There are a number of protocols that may be employed in order to provide the Voice over IP VoIP communication services. In VoIP system, H.323 and Session Initiation Protocol SIP are the two major standards. Both of these signaling protocols provide mechanisms for multimedia teleconferencing services. Although the two protocols architecture is quite similar, they have many differences. This system presents Voice Video over IP communication and summarizes the differences and performance of two major VoIP protocols, H.323 and SIP according to the packet delay variation, jitter, packet loss, and Packet end to end delay. It is found that both of them are non interoperable, approaching each other, their focus and applicability is still different. In this paper, the system is designed and configured by Graphical Network Simulator GNS3 and analyzed performance by Opnet Modeler Simulation. Thet Zaw Aye "Performance Analysis between H.323 and SIP over VoIP" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26647.pdf