Global market revenue of VoIP and IMS equipment revenue 2017-2023, by product
Service providers' revenue from voice over Internet Protocol (VoIP) and IP multimedia subsystem (IMS) equipment amounted to around four billion U.S. dollars in 2018, down from 4.3 billion in 2017. In 2018, Call Session Control Function (CSCF) servers for IMS networks generated 1.25 billion U.S. dollars in product revenue. Slowing voice over long-term evolution (VoLTE) network deployments and lowered prices resulted from competitive factors are reasons behind the market decline.