IP telephony, also known as voice over internet protocol (VoIP), allows users to make phone calls using an internet connection rather than a traditional phone line. It works by converting analog audio signals into digital data that can be transmitted over the internet. There are several types of IP telephony including PC-to-PC, PC-to-phone, phone-to-phone, and phone-to-PC. The H.323 protocol is one of the main standards used to establish IP telephony calls and supports terminals, gateways, and multipoint control units to enable real-time audio and video transmission over IP networks. IP telephony offers cost savings compared to traditional telephone networks but also faces challenges around emergency calls and