identifier (F-TEID) for a default bearer to the EPDG [504].
[000115] At step S8, the SMF [108] sends a Session Modification Request (SMR) to update the F-TEID dedicated bearers and a F-TEID of default bearer to a User Plane Function (UPF) [128]. 30
[000116] At step S9, the UPF [128] responds to the SMR with necessary updates or acknowledgments.
[000117] At step S10, the EPDG [504] acknowledges a session modifications made with a
35 response to the MME [506].
[000118] At step 11, the SMF [108] requests the EPDG [504] to create a dedicated bearer via a Create Bearer Request (CBR). There is no packet loss at this step. Further, the EPDG
22

5 handles the received CBR for the dedicated bearer creation. The CBR include a bearer context
information of the dedicated bearer to be created. Further the bearer context information may include User Plane Function (UPF) and an information related to Quality of Service (QoS).
[000119] At step S12, the EPDG [504] acknowledges the creation of the dedicated bearer
10 with a response to the SMF [108].
[000120] The present disclosure further discloses a non-transitory computer readable storage medium storing instructions for handover between a first network and a second network, the instructions include executable code which, when executed by a one or more units of a system,
15 causes: a transceiver unit [302] of the system to receive via a session management function
(SMF) [108], a general packet radio services tunnelling protocol - user plane internet protocol fully qualified tunnel endpoint identifier (GTP-U F-TEID) of a default internet protocol multimedia subsystem (IMS) bearer during a handover procedure; a processing unit [304] of the system to update, via the SMF [108], the GTP-U F-TEID of the default bearer to align with
20 a dedicated bearer, forward, real-time transport protocol (RTP) packets through the updated
GTP-U F-TEID of the default bearer; and update, the GTP-U F-TEID of an access corresponding to the dedicated bearer at the SMF [108] upon completion of the handover procedure.
25 [000121] In order to understand the present solution better, let us consider an exemplary
scenario wherein the method and system of the present disclosure may be implemented in a telecommunication organization for performing a handover between an Evolved Packet System (EPS) network (i.e., Long-Term Evolution (LTE)) (i.e., a first network) and a Wireless Fidelity (Wi-Fi) network (i.e., a second network). For instance, a mobile subscriber (i.e., user) is using
30 a voice-over LTE (VoLTE) service on their smartphone (i.e., User Equipment (UE)) while
connected to the LTE network. As the user moves out of LTE coverage into an area with Wi-Fi coverage, the network initiates a handover process to seamlessly transition the ongoing VoLTE call to the Wi-Fi network. The transceiver unit [302] detects the weakening LTE signal and initiates a handover request to the MNO's Mobility Management Entity (MME) [506]. The
35 MME [506], via the Session Management Function (SMF) [108], receives the GTP-U F-TEID
of the default IMS bearer associated with the VoLTE call. The processing unit [304] within the MNO's network infrastructure, controlled by the SMF [108], updates the GTP-U F-TEID of the default IMS bearer to align with a dedicated bearer reserved for Wi-Fi traffic. The
23

5 processing unit [304] ensures that all real-time transport protocol (RTP) packets carrying the
VoLTE call are forwarded through the updated GTP-U F-TEID of the default bearer, now
aligned with the Wi-Fi dedicated bearer. Upon successful completion of the handover
procedure, the processing unit [304] updates the GTP-U F-TEID associated with the Wi-Fi
access point at the SMF [108], indicating that the VoLTE call is now being routed through the
10 Wi-Fi network. As part of enhancing QoS (Quality of Service), the processing unit [304] may
send an IP/TEID associated with the default bearer (IP address and Tunnel Endpoint Identifier) inside a Forwarding Action Rule (FAR) corresponding to the dedicated Wi-Fi bearer from the SMF [108], which helps in efficient routing and management of traffic within the network.
15 [000122] As is evident from the above, the present disclosure provides a technically
advanced solution for handover between a first network and a second network. The present
solution enables smooth transitions between a 3rd Generation Partnership Project (3GPP)
network (i.e., the first network) and a non-3GPP access network (i.e., the second network) and
ensures uninterrupted connectivity for users as they move between different types of networks.
20 Additionally, by minimizing packet loss during handover procedures, the present solution
significantly enhances experience of the user, which allows the users to maintain their
connections without disruption. Also, during the handover process, the Session Management
Function (SMF) dynamically updates a general packet radio services tunnelling protocol - user
plane internet protocol - fully qualified tunnel endpoint identifier (GTP-U F-TEID) of the
25 default bearer to align with the dedicated bearer for ensuring efficient utilization of network
resources and seamless handover. Moreover, all Real-Time Transport Protocol (RTP) packets
are efficiently routed through the updated GTP-U F-TEID of the default bearer, contributing
to the seamless transfer of data between networks and maintaining the quality of service for
users. Upon completion of the handover procedure the SMF further updates the GTP-U F-
30 TEID of the access corresponding to the dedicated bearer. Further, the SMF further updates the
GTP-U F-TEID of the access corresponding to the dedicated bearer. Hence, the present solution
provides a technically advanced approach to management for handover processes, thereby
enhancing connectivity and delivering a seamless user experience across diverse network
environments.
35
[000123] While considerable emphasis has been placed herein on the disclosed implementations, it will be appreciated that many implementations can be made and that many changes can be made to the implementations without departing from the principles of the
24

5 present disclosure. These and other changes in the implementations of the present disclosure
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.
25

I/We Claim:
1. A method [400] for handover between a first network and a second network, the method
comprising:
receiving, by a transceiver unit [302] via a session management function (SMF) [108], a general packet radio services tunnelling protocol - user plane internet protocol - fully qualified tunnel endpoint identifier (GTP-U F-TEID) of a default internet protocol multimedia subsystem (IMS) bearer during a handover procedure;
updating, by a processing unit [304] via the SMF [108], the GTP-U F-TEID of the default IMS bearer to align with a dedicated bearer;
forwarding, by the processing unit [304], all real-time transport protocol (RTP) packets through the updated GTP-U F-TEID of the default bearer; and
updating, by the processing unit [304], the GTP-U F-TEID of an access corresponding to the dedicated bearer at the SMF [108] upon completion of the handover procedure.
2. The method [400] as claimed in claim 1, wherein the handover procedure is between the first network and the second network.
3. The method [400] as claimed in claim 2, wherein the GTP-U F-TEID is received during the handover from an Evolved Packet System (EPS) to a non-3GPP access or a 5G to the non-3GPP access.
4. The method [400] as claimed in claim 3, wherein the GTP-U F-TEID is received in a modify bearer request during the handover from the non-3GPP access to the EPS.
5. The method [400] as claimed in claim 1, the method further comprises sending, by the transceiver unit [302], an IP/TEID associated with the default bearer inside a forwarding action rule (FAR) corresponding to the dedicated bearer from the SMF [108].
6. A system [300] for handover between a first network and a second network, the system [300] comprising:
a transceiver unit [302] configured to receive via a session management function (SMF) [108], a general packet radio services tunnelling protocol - user plane internet protocol fully qualified tunnel endpoint identifier (GTP-U F-TEID) of a default internet protocol multimedia subsystem (IMS) bearer during a handover procedure; and
26

a processing unit [304] connected at least with the transceiver unit [302], the processing unit [304] is configured to:
o update, via the SMF [108], the GTP-U F-TEID of the default bearer
to align with a dedicated bearer, o forward, real-time transport protocol (RTP) packets through the
updated GTP-U F-TEID of the default bearer, and o update, the GTP-U F-TEID of an access corresponding to the dedicated bearer at the SMF [108] upon completion of the handover procedure.
7. The system [300] as claimed in claim 6, wherein the handover procedure is between the first network and the second network.
8. The system [300] as claimed in claim 7, wherein the GTP-U F-TEID is received during the handover from an Evolved Packet System (EPS) to a non-3GPP access or a 5G to the non-3GPP access.
9. The system [300] as claimed in claim 8, wherein the GTP-U F-TEID is received in a modify bearer request during the handover from the non-3GPP access to the EPS.
10. The system [300] as claimed in claim 6, wherein the transceiver unit [302] is further configured to send an IP/TEID associated with the default bearer inside a forwarding action rule (FAR) corresponding to the dedicated bearer from the SMF [108].
Dated this 12th day of July 2023
(GARIMA SAHNEY)
IN/PA-1826
AGENT FOR THE APPLICANT(S)
OF SAIKRISHNA & ASSOCIATES