IP Multimedia Subsystem has been around for a long time, and now that it is gaining traction with VoLTE it is becoming a viable solution for medium to large enterprise communications with revenue expected to reach $1.2 billion (€866 million) through 2019, according to ABI Research. The analyst company said there were various reasons that prevented IMS from becoming an alternative to Unified Communication in the enterprise before 2013: it was too bulky, costly, and complex. However, as IMS moves towards virtualisation, the cloud, and data centres, it is feasible to deploy it the enterprise. Alcatel-Lucent is leading the way with its IMS enterprise communication solution, although it is taking a cautious step into the market. Ericsson is also offering an IMS solution for the enterprise. Other vendors with IMS-like solutions include, but are not limited to, Avaya and BroadSoft. Report