Method and system for effective service fulfillment in communication networks

Abstract

As attached

Description

Technical Field

[001] This disclosure relates generally to network services, and more particularly to methodand system for effective service fulfilment in a communication network.Background

[002] Network slicing refers to a process of creating network slices by partitioning of anetwork into several virtual networks as per need of end users, wherein each such virtual network isconfigured and optimized for particular application(s) / service(s). Moreover, network slicing may beemployed to efficiently cater to different kinds of services with varying performance requirements.In a network employing network slicing, service fulfillment may have following challenges includinginsufficient availability of resources or network slice instances that leads to service refusal,insufficient availability of suitable types of resources or network slices that may lead to servicerefusal, and static or inappropriate allocation of resources and / or network slices leading to serviceSLA non-compliance and / or inappropriate fulfillment.

[003] In order to provide effective service fulfillment, it becomes essential for a serviceprovider to take into account incoming service requests and perform demand-based network slicingand dynamic allocation of resources, taking into consideration present and future needs, based onpattern and nature of service requests over a period of time. Currently, existing mechanisms focus onappropriate resource allocation taking into consideration service performance requirements (SLAs)and service characteristics, determining of service profile and slice profiles based on user entitlementand service class in addition to performance requirements (SLAs) and service characteristics, networkslice instance resource allocation optimization, and optimal resource allocation.

[004] However, none of the existing mechanisms provide effective service fulfillment as theexisting mechanisms only keeps track of resource usage per slice and per service which may lead toservice denial under conditions of insufficient resources of appropriate type relevant for the serviceclass and user category. Further, the existing mechanisms do not efficiently cater to new servicerequests, as under conditions of insufficient resources of the appropriate type, service denial orinappropriate resource allocation may happen for new service requests. Moreover, existingmechanisms provides optimization of resources for each active slice instance, this may result inlimited optimization only (due to local optimization at each slice instance level) without consideringthe services running on different slices, service classes of the active services, and the type of resourcesallocated to those services. This limitation could result in service denial or service fulfillment issuesdue to insufficient resources of the appropriate type.

[005] Therefore, there is a need of a mechanism for proving efficient and effective servicefulfillment in a communication network.SUMMARY

[006] In an embodiment, a method for effective service fulfilment in a communicationnetwork is disclosed. In one embodiment, the method may include determining utilization of each ofa plurality of resources for each of a plurality of network slice instances. It should be noted that, eachof the plurality of network slice instances includes a set of network slice subnet instances. The methodmay further include determining a service allocation schedule and a service resource utilization acrossone or more service classes and one or more resource classes for each of the plurality of resources.The method may further include determining at least one of a set of possible actions required to beperformed in at least one of the plurality of resources, a plurality of services, and the plurality ofnetwork slice instances based on a consolidation plan. It should be noted that, the consolidation planis created based on the service allocation schedule and the service resource utilization. The methodmay further include assessing an impact of each of the set of possible actions based on a plurality offactors. It should be noted that, the plurality of factors comprises at least one of dynamic networkconditions, active network slice instances, and service instances. The method may further includetriggering a relevant network function(s) to perform at least one of the set of determined possibleactions based on the assessed impact.

[007] In another embodiment, a system effective service fulfilment in a communicationnetwork is disclosed. The system includes a processor and a memory communicatively coupled to theprocessor, wherein the memory stores processor executable instructions, which, on execution, causesthe processor to determine utilization of each of a plurality of resources for each of a plurality ofnetwork slice instances. It should be noted that, each of the plurality of network slice instancesincludes a set of network slice subnet instances. The processor executable instructions further causethe processor to determine a service allocation schedule and a service resource utilization across oneor more service classes and one or more resource classes for each of the plurality of resources. Theprocessor executable instructions further cause the processor to determine at least one of a set ofpossible actions required to be performed in at least one of the plurality of resources, a plurality ofservices, and the plurality of network slice instances based on a consolidation plan. It should be notedthat, the consolidation plan is created based on the service allocation schedule and the service resourceutilization. The processor executable instructions further cause the processor to assess an impact ofeach of the set of possible actions based on a plurality of factors, wherein the plurality of factorscomprises at least one of dynamic network conditions, active network slice instances, and serviceinstances. The processor executable instructions further cause the processor to trigger a relevantnetwork function(s) to perform at least one of the set of determined possible actions based on theassessed impact.

[008] It is to be understood that both the foregoing general description and the followingdetailed description are exemplary and explanatory only and are not restrictive of the invention, asclaimed.BRIEF DESCRIPTION OF THE DRAWINGS

[009] The accompanying drawings, which are incorporated in and constitute a part of thisdisclosure, illustrate exemplary embodiments and, together with the description, serve to explain thedisclosed principles.

[010] FIG. 1 represents a block diagram of a system for effective service fulfilment in acommunication network, in accordance with some embodiment.

[011] FIG. 2 illustrates a functional block diagram of various modules within an end- to-endorchestrator for effective service fulfilment in a communication network, in accordance with someembodiment.

[012] FIG. 3 illustrates a flowchart of a method for effective service fulfilment in acommunication network, in accordance with some embodiment.

[013] FIG. 4 illustrates a detailed flowchart of a method for effective service fulfilment in acommunication network, in accordance with some embodiment.

[014] FIG. 5A - 5B is a table depicting resource utilization across different geographicalarea by a plurality of network slice instance and a plurality of slice subnet instance, in accordancewith some exemplary embodiment.

[015] FIG. 6 is a table depicting level of occupancy of each of a plurality of resources acrossone or more services and service classes for different geographical areas, in accordance with someexemplary embodiment.DETAILED DESCRIPTION

[016] Exemplary embodiments are described with reference to the accompanying drawings.Wherever convenient, the same reference numbers are used throughout the drawings to refer to thesame or like parts. While examples and features of disclosed principles are described herein,modifications, adaptations, and other implementations are possible without departing from the spiritand scope of the disclosed embodiments. It is intended that the following detailed description beconsidered as exemplary only, with the true scope and spirit being indicated by the following claims.Additional illustrative embodiments are listed below.

[017] Referring now to FIG. 1, a block diagram of a system 100 for effective servicefulfilment in a communication network is illustrated, in accordance with an embodiment. The system100 displays an end-to-end network view of various components in a network that is configured forservice fulfillment. The system 100 may include an Operations Support System and Business SupportSystem (OSS / BSS) 102. The OSS / BSS 102 may be connected to a template controller 104, and anend-to-end orchestrator 106 via an interface 'I1a' and 'I1b' respectively. In an embodiment, thetemplate controller 104 may interact and exchange information with the end-to-end orchestrator 106via an interface 'I-int'. Further, the end-to-end orchestrator 106 of the system 100 may interact witheach of a Radio Access Network (RAN) manager (also referred as RAN orchestrator) 108, a SoftwareDefined Network Orchestrator (SDN-O) 110, and a Network Functions Virtualization Orchestrator(NFV-O) 112, via an interface 'I2'.

[018] Further, the RAN manager 108 may interact with a plurality RAN network slices 114via an interface 'I3'. In an embodiment, each of the plurality of RAN network slices 114 may includea plurality of slice subnet instances (also referred as slice subnets). By way of an example, each ofthe plurality of RAN network slices 114 may include slice subnets '1a' to 'na'. Moreover, each of theplurality of slice subnets, i.e., '1a' to 'na' may include a plurality of Virtual Network Functions(VNFs) and a plurality of Physical Network Functions (PNFs).

[019] Further, the SDN-O 110 may interact with a plurality transport network slices 116 viaan interface 'I3'. In an embodiment, each of the plurality of transport network slices 116 may includea plurality of slice subnet instances (also referred as slice subnets). By way of an example, the pluralityof transport network slices 116 may include slice subnets '1b' to 'mb'. Moreover, each of the pluralityof slice subnets, i.e., '1b' to 'mb' may include Internet Protocol Data Plane (IP DP) and Optical DP.Further, the NFV-O 112 may interact with a plurality of core network slices 118 via an interface 'I3'.In an embodiment, each of the plurality of core network slices 118 may include a plurality of slicesubnet instances (also referred as slice subnets). By way of an example, each of the plurality of corenetwork slices 118 may include slice subnets '1c' to 'kc'. Moreover, each of the plurality of slicesubnets, i.e., '1c' to 'kc' may include, VNFs, for example, VNF1 and VNFr. Further, the end-to-endorchestrator 106 and the NFV-O 112 may interact with common functions 120 via an interface 'I5'and the interface 'I3' respectively. The common functions 120 may include charging, measurement,policy, subscriber data (and its management), and an analytics module (also referred as cognitivemodule).

[020] Referring now to FIG. 2, a block diagram of various modules within the end-to-endorchestrator 106 configured for effective service fulfilment in a communication network is illustrated,in accordance with an embodiment. The end-to-end orchestrator 106 includes a policy andprovisioning sub-system (POL-PROV-SS) 202, a network service lifecycle orchestration sub-system(NTW-SERV-ORCH-SS) 204, a resource budget determination sub-system (RES-BUD-SS) 206, ananalytics and cognitive functions sub-system (AN-COF-SS) 208, a network slice lifecycleorchestration sub-system (NTW-SL-ORCH-SS) 210, a slice and service monitoring sub-system (SLSRV-MON-SS) 212, a network slice template configuration sub-system (NTW-ST-CONF-SS) 214,a resource orchestration sub-system (RES-ORCH-SS) 216, and slice, service, and network resource inventory (SL-SRV-RES-INV) 218.

[021] The POL-PROV-SS 202 may be configured to receive information including all policyand provisioned inputs. The POL-PROV-SS 202 may then send relevant aspects of the receivedinformation to relevant sub-systems in the end-to-end orchestrator 106. The POL-PROV-SS 202 mayalso receive request for service creation, modification, deletion, activation, and deactivation from theOSS 102. In addition to existing functionalities, the POL-PROV-SS 202 may obtain inputs abouts allthe policies and rules associated with service classes and resource classes, allocation of a plurality ofnetwork slices to specific service classes, etc. In an embodiment, these inputs may be captured throughregulatory or network policy provisioning, or it may be queried by the POL-PROV-SS 202 to theOSS 102.

[022] The NTW-SERV-ORCH-SS 204 may be responsible for orchestration of a networkservice including service instantiation (on the network slice provided by the NTW-SL-ORCH-SS 210in the presence of network slicing). Further, the NTW-SERV-ORCH-SS 204 may be responsible forscaling up / down resources and limits for access, healing, modification, and termination of the service.In addition to its existing functions, the NTW-SERV-ORCH-SS 204 may provide updates to theNTW-SL-ORCH-SS 210 on service class and priority treatment, upgrade of priority or service class,etc. Moreover, the NTW-SERV-ORCH-SS 204 may re-instantiate the service on a new network slicedue to consolidation or other changes triggered by the NTW-SL-ORCH-SS 210, based on the inputscaptured by NTW-SERV-ORCH-SS 204. In addition, the NTW-SERV-ORCH-SS 204 maydetermine requirement for change in resource category allocated to the service. In reference to FIG.1, based on the determined requirement, the NTW-SERV-ORCH-SS 204 may update the OSS 102accordingly (e.g., for appropriate charging for the service).

[023] The RES-BUD-SS 206 may be configured to determine appropriate resource budgetsfor every network segment / sub-net in the network slice based on a Software RequirementSpecification (SRS) and dynamic network conditions. Examples of the resource budgets may include,but is not limited to, a latency and a throughput budget for each network segment / sub-net, accesstype, etc. The RES-BUD-SS 206 may adapt the resource budgets based on trigger received from theNTW-ST-CONF-SS 214. The trigger received from the NTW-ST-CONF-SS 214 may include anadapted SRS. Moreover, the RES-BUD-SS 206 may adapt thresholds and parameter weights, etc.used in determination of the resource budgets with relevant inputs from the SL-SRV-MON-SS 212and the AN-COF-SS 208. In addition to its existing functionalities, the RED-BUD-SS 206 may adaptrankings of solutions to be aligned with the service class to which the service request belongs.

[024] The AN-COF-SS 208 may be responsible for performing all analytics and cognitivefunctions related to service and slice orchestration. Moreover, the AN-COF-SS 208 may be invokedby the relevant sub-system for performing necessary prediction / detection. In an embodiment, the ANCOF-SS 208 may be invoked by the NTW-SL-ORCH-SS 210, the NTW-ST-CONF-SS 214, the SLSRV-MON-SS 212, or the NTW-SERV-ORCH-SS 204. Examples of prediction / detection performedby the AN-COF-SS 208 may include, but is not limited to, resource occupancy trend in a networkslice, and a root cause analysis for a network segment failure. Further, the AN-COF-SS 208 mayprovide relevant inputs on capability of each of the plurality of network segments to the RES-BUDSS 206 during determination of resource budgets for the each of the plurality of network segments.Moreover, the AN-COF-SS 208 may also provide relevant inputs for adjustments to the rules andthresholds for determining updates to the SRS based on USER-ENTLMENT. In addition to itsexisting functions, the AN-COF-SS 208 may provide traffic patterns per service, per service class,per geographic area, per network slice instance, per network slice sub-net instance, per time interval,etc. that are predicted at a granular as well as aggregated level. The AN-COF-SS 208 may also provideresource occupancy levels per service, per service class, per slice instance, per resource category, pergeographic area, per time interval, etc. that are predicted at a granular as well as aggregated level.Additionally, the AN-COF-SS 208 may predict fault / performance issues per resource type andcategory, per service class, per slice instance, etc. Further, the AN-COF-SS 208 may provide thepredicted traffic patterns, the predicted resource occupancy levels, and the predictedfault / performance issue to the relevant sub-systems, such as, the NTW-SERV-ORCH-SS 204, theNTW-SL-ORCH-SS 210, etc.

[025] The NTW-SL-ORCH-SS 210 may be responsible for all orchestration functionsassociated with each of the plurality of network slices. The orchestration functions may include, butis not limited to, instantiation of a new network slice, scaling up / down, healing and makingmodifications, and terminating / decommissioning the network slice. As will be appreciated, the NTW-SL-ORCH-SS 210 may work close with the NEW-ST-CONF-SS 214 in order to instantiate or reusean appropriate network slice instance. In addition to its existing functions, the NTW-SL-ORCH-SS210 may determine need for reallocation of resources to existing network slices and services in orderto enable service fulfillment under resource-constrained situations. Moreover, the NTW-SL-ORCHSS 210 may determine need for consolidation of services and network slices, and the resourcesallocated to the network slices. The NTW-SL-ORCH-SS 210 may also determine consolidation to bedone to the network slices. The NTW-SL-ORCH-SS 210 may determine need for re-mapping one ormore services to different network slices. Additionally, the NTW-SL-ORCH-SS 210 may determineways to fulfill the service request under resource-constrained conditions based on policy, dynamicnetwork conditions, other services and slices that are active, etc. and triggers the NTW-ST-CONFSS 214 accordingly for providing a suitable network slice instance. The NTW-SL-ORCH-SS 210may trigger the RES-ORCH-SS 216 for appropriate allocation / reallocation / optimization of resourceswhen the service request is received, and appropriate reallocation / optimization of resources based onanalysis of Fault Management (FM) and Performance Management (PM) data. Examples of FM datainclude, but is not limited to, alarms and threshold crossing alerts. Examples of PM data include, butis not limited to, traffic counters, resource occupancy trends, and Key Performance Indicator values.

[026] The SL-SRV-MON-SS 212 may be responsible for monitoring adherence levels of thenetwork slice (end-to-end as well as network segment / sub-net level), service target KPIs, andrequirements. The SL-SRV-MON-SS 212 may report any fault / performance issues in the networkslice or the services to the NTW-SL-ORCH-SS 210 or the NTW-SERV-ORCH-SS 204 respectively.The SL-SRV-MON-SS 212 may monitor adherence levels of the resource budgets allocated to variousnetwork subnets. In addition to its existing functions, the SL-SRV-MON-SS 212 may also provide agranular as well as aggregated view of various fault and performance events in the network slices andservices, including service-class level resource occupancy, service-level resource occupancy in ashared network slice instance or a slice sub-net instance, occupancy levels of each resource categoryper geographic area, and resource occupancy levels per geographical area (could be region, cell-level,tracking area level, registration area level, data-center level, etc.), etc.

[027] The NTW-ST-CONF-SS 214 may be responsible for determining a suitable networkslice instance for fulfilling the service request upon receiving a trigger from the NTW-SL-ORCH-SS210. The determination of the suitable network slice instance by the NTW-ST-CONF-SS 214 mayinclude providing details of an existing network slice instance that may be reused, and / or creation ofa new network slice instance that includes details of the existing network slice subnet instances thatcan be reused (as-is or with minor modifications), and / or details of new network slice subnetinstance(s) that needs to be created. In addition, the NTW-ST-CONF-SS 214 may trigger the RESBUD-SS 206 for determining resource budgets for various network segments / sub-nets when the newnetwork slice instance needs to be created. Further, the NTW-ST-CONF-SS 214 may provide updatednetwork slice instance allocation information when triggered by the NTW-SL-ORCH-SS 210 with anadapted SRS (i.e., the updated SRS). In addition to its existing functions, the NTW-ST-CONF-SS214 may consider additional inputs received from the NTW-SL-ORCH-SS 210 when determining aN-S shell hierarchy (for e.g., consider resources of higher category that may be normally allocatedfor a specific type of network slice instance or service).

[028] The RES-ORCH-SS 216 may be responsible for performing resource orchestration forthe service or the network slice. In addition to its existing functions, the RES-ORCH-SS 216, underdirection of the NTW-SL-ORCH-SS 210, may determine appropriate resources to be allocated for thereceived slice request during scarcity / unavailability of resources of the required resource category.Further, the RES-ORCH-SS 216 may determine resources to be reallocated to the existing networkslices and services running on those network slices. In addition, the RES-ORCH-SS 216 maydetermine resources to be optimized in the existing network slices and services running on thosenetwork slices.

[029] The SL-SRV-RES-INV 218 may correspond to a component that contains details ofnetwork slice templates and active network slice instances, slice subnet templates and active networkslice sub-net instances, the SRS, resources allocated to each slice and slice subnet, active services,and details of network slice to which those services are mapped to. In addition to existing information,the SL-SRV-RES-INV 218 component may store information about resource allocation per resourcetype and category (including historical details of allocation / reallocation), network slice to servicemapping (current as well as historical), network slice subnet to network slice mapping (current aswell as historical), history of scaling, etc.

[030] Referring now to FIG.3, a flowchart of a method 300 for effective service fulfilmentin a communication network is illustrated, in accordance with some embodiment. At step 302,utilization of each of a plurality of resources may be determined for each of a plurality of networkslice instances. In an embodiment, each of the plurality of network slice instances may include a setof network slice subnet instances. In order to determine utilization of each of the plurality of resources,initially, in one embodiment, an availability of an appropriate resource from the plurality of resourcesmay be determined upon receiving a new service request. The new service request may includeperformance requirements, a priority, a class associated with users, a geographical area of a service,a service class, and a duration of the service. In order to determine availability, a requirement of theappropriate resource(s) may be determined for the new service request. The requirement of theappropriate resource may be determined based on a set of service factors. The set of service factorsmay include service characteristics, service performance requirements, and service dimensions.

[031] Moreover, in order to determine availability, initially, a first set of resource budgetsand service performance requirements may be determined for each of the set of network slice subnetinstances that shall form part of the network slice instance on which the new service shall run. Inaddition, a network shell hierarchy may be determined using a template hierarchy. The network shellhierarchy may include a slice subnet hierarchy. Further, based on the determined availability, arequirement for a change in one or more of the plurality of network slice instances may be identifiedin order to fulfil the new service request. In the present embodiment, the determination of the networkshell hierarchy may correspond to identification of one of a reuse of an existing network slice instanceor creation of a new network slice instance. Moreover, in order to create the new network sliceinstance, one of a reuse of an existing network slice subnet instance or creation of a new network slicesubnet instance may be determined based on the slice subnet hierarchy.

[032] In another embodiment, initially, at least one of a fault management data or aperformance management data may be received from the communication network. Further, the atleast one of the fault management data or the performance management data may be analyzed toidentify one or more faults or one or more performance issues in the communication network. Inpresent embodiment, the plurality of faults or the plurality of performance issues may be identifiedbased on a pre-defined threshold, a pre-defined performance criteria, or a service level criteria. Oncethe plurality of faults or the plurality of performance issues are identified, then an impact of theplurality of faults or the plurality of performance issues on at least one of the plurality of networkslice instances, the set of network slice subnet instances, services and service classes, and impactedgeographical areas may be analyzed. Upon determining the impact, a requirement for a change in oneor more of the plurality of network slice instances and / or one or more services may be identified. Therequirement for the change may be identified based on an analysis of at least one of the faultmanagement data or the performance management data.

[033] Further, at step 304, a service allocation schedule and a service resource utilizationmay be determined across one or more service classes and one or more resource classes for each ofthe plurality of resources. In an embodiment, determination of the service allocation schedule and theservice resource utilization includes determination of service level resource utilization and serviceclass level resource utilization. The service level resource utilization and the service class levelresource utilization may be determined based on the plurality of resources allocated to one or moreservices belonging to one or more service classes in various geographical areas associated with theservice.

[034] Upon determining the service allocation schedule and the service resource utilization,at step 306, at least one of a set of possible actions required to be performed in at least one of theplurality of resources, a plurality of services, and the plurality of network slice instances may bedetermined based on a consolidation plan. In an embodiment, the consolidation plan may be createdbased on the service allocation schedule and the service resource utilization. Moreover, the set ofpossible actions may include, but is not limited to, modification of resource allocation, merging ofnetwork slices, splitting of network slices, modification of network slices, and re-mapping one ormore services to at least one of the network slice instances.

[035] Further, at step 308, an impact of each of the set of possible actions may be assessedbased on a plurality of factors. The plurality of factors may include at least one of dynamic networkconditions, active network slice instances, and service instances. Moreover, the impact assessment ofeach of the set of possible actions may include at least one of an impact on service level criteria orkey performance indicators of currently active services, an impact on service continuity of currentlyactive services, an impact on performance of a network slice instance(s) or a network slice subnetinstance upon mapping the new service or during at least one of the set of possible actions, an impactof minimum resource availability, and an impact on billing.

[036] Based on the assessed impact, at step 310, relevant network function(s) may betriggered to perform at least one of the set of determined possible actions. Once the at least one of theset of determined possible action is performed, then, an effectiveness of performing the at least oneof the set of modifications may be verified based on a new network slice shell hierarchy provided forthe new service request. Further, a corrective action may be performed based on the effectiveness ofthe at least one of the set of possible actions.

[037] Referring now to FIG. 4, a detailed flowchart of a method 400 for effective servicefulfilment in a communication network is illustrated, in accordance with some embodiments. As willbe appreciated, the detailed flowchart described in present FIG. 4 has been explained in reference tothe FIG. 2. In one embodiment, in order to perform effective service fulfillment, initially, at step 402,the POL-PROV-SS 202 in an end-to end orchestrator may receive a new service request (also referredas a service creation request) from an OSS / BSS over an interface 'I1b'. In refence to FIG. 1, the endt-end orchestrator may correspond to the end-to-end orchestrator 106. In addition, the OSS / BSS maycorrespond to the OSS / BSS 102. In an embodiment, the new service request may includeperformance requirements, a priority, a class associated with users, a geographical area of the service(i.e., coverage area of the service), a service class associated with the service, and a duration of theservice. The POL-PROV-SS 202 may then pass the new service request to the NTW-SERV-ORCHSS 204.

[038] Upon receiving the new service request, at step 404, resource requirements for the newservice request may be determined to fulfil the new service request. Moreover, the requirement of theappropriate resources may be determined based on the set of service factors. The set of service factorsmay include service characteristics, service performance requirement, and service dimensions. In anembodiment, the NTW-SL-ORCH-SS 210 may determine service characteristics (SRV-CHAR),service performance requirements (SRV-PERF-REQ), and service dimensions (SRV-DIM). Once theset of service factors are determined, then the NTW-SL-ORCH-SS 210 may form the SRS asdescribed in prior art (dynamic slicing).

[039] The NTW-SL-ORCH-SS 210 may then determine enhancements and adjustments tobe done to the requirements of the new service request in the SRS based on user entitlement asdescribed in prior art (resource budget). Further, the NTW-SL-ORCH-SS 210 may then form anupdated SRS. The updated SRS may include updated service characteristics (UPD-SRV-CHAR),updated service performance requirements (UPD-SRV-PERF-REQ), and updated service dimensions(UPD-SRV-DIM). The NTW-SL-ORCH-SS 210 may then trigger the NTW-ST-CONF-SS 214 withthe updated SRS for allocation of a suitable network slice instance on which the new service can beinstantiated.

[040] The NTW-ST-CONF-SS 214 may then request for a suitable template hierarchy to atemplate controller using relevant information present in the UPD-SRS (e.g., the UPD-PERF-REQ,and the UPD-SRV-CHAR). In reference to FIG. 1, the template controller may correspond to thetemplate controller 104. Further, the template controller may provide the requested suitable templatehierarchy using an existing mechanism. Upon reception of the suitable template hierarchy from thetemplate controller, the NTW-ST-CONF-SS 214 may determine whether any existing network sliceinstance can be reused. After determining reuse of the existing network slice instance, the NTW-STCONF-SS 214 may trigger the RES-BUD-SS 206 to determine resource budgets for each of theplurality of network subnets instance present in the template hierarchy as provided by the templatecontroller. In an embodiment, the RES-BUD-SS 206 may give a higher rank to a solution that issupporting same class of the new service request.

[041] Further, at step 406, an availability of appropriate resources may be determined. In anembodiment, the NTW-ST-CONF-SS 214 may fetch the first set of resource budgets and serviceperformance requirements (also referred as resource budget performance requirement, i.e., RESBUD-PERF-RQMTS) provided by the RES-BUD-SS 206 for each of the plurality of subnets. Further,the NTW-ST-CONF-SS 214 may determine an appropriate network slice shell hierarchy, slice subnet characteristics determined earlier, and RES-BUD-PERF-RQMTS as described in prior art. In anembodiment, the network slice hierarchy may include the slice subnet hierarchy and is determinedusing the template hierarchy determined by the template controller. This determination of theappropriate network slice shell hierarchy may also include determination of whether an existingnetwork slice subnet instance can be reused, or a new network slice subnet instance needs to be createdfor each of the plurality of subnets. A process of determination of the appropriate network slice shellhierarchy may be repeated until a suitable network slice shell hierarchy is determined with feasibilityto cater to the new service request (i.e., fulfill both performance requirements and resourcerequirements), or when all options are exhausted.

[042] During determination of the appropriate network slice shell hierarchy three scenariosmay be possible. By way of an example, in the first scenario, suppose sufficient resources may beavailable when deciding to reuse an existing slice instance or an existing slice subnet instance, evenafter catering to the new service request. In other words, the first scenario may include both situations,i.e., decision of reuse of the existing network slice instance or creation of the new network sliceinstance using the existing network slice subnet instances or new network slice subnet instances. Inthis scenario, sufficiency of requirements may be checked by the NTW-ST-CONF-SS 214 against apre-defined threshold (also referred as resource availability thresholds, i.e., RES-AVAILTHRESHOLD) for particular resource type and resource category, and for various service classes thatare currently served by the communication network.

[043] The check for the sufficiency of requirements may be done by the NTW-ST-CONFSS 214 after determining need for scaling resources of the particular network slice instance or thenetwork slice subnet instance when deciding to reuse an existing network slice instance or whencreating a new network slice instance by reusing the existing network slice subnet instance(s)respectively. Moreover, in this scenario, remaining steps, i.e., step 414 to step 422 may be skipped,unless number of network slice instances or network slice subnet instances of the particular networkslice instance exceed a pre-defined threshold, i.e., a network slice neighboring threshold (N-S-NBRTHRES).

[044] By way of another example, consider a second scenario, where sufficient resourcesmay be available for the new service request, however, remaining resource levels fall below theresource availability thresholds. In this scenario, the NTW-ST-CONF-SS 214 may provide relevantinputs to the NTW-SL-ORCH-SS 210 for determining the next step to be executed. Step 414 is thencarried out next. By way of yet another example, consider a third scenario, where sufficient resourcesmay not be available to fulfill the new service request. In this scenario, the NTW-ST-CONF-SS 214may provide relevant inputs to the NTW-SL-ORCH-SS 210 for determining the next step forexecution. Step 414 is then carried out next.

[045] In another embodiment, in order to perform effective service fulfillment, initially atstep 408, an intimation about one of a fault event or performance event may be received. Further,upon receiving the intimation, at least one of the fault management data or the performancemanagement data may be fetched from the communication network. Upon reception of the at leastone of fault management data or the performance management data from the communication network,the SL-SRV-MON-SS 212 stores may store the at least one of fault management data or theperformance management data in a database (also referred as data lake). The SL-SRV-MON-SS 212may then trigger the AN-COF-SS 208 to analyse the fault management data, or the performancemanagement data reported from the communication network.

[046] Once the at least one of the fault management data or the performance managementdata are fetched, at step 410, service level agreement (SLA) and resource utilization level may bedetermined. In order to determine the SLA and the resource utilization level, the AN-COF-SS 208may perform the analysis as instructed by the SL-SRV-MON-SS 212. Based on the analysis of thefault management data, upon identifying one or more faults, the AN-COF-SS 208 may analyze animpact of the one or more faults on the plurality of network slice instances, the plurality of networkslice subnet instances, services and service classes, geographical areas impacted, etc. Further, basedon the analysis of the performance data, the AN-COF-SS 208 may predict traffic patterns and resourceoccupancy levels. In addition to the traffic patterns and the resource occupancy levels, the AN-COFSS 208 may predict potential faults or SLA / KPI adherence issues associated with one or more of theplurality of network slice instances and / or service instances.

[047] Based on the prediction, when any reporting condition is fulfilled (e.g., occurrence ofa fault in a service) or any of the pre-defined thresholds are crossed (e.g., resource occupancy levelthreshold, SLA / KPI adherence level threshold, SLA / KPI violation probability threshold, etc.), theAN-COF-SS 208 may intimate the NTW-SL-ORCH-SS 210 and the NTW-SERV-ORCH-SS 204 forissues in one or more of the plurality of network slice instances, the plurality of network slice subnetinstances, and services respectively. In an embodiment, the analysis and the prediction may be doneby the AN-COF-SS 208 using well-known techniques such as linear regression, supervised learning,other machine learning or analytics techniques, or using proprietary mechanisms.

[048] Further, at step 412, a requirement for a change in one or more of the plurality ofnetwork slice instances or one or more services may be determined based on the analysis. In anembodiment, based on inputs of the analysis that are provided by the AN-COF-SS 208, the NTWSL-ORCH-SS 210 may determine whether any changes are required to the one or more of the pluralityof network slice instances, the one or more services mapped to the one or more of the plurality ofnetwork slice instances, and the allocated resources. The determination of the change required mayinclude determination of whether current and predicted resource occupancy levels of the one or moreof the plurality of network slice instances or the plurality of network slice subnet instances are belowa relevant network slice resource occupancy level threshold, i.e., N-S-RES-OCCUP-THRES. Itshould be noted that, the network slice resource occupancy level threshold may be specified based ona type of the network slice.

[049] In addition, the determination for the requirement for the change may includedetermination of whether there is too much fragmentation of the plurality of network slice instancesor the plurality of network slice subnet instances. For example, the one or more network sliceinstances of same type may be above than network slice instance threshold, i.e., N-S-INST-THRESin same (or overlapping) coverage area, and most of the one or more network slice instances areshareable (i.e., can cater to more than 1 service). Moreover, the determination for the requirement forthe change may include determination of an issue in SLA / KPI adherence levels of the one or more ofthe plurality of network slice instances, or the plurality of network slice subnet instances. Based onabove analysis, if the NTW-SL-ORCH-SS 210 may determine the requirement for the change, thenthe NTW-SL-ORCH-SS 210 may perform actions as illustrated by the step 414.

[050] Further, based on inputs received on analysis of the one or more services by the ANCOF-SS 208, the NTW-SERV-ORCH-SS 204 may determine whether any changes are required tothe one or more services, and the resources allocated to the one or more services. In order to determinethe changes required, the NTW-SERV-ORCH-SS 204 may determine whether current and predictedresource occupancy levels of one or more active service instances are below a relevant serviceresource occupancy level threshold, i.e., SERV-RES-OCCUP-THRES. The service resourceoccupancy level threshold maybe specified based on the service class. In addition, the NTW-SERVORCH-SS 204 may determine if there is an issue in the SLA / KPI adherence levels of the one or moreactive service instances. Further, based on above determination, upon determining the requirementfor the change in the one or more services, the NTW-SERV-ORCH-SS 204 may request the NTWSL-ORCH-SS 210 to carry out the actions described in the step 414 by providing relevant inputsabout the one or more active service instances and the associated resource occupancy levels, etc.

[051] Once the availability of the appropriate resource and the requirement for the change isdetermined, at step 414, slice level utilization of resources may be determined. In other words, theNTW-SL-ORCH-SS 210 may determine resources of each type allocated to each of the plurality ofnetwork slice instances and the plurality of network slice subnet instances across the geographicalareas (also referred as the coverage areas), and the level of occupancy (e.g., the level of occupancymay be determined in percentage). The NTW-SL-ORCH-SS 210 may then prepare a table 500A asdepicted by a FIG. 5A. The table 500A may include resource utilization across different geographicalareas by each of the plurality of network slice instances. In other words, the table 500A may representthe utilization of the plurality of resources across different geographical areas. In an embodiment,splitting of the different geographical area may be done based on tracking area, rectangular grids, orany other method.

[052] In the table 500A, each row of a first column, i.e., network slice instance 502A mayrepresent each of the plurality of network slice instances. Further, each row of a second column, i.e.,resource type 504A may represent a type of resource allocated to each of the plurality of networkslice instances. Each row of a third column, i.e., a resource category 506A represents the category ofeach of the plurality of resources allocated to each of the plurality of network slice instances. Further,last column, i.e., a resource occupancy level 508A may include sub-columns, i.e., an 'Area 1', an'Area 2' and an 'Area 3'. In an embodiment, each sub-columns may correspond to the differentgeographical areas. Moreover, the last column, i.e., the resource occupancy level 508A may representthe level of occupancy of each of the plurality of resources in each of the different geographical areasdepicted via the sub-columns. It should be noted that, the table 500A depicted in the FIG. 5 may befurther extended by showing the resource occupancy levels predicted for the geographical area, forvarious time intervals.

[053] Similar to the table 500A, the NTW-SL-ORCH-SS 210 may then prepare a table 500Bas depicted by a FIG. 5B. The table 500B may include resource utilization across differentgeographical areas by each of the plurality of slice subnet instances. In an embodiment, splitting ofthe different geographical areas may be done based on tracking area, rectangular grids, or any othermethod. In the table 500B, each row of a first column, i.e., network slice subnet instance 502B mayrepresent each of the plurality of network slice instances. Further, each row of a second column, i.e.,network slice instance it belongs to 504B may represent at least one of the plurality of network sliceinstances to which one or more of the plurality of network slice subnet instances may belong to. Eachrow of a third column, i.e., a resource type 506B may represent a type of resource allocated to eachof the plurality of network slice subnet instances. Each row of a fourth column, i.e., a resourcecategory 508B may represents the category of the each of the plurality of resources allocated to eachof the plurality of network slice subnet instances. Further, the last column, i.e., a resource occupancylevel 510B may include sub-columns, i.e., an 'Area 1', an 'Area 2' and an 'Area 3'. In an embodiment,the sub-columns may correspond to the different geographical areas. Moreover, the last column, i.e.,the resource occupancy level 510B may represent the level of occupancy of each of the plurality ofresources in each of the different geographical areas as depicted via the sub-columns.

[054] It should be noted that, the type of each of the plurality of resources and the categoryof each of the plurality of resources may vary depending on type of each of the plurality of subnetinstances. For example, a type of resource in case of Radio Access Network (RAN) may be spectrum,compute, etc. Moreover, a category of resource in case of RAN subnet may be cellular-5 GHz band,cellular mmWaves, cellular-unlicensed, Wi-Fi, cellular-emergency use, cellular-premium spectrum,etc.

[055] Once the utilization of each of the plurality of resources are determined, at step 416, aservice allocation schedule and a service resource utilization may be determined across one or moreservice classes and one or more resource classes for each of the plurality of resources. In anembodiment, the NTW-SL-ORCH-SS 210 may determine service level and service class levelresource utilization over time (including forecasted utilizations) based on one or more of the pluralityof resources allocated to it (including potential scaling up / down as needed) across the differentgeographical areas, and contribution of the one or more of the plurality of resources in overall networkslice instance resource occupancy and network slice subnet instance occupancy level for various typesof the plurality of resources. In order to determine the service level and the service class level resourceutilization along with the contribution of the one or more of the plurality of resources, the NTW-SLORCH-SS 210 may obtain relevant inputs from the AN-COF-SS 208.

[056] The NTW-SL-ORCH-SS 210 may then utilize the relevant inputs obtained from theAN-COF-SS 208 to prepare a table. In other words, the NTW-SL-ORCH-SS 210 may capture thelevel of occupancy of each of the plurality of resources across the one or more services and serviceclasses for the different geographical areas over time. The captured information may be collected andstored in a form of the table as depicted via a table 600 of a FIG. 6. Further, the NTW-SL-ORCH-SS210 may determine the service level and service class level resource utilization over time across thedifferent geographical areas via the table 600. In the table 600, each row of a first column, i.e., serviceclass 602 may depict a class associated with each of the plurality of services. Each row of a secondcolumn, i.e., service ID 604 may represent a unique identification (ID) provided to each of theplurality of services. Each row of a third column, i.e., network slice instance 606 may represent oneof the plurality of network slice instances currently serving one of the plurality of services. Each rowof a fourth column, i.e., 608 may represent one of the plurality of network slice subnet instancecurrently serving one of the plurality of services.

[057] Further, each row of a fifth column, i.e., resource type 610 may represent a type of oneof the plurality of resources being allocated to the one of the plurality of services. Each row of a sixthcolumn, resource category 612 may represent a category of one of the plurality of resources currentlyallocated to the one of the plurality of services. Each row of a last column, i.e., resource occupancylevel 614 may include sub-columns, i.e., an 'Area 1', an 'Area 2' and an 'Area 3'. In an embodiment,the sub-columns may correspond to the different geographical areas. Moreover, the last column, i.e.,the resource occupancy level 614 may represent the level of occupancy of each of the plurality ofresources in each of the different geographical areas as depicted via the sub-columns.

[058] The overall resource occupancy level of a network slice instance by a service or serviceclass may be determined as an average of consolidated resource occupancy levels of its constituentnetwork slice subnet instances (i.e., the plurality of network slice subnet instances). The table 600 ofthe FIG. 6 may be used to determine the overall resource occupancy level, along with the contributionof each service and service class's contribution (in percentage) to the overall resource occupancylevels. In other words, the overall resource occupancy level may depict number of resources beingused by the service and the service class that are being served by the network slice instance (and theconstituent network slice subnet instances). It should be noted that, services belonging to same serviceclass may be served by one or more of the plurality of network slice instances, which, in turn, shallbe composed of one or more of the plurality of network slice subnet instances of same type. In anembodiment, a particular service may be served by resources spanning one or more categories forsame resource type. This may be due to availability constraints, resource cost, requirements for theservice (reliability, SLAs, etc.), resource optimization, etc.

[059] Further, the NTW-SL-ORCH-SS 210 may prepare a detailed allocation map (takingpotential scaling into consideration which will be done to accommodate the traffic, i.e., to be in linewith the traffic pattern or to ensure that the resource occupancy levels don't cross thresholds whichcould impact SLAs / KPIs and / or cause service disruption) including the level of occupancy andutilization of each of the plurality of resource with the service class, the resource type, and theresource category. Moreover, with the relevant inputs obtained from the AN-COF-SS 208, the NTWSL-ORCH-SS 210 may determine resource occupancy trends, any spikes (transient peaks or troughsin occupancy levels), etc. which shall be taken into account, when determining the consolidation plan.

[060] The NTW-SL-ORCH-SS 210 may also determine if there are any improperdistribution of one or more of the plurality of resources to each of the service classes (e.g., a lowerpriority resource or a lower reliability resource allocated to a higher service class, a higher priorityresource allocated to a lower service class, etc.). The determined information may then be stored withan indication for one of the set of possible actions (also referred as possible corrective action orpossible optimization). By way of an example, in case the lower priority resource or the lowerreliability resource is allocated to the higher service class, then in such case at least one of the set ofpossible action may need to be performed. By way of another example, in case a higher priorityresource is allocated to a lower service class, then in such case there may be requirement foroptimization of the higher priority resources, so that the higher priority resources can be freed up tobe able to accommodate another service associated to the higher service class and is more appropriateto use the higher priority resources.

[061] Once the service allocation map and the service resource utilization are determined, atstep, 418, a consolidation plan may be determined. In an embodiment, the NTW-SL-ORCH-SS 210may determine the consolidation plan based on the service allocation map and the service resourceutilization. Moreover, consolidation may include performing of one or more of the set of possibleactions. The set of possible actions may include modification of resource allocation, merging ofnetwork slices, splitting of network slices, modification of network slices, and re-mapping one ormore services to at least one of the network slice instances. It should be noted that, the set of possibleactions may need not to be necessarily carried out in sequence. By way of an example, the NTW-SLORCH-SS 210 may start with the highest service class and carry out the actions relevant to it, andthen continue in descending order of the service classes to perform the set of possible actions relevantto each of those service classes. Alternatively, NTW-SL-ORCH-SS 210 may start with a geographicalarea which has heavy resource constraint and carry out the actions relevant to it, and then continuethe process in descending order of geographical areas with resource constraint level until the NTWSL-ORCH-SS 210 finishes the actions for all the geographical areas. Moreover, when theconsolidation plan needs to be determined because of the new service request, then the NTW-SLORCH-SS 210 may initially decide to determine the set of possible actions for the service class towhich the new service request belongs to, before proceeding further with lower service classes, andthen addressing higher service classes.

[062] In an embodiment, a first possible action from the set of possible actions, i.e.,modification of resource allocation may include two sub-actions, i.e., reallocation of resources to bein line with the service classes and scaling up / down of the plurality of resources (of one or moreresource types and resource categories). By way of an example, in first sub-action, i.e., reallocationof resources to be in line with the service classes, the reallocation of resources may be performed byallocating the one or more of the plurality of resources of an appropriate category to the services ofthe same service class, hence to the network slice instance(s) and the network slice subnet instance(s)catering to those services.

[063] By way of another example, the reallocation of resources may be performed byreallocating the one or more of the plurality of inappropriate resources to other suitable serviceclass(es) or freed up if they are not needed. In addition, the reallocation of resources may be performedin case of SLA / KPI adherence issues for one or more service(s) and / or one or more of the plurality ofnetwork slice instance(s). Moreover, if there are SLA / KPI adherence issues, then resources of highercategory may be allocated to the service or the network slice instance than what it is normally eligiblefor. In such cases, the POL-PROV-SS 202 may be informed to notify the operator for any updates tobilling and / or obtaining a confirmation.

[064] In the second sub-action, i.e., scaling up / down of the plurality of resources, theplurality of resources may have to scaled up / down, based on the reallocation of resources done asdescribed above in the first sub-action. Further, if there are SLA / KPI adherence issues in one or moreservice(s) and / or one or more of the plurality of network slice instance(s), then scaling may berequired. Moreover, even if there is no reallocation, as well as no SLA / KPI adherence issues, thenbased on the analysis of the performance management data on the resource occupancy levels and thetraffic patterns predicted by the AN-COF-SS 208, the plurality of resources may have to be scaledup / down appropriately to be in line with estimated traffic. In addition, if scaling of one or more of theplurality of resources is not feasible due to scarcity of resources of a particular category, even thenthe NTW-SL-ORCH-SS 210 may have to decide to scale up more resources of the higher category.In such cases, the POL-PROV-SS 202 may be informed to notify the operator for any updates tobilling and / or obtaining a confirmation.

[065] Further, a second possible action from the set of possible actions, i.e., merging ofnetwork slices may be performed when there is more than one network slice instance with overlappinggeographical area, and catering to one or more services belonging to the same or similar serviceclasses. In such a case, the NTW-SL-ORCH-SS 210 may decide to merge one or more of the networkslice instances that are catering to one or more services which allow sharing of one or more of theplurality of resources. Moreover, the decision to merge the one or more of the network slice instancesmay also depend on the resource occupancy levels, and level of fragmentation of each of the pluralityof resources across the one or more of the plurality of network slice instances (which will determinethe benefit of consolidation).

[066] It should be noted that merging of the network slices may be simple or complex. Byway of an example, merging of two network slice instances with same geographical area may requireconsolidation of one or more of the plurality of resources, and logical re-mapping of the services tothe merged network slice instance (formed by merging the two network slice instances). Moreover,merging of two network slice instances with similar (overlapping) geographical area may require theconsolidation of one or more of the plurality of resources, logical re-mapping of the services, andmodification of the geographical area of the merged network slice instances to be a superset of thetwo network slice instances being merged. By way of another example, merging of the network slicesmay include merging of a network slice instance, say 'N-S1', with a network slice instance, say 'NS2', in part of a geographical area 'C1'. Once 'N-S1' and 'N-S2' in the geographical area 'C1' aremerged then, the merging of 'N-S1' may be performed with 'N-S3' in another part of the geographicalarea 'C2'. The merging of 'N-S1' and 'N-S2' and 'N-S1' with 'N-S3' as explained above may befeasible only when the service(s) that 'N-S1' is catering to does not span across the geographical area'C1' and the geographical area 'C2'. If the condition is met, then 'N-S1' may be merged with 'N-S2'in the geographical area 'C1', and with 'N-S3' in the geographical area 'C2', and the services cateredby the 'N-S1' will be re-mapped appropriately. Moreover, resource budgets for the two mergednetwork slice instances may also have to re-computed, and the plurality of resources needs to be reallocated accordingly. As will be appreciated, the mechanism described above to perform the mergingof the two-network slice instance may also be applicable for merging of two network slice subnetinstances.

[067] Further, a third possible action form the set of possible actions, i.e., splitting of networkslices may be performed when there may be more than one service mapped to a network slice instance.Moreover, in case of network subnet instance, the splitting of network slice subnet instances may beperformed, when one network slice subnet instance may cater to more than one network slice instance.In an embodiment, the NTW-SL-ORCH-SS 210 may determine split of the network slice instance orthe network subnet instance, when there is disproportionate use of one or more of the plurality ofresources, and it is not feasible to apply sufficient controls to ensure that one consumer (consumermay correspond to the service in case of network slice instance, and network slice instance in caseof the network slice subnet instance) does not affect SLA / KPI of other consumer(s). Moreover,splitting of the network slices may also be required when services belonging to different serviceclasses are mapped to the same network slice instance, leading to different resource categories beingassigned to the same network slice instance, thereby, leading to challenges in consolidation andoptimization.

[068] Further, a fourth possible action form the set of possible actions, i.e., modification ofnetwork slices may be performed when the SLA / KPI issues of a particular network slice subnetinstance is affecting certain services catered to by the network slice instance or affecting the networkslice instance itself. Further, the modification of the network slices may be performed when use ofanother network slice subnet instance may lead to resource optimization, consolidation of the networkslice subnet instances, and when use of another network slice subnet instance may aid in networkslice instance consolidation, etc. In an embodiment, the modification of the network slices mayinvolve changing of the constituents of the network slice instance (or the network slice subnet instancein case of hierarchical network slice subnets).

[069] Further, a fifth possible action form the set of possible actions, i.e., re-mapping one ormore services to at least one of the network slice instances, may be performed when consolidating theplurality of network slice instances, or when the SLA / KPI adherence issues are encountered by theservice and cannot be re-solved using other set of possible actions described above. Further, the remapping may also be done to consolidate services of a certain service class to a smaller set of networkslice instances in order to achieve better resource optimization. Moreover, the re-mapping may alsobe done when a new service request of a lower service class is received and is unable to be fulfilleddue to scarcity of resources. In this case, a service of a higher service class may be re-mapped toanother network slice instance in order to fulfil the new service request. The NTW-SL-ORCH-SS 210may then prepare the consolidation plan based on the determined set of possible actions.

[070] Once the consolidation plan is determined, at step 420, an impact of modifications maybe assessed based on the consolidation plan. In other words, the impact of the set of possible actionsmay be assessed based on the plurality of factors. In an embodiment, the NTW-SL-ORCH-SS 210may assess the impact of modifications determined in the previous step 418. Moreover, for each ofthe set of possible actions, the impact assessment may be done based on policy inputs (provisionedby the operator), dynamic network conditions, active network slice instances, and service instances.The impact assessment may cover, impact (if any) on the SLAs / KPIs of currently active services,impact (if any) on service continuity of currently active services, impact (if any) on the network sliceinstance(s) performance (SLA / KPI adherence level) and / or its constituent network slice subnetinstance(s) performance, impact (if any) on minimum resource availability, and impact onbilling / charging. In an embodiment, the impact on the service continuity of the currently activeservices may particularly be important for services that have strict service continuity requirements,for example, emergency services, premium voice and video services, etc. Further, the impact on thenetwork slice instance(s) performance and / or its constituent network slice subnet instance(s)performance may be considered when a new service request is mapped to it, or during resource orslice modification (including merging and splitting). Moreover, the impact on minimum resourceavailability may be considered so that ability to cater to emergency or high-priority service requestsis not affected. Further, the impact on the billing / charging may be considered when limit-of-creditthreshold reaches faster, thresholds defined by the operator and / or customer, etc. For assessing thisimpact, the NTW-SL-ORCH-SS 210 may interact with the OSS / BSS 102 to obtain relevant inputsthrough the POL-PROV-SS 202. Alternatively, the impact of billing / charging may be defined aspolicies by the operator, so that the NTW-SL-ORCH-SS 210 may simply check policy allowance.

[071] In an embodiment, the impact assessment may be performed by the NTW-SL-ORCHSS 210 with help of inputs received from the AN-COF-SS 208 about the (predicted) resourceoccupancy trends and the resource utilization levels over time, and also taking into consideration,scaling up / down of the plurality of resources (based on rules and thresholds) as needed toaccommodate the (predicted) service's resource occupancy level or the slice's resource occupancylevel, and imposed soft limits and / or imposed hard limits in scaling up of the appropriate resourcesfor the service or the network slice instance, and resorting to alternatives (if any) under thoseconstrained situations. In an embodiment, the alternatives may have an adverse impact on theSLAs / KPIs as well as on service continuity. Further, the soft limits may be imposed by, for e.g., bypolicy, pre-defined rules, delay in bringing up the required hardware resource, etc. Moreover, the hardlimits may be imposed by availability of the hardware resources.

[072] Based on the impact assessment, the NTW-SL-ORCH-SS 210 may also determinenecessary preventive / corrective actions to address or mitigate the (adverse) impact. Thisdetermination may be done using pre-provisioned rules or with the help of the AN-COF-SS 208 or acombination of both. In an embodiment, the preventive / corrective actions may include, changesrequired in the communication network to address the impact(s), and / or timing of updates required tofulfil the new service request or to perform resource optimization, etc., and / or assistance to berequested to other network functions to enable updates to be done smoothly.

[073] By way of an example, after the impact assessment, the NTW-SL-ORCH-SS 210 maythen check on policy inputs and allowances. For example, when the impact assessment is done basedon trigger received for the new service request and policy indicates to carry out one or more of thecorrective / preventive actions with minimum change to network topology and resource allocation,then the NTW-SL-ORCH-SS 210 may decide to implement only one or more of thecorrective / preventive action that is necessary for fulfillment of the new service request. On the otherhand, when network policy indicates service classes higher than 'x' should always be ensured ofSLA / KPI adherence even in resource-constrained situations, then the NTW-SL-ORCH-SS 210 maydecide to carry out one or more of the necessary corrective / preventive actions in order to ensurerequired SLA / KPI adherence.

[074] By way of another example, when policy indicates that a service request of serviceclass 'X' should always be fulfilled even if it means use of resources of the highest category, then theNTW-SL-ORCH-SS 210 may decide to carry out at least one of the corrective / preventive actions thatis relevant for ensuring fulfilment of the service request which is a for a service associated with thatservice class 'X'. Moreover, the corrective / preventive actions determined (based on policy) may alsoinclude the set of possible actions determined, to address any adverse impacts of performing the oneor more of the set of possible actions. For example, when a certain network slice instance is cateringto a critical / emergency service, then the NTW-SL-ORCH-SS 210 may decide not to do any changesto that network slice instance as well as to that critical / emergency service. Moreover, when a certainnetwork slice instance is catering to real-time voice or video services which require latency-sensitiveservice continuity, then the NTW-SL-ORCH-SS 210 may decide to defer any changes to a period oflow traffic, or inform the network functions to not accept new session requests until the changes arecarried out or take other steps to ensure service continuity (for e.g., temporary allocation of alternateresources, temporary borrowing of resources from another N-S instance, etc.).

[075] Once the impact assessment is done, at step 422, necessary modifications may beperformed. In other words, based on the assessed impact, the relevant network function(s) may betriggered to perform at least one of the set of determined possible actions. In an embodiment, theNTW-SL-ORCH-SS 210 may trigger the relevant network functions to carry out the changes (i.e., theat least one of the set of determined possible actions) finalized after the step 420. In reference to FIG.1, the at least one of the set of determined possible actions may be carried out by the NFVO 112,SDN-O 114, RAN Manager 108 (also referred to as domain orchestrators) or by the commonfunctions 120. As mentioned earlier, the at least one of set of determined possible actions may beperformed immediately, deferred until there is no active session, done after a time delay, or doneduring a specific time window. Moreover, performing of the at least one of set of determined possibleactions may be based on instructions received from the NTW-SL-ORCH-SS 210 and / or governed bypolicy. Further, the NTW-SL-ORCH-SS 210 may also trigger the NFVO 112, when any of the at leastone of the set of determined possible actions have to be informed to specific network functions (e.g.,to avoid routing of traffic to the network functions undergoing a change) by the NFVO112. In anembodiment, such information may be passed to the network function(s) themselves withoutinvolvement of the NFVO112.

[076] Once the trigger to perform the at least one of the set of determined possible solutionis generated and the associated actions are carried out successfully, at step 424, an effectiveness ofperforming the at least one of the set of possible actions may be verified. In addition, based on theverified effectiveness, one or more corrective actions may be performed. In an embodiment, whenabove steps, i.e., the step 414 to the step 422 are carried upon receiving the new service request, thenafter performing the at least one of the set of possible actions, the NTW-SL-ORCH-SS 210 mayrequest the NTW-ST-CONF-SS 214 to provide a suitable network shell hierarchy for the new servicerequest. Moreover, the NTW-ST-CONF-SS 214 may also consider resources of higher categories forfulfilling the new service request if needed, based on guidance from policy. Further, the NTW-SLORCH-SS 210 may also inform the SL-SRV-MON-SS 212 about the at least one of the set of possibleactions performed. The SL-SRV-MON-SS 212 may monitor the SLA / KPI adherence levels as wellas any faults. The SL-SRV-MON-SS 212 may receive help of the AN-COF-SS 208 to determinecorrelation of any drop or rise in the SLA / KPI adherence level due to the at least one of the set ofpossible actions carried out by the NTW-SL-ORCH-SS 210 and informs the NTW-SL-ORCH-SS 210accordingly.

[077] Based on feedback from the SL-SRV-MON-SS 212, the AN-COF-SS 208, and theNTW-ST-CONF-SS 214 (service request could be fulfilled or not) on the effectiveness of performingthe at least one of the set of possible actions, the NTW-SL-ORCH-SS 210 may perform necessarycorrective action(s) in case the SLA / KPI adherence level is dropped or did not improve significantly.In this case, the corrective action(s) may correspond to determination of at least one of the set ofpossible actions as described in the step 418 taking into consideration one or more of the set ofpossible actions performed earlier. In addition, the NTW-SL-ORCH-SS 210 may perform necessarycorrective action in case the new service request received could not be fulfilled. In this case, thecorrective action(s) may correspond to determination of at least one of the set of possible actions asdescribed in the step 418 taking into consideration one or more of the set of possible actions performedearlier, and being more aggressive in optimization of resources of lower service classes. Moreover,the NTW-SL-ORCH-SS 210 may periodically assess the effectiveness of the at least one of the set ofpossible actions, and accordingly refine the pre-threshold for determining when changes should bedone, level of optimization to be done, etc. This self-adaptation results in improved operation over aperiod of time.

[078] It will be appreciated that, for clarity purposes, the above description has describedembodiments of the invention with reference to different functional units and processors. However,it will be apparent that any suitable distribution of functionality between different functional units,processors or domains may be used without detracting from the invention. For example, functionalityillustrated to be performed by separate processors or controllers may be performed by the sameprocessor or controller. Hence, references to specific functional units are only to be seen as referencesto suitable means for providing the described functionality, rather than indicative of a strict logical orphysical structure or organization.

[079] Various embodiments of the invention provide method and system for effective servicefulfilment in a communication network. The method and system may first determine utilization ofeach of a plurality of resources for each of a plurality of network slice instances. In an embodiment,each of the plurality of network slice instances may include a set of network slice subnet instances.The method and system may then determine a service allocation schedule and a service resourceutilization across one or more service classes and one or more resource classes for each of the pluralityof resources. Further, the method and system may determine at least one of a set of possible actionsrequired to be performed in at least one of the plurality of resources, a plurality of services, and theplurality of network slice instances based on a consolidation plan. In an embodiment, theconsolidation plan may be created based on the service allocation schedule and the service resourceutilization. Additionally, the method and system may assess an impact of each of the set of possibleactions based on a plurality of factors. In an embodiment, the plurality of factors may include at leastone of dynamic network conditions, active network slice instances, and service instances. Thereafter,the method and system may trigger a relevant network function(s) to perform at least one of the setof determined possible actions based on the assessed impact.

[080] The specification has described method and system for effective service fulfilment ina communication network. The illustrated steps are set out to explain the exemplary embodimentsshown, and it should be anticipated that ongoing technological development will change the mannerin which particular functions are performed. These examples are presented herein for purposes ofillustration, and not limitation. Further, the boundaries of the functional building blocks have beenarbitrarily defined herein for the convenience of the description. Alternative boundaries can bedefined so long as the specified functions and relationships thereof are appropriately performed.Alternatives (including equivalents, extensions, variations, deviations, etc., of those described herein)will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein. Suchalternatives fall within the scope and spirit of the disclosed embodiments.

[081] Furthermore, one or more computer-readable storage media may be utilized inimplementing embodiments consistent with the present disclosure. A computer-readable storagemedium refers to any type of physical memory on which information or data readable by a processormay be stored. Thus, a computer-readable storage medium may store instructions for execution byone or more processors, including instructions for causing the processor(s) to perform steps or stagesconsistent with the embodiments described herein. The term "computer-readable medium" should beunderstood to include tangible items and exclude carrier waves and transient signals, i.e., be nontransitory. Examples include random access memory (RAM), read-only memory (ROM), volatilememory, nonvolatile memory, hard drives, CD ROMs, DVDs, flash drives, disks, and any otherknown physical storage media.

[082] It is intended that the disclosure and examples be considered as exemplary only, witha true scope and spirit of disclosed embodiments being indicated by the following claims.

Claims

1. A method (300) for effective service fulfilment in a communication network, the method (300) comprising: determining (302), by a network device, utilization of each of a plurality of resources for each of a plurality of network slice instances, wherein each of the plurality of network slice instances includes a set of network slice subnet instances; determining (304), by the network device, a service allocation schedule and a service resource utilization across one or more service classes and one or more resource classes for each of the plurality of resources; determining (306), by the network device, at least one of a set of possible actions required to be performed in at least one of the plurality of resources, a plurality of services, and the plurality of network slice instances based on a consolidation plan, wherein the consolidation plan is created based on the service allocation schedule and the service resource utilization; assessing (308), by the network device, an impact of each of the set of possible actions based on a plurality of factors, wherein the plurality of factors comprises at least one of dynamic network conditions, active network slice instances, and service instances; and triggering (310), by the network device, a relevant network function(s) to perform at least one of the set of determined possible actions based on the assessed impact.

2. The method (300) of claim 1, further comprising: determining, by the network device, an availability of an appropriate resource from the plurality of resources upon receiving a new service request, wherein the new service request includes performance requirements, a priority, a class associated with users, a geographical area of a service, a service class, and a duration of the service; and identifying, by the network device, a requirement for a change in one or more of the plurality of network slice instances to fulfil the new service request.

3. The method (300) of claim 2, wherein determining the availability comprises determining, by the network device, a requirement of the appropriate resource for the new service request based on a set of service factors, wherein the set of service factors include service characteristics, service performance requirement, and service dimensions, and wherein determining availability of the appropriate resource comprises: fetching, by the network device, a first set of resource budgets and service performance requirement for each of the set of network slice subnet instances of the plurality of network slice instances; and determining, by the network device, a network shell hierarchy using a template hierarchy, wherein the network shell hierarchy includes a slice subnet hierarchy, wherein determining the network shell hierarchy comprises: identification of one of a reuse of an existing network slice instance or creation of a new network slice instance, and wherein creation of the new network slice instance comprises determination of one of a reuse of an existing network slice subnet instance or creation of a new network slice subnet instance based on the slice subnet hierarchy.

4. The method (300) of claim 1, further comprising: identifying, by the network device, a requirement for a change in one or more of the plurality of network slice instances or one or more services based on an analysis of at least one of fault management data or performance management data, wherein identifying the requirement for the change in one or more of the plurality of network slice instances or one or more services further comprises: receiving, by the network device, the at least one of the fault management data or the performance management data from the communication network; analyzing, by the network device, the at least one of the fault management data or the performance management data to identify a plurality of faults or a plurality of performance issues in the communication network, based on a pre-defined threshold, predefined performance criteria, or service level criteria; and analyzing, by the network device, an impact of the plurality of faults or the plurality of performance issues on at least one of the plurality of network slice instances, the set of network slice subnet instances, services and service classes, and impacted geographical areas.

5. The method (300) of claim 1, wherein: determining the service allocation schedule and the service resource utilization comprises determining service level resource utilization and service class level resource utilization based on the plurality of resources allocated to one or more service classes and resource classes in various geographical areas associated with the service; the set of possible action comprises modification of resource allocation, merging of network slices, splitting of network slices, modification of network slices, and re-mapping one or more services to at least one of the network slice instances; and the impact assessment of each of the set of possible actions includes at least one of an impact on service level criteria or key performance indicators of currently active services, an impact on service continuity of currently active services, an impact on performance of a network slice instance(s) or a network slice subnet instance upon mapping the new service or during at least one of the set of possible actions, an impact of minimum resource availability, and an impact on billing.

6. The method (300) of claim 1, further comprising: verifying, by the network device, an effectiveness of performing the at least one of the set of modifications based on a new network slice shell hierarchy provided for the new service request; and performing, by the network device, a corrective action based on the effectiveness of the at least one of the set of modifications.

7. A system (100) for effective service fulfilment in a communication network, the system comprising: a processor; and a memory communicatively coupled to the processor, wherein the memory stores processor executable instructions, which, on execution, causes the processor to: determine (302) utilization of each of a plurality of resources for each of a plurality of network slice instances, wherein each of the plurality of network slice instances includes a set of network slice subnet instances; determine (304) a service allocation schedule and a service resource utilization across one or more service classes and one or more resource classes for each of the plurality of resources; determine (306) at least one of a set of possible actions required to be performed in at least one of the plurality of resources, a plurality of services, and the plurality of network slice instances based on a consolidation plan, wherein the consolidation plan is created based on the service allocation schedule and the service resource utilization; assess (308) an impact of each of the set of possible actions based on a plurality of factors, wherein the plurality of factors comprises at least one of dynamic network conditions, active network slice instances, and service instances; and trigger (310) a relevant network function(s) to perform at least one of the set of determined possible actions based on the assessed impact.

8. The system (100) of claim 7, wherein the processor executable instructions further cause the processor to: determine an availability of an appropriate resource from the plurality of resources upon receiving a new service request, wherein the new service request includes performance requirements, a priority, a class associated with users, a geographical area of a service, a service class, and a duration of the service; and identify a requirement for a change in one or more of the plurality of network slice instances to fulfil the new service request.

9. The system (100) of claim 8, wherein, to determine the availability, the processor executable instructions further cause the processor to: determine a requirement of the appropriate resource for the new service request based on a set of service factors, wherein the set of service factors include service characteristics, service performance requirement, and service dimensions, and wherein, to determine availability of the appropriate resource, the processor executable instructions further cause the processor to: fetch a first set of resource budgets and service performance requirement for each of the set of network slice subnet instances of the plurality of network slice instances; and determine a network shell hierarchy using a template hierarchy, wherein the network shell hierarchy includes a slice subnet hierarchy, and wherein, to determine the network shell hierarchy, the processor executable instructions further cause the processor to: identify one of a reuse of an existing network slice instance or creation of a new network slice instance, and wherein creation of the new network slice instance comprises determination of one of a reuse of an existing network slice subnet instance or creation of a new network slice subnet instance based on the slice subnet hierarchy.

10. The system (100) of claim 7, wherein the processor executable instructions further cause the processor to: identify a requirement for a change in one or more of the plurality of network slice instances or one or more services based on an analysis of at least one of fault management data or performance management data, wherein, to identify the requirement for the change in one or more of the plurality of network slice instances or one or more services, the processor executable instructions further causes the processor to: receive the at least one of the fault management data or the performance management data from the communication network; analyze the at least one of the fault management data or the performance management data to identify a plurality of faults or a plurality of performance issues in the communication network, based on a pre-defined threshold, pre-defined performance criteria, or service level criteria; and analyze an impact of the plurality of faults or the plurality of performance issues on at least one of the plurality of network slice instances, the set of network slice subnet instances, services and service classes, and impacted geographical areas.

11. The system (100) of claim 7, wherein: to determine the service allocation schedule and the service resource utilization, the processor executable instructions further cause the processor to: determine service level resource utilization and service class level resource utilization based on the plurality of resources allocated to one or more service classes and resource classes in various geographical areas associated with the service, the set of possible action comprises modification of resource allocation, merging of network slices, splitting of network slices, modification of network slices, and re-mapping one or more services to at least one of the network slice instances; and the impact assessment of each of the set of possible actions includes at least one of an impact on service level criteria or key performance indicators of currently active services, an impact on service continuity of currently active services, an impact on performance of a network slice instance(s) or a network slice subnet instance upon mapping the new service or during at least one of the set of possible actions, an impact of minimum resource availability, and an impact on billing.

12. The system (100) of claim 7, wherein the processor executable instructions further cause the processor to: verify an effectiveness of performing the at least one of the set of modifications based on a new network slice shell hierarchy provided for the new service request; and perform a corrective action based on the effectiveness of the at least one of the set of modifications.