VoIP (Voice over IP)

Technology for delivering voice communication and multimedia sessions over IP networks instead of traditional circuit-switched telephone networks. VoIP converts analog voice signals into digital packets transmitted via protocols such as SIP (signaling), RTP (media), and SRTP (secure media). It enables features like video conferencing, instant messaging integration, and PSTN connectivity via SIP trunks. Key challenges include jitter, packet loss, and NAT traversal, which require QoS and STUN/TURN for media.