 VIRTUALIZED EPC: CHALLENGES/OPPORTUNITIES Network function scaling should be independent, e.g., data VS. control plane functions. Deployment of EPC, e.g., single data center over multiple DCs... Efficient resiliency schemes by utilizing VNF instance migration. Alternative migration/co-existence paths: single VS. coexistence of separate mobile cores Orchestration and automation Service decomposition Provisioning and configuration automation Auto-scaling High-availability Service insertion for stateful services On-demand service chaining Integration with or orchestration/provisioning systems No standard deployment process or API Licensing challenges Vendors like to license boxes (instances), not throughput CONCLUSION The introduction of SDN, orchestration techniques and virtualization advances have materialized the comparatively older idea of Network Function Virtualization which when first brought up was not really capable of being realized. NFV that brings structural change in the telecommunication infrastructure that will definitely result into cost efficiencies, market expansions and improvement to telecommunication industry infrastructure and applications. The disaggregation of the traditional roles and technology in telecommunications applications results into NFV. However, virtualization alone is not the perfect solution to all service deployment problems; but, actually presents new reliability problem vectors that a service orchestration system or architecture has to mitigate. The researchers has already working in decomposing existing services into their functional elements with varying opinions on the granularity of this decomposition. Downloaded 4/15/2022 9:44:49 AM Nova Southeastern University IP Address: 137.52.76.29 Virtualizing Network Functions in Software-Defined Networks The decomposition will certainly influence service chaining resiliency and availability of overall services and individual elements. Simply, NFV is a killer use-case for open stack. At last, it is explicit that traditional vendor