A Structured Approach to OSPF Implementation and Testing in Hybrid Virtual Networks

Modern enterprise networks increasingly rely on virtualized infrastructure to achieve scalability, flexibility, and cost efficiency. However, integrating heterogeneous Layer 3 routing mechanisms—such as hardware-based Layer 3 switching and software-based router-on-a-stick architectures—introduces significant challenges in maintaining seamless connectivity, scalability, and fault tolerance. This paper presents a structured implementation and evaluation of the Open Shortest Path First (OSPF) dynamic routing protocol within a VMware-based hybrid virtual network environment. The proposed architecture unifies multiple VLAN segments operating across Switched Virtual Interfaces (SVI) and Router-on-a-Stick (RoaS) configurations under a single OSPF Area 0 backbone. OSPF dynamically exchanges topology information, enabling automatic route computation and convergence across disparate routing domains. Experimental validation demonstrates successful neighbor adjacency formation, accurate routing table population with an administrative distance of 110, and reliable end-to-end connectivity between internal VLANs and external networks through Network Address Translation (NAT). The results confirm that OSPF provides a scalable, resilient, and efficient routing solution for complex virtualized enterprise networks.