Monday 20 July, 2026
With the rapid development of communication technologies, especially the widespread application of VoIMS (Voice over IP Multimedia Subsystem) technologies, traditional audio in Customized Alerting Tone (CAT) no longer meets the growing demand for multimedia experiences. Video Customized Alerting Tone (vCAT), as an upgrade of CAT to video format, has emerged and quickly gained momentum in some countries. It is a derivative application based on VoIMS communication technologies, which transformed the ordinary network CAT during the alerting phase into video media playback, significantly enriching the user experience during the waiting period before a call is connected.
This document specifies a unified set of terminal requirements for vCAT service, aiming to enhance consistency, interoperability, and user experience of vCAT service, which should help global adoption of vCAT.
