Comparative Study of RIP, OSPF, and EIGRP in VoIP Networks Across Different Ethernet Topologies

Voice over Internet Protocol (VoIP) has revolutionized communication by offering a flexible and cost-effective alternative to traditional telephony using internet-based voice transmission. This paper investigates the performance of VoIP traffic on various network topologies (mesh, tree, and star) using OPNET Modular 14.5 for simulation. It analyzes the impact of different routing protocols and Quality of Service (QoS) mechanisms on important performance metrics including jitter, packet delay, and throughput. Research underscores the benefits and constraints of each topology and routing protocol for maintaining high-quality voice communication. Despite their simplicity, star topologies are vulnerable to single points of failure. Tree topologies strike a compromise between possible network weaknesses and scalability. This paper presents a detailed comparison of various network topologies, demonstrating that the Enhanced Interior Gateway Routing Protocol (EIGRP) is the most suitable for achieving high scalability. Additionally, it analyzes the significance of QoS in improving VoIP performance, emphasizing its impact on call quality and network reliability, and concluding that for applications like video or voice conferencing, star topology is the best suited while for large scale applications like database systems and Wide Area Network (WAN) tree topology is the best suited.