WO2025013018A1

WO2025013018A1 - Method and system for managing a packet data unit session establishment in a network

Info

Publication number: WO2025013018A1
Application number: PCT/IN2024/051066
Authority: WO
Inventors: Mukta Shetty; Aayush Bhatnagar; Alok Bhaskar; Sanjeev Kumar; Aditya Gupta; Apoorva Khamesra; Sachin Kumawat; Gaurav NARAYAN
Original assignee: Jio Platforms Ltd
Current assignee: Jio Platforms Ltd
Priority date: 2023-07-07
Filing date: 2024-07-04
Publication date: 2025-01-16
Anticipated expiration: 2026-01-07

Abstract

The present disclosure relates to a method and system for managing Packet Data Unit (PDU) session establishment in a network. A first network function (NF), receives, a PDU session establishment request for a UE, and transmits, a policy control create request for the UE to a second NF. The second NF determines, one of a presence and an absence of an existing policy session associated with a set of attributes for the UE. The second NF receives a maximum permitted policy sessions and a count of established policy sessions for a subset of attributes, in an event of the absence of the existing policy session. The second NF determines whether the count of established policy sessions is one of below and equal to the maximum permitted policy sessions. The second NF accepts the PDU session establishment request count of established policy sessions is below the maximum permitted policy sessions.

Description

METHOD AND SYSTEM FOR MANAGING A PACKET DATA UNIT SESSION ESTABLISHMENT IN A NETWORK

FIELD OF INVENTION

[0001] Embodiments of the present disclosure generally relate to wireless communication systems. More particularly, embodiments of the present disclosure relate to method and system for managing a packet data unit (PDU) session establishment in a network.

BACKGROUND

[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 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 antilog 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-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 communication technology has become more advanced, sophisticated, and capable of delivering more services to its users. As the wireless communication technology has evolved to a great extent, the number of users/subscribers of the wireless networks has also increased to a great extent and it is important for the wireless networks to provide better and smooth services to its subscribers. Session management plays a critical role in providing better services to the customers/subscribers of a telecom network. Improved session management may lead to an improved customer experience. Also, an increased number of sessions for the subscribers may create various problems at a network end and hence impact the user experience and network performance. Therefore, it is required to provide a session management solution that can efficiently handle the sessions created for the subscribers.

[0004] Currently, 3GPP does not define any specific way to limit the number of sessions that can be created for individual subscribers. This may create problems when network fluctuations occur where multiple sessions (SM Policy Sessions or PDU Binding Sessions) get created for an individual subscriber. Also, this may result in consuming all important resources of the NFs (PCF, BSF and CHF-PC) unnecessarily. Further, many of those created sessions would be stale sessions or non-live sessions which may also result in additional signalling traffic to be sent after stale session audit is done.

[0005] Thus, there exists an imperative need in the art to provide a solution: (1) that can overcome the limitations of the existing solutions, and (2) by which NFs can avoid additional signalling and conserve the compute, memory and storage resources allocated to NF (PCF/ BSF/ CHF-PC), which the present disclosure aims to address.

SUMMARY

[0006] 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.

[0007] An aspect of the present disclosure may relate to a method for managing a Packet Data Unit (PDU) session establishment in a network. The method comprises receiving the PDU session establishment request for a User Equipment (UE), by a first network function (NF). The method further comprises transmitting a policy control create request from the first NF to a second NF. The policy control create request comprises a set of attributes associated with the PDU session establishment request for the UE. Also, the method comprises determining, by the second NF, one of a presence and an absence of an existing policy session associated with the set of attributes for the UE. In addition, the method comprises receiving, by the second NF, maximum permitted policy sessions and a count of established policy sessions, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy session. Also, the method comprises determining, by the second NF, whether the count of the established policy control sessions is one of: below and equal to the maximum permitted policy sessions associated with the subset of attributes. Further, the method comprises accepting, by the second NF, the PDU session establishment request from the UE, based on the determination that the count of established policy sessions is below the maximum permitted policy sessions.

[0008] In another exemplary aspect of the present disclosure, the method further comprises deleting, by the second NF, the existing policy session for the UE, in an event of the presence of the existing policy session for the UE and accepting, by the second NF, the PDU session establishment request from the UE.

[0009] In another exemplary aspect of the present disclosure, the method further comprises deleting, by the second NF, a policy session from the established policy sessions, based on the determination that the count of established policy sessions is equal to the maximum permitted policy sessions.

[0010] In an exemplary aspect of the present disclosure, deleting the policy session from the established policy sessions, is determined based on a timestamp associated with each of the policy session from the established policy sessions.

[0011] In yet another exemplary aspect of the present disclosure, the set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID.

[0012] In another exemplary aspect of the present disclosure, the subset of attributes of the set of attributes comprises at least the SUPI, DNN, and the network slice.

[0013] In another exemplary aspect of the present disclosure, the first NF is a Session Management Function (SMF) in the network.

[0014] In yet another exemplary aspect of the present disclosure, the method further comprises the second NF is a Policy Control Function (PCF) in the network.

[0015] In another exemplary aspect of the present disclosure, the method further comprises transmitting, by the second NF, to a third NF, a management register request for the UE comprising the subset of attributes. The method further comprises receiving, by the third NF, a maximum permitted binding sessions for the subset of attributes. The method further comprises receiving, by the third NF, a count of existing binding sessions for the subset of attributes. The method comprises determining, by the third NF, whether the count of the existing binding sessions is one of below and equal to the maximum permitted binding sessions. The method further comprises accepting, by the third NF, the management register request from the second NF, based on the determining that the count of the existing binding sessions is below the maximum permitted binding sessions. In addition, the method comprises transmitting, by the third NF, an acceptance response for the management register request, to the second NF.

[0016] In another exemplary aspect of the present disclosure, based on the determination that the count of the existing binding sessions is equal to the maximum permitted binding sessions, the third NF determines one of a rejected response and an acceptance response based on a flag value in a user configurable table.

[0017] In another exemplary aspect of the present disclosure, the rejected response is transmitted to the second NF, based on a true value of the flag in the user configurable table.

[0018] In another exemplary aspect of the present disclosure, the acceptance response is transmitted to the second NF, based on a false value of the flag in the user configurable table.

[0019] In another exemplary aspect of the present disclosure, the acceptance response comprises deleting a binding session of the existing binding sessions for the subset of attributes.

[0020] In yet another exemplary aspect of the present disclosure, deleting the binding session from the existing binding sessions is determined based on a timestamp associated with each binding session of the existing binding sessions.

[0021] In another exemplary aspect of the present disclosure, the third NF is a Binding Support Function (BSF) in the network.

[0022] In another exemplary aspect of the present disclosure, the method comprises transmitting, by the second NF, to a fourth NF, a spending limit control session request associated with the subset of attributes. The method further comprises receiving, by the fourth NF, a maximum permitted spending limit control sessions for the subset of attributes. The method comprises receiving, by the fourth NF, a count of existing spending limit control sessions for the subset of attributes. Also, the method comprises determining, by the fourth NF, whether the count of the existing spending limit control sessions is one of below and equal to the maximum permitted spending limit control session. The method further comprises accepting, by the fourth NF, the spending limit control session request from the second NF, based on the determining that the count of the existing spending limit control sessions is below the maximum permitted spending limit control sessions. The method comprises transmitting, by the fourth NF, the acceptance response for the spending limit control session request, to the second NF.

[0023] In another exemplary aspect of the present disclosure, the method further comprises deleting, by the fourth NF, a spending limit control session from the existing spending limit control sessions, based on the determination that the count of the existing spending limit control sessions is equal to the maximum permitted spending limit control sessions. The deleting of the spending limit control session from the existing spending limit control sessions is based on a timestamp associated each of the spending limit control session from the existing spending limit control sessions. Also, the method comprises accepting, by the fourth NF, the spending limit control request, from the second NF. The method further comprises transmitting, by the fourth NF, the acceptance response for the spending limit control session request, to the second NF.

[0024] In another exemplary aspect of the present disclosure, the fourth NF is a Charging Function (CHF) in the network.

[0025] In another exemplary aspect of the present disclosure, the maximum permitted policy sessions, associated with the subset of attributes is received from a configurable table configured at the second NF.

[0026] In yet another exemplary aspect of the present disclosure, the method further comprises transmitting, by the first NF, to the fourth NF, a converged charging create request associated with the subset of attributes. The method comprises receiving, by the fourth NF, a maximum permitted PDU sessions for the subset of attributes. The method comprises receiving, by the fourth NF, a count of existing PDU sessions for the subset of attributes. The method further comprises determining, by the fourth NF, whether the count of the existing PDU sessions is one of below and equal to the maximum permitted PDU sessions. The method comprises accepting, by the fourth NF, the converged charging create request from the first NF, based on the determining that the count of the existing PDU sessions is below the maximum permitted PDU sessions. The method comprises transmitting, an acceptance response for the converged charging create request, to the first NF.

[0027] In another exemplary aspect of the present disclosure, the method further comprises deleting, by the fourth NF, a PDU session from the existing PDU sessions, based on the determining that the count of the existing PDU sessions is equal to the maximum permitted PDU sessions. The deleting of the PDU session from the existing PDU sessions is based on a timestamp associated with each of the PDU session from the existing PDU sessions. Further, the method comprises accepting, by the fourth NF, the charging service request, from the first NF. Also, the method comprises transmitting, an acceptance response for the converged charging create request, to the first NF.

[0028] Another aspect of the present disclosure may relate to a system for managing a Packet Data Unit (PDU) session establishment in a network. The system comprises a first transceiver unit, at a first network function (NF), configured to receive, the PDU session establishment request for a User Equipment (UE). The first transceiver unit is configured to transmit, from the first NF to a second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE. The system further comprises a second processing unit, at the second NF, configured to determine, one of a presence and an absence of an existing policy session associated with the set of attributes for the UE. Also, the system comprises a second transceiver unit, at the second NF, configured to receive maximum permitted policy sessions and a count of established policy sessions, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy session. Further, the second processing unit, at the second NF, is configured to determine, whether the count of established policy sessions is one of below and equal to the maximum permitted policy sessions associated with the subset of attributes. The system further comprises a second processing unit, at the second NF, configured to accept the PDU session establishment request for the UE, based on the determination that the count of established policy sessions is below the maximum permitted policy sessions.

[0029] In another exemplary aspect of the present disclosure, the second processing unit, at the second NF, is further configured to delete the existing policy session for the UE, in an event of the presence of the existing policy session for the UE and accept the PDU session establishment request from the UE.

[0030] In another exemplary aspect of the present disclosure, the second processing unit, at the second NF, is further configured to delete, a policy session from the established policy sessions, based on the determining that the count of established policy sessions is equal to the maximum permitted policy sessions.

[0031] In yet another exemplary aspect of the present disclosure, the deleting the policy session from the established policy sessions, is determined based on a timestamp associated with each of the policy session from the established policy sessions. [0032] In another exemplary aspect of the present disclosure, the set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID.

[0033] In another exemplary aspect of the present disclosure, the subset of attributes of the set of attributes comprises at least a SUPI, a DNN, and a network slice.

[0034] In another exemplary aspect of the present disclosure, the first NF is a Session Management Function (SMF) in the network.

[0035] In another exemplary aspect of the present disclosure, the second NF is a Policy Control Function (PCF) in the network.

[0036] In another exemplary aspect of the present disclosure, the system further comprises the second transceiver unit, at the second NF, that is configured to transmit, to a third NF, a management register request for the UE comprising the subset of attributes. Also, the system comprises a third transceiver unit, at the third NF, that is configured to receive, a maximum permitted binding sessions for the subset of attributes and receive, a count of existing binding sessions for the subset of attributes. The system comprises a third processing unit, at the third NF, configured to determine, whether the count of the existing binding sessions is one of below and equal to the maximum permitted binding sessions and accept, the management register request from the second NF, based on the determining that the count of the existing binding sessions is below the maximum permitted binding sessions. In addition, the system comprises the third transceiver unit, at the third NF, that is further configured to transmit, an acceptance response for the management register request, to the second NF.

[0037] In another exemplary aspect of the present disclosure, based on the determination that the count of the existing binding sessions is equal to the maximum permitted binding sessions, the third processing unit at the third NF, determines one of a rejected response and an acceptance response based on a flag value in a user configurable table.

[0038] In another exemplary aspect of the present disclosure, the rejected response is transmitted by the third transceiver unit, to the second NF, based on a true value of the flag in the user configurable table. [0039] In another exemplary aspect of the present disclosure, the acceptance response is transmitted by the third transceiver unit, to the second NF, based on a false value of the flag in the user configurable table.

[0040] In another exemplary aspect of the present disclosure, the acceptance response comprises deleting, by the third processing unit, at the third NF, a binding session from the existing binding sessions for the subset of attributes.

[0041] In another exemplary aspect of the present disclosure, the deleting of the binding session from the existing binding sessions is determined by the third processing unit, based on a timestamp associated with each binding session of the existing binding sessions.

[0042] In an exemplary aspect of the present disclosure, the third NF is a Binding Support Function (BSF) in the network.

[0043] In an exemplary aspect of the present disclosure, the system further comprises the second transceiver unit, at the second NF, configured to transmit, to a fourth NF, a spending limit control session request associated with the subset of attributes and a fourth transceiver unit, at the fourth NF, configured to receive, a maximum permitted spending limit control sessions for the combination of the subset of attributes. The fourth transceiver unit is further configured to receive, a count of existing spending limit control sessions for the subset of attributes. Also, the system includes a third processing unit, at the fourth NF, configured to determine, whether the count of the existing spending limit control sessions is one of below and equal to the maximum permitted spending limit control sessions and accept, the spending limit control session request from the second NF, based on the determining that the count of the existing spending limit control sessions is below the maximum permitted spending limit control sessions. Furthermore, the fourth transceiver unit, at the fourth NF, is configured to transmit, the acceptance response for the spending limit control session request, to the second NF.

[0044] In an exemplary aspect of the present disclosure, the system comprises the third processing unit, at the fourth NF, that is further configured to delete, a spending limit control session from the existing spending limit control sessions, based on the determining that the count of the existing spending limit control sessions is equal to the maximum permitted spending limit control sessions, wherein the deleting of the spending limit control session from the existing spending limit control sessions is based on a timestamp associated with each of the spending limit control session from the existing spending limit control sessions and accept, the spending limit control request, from the second NF. Also, the system comprises the fourth transceiver unit, at the fourth NF, that is further configured to transmit the acceptance response for the spending limit control session request, to the second NF.

[0045] In an exemplary aspect of the present disclosure, the fourth NF is a Charging Function (CHF) in the network.

[0046] In an exemplary aspect of the present disclosure, the maximum permitted policy control sessions, associated with the subset of attributes is received from a configurable table configured at the second NF.

[0047] In an exemplary aspect of the present disclosure, the system comprises the first transceiver unit, at the First NF, is further configured to transmit, to the fourth NF, a converged charging create request associated with the subset of attributes. The system comprises the fourth transceiver unit, at the fourth NF, that is further configured to: receive a maximum permitted PDU sessions for the subset of attributes, and a count of existing PDU sessions for the subset of attributes. Further, the system comprises the third processing unit, at the fourth NF, that is configured to determine, whether the count of the existing PDU sessions is one of below and equal to the maximum permitted PDU sessions, and accept, the converged charging create request from the first NF, based on the determining that the count of the existing PDU sessions is below the maximum permitted PDU sessions. Also, the system comprises the fourth transceiver unit, at the fourth NF, that is further configured to transmit an acceptance response for the converged charging create request, to the first NF.

[0048] In an exemplary aspect of the present disclosure, the third processing unit, at the fourth NF is further configured to delete a PDU session from the existing PDU sessions, based on the determination that the count of the existing PDU session is equal to the maximum permitted PDU session. Deleting the PDU session from the existing from the existing PDU sessions, is based on a timestamp associated with each of the PDU session from the existing PDU sessions. Further, the third processing unit is configured to accept, the charging service request, from the first NF; and the fourth transceiver unit, at the fourth NF, is further configured to transmit, an acceptance response for the converged charging create request, to the first NF.

[0049] Yet another aspect of the present disclosure may relate to a method for managing a Packet Data Unit (PDU) session establishment in a network is disclosed. The method comprises: receiving, by a network function (NF) service consumer, the PDU session establishment request for a User Equipment (UE); and connecting, by the first NF, to a second NF to process the PDU session establishment request for the UE. Further, the method comprises transmitting, by the first NF, to the second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE. The method comprises determining, by the second NF, one of a presence and an absence of an existing policy association, associated with the set of attributes for the UE. In addition, the method comprises identifying, by the second NF, a first timestamp associated with the existing policy association, based on determining the presence of the existing policy association. The method comprises identifying, by the second NF, a second timestamp associated with the policy control create request. The method comprises comparing, by the second NF, the first timestamp and the second timestamp. Also, the method comprises accepting, by the second NF, the policy control create request based on the comparing.

[0050] In an exemplary aspect of the present disclosure, comparing the first timestamp and the second timestamp comprises: determining, if the second timestamp is greater than the first timestamp.

[0051] In an exemplary aspect of the present disclosure, accepting the policy control request is based on determining that the second timestamp is greater than the first timestamp.

[0052] In an exemplary aspect of the present disclosure, accepting the policy control create request, comprises deleting, the existing policy association.

[0053] In an exemplary aspect of the present disclosure, the set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID.

[0054] In another exemplary aspect of the present disclosure, the method comprises receiving, by the second NF, a maximum permitted policy associations, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy association. The method further comprises determining, by the second NF, a count of existing associations, associated with the subset of attributes from the set of attributes. The method comprises rejecting, by the second NF, the policy control create request based on determining that the count of existing associations has reached the maximum permitted policy associations.

[0055] In an exemplary aspect of the present disclosure, the subset of attributes comprises at least the SUPI, a DNN, and a network slice. [0056] Yet another aspect of the present disclosure relates to a system for managing a Packet Data Unit (PDU) session establishment in a network. The system comprises a first transceiver unit, at a network function (NF) service consumer, configured to: receive the PDU session establishment request for a User Equipment (UE). In addition, the first transceiver unit is configured to connect to a second NF to process the PDU session establishment request from the UE. Also, the first transceiver unit is configured to transmit, to the second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE. The system comprises a second processing unit, at the second NF, configured to: determine one of a presence and an absence of an existing policy session associated with the set of attributes for the UE; and identify a first timestamp associated with the existing policy association, based on determining the presence of the existing policy association. The second processing unit is further configured to identify a second timestamp associated with the policy control create request; and compare the first timestamp with the second timestamp. Further, the second processing unit, at the second NF, is configured to accept the policy control create request based on the comparison of the first timestamp with the second timestamp.

[0057] In an exemplary aspect of the present disclosure, the second processing, upon the comparison of the first timestamp with the second timestamp, is further configured to determine if the second timestamp is greater than the first timestamp.

[0058] In an exemplary aspect of the present disclosure, the second processing unit is configured to accept the policy control request based on determining that the second timestamp is greater than the first timestamp.

[0059] In an exemplary aspect of the present disclosure, the second processing unit is further configured to delete the existing policy association.

[0060] In an exemplary aspect of the present disclosure, the set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID.

[0061] In an exemplary aspect of the present disclosure, the first transceiver unit is further configured to receive, by the second NF, a maximum permitted policy associations, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy association. Also, the first transceiver unit is configured to determine a count of existing associations, associated with the subset of attributes from the set of attributes; and reject the policy control create request based on determining that the count of existing associations has reached the maximum permitted policy associations.

[0062] In an exemplary aspect of the present disclosure, the subset of attributes comprises at least the SUPI, DNN, and the network slice.

[0063] Yet another aspect of the present disclosure may relate to a non-transitory computer-readable storage medium for managing a Packet Data Unit (PDU) session establishment in a network, the storage medium comprising executable code which, when executed by one or more units of a system, causes: a first transceiver unit, at a first network function (NF), configured to receive, the PDU session establishment request for a User Equipment (UE) and transmit, from the first NF, to a second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE. Further, the executable code which, when executed by the one or more units of the system, causes: a second processing unit, at the second NF, configured to determine, one of a presence and an absence of an existing policy session associated with the set of attributes for the UE; and a second transceiver unit, at the second NF, to receive, maximum permitted policy sessions and a count of established policy sessions, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy session. Further, the executable code which, when executed causes the second processing unit, at the second NF, to determine, whether the count of established policy sessions is one of below and equal to the maximum permitted policy sessions associated with the subset of attributes; and the second processing unit, to accept, the PDU session establishment request for the UE, based on the determination that the count of established policy sessions is below the maximum permitted policy sessions.

[0064] Yet another aspect of the present disclosure may relate to a non-transitory computer-readable storage medium storing instructions for managing a Packet Data Unit (PDU) session establishment in a network, the instructions comprising executable code which, when executed by one or more units of a system, causes: a first transceiver unit to receive the PDU session establishment request for a User Equipment (UE); connect to a second NF to process the PDU session establishment request from the UE; and transmit, to the second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE. Further, the executable code when executed by the one or more units of the system, causes a second processing unit to identify a first timestamp associated with the existing policy association, based on determining the presence of the existing policy association; to identify a second timestamp associated with the policy control create request; and to compare the first timestamp with the second timestamp. Also, the executable code when executed by the one or more units of the system, causes the second processing unit to accept the policy control create request based on the comparison of the first timestamp with the second timestamp.

OBJECTS OF THE INVENTION

[0065] Some of the objects of the present disclosure, which at least one embodiment disclosed herein satisfies are listed herein below.

[0066] It is an object of the present disclosure to provide a system and a method for managing a Packet Data Unit (PDU) session establishment in a network.

[0067] It is another object of the present disclosure to provide a solution to control an increase in a number of stale sessions which in turn results in saving the signalling traffic that is sent for validation of stale sessions.

[0068] It is another object of the present disclosure to provide a solution to remove the faulty devices or network components leading to creation of multiple sessions.

[0069] It is yet another object of the present disclosure to provide a solution that can optimize the resources (compute, memory and storage) used by Network Function (NF) by deleting or overwriting old sessions which are no longer live in network with assumption that devices in network have capabilities that are understood by service provider.

DESCRIPTION OF THE DRAWINGS

[0070] The accompanying drawings, which are incorporated herein, and constitute a part 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 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.

[0071] FIG. 1 illustrates an exemplary block diagram of a system for managing a Packet Data Unit (PDU) session establishment in a network, in accordance with exemplary embodiments of the present disclosure.

[0072] FIG. 2 illustrates an exemplary system architecture depicting various network elements for managing the PDU session establishment in the network, in accordance with exemplary implementation of the present disclosure.

[0073] FIG. 3A and FIG. 3B illustrate an exemplary process flow diagram of the system, in accordance with exemplary implementations of the present disclosure.

[0074] FIG. 4A and FIG. 4B illustrate another exemplary process flow diagram of the system, in accordance with exemplary implementations of the present disclosure.

[0075] FIG. 5 illustrates a method flow diagram for managing the Packet Data Unit (PDU) session establishment in the network, in accordance with exemplary implementations of the present disclosure.

[0076] FIG. 6 illustrates another method flow diagram for managing the Packet Data Unit (PDU) session establishment in the network, in accordance with exemplary implementations of the present disclosure

[0077] The foregoing shall be more apparent from the following more detailed description of the disclosure.

DETAILED DESCRIPTION

[0078] In the following description, for the purposes of explanation, various specific details are set forth 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 may not address any of the problems discussed above or might address only some of the problems discussed above. [0079] 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 spirit and scope of the disclosure as set forth.

[0080] 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, 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.

[0081] 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, 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.

[0082] 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 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 like the term “comprising” as an open transition word without precluding any additional or other elements.

[0083] 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 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 working of the system according to the present disclosure. More specifically, the processor or processing unit is a hardware processor.

[0084] 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 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 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.

[0085] 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 storage unit stores at least the data that may be required by one or more units of the system to perform their respective functions.

[0086] 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 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.

[0087] 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 controller, a microcontroller, Application Specific Integrated Circuits (ASIC), Field Programmable Gate Array circuits (FPGA), any other type of integrated circuits, etc.

[0088] As used herein the transceiver unit includes at least one receiver and at least one transmitter configured respectively for receiving and transmitting data, signals, information or a combination thereof between units/components within the system and/or connected with the system.

[0089] As discussed in the background section, the current known solutions have several shortcomings. Currently, 3GPP does not define any specific way to limit the number of sessions that can be created for individual subscribers. This may create problems when network fluctuations occur where multiple sessions (SM Policy Sessions or PDU Binding Sessions or Spending Limit Control) are created for an individual subscriber. Also, this may result in consuming all important resources of the NFs (PCF, BSF and CHF-PC) unnecessarily. Further, many of those created sessions would be stale sessions or non-live sessions which may also result in additional signalling traffic to be sent after stale session audit is done. The present disclosure aims to overcome the problems mentioned in the background section and other existing problems in this field of technology by providing method and system for managing a Packet Data Unit (PDU) session establishment in a network

[0090] FIG. 1 illustrates an exemplary block diagram of a system [100] for managing a Packet Data Unit (PDU) session establishment in a network, in accordance with exemplary embodiments of the present disclosure. The network may be a 5G core network, 6G core network and the like. As shown in FIG. 1, the system [100] includes a First NF (SMF) [204] comprising a first transceiver unit [102], a first processing unit [104 and a first storage unit [106], The system [100] further includes a Second NF (PCF) [216] comprising a second transceiver unit [108], a second processing unit [110], and a second storage unit [112], The system [100] further includes a Third NF (BSF) [208] comprising a third transceiver unit [114], a third processing unit [116] and a third storage unit [118], The system [100] further includes a Fourth NF (CHF) [206] comprising a fourth transceiver unit [120], a fourth processing unit [122] and a fourth storage unit [124], Further, the first storage unit [106] is associated with the first transceiver unit [102], The second storage unit [112] is associated with the second transceiver unit [108], The third storage unit [118] is associated with the third transceiver unit [114] and the fourth storage unit [124] is associated with the fourth transceiver unit [120], [0091] Further, the exemplary block diagram of the system [100] as shown in FIG. 1 is intended to be read in conjunction with an exemplary architecture [200] as shown in FIG. 2. The FIG. 1 and FIG. 2 complement each other.

[0092] It is to be noted that the number of transceiver units may not be limited to the mentioned number of units and may be more or less than four. It is to be noted that the number of the processing units may not be limited to the mentioned number of units and may be more or less than four. It is to be noted that the number of the storage units may not be limited to the mentioned number of units and may be more or less than four. All the components of the system [100] are assumed to be connected to each other in a manner as obvious to the person skilled in the art for implementing features of the present disclosure.

[0093] The first transceiver unit [102], at a first network function (NF), is configured to receive the PDU session establishment request for a User Equipment (UE). In general, PDU session establishment is a process of establishing a data path between the UE and the network. Further, a PDU session is a logical connection between the UE and the network, such as the internet or a private network. The PDU session is used to carry user data and may support different types of services, such as voice, video, and data. The PDU session establishment request may include information about the type of service that the UE wants to use, and a type of network traffic (such as real-time network traffic or non-real-time network traffic). Further, the first NF is a Session Management Function (SMF) [204] in the network. In general, the first NF/SMF [204] is a core network function responsible for managing session-related aspects, such as establishing, modifying, and releasing sessions. The SMF [204] coordinates with a User Plane Function (UPF) for data forwarding and handles IP address allocation and Quality of Service (QoS) enforcement. In an implementation, the first transceiver unit [102] is configured to connect with a second NF to process the PDU session establishment request from the UE.

[0094] Also, the first transceiver unit [102] is configured to transmit, from the first NF to the second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE. The policy control create request may be a request to create a new policy control session or update an existing one. The second NF is a Policy Control Function (PCF) [216] in the network. The PCF is responsible for policy control decisions and flow-based charging control functionalities. The second NF/PCF [216] provides policies for policies application and service data flow detection, gating, QoS, flow-based charging, traffic steering control, usage monitoring control, access traffic steering, switching and steering within a PDU Session, access network information report, Time Sensitive Networking (TSN) Bridge management Container (BMIC), TSN port management information container, TSN TSCAI input container and RAN support information to the SMF [204], Further, the SMF [204] facilitates enforcement of session management related policy decisions from the PCF [216], related to service flow detection, QoS, charging, gating, traffic usage reporting, traffic steering and access traffic steering, switching and splitting within a PDU Session. Further, when the second NF/PCF [216] accepts the policy control create request from the first NF/SMF [204], the related policy rules associated with the UE are processed by the first processing unit [104] at the first NF/SMF [204] and stored in the first storage unit [106],

[0095] The second transceiver unit [108], at the second NF, is configured to receive the PDU session establishment request from the first NF. The second transceiver unit [108] may be associated with the second processing unit [110], The second processing unit [110] at the second NF, is configured to determine one of a presence and an absence of an existing policy session associated with the set of attributes for the UE. In an embodiment, information associated with the presence and the absence of the existing policy session may be stored in the second storage unit [112], Further, any information associated with the second transceiver unit [108] may be stored in the second storage unit [112], The set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID. In general, SUPI is a unique identifier used to represent a subscriber's permanent identity in a 5G network. SUPI replaces the International Mobile Subscriber Identity (IMSI) used in 4G networks and is designed to provide enhanced privacy and security features. Further, the DNN is the counterpart of Access Point Name (APN) in LTE. The DNN is used to identify and route traffic to a specific network slice, which can be customized with specific QoS requirements for different services and applications. The network slice is a logical network that provides specific network capabilities and network characteristics, supporting various service properties for network slice customers or users. Further, the PDU Session ID is an identifier used to uniquely identify one of a UE's PDU Sessions.

[0096] Further, the second transceiver unit [108], at the second NF, is configured to receive maximum permitted policy sessions and a count of established policy sessions, associated with a subset of attributes from the set of attributes in an event of the absence of the existing policy session. The maximum permitted policy sessions refer to the maximum number of policy sessions that can be active. The second processing unit [110] is further configured to determine whether the count of established policy sessions is one of below and equal to the maximum permitted policy sessions associated with the subset of attributes. The subset of attributes of the set of attributes comprises at least the SUPI, the DNN, and the network slice. [0097] Further, the second processing unit [110] may be associated with the second processing unit [110], The second processing unit [110] at the second NF, is configured to accept the PDU session establishment request for the UE, based on the determination that the count of established policy sessions is below the maximum permitted policy sessions. Further, in one implementation, the second processing unit [110] at the second NF, is configured to delete the existing policy session for the UE, in an event of the presence of the existing policy session for the UE and accept the PDU session establishment request.

[0098] The second processing unit [110] is further configured to delete a policy session from the established policy sessions, based on the determination that the count of established policy sessions is equal to the maximum permitted policy sessions. The deleting of the policy session from the established policy sessions, is determined or performed based on a timestamp associated with each of the policy session from the established policy sessions.

[0099] In an alternative embodiment, the second processing unit [110] at the second NF is configured to determine one of a presence and an absence of an existing policy association, associated with the set of attributes for the UE. The second processing unit [110] is further configured to identify a first timestamp associated with the existing policy association, based on determination of the presence of the existing policy association. In addition, the second processing unit [110] is configured to identify a second timestamp associated with the policy control create request. Further, the second processing unit [110] is configured to compare the first timestamp with the second timestamp. In an embodiment, the second processing unit [110] may be configured to accept the policy control create request based on the comparison of the first timestamp with the second timestamp. The second processing unit [110], upon the comparison of the first timestamp with the second timestamp, is further configured to determine if the second timestamp is greater than the first timestamp. The second processing unit [110] is configured to accept the policy control request based on determining that the second timestamp is greater than the first timestamp.

[0100] In an alternative embodiment, the second transceiver unit [108] is further configured to receive, by the second NF, a maximum permitted policy associations, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy association. Also, the second processing unit [110] is configured to determine a count of existing associations, associated with the subset of attributes from the set of attributes; and reject the policy control create request based on determining that the count of existing associations has reached the maximum permitted policy associations. During the PDU session establishment, the second NF/PCF [216] may receive information from a Unified Data Repository (UDR) about the maximum permitted policy associations such as total allowed usage per DNN / S-NSSAI combination and the UE, i.e. the overall amount of allowed traffic volume and/or time of usage that are to be monitored per DNN / S-NSSAI combination and UE and/or the total allowed usage for Monitoring key(s) per DNN / S-NSSAI combination and UE. S-NSSAI refers to Single - Network Slice Selection Assistance Information. S-NSSAI is sent to the network by the UE to assist the network in selecting a particular network slice.

[0101] Referring again to the second transceiver unit [108], at the second NF, is further configured to transmit a management register request to a third NF, for the UE comprising the subset of attributes. The third NF is a Binding Support Function (BSF) [208] in the network. The third NF/BSF [208] enables policy/charging (PCF/CHF) scaling of the 5G network while ensuring session correlation for Hyper Text Transfer Protocol (HTTP). The BSF is configured to track sessions that are located anywhere in the network, but share common criteria, such as subscriber identifiers. The third NF/BSF [208] enables correlation of sessions across multiple policy servers. In general, the third NF/BSF [208] is configured to find binding information such as address information of a selected second NF/PCF [216], then allow the second NF/PCF [216]to register, update and remove the binding information and allows Application Function (AF) or Network Exposure Function (NEF) to discover the binding information. Further, the NEF is a function that facilitates secure, robust, developer-friendly access to exposed network services and provides customers capabilities that are provided by 3GPP 5G network functions. The exposure may be an internal exposure or re-exposure. In general, the NEF may be connected to network ecosystems since its applications are data-rich and resourceful. This means that access to network data and resources for different ecosystems is enriched with enterprise applications. Data transportation within signalling messages is enabled by the NEF via a control plane which eliminates user plane connection which is costly.

[0102] The second transceiver unit [108] may be associated with the third transceiver unit [114], The third transceiver unit [114], at the third NF, is configured to receive, a maximum permitted binding sessions for the subset of attributes and to receive, a count of existing binding sessions for the subset of attributes. The third transceiver unit [114] may be associated with the third processing unit [116], Further, the third processing unit [116] is configured to determine whether the count of the existing binding sessions is one of below and equal to the maximum permitted binding sessions. In general, the maximum permitted binding sessions refer to maximum number of simultaneous bindings or associations that a network entity allows with other entities. Also, the third processing unit [116] is configured to accept, the management register request from the second NF, based on the determination that the count of the existing binding sessions is below the maximum permitted binding sessions. The management register request may be a request to register or deregister a UE/user with the network and establish the user context in the network.

[0103] In addition, the third transceiver unit [114], at the third NF, is further configured to transmit, an acceptance response for the management register request, to the second NF. Based on the determination that the count of the existing binding sessions is equal to the maximum permitted binding sessions, the third processing unit [116] at the third NF, determines one of the rejected response and the acceptance response based on a flag value in a user configurable table. Generally, flag value is a binary indicator (often represented as a boolean or integer) that signifies presence or absence of a particular condition or setting. In addition, flag value in a user configurable table refers to a specific data structure or setting within a table that allows users or administrators to configure or control certain behaviours, options, or conditions within the system [100], The rejected response is transmitted by the third transceiver unit [114], to the second NF, based on a true value of the flag in the user configurable table. Further, the acceptance response is transmitted by the third transceiver unit [114], to the second NF, based on a false value of the flag in the user configurable table. The acceptance response comprises deleting, by the third processing unit [116], at the third NF, a binding session from the existing binding sessions for the subset of attributes. The deleting of the binding session from the existing binding sessions is determined by the third processing unit [116], based on a timestamp associated with each binding session of the existing binding sessions. In an embodiment, the acceptance response and the rejected response is stored in the third storage unit [118], Further, any information associated with the third transceiver unit [114] may be stored in the third storage unit [118],

[0104] The second transceiver unit [108], at the second NF, is configured to transmit to a fourth NF, a spending limit control session request associated with the subset of attributes. The second transceiver unit [108] and the third transceiver unit [114] may be associated with the fourth transceiver unit [120], The fourth transceiver unit [120], at a fourth NF, is configured to receive a maximum permitted spending limit control sessions for the subset of attributes and a count of existing spending limit control sessions for the subset of attributes. The fourth NF is a Charging Function (CHF) [206] in the network. The fourth NF/CHF [206] acts as a gateway into a charging system, supporting both session-based charging and event-based charging scenarios, with or without unit reservation, including new 5G capabilities such as network slicing.

[0105] The fourth transceiver unit [120] may be associated with the fourth processing unit [122], The fourth processing unit [122], at the fourth NF, is configured to delete, a spending limit control session from the existing spending limit control sessions, based on the determination that the count of the existing spending limit control sessions is equal to the maximum permitted spending limit control sessions. The deleting of the spending limit control session from the existing spending limit control sessions is based on a timestamp associated with each of the spending limit control session from the existing spending limit control sessions. In general, timestamp is a digital record of the time at which an event occurred. The fourth processing unit [122] is further configured to accept the spending limit control request, from the second NF. The fourth transceiver unit [120], at the fourth NF, is further configured to transmit, the acceptance response for the spending limit control session request, to the second NF. The maximum permitted policy control sessions, associated with the subset of attributes are received from a configurable table configured at the second NF. The spending limit control request enables the First NF to retrieve policy counter status information. In an embodiment, any information related to the spending limit control session may be stored in the fourth storage unit [124], Further, any information associated with the fourth transceiver unit [120] may be stored in the fourth storage unit [124],

[0106] Referring to the first transceiver unit [ 102], at the first NF, that is further configured to transmit to the fourth NF, a converged charging create request associated with the subset of attributes. The fourth transceiver unit [120], at the fourth NF, is further configured to receive, a maximum permitted PDU sessions for the subset of attributes and a count of existing PDU sessions for the subset of attributes from the fourth storage unit [124], In addition, the fourth processing unit [122], at the fourth NF, determines, whether the count of the existing PDU sessions is one of below and equal to the maximum permitted PDU sessions. Further, the fourth processing unit [122] accepts the converged charging create request from the first NF, based on the determination that the count of the existing PDU sessions is below the maximum permitted PDU sessions. Furthermore, the fourth transceiver unit [120], at the fourth NF, is further configured to transmit an acceptance response for the converged charging create request, to the first NF. The converged charging create request is the request that enables creation of a resource for charging. [0107] The fourth processing unit [122] at the fourth NF, is further configured to delete a PDU session from the existing PDU sessions, based on the determination that the count of the existing PDU sessions is equal to the maximum permitted PDU sessions. The deleting of the PDU session from the existing PDU sessions, is based on a timestamp associated with each of the PDU session from the existing PDU sessions. In general, timestamp indicates the time of initiation or last modification. The timestamp helps in tracking the age or relevance of the PDU session. Further, the fourth processing unit [122] is further configured to accept the charging service request, from the first NF. Lastly, the fourth transceiver unit [120], at the fourth NF, transmits an acceptance response for the converged charging create request to the first NF. The converged charging create request refers to a process by which charging information is managed and processed.

[0108] In an example, upon receipt of a Npcf SMPolicyControl Create service request which collides with an existing “SM Policy Association” for the same UE (i.e. same values of "supi" attribute) and the same PDU session Id (i.e. same values of "pduSessionld" attribute), the PCF [216] may accept the new request only if it contains a more recent timestamp within 3gpp- Sbi-Origination-Timestamp header than the origination timestamp stored for the existing SM Policy Association. In an alternate embodiment, an incoming “Npcf SMPolicyControl Create” service request shall be considered as more recent than an existing SM Policy Association and be accepted if no 3gpp-Sbi-Origination-Timestamp header is provided for at least one of the two SM Policy Associations. The Npcf SMPolicyControl Create service request is a request to create an SM Policy Association with the PCF to receive a policy for a PDU session. The SM Policy Association refers to a process of associating policy rules and parameters with session management procedures within the network. The "supi" attribute stands for Subscription Permanent Identifier and is a globally unique identifier assigned to each subscriber in the network. It is intended to uniquely identify a subscriber across different network functions and systems. Further, the “pduSessionld” is an identifier encoded within protocol messages exchanged between a UE and 5G Core Network elements, ensuring accurate and efficient session management. The “pduSessionlD” is used to route data packets associated with a specific PDU Session through appropriate network paths and functions. Also, 3gpp-Sbi-Origination- Timestamp is a header containing a timestamp that indicates a time at which a signalling message was originated within the network.

[0109] Further, an exemplary architecture of the system [100] is explained in FIG. 2. [0110] FIG. 2 illustrates an exemplary architecture [200] of the system [100] depicting various network elements for managing the PDU session establishment in the network, in accordance with exemplary implementation of the present disclosure. The various network elements include but may not be limited to a Session Management Function (SMF) [204], a Charging Function (CHF) [206], a Binding Support Function (BSF) [208], a Network Repository Function (NRF) [210], an Access and Mobility Management Function (AMF) [212], a Policy Control Function (PCF) [216], and an Application Function (AF) [220], The architecture [200] includes all the mentioned network elements, a Deep Packet Inspection unit (DPI) [202] and one or more reference points such as Sd [222], N7 [224], N28 [226], Nbsf [228] and Nnrf [230], The DPI [202] provides network visibility and facilitates analysing and managing network traffic and securing networks in real-time.

[0111] The SMF [204] is similar to the first NF explained in FIG. 1.

[0112] The SMF [204] is configured to facilitate enforcement of session management related policy decisions from the PCF [216], related to service flow detection, QoS, charging, gating, traffic usage reporting, traffic steering and access traffic steering, switching and splitting within a PDU Session. The SMF [204] is configured to send the PDU session related set of attributes to the PCF [216] and request and receive the PCC rule(s) from the PCF [216], Also, the SMF [204] is configured to provide binding of service data flows to QoS flow. In addition, the SMF [204] is configured to derive rule(s) from the PCC rule(s) and then provide those rules to a user plane function (UPF) or remove the rule(s) from the user plane. The PCC rule is a set of information elements enabling detection of a service data flow and providing parameters for policy control and/or charging control.

[0113] In an embodiment, the PCC rules include dynamic PCC rules and pre-defined PCC rules. In general, the dynamic PCC rules are the PCC rules that are dynamically provisioned by the PCF [216] to the SMF [204], The dynamic PCC rules may be either predefined or dynamically generated in the PCF [216], The dynamic PCC rules can be installed, modified and removed at any time. The predefined PCC rules are the PCC rules that are preconfigured in the SMF [204], The predefined PCC rules may be activated or deactivated by the PCF [216] at any time. The predefined PCC rules within the PCF [216] may be grouped allowing the PCF [216] to dynamically activate a set of the PCC rules.

[0114] Further, the CHF [206] is similar to the fourth network function as explained in FIG. 1. Hence, its description is not repeated here. Further, the BSF [208] is similar to the third NF as explained in FIG. 1. Hence, its description is not repeated here. Also, the PCF [216] is similar to the second NF as explained in FIG. 1.

[0115] When the PCF [216] receives the HTTP POST request from the first NF or the SMF

[204], the PCF [216] makes a policy authorization based on the information received from the first NF or the SMF [204] and if available, information received from the AMF [212], the CHF [206], the AF [220], and operator policies pre-configured at the PCF [216], If the policy authorization is successful, the PCF [216] may create a new resource, which represents a new "Individual SM Policy" instance, addressed by a URI and containing a PCF created resource identifier. The PCF [216] may respond to the first NF with an HTTP 201 Created response, including a location header field containing the URI of the created resource and a response body providing the session management policies, such as provisioning of the PCC rules as and provisioning of policy control request triggers. The HTTP 201 Created response is a standard response code indicating that a request has been successfully fulfilled, and as a result, a new resource has been created. The first NF may use the URI received in the location header in subsequent requests to the PCF [216] to refer to the created "Individual SM Policy" resource.

[0116] Further, the Access and Mobility Management Function (AMF) [212] 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. The AF [220] is a network function that represents external applications interfacing with the 5G core network to access network capabilities and services.

[0117] In addition, the Network Repository Function (NRF) [210] 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. The AMF [212] may utilize the NRF [210] to discover SMF instances unless SMF [204] information is available by other means such as locally configured on the AMF [212], The NRF [210] provides IP address of the SMF instances to the AMF [212],

[0118] Further, all the network elements interact with the PCF [216] via the one or more reference points [222, 224, 226, 228 and 230], For example, in FIG. 2., the DPI unit [202] interacts with the PCF [216] via a reference point Sd [222], The SMF [204] interacts with the PCF [216] via a reference point N7 [224], Therefore, N7 is a reference point between the SMF [204] and the PCF [216], In addition, N7 may be an interface to trigger session management policies towards the Session Management Function (SMF) [204], Further, the reference point N28 enables interaction between the CHF [206] and the PCF [216], The reference point Nbsf [228] enables interaction between the BSF [208] and the PCF [216], Also, the reference point Nnrf [230] enables interaction between the NRF [210] and the PCF [218], The PCF [216] interacts with the AMF [212] via the reference point N15 [214], Also, the PCF interacts with the AF [220] through the reference point Rx [218], These reference points may act as an interface between the two units in communication.

[0119] FIG. 3A illustrates an exemplary process flow diagram [300A] of the system [100], in accordance with exemplary implementations of the present disclosure. The exemplary process flow diagram [300 A] depicts communication between the SMF [204] and the PCF [216], The SMF [204] sends a Npcf SMPolicyControl Create request to the PCF [216], The Npcf SMPolicyControl Create request relates to SM Policy Association enabling Time Sensitive Communications, Time Synchronization, and/or Deterministic Networking. In general, Deterministic Networking is a network technology approach that aims to provide predictable and reliable delivery of data packets within a network, especially in critical infrastructure environments where latency, jitter (variation in latency), and packet loss must be minimized and controlled.

[0120] The PCF [216] then may provide within an “SmPolicyDecision” data structure, a "TSN BRIDGE INFO" policy control request trigger within a "policyCtrlReqTriggers" attribute to instruct the SMF [204] to trigger a PCF interaction when the trigger is met, i.e., new TSC user plane node information (e.g. TSN Bridge) is available. The “SmPolicyDecision” includes the SM policies authorized by the PCF. Also, “TSN BRIDGE INFO” refers to information related to TSN Bridges within a TSN network. The “policyCtrlReqTriggers” defines the policy control request triggers subscribed by the PCF. TSN Bridge refers to a network device or entity that plays a critical role in enabling TSN capabilities within the network.

[0121] When an Npcf SMPolicyControl Create request is received, the PCF may check if the S-NSSAI to which the received request relates is subject to network slice data rate policy control. If it is the case, the PCF [216] may apply network slice data rate control. Also, the PCF [216] checks combination of defined parameter and accepts the session. If needed, the PCF [216] removes the existing sessions that has become old or inactive silently. Further, silent removal of the existing sessions means that the PCF [216] deletes the existing sessions without informing other connected NFs. In an embodiment, the PCF [216] maintains two timestamps: a creation timestamp and a last refreshed timestamp. When the PCF [216] receives a new create request and the maximum session limit per SUPI exceeds the defined threshold, it becomes imperative to prevent denial of service to users. In this scenario, removing the oldest session, which might be stale as it is not being updated, helps maintain performance of the system [100] and resource allocation.

[0122] Further, when the PCF [216] receives the Npcf SMPolicyControl Create request and a "NetSliceUsageCtrl" feature is supported, the PCF [216] may check whether the S-NSSAI to which the received request relates is subject to network slice usage control. The “NetSliceUsageCtrl” indicates support of the network slice usage control functionality. If it is the case, the PCF may provision in the Npcf SMPolicyControl Create response the network slice usage control information (e.g., the slice PDU session inactivity timer value) within the "sliceUsgCtrllnfo" attribute of the “SmPolicyDecision” data structure. The “sliceUsgCtrllnfo” represents slice usage control information (e.g., slice PDU Session inactivity timer value) to be used to support and enforce network slice usage control. The PCF [216] may respond to the SMF [204] with an HTTP 201 Created response, including a location header field containing the URI of the created resource, and a response body providing the session management related policies, such as provisioning of the PCC rules and provisioning of policy control request triggers.

[0123] If user information received within the "supi" attribute is unknown, the PCF [216] may reject the request with an HTTP "400 Bad Request" response message including the "cause" attribute of the “ProblemDetails” data structure set to "USER UNKNOWN". The HTTP 400 Bad Request is a standard response code indicating that a request has been rejected. The “cause” attribute defines the cause of rejection of the request. Also, “ProblemDetails” include information associated with rejection of the request.

[0124] If the PCF [216] is not able, to provision a policy decision in response to the request for PCC rules from the First NF due to incomplete, erroneous or missing information (e.g. QoS, RAT type, subscriber information), the PCF [216] may reject the request with an HTTP "400 Bad Request" response message including the "cause" attribute of the “ProblemDetails” data structure set to "ERROR INITIAL PARAMETERS". "ERROR INITIAL PARAMETERS" is a standard code that describes parameters due to which the request is rejected.

[0125] If the SMF [204]/ the First NF receives an HTTP response with the above error codes, the SMF [204]/the First NF shall reject the PDU session establishment request that initiated the HTTP POST Request. [0126] If the PCF [216], based on local configuration and/or operator policies, denies the creation of the Individual SM Policy resource, the PCF [216] may reject the request with an HTTP "403 Forbidden" response message including the "cause" attribute of the “ProblemDetails” data structure set to "POLICY CONTEXT DENIED" which means the HTTP request is rejected because the PCF does not accept the First NF request due to operator policies and/or local configuration. At reception of this error code and based on configured failure actions, the First NF may reject or allow, by applying local policies, the PDU session establishment.

[0127] FIG. 3B illustrates an exemplary process flow diagram [300B] of the system [100], in accordance with exemplary implementations of the present disclosure. The exemplary process flow diagram [300B] depicts communication between the PCF [216] and the BSF [208], The PCF [216] sends a “Nbsf Management Register” request to the BSF [208], The “Nbsf Management Register” request enables the PCF to register the session binding information for a User Equipment (UE) in the BSF. The BSF checks combination of defined parameter and accepts the session. If required, the existing sessions are silently removed by the BSF [208], Further, silent removal of the existing sessions means that the BSF [208] deletes the existing sessions without informing other connected NFs. Further, the BSF [208] may respond to the PCF [214] with an HTTP 201 Created response.

[0128] FIG. 4A illustrates another exemplary process flow diagram [400A] of the system [100], in accordance with exemplary implementations of the present disclosure. The process flow diagram [400 A] shows interaction between the SMF [204] and the CHF [206],

[0129] The SMF [204] sends an “Nchf ConvergedCharging Create” request to the CHF [206], The “Nchf ConvergedCharging Create” request is a request to enable transfer of policy counter status information relating to subscriber spending limits from the CHF [206] to the SMF [204], Further, the CHF [206] checks combination of defined parameter and accepts the session. If needed, the CHF [206] silently removes the existing sessions that has become old or inactive. Further, silent removal of the existing sessions means that the CHF [206] deletes the existing sessions without informing other connected NFs. Further, the CHF [206] respond to the SMF [204] with an HTTP 201 Created response.

[0130] FIG. 4B illustrates another exemplary process flow diagram [400B] of the system [100], in accordance with exemplary implementations of the present disclosure. The process flow diagram [400B] shows interaction between the PCF [216] and the CHF [206], The PCF [216] sends an “Nchf SpendingLimitControl Initial” request to the CHF [206], The CHF [206] may check for the combination of defined parameters and accepts the session. If needed, the CHF [206] may silently remove or delete the existing sessions that has become old or inactive. The “Nchf SpendingLimitControl Initial” request enables the PCF to retrieve policy counter status information per UE from the CHF by subscribing to spending limit reporting (i.e. notifications of policy counter status changes).

[0131] FIG. 5 illustrates a method flow diagram for managing the Packet Data Unit (PDU) session establishment in the network, in accordance with exemplary implementations of the present disclosure.

[0132] The method [500] initiates at step [502],

[0133] At step [504], the method [500] includes receiving, by the network function (NF) service consumer, the PDU session establishment request for the User Equipment (UE).

[0134] At step [506], the method [500] includes transmitting, from the first NF to the second NF, the policy control create request comprising the set of attributes associated with the PDU session establishment request for the UE. The first NF is a Session Management Function (SMF) [204] in the network.

[0135] At step [508], the method [500] includes determining, by the second NF, one of a presence and an absence of the existing policy session associated with the set of attributes for the UE. The set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID.

[0136] At step [510], the method [500] includes receiving, by the second NF, maximum permitted policy sessions and the count of established policy sessions, associated with the subset of attributes from the set of attributes, in the event of the absence of the existing policy session.

[0137] At step [512], the method [500] includes determining, by the second NF, whether the count of established policy control sessions is one of below and equal to the maximum permitted policy sessions associated with the subset of attributes.

[0138] At step [514], the method [500] includes accepting, by the second NF, the PDU session establishment request from the UE, based on the determination that the count of established policy sessions is below the maximum permitted policy sessions. [0139] The method [500] further includes deleting, by the second NF, the existing policy session for the UE, in an event of the presence of the existing policy session for the UE and accepting the PDU session establishment request from the UE.

[0140] Also, the method [500] further comprises, deleting, by the second NF, a policy session from the established policy sessions, based on the determination that the count of established policy sessions is equal to the maximum permitted policy sessions. The deleting the policy session from the established policy sessions, is determined based on a timestamp associated with each of the policy session from the established policy sessions.

[0141] The method [500] further comprises, transmitting, by the second NF, to a third NF, a management register request for the UE comprising the subset of attributes, the third NF is a Binding Support Function (BSF) [208] in the network. Also, the method [500] includes receiving, by the third NF, a maximum permitted binding sessions and a count of existing binding sessions for the subset of attributes. The method further includes determining, by the third NF, whether the count of the existing binding sessions is one of below and equal to the maximum permitted binding sessions. The method [500] includes accepting, by the third NF, the management register request from the second NF, based on the determining that the count of the existing binding sessions is below the maximum permitted binding sessions. Then, the method [500] includes transmitting, by the third NF, an acceptance response for the management register request, to the second NF. The acceptance response is transmitted to the second NF, based on a false value of the flag in a user configurable table.

[0142] The method [500], further comprises, based on the determination that the count of the existing binding sessions is equal to the maximum permitted binding sessions, the third NF, determines one of a rejected response and an acceptance response based on a flag value in a user configurable table. The rejected response is transmitted to the second NF, based on a true value of the flag in the user configurable table. The acceptance response comprises deleting a binding session of the existing binding sessions for the subset of attributes. Deleting the binding session from the existing binding sessions is determined based on a timestamp associated with each binding session of the existing binding sessions.

[0143] The method [500] includes transmitting, by the second NF, to a fourth NF, a spending limit control session request associated with the subset of attributes. The fourth NF is a Charging Function (CHF) [206] in the network. The method [500] includes receiving, by the fourth NF, a maximum permitted spending limit control sessions for the subset of attributes. Also, the method [500] includes receiving, by the fourth NF, a count of existing spending limit control sessions for the subset of attributes.

[0144] The method [500] further includes determining, by the fourth NF, whether the count of the existing spending limit control sessions is one of below and equal to the maximum permitted spending limit control sessions; accepting, by the fourth NF, the spending limit control session request from the second NF, based on the determining that the count of the existing spending limit control sessions is below the maximum permitted spending limit control sessions; and transmitting, by the fourth NF, the acceptance response for the spending limit control session request, to the second NF.

[0145] The method [500] further includes deleting, by the fourth NF, a spending limit control session from the existing spending limit control sessions, based on the determination that the count of the existing spending limit control sessions is equal to the maximum permitted spending limit control sessions, wherein deleting the spending limit control session from the existing spending limit control sessions is based on a timestamp associated each of the spending limit control session from the existing spending limit control sessions. The method [500] includes accepting, by the fourth NF, the spending limit control request, from the second NF. The method [500] includes transmitting, by the fourth NF, the acceptance response for the spending limit control session request, to the second NF. The maximum permitted policy sessions, associated with the subset of attributes is received from a configurable table configured at the second NF.

[0146] The method [500] further includes transmitting, by the first NF, to the fourth NF, a converged charging create request associated with the subset of attributes; receiving, by the fourth NF, a maximum permitted PDU sessions for the subset of attributes; receiving, by the fourth NF, a count of existing PDU sessions for the subset of attributes; determining, by the fourth NF, whether the count of the existing PDU sessions is one of below and equal to the maximum permitted PDU sessions; accepting, by the fourth NF, the converged charging create request from the first NF, based on the determining that the count of the existing PDU sessions is below the maximum permitted PDU sessions; and transmitting, an acceptance response for the converged charging create request, to the first NF.

[0147] The method [500] further includes deleting, by the fourth NF, a PDU session from the existing PDU sessions, based on the determining that the count of the existing PDU sessions is equal to the maximum permitted PDU sessions, wherein deleting of the PDU session from the existing PDU sessions is based on a timestamp associated with each of the PDU session from the existing PDU sessions; accepting, by the fourth NF, the charging service request, from the first NF; and transmitting, an acceptance response for the converged charging create request, to the NF service consume.

[0148] Thereafter, the method [500] terminates at step [516],

[0149] FIG. 6 illustrates another method flow diagram for managing the Packet Data Unit (PDU) session establishment in the network, in accordance with alternative implementations of the present disclosure.

[0150] The method [600] initiates at step [602],

[0151] At step [604], the method [600] includes receiving, by a network function (NF) service consumer, a PDU session establishment request for a User Equipment (UE). The first NF is a Session Management Function (SMF) [204] in the network (as explained in FIG. 1). In general, the Session Management Function (SMF) [204] is a core network function responsible for managing session-related aspects, such as establishing, modifying, and releasing sessions. The SMF [204] coordinates with a User Plane Function (UPF) for data forwarding and handles IP address allocation and Quality of Service (QoS) enforcement. In an implementation, the first transceiver unit [102] is configured to connect to a second NF to process the PDU session establishment request from the UE.

[0152] At step [606], the method [600] includes connecting, by the first NF, to a second NF, to process the PDU session establishment request for the UE. The second NF is the Policy Control Function in the network. The PCF [216] is responsible for policy control decisions and flow-based charging control functionalities. The PCF [216] provides policies for policy application and service data flow detection, gating, QoS, flow-based charging, traffic steering control, usage monitoring control, access traffic steering, switching and steering within a PDU Session, access network information report, and RAN support information to the SMF. Further, the SMF facilitates enforcement of session management related policy decisions from the PCF [216], related to service flow detection, QoS, charging, gating, traffic usage reporting, traffic steering and access traffic steering, switching and splitting within the PDU session.

[0153] At step [608], the method [600] includes transmitting, by the first NF or the SMF [204], to the second NF, the policy control create request comprising the set of attributes associated with the PDU session establishment request for the UE. The policy control create request may be a request to create a new policy control session or update an existing one. Further, the SMF [204] facilitates enforcement of session management related policy decisions from the PCF [216], related to service flow detection, QoS, charging, gating, traffic usage reporting, traffic steering and access traffic steering, switching and splitting within a PDU Session. The SMF [204] is configured to send the PDU session related set of attributes to the PCF [216] and request and receive the PCC rule(s) from the PCF [216], Also, the SMF [204] is configured to provide binding of service data flows to QoS flow. In addition, the SMF [204] is configured to derive rule(s) from the PCC rule(s) and then provide those rules to a user plane function (UPF) or remove the rule(s) from the user plane. The PCC rule is a set of information elements enabling detection of a service data flow and providing parameters for policy control and/or charging control.

[0154] In an embodiment, the PCC rules include dynamic PCC rules and pre-defined PCC rules. In general, the dynamic PCC rules are the PCC rules that are dynamically provisioned by the PCF [216] to the SMF [204], The dynamic PCC rules may be either predefined or dynamically generated in the PCF [216], The dynamic PCC rules can be installed, modified and removed at any time. The predefined PCC rules are the PCC rules that are preconfigured in the SMF [204], The predefined PCC rules may be activated or deactivated by the PCF [216] at any time. The predefined PCC rules within the PCF [216] may be grouped allowing the PCF [216] to dynamically activate a set of the PCC rules.

[0155] At step [610], the method [600] includes determining, by the second NF, one of a presence and an absence of the existing policy association, associated with the set of attributes for the UE. The set of attributes comprises ae Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID. In general, SUPI is a unique identifier used to represent a subscriber's permanent identity in a 5G network. SUPI replaces the International Mobile Subscriber Identity (IMSI) used in 4G networks and is designed to provide enhanced privacy and security features. Further, the DNN is the counterpart of Access Point Name (APN) in LTE. The DNN is used to identify and route traffic to a specific network slice, which can be customized with specific QoS requirements for different services and applications.

[0156] At step [612], the method [600] includes identifying, by the second NF, a first timestamp associated with the existing policy association, based on determining the presence of the existing policy association. [0157] At step [614], the method [600] includes identifying, by the second NF, a second timestamp associated with the policy control create request.

[0158] At step [616], the method [600] includes comparing, by the second NF, the first timestamp and the second timestamp. The comparing the first timestamp and the second timestamp comprises determining if the second timestamp is greater than or recent than the first timestamp. For example, upon receipt of a “Npcf SMPolicyControl Create” service request which collides with an existing SM Policy, association for the same UE (i.e. same values of "supi" attribute) and the same PDU session Id (i.e. same values of "pduSessionld" attribute), the PCF [216] may accept the new request only if it contains a more recent timestamp within the 3gpp-Sbi-Origination-Timestamp header than the origination timestamp stored for the existing SM Policy Association. In an alternate embodiment, an incoming “Npcf SMPolicyControl Create” service request shall be considered as more recent than an existing SM Policy Association and be accepted if no 3gpp-Sbi-Origination-Timestamp header is provided for at least one of the two SM Policy Associations.

[0159] At step [618], the method [600] includes accepting, by the second NF, the policy control create request based on the comparing. The accepting the policy control request is based on determining that the second timestamp is greater than the first timestamp. Further, the accepting the policy control request comprises deleting the existing policy association.

[0160] In an alternate embodiment, the method [600] includes that the PCF [216] may reject an incoming request whose timestamp is less recent than the timestamp of the existing SM Policy Association with the HTTP status code "403 Forbidden" and the application error "LATE OVERLAPPING REQUEST". The HTTP status code “403 Forbidden” and the application error “LATE OVERLAPPING REQUEST” depicts that the request is rejected because it collides with an existing policy association with a more recent originating timestamp.

[0161] The method [600] further comprises receiving, by the second NF, maximum permitted policy associations, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy association. During the PDU session establishment, the PCF [216] may receive information from a Unified Data Repository (UDR) about the maximum permitted policy associations such as total the allowed usage per DNN / S-NSSAI combination and the UE, i.e. the overall amount of allowed traffic volume and/or time of usage that are to be monitored per DNN / S-NSSAI combination and UE and/or the total allowed usage for Monitoring key(s) per DNN / S-NSSAI combination and UE. [0162] The method [600] further comprises determining, by the second NF, a count of existing associations, associated with the subset of attributes from the set of attributes. Also, the method [600] comprises rejecting, by the second NF, the policy control create request based on determining that the count of existing associations has reached the maximum permitted policy associations.

[0163] The method [600] terminates at step [620],

[0164] The present disclosure further discloses a non-transitory computer readable storage medium storing instructions for managing a Packet Data Unit (PDU) session establishment in a network, the instructions include executable code which, when executed by a one or more units of a system [100], causes: a first transceiver unit [102] to receive the PDU session establishment request for a User Equipment (UE); and transmit, from the first NF, to a second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE. The executable code which, when executed by the one or more units of the system [100], causes: a second processing unit [110], at the second NF, to determine, one of a presence and an absence of an existing policy session associated with the set of attributes for the UE; a second transceiver unit [108], at the second NF, to: receive, maximum permitted policy sessions and a count of established policy sessions, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy session; and the second processing unit [110], at the NF, to determine, whether the count of established policy sessions is one of below and equal to the maximum permitted policy sessions associated with the subset of attributes. The executable code which, when executed by the one or more units of the system, causes: a second processing unit [110], at the NF, to accept, the PDU session establishment request for the UE, based on the determination that the count of established policy sessions is below the maximum permitted policy sessions.

[0165] Yet another aspect of the present disclosure may relate to a non-transitory computer-readable storage medium storing instructions for managing a Packet Data Unit (PDU) session establishment in a network, the instructions comprising executable code which, when executed by one or more units of a system, causes: a first transceiver unit [102] to receive the PDU session establishment request for a User Equipment (UE); connect to a second NF to process the PDU session establishment request from the UE; and transmit, to the second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE. Further, the executable code when executed by the one or more units of the system [100], causes a second processing unit [110] to identify a first timestamp associated with the existing policy association, based on determining the presence of the existing policy association; to identify a second timestamp associated with the policy control create request; and to compare the first timestamp with the second timestamp. Also, the executable code when executed by the one or more units of the system, causes a second processing unit [110] to accept the policy control create request based on the comparison of the first timestamp with the second timestamp.

[0166] As is evident from the above, the present disclosure provides a technically advanced solution for managing a Packet Data Unit (PDU) session establishment in a network. The present disclosure provides a solution to control an increase in a number of stale sessions which in turn results in saving the signalling traffic that is sent for validation of stale sessions. Also, the present disclosure provides a solution that can optimize the resources (compute, memory and storage) used by NF by deleting or overwriting old sessions which are no longer live in network with assumption that devices in network have capabilities that are understood by service provider.

[0167] 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 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.

[0168] 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 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.

[0169] Further, in accordance with the present disclosure, it is to be acknowledged that the functionality described for the various 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 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.

Claims

WE CLAIM:

1. A method [500] for managing a Packet Data Unit (PDU) session establishment in a network, the method comprising: receiving, by a first network function (NF), a PDU session establishment request for a User Equipment (UE);

- transmitting, from the first NF, to a second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE; determining, by the second NF, one of a presence and an absence of an existing policy session associated with the set of attributes for the UE; receiving, by the second NF, a maximum permitted policy sessions and a count of established policy sessions, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy session; determining, by the second NF, whether the count of established policy control sessions is one of below and equal to the maximum permitted policy sessions associated with the subset of attributes; and accepting, by the second NF, the PDU session establishment request from the UE, based on the determination that the count of established policy sessions is below the maximum permitted policy sessions; and processing, by the first NF, one or more policy rules received from the second NF, in response to accepting the policy control create request.

2. The method [500] as claimed in claim 1, further comprising: deleting, by the second NF, the existing policy session for the UE, in an event of the presence of the existing policy session for the UE; and accepting, by the second NF, the PDU session establishment request from the UE.

3. The method [500] as claimed in claim 1, wherein the method further comprises, deleting, by the second NF, a policy session from the established policy sessions, based on the determination that the count of established policy sessions is equal to the maximum permitted policy sessions.

4. The method [500] as claimed in claim 3, wherein, the deleting the policy session from the established policy sessions, is determined based on a timestamp associated with each of the policy session from the established policy sessions.

5. The method [500] as claimed in claim 1, wherein the set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID.

6. The method [500] as claimed in claim 5, wherein the subset of attributes of the set of attributes comprises at least a SUPI, a DNN, and a network slice.

7. The method [500] as claimed in claim 1, wherein the first NF is a Session Management Function (SMF) [204] in the network.

8. The method [500] as claimed in claim 1, wherein the second NF is a Policy Control Function [216] in the network.

9. The method [500] as claimed in claim 1, further comprises:

- transmitting, by the second NF, to a third NF, a management register request for the UE comprising the subset of attributes; receiving, by the third NF, a maximum permitted binding sessions for the subset of attributes; receiving, by the third NF, a count of existing binding sessions for the subset of attributes; determining, by the third NF, whether the count of the existing binding sessions is one of below and equal to the maximum permitted binding sessions; accepting, by the third NF, the management register request from the second NF, based on the determining that the count of the existing binding sessions is below the maximum permitted binding sessions; and

- transmitting, by the third NF, an acceptance response for the management register request, to the second NF.

10. The method [500] as claimed in claim 9, wherein, based on the determination that the count of the existing binding sessions is equal to the maximum permitted binding sessions, the third NF, determines one of a rejected response and an acceptance response based on a flag in a user configurable table.

11. The method [500] as claimed in claim 10, wherein the rejected response is transmitted to the second NF, based on a true value of the flag in the user configurable table.

12. The method [500] as claimed in claim 10, wherein the acceptance response is transmitted to the second NF, based on a false value of the flag in the user configurable table.

13. The method [500] as claimed in claim 12, wherein the acceptance response comprises deleting a binding session of the existing binding sessions for the subset of attributes.

14. The method [500] as claimed in claim 13, wherein deleting the binding session from the existing binding sessions is determined based on a timestamp associated with each binding session of the existing binding sessions.

15. The method [500] as claimed in claim 9, wherein the third NF is a Binding Support Function (BSF) [208] in the network.

16. The method [500] as claimed in claim 1, further comprises:

- transmitting, by the second NF, to a fourth NF, a spending limit control session request associated with the subset of attributes; receiving, by the fourth NF, a maximum permitted spending limit control sessions for the subset of attributes; receiving, by the fourth NF, a count of existing spending limit control sessions for the subset of attributes; determining, by the fourth NF, whether the count of the existing spending limit control sessions is one of below and equal to the maximum permitted spending limit control sessions; accepting, by the fourth NF, the spending limit control session request from the second NF, based on the determining that the count of the existing spending limit control sessions is below the maximum permitted spending limit control sessions; and

- transmitting, by the fourth NF, an acceptance response for the spending limit control session request, to the second NF.

17. The method [500] as claimed in claim 16, further comprises: deleting, by the fourth NF, a spending limit control session from the existing spending limit control sessions, based on the determination that the count of the existing spending limit control sessions is equal to the maximum permitted spending limit control sessions, wherein deleting the spending limit control session from the existing spending limit control sessions is based on a timestamp associated each of the spending limit control session from the existing spending limit control sessions; accepting, by the fourth NF, the spending limit control session request, from the second NF; and

- transmitting, by the fourth NF, the acceptance response for the spending limit control session request, to the second NF.

18. The method [500] as claimed in claim 16, wherein the fourth NF is a Charging Function (CHF) [206] in the network.

19. The method [500] as claimed in claim 1, wherein the maximum permitted policy sessions, associated with the subset of attributes is received from a configurable table configured at the second NF.

20. The method [500] as claimed in claim 16, wherein the method further comprises:

- transmitting, by the first NF, to the fourth NF, a converged charging create request associated with the subset of attributes; receiving, by the fourth NF, a maximum permitted PDU sessions for the subset of attributes; receiving, by the fourth NF, a count of existing PDU sessions for the subset of attributes; determining, by the fourth NF, whether the count of the existing PDU sessions is one of below and equal to the maximum permitted PDU sessions; accepting, by the fourth NF, the converged charging create request from the first NF, based on the determining that the count of the existing PDU sessions is below the maximum permitted PDU sessions; and

- transmitting, an acceptance response for the converged charging create request, to the first NF.

21. The method [500] as claimed in claim 20, further comprising: deleting, by the fourth NF, a PDU session from the existing PDU sessions, based on the determining that the count of the existing PDU sessions is equal to the maximum permitted PDU sessions, wherein deleting of the PDU session from the existing PDU sessions is based on a timestamp associated with each of the PDU session from the existing PDU sessions; accepting, by the fourth NF, the converged charging create request, from the first NF; and

22. A system [100] for managing a Packet Data Unit (PDU) session establishment in a network, the system comprising: a first transceiver unit [102], at a first network function (NF), configured to: o receive, a PDU session establishment request for a User Equipment (UE); o transmit, from the first NF to a second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE; a second processing unit [110], at the second NF, configured to: o determine, one of a presence and an absence of an existing policy session associated with the set of attributes for the UE; a second transceiver unit [108], at the second NF, configured to: o receive, maximum permitted policy sessions and a count of established policy sessions, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy session;

- the second processing unit [110], at the second NF, further configured to: o determine, whether the count of established policy sessions is one of below and equal to the maximum permitted policy sessions associated with the subset of attributes; o accept, the PDU session establishment request for the UE, based on the determination that the count of established policy sessions is below the maximum permitted policy sessions; and a first processing unit [104], at the first NF, configured to: o process, one or more policy rules received from the second NF in response to accepting the policy control create request.

23. The system [100] as claimed in claim 22, wherein,

- the second processing unit [110], at the second NF, is further configured to:

■ delete the existing policy session for the UE, in an event of the presence of the existing policy session for the UE; and

■ accept the PDU session establishment request from the UE.

24. The system [100] as claimed in claim 22, wherein the second processing unit [110], at the second NF, is further configured to: delete, a policy session from the established policy sessions, based on the determination that the count of established policy sessions is equal to the maximum permitted policy sessions.

25. The system [100] as claimed in claim 24, wherein, the deleting the policy session from the established policy sessions, is determined based on a timestamp associated with each of the policy session from the established policy sessions.

26. The system [100] as claimed in claim 22, wherein the set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID.

27. The system [100] as claimed in claim 26, wherein the subset of attributes of the set of attributes comprises at least a SUPI, a DNN, and a network slice.

28. The system [100] as claimed in claim 22, wherein the first NF is a Session Management Function (SMF) in the network.

29. The system [100] as claimed in claim 22, wherein the second NF is a Policy Control Function in the network.

30. The system [100] as claimed in claim 22, wherein the system [100] further comprises:

- the second transceiver unit [108], at the second NF, further configured to: o transmit, to a third NF, a management register request for the UE comprising the subset of attributes; a third transceiver unit [114], at the third NF, configured to: o receive, a maximum permitted binding sessions for the subset of attributes; o receive, a count of existing binding sessions for the subset of attributes; a third processing unit [116], at the third NF, configured to: o determine, whether the count of the existing binding sessions is one of below and equal to the maximum permitted binding sessions; o accept, the management register request from the second NF, based on the determination that the count of the existing binding sessions is below the maximum permitted binding sessions; and

- the third transceiver unit [114], at the third NF, further configured to transmit, an acceptance response for the management register request, to the second NF.

31. The system [100] as claimed in claim 30, wherein, based on the determination that the count of the existing binding sessions is equal to the maximum permitted binding sessions, the third processing unit [116] at the third NF, determines one of a rejected response and an acceptance response, based on a flag value in a user configurable table.

32. The system [100] as claimed in claim 31, wherein the rejected response is transmitted by the third transceiver unit [114], to the second NF, based on a true value of the flag in the user configurable table.

33. The system [100] as claimed in claim 31, wherein, the acceptance response is transmitted by the third transceiver unit [114], to the second NF, based on a false value of the flag in the user configurable table.

34. The system [100] as claimed in claim 31, wherein the acceptance response comprises deleting, by the third processing unit [118], at the third NF, a binding session from the existing binding sessions for the subset of attributes.

35. The system [100] as claimed in claim 34, wherein the deleting of the binding session from the existing binding sessions is determined by the third processing unit [116], based on a timestamp associated with each binding session of the existing binding sessions.

36. The system [100] as claimed in claim 30, wherein the third NF is a Binding Support Function (BSF) [208] in the network.

37. The system [100] as claimed in claim 22, wherein the system [100] further comprises: the second transceiver unit [108], at the second NF, configured to: o transmit, to a fourth NF, a spending limit control session request associated with the subset of attributes; a fourth transceiver unit [120], at the fourth NF, configured to: o receive, a maximum permitted spending limit control sessions for the subset of attributes; o receive, a count of existing spending limit control sessions for the subset of attributes; a fourth processing unit [122], at the fourth NF, configured to: o determine, whether the count of the existing spending limit control sessions is one of below and equal to the maximum permitted spending limit control sessions; o accept, the spending limit control session request from the second NF, based on the determining that the count of the existing spending limit control sessions is below the maximum permitted spending limit control sessions; and the fourth transceiver unit [120], at the fourth NF, further configured to transmit, an acceptance response for the spending limit control session request, to the second NF.

38. The system [100] as claimed in claim 37, wherein the system [100] further comprises: the fourth processing unit [122], at the fourth NF, is further configured to: o delete, a spending limit control session from the existing spending limit control sessions, based on the determination that the count of the existing spending limit control sessions is equal to the maximum permitted spending limit control sessions, wherein the deleting of the spending limit control session from the existing spending limit control sessions is based on a timestamp associated with each of the spending limit control session from the existing spending limit control sessions; o accept, the spending limit control request, from the second NF; and the fourth transceiver unit [120], at the fourth NF, further configured to: o transmit, the acceptance response for the spending limit control session request, to the second NF.

39. The system [100] as claimed in claim 37, wherein the fourth NF is a Charging Function (CHF) in the network.

40. The system [100] as claimed in claim 22, wherein the maximum permitted policy control sessions, associated with the subset of attributes are received from a configurable table configured at the second NF.

41. The system [100] as claimed in claim 37, wherein the system further comprises: the first transceiver unit [102], at the first NF, further configured to: o transmit, to the fourth NF, a converged charging create request associated with the subset of attributes; the fourth transceiver unit [120], at the fourth NF, further configured to: o receive, a maximum permitted PDU sessions for the subset of attributes; o receive, a count of existing PDU sessions for the subset of attributes; the fourth processing unit [122], at the fourth NF, further configured to: o determine, whether the count of the existing PDU sessions is one of below and equal to the maximum permitted PDU sessions; o accept, the converged charging create request from the first NF, based on the determination that the count of the existing PDU sessions is below the maximum permitted PDU sessions; and the fourth transceiver unit [120], at the fourth NF, further configured to transmit an acceptance response for the converged charging create request, to the first NF.

42. The system [100] as claimed in claim 41, wherein, the system further comprises: the fourth processing unit [122], at the fourth NF, further configured to: delete, a PDU session from the existing PDU sessions, based on the determination that the count of the existing PDU sessions is equal to the maximum permitted PDU sessions, wherein deleting the PDU session from the existing PDU sessions, is based on a timestamp associated with each of the PDU session from the existing PDU sessions. accept, the charging service request, from the first NF; and the fourth transceiver unit [120], at the fourth NF, further configured to:

- transmit, an acceptance response for the converged charging create request, to the first NF.

43. A method [600] for managing a Packet Data Unit (PDU) session establishment in a network, the method comprising: receiving, by a first network function (NF), a PDU session establishment request for a User Equipment (UE); connecting, by the first NF, to a second NF to process the PDU session establishment request for the UE;

- transmitting, by the first NF, to the second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE; determining, by the second NF, one of a presence and an absence of an existing policy association, associated with the set of attributes for the UE; identifying, by the second NF, a first timestamp associated with the existing policy association, based on determining the presence of the existing policy association; identifying, by the second NF, a second timestamp associated with the policy control create request; comparing, by the second NF, the first timestamp and the second timestamp; accepting, by the second NF, the policy control create request based on the comparing; and processing, by the first NF, one or more policy rules received from the second NF, in response to accepting the policy control create request.

44. The method [600] as claimed in claim 43, wherein, the comparing by the second NF, the first timestamp and the second timestamp comprises: determining, if the second timestamp is greater than the first timestamp.

45. The method [600] as claimed in claim 44, wherein accepting the policy control create request is based on determining that the second timestamp is greater than the first timestamp.

46. The method [600] as claimed in claim 43, wherein, accepting by the second NF, the policy control create request, comprises: deleting, the existing policy association.

47. The method [600] as claimed in claim 43, wherein the set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID.

48. The method [600] as claimed in claim 47, further comprises: receiving, by the second NF, a maximum permitted policy associations, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy association; determining, by the second NF, a count of existing policy associations, associated with the subset of attributes from the set of attributes; and rej ecting, by the second NF, the policy control create request based on determining that the count of existing policy associations has reached the maximum permitted policy associations.

49. The method [600] as claimed in claim 48, wherein the subset of attributes comprises at least a SUPI, a DNN, and a network slice.

50. A system [100] for managing a Packet Data Unit (PDU) session establishment in a network, the system comprising: a first transceiver unit [102], at a first network function (NF), configured to: o receive a PDU session establishment request for a User Equipment (UE); o connect to a second NF to process the PDU session establishment request from the UE; o transmit, to the second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE; a second processing unit [110], at the second NF, configured to: o determine one of a presence and an absence of an existing policy association associated with the set of attributes for the UE; o identify a first timestamp associated with the existing policy association, based on determination of the presence of the existing policy association; o identify a second timestamp associated with the policy control create request; and o compare the first timestamp with the second timestamp. o accept the policy control create request based on the comparison of the first timestamp with the second timestamp; and a first processing unit [104], at the first NF, configured to: o process, one or more policy rules received from the second NF, in response to accepting the policy control create request.

51. The system [100] as claimed in claim 50, wherein the second processing unit [110], at the second NF, upon the comparison of the first timestamp with the second timestamp, is further configured to determine if the second timestamp is greater than the first timestamp.

52. The system [100] as claimed in claim 51, wherein the second processing unit [110] at the second NF, is configured to accept the policy control request based on determining that the second timestamp is greater than the first timestamp.

53. The system [100] as claimed in claim 50, wherein the second processing unit [110] at the second NF, is further configured to delete the existing policy association.

54. The system [100] as claimed in claim 50, wherein the set of attributes comprises a Subscription Permanent Identifier (SUPI), a Data Network Name (DNN), a network slice, and a PDU Session ID.

55. The system [100] as claimed in claim 54, wherein the system further comprises a second transceiver unit [108] at the second NF, configured to: receive, a maximum permitted policy associations, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy association; determine a count of existing policy associations, associated with the subset of attributes from the set of attributes; and reject the policy control create request based on determining that the count of existing policy associations has reached the maximum permitted policy associations.

56. The system [100] as claimed in claim 55, wherein the subset of attributes comprises at least the SUPI, DNN, and the network slice.

57. A non-transitory computer-readable storage medium storing instructions for managing a Packet Data Unit (PDU) session establishment in a network, the instructions comprising executable code which, when executed by one or more units of a system, causes: a first transceiver unit [102], at a first network function (NF) to: o receive, a PDU session establishment request for a User Equipment (UE); o transmit, from the first NF, to a second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE; a second processing unit [110], at the second NF, to: o determine, one of a presence and an absence of an existing policy session associated with the set of attributes for the UE; a second transceiver unit [108], at the second NF, to: o receive, maximum permitted policy sessions and a count of established policy sessions, associated with a subset of attributes from the set of attributes, in an event of the absence of the existing policy session; the second processing unit [110], at the second NF, to: o determine, whether the count of established policy sessions is one of below and equal to the maximum permitted policy sessions associated with the subset of attributes; and o accept, the PDU session establishment request for the UE, based on the determination that the count of established policy sessions is below the maximum permitted policy sessions; and a first processing unit [104], at the first NF, configured to: o process, one or more policy rules received from the second NF in response to accepting the policy control create request.

58. A non-transitory computer-readable storage medium storing instructions for managing a Packet Data Unit (PDU) session establishment in a network, the instructions comprising executable code which, when executed by one or more units of a system, causes: a first transceiver unit [102] at a first NF, to: o receive a PDU session establishment request for a User Equipment (UE); o connect to a second NF to process the PDU session establishment request from the UE; o transmit, to the second NF, a policy control create request comprising a set of attributes associated with the PDU session establishment request for the UE; a second processing unit [110] at the second NF, to: o determine one of a presence and an absence of an existing policy association associated with the set of attributes for the UE; o identify a first timestamp associated with the existing policy association, based on determining the presence of the existing policy association; o identify a second timestamp associated with the policy control create request; and o compare the first timestamp with the second timestamp. o accept the policy control create request based on the comparison of the first timestamp with the second timestamp; and a first processing unit [104] at the first NF, to: o process one or more policy rules received from the second NF in response to accepting the policy control create request.