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<h1 id="lifecycle-management-lcm">Lifecycle Management - LCM</h1>
<p><strong>Intended Audience: OpenSlice Service Designers</strong></p>
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<p>Lifecycle Management: The orchestration framework handles the activation, termination and any necessary modifications throughout the service lifecycle.</p>
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<p>In OpenSlice the Lifecycle of a service follows in general the concept of Network Slice lifecycle as defined by 3GPP.</p>
<p><a class="glightbox" href="../lcm/img01.png" data-type="image" data-width="100%" data-height="auto" data-desc-position="bottom"><img alt="lcm" src="../lcm/img01.png" /></a></p>
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<h2 id="introduction-in-openslice-lcm">Introduction in OpenSlice LCM</h2>
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<p>OpenSlice adopted the LCM model by 3GPP and mapped to the TMF model service state. Next we discuss briefly the process and the relationships.</p>
<p>The lifecycle of a service, particularly in the context of Network Service lifecycle encompasses several stages that ensure the service is effectively planned, deployed, managed, and eventually decommissioned. </p>
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<p>Here is an overview of these stages and relationships with OpenSlice:</p>
<h3 id="0-preparation-phase">0. Preparation Phase</h3>
<p>This phase is performed by Service Designers</p>
<h4 id="service-design">Service Design:</h4>
<ul>
<li><strong>Requirements Gathering:</strong> Collect service requirements from stakeholders, including performance metrics, quality of service (QoS), security needs, and geographical coverage.</li>
<li><strong>Service Specification:</strong> Define the service in terms of functionalities, attributes, and dependencies. This can be formalized using standardized templates such as the GSMA Generic Slice Template (GST).</li>
<li><strong>Resource Planning:</strong> Identify and plan the required resources, including network functions, computing power, storage, and connectivity, inclluding network function configurations.</li>
<li><strong>Expose to Service Catalog</strong>: Expose to service catalog for user ordering.</li>
</ul>
<p><strong>Next phases are handled by the Service Orchestrator after a service is scheduled for instantiation</strong></p>
<p><strong>If it is a bundle of services, each services follows its own Lifecycle!</strong></p>
<h3 id="1-instantiation-phase">1. Instantiation Phase</h3>
<h4 id="service-instantiation">Service Instantiation:</h4>
<ul>
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<li><strong>Configuration:</strong> Configure the network service according to the specifications including the user requirements from the service order, ensuring that all components are correctly set up to provide the desired service.</li>
<li><strong>Resource Allocation - Feasibility check:</strong> Allocate the necessary physical and virtual resources based on the service specification. This includes any containerized resources, virtual network functions (VNFs) and software-defined networking (SDN) components. (This step is not performed in OpenSlice)</li>
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<li>OpenSlice Service Orchestrator creates the services at "RESERVED" state</li>
<li><strong>User Notification:</strong> There could be an email notification from the system (if Bugzilla is configured)</li>
</ul>
<h4 id="service-deployment">Service Deployment:</h4>
<ul>
<li><strong>Activation:</strong> OpenSlice Service Orchestrator activates the network service and makes the service available to the end-users. This may involve:</li>
<li>Create any related services that the service depends on</li>
<li>Contacting all related controllers during provisioning, e.g. Kubernetes controllers, Kubernetes operators, MANO Orchestrators, RAN controllers, SDN Controlles, or other external services (e.g. via REST calls)</li>
<li>Scheduling instantiation, Resolving dependencies and passing paramemters between controllers,</li>
<li>setting up user accounts, provisioning access credentials -this is performed either offline or via other services.</li>
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<li>OpenSlice Service Orchestrator if everything is succesful puts the service at "ACTIVE" state</li>
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<li><strong>User Notification:</strong> There could be an email notification from the system (if Bugzilla is configured)</li>
</ul>
<h3 id="2-operation-phase">2. Operation Phase</h3>
<h4 id="service-operation">Service Operation:</h4>
<ul>
<li><strong>Lifecycle Management:</strong> Manage the network slice throughout its lifecycle, including scaling, reconfiguration, and adaptation to changing requirements. </li>
<li>In OpenSlice this is performed with Lifecycle management Rules (see next)</li>
</ul>
<p>In this phase the Service Designer can define several aspects. <strong>Be aware that these are NOT performed automatically by OpenSlice - further examples and future enhancements will address these</strong>. This could include:</p>
<ul>
<li><strong>Monitoring:</strong> Continuously monitor the service for performance, availability, and compliance with SLAs. Utilize tools for real-time tracking and alerts for any anomalies or performance degradation.</li>
<li><strong>Maintenance:</strong> Conduct regular maintenance activities, including software updates, patching, and optimization to ensure the service runs smoothly.</li>
<li><strong>Scaling:</strong> Dynamically scale the resources up or down based on the demand and performance requirements.</li>
<li><strong>Fault Management:</strong> Detect and resolve faults in the network slice to minimize downtime and maintain service quality.</li>
</ul>
<h3 id="3-decommissioning-phase">3. Decommissioning Phase</h3>
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<ul>
<li><strong>Service Termination:</strong> Service Orchestrator terminates the network service. This may involve:</li>
<li>Terminate any related services that the service depends on</li>
<li>Contacting all related controllers during termination to release resources, e.g. Kubernetes controllers, Kubernetes operators, MANO Orchestrators, RAN controllers, SDN Controlles, or other external services (e.g. via REST calls)</li>
<li>Scheduling termination, Resolving dependencies and passing paramemters between controllers</li>
<li>OpenSlice Service Orchestrator, if everything is succesful, puts the service at "TERMINATED" state</li>
<li><strong>User Notification:</strong> There could be an email notification from the system (if Bugzilla is configured)</li>
</ul>
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<h3 id="high-level-example-enhanced-mobile-broadband-embb-service-lifecycle">High level example: Enhanced Mobile Broadband (eMBB) Service Lifecycle</h3>
<ol>
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<li>
<p><strong>Preparation:</strong></p>
</li>
<li>
<p>Define eMBB service requirements for high bandwidth and low latency.</p>
</li>
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<li>Create an eMBB service specification template specifying related services and resources to Kubernetes Operators, VNFs for content delivery and traffic management.</li>
<li>
<p>Expose to catalog</p>
</li>
<li>
<p><strong>Instantiation:</strong></p>
</li>
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<li>
<p>Instantiate other services and allocate resources such as edge computing nodes and high-capacity links.</p>
</li>
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<li>
<p>Configure the service to prioritize video streaming traffic.</p>
</li>
<li>
<p><strong>Operation:</strong></p>
</li>
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<li>
<p>Monitor the service to ensure it meets high-bandwidth requirements.</p>
</li>
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<li>
<p>Scale up resources during peak usage periods, such as live sports events.</p>
</li>
<li>
<p><strong>Decommissioning:</strong></p>
</li>
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<li>
<p>Notify users about service termination.</p>
</li>
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<li>Decommission the network service, reclaiming resources for other services.</li>
</ol>
<h2 id="probe-further">Probe further</h2>
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<ul>
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<li>See 3GPP <a href="https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=3091">Lifecycle</a></li>
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</ul>
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